Download To view the CORA 2016 Annual Meeting Abstract Listing, please

Canadian Orthopaedic Residents’ Association
Annual Meeting
Abstract Listing
Thursday, June 16, 2016
Hilton Québec Hotel, Beauport Room
CORA acknowledges the following sponsors for their generous support:
Gold Sponsors ($2000 or more)
Silver Sponsors ($1000 to $1999)
1
CORA PODIUM ABSTRACTS • JUNE 16, 2016
CORA 01
Incidence, Etiology and Prevention of Football Injuries: Prospective Cohort Study in High
School Athletes
Mireille Marquis, Université Laval
Stéphane Pelet
Purpose: Nowadays, about 1.5 million high school students are playing football in the USA.
Football is a contact sport requiring high intensity training and this is why injuries are so frequent.
Epidemiology and risk factors of sport traumatisms have been studied in many sports, but literature
about football injuries is poor, and even more so in a paediatric population.
The goal is to create an injury database in order to determine incidence, characteristics and risk
factors of high school football traumatisms. The final objective is to propose efficient and adapted
prevention strategies to reduce number and severity of injuries.
Method: This is a prospective cohort study including football players of a Canadian high school. In
the beginning of the season, students filled in forms about their personal characteristics and
biometric values. As we went through the season, injuries have been reported by physiotherapists
and players. Injury incidence and frequency by 1000 sport exposures have been calculated. The
correlation between risk factors related to players and traumatisms have been calculated with a
multivariate analysis (One-factor ANOVA) with an alpha error arbitrarily set at 5%. Comparative
analyses among subgroups have been realized with Chi-square, Student and Fisher tests.
Results: One hundred sixty-one athletes (among a total of 165 players, participation = 97.6%) took
part in the study. One hundred thirty-seven injuries among 89 athletes (53,4%) have been
reported. This equals 21,6 injuries / 1000 sport exposures. The most part occurred during games
(66,17% = 61,8/1000exp vs 33,83% = 9,83/1000exp, p˂0,01). We reported 34 traumatic brain
injuries, 52 tendonitises or strains, and 51 other traumatic lesions (sprains, contusions and
fractures). A link was noted between injuries and alcohol consumption (p=0,05), past injuries
(p˂0,01), higher experience (p˂0,01), defensive line (p=0,05) and important or severe stress
(p=0,06).
Conclusion: Football injuries in high school athletes are an important problem and need special
attention. This prospective study shows a higher injury frequency by 1000 sports exposures than
what is known in other contact sports (soccer, hockey). Prevention strategies are required and
should include modifications in training techniques and teaching of good health habits. These
strategies need to be validated in future studies.
2
CORA 02
Painful Knees after Total Knee Arthroplasty: New Insights from Kinematics
Gabriel Larose, University of Manitoba
Célia Planckaert, Pierre Ranger, Marc Lacelle, Alexandre Fuentes, Danièle Bédard, Julio
Fernandes, Hai Nguyen, Guy Grimard, Nicola Hagemeister
Purpose: Total knee arthroplasty (TKA) is recognized as an effective treatment for end-stage knee
osteoarthritis. Up to 20% of these patients are unfortunately unsatisfied due to anterior knee pain
from unknown origin. The aim of this study is to compare knee 3D kinematics during gait of
patients with anterior knee pain after TKA to an asymptomatic TKA group. Our hypothesis is that
the painful TKA group would exhibit known kinematics characteristics during gait that increase
patellofemoral (PF) stresses (i.e. dynamic flexion contracture, valgus alignment, valgus collapse or
a quick internal tibial rotation movement) compared to the TKA asymptomatic group.
Method: Thirty-eight patients (45 knees) were recruited 12-24 months post-surgery done by one of
three experienced orthopaedic surgeons (31 unilateral TKA and seven bilateral TKA, all using the
same knee implant). Patients were divided according to their KOOS pain score (with a cut-off at
6/20 to be included in the painful group). The KOOS questionnaire was also used to assess
activities of daily living, symptoms, sports and quality of life. A complete clinical and radiological
work up was done on the painful group to exclude those with known explanation for pain (i.e.
loosening, malrotation, infection and clinical instability). 3D knee kinematics during treadmill
walking was captured and computed using the Knee KGTM system.
Results: Only the BMI was statistically different between the groups, there is no difference for the
age, gender, walking speed. Painful TKA presented two of the known kinematic characteristics
identified for patients suffering from PF syndrome. Indeed, a dynamic flexion contracture with a
lower flexion during loading and stance and a loss of excursion in flexion during loading was
observed. Moreover, painful TKA exhibited a valgus alignment during stance, whereas the painfree group remained at 4° varus (p<0.01).
Conclusion: Since a higher valgus alignment increases the Q angle, which lateralizes the patella
and increases PF stresses, results provide new insight on origin of symptoms. Conservative
treatments for PF pain syndrome have shown to address the valgus alignment and improve
symptoms; therefore the next step will be to assess the impact on pain level and alignment during
gait of a personalized conservative management for the painful TKA group. Additionally, a study
assessing the change in the radiological and dynamic alignment from pre to post surgery could
bring valuable insight on the impact of surgical procedure on anterior knee pain.
3
CORA 03
The Effect of Neck Shaft Angle on Joint Loads and Contact Mechanics in Reverse Shoulder
Arthroplasty
Irfan N. Abdulla, Western University
G. Daniel Langohr, Josh W. Giles, James A. Johnson, George S. Athwal
Purpose: Reverse shoulder arthroplasty (RSA) is a common and effective treatment option for rotator
cuff tear arthropathy, complex proximal humerus fractures, and as a salvage procedure for failed
primary shoulder arthroplasty. Computational models have suggested that reducing neck shaft (N-S)
angle can increase impingement-free abduction range of motion (ROM). However, very little is known
of the associated effects of altering this variable on implant contact mechanics and subsequent implant
wear. Using a cadaveric model, the purpose of this in-vitro biomechanical study was to investigate the
effects of N-S angle on RSA joint loads and range of motion and to then use this data of evaluate the
effects of N-S angle on RSA contact mechanics using a finite element model. We hypothesized that
reducing N-S angle would increase adduction ROM, but the associated changes in implant geometry
would have a negative effect on articular contact mechanics.
Method: A custom instrumented RSA implant construct capable of measuring joint forces and varying
N-S angle (155 , 145 , 135 )was implanted in 7 fresh-frozen cadaveric shoulders (age: 71 ± 9 yrs). A
shoulder simulator capable of independently loading musculature to produce active glenohumeral and
scapulothoracic motion was used to simulate active and passive motion. Joint load measurements from
each specimen were then employed in a finite element model (ABAQUS v6.12) to investigate the effect
of changing N-S angle on RSA contact area and maximum contact stresses.
Results: When N-S angle was reduced (155→ 145 → 135) no significant effects were detected for
joint load (P=0.941) or joint load angle (P=0.906). Decreasing N-S angle significantly decreased the
cup edge angle (P=0.003). When N-S angle was decreased, we found no significant effects on internal
of external rotation (P>0.21), we found that decreasing N-S angle had a significant affect on adduction
range of motion with both the 145 and 135 N-S angles providing greater range of motion than the
155 (P=0.017 and P=0.013 respectively). Although not statistically significant, we found abduction
range of motion was decreased as N-S angle decreased (P>0.093). In terms of contact mechanics, a
reduction in N-S angles from 155 to 145 caused no changes in peak contact stresses (P=0.248).
However, a change in N-S angle from 155-135 significantly increased stress (P=0.006). This was
most evident at high abduction angles with the 135 NS angles producing nearly double the contact
stress.
Conclusion: Our findings agree with current literature that suggests that reducing N-S angle will have
a positive effect on adduction range of motion. However, the result of our finite element analysis
demonstrates that this increase in adduction range of motion will negatively impact contact mechanics
across the implant bearing surface. With reduced N-S angle, we found increased maximum contact
stresses, most notably at the inferior edge of the implant. The location of the maximum contact stress is
significant as retrieval studies have shown that the predominant area of wear in RSA is at this inferior
edge. As such, polyethylene wear in this area could potentially be amplified when N-S angles are
altered to achieve greater range of motion. An important balance between optimizing range of motion
and contact mechanic considerations will need to be made when considering decreasing N-S angle in
RSA.
4
CORA 04
PHOSPHO1 is Essential for Normal Bone Fracture Healing
Mina W. Morcos, McGill University
Hadil Al-Jallad, Jose Luis Millan, Reggie Hamdy, Monzur Murshe
Purpose: Bone fracture healing is regulated by a series of complex physicochemical and
biochemical processes. One of these processes is bone mineralization, which is vital for normal
bone development, its biomechanical competence and fracture healing. Phosphatase, orphan 1
(PHOSPHO1), a bone-specific phosphatase, has been shown to be involved in the mineralization
of the extracellular matrix in bone. It can hydrolyze phosphoethanolamine and phosphocholine to
generate inorganic phosphate, which is crucial for bone mineralization. Phospho1-/-mice show
hypomineralized bone and spontaneous fractures. All these data led to the hypothesis that
PHOSPHO1 is essential for bone mineralization and its structural integrity. However, no study to
our knowledge has shown the effects of PHOSPHO1 on bone fracture healing. In this study, we
examined how PHOSPHO1-deficiency might affect the healing and quality of the fractured bones in
Phospho1-/-mice.
Method: We performed rodded immobilised fracture surgery on the right tibia of control wild type
(WT) and Phospho1-/- mice (n=16 for each group) at eight weeks of age. Bone was left to heal for
four weeks and then the mice were euthanized and their tibias were analysed using Faxitron X-ray
analyses, microCT, histology and histomorphometry and three-point bending test.
Results: Our micro CT and X-ray analyses revealed that the appearance of the callus and several
static parameters of bone remodeling at the fracture sites were markedly different in WT and
Phospho1-/- mice. We observed a significant increase of BS/BV, BS/TV and trabecular number
and decrease in trabecular thickness and separation in Phospho1-/- callus in comparison to the
WT callus.These observations were further confirmed by histomorphometry. The increased bone
mass at the fracture sites of Phospho1-/- mice appears to be caused by increased bone formation
as there is a significant increase of osteoblast number, while osteoclast numbers remained
unchanged. There was a marked increase of osteoid volume over bone volume (OV/BV) in the
Phospho-/- callus. Interestingly, the amount of osteoid was markedly higher at the fracture sites
than that of normal trabecular bones. The three-point bending test showed that Phospho1 -/fractured bone had more of an elastic characteristics than the WT bone as they underwent more of
a plastic deformity before the breakage point compare to the WT.
Conclusion: Our work suggests that PHOSPHO1 plays an integral role during bone fracture
repair. PHOSPHO1 can be an interesting target to improve the fracture healing process.
5
CORA 05
A Randomized Controlled Trial Comparing Arthrographic Joint Injection with and without
Steroids for the Treatment of Adhesive Capsulitis
Allison Tucker, Queen’s University
Christina Hiscox, Ryan Bicknell
Purpose: Estimated to affect 2-5% of the population, adhesive capsulitis is a common cause of
shoulder pain and dysfunction. Many forms of treatment have been advocated including physiotherapy,
injection with steroid, distension arthrogram with steroid and/or local anaesthetic, manipulation under
anaesthetic and arthroscopic releases. The objective of this study is to determine if arthrographic
injection of the shoulder joint with steroid, local anaesthetic and contrast is an effective treatment
modality for adhesive capsulitis and whether it is superior to arthrographic injection with local
anaesthetic and contrast alone.
Method: This is a double-blinded randomized control trial of patients with a diagnosis of adhesive
capsulitis who were randomly assigned to receive an image guided arthrographic glenohumeral
injection with either triamcinolone (steroid), lidocaine (local anaesthetic) and contrast or lidocaine and
contrast alone. Outcome measures included active and passive shoulder range of motion and
functional outcomes assessed using the Shoulder Pain and Disability Index (SPADI), the Constant
Score and a Visual Analog Scale for pain. Post-operative evaluation occurred at 3 weeks, 6 weeks and
12 weeks. Descriptive statistics were utilized to summarize patient demographics and other study
parameters. One-way ANOVAs were used to compare VAS, Constant and SPADI scores across the
different time points for both study groups. The post hoc Bonferroni correction was used to adjust for
multiple comparisons.
Results: There were 37 shoulders injected with follow-up visits at 12 weeks. Twenty shoulders were
randomized to receive local plus steroid and 17 received local anaesthetic only. There were 21 females
and 14 males with an average age of 54 years (range, 42-70). VAS scores for both patient groups were
significantly improved (p<0.05) at all follow-up times. Goniometric testing demonstrated significant
improvements in forward flexion and internal rotation at 900 in the local group and only abduction in the
local plus steroid group. There were no significant changes in the Constant scores for the local group
(p=0.08), however the Constant scores showed significant improvement for the local plus steroid group
(p=0.003) at all follow-up time points. The local group showed significant improvement in their SPADI
pain scores at the 12 week follow-up only (p=0.01). There were no significant differences in their SPADI
disability scores (p=0.09). The local plus steroid group had significant improvement in SPADI pain and
disability scores at all follow-up time points (p=0.001).
Conclusion: The optimal treatment for adhesive capsulitis remains unclear. Our study demonstrated
that patients receiving an arthrographic injection of either steroid and local anaesthetic or local
anaesthetic alone had significantly improved post-injection pain scores. However, only the steroid and
local anaesthetic treatment group demonstrated improved SPADI disability and Constant scores.
Therefore, we believe that while either treatment is a good option for patients with adhesive capsulitis
and can reliably relieve pain, we would recommend the steroid with local anaesthetic as it may provide
improved function. In conclusion, arthrographic distension of the shoulder joint with steroid, local
anaesthetic and contrast is an effective treatment modality for adhesive capsulitis and is superior to
arthrographic injection with local anaesthetic and contrast alone.
6
CORA 06
The Imaging of Common Shoulder Disorders by the Primary Care Physician in British
Columbia
Geoff Jarvie, University of British Columbia
Jeffrey Pike, Danny Goel
Purpose: Shoulder pain is a common presentation to the primary care physicians (PCP). Patients
undergo initial evaluation by the PCP where the need for diagnostic imaging and subsequent
specialist referral is determined. The primary objective of this study was to investigate common
shoulder pathologies presenting to the PCP and to survey the appropriateness of imaging ordered
by PCP prior to specialist referral. Secondary objectives were accuracy of diagnosis by PCP and
wait times to see an orthopaedic surgeon.
Method: This study was a retrospective electronic chart review of 150 patients from a single
orthopaedic surgeon’s referral base. Inclusion criteria were patients between 18- 95 years of age
with a provisional diagnosis of rotator cuff tear (RCT), adhesive capsulitis (AC), glenohumeral
osteoarthritis (OA) and instability (I). Exclusion criteria were Workers’ Compensation Board or
Insurance Corporation of British Columbia patients. Appropriate shoulder imaging for each
pathology was guided by previously available literature and included: RCT (x-ray and US or MRI),
OA (x-ray), AC (x-ray) and I (x-ray). Inappropriate investigation was judged as the ordering of
imaging outside of accepted recommendations, unless other pathology was also suspected.
Results: The mean± standard deviation (range) age of the patients in the study was 56 ± 21 (20,
93), with a 1.3 male:female ratio. A detailed evaluation of the imaging ordered by PCPs revealed
shoulder pathology to be inappropriately investigated 25-50% of the time and appropriately imaged
40-74%, depending on the pathology of concern. The most common over-investigations included
MRI for OA/AC and ultrasound for I. The PCP correctly diagnosed the presenting shoulder
pathology as follows: RCT 59% (22/37), OA 56% (20/36), AC 21%(9/42) and I 97% (34/35). The
average wait time to see the orthopaedic surgeon was 138 ± 99 (17, 428) days.
Conclusion: This study demonstrates that for common shoulder pathology PCP have a low rate of
diagnostic accuracy and a high rate of over investigation. Rotator cuff related pathology, the most
common presenting cause of shoulder pain, was often referred as “shoulder pain not yet
diagnosed”. The lowest rate of diagnostic accuracy came for AC, with 21% of patients correctly
diagnosed. Unfortunately, AC was also accompanied by the highest rate of over investigation with
the most expensive imaging modality, MRI. Inappropriate or unnecessary investigations are costly
to the health care system, affect imaging wait times for all specialties and may delay treatment and
subsequent referral. The data highlights the need for improved PCP education around common
shoulder disorders. A focus on PCP education would potentially lead to improved patient care,
timely access to relevant imaging and specialist referral and decreased health care expenditure.
