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FOOT & ANKLE INTERNATIONAL
Copyright  2012 by the American Orthopaedic Foot & Ankle Society
DOI: 10.3113/FAI.2012.0602
Functional Results of Posterior Tibial Tendon Reconstruction, Calcaneal
Ostetomy, and Gastrocnemius Recession
Joseph X. Kou, MD; Mamtha Balasubramaniam, MS; Matthew Kippe, MD; Paul T. Fortin, MD
Walnut Creek, CA
ABSTRACT
Level of Evidence: III, Prospective Case Series
Background: This study aimed to assess and provide prospective outcome data following reconstruction of Stage II posterior
tibial tendon insufficiency, as well as evaluate the effect of
reconstruction with gastrocnemius recession on plantarflexion
strength. Methods: A prospective evaluation of 24 patients
undergoing reconstruction for Stage II posterior tibial tendon
insufficiency was granted IRB approval. The reconstructive
procedures consisted of a flexor digitorum longus transfer,
medial displacement calcaneal osteotomy, lateral column lengthening, and gastrocnemius recession. Patients were asked to
complete multiple outcome measures preoperatively, 6 months,
1 year, and 2 years postoperatively. A dynamometer was utilized
to evaluate peak torque plantarflexion preoperatively, 6 months,
and 1 year postoperatively. Results: In the study, 14 patients
completed preoperative surveys, and 23 patients had 2-year
followup. Patients were highly satisfied with the results of their
surgery. All outcome measures showed statistically significant
improvement. Improvement was seen at 6 months, but results
continued to improve at the 1-year mark. By the second year,
improvement largely reached a plateau. Biodex testing showed
no loss of plantarflexion strength after reconstruction and
gastrocnemius recession. Conclusion: Reconstruction of the flexible adult acquired flatfoot with FDL transfer, double calcaneal
osteotomy, and gastrocnemius recession yielded excellent functional results for the treatment of Stage II posterior tibial tendon
insufficiency. Plantarflexion weakness was not found to be a
concern. A good functional outcome can be anticipated after
the early postoperative period. However, it should be expected
to take at least 1 year for maximal benefit.
Key Words: Posterior Tibial Tendon; Flatfoot; Gastrocnemius
Recession; Calcaneal Osteotomy; Lateral Column Lengthening
INTRODUCTION
The acquired adult flatfoot deformity (AAFD) is a known
entity which causes substantial morbidity. AAFD consists of
hindfoot valgus, loss of the medial arch, forefoot abduction,
and attenuation of the posteromedial soft tissues, including
the posterior tibial tendon (PTT). There are numerous treatment options for the flexible AAFD or Stage II posterior tibial tendon dysfunction as described by Johnson and
Strom.11 However, there is currently a paucity of strong,
prospective Level I or II studies which support these treatment options.
Many studies with Level IV evidence support medializing calcaneal osteotomy with posterior tibial tendon
augmentation.7,9,16,17,22,25,28 While good results have been
shown with medializing calcaneal osteotomies and PTT
augmentation, other bony procedures have been used in
conjunction to treat the underlying flatfoot deformity and
protect soft-tissue reconstructions. Lateral column lengthening procedures which address peritalar dorsolateral subluxation and medial column stabilization procedures8 which
address collapse at the first tarsal-metatarsal joint and forefoot supination from lateral column lengthening, have been
utilized in addition to PTT augmentation and medializing
calcaneal osteotomies. Studies have shown the ability of
these procedures to attain radiographic correction of the
deformity,4 but few studies with only Level IV evidence have
demonstrated good functional results with double calcaneal
osteotomies with PTT augmentation.13,25 Van Der Krans
et al.27 has demonstrated with Level II evidence that good
results can be obtained with calcaneocuboid distraction
arthrodesis, posterior tibial tendon augmentation, and percutaneous Achilles tendon lengthening. However, based on
the present literature, insufficient evidence exists to make
a specific treatment recommendation for or against the use
No benefits in any form have been received or will be received from a commercial
party related directly or indirectly to the subject of this article.
Corresponding Author:
Joseph Xavier Kou, MD
Muir Orthopaedic Specialists
Orthopaedic Surgery
2405 Shadelands Dr.
Walnut Creek, CA 94598
E-mail: [email protected]
For information on pricing and availability of reprints, email [email protected]
or call 410-494-4994 x232.