7
CORA 07
Characterization of Posterior Glenoid Bone Loss in Posterior Shoulder Instability
Jason J. Shin, University of Saskatchewan
Adam B. Yanke, Rachel M. Frank, Nikhil N. Verma, Brian J. Cole, Anthony A. Romeo, Matthew T.
Provencher
Purpose: Although glenoid bone loss has been well characterized in the setting of anterior
shoulder instability, little has been written in the literature in the setting of posterior instability. The
purpose of this study was to characterize the morphology and location of posterior glenoid bone
loss in patients with posterior instability utilizing computed tomography (CT).
Method: Clinical data was selected for patients with posterior shoulder instability that had
undergone posterior stabilization (open or arthroscopic) or posterior osseous augmentation (distal
tibia or iliac crest). The axial cuts were segmented and reformatted in three-dimensions for glenoid
analysis using Osirix software. From this three-dimensional model, the following was calculated:
percent bone loss (Nobuhara), total arc of the defect (degrees), glenoid version, and a clock-face
description (start point, stop point, and average of direction-all normalized to right shoulder).
Pearson correlation coefficients were performed using significance of p < 0.05.
Results: Forty-nine shoulders from 49 patients were reviewed. Twenty patients (average age 26.5
years; 95% males) had evidence of posterior glenoid bone loss and were included for evaluation.
Defects on average involved 13.7+/-8.6% of the glenoid (range, 2-3.5%). The average start time
(assuming all right shoulders) on the clock face was 10 o’clock +/- 40 minutes and stopped at 6:25
+/- 35 minutes. The average direction of the defect pointed towards 8:14 +/- 23 minutes. The
percent bone loss correlated with the total arc of the defect (Pearson: 0.93, p < 0.05, R^2:0.86).
The direction of bone loss moved more postero-superiorly, as the defect became larger (Pearson:
0.63, P < 0.05, R^2: 0.40).
Conclusion: Posterior bone loss associated with posterior glenohumeral instability is typically
directed posteriorly at 8:14 on the clock. As defect get bigger, this direction moves more
posterosuperiorly. This information will help guide clinicians in understanding the typical location of
posterior bone loss aiding in diagnosis, cadaveric models and treatment.
8
CORA 08
ACL Reconstruction Failure in Young Patients: A Gender Comparison
David Perrin, University of Manitoba
Jeff Leiter, Sheila McRae
Purpose: Anterior cruciate ligament reconstruction (ACLR) is one of the most commonly
performed procedures in sports medicine. Young athletes are sustaining anterior cruciate ligament
(ACL) injuries at alarming rates and young females are known to be at increased risk. Young age
appears to be a risk factor for ACLR failure, however very few studies have looked at the role of
gender in ACLR surgery outcomes. To our knowledge, no study has specifically compared gender
ACLR failure rates in young patients. The purpose of this study was to determine whether
differences existed between genders in ACLR failure rates in patients 20 years and younger.
Method: The study design was retrospective. Failure of ACLR was defined as revision surgery.
Data was extracted from a single centre’s electronic medical records database from August 2006
to May 2014. Data was analyzed using chi-square and t-test methods.
Results: 630 ACLR surgeries (female = 326, male = 304) were performed in the study time period
in patients less than 20 years of age. A total of 22 ACLR revision surgeries were performed (female
= 9, male = 13) for an overall revision rate of 3.5%. Period prevalence for ACLR revision was 2.8%
for females and 4.3% for males (p = 0.30). No differences were found between gender for average
age of revision surgery, associated meniscal tear or affected side.
Conclusion: ACLR revision rate did not differ based on gender in patients less than 20 years of
age. The overall revision rate in patients 20 years and under was 3.5%. This study shows that
young females do not have increased rate of ACLR failure despite known higher rates of ACL
ruptures. The focus should therefore be on ACL injury prevention in young females instead of
operative measures or rehabilitation protocols.
9
CORA 09
Short versus Long InterTAN Fixation for Geriatric Intertrochanteric Hip Fractures: A
Prospective, Multicentre Head-to-Head Comparison
Michael Sellan, Western University
Dianne Bryant, Christina Tieszer, Mark MacLeod, Steven Papp, Abdel Lawendy, Allan Liew, Darius
Viskontas, Chad Coles, Tim Carey, Wade Gofton, Andrew Ternholm, Trevor Stone, Ross Leighton,
David Sanders
Purpose: The benefit of using a long intramedullary device for the treatment of geriatric
intertrochanteric hip fractures is unknown. The InterTAN device (Smith and Nephew, Memphis TN)
is offered in either Short (180-200 mm) or Long (260-460 mm) constructs and was designed to
provide stable compression across primary intertrochanteric fracture fragments. The objective of
our study was to determine whether Short Inter TANs are equivalent to Long Inter TANs in terms of
functional and adverse outcomes for the treatment of geriatric intertrochanteric hip fractures.
Method: One hundred eight patients with OTA classification 31A-1 and 31A-2 intertrochanteric hip
fractures were included in our study and prospectively followed at one of four Canadian Level-1
Trauma Centres. Our primary outcomes included two validated primary outcome measures: the
Functional Independence Measure (FIM), to measure function, and the Timed Up and Go (TUG),
to measure motor performance. Secondary outcome measures included blood loss, length of
procedure, length of stay and adverse events. A pre-injury FIM was measured by retrospective
recall and all post-operative outcomes were assessed on post-operative day 3, at discharge, at 6
weeks, 3 months, 6 months and 12 months post-operatively. Unpaired t-tests and Chi-square tests
were used for the comparison of continuous and categorical variables respectively between the
Short and Long InterTAN groups. A statistically significant difference was defined as p<0.05.
Results: Our study included 71 Short InterTAN and 37 Long InterTAN patients with 31A-1 and
31A-2 intertrochanteric hip fractures. Age, sex, BMI, side, living status and comorbidities were
similar between the two groups. The mean operative time was significantly lower in the Short
InterTAN group (61 mins) as compared to the Long InterTAN group (71 mins)(p<0.05).
Functionally, the TUG was significantly (p<0.05) shorter in the Long InterTAN group despite having
similar FIM total scores at one year. Pre- and post-op hemoglobin values and transfusion rates
were similar for the two groups. The average length of stay was 16.2 days for the Long InterTAN
group and 19.9 days for the Short InterTAN group (p>0.05). There were five periprosthetic femur
fractures in the short InterTAN group versus one in the long InterTAN group. Non-mechanical
adverse outcomes such as myocardial infarction, pulmonary embolism, urinary tract infections,
pneumonia and death all had similar incidence rates between the two InterTAN groups.
Conclusion: Both the Short and Long InterTAN patient cohorts displayed similar improvements in
performance and overall function following intertrochanteric hip fracture fixation over a 12 month
period. The recorded operative times for Short InterTAN fixation were significantly shorter than
those recorded for the Long InterTAN patients. Alternatively, a significantly higher proportion of
Short InterTAN patients sustained periprosthetic femur fractures within a year of implantation as
compared to the Long InterTAN group.
10
CORA 10
Kinematically Aligned Total Knee Arthroplasty is Associated with Lower Knee Adduction
Moment than Knees Aligned to Neutral Mechanical Axis
David A.J. Wilson, Dalhousie University
Janie L. Astephen Wilson, Glen Richardson, Michael J. Dunbar
Purpose: It has been proposed that by recreating a patient’s native knee joint line in total knee
arthroplasty surgery, (ie. kinematic alignment), the patient can achieve improved functional outcome
and greater satisfaction. Although early outcome studies of kinematic alignment techniques have been
generally positive (Rebal et al. 2014), historically varus alignment has been associated with increased
risk of early implant failure. The knee adduction moment has been shown to be a surrogate for loading
at the knee joint (Kutzner et al. 2013), and we have shown previously that high knee adduction
moments during walking gait are associated with high early migration of the tibial component and tilt
into further varus after surgery (Astephen-Wilson 2010).
The purpose of this study was to compare the knee adduction moment during walking gait at one year
post-surgery of a cohort of patients, half who had primary total knee arthroplasty performed with a goal
of neutral mechanical alignment, and half with virtual gap balancing (i.e. kinematic alignment). We
hypothesized that the kinematic alignment group would have a higher knee adduction moment and may
be at risk of early failure due to higher medial compartment dynamic forces on the prosthesis.
Method: A navigated surgery version of the kinematic alignment technique was adopted as standard of
care by two participating surgeons in 2011. The surgical navigation system was used to perform virtual
gap balancing for the bony resections with the objective of minimizing soft tissue releases and
optimizing flexion extension balance. This typically resulted in a varus tibial cut, an internally rotated
femur and an overall varus alignment. Between 2009 and 2011, the surgical navigation system was
used by the same surgeons to achieve neutral mechanical alignment. Twenty-four (12 neutral and 12
kinematic) underwent three-dimensional gait assessment at one year post-op. Principal component
analysis was used to capture the overall magnitude and pattern of the knee adduction moment during
gait. The principal component scores of the knee adduction moment were compared between the two
groups using a t-test.
Results: There were no statistically significant differences between the groups in demographics. Postoperatively, the kinematical alignment group had significantly lower overall magnitudes of the knee
adduction moment during gait measured as PC1 (P=0.016), and significantly more ‘unloading’ of the
knee adduction moment mid-stance relative to early stance as measured by PC2 (P=0.028), indicative
of an improvement in knee joint function.
Conclusion: The results of this study showed that varus tibial component positioning and overall varus
alignment were not associated with increased adduction moment during gait. On the contrary, the
kinematic alignment group had significantly lower knee adduction moments during gait, as well as an
improved ability to ‘unload’ the medial compartment mid-stance during weight acceptance, a pattern
characteristic of healthy gait (Astephen et al. 2008). This represents one of the first indications that
appropriately balanced knees in varus alignment do not have increased loading during dynamic use
and therefore do not have higher risk of subsequent failure due to higher dynamic loading.
11
CORA 11
The Effect of Varying Tension of a Suture Button Construct in Fixation of the Tibiofibular
Syndesmosis - Evaluation Using Stress Computed Tomography
John Morellato, University of Ottawa
Hakim Louati, Andrew Bodrogi, Andrew Stewart, Steve Papp, Allan Liew, Wade Gofton
Purpose: Suture button fixation has been shown to have decreased syndesmosis malreduction rates
however there have been no studies assessing the optimal biomechanical tension of these constructs. The
purpose of this study was to assess optimal tensioning of suture button fixation and its ability to maintain
reduction under loaded conditions using a novel stress computed tomography (CT) model.
Method: Ten cadaveric lower limbs disarticulated at the knee were used. The limbs were placed in a
modified external fixator jig that allows for the application of sustained torsional (5 newton meters, Nm), axial
(500 newtons, N) and combined torsional/axial (5Nm/500N) loads. Baseline unloaded and loaded CT scans
were obtained. The syndesmosis and the deep deltoid ligament complex were then sectioned. The limbs
were then randomized to receive a suture button construct tightened at 4 kg force (loose) or 8 kg (standard)
or 12 kg (maximal) of tension.
Seven previously validated measurements and two angles were taken from the axial CT scans. These
included measures of medial-lateral translation (measurements ML and C) a measure of anterior-posterior
translation (measurements AP, D, and E, and D/E ratio), and two angles; one angle (Angle 1) created by a
line parallel to the incisura and the axis of the fibula and a second angle (Angle 2) created by the inner
surfaces of the malleoli at the level of the tibiotalar joint (Figure 1). Each measurement was taken at
baseline and compared with the three loading scenarios.
Results:
Posterolateral Translation
Under all fixation tensions, posterolateral fibular translation was observed (measurement A). This was
maximal with the 4 kg fixation with the application of combined loading conditions (6.84 mm). Measurement
B, measured at the posterior incisura, did not show any differences in the loaded conditions.
Medial/Lateral translation
Under torsional loading, 5.03mm and 5.23mm of lateral translation of the fibula was observed (ML and C
respectively). This was only observed with 4 kg fixation only.
With the 12 kg tension fixation without load, medial translation (ML=1.69mm) of the fibula was observed
signifying over compression.
Anterior/Posterior Translation
Significant posterior translation was observed across all fixation tensions under torsional and combined
loading (AP and D/E) with a maximum value of 6.42mm in the 4 kg repair.
Rotation
Under combined loading conditions, significant external rotation was observed as measured by Angle 1,
with the 4 kg and 8 kg tension repair of 9.25° and 10.80° respectively. There was no significant rotation seen
with the 12 kg repair. Significant external rotation was also observed as measured by Angle 2 with torsional
loading with the 4 kg repair only (11.71°) There were no significant differences with respect to the 8 kg and
12 kg fixation.
Conclusion: Suture button constructs must be appropriately tensioned to maintain reduction and reapproximate the degree of physiological motion at the distal tibiofibular joint. These constructs also
demonstrate over compression of the syndesmosis however the clinical effect of this remains to be
determined.
12
CORA 12
Practice Patterns in the Care of Acute Achilles Tendon Ruptures: Is There an Association
with Level I Evidence
Ujash Sheth, University of Toronto
David Wasserstein, Richard Jenkinson, Rahim Moineddin, Hans Kerder, Susan Jaglal
Purpose: Over the last decade, there has been a growing body of level I evidence supporting the
‘functional’ non-operative management (i.e., early range of motion and early weight bearing) of
acute Achilles tendon ruptures. Despite this emerging evidence, there have been very few studies
evaluating its uptake. Our primary objective was to determine whether the findings from a landmark
Canadian trial assessing the optimal treatment strategy for acute Achilles tendon ruptures
influenced the practice patterns of orthopaedic surgeons in Ontario, Canada over a 12-year time
period. As a second objective we examined whether patient and provider predictors of surgical
repair utilization differed before and after dissemination of the landmark trial results.
Method: Using provincial health administrative databases, we identified Ontario residents ≥ 18
years of age with an acute Achilles tendon rupture from April 2002 to March 2014. The proportion
of surgically repaired ruptures was calculated for each calendar quarter and year. A time series
analysis using an interventional autoregressive integrated moving average (ARIMA) model was
used to determine whether changes in the proportion of surgically repaired ruptures were
chronologically related to the dissemination of results from a landmark Canadian trial by Willits et
al. (first quarter, 2009). Spline regression was then used to independently identify critical timepoints of change in the surgical repair rate to confirm our findings. A multivariate logistic regression
model was used to assess for differences in patient (baseline demographics) and provider (hospital
type) predictors of surgical repair utilization before and after the landmark trial.
Results: From the second quarter of 2002 to the first quarter of 2010 the surgical repair rate
remained constant at ~21%, however, by the first quarter of 2014 it fell to 6.5%. A statistically
significant decrease in the rate of surgical repair (P<0.001) was observed after the results from a
landmark Canadian trial were presented at a major North American conference (February 2009).
Both teaching and non-teaching hospitals demonstrated a decline in the surgical repair rate over
the study period, however, only the decrease seen at non-teaching hospitals was found to be
significantly associated with the dissemination of landmark trial results (P<0.001). All other
predictors of surgical repair utilization remained unchanged in the before-and-after analysis with
the exception of patients  30 years of age having a higher odds of undergoing surgical repair after
the trial when compared to those  51 years of age.
Conclusion: The current study demonstrates that large, well-designed randomized trials, such as
the one conducted by Willits et al. can significantly change the practice patterns of orthopaedic
surgeons. Moreover, the decline in surgical repair rate observed at both teaching and non-teaching
hospitals suggests both academic and non-academic surgeons readily incorporate high quality
evidence into their practice.
13
CORA 13
IL-17F is Upregulated During Osteogenesis in Human Fracture Repair
Andrea H.W. Chan, University of Toronto
Yufa Wang, Diane Nam
Purpose: The pro-inflammatory cytokine IL-17F, secreted by T-lymphocytes, is a key mediator in the
immune response that occurs during fracture healing. The signaling pathway by which IL-17F promotes
osteogenesis in the human fracture population has not been clearly elucidated. IL-17F was previously
shown to upregulate the expression of mature bone markers in a healthy murine fracture model to increase
capacity for osteoblast differentiation and promote earlier mineralization with more advanced remodeling
characteristics. This upregulation, however, was diminished in T-cell deficient mice and correlated with
impaired fracture healing. We hypothesize that human IL-17F is similarly upregulated during the early phase
of normal fracture repair and may function as a key biomarker of bone healing. Our specific aims are to: 1)
demonstrate that human pre-osteoblast cells, when treated with IL-17F, show increased expression of
osteoblast bone markers known to be involved in fracture healing; 2) demonstrate that human IL-17F
expression in fracture hematoma is upregulated post-fracture compared to controls; 3) assess the impact
that injury severity score (ISS), sex and time since injury has on the local inflammatory milieu of the fracture
hematoma; and 4) determine whether or not a decrease in IL-17F translates to impaired or delayed
radiographic fracture union.
Method: Osteoblast culture: A human pre-osteoblast cell line was treated with exogenous IL-17F. Total
RNA extraction and quantitative real-time PCR (qPCR) were performed for osteoblast bone markers known
to be involved in fracture healing. Hematoma analysis: Fracture hematoma was collected intraoperatively
from 31 patients who had sustained long bone fractures. Total RNA extraction and qPCR were performed
for cytokine markers known to be involved in fracture healing. Controls: Long bone samples were collected
from eight healthy control patients undergoing elective orthopaedic surgery procedures. Total RNA
extraction and qPCR were performed for the same cytokine markers. Analysis: Student t-tests were used to
calculate statistical differences, and a p-value of <0.05 was considered significant.
Results: Preliminary results are presented for the first three aims.
1) IL-17F stimulation of human pre-osteoblast cell line cultures demonstrated a trend towards
increased RNA expression of known markers of osteoblast cell maturation, namely ALP, BMP-2, BMP-4,
Col1, Col2, BSP, Runx2 and osteocalcin, when compared to control cell lines.
2) Quantitative RT-PCR analysis of fracture hematoma demonstrated that IL-17F was significantly
increased when compared to controls (p=0.03).
3) While not significant, males and patients with ISS > 15 showed increased levels of IL-17F (p=0.13,
p=0.84 respectively). Time since injury (<72hrs vs. >72hrs) did not appear to have a significant impact
on IL-17F levels (p=0.32).
Conclusion: The current study presents preliminary results of a larger study. These demonstrate that IL17F upregulates bone markers involved in osteoblast maturation, and is present in significantly higher levels
in human fracture hematoma. These results suggest that IL-17F may play a crucial role in the osteoblast
maturation during human fracture repair. Further work is needed to elucidate its exact signaling pathway. IL17F may prove to be an important therapeutic immune target for the promotion or prediction of fracture
union in the trauma patient.
14
CORA 14
Proficiency-based Arthroscopic Curriculum (PAC): A Self-directed,
Psychomotor Training Tool for Medical Students
Ryan P. Coughlin, McGill University
Gabriel B. Roby, Thierry Pauyo, Jonathan Doyon, Stéphane G. Bergeron
Personalized
Purpose: There has been a recent effort to incorporate medical simulation models into
structured educational curricula in response to ongoing concerns over work hour restrictions,
patient safety and the impact of fellowship training on residency education. As surgical education
moves towards a more flexible learning timeframe, focused on personalized skill development,
training programs will need to establish clearly defined targets for acquiring competency. The
purpose of this study was to design a proficiency-based curriculum for trainees to develop basic
arthroscopic psychomotor skills using a validated simulation box model.
Method: Medical students from a single institution were recruited and assigned to either the
proficiency-based arthroscopic curriculum (PAC) group or the control group. Subjects completed a
survey on demographics and previous arthroscopic experience. After watching a short orientation
video, all participants underwent a baseline evaluation. Subjects performed six basic arthroscopic
tasks using a validated box model: (1) probing, (2) grasping, (3) tissue resection (4) tissue shaving,
(5) tissue liberation, and (6) knot-tying. A total global score, of a possible 100 points, was
calculated by averaging scores from all six tasks using equal weights. The PAC participants were
given access to instructional videos as well as unlimited, self-directed practice sessions with
proficiency standards for each task. Proficiency targets were specific to each task, and included a
maximum time to completion and number of mistakes allowed. PAC participants were evaluated
once they achieved proficiency in all tasks. The control group was evaluated eight weeks after the
baseline evaluation. Performance was scored by a blinded trained reviewer, and was based on
video recordings and material collected from certain tasks.
Results: A total of 33 medical students were recruited. Twenty-two participants were enrolled in
the proficiency-based curriculum (PAC) and 16 completed the study (73%). Eleven participants
were enrolled in the control group and 10 completed the study (91%). The baseline characteristics
for all participants were similar, except year of study in medical school (p=0.007). The mean
number of hours practiced by the PAC group was 4.8 hours (±2.6). The mean baseline total global
scores for the PAC group (10.8 ±7.3) and the control group (10.5 ±8.1) were not significantly
different (P=0.92). The mean final global scores of the PAC group (51.6 ±19.2) were significantly
greater compared to the control group (21 ±8.8) (p<0.0001). Using multivariable linear regression,
hours of practice, female sex, and right hand dominance were found to be independent predictors
of improvement in total global score for the PAC group.
Conclusion: We successfully designed a proficiency-based curriculum with clearly defined
arthroscopic skill targets that can be used to guide progression in the motivated learner.
Participants who completed the proficiency-based arthroscopy curriculum showed significantly
greater improvement in psychomotor skill performance compared to participants who did not
complete the curriculum.
15
CORA POSTER ABSTRACTS
CORA P01
Follow-up after Primary Total Knee Arthroplasty: A Cost-utility Analysis
Daniel Pincus, University of Toronto
Eric Crawford, Richard Jenkinson, Hans Kreder, Beate Sander, William L. Wong
Purpose: Orthopaedic surgeons have questioned the usefulness of annual follow-up after total knee
arthroplasty (TKA). However, no established standard of care for follow-up after TKA exists. We sought
to examine the cost-utility of annual follow-up after primary TKA compared to no follow-up.
Method: We performed a cost-utility analysis of annual follow-up for up to 15 years post-TKA
compared to no follow-up from the perspective of Ontario’s single-payer healthcare system. The first
year post-TKA was excluded from the analysis to permit early post-operative follow-up in either
strategy.
We developed a Markov model to estimate expected post-TKA health outcomes, quality-adjusted life
years (QALYs), and costs ($CAN), discounted at 5%. Our base case was the average Canadian TKArecipient; a 67-year-old with end-stage knee osteoarthritis. We considered five health states: primary
TKA, undiagnosed failure, diagnosed failure, revision TKA and death. Post-operative follow-up had the
benefit of early detection and intervention but incurred costs of diagnostic tests and physician services.
Delayed revision surgery resulted in adverse health outcomes (longer rehabilitation) and additional
costs (more expensive prostheses). We derived probability, utility and cost data from the literature.
Deterministic sensitivity analyses assessed uncertainty and several important clinical scenarios were
modeled, including: age, gender, surgeon volume, implant choice, arthritis type, and after revision.
Results: Fifteen years post-TKA, the majority of the cohort still had their original primary TKA (59.6%)
or had died (35.0%), translating into expected QALYs of 7.6036 and 7.6012 for annual follow-up
compared to no follow-up. Corresponding expected costs were $92,383 and $91,947 for annual followup and no follow-up. While annual follow-up was more effective (0.0022 QALYs gained), it was also
more expensive ($421) than no follow-up, resulting in an incremental cost of $191,363 per QALY
gained.
The cost-utility of follow-up was most sensitive to the overall failure rate and the proportion of
asymptomatic failures. However, follow-up was only favored in sensitivity analyses when failure rates
and the proportion of asymptomatic failures were high and outside the clinically observed range. Annual
follow-up was not cost-effective at a threshold of $50,000 per QALY gained for any age, gender,
surgeon volume, implant chosen, or arthritis type, except after revision.
Conclusion: Long-term annual follow-up was not cost-effective from the healthcare payer perspective
since revision is rare and associated with symptoms that prompt patients to seek medical attention
regardless of follow-up. Therefore, in the absence of patient symptoms that necessitate ongoing care,
we suggest that orthopaedic surgeons in Ontario perform no routine annual follow-up for patients
between 1-15 years after primary TKA. In the future, we intend to examine the cost-utility of other
follow-up algorithms after TKA as well after other orthopaedic procedures with low failure rates.
16
CORA P02
Cost Consequence Analysis of Implementing the SickKids Paediatric Orthopaedic Pathway
(SKPOP) for Proximal Humerus Fractures in Ontario, Canada
Eric Crawford, University of Toronto
Daniel Pincus, Mark Camp
Purpose: The vast majority of paediatric proximal humerus fractures are managed non-operatively with
minimal intervention and without complication. Despite the success of minimal intervention, however,
close follow-up and repeat radiographic assessments comprise traditional non-operative care for these
injuries.
The XPaediatric Orthopaedic Pathway (XPOP) for proximal humerus fractures was developed to
simplify follow-up and radiographic assessments for patients with these injuries. The main objective of
this study was to examine the cost savings associated with implementing this pathway in Ontario,
Canada from the perspective of Ontario’s Ministry of Health and Long-term Care (MOHLTC – a single
payer healthcare system).
Method: The economic analysis was from the perspective of the MOHLTC and direct healthcare costs
were included. Children with simple proximal humerus fractures presenting to our institution between
2009-2014 were included. Fractures associated with bone cysts or pathological lesions, open or
multiple fractures or associated neurovascular injuries, were excluded.
Costs considered included orthopaedic assessments, shoulder radiographs and radiologist fees (2015
values, Canadian dollars). Based on prior research, we assumed that the XPOP investigated was as
clinically effective as traditional follow-up. Resource profiles were created for each patient with a
proximal humerus fracture presenting to our institution between 2009-2014; based on actual follow-up
assessment values versus follow-up assessments according to the XPOP for proximal humerus
fractures. Differences between the two strategies represent the potential resource and cost savings
expected after XPOP implementation.
Results: Two hundred and twenty patients (92.9%) were eligible for management according to the
XPOP for proximal humerus fractures. For eligible patients, the XPOP would have resulted in 83.6%
less orthopaedic assessment visits and 70.8% fewer radiographic series; yielding a cost minimization of
$30,040.56 for this cohort (or $135.32 per patient). Only one patient (an eight-year-old male with 100%
fracture displacement), who had surgery at the time of initial presentation, would have been eligible for
non-operative treatment according to the XPOP for proximal humerus fractures.
Based on annual incidence rates of simple paediatric proximal humerus fractures in Ontario, the
MOHLTC would expect to save at least $77,815.90 annually following XPOP implementation provincewide.
Conclusion: Implementation of the XPOP for proximal humerus fractures in Ontario would be expected
to save Ontario’s MOHLTC at least $77,815.90 per year (or $135 per patient), with assumed equivalent
effectiveness of traditional care. For this reason, we recommend that Ontario’s MOHLTC establish
formal policy endorsing the XPOP for paediatric proximal humerus fractures. Widespread
implementation of the XPOP for proximal humerus fractures in other jurisdictions may lead to similar
reductions of unnecessary radiographs, follow-up assessments and costs. Future research should
include prospective study designs that report actual cost savings and patient-based functional
outcomes measures or utilities for XPOP implementation.
17
CORA P03
External Validation of the French Version of the Discharge of Hip Fracture Patients Score
Emanuelle Villemaire-Côté, Université Laval
Stéphane Pelet
Purpose: This paper reports the external validation of the French version of the Discharge of Hip
fracture Patients score (DHP), a recent score that predicts discharge location on admission in
patients living in their own home prior to hip fracture surgery. This score was developed and first
validated in The Netherlands.
Method: French translation of the DHP was realised according to AAOS guidelines. The score was
introduced in our level one trauma centre in a prospective cohort study describing long-term
discharge patterns after hip fracture. One hundred and fifty eight (158) patients were enrolled in the
study and 116 patients met the selection criteria for this trial. Patients characteristics were
described. Sensitivity, specificity, positive and negative predictive value (PPV, NPV), ROC curve
(and area under the curve (AUC)) were calculated and compared to the original Dutch cohorts
(Delft and Groningen).
Results: Sixty-five patients (56%) were discharged to an alternative location (DAL) than their own
home, with a DHP (mean ± SD) of 29.8 ± 12.3 (vs 50.6 ± 16.6, p˂0,01). These patients were older
(83.8 years ± 6.9 vs 73.7 ± 7.7, p˂0,01), had an altered mental status (MMSE˂25 46.2% vs 13.7%,
p˂0,01), lived alone (80% vs 51%, p˂0,01) and had a lower pre-fracture level of mobility (55.4%
used an aid vs 11.8%, p˂0,01) than patients discharged to their own home.
Sensitivity of the DHP for DAL is higher in this cohort (91.7% vs Delft 83.8% and Groningen 75%).
Same results for specificity (68.5% vs 64.7% and 66.6%) and NPV (96.9% vs 71.3% and 48.9%),
but lower PPV (43.1% vs 79.2% and 86.3%). ROC curve has a very good AUC compared to Dutch
cohorts: 0,87 (95% CI 0,73-0,95) vs 0,84 (0,79-0,88) and 0,75 (0,66-0,82). Interestingly, DHP ≥ 30
is associated with a longer hospital stay (21.8 days ± 17.8 vs 10.8 ± 6.3, p˂0,01).
Conclusion: The external validation of the French version of the DHP is successful. The score
accurately predicts discharge location of hip fracture patients with excellent sensitivity, specificity,
NPV and AUC. PPV was lower than in Dutch cohorts according to significant differences in age
and mental status between the cohorts.
The DHP score is a valid instrument for general hip fracture population in both French and English
versions. The general use of DHP could result in reduced socio-economic costs related to hip
fractures in developed countries.
18
CORA P04
Rate of and Risk Factors for Reoperation after Open Reduction and Internal Fixation of Ankle
Fracture: A Population Based Study
Thomas Zochowski, University of Toronto
David Wasserstein, Darrell Ogilvie-Harris, Johnny Lau, Nizar Mahomed, Andrea Veljkovic
Purpose: Ankle fracture is a common orthopaedic injury and following open reduction and internal
fixation [ORIF] there are numerous acute and chronic complications that may result in reoperation
including, hardware irritation, failed fixation, infection, and post traumatic arthritis resulting in ankle
fusion or arthroplasty. Neither the rates of reoperation, nor the factors that predict reoperation are clear
in the current literature. We sought to establish baseline rates of and risk factors for reoperations
following ankle fracture ORIF in a large population cohort.
Method: Administrative databases were used to identify patients >16 years of age who presented to
hospital with an ankle fracture from January 1994 to March 2013 in Ontario, Canada. The primary
outcome was reoperation (short term - repeat of index event, implant removal, irrigation and
debridement [deep infection], amputation; long term - fusion and arthroplasty). A multivariable logistic
regression analysis was performed to determine the influence of patient, provider and surgical factors
on the short term outcomes. The rates of ankle fusion and arthroplasty at ten years were established
using Kaplan-Meier survival analysis.
Results: We identified 45,444 patients who underwent ORIF of ankle fracture (mean age, 48 years (±
19 years); 41.2% male). One in five patients (20.2%) underwent at least one subsequent operation. The
most common procedure was isolated ankle implant removal (18.7%), with the odds of removal higher
for females (odds ratio [OR], 1.43; 95% confidence interval [CI], 1.36, 1.52 p<0.001). The median time
to implant removal was 12 months. Early reoperation for repeat ORIF, deep infection and amputation
occurred in 0.4%, 0.4% and 0.1% of the patients after a median of one, three and four months
respectively. The odds of repeat ORIF and surgical debridement for infection were greatest for open
fractures (OR 2.2; 95% CI 1.24, 3.94; p<0.001 and OR 3.2; 95% CI 1.97, 5.11; p<0.001). The odds of
amputation was highest for diabetics (OR 7.3; 95% CI 3.56, 15.31; p<0.001).
Event-free survivorship to ankle fusion was 0.9941 (i.e., 0.59% incidence rate of fusion) and ankle
arthroplasty 0.9984 (i.e., 0.16% incidence rate of arthroplasty) at ten-years. At ten years the slope of
the Kaplan Meier curves were still negative (i.e., incidence rate of fusion or arthroplasty constant).
Conclusion: In conclusion, one in five patients underwent reoperation within two years after ankle
fracture ORIF. The most common reoperation was isolated ankle implant removal which was more
likely in females. The incidence of repeat ORIF, deep infection and amputation were low, but the odds
of requiring one of these procedures increased significantly in patients who had a previous diagnosis of
diabetes or who presented with an open fracture. Although rates of fusion and arthroplasty are low at
ten-years overall, the shape of the survival curves suggests that the risk of this outcome remains
constant even after 10 years follow-up – for a young patient this may be a considerable life-time risk
(i.e., a 20 year old post ORIF who has an estimated lifespan of 75 years). The burden of post-traumatic
arthritis of the ankle post-ORIF cannot be assessed in this sample.