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FUNCTIONAL RESULTS OF PTT RECONSTRUCTION
of double calcaneal osteotomies in the operative management
of Stage II AAFD.18
Although the actual role of equinus contracture in AAFD
is controversial, it is known to be associated with the
disease.26 As such, many AAFD reconstructive procedures
include percutaneous lengthening of the Achilles tendon
or gastrocnemius recession. Loss of strength after percutaneous Achilles lengthening is a concern.12,24 The use
of gastrocnemius recession as an alternative is gaining
popularity in the hopes of averting loss of plantarflexion
strength. Computer simulations have suggested nearly normal
moment-generating characteristics could be restored with
gastrocnemius recession compared to significant loss of
moment-generating capacity with Achilles lengthening.5 The
clinical effect of gastrocnemius recession on plantarflexion
strength has yet to be fully addressed. Brodsky et al.3 has
shown increased ankle power at push-off after posterior
tibial tendon reconstruction; however, only three of the 12
patients had gastrocnemius recessions. Sammarco et al.21
demonstrated an initial decrease in plantarflexion strength
after gastrocnemius recession, but with improvement over
time. However, the numbers generated in this study were in
comparison to the postoperative contralateral extremity and
not the preoperative ipsilateral limb.
The purpose of this study was two-fold. The first was to
prospectively determine the functional results, using validated outcome measures, of PTT reconstruction with FDL
transfer to the navicular, medializing calcaneal osteotomy,
lateral column lengthening, and gastrocnemius recession.
The second was to prospectively determine the effect of
these procedures on plantarflexion strength. We hypothesized
that there would be an improvement in functional outcome
measures following reconstruction and that there would not
be a significant loss in plantarflexion strength despite gastrocnemius recession.
Procedures that all patients underwent were: 1) gastrocnemius recession through a longitudinal incision along the
medial side of the leg at the level of the musculotendinous junction; 2) medial displacement calcaneal osteotomy
through the posterior one-third of the calcaneus; 3) lateral
column lengthening with approximately 1 cm tricortical iliac
crest allograft wedge placed 1 cm proximal to the calcaneocuboid joint (stabilized with one or two 3.5-mm cortical
screws); and 4) FDL transfer to the navicular. The PTT
was only excised if found to be extremely attenuated and
nonfunctional. Twelve patients with first tarsal-metatarsal
joint instability and/or arthrosis underwent medial column
stabilization (Figures 1 through 4). Associated procedures
included two patients who had correction of hallux valgus,
and one patient with a fibular stress fracture treated with
internal fixation (Figure 2).
Postoperative management involved removal of splint and
application of a bivalved short leg cast on postoperative day
2. The cast was removed at 1 week postoperatively for wound
check and then re-applied, taking care to maintain a plantigrade foot. Patients were made nonweightbearing for a total
of 6 weeks, and then placed in a walker boot to progressively
weight bear over 1 month. Physical therapy was initiated as
soon as weightbearing was allowed. Postoperative orthotics
were not used. All patients were treated with coumadin for
1 month postoperatively, maintaining an INR between 2 and
3 for DVT prophylaxis.
Patients underwent both pre- and postoperative evaluations. Each evaluation consisted of four outcome measure
questionnaires and a measurement of strength with an isokinetic dynamometer. A visual analog foot and ankle scale
(VAS) was administered to assess pain, mobility, strength,
daily function, overall health, and satisfaction with the
results of the surgery on a scale from 0 to 10. The
foot and ankle outcome survey (FAOS)19 was utilized to
assess pain, symptoms, and ability to function in activities
of daily living (ADL). The Rowan foot pain assessment
questionnaire (ROFPAQ)20 validated for chronic foot pain,
assessed foot pain with an affective, cognitive, and sensory
subscale. The SF-1229 was also utilized, which measured
both a physical (PCS) as well as a mental component
(MCS).
Evaluation of plantarflexion strength was accomplished
with a Biodex dynamometer. Isokinetic dynamometer testing
with the Biodex has been shown to have high test-retest
reliability10 and superiority compared to manual muscle
testing.1 Peak torque ankle plantarflexion measurements were
taken with the knee in full extension and 90 degrees flexion
of both the ipsilateral and contralateral extremity.
Evaluations were conducted at four time intervals. The
first evaluation was administered preoperatively, followed by
evaluations at 6 months, 1 year, and 2 years postoperatively.
Biodex testing was performed preoperatively, 6 months, and
1 year, postoperatively. Additionally, pre- and postoperative
radiographic measurements of hindfoot valgus, talo-first
MATERIALS AND METHODS
IRB approval was obtained for the study group, which
consisted of 24 consecutive patients with Stage II PTT
insufficiency treated operatively by one fellowship-trained
orthopaedic foot and ankle surgeon between September 2004
and January 2006. Of the 24 patients, seven were male and
17 were female. The average age was 60.9 years with a range
of 26 to 81 years of age.
All patients had Stage II disease demonstrated by pain
along the course of the PTT, weakness during single
heel rise, weakness with manual inversion resistance, and
flexible deformities involving pronation and abduction at
the transverse tarsal joint with valgus angulation of the
heel. All patients had failed conservative treatment with
shoe modifications, foot orthoses, AFO support, and antiinflammatory medications. Exclusion criteria included neuropathic arthropathy and seropositive arthritis.