19
CORA P05
Too Much for Too Little: Cost Analysis of Current Total Hip Arthroplasty Follow-up
Practices
Chris Small, Memorial University
Andrew Furey
Purpose: Total hip arthroplasty (THA) is a common and extremely beneficial procedure that is
being performed more often as the population ages. Current THA follow-up guidelines require large
amounts of resources and may not justify their cost with increased patient outcomes. Most
problems that would require THA revision will cause symptoms. Late-presenting asymptomatic
THAs that are found to require revision are complicated and expensive to address and often lead
to poor patient outcomes. Follow-up visits for THA patients are essentially a screening tool to
identify asymptomatic THAs that require revision. The rate of asymptomatic THA revision and the
subsequent cost of screening for them is not well reported in the literature. Given the relative
shortage of orthopaedic resources, efficient use of clinic time should be a priority and inefficient
practices should be identified and changed.
Method: We calculated the rate of asymptomatic hip revisions over the first 20 years of THA
ownership. We further calculated the cost of a single visit to the orthopaedic clinic for follow up of a
THA. Finally, we calculated the cost savings of decreasing the follow-up schedule to a total of three
visits.
Results: The cost savings of foregoing the screening to identify one asymptomatic THA requiring
revision is CAD $1.2 million.
Conclusion: Asymptomatic THAs requiring revision are rare and, as such, require a large amount
of follow up to diagnose. As a screening tool, regular orthopaedic follow up of THA is an inefficient
use of resources. Current follow-up guidelines are cost-prohibitive and should be made much less
frequent in order to save resources.
20
CORA P06
The Design, Engineering, and Experimental Testing of a Novel Medial Portal ACL Guide: An
Anatomic Study
Daniel Banaszek, Queen’s University
Michael Pickell, Daniel Hesse, Manuela Kunz, Davide Bardana
Purpose: Current trends in surgical technique of ACL Reconstruction favor anatomic positioning of the
ligament’s insertion sites, in order to restore native knee function. Specifically, the medial portal
technique, whereby the ACL femoral tunnel is drilled through an accessory anteromedial portal (AMP)
allows consistent anatomical ACL tunnel placement. Studies comparing anteromedial to transtibial (TT)
techniques have identified the latter as having an increased likelihood of instability symptoms
secondary to a pivot-shift phenomenon from a vertically oriented graft. Previous research has been
directed at directly comparing commercially-available femoral guides in terms of footprint accuracy,
optimal tunnel length, and tunnel angle. No guide proved superior in the evaluation of footprint accuracy
in this study. Flexible pin guides demonstrated improvement with regards to tunnel length and tunnel
angle. As a result, our group set out to design a guide with reproducible tunnel placement on the femur,
via surface mapping triangulation. We hypothesize our novel idea will prove superior with regards to
accurate tunnel placement when compared to immediately available guides.
Method: Using a human cadaveric femur, the mathematical centre of the ACL femoral attachment was
determined to be the anatomically ideal location for femoral tunnel placement. The equivalent position
was marked on an artificial femur model (Sawbones®). Through surface matching Computer
Tomography (CT) metrics, a novel tunnel guide was designed and engineered in conjunction with a
local machine shop (Wejay Machine Products®). Five orthopaedic surgeons performed arthroscopic
femoral tunnel pin placement onidentical artificial Sawbones® femurs using our novel guide through an
anteromedial portal. Data was compared to iterations of the five commercially available guides. Tunnel
placement was quantitatively compared to the ideal position using virtual Computer Tomography (CT)
reconstruction. Outcome data was collected with respect to 1) distance from ideal position, 2) tunnel
length, and 3) tunnel angle.
Results: Of the five tested commercially-available femoral guides, the Stryker® VersiTomic® proved to
have both the greatest accuracy (distance from ideal footprint) at 3.9mm, as well as the most optimal
tunnel length at 33.4mm. Overall, the two flexible pin systems (Stryker and Smith & Nephew) proved to
be the two most accurate guides. There is no statistical difference, however, between tools in terms of
accuracy (p=.05). Only 8/125 (6.4%) iterations were within our set acceptable limit of 2mm from the
ideal footprint. In terms of tunnel length, 85/125 (68%) of iterations fell within our set limit of 31.857+/5mm from ideal.
When compared to commercially available guides, our novelty tool displayed statistically significant
improvement in terms of accuracy of femoral tunnel placement across all users (p<.05). Tunnel length
was significantly improved over straight reamer systems, and equivalent to flexible-guide systems.
Conclusion: Although current trends in orthopaedic sports medicine call for anatomic reconstruction of
the ACL, there is tremendous variability with respect to femoral tunnel positioning with currently
available arthroscopic guides. Based on anatomic triangulation, our group has designed a femoral
guide which is more accurate than what is currently available commercially. Further complementary
research is needed both in cadaveric models, and human subjects to fully elucidate anatomic accuracy
and applicability to the operating room.
21
CORA P07
Optimal Seeding Densities for in vitro Chondrogenesis of Two and Three Dimensional-isolated
and Expanded Bone Marrow-derived Mesenchymal Stromal Stem Cells within a Porous Collagen
Scaffold
Troy D. Bornes, University of Alberta
Nadr M. Jomha, Aillette Mulet-Sierra, Adetola B. Adesida
Purpose: Bone marrow-derived mesenchymal stromal stem cells (BMSCs) are a promising cell source
for treating articular cartilage defects. BMSCs seeded within biomaterial scaffolds and implanted into
focal chondral defects are capable of resurfacing cartilage in animal and human joints, although
inconsistent outcomes have been reported based on macroscopic assessment, histological analysis,
magnetic resonance imaging and clinical scoring. Repair tissue quality has been shown to correlate
with functional outcome following transplantation. Therefore, tissue-engineering variables, such as cell
expansion environment and seeding density of scaffolds, are currently under investigation with the goal
of improving neo-cartilage quality. The objectives of this study were to demonstrate chondrogenic
differentiation of BMSCs seeded within a collagen I scaffold following isolation and expansion in twodimensional (2D) and three-dimensional (3D) environments, and assess the impact of seeding density
on in vitro chondrogenesis. It was hypothesized that both expansion protocols would produce BMSCs
capable of hyaline-like chondrogenesis with an optimal seeding density of 10 million cells/cm 3.
Method: Ovine BMSCs were isolated in a 2D environment by plastic adherence, expanded to passage
two in flasks containing expansion medium, and seeded within cylindrical collagen I scaffolds (6 mm
diameter, 3.5 mm thickness and 0.115 ± 0.020 mm pore size; Integra LifeSciences Corp.) at densities
of 50, 10, 5, 1, and 0.5 million BMSCs/cm 3. For 3D isolation and expansion, bone marrow aspirates
containing known quantities of mononucleated cells (BMNCs) – a small fraction of which were BMSCs
– were seeded on scaffolds at 50, 10, 5, 1, and 0.5 million BMNCs/cm 3 and cultured in expansion
medium for an equivalent duration to 2D expansion. All cell-scaffold constructs were differentiated in
vitro in chondrogenic medium containing transforming growth factor-beta three for 21 days and
assessed with reverse-transcription quantitative polymerase chain reaction (RT-qPCR), safranin O
staining, histological scoring using the Bern Score, collagen immunofluorescence, and biochemical
quantification of glycosaminoglycan (GAG) and deoxyribonucleic acid (DNA).
Results: Two dimensional-expanded BMSCs seeded at all densities were capable of proteoglycan
production and displayed increased expressions of aggrecan and collagen II mRNA relative to predifferentiation controls. Collagen II deposition was apparent in scaffolds seeded at 0.5-10 million
BMSCs/cm3. Chondrogenesis of 2D-expanded BMSCs was most pronounced in scaffolds seeded at 510 million BMSCs/cm3 based on aggrecan and collagen II mRNA, safranin O staining, Bern Score, total
GAG, and GAG/DNA. For 3D-expanded BMSC-seeded scaffolds, increased aggrecan and collagen II
mRNA expressions relative to controls were noted with all seeding densities. Proteoglycan deposition
was present in scaffolds seeded at 0.5-50 million BMNCs/cm3, while collagen II deposition occurred in
scaffolds seeded at 10-50 million BMNCs/cm3. The highest levels of aggrecan and collagen II mRNA,
Bern Score, total GAG, and GAG/DNA occurred with seeding at 50 million BMNCs/cm 3.
Conclusion: BMSCs expanded in 2D and 3D environments are capable of hyaline-like chondrogenesis
within a collagen I scaffold. Optimal seeding densities appear to be 5-10 million BMSCs/cm3 and 50
million BMNCs/cm3 for 2D and 3D expansion protocols, respectively. Accordingly, these densities could
be considered when seeding collagen I scaffolds in BMSC transplantation protocols.
22
CORA P08
Clinical Impact of Shortening of the Clavicle after Conservative Treatment of Fractures in
the Middle Third
Simon Corriveau-Durand, Université Laval
Amerigo Balatri, Stéphane Pelet, Mathieu Boulet
Purpose: There is no clear consensus regarding the indications for surgical treatment of middle
third clavicle fractures. An initial shortening of two centimetres (cm) or more of the clavicle was
associated with poor clinical outcomes and a higher rate of non-union. In recent literature, the
number needed to treat (NNT) clavicle fractures in order to prevent non-union ranges from four to
nine. A direct relationship between shortening of the clavicle and a poor clinical outcome has not
yet been demonstrated.
Method: A prospective cohort study was performed in a level one trauma centre including 148
clavicle fractures treated conservatively. Eighty-five patients met the inclusion criteria (healed
fracture in the middle third, no other upper limb lesions) and 63 were enrolled. A single assessment
was realised at a minimum one year follow-up by an independent examiner and consisted in
Constant and DASH scores, range of motion, strength in abduction (Isobex) and a specific
radiographic evaluation using a calibrated AP radiographs of both clavicles. Two groups were
constituted and analysed according to a radiologic shortening ≥ two cm (patients and assessor
blinded). Sub-analyses were performed to find any relevant clinical threshold.
Results: The rate of shortening ≥ two cm in this cohort is 16.1% (10 patients). No clinical
differences between the two groups for Constant scores (shortened ≥ two cm = 96.0 ± 6.0 vs 95.2
± 6.6, p=0,73) and DASH scores (8.4 ± 11.9 vs 5.4 ± 8.1, p=0,32). A slight loss in flexion was
observed with a shortening ≥ two cm (175 degree ± 8.5 vs 179.3 ± 3.4, p=0,007). No clinical
threshold (in absolute or relative length) was associated with lower functional scores. No
relationship between clinical results and patient characteristics. Interestingly, cosmetic was not an
issue for patients.
Conclusion: This study could not demonstrate any clinical impact of the shortening of the clavicle
in patients treated conservatively for a fracture in the middle third. Functional scores are excellent
and the slight difference in flexion is not clinically significant. We were not able to find patients
unsatisfied with their treatment. The poor functional outcomes described in previous studies are
mainly related to non-unions. Just after the trauma, protraction of the scapula and single AP views
centered on the clavicle can overestimate the real shortening. An initial shortening of the clavicle ≥
two cm is not a surgical indication for fractures in the middle third. Patient selection for surgery
should focus on risk factors for non-unions.
23
CORA P09
The Economic Impact of Point of Care Shoulder Ultrasonography in Worksafe BC Patients
Tym Frank, University of British Columbia
Michelle Tan, Clayton Chmelik, William D. Regan, Danny P. Goel
Purpose: Shoulder pain in labourers is a common reason for referral to an orthopaedic specialist.
Image-guided injections are a useful adjunct to the history and physical exam for the diagnosis of
specific shoulder-related pathology. Often workers are referred for outpatient image-guided
injections performed by anaesthesiologists or radiologists. Referred image guided injections delay
treatment, increase worker days lost and is cost inefficient. Point-of-care (POC) shoulder
ultrasound by the orthopaedic surgeon is gaining interest in Canada. The purpose of our study was
to demonstrate a significant cost-savings associated with orthopaedic driven image guided
shoulder injections when compared to outsourced injections by anaesthesiologists and/or
radiologists.
Method: A retrospective chart review was performed for all Worksafe BC patients at the Visiting
Specialist Clinic (VSC) referred between 2014-2015 for image-guided diagnostic shoulder injection.
Inclusion criteria included patients referred from VSC orthopaedic surgeons for diagnostic and/or
therapeutic image guided injections. Exclusion criteria included those patients who were referred
with prior injections or those not arranged through VSC. Primary outcome measure included billing
data collected for each of these image-guided injections. Secondary outcomes included wait times
between 1) VSC consultation and image-guided injection and 2) image-guided injection and
subsequent VSC consultation. The cost associated with these wait times was also identified.
Results: A total of 136 image-guided shoulder injections were referred in 2014. The average age
of the patients was 48.7 (Range: 25-72). These injections comprised of 6 acromioclavicular; 39
glenohumeral; 39 long-head-of-biceps tendon; 42 subacromial and 10 combination. Average time
from initial VSC consultation to injection was 22 business days (median 20 days). Average time
from injection to subsequent VSC consultation was 27 business days (median 24 days). Average
fee-code payment for a single image-guided injection was between $989.92 - $1423.30. Total net
injection fee amount was $127,888.18. Total cost of injections plus worker days lost equates to a
cost of $727,638. In contrast, an orthopaedic surgeon driven POC ultrasound guided injections
results in approximately a $3,300,690.90 cost savings over 5 years.
Conclusion: Point of contact ultrasound may significantly reduce wait times associated with
referred imaged guided shoulder injections. It also may reduce the lag time between initial VSC
referral to post injection follow up and treatment. In combination, the economic impact is profound
for POC ultrasound performed by the orthopaedic surgeon in this patient population.
24
CORA P10
Implication of Mitogen-activated Protein Kinase in Naproxen Induced Type X Collagen
Expression in Human Bone Marrow Derived Mesenchymal Stem Cells
Abdulrahman Alaseem, McGill University
Padma Madiraju, Sultan Aldebeyan, John Antoniou, Fackson Mwale
Purpose: Several studies have shown that type X collagen (COL X), a marker of late stage
chondrocyte hypertrophy (associated with endochondral ossification), is expressed in
mesenchymal stem cells (MSCs) from osteoarthritic (OA) patients. In a recent study, we found that
Naproxen, but not other NSAIDs (Diclofenac, Ibuprofen and Celebrex), can significantly induce the
expression of type X collagen in MSCs isolated from bone marrows of healthy donors as well as
from OA patients. The purpose of the present study was to investigate the intracellular signaling
pathways that mediate Naproxen induced COL X expression in MSCs from normal and OA
patients.
Method: Normal human stem cells were purchased from Lonza (Switzerland). These cells were
grown in media supplemented with or without Naproxen (control). Osteoarthritis patient’s MSCs
were harvested from aspirates from the intramedullary canal of donors (60–80 years of age)
undergoing hip replacement surgery for OA, using a protocol approved by the Research Ethics
Committee of the Jewish General Hospital. Since the bone marrow is well vascularized, the
concentration of Naproxen (100 µg/ml) supplemented into the media was based on circulating
levels in the blood. Protein expression and phosphorylation were determined by immunoblotting
using specific antibodies (COL X, p38, phosphorylated-p38, JNK, phosphorylated-JNK, ERK,
phosphorylated-ERK). GAPDH was used as a loading control.
Results: We first determined basal phosphorylation levels of the three major members of mitogenactivated protein kinase family (Erk, JNK and p38) in MSCs from both normal and OA patients. The
phosphorylation of MAPKs (Erk, JNK and p38) in MSCs from OA patients was significantly higher
than in normal. Values represent the mean (%) ± standard deviation of 7 donors (p-ERK, 307.4 ±
69.31, p < 0.0002, p-JNK 943.4 ± 92.02, p < 0.0001, p-P38 124.8 ± 26.44, p < 0.0479) as
percentage to normal human MSCs (100%). Incubation of normal MSCs with Naproxen 100 ug/ml
for different periods of time had significantly increased the phosphorylation of ERK at one hour (
153.1 ± 12.42, p < 0.05 ) and reached to below control levels at 6 hours ( 50.09 ± 25.83, p < 0.05 ).
Naproxen also significantly increased the phosphorylation of JNK in first 30 minutes and reached to
control levels by 1 hour. Similarly, the phosphorylation of p38 also increased significantly at 30 min
and sustained up to 6 hours. Furthermore, we also found that Naproxen significantly stimulated the
expression of COL X in normal MSCs treated for one, two and three days.
Conclusion: Little is known about the intracellular mechanisms involved in chondrocyte
hypertrophic differentiation of OA MSCs. Targeting these pathways might help to prevent or revert
chondrocyte hypertrophic differentiation. In this study, we show that Naproxen-Induced COL X
expression in normal MSCs is probably mediated by the activation of MAPK pathway.
25
CORA P11
Outcome of Distal Biceps Tendon Repair with and without Concomitant Bicipital
Aponeurosis Repair
Catherine Conlin, University of Toronto
Amanda Pennings, Amr Elmaraghy
Purpose: The purpose of this pilot study was to examine the impact of a two-incision distal biceps
tendon (DBT) repair with and without repair of the bicipital aponeurosis (BA) on subjective and
objective outcome measures in patients with distal biceps tendon ruptures.
Method: Retrospectively collected data of patients with DBT ruptures at least one year after
surgical repair were used for the data analysis. Patients underwent either an isolated DBT repair or
a DBT repair with concomitant BA repair after a change in practice by the primary surgeon.
Results: Data of 24 male patients with a DBT rupture were used for the analysis. Of 24 patients,
13 (54%) had a DBT and BA repair (DBT + BA repair group) and 11 (46%) had an isolated DBT
repair. The DBT + BA repair group returned to recreational activities faster (77% within 6 months,
100% within one year) than the isolated DBT repair group (36% within 6 months, 91% within one
year and 100% returned after more than two years). There was a trend toward better Patient-Rated
Elbow Evaluation Pain scores (PREE-Pain) in the DBT + BA repair group (p = 0.09). A trend also
emerged toward better subjective post-operative strength as compared to pre-injury level (77% of
patients in the DBT + BA repair group reported perceived strength had returned to pre-injury level
versus 46% of patients in the isolated DBT repair group, p = 0.12). No significant differences were
found in objective strength or range of motion measurements.
Conclusion: This pilot study suggests repair of the bicipital aponeurosis in conjunction with DBT
repair may lead to better subjective outcomes after DBT rupture. Further investigation with a larger
population is required to better elucidate these potential differences.
26
CORA P12
Learning what not to do in Orthopaedic Research: A Systematic Review of Retractions for
Research Misconduct
James Ray Yan, McMaster University
Austin MacDonald, Louis-Philippe Baisi, Nathan Evaniew, Michelle Ghert
Purpose: The Royal College of Physicians and Surgeons of Canada mandates that orthopaedic
residents be provided with the opportunity to explore research opportunities during their residency.
This standard covers the CanMEDS competencies of scholar, communicator and professional.
Retractions occur in the published literature when the authors of a study or article are found to
have committed research misconduct compromising the integrity of the study. The purpose of this
study was to determine the reasons for retraction of studies in the orthopaedic literature, with the
ultimate goal of educating residents on the importance of CanMEDS competencies in the research
process.
Method: In order to systematically identify all relevant retracted papers, two reviewers
independently searched MEDLINE (1995 – present), EMBASE (1995 – present), and the Cochrane
Library (1995 – current), using MeSH keyword headings and the ‘retracted’ filter. We conducted an
additional search through an independent website that reports and archives retracted scientific
publications (retractionwatch.com). We used keyword combinations for the website search, which
was carried out up to September 9th, 2015. Two reviewers independently extracted data including
reason for retraction (plagiarism, data fabrication, data manipulation, duplication, etc), as well as
type of study, journal impact factor and country of origin.
Results: Of 1176 studies identified from the initial search, 1085 were excluded (topic unrelated to
orthopaedics or musculoskeletal science, duplicate paper, retraction information unavailable or not
available in English). An additional 19 studies were identified through RetractionWatch. In the end,
we included 110 studies for data extraction. The retracted studies were published in journals with
impact factors ranging from 0.00 (discontinued journals) to 13.26. In the 20-year search window,
only 25 papers were retracted in the first 10 years (1995-2005), with the remaining 85 papers
retracted in the most recent decade (Figure 1). Fraudulent data (27), plagiarism (25), duplicate
publication (19), and data errors (13) were the main reasons for retractions. Twenty-eight studies
were retracted for other issues such as authorship misattribution, falsified peer reviewer details, or
lack of ethics approval. The average time between article publication and retraction was 33.6
months. Retracted articles have been cited up to 157 times.
Conclusion: Our findings suggest that academic misconduct, either through plagiarism or through
fraudulent data representation, is the most common reason for retractions in orthopaedic research.
As in other scientific fields, retractions within orthopaedics have been on the rise, likely due to
increased awareness and advanced software detection. It was noted that there was not a
consistent standard applied to the notice of retraction issued by the various journals regarding full
disclosure and transparency. Additionally, several retracted studies continue to be highly visible
even after their retractions were issued. Many are readily retrievable online and the ‘retracted’ state
is not consistently watermarked. The results of this study emphasize the importance of applying
CanMEDS competencies to research education.
27
CORA P13
Up to Five Years’ Follow-up of Short Cemented Stems in Complex Primary Total Knee
Arthroplasty: A Prospective Study
Mathieu Angers-Goulet, Université Laval
Martin Bédard
Purpose: Short stems in complex primary TKA are used to reduce tibial lift-off and to resist
shearing stress1. They offer the advantages of increased fixation in comparison with a standard
keel while minimizing micromotion and potentially eliminating end-of-stem pain associated with the
use of a longer press-fit stem. However, clear indications for its use in primary complex arthroplasty
(TKA) have yet to be defined, and, to our knowledge, its performance has not been evaluated in
the literature. The main objective of this study is to evaluate the global performance of short
cemented metaphyseal stem components in a complex primary TKA population.
Method: At baseline, patient had to complete a general information questionnaire and the
American Knee Society Score (KSS), a standardized physical and standard knee and goniometry
radiographs were taken. Follow-ups occurred at three, six, and 12 months, and annually thereafter.
All complications were recorded and reviewed at the end of the study. Osteolysis evaluation was
performed on all most recent radiographs using the Knee society total knee arthroplasty
roentgenographic evaluation and score. KSS scores, clinical scores and radiological scores were
analyzed and statistical parameters were calculated. Kaplan-Meir analysis was used for survival
rate with defined end points as follow: 1) Component displacement 2) Osteolysis score > 10 3)
Infection or removal of prosthesis.
Results: This present study reports the results of up to five years of follow-up for a cohort of 91
patients who underwent complex primary total knee arthroplasty (TKA) requiring short stem fixation
between January 2009 and October 2014. There were 40 females (46 TKAs) and 40 males (45
TKAs). The left knee accounted for 52.7% of the surgeries while the right knee accounted for
47.3%. The average body-mass index (BMI) was 31.8 kg/m2. The greatest clinical improvement
was observed between baseline and three months, with pain score improving by 30.5, Knee score
improving by 37.1, and function scored improving by 16.4. At their most recent follow-up, the KSS
improved by 41,9% for knee score, by 37.4% for function score and final range of motion increased
by 10 degrees. Radiological assessment showed that all Knee Society roentgen graphic scores
were under 10, without any evidence of impending or possible failure. Only one revision was
required in this cohort for a patient suffering a deep chronic infection. At five years, the KaplanMeier survivorship analysis revealed a 100% survivorship for aseptic loosening and a 98.9%
survivorship for infection and revision of the components for any reason.
Conclusion: At midterm, the present study demonstrates that TKA with short cemented stems
results in good functional, clinical, and radiological outcomes. Strong consideration should be given
using short cemented metaphyseal stem in primary complex TKA. Further studies and long-term
follow-up will be necessary.
28
CORA P14
Head Injury in Patients with Hip Fractures: A Retrospective Review
Kajeandra Ravichandiran, University of Western Ontario
Terry-Lyne McLaughlin, James Howard, Brent Lanting, Edward Vasarhelyi
Purpose: Hip fractures are common orthopaedic injuries in the geriatric population requiring
surgical intervention to stabilize and restore function. Often these injuries are the result of falls and
the potential exists for a minor head injury in the form of an intracranial bleed at the time of hip
fracture. In the emergency literature, the CT head rule using the New Orleans Criteria or Canadian
CT head rule is often applied to determine if a patient requires a CT scan of the head. However, in
the hip fracture population, these scales are not useful since all patients would require a CT head
based on the age criteria of these scales should they be suspected of having a minor head injury.
The purpose of the current study is twofold. First to determine the frequency of CT head exams
and the incidence of head injury in patients that sustained a hip fracture. Second, to determine any
clinical implications such as delay to surgery, neurosurgical intervention or post-operative
complications in hip fracture patients who had positive CT scans of the head.
Method: A retrospective review was completed to identify all hip fractures presenting to an
academic health centre between 2007 and 2012. Medical records were reviewed to determine if
hip fracture patients received a CT scan of the head as part of their workup, indicating a suspicion
of minor head injury. Demographic data including age, gender and type of operative procedure was
recorded. Charts were reviewed on those patients who had a CT head to determine its outcome as
an intracranial bleed or normal. Those with positive CT scans were further evaluated to determine
if any changes in management were made as a result of this finding.
Results: A total of 1327 patients were reviewed. They had an average age of 81±11 years of age.
Sixty-three of the patients were under the age of 65. Hip fractures were treated with a bipolar in
63% of the hip fracture patients and with a dynamic hip screw in 37% of the patients. Twenty-two
percent of the patients received CT scan of the head. Incidence of an intracranial bleed was in 2%
of the hip fracture population or 9% of those who had their heads scanned with a CT. None of
these patients received any neurosurgical intervention for evacuation of the hematoma.
Conclusion: The data suggests that in patients with hip fractures, CT scans of the head may not
have much utility. Even in the 2% of the patients with a positive intracranial bleed, no neurosurgical
intervention was required. Further work is required prior to establishing recommendations for
performing CT scans of the head in hip fracture patients, however, the scans did not alter
management and given challenges of resource allocation, radiation exposure and costs associated
with CT scans these may be an unnecessary investigation in this patient population.
29
CORA P15
The Impact of Spinal Manipulation on Lower Extremity Motor Control in Lumbar Spinal
Stenosis Patients: A Single-blind Randomized Clinical Trial
Mina Aziz, University of Manitoba
Michael Johnson, Steven Passmore, Michael Goytan, Cheryl Glazebrook
Purpose: Spinal manipulation can offer lumbar spinal stenosis patients a degree of pain relief and
improve self-reported disability. Fitts’ law can be used to predict the task difficulty of rapid aiming
movements as a function of the distance to target (amplitude of movement) and target width.
Previous studies have shown that lumbar spinal stenosis patients differ in their lower extremity
motor control, as modeled by Fitts’ law, when compared to healthy controls. The purpose of this
study is to quantify the impact of a single spinal manipulation intervention on patients with lumbar
spinal stenosis using a Fitts’ Law lower extremity movement task. We hypothesize that patients
who receive spinal manipulation will demonstrate improved motor performance compared to a nonintervention (NI) group.
Method: A cross sectional single blind randomized design was utilized for this study. Participants
with lumbar spinal stenosis (N=14; Swiss Spinal Stenosis score of M=63.2, SD=15.9) performed
baseline testing and underwent a covariate-adaptive randomization. The treatment and the control
groups each performed a foot-pointing task to four targets with different indexes of difficulty (ID).
Participants completed 10 trials per target, per foot, resulting in 80 total trials both pre and postintervention. Pain, lumbar range of motion, and motor performance were assessed at baseline and
following lumbar spinal manipulation or NI.
Results: Significant main effects for movement time, peak velocity, time to peak velocity and peak
acceleration was observed across task difficulty as predicted by Fitts’ Law, F(1,7)=8.37; p<0.001,
F(1,7)=9.46; p<0.001, F(1,7)=5.59; p<0.001 and F(1,7)=2.74; p<0.001 respectively. Planned
comparisons of the movement time main effect revealed significant differences between the two
most difficult targets post-spinal manipulation (M=740 milliseconds, SD=230 milliseconds and
M=780 milliseconds, SD=240 milliseconds; t(6)=3.042, p=0.02). For all other comparisons, gross
movements required to attain appropriate target amplitude superseded any precision movements
associated with coordinated movement to targets of different sizes. No significant differences in
pain, or lumbar range of motion were found within or between groups.
Conclusion: Participants undergoing spinal manipulation demonstrated immediate improvement in
movement time specifically in their motor coordination in the most challenging contexts. No
immediate differences in pain or lumbar range of motion were observed. The findings of this study
will inform surgeons of potential objective treatment outcomes when considering non-operative
care for lumbar spinal stenosis patients. In the future, research on the impact of spinal
manipulation on lumbar spinal stenosis patients should quantify the impact of a course of care
(multiple spinal manipulation treatments over multiple days) which more closely reflects nonoperative clinical practice.
30
CORA P16
A New Innovative Intraoperative Test for the Detection of Syndesmosis Instability in
Supination-external Rotation (SER) Injuries
Nayla G. Papadopoulos, Université de Montréal
Yves Laflamme, Jérémie Ménard, Dominique Rouleau, Stéphane Leduc, Jonah Davies, MarieLyne Nault
Purpose: Classical intraoperative tests for detection of ankle syndesmosis instability lack
sensitivity and specificity. A new ‘freer torque test’ (FTT) allowing syndesmotic instability
assessment through direct visualization is compared to the external rotation stress test (ERST) and
lateral hook stress test (LHST) in this cadaveric study.
Method: Ten fresh frozen human lower limbs secured to a custom-built stabilizing frame were
progressively sectioned at the syndesmotic level to simulate different stages of SER injuries. Stage
one corresponds to the antero-inferior tibiofibular ligament sectioning. The addition of interosseous
membrane section corresponds to stage two. In the third stage, all three syndesmosis ligaments
are sectioned. At each stage, three stress tests (LHT, ERT and FTT) were applied to the limbs. A
digital dynamometer was used to control and reproduce consistently the applied force. The FTT is
performed by inserting a freer elevator in a small window created in the syndesmosis through the
classical lateral approach of fibular fixation. The freer tip is held against the postero-lateral aspect
of the tibia while the belly of the tool is forced against the fibula in a torque-like motion. For each
test, medial clear space and tibiofibular clear (TFCS) space are recorded on a true mortise
radiograph. Direct measurements of tibiofibular diastasis are made concurrently.
Results: FTT was easier and faster to perform than the ERST and LHST. It also required
considerably less physical strength to detect instability. At stage one injury, tibiofibular diastasis
increased by only 0.6mm (NS) compared to the intact situation for all stress tests. This
demonstrates that AiTFL rupture alone does not destabilize the syndesmosis. In stage two and
three, diastasis was statistically significant for each stress test. In stage two, tibiofibular diastasis
was 1.9mm (p=0.000) for LHST, 2.1mm (p=0.000) for ERST and 2.9mm (p=0.000) for FTT. No
significant differences could be identified using fluoroscopic views for the stage 2 stress tests.
Conclusion: This study shows that regardless of the test used intraoperatively, direct visualization
of tibiofibular diastasis is more sensitive than fluoroscopy for the diagnosis of syndesmotic
instability. The new FTT is more sensitive for the detection of syndesmosis instability than the
LHST and ERST. The FTT is especially useful in detecting incomplete syndesmosis ruptures that
need to be fixed while not grossly unstable (stage two injuries). We recommend a 3mm tibiofibular
diastasis on direct visualization as a threshold for fixation when using the FTT.
31
CORA P17
The Effect of Distal Nail Tip Position on Coronal Plane Deformity in Antegrade Nailing of
Sub-isthmic Femur Fractures
Christopher Dowding, University of Ottawa
Derek Butterwick, Steven Papp, Wade Gofton, Allen Liew
Purpose: To evaluate the relationship between the position of the tip of intra-medullary femoral
nails and the quality of fracture site reduction during fixation of sub-isthmic diaphyseal femur
fractures.
Method: This is a retrospective case series of data collected prospectively at an urban level one
trauma centre. Forty sub-isthmic diaphyseal femur fractures presenting between 2007 and 2012
were identified. Post-operative radiographs were assessed for nail tip position using two methods:
position relative to the notch and position relative to the physeal scar. These measurements were
compared to the coronal fracture site angulation in each case. The main outcome measurements
were quality of fracture site reduction and nail tip position.
Results: The average fracture site angulation was 1.5 degrees valgus. Measuring the nail tip
position in reference to the physeal scar showed a poor inter-observer reliability. When measured
in reference to the intercondylar notch, nail tip position showed a high inter-observer reliability and
averaged 6.6 mm medial. Fracture site angulation was strongly correlated to nail tip distance from
the notch and a tip position of 2.7 mm medial corresponded to neutral fracture site angulation in the
coronal plane.
Conclusion: Nail tip position influences quality of reduction during closed intra-medullary nailing of
sub-isthmic femur fractures. A tip to notch apex distance of 2.7 mm medial is most likely to result in
neutral fracture site angulation in the coronal plane.