Copyright  2012 by the American Orthopaedic Foot & Ankle Society
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Fig. 1: Preoperative radiographs of Stage II AAFD with midfoot collapse and fibular stress fracture.
Fig. 2: Postoperative radiographs of same patient with double calcaneal osteotomy, first TMT fusion, and fixation of fibular stress fracture.
Fig. 3: Preoperative radiographs of stage II AAFD with significant midfoot arthrosis and collapse.
metatarsal angle, and talo-navicular coverage angle, presence
of calcaneocuboid arthritis, and presence of lateral column
pain were recorded.
In this study, 24 patients enrolled in the study were able to
obtain a preoperative biodex study. Twelve patients followed
up for a biodex study at 6 months, and 17 patients followed
up for a biodex study at 1-year postop. Fourteen patients
completed the four outcome measure surveys preoperatively.
Twelve patients completed the outcome measure surveys
at 6 months postop, 20 patients completed the outcome
measure surveys at 1 year postop, and 23 patients completed
the outcome surveys at 2 years postop. No patients were
Copyright  2012 by the American Orthopaedic Foot & Ankle Society
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FUNCTIONAL RESULTS OF PTT RECONSTRUCTION
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Table 1: Patient Outcome Data Scoring Availability
Patient
Preop
6 Month
12 Month
24 Month
1 2 3 4
X
X
X X
X
X X
X X X X
5
X
X
X
X
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
X
X
X X
X
X
X
X X X X
X X X X X
X X
X
X
X
X X X X X X X X X X
X X X X X
X
X X X X X X X X X X X X X X X X X
completely lost to followup. Detailed outcome data availability is summarized in Table 1.
Statistical analysis
The FAOS, ROFPAQ, SF-12, and VAS were all administered at each of the four time points: preoperatively, 6
months, 1 year, and 2 years postoperatively. At each time
point, the responses to the questions in each questionnaire
were scored according to the scoring algorithm specified for
that questionnaire. This included the creation of subscales
based on grouping specific questions within each questionnaire at each time point.
Patients’ responses to each of the questions across the
four time points were not independent and were, in fact, all
highly correlated. Hence each subscale and other responses
were analyzed using generalized linear models with time as
a nominal predictor and the responses at the preoperative
timepoint as the reference level. Multiple comparisons were
performed using Bonferroni adjustment.
All data were first assessed using numerical and graphical
techniques to determine if they met the distributional assumptions of the statistical tests being used to analyze them.
Based on this preliminary assessment, parametric, nonparametric or exact statistical tests were used to analyze the
data. Continuous variables were summarized using mean ±
standard deviation, median, and inter-quartile range (IQR).
Categorical variables were summarized using frequencies
and percentages.
P values less than an alpha of 0.05 (Probability of Type I
Error) were considered statistically significant.
Fig. 4: Postoperative radiographs of same patient with double calcaneal
osteotomy and midfoot fusion.
Post-hoc power analysis
In this longitudinal study, patients served as their own
controls as their post-operative responses were compared to
that at pre-op. A power analysis was performed in accordance with the repeated measures study design with one
factor (Time) based on one group. Based on this computation,
a minimum of 12 subjects when measured repeatedly four
times would have achieved 99.5% (approximately 100%)
power to test the factor based on a Geisser-Greenhouse
Corrected F Test 6,14,15 with a 5% significance level. The
actual effect standard deviation was 0.56 (an effect size of
1.60). This study had 24 patients and hence was adequately
powered to test the differences between the pre- and postoperative and time points for the various outcomes measured.
RESULTS
Complications and additional procedures included seven
hardware removals, one calf DVT, one wound dehiscence
that healed with local wound care, and one delayed wound
healing which required 4 weeks of daily dressing changes
until healing was achieved.
Preoperatively, 18 (75%) patients were found to have
subfibular impingement pain (tenderness to palpation distal
to the tip of the fibula). No patient had preoperative
radiographic evidence of subtalar arthritis. Nineteen (76%)
patients had complaints of lateral column pain at 6 months
postop. This number dropped to seven (28%) at 1 year
and three (12%) by 2 years. No patient had evidence of
calcaneocuboid arthritis preoperatively. At 2 years postop,
nine patients (36%) had evidence of degenerative changes
(defined as joint space narrowing and presence of marginal
osteophytes on radiographs) at the calcaneocuboid joint.
None of these nine patients had complaints of lateral column
pain at latest followup.
Medial column stabilization was performed as an adjunct
procedure in approximately 50% of the patients. The difference in outcome measures between those who had medial
column stabilization procedures and those that did not were
compared and not found to be statistically