32
CORA P18
Concussions in Community-level Rugby: Risk, Knowledge, and Attitudes
R. Kyle Martin, University of Manitoba
Travis Hrubeniuk, Christopher D. Witiw, Jeff Leiter
Purpose: Rugby union is the most played full contact team sport in the world. The high speed and
aggressive nature of the competition places participants at risk for various injuries; in particular,
concussions. Most of the clinical evidence pertaining to concussions in rugby has been generated
in traditional markets for the sport, such as Europe, Australasia, and South Africa, and has
primarily focused on elite level or youth divisions. Presently, there is a paucity of data pertaining to
concussions in adult players participating at the community-level in North America. These players
may have a different risk profile than their elite or younger counterparts, owing to experience
levels, attitudes toward the game, and vigilance on the part of league organizers to recognize and
manage injuries of this nature. In addition, players may have less timely access to medical
resources and greater concerns with respect to the effect of injuries on occupational attendance
and status, and thus may potentially represent a vulnerable cohort. We aim to estimate the risk of
sustaining a concussion during participation in Canadian community-level rugby and to summarize
the collective knowledge and attitudes toward concussions.
Method: An anonymous, voluntary survey was administered to all 464 senior level rugby players
registered in the Canadian province of Manitoba in 2015. Two primary domains were assessed: 1)
concussion history from the preceding season which included occurrence, symptomatology, and
impact on daily activities; 2) knowledge and attitudes towards concussion risks and management.
Results: In total, 284 (61.2%) rugby players responded. Concussion symptoms were reported by
106 (37.3%). Of those, 50% of were formally diagnosed with a concussion and 25% missed school
and/or work as a result. Proportionally more female players reported symptoms than male
participants (49% vs. 30%, respectively; p < 0.05). The danger of playing while symptomatic was
recognized by 93.7% of participants, yet 29% endorsed that they would continue while
symptomatic, and 49% stated they would be less likely to report symptoms during an important
match. Furthermore, 39% felt they were letting others down if they stopped playing due to a
concussion, but less than 2% of players said they would feel let down if a teammate stopped
playing.
Conclusion: Concussions are commonplace in adult community-level rugby and these injuries
have a notable impact on daily activities. Significantly more female players reported symptoms of a
concussion during a single season when compared with their male counterparts. This finding is in
keeping with emerging evidence which suggests women may be at higher risk of sustaining
concussions and may take longer to recover. Despite a near-ubiquitous appreciation for the
dangers of concussions, many players suggested they would be willing to continue to play while
experiencing symptoms. The observed discord between knowledge and attitudes suggests there
may exist an underlying culture of ‘playing injured’ in adult community-level rugby. This tendency
for players to underreport symptoms requires further investigation and may warrant the institution
of independent concussion spotters and standardized concussion protocols that mandate removal
from play.
33
CORA P19
A Novel Classification System for Distal Ulna Fractures Associated with Distal Radius
Fractures
Laura Sims, University of Saskatchewan
Geoffrey Johnston
Purpose: Distal ulna fractures (DUF) are commonly associated with distal radius fractures (DRF).
Recent evidence suggests that the presence and type DUFs is correlated with associated distal
radius fracture outcomes. There is currently no standardized and validated classification system for
characterizing distal ulna fractures associated with distal radius fractures. The purpose of this study
was to assess the utility of our newly created, inclusive classification system for distal ulna
fractures.
Method: A classification system for distal ulna fractures was devised based on fracture pattern and
location. Type 1 fractures are those in the ulnar styloid, with type 1a involving the apex and Type
1b being in the body of the styloid; Type 2 fractures are proximal to the styloid and involve the ulnar
fovea, with Type 2t adopting a transverse pattern and Type 2o an oblique pattern; Type 3 fractures
involve the ulnar head; and Type 4 fractures were those proximal to the head, with Type 4n being
through the neck (including the physeal scar) and Type 4s involving the distal shaft. A
questionnaire was distributed to all members of the Canadian Orthopaedic Association in both
French and English, asking participants to evaluate 29 radiographic images of distal ulna fractures.
Only one answer was deemed to be correct for all but one radiograph, while for one radiograph
there were two fracture types to be identified.
Results: There were 144 respondents to the questionnaire. The mean overall score was 83.39%
and ranged from 62.07% to 100%. In 21 out of 29 images, greater than 80% of raters agreed on
the correct classification. For Type 1a fractures 91.42% answered correctly. For Type 1b fractures
81.81% were answered correctly. For Type 2t fracture 75.98% were answered correctly. For Type
2o fractures 97.56% were answered correctly. For Type 4n fractures 78.57% answered correctly,
and for Type 4s fractures 84.83% answered correctly. Individual questions where fewer than 80%
answered correctly were analyzed, revealing that a common wrong answer was most often
selected. For type 1b fractures, 82.50% of wrong answers selected were type 1a. For type 2t
fractures, 98.27% of wrong answers were type 1b; for type 4n 89.65% of wrong answers selected
were type 2o; and for type 4s fractures, 98.70% of wrong answers were type 4n. A type 3 fracture
occurred in combination with a type 2t fracture and was correctly identified by only 34.35%. The
correct combination was correctly identified by only 19.13%.
Conclusion: The Canadian orthopaedic community has demonstrated that they can readily
reproduce this new classification system, previously correlated with radiographic outcomes for the
associated distal radius fractures. This new classification is an inclusive and simple way of
characterizing these fractures with an overall agreement greater than 80%. The results will guide
the authors to further distinguish between the definitions of Types 1b and 1a, 1b and 2t, and 4n
and 4s as well as Type 3 fractures. This provides treating physicians with a uniform way of
describing these fractures, useful both in predicting outcomes and conducting future research.
34
CORA P20
Post-operative Analgesia with the Hamstring Donor Site Local Block in Anterior Cruciate
Ligament Reconstruction
Maxime Beaumont-Courteau, McGill University
Antony Liddell, Paul Martineau, Mark Burman
Purpose: Proponents of anterior cruciate ligament reconstruction with hamstring autograft often
cite decreased donor-site morbidity as one of the major advantages of this technique over other
reconstruction options. Patients do, however, frequently complain of donor-site pain in the shortterm post-operative period. A common post-operative regime includes femoral nerve
catheterization and anaesthetic infiltration over 48 hours.
This prospective double-blinded randomized controlled trial aims at showing that the addition of
local anaesthetic at the hamstring donor site would decrease the short-term post-operative pain in
patients compared with those receiving a femoral nerve block only.
Method: Prior to their standard reconstructive surgery, 46 patients were recruited and randomized.
22 of them received routine analgesia; namely pre-operative femoral nerve catheterization and
infusion for 48 hours, and a spinal anaesthetic. The other 24 patients received the aforementioned
analgesia as well as the introduction of local anaesthetic to the hamstring donor site, through an
injection guided by palpating the tendon-harvesting tool. Their post-operative pain was assessed
using visual analog scale (VAS) scores and a perioperative pain diary in the immediate postoperative period and over the following 14 days.
Results: No difference between the two groups was demonstrated in the VAS scores at any time
point throughout the first two post-operative weeks. Furthermore, this was confirmed by the
narcotic analgesic usage, which also showed no difference during the same period. No difference
in early post-operative complication rate was detected between the groups.
Conclusion: This randomized controlled trial demonstrates that, in patients undergoing an anterior
cruciate ligament reconstruction under spinal anaesthesia and femoral nerve block, the addition of
a local anaesthetic block at the hamstring donor site does not decrease post-operative pain and
does not decrease narcotic analgesic usage.
35
CORA P21
Reliability in Interpreting Distal Radial Fracture Radiographs Before and After a Technique
Teaching Tutorial
Shandy Fox, University of Saskatchewan
Geoffrey H.F. Johnston, Samuel A. Stewart
Purpose: Orthopaedic surgeons use radiographic criteria for decision-making when managing
distal radial fractures in adults. Although the criteria based on anatomical deformity requires
precise measurements, no single technique has been defined. The purpose of this study was to
evaluate the intra-rater and inter-relater reliability of physicians’ measurements of radial inclination
(RI), ulnar variance (UV) and radial tilt (RT) in distal radius fractures, before and after a tutorial on a
single measurement technique.
Method: Twelve physicians (six orthopaedic surgical residents, four orthopaedic surgeons and two
musculoskeletal radiologists) independently measured RI, UV and RT in 30 radiographs of distal
radial fractures in women 50 years and older at least one week apart on three occasions. The
senior author then instructed each participant on a single technique of measurement for these
values and the process was repeated. The impact of the tutorial was assessed using Intra-class
Correlation Coefficients (ICCs) for inter-rater and intra-rater reliability before and after the tutorial.
The intra-rater variation of the senior author was defined.
Results: Initially the ICCs did not trend upwards, suggesting that repetition itself did not promote
improvement. The ICCs promptly improved after the tutorial and this was sustained in subsequent
readings. Using the senior author’s values as a gold standard, all six readings were classified as
“accurate” if they were within 20 for RI, 1 mm for UV, and 40 for RT. Multivariate logistic regression
showed the odds of an accurate measurement was 1.6 times higher for RI after the tutorial, 3.9
times higher for UV, and 1.2 times higher for RT. The RI and UV results were statistically
significant, while RT failed to achieve statistical significance. Despite near perfect ICC values and
improved accuracy following the tutorial, substantial variability remained in select cases. This
variability among raters often placed individual patients with “borderline” measurements partly in
the operative arm and partly in the non-operative arm, highlighting limitations of the guidelines.
Further analysis of these individual patients provided insight into the most difficult and challenging
radiographic features.
Conclusion: Adoption of a standardized technique for measuring RI, UV and RT substantially
improves accuracy and inter-rater and intra-rater reliability in distal radial fractures. Despite this, we
must continue to interpret radiographic criteria with caution.
36
CORA P22
Epidemiology of Developmental Hip Dysplasia in Saskatchewan
Susan Nelson, University of Saskatchewan
Katie Rooks, Ann Dzus, Lauren Allen
Purpose: Developmental dysplasia of the hip (DDH) refers to a spectrum of anatomical
abnormalities. Despite various screening programs, delayed diagnosis still occurs. Delayed cases
are more difficult to treat and can have poorer outcomes. Rural address, low socioeconomic status,
and ethnicity have recently been associated with late presentation. The objectives of this study
were to examine the incidence of DDH, as well as factors associated with delayed presentation in
Saskatchewan.
Method: Retrospective review of paediatric orthopaedic records from the tertiary referral centre in
Saskatchewan was completed from 2008-2014. Variables collected included age at presentation,
sex, birth order, birth presentation, birth complications, laterality, family history of DDH, postal code
and treatment. Socioeconomic and geographic indicators were determined from postal code using
the 2011 National Household Survey. Population level variables included income, ethnic origin,
distance from referral centre and education. Associations were examined with bivariate and
multivariate analysis.
Results: There were 108 new presentations of DDH; 34 cases presented after age three months.
Demographic data showed 83.3% of cases were female, 48.1% involved the left hip, 17.2% had a
positive family history, 57.1% were first born, and 27.9% were breech. An estimated 5.6% of
patients were Aboriginal. The mean age at presentation was 199.7 days.48% of cases lived in the
same city as the referral centre. Late presenting cases lived on average 46.19 km farther from the
referral centre and had a lower mean population, percent of adults with post-secondary education
and income, however, none of these were statistically significant. No significant associations were
found within the demographic data.
Conclusion: Overall incidence of DDH was not estimated due to few cases from southern areas of
the province presenting to the tertiary referral centre. The estimated incidence of DDH in the
Aboriginal population from our sample was lower than previously reported in the literature. This
association may be related to earlier swaddling practices, rather than Aboriginal ethnicity. There
was a trend toward lower socioeconomic indicators and an increased distance from the referral
centre in cases of late presentation, in keeping with recent literature exploring these factors. This
suggests there may be deficits in the current selective screening protocols in North America. The
study is limited by the retrospective nature of the research and the population level data obtained
for certain variables. Future research to collect prospective individual level data may help elucidate
important associations. Also, identifying any additional cases would increase the power to detect
significant associations with late presentation, and allow an accurate estimate of overall incidence.
37
CORA P23
Trochanteric Fixation using a Third Generation Cable Device - Ottawa’s Experience
Andrew Stewart, University of Ottawa
Hesham Abdelbary, Paul Beaulé
Purpose: Trochanteric non-union/insufficiency fracture is a common arthroplasty complication,
resulting from transtrochanteric approaches to the hip, periprosthetic hip fractures and more
recently, osteolysis related bone resorption. With the growing hip arthroplasty population, the
incidence of trochanteric fracture is expected to be an ongoing problem. Cable-plate devices
combining circlage cable with trochanteric plates were introduced over 40 years ago to provide a
rigid construct that would oppose the massive forces transmitted through the greater trochanter
and provide a stable environment for healing.
Third generation cable-plate devices were recently introduced with advancements in biomechanical
design. Despite a paucity of evidence for their use, they have been the primary implant for
trochanteric fixation at our institute. Only one clinical trial has thus far been performed assessing
their use, which revealed a reoperation rate of 4.3% and a union rate of 95.7%.
Objective: The objective of this study is to investigate the rates of reoperation and trochanteric
non-union after using the Accord Cable-Plate system at our institution over the past six years.
Method: We retrospectively reviewed 52 consecutive applications of the Accord Cable-Plate
system for greater trochanteric fixation from February 2008 to March 2014 with the following
indications: periprosthetic fracture (n=26), complex primary arthroplasty (n=8), complex revision
arthroplasty (n=18). Radiographic analysis of bony apposition and union was performed as
previously described by Hamadouche et al. Primary outcomes included rates of reoperation and
radiographic union. There were 32 patients with over six months of follow up (death n=9, unable to
return for radiographs n=7, unable to contact n=4). Exclusion criteria for reoperation rate included
loss of contact before six months (n=4). Exclusion criteria for union rate included less than six
months of radiographic follow-up (n=20).
Results: Reoperations in which the Accord system was removed was performed for 15 patients
(31.3%) at a mean of 8.1 months (range 0.5-39.0 months) post insertion. Indication for implant
removal included: lateral hip pain (5/15), infection (5/15), periprosthetic fracture (1/15), trochanter
fragment escape (1/15), and removal of hardware during revision for other reasons (3/15).
Radiographic assessment at minimum six months showed bony union in 19/32 and fibrous union in
3/32 applications of the cable-plate system.
Conclusion: Despite similar indications for Accord cable-plate implant use, we observed
significantly higher reoperation rates (31.3%) and lower trochanteric union rates (68.8%) than
previously described in the literature.
38
CORA P24
Correlating Pain Patterns in Adolescent Idiopathic Scoliosis Patients using EOS 3D
Morphological Analysis
Fan Jiang, McGill University
Leonardo Simoes, Jean Ouellet, Jenny Sun, Neil Saran, Sheila Bote, Catherine Ferland
Purpose: Adolescent Idiopathic Scoliosis (AIS) is commonly thought to be a painless lordoscoliotic deformity of the spine. However, some studies have shown that 25 to 50% of the patients
with AIS present with pain. Traditionally, the three dimensional scoliotic deformity seen in patients
with AIS has been assessed and classified using the Cobb angle and Lenke Classification
respectively. With the arrival of new low dose radiation EOS technology, we are now able to
quantify global and intersegmental changes in AIS spines using three dimensional reconstruction.
Hypothesis: EOS 3D imaging analysis allows better correlation of morphological changes in the
spine of AIS patients with symptoms of pain.
Method: A total of 59 patients with the diagnosis of AIS (7 male and 52 female, mean age of 14.3
years old) who were scheduled for elective posterior spinal fusion were enrolled in the study. Preoperatively, pain data was collected using the numerical visual analogue (VAS) pain score and the
SRS-22 score. Pre-operative posterior-anterior and lateral imaging of the spine were performed
and reconstructed into 3D models using the EOS software. Global and segmental intervertebral
orientation was generated, identifying the maximal deformity orientation and correlated with
patient’s clinical presentation. In addition, standard scoliosis curve assessment using Cobb’s angle
and Lenke classification as well as pelvic parameters were also analyzed and correlated with
patients’ pain. Statistical analysis was performed with GraphPad Prism 6.
Results: Lenke classification and classic curve parameters did not correlate with pain, with the
exception of hyper-lumbar lordosis (>60 degrees) (r=0.32, p=0.06). Hyperlordotic patients reported
greater intensity of pain than normal lordotic patients (U=81.50, p=0.04). Investigation of 3D
parameters from global and intersegmental vertebral orientation showed that with the exception of
high intervertebral frontal and lateral tilt of L4 over L5, no other 3D parameters correlated with pain
patterns in patients with AIS.
Conclusion: With the additional 3D morphological analysis generated by EOS technology, we
were not able to identify any anatomical characteristics associated with pain in patients with AIS
with the exception of hyperlumbar lordosis.
39
CORA P25
Lower Stimulation Thresholds at the Apical Pedicle in Paediatric Spine Deformity
Katie Rooks, University of Saskatchewan
Jonathan Norton, Anne Dzus, Lauren Allen, Heather Hansen, Douglas Hedden
Purpose: The evolution of operative technology has allowed correction of complex spinal
deformities. Neurological deficits following spinal instrumentation is a devastating complication and
the risk is especially high in those with complex sagittal and coronal plane deformities. Prior to
intraoperative evoked potential monitoring, spinal cord function was tested using the Stagnara
Wake up test, typically performed after instrumentation once the desired correction has been
achieved. This test is limited as it does not reflect the timeframe in which the problem occurred and
it can be dangerous to the patient. Intraoperative neuromonitoring allows timely feedback of the
effect of instrumentation and curve correction on the spinal cord. Pedicle screws that are
malpositioned can result in poor fixation or neuronal injury. Evoked EMG monitoring can aid in
accurate placement. A positive EMG response can alert the surgeon to a potential pedicle breach
and allow them to reassess the placement of their hardware intraoperatively. The stimulation
threshold is affected by the amount of surrounding bone acting as an insulator to electrical
conduction and is variable in different regions of the spine. In the non-deformed, lumbar spine
stimulation thresholds have been established. Such guidelines have not been well-developed for
the thoracic spine, or for severely scoliotic spines. Thus our primary objective was to compare the
stimulation threshold of the apical pedicle on the concave side to the stimulation threshold of the
pedicles at the upper and lower instrumented levels.
Method: Intraoperative EMG stimulation thresholds were done at 192 apical pedicles on the
concave side of the deformity and then compared to those thresholds found at 169 terminal level
pedicles. Only pedicles for which a stimulation threshold was found were reported and excluded
those where a breach was suspected. The lowest stimulation required for an EMG response was
documented to a maximum stimulation of 20 mA.
Results:
Apex
Threshold (mean ± s.d) 16.62±0.
/mA
78
Number of Pedicles
192
Terminal
level
18.25±0.67
p<0.05 t-test
169
Conclusion: In this study we report only the thresholds for the concave side, the pedicle that is
most likely to be reduced in size. The threshold for stimulation is reduced compared to those seen
at the highest and lowest instrumented level. Most of the apexes are located in the mid-thoracic
spine with the highest instrumented levels being in the high thoracic spine and the lowest levels
being in the lumbar spine. This study provides preliminary evidence that the apical, concave
pedicle has a lower threshold than the end pedicles and one cannot rely on established thresholds
from different areas of the spine. The surgeon should be cognizant of these differences when
instrumenting at the apical level.
40
CORA P26
Iatrogenic Radial Nerve Palsy in Minimally Invasive Plate Ostheosynthesis (MIPO) of
Midshaft Humeral Fractures: A Systematic Review
Pierre Philippe Zaharia, University of Calgary
Jarret Woodmass, Nicholas Romatowski, Ryan Martin, Richard Buckley
Purpose: The preferred method for humeral shaft fracture fixation has traditionally been operative
plate osteosynthesis or intramedullary nailing. Over the past decade, reports of minimally invasive
plate osteosynthesis (MIPO) have emerged in the literature as a novel method of fixation for
humeral shaft fractures. Iatrogenic radial nerve palsy is the primary concern with this technique
given the lack of exposure and protection of the nerve during the procedure. This systematic
review aims to assess primarily the rate of iatrogenic radial nerve palsy and secondarily the rate of
infections, non-unions and hardware failure following these procedures.
Method: Two independent reviewers completed a search of Medline, Embase and Pubmed from
1946 to January 2015. The terms ”humerus (MeSH)” or “humer*” AND “fractures, bone (MeSH)” or
“fractur*” AND “minimal*” or “invasiv*” or “percutaneous*” were used in combinations to conduct the
search. Pooled estimates and 95% confidence intervals were calculated assuming a randomeffects model. Statistical heterogeneity was quantified using the I 2 statistic.
Results: A total of 2876 abstracts met the search criteria. After removal of duplicates and
assessment of inclusion/exclusion criteria, 16 articles were selected for data extraction. A total of
476 fractures in 474 patients were reviewed. The rate of iatrogenic radial nerve palsy was 2.8%
and the rate of infection was 1.7%. The rate of non-union obtained was 3.4% and the rate of
hardware failure was 1.9%.
Conclusion: Minimally invasive plate osteosynthesis technique for the fixation of midshaft humeral
fractures is both safe and effective. The overall rates of iatrogenic radial nerve palsy and infection
are lower than those previously reported for open plating techniques. Low rates of non-union and
hardware failure were obtained as well, comparable to those reported for open plating.
41
CORA P27
Efficacy of Home versus Outpatient Rehabilitation in Arthroscopic Shoulder and Knee
Procedures: A Systematic Review
Tan Chen, University of Toronto
Julia Chiovitti, Massimo Petrera, Tim Dwyer, Darrell Ogilvie-Harris, Jaskarndip Chahal
Purpose: In the current Canadian healthcare ecosystem, governments, third party payers, and
patients are trying to achieve optimal outcomes while minimizing costs. One strategy that has been
proposed to control costs is to encourage the use of home-based physical therapy in the postoperative setting. This study is a systematic review of the efficacy of home-based physical therapy
programs in comparison to the current standard of clinic-based rehabilitation programs following
arthroscopic knee and shoulder surgery.
Method: Medline, Embase, Cochrane, and CINAHL were searched for studies published up
through June 2015. The eligibility of each report was assessed based on the predefined inclusion
criteria (level one randomized studies, post-operative patients, arthroscopic shoulder or knee
surgery, one intervention containing a home physical therapy component). Minimum follow up
length was set at six weeks. Non-randomized studies and case reports were excluded from the
review. A qualitative review of the studies was conducted independently by two authors analyzing
differences between intervention groups with regard to joint and disease specific functional
outcome scores, range of motion (ROM), strength testing results, and quality of life questionnaires.
Results: Of the 861 abstracts reviewed, 14 studies met the inclusion criteria, of which nine Level I
studies were deemed to have the appropriate interventions. Publication dates ranged from 1997 to
2015. In seven of the studies, home therapy consisted of peri-operative education (classes,
pamphlets, and videotapes), unsupervised home exercise, and follow-up at pre-defined times for
evaluation and further instructions. In the other two studies, the home therapy with unsupervised
exercises began following a four to eight week post-operative course of the standard rehabilitation
regimen. Four of the studies investigated rehabilitation following arthroscopic shoulder surgery
(one Stabilization, three Rotator Cuff Repairs), and five investigated rehabilitation following
arthroscopic knee surgery (one Meniscectomy, four ACL reconstructions). A total of 282 shoulder
and 442 knee patients were investigated. Shoulder patients had follow up between 12 and 24
months, and knee patients between six weeks and 52 months. Outcome measures of the shoulder
included ROM, muscle strength, SPADI, Penn Shoulder Scale, ASES, and SF36. Outcome
measures of the knee included ROM, muscle strength, Lysholm Rating Scale, hop tests, SF36, and
quality of life questionnaires. No significant differences were identified between home and clinic
based therapy groups in patients treated with arthroscopic knee or shoulder surgery.
Conclusion: A review of Level I randomized trials demonstrated the efficacy of home physical
therapy is comparable to standard outpatient programs in the setting of post-operative arthroscopic
knee and shoulder surgery. These results could have direct implications related to future resource
utilization and expenditures in the peri-operative setting following such procedures.
42
CORA P28
Characterization and Temporal Evaluation of the Effects of Subacromial Injections for the
Treatment of Rotator Cuff Tendinopathy
Samuel Larrivée, University of Manitoba
Marie-Philippe Turgeon, Guillaume Léonard, Frédéric Balg, Patrick Boissy
Purpose: Rotator cuff tendinopathy (RCT) is a common complaint in orthopaedics. Subacromial
corticosteroid injections (CSI) are part of the standard treatment. Clinical evaluation of this
response is however imprecise, based mostly on the patient’s self-evaluation, which is poorly
correlated to the injection’s impact on shoulder function. We assessed whether accelerometry
could be a valid representation of upper extremity daily usage and could be used as an outcome
measure tool in the study of CSI effects for RCT.
Method: Twenty four subjects aged between 18 and 65 years old suffering from RCT were
recruited at the Sherbrooke University Hospital Centre outpatient orthopeadic clinic. Upper limb
function was measured one week prior to the CSI, the day of the intervention and at the two and
four weeks endpoints using self-administered questionnaires and physical measures. Self-reported
activity and pain during each day was logged by the participants using visual analog scales (VAS).
Upper limb daily use was determined using an accelerometer worn daily at the wrist and reported
as active time (AT), activity counts (AC) and number of low intensity activities (LIA), medium
intensity activities (MIA) and high intensity activities (HIA).
Results: Preliminary results show moderate to good correlation at T0 between AC variables and
VASactivity (r=0.692), self-reported questionnaires (r=0.626-0.731) and rotator cuff muscular strength
maneuvers (r=0.710-0.838) at one-week endpoint prior to CSI. Improvement was noted on the twoweek and four-week endpoints for self-reported questionnaires (all p-values < 0.02), VASpain
(p<0.001), VASactivity (all p-values < 0.05). No significant change was observed in any of the
actimetry variables, but good sensitivity to change of the AC (effect size =0.433; standardized
response mean =0.638) was observed at the two-week endpoint.
Conclusion: Wrist actimetry could be a valid representation of upper extremity use and shoulder
function, and responsiveness is promising two weeks after a CSI. Further study could help better
define surgical indications for acromioplasty on RCT patients.
43
CORA P29
Evaluating the Utility of the Lateral Elbow Radiograph in Articular Olecranon Reduction: An
Anatomic and Radiographic Study
Jeremy Kubik, University of Calgary
Prism Schneider, Ryan Martin
Purpose: Surgical reductions of intra-articular olecranon fractures are judged primarily on the
lateral elbow radiograph, as orthogonal articular imaging is not obtainable. However, there exists
no data on the adequacy of the lateral projection at identifying incongruities of the olecranon joint
surface. Since the olecranon is made up of two trochlear facets sloped approximately 45 degrees
to each other, the radiographic tangent seen on the lateral image presumably represents a small
portion of the olecranon joint surface. As such, we hypothesized that surgeons would infrequently
recognize small pre-positioned intra-articular malreductions on the lateral radiograph of cadaveric
elbows.
Method: Small intra-articular olecranon malreductions were created in six cadaveric elbows using
a ruler and a standard bone saw. Perfect lateral elbow radiographs were taken of each
malreduction. These images were randomized along with x-rays of normal cadaveric olecranons,
and the image series was presented to blinded surgeons to determine if the olecranon was
anatomic or malreduced.
Results: Fellowship-trained observers correctly identified articular olecranon malreductions on the
lateral elbow radiograph only 56% of the time. Using the Cohen's Kappa statistic, the inter-rater
reliability was found to be K = 0.69 (p < 0.001), 95% CI (0.51, 0.87).
Conclusion: Small intra-articular olecranon malreductions are inconsistently recognized on the
lateral elbow radiograph. As such, articular displacement may still be present after surgical fixation
despite obtaining true lateral radiographs intraoperatively. Accessory radiographic views of the
articular olecranon that account for the articular trochlear slopes may be indicated to improved
detection of these incongruities.
44
CORA P30
Hip Arthroscopy in Trauma: A Systematic Review of Indications, Efficacy and Complications
Gavinn Niroopan, McMaster University
Darren de SA, Austin MacDonald, Sarah Burrow, Christopher M. Larson, Olufemi Ayeni
Purpose: Treatment of traumatic hip pathology has historically required extensile exposure and
occasional surgical hip dislocation. However, this carries with it substantial morbidity, including risk
of avascular necrosis, heterotopic ossification and nerve injury. Hip arthroscopy indications have
continued to grow, with expanding utilization in the setting of trauma. This systematic review
explores the indications, efficacy and complications of hip arthroscopy in the setting of trauma.
Method: Databases (Pubmed, MEDLINE, EMBASE, Web of Science) were searched from
inception to March 2015 for studies employing hip arthroscopy in trauma treatment. Systematic
screening of eligible studies was undertaken in duplicate. Inclusion criteria included studies
pertaining to arthroscopic intervention of all traumatic hip injuries. Abstracted data was organized in
table format and descriptive statistics presented.
Results: From an initial search yield of 2809 studies, 32 studies (25 case reports, seven case
series) satisfied criteria for inclusion. A total of 145 (age range, 10 - 53) patients underwent hip
arthroscopy for six indications associated with trauma - eight for bullet extraction, six for femoral
head fixation, 82 for loose body removal, six for acetabular fracture fixation, 20 for labral treatment,
and 23 for debridement of ligamentum teres avulsion. Follow up was 2.9 years (range, eight days
to 16 years). Successful surgery was accomplished in 96% of patients, with five failures for
retained loose bodies and one for irretrievable bullet fragments. Rate of major complication - fatal
pulmonary embolism and abdominal compartment syndrome - was 1.4% (2/145), 1.4% (2/145) for
avascular necrosis, 0.7% (1/145) for nerve palsy and 0% for heterotopic ossification.
Conclusion: Hip arthroscopy appears effective and safe in the setting of trauma. This data should
be interpreted with caution due to very low quality evidence of included studies. Hip arthroscopists
must remain vigilant for abdominal compartment syndrome.
45
CORA P31
Lead Arthropathy of the Ankle Secondary to Gunshot Wound
Zahra Ramji, Université Laval
Mélissa Laflamme
Purpose: Intra-articular bullet wounds have been found to cause both local and systemic
consequences, particularly when retained over many years. There are only a handful of such cases
described in the literature, each with different implications depending on the joint involved and
whether or not the patient experienced lead toxicity.
Method: We report the rare case of a 63-year-old man with lead arthropathy of the ankle
secondary to a gunshot wound 49 years earlier. In addition to his severe tibio-talar arthritis, he
presented with significantly elevated blood-lead levels. Although he remained asymptomatic of lead
toxicity, the patient was treated with pre-operative chelator therapy and arthroscopic debridement,
excision of accessible bullet fragments and partial synovectomy.
Results: The patient was treated according to the congruent opinions of various medical
specialists. Furthermore, his overall treatment was comparable to the standard approach
recommended throughout recent literature pertaining to similar cases. However he continued to
experience ankle pain and his blood-lead levels remained elevated. He will thus undergo ankle
arthrodesis with pre-operative chelator therapy to prevent an increase in blood-lead levels
secondary to manipulation.
Conclusion: While lead arthropathy and toxicity secondary to retained intra-articular bullets has
been documented in various joints over the past decades, this is the first case of an affected ankle
reported in the English literature in 40 years. The standard of care has evolved since then,
particularly in regards to chelator therapy and the necessity for removal of intra-articular lead
fragments to prevent further lead toxicity. This case serves as an example of lead arthropathy of
the ankle and highlights the importance of balancing the standard of care with symptomatic care in
order to optimize patient well-being.
46
CORA P32
Arthroscopic Anatomic Glenoid Reconstruction: Analysis of the Learning Curve
Iustin Moga, Dalhousie University
Ivan Wong
Purpose: Anatomic Glenoid Reconstruction was first described in 2009 as a treatment for
recurrent anterior shoulder instability. This procedure involves the use of distal tibial bone graft to
recreate anterior glenoid bone surface with the goal of preventing further dislocations. Recently, an
arthroscopic approach has been proposed for this procedure, which uses the same technique as
the Bankart repair. This approach requires one additional portal, established using an inside-out
technique; it avoids damage to the subscapularis tendon, and preserves the capsule and labrum.
By comparison, the Arthroscopic Latarjet technique, the current gold standard for arthroscopic
bone reconstruction, requires four additional portals and requires splitting of the subscapularis
tendon, as well as excision of the capsule and labrum. Arthroscopic Anatomic Glenoid
Reconstruction is being proposed as an alternative to Arthroscopic Latarjet in the treatment of
recurrent shoulder instability, and this study seeks to (1) identify a learning curve for this
procedure, and (2) compare this to the learning curve for Arthroscopic Latarjet.
Method: Fifty-seven cases of surgically treated recurrent anterior shoulder instability were
reviewed. All operations were carried out with the patient in a lateral decubitus position. Twentynine patients were managed with the Arthroscopic Latarjet procedure using coracoid bone graft,
and 28 were treated with Arthroscopic Anatomic Glenoid Reconstruction using distal tibial bone
graft. Procedure start and stop times were recorded and procedure durations calculated.
Results: In the case of Arthroscopic Latarjet, the first 14 cases took an average 184 minutes to
perform, with the remaining cases in the cohort averaging 116 minutes each in duration. For
Arthroscopic Anatomical Glenoid Reconstruction, the first 14 cases took an average of 90 minutes,
with the remaining cases averaging 84 minutes each.
Conclusion: These results suggest that Arthroscopic Anatomic Glenoid Reconstruction is faster to
perform compared to the current standard of care. Further investigations into the safety and
efficacy of this procedure will help determine whether it is a better choice for surgeons looking to
learn the skill of bony augmentation for recurrent anterior instability.
47
CORA P33
Assessment of Physical Activity in Adults Undergoing Primary Anterior Cruciate Ligament
Reconstruction – A Prospective Cohort Pilot Study
Erin Gordey, University of Toronto
Tim Dwyer, Lucas Murnaghan, John Theodoropoulos. Darrell Ogilvie-Harris. Jaskarndip Chahal
Purpose: Wearable activity-measurement devices are increasingly popular in the general public
but have not been studied in patients undergoing sports medicine procedures. The purpose of this
study is to use a medical grade accelerometer to measure physical activity in patients undergoing
anterior cruciate ligament reconstruction. Specifically, we aim to determine construct validity by
comparing accelerometer-measured data to traditional patient-reported measures and to determine
the trajectory of physical activity from baseline (ACL-injured) to return to sport. To the best of our
knowledge, this is the first study using a wearable device to study activity levels in the ACL injured
population.
Method: Thirty adult patients undergoing primary ACL reconstruction with bone-patellar tendonbone or hamstring autograft were enrolled in this prospective cohort study. The Tegner scale, Marx
activity scale, International Physical Activity Questionnaire Short Form (IPAQ-SF), Knee Injury and
Osteoarthritis Outcome Score (KOOS), and EuroQol 5D were administered pre-operatively and at
three, six, and 12 months post-operatively. At these intervals, each participant was asked to wear
an Actigraph GT1M accelerometer for seven consecutive days. Time spent in moderate-tovigorous physical activity (MVPA), metabolic equivalents of physical activity (MET-minutes per
week), and average daily steps were calculated from the accelerometer output and correlated with
questionnaire scores.
Results: Thirteen patients (mean age 30 years, range 16-52; 46% female) were included in the
preliminary baseline analysis. At the pre-operative assessment (a mean of four weeks prior to
operative date and 49 weeks post-injury), patient reported outcomes were significantly lower than
those of the general population (p-values<0.01 for Tegner, IPAQ-SF, EuroQol, and KOOS). Preoperatively, 77% of patients met or exceeded the 150 minutes of MVPA per week recommended
by the Canadian Society for Exercise Physiology (CSEP), compared to 17% of the age-matched
general population. However, none of the ACL-injured patients met the 10,000 steps per day
recommendation, compared to 36% of age-matched Canadians. The Tegner score had a moderate
correlation to accelerometer-measured daily steps (r=0.39) and the Marx activity score had a
moderate correlation with accelerometer-measured MVPA (r=0.33). The IPAQ-SF, EuroQol, and
subscales of KOOS had either weak or negative correlations with accelerometer activity measures
(r<0.3). Complete baseline data will be available for 30 patients in the next three months.
Conclusion: ACL injury has a measurable impact on patients quality of life and physical activity.
Based on this small baseline data set, the Tegner and Marx activity scales are most consistent with
accelerometer-measured activity, although this correlation is moderate at best. Expansion of the
current data set and collection of post-operative values will create a trajectory of physical activity
during recovery after ACL reconstruction.
48
CORA P34
The Scholarly Influence of Orthopaedic Research: Conventional and Alternative Metrics
Nathan Evaniew, McMaster University
Anthony F. Adili, Michelle Ghert, Moin Khan, Kim Madden, Christopher Smith, Mohit Bhandari
Purpose: Researchers are experiencing an innovative shift towards online distribution of their
work. Metrics of scholarly influence that include online activity in addition to conventional citations
are gaining importance. Our objectives were to determine which types of online activity are most
prevalent in orthopaedics, identify associated factors, and develop a combined score of overall
influence.
Method: We performed a cross-sectional study of randomized controlled trials. We identified online
activity in social media, mainstream media, blogs, forums, and other sources using a commercial
provider for medical journals. We tested associations using negative binomial regression.
Results: We identified 1697 trials published between 2011 and 2014, which had a total of 12,995
conventional citations and 15,068 online mentions. The median number of online mentions to each
trial was 2 (IQR 0 to 5). Twitter (82%) and Facebook (13%) were most prevalent. Counts of online
mentions correlated with conventional citations (r=0.11, p<0.01), but accumulated more rapidly.
Higher counts of online mentions were consistently associated with longer time since publication,
higher journal impact factor, higher authors’ h-index values, and lower risk of bias (p<0.01 for
each). We found best model fit by weighting citations and online mentions equally.
Conclusion: Online activity in orthopaedics is dominated by activity on Twitter and Facebook, and
is associated with increasing time since publication, journal impact factor, authors’ h-indices, and
lower risk of bias. Our data suggest that institutions, publishers, funding agencies, and clinicians
should measure scholarly influence with a combined score that weighs online mentions and
conventional citations, equally.
49
CORA P35
A Qualitative Study of the Barriers to Rehabilitation Adherence Following ACL
Reconstruction in an Adolescent Population
Norah-Faye Matthies, University of Toronto
Adam Brown, Vehniah Tjong, Carol-Anne Moulton, M. Lucas Murnaghan
Purpose: The rate of anterior cruciate ligament (ACL) tears in adolescent patients has doubled in
the last 15 years secondary to increased participation in competitive sport. Literature has
suggested a greater emphasis on surgical intervention of unstable ACL injuries in this population,
therefore necessitating post-operative rehabilitation. Adherence to post-operative physiotherapy
has been associated with improved functional recovery and return to sport. The ability to adhere to
a rehabilitation protocol is imperative; without it, patients may struggle to return to athletic activities
in a timely manner. Post-operative rehabilitation adherence has been studied in adult populations
but not in adolescent populations. Our objective is to determine the barriers to physiotherapy
adherence in an adolescent population post-ACL reconstruction (ACLR). Our hypothesis is that
pre-injury level of exercise, self-efficacy, anxiety or depression, cost, and social support will be the
overarching themes. As these issues are not easily captured by quantitative methodology, a
qualitative design is utilized.
Method: Patients aged 14-21 who had undergone primary ACLR in the last 7 months were
recruited, along with their parents, to participate in a questionnaire and semi-structured interview.
All patients presented with primary ACL rupture and were previously free of major injury. Sport,
competition level, and associated rehabilitation costs were identified. Qualitative analysis was
performed to derive themes.
Results: Pre-injury, all patients were active in high-level sport involving cutting or pivoting
movements. Interviews revealed overarching themes that affected patient adherence. Barriers to
adherence included: difficulty finding an experienced therapist, lack of understanding home
exercises, and cost. Improved adherence was associated with: strong desire to return to sport,
innate self-efficacy, social support, and confidence in the physiotherapist.
Conclusion: Patients identified rapport with an experienced physiotherapist as fundamentally
important to their adherence. Without this, they would be less likely to follow their structured
protocol. The lack of visual aids decreased the frequency and execution of home exercises. Finally,
cost of therapy and multiple associated costs (gym memberships/exercise equipment) were
identified as deterrents. Lack of self-efficacy was not identified as a major issue, likely related to
the high-level athletic nature of this population. In contrast to adult literature, anxiety and
depression were not common themes. This highlights a significant difference between adult and
adolescent populations involved in rehabilitation after elective surgery. These results provide
physicians and physiotherapists with insight into the possible barriers affecting adherence to
physiotherapy in the adolescent population. Consideration of these issues from a patient’s
perspective may lead to improved clinical care and outcomes.
50
CORA P36
Do Differences in the Coronal Alignment of Standard Mechanical Axis-referenced Total Knee
Arthroplasty Affect Quantifiable Measures of Gait?
Jonathan Lau, Queen’s University
Gavin Wood, Amy Morton, Kevin Delusion, Adam Clansey
Purpose: The reference standard for total knee arthroplasty (TKA) alignment has historically been
based on a two-dimensional “mechanical axis” of the knee with the joint surface being parallel to the
ground. Recent studies have placed into question whether this truly affects TKA survivorship and
patient satisfaction. Our study proposes to implement the evolving technology of gait analysis to
determine whether TKA coronal alignment affects objective measures of biomechanical function and
whether this correlates to patient satisfaction and validated knee function scores.
Method: A prospective study of patients receiving unilateral TKAs was performed in which a preoperative gait assessment, full-length standing films and the Oxford knee questionnaire were given
prior to surgery and compared to post-operative measures at six month and one year time points. Post
hoc analysis compared knees that fell into five different categories:
1) Neutral Mechanical Axis (Neutral +/- two degrees of varus or valgus)
2) Varus Alignment (> two degrees of varus and < six degrees of varus)
3) Valgus Alignment (>two degrees of valgus and < six degrees of valgus)
4) Extreme Varus Alignment (> six degrees of varus alignment)
5) Extreme Valgus Alignment (> six degrees of valgus alignment)
These differences were then plotted for differences in joint angles, joint moments, joint reaction forces,
step length, step frequency and timed distances using live three-dimension real time gait analysis.
Results: This project is still in its infancy with only one patient having currently completed their initial
and six month gait study and their one year gait analysis and corresponding long axis x-rays to be
completed well before the CORA conference (June 2016). Five other patients have completed their
initial gait analysis and four (possibly five) patients will have their six month gait study completed by
June. Initial results of our pilot patient are as follows:
The pilot patient’s initial mechanical axis was a subtle 2.3 degrees of varus (post-operative mechanical
alignment is pending). This corresponds to a pre-operative anatomic coronal alignment of 0.5 degrees
of valgus that was corrected to a post-operative alignment of 2.7 degrees of valgus. His self-selected
walking speed did not change at 6 months, but increased by 15% when walking at maximal velocity.
The maximal knee adduction moment in his gait cycle decreased from 0.64 Nm/kg to 0.23 Nm/kg
(occurring at single leg mid-stance). Standard gait analysis joint angle time plots showed increases in
valgus knee angles at all time points post-operatively, closely resembling curves of normal healthy
controls. This disparity was even more pronounced during ascending/descending stair climbing. Finally
the patient’s “timed up and go” test was reduced from 8.93 seconds to 6.62 seconds at 6 months follow
up.
Conclusion: It is our hope that this project will identify the effect coronal TKA alignment has on
quantifiable measures of function and patient satisfaction, while also validating gait analysis as a very
sensitive tool for identifying subtle differences in function and future prosthesis survivorship. Dramatic
differences already have been noted in our pilot patient who had only a two degree correction from preop to post-op.
51
CORA P37
Acute Compartment Syndrome Following Surgical Treatment of Chronic Exertional
Compartment Syndrome: A Case Report
Tanner Dunlop, University of Saskatchewan
William Dust
Purpose: The purpose of this case report is to explore possibility of ACS as a complication of
surgical treatment of CECS. We also explore the skin as a causative/contributing factor to the
development of ACS even after fascial release.
Method: All clinical data regarding this patient was reviewed. A literature review was performed
looking for reports of ACS following the surgical management of CECS.
Results: A 21 year-old male presented with pain and cramping in the right lower leg with activity.
He was diagnosed with exertional compartment syndrome based on exercise stress testing. Failing
conservative management he underwent subcutaneous fasciotomies of the right lower leg anterior
and lateral compartments. Postoperatively, he had a considerable amount of oozing requiring
dressing changes. In the evening, he began experiencing worsening pain and paresthesias to the
dorsum and plantar aspects of his foot. He presented to the emergency department with signs and
symptoms fitting with compartment syndrome. He was taken to the operating room for emergent
fasciotomies and irrigation and debridement. Preoperative compartment pressures were
measured. Anterior compartment measured 47mmHg and the deep posterior compartment
measured 42mmHg with a MAP of 66 and a diastolic blood pressure of 50mmHg. The skin
incisions were connected which effectively released the pressure. A large hematoma was present
and evacuated. This was in the region of Peroneal artery although there was no continued
bleeding. Post-evacuation of the hematoma and release of the skin bridge, the posterior
compartment measured 17mmHG with a MAP of 64 and a diastolic blood pressure of 48mmHg.
The lateral wound was left open. Four hours postoperatively he reported resolution of the pain. The
sensation returned to normal.
There have been no reports in the literature of an ACS as a complication.
There is a correlation between the length of skin incision and the amount of decompression
achieved.
Conclusion: Chronic exertional compartment syndrome of the leg is a source of lower-extremity
pain in military personnel, competitive athletes, and runners. Surgical management includes
subcutaneous fasciotomies of the involved compartments. Hematoma/seroma formation is a noted
complication, however, no reported cases of acute compartment syndrome have been noted. Care
must be taken to achieve hemostasis to avoid post-operative hematoma formation.
52
CORA P38
The STATE of Waiting: A Prospective Human Behavioural Study to Assess Changes in
Health Status in Patients Awaiting Orthopaedic Foot and Ankle Care
Lauren Roberts, University of British Columbia
Kevin Wing, Murray Penner, Alistair Younger, Jeffery Nacht, Jason Sutherland
Purpose: As the Canadian population continues to grow and age, the demand on our system
continues to grossly outweigh the available supply. The subsequent delay that patients have for
scheduled non-emergent orthopaedic surgery can be significant. The effects of such a wait on the
patient’s overall wellbeing and quality of life can also be significant and to our knowledge has not
been quantified in patients waiting for non-emergent foot and ankle orthopaedic care. The present
study will investigate the effect of such a wait time on a patient state of health and well being as
they await Orthopaedic foot and ankle care.
Method: A prospective longitudinal survey design has been implemented to look at the health of
patients waiting for surgical assessment. Factors that will be measured include: acute and chronic
pain, anxiety, depression, patients’ knowledge about their condition, and their desired autonomy in
the decision making process. Study participants are surveyed at using various validated general as
well as condition specific tools at the time of initial F&A Screening Triage (FAST) clinic
consultation, initial orthopaedic surgeon consultation as well as following the initial 6 months of
treatment.
Results: From when data collection began in Sept 2014, 1400 patients have received a mail out of
questionnaire at the time of being referred to the FAST clinic by their general practitioner. As of
Sept 2015, 514 patients (36%) have responded and 5 patients withdrew. Of these 514 patients,
111 (21%) have had their initial FAST visit whereas, 403 (79%) are still presently awaiting their
initial visit. Of those who have had their first visit, 45 (41%) responded to the questionnaire after
their FAST visit.
Conclusion: Based on the evidence available in this area of study in the arthroplasty literature it is
hypothesized that there will be no improvement in health status while waiting for consultation with
the surgeon as measured by condition specific and generic health status instruments. It is
hypothesized that there will be improvement in reported health status following the patient’s
consultation either with the FAST clinic or with an orthopaedic surgeon. We will present the results
of this survey which will illustrate health states over time in a large cohort of foot and ankle patients
as they travel down the assessment and treatment pathway.
53
CORA P39
Perceived vs Real Anterior Glenoid Anchor Placement: A Cadaveric Comparison of Beach
Chair and Lateral Position
Benjamin Jong, University of British Columbia
Jeffrey M. Pike, Patrick Y. Chin, Peter B. Macdonald, William Regan, Treny Sasyniuk, Danny P.
Goel
Purpose: Arthroscopic shoulder stabilization (Bankart repair) can be performed in beach chair
(BC) or lateral decubitus (LD) positions. Surgeons’ perceived location of glenoid anchor placement
may vary depending on position utilized. This study compares perceived glenoid anchor placement
versus actual anchor placement in three views.
Method: This study utilized eight fresh frozen, non-paired cadaveric shoulder specimens. Bone
loss of the anterior glenoid was assessed arthroscopically and two suture anchors were placed in
the anterior glenoid of each shoulder. Following anchor placement, an arthroscopic examination
was performed and recorded with both video and still images of the anchors from three views using
both a 30° and 70° scopes from the posterior beach chair, posterior lateral and anterolateral portal.
Each shoulder was then disarticulated and a sagittal image of the glenoid was obtained with exact
anchor location determined using Image J software and calipers and the clock face method.
The videos and images were sent to six experienced orthopaedic shoulder surgeons for review in a
standardized fashion. Each surgeon was blinded to each other’s findings. For each case, the
surgeon was asked to identify the position of the two anchors on the clock face, and then were
asked to comment on their confidence in each assessment (weak versus strong).
The data will be reviewed descriptively and outliers identified. Accuracy and surgeon agreement
will be determined using kappa and inter-class correlation coefficients. Any identified trends
among LD vs. BC surgeons will be reported.
Results: Video/image review and data collection are ongoing.
Conclusion: To be determined.
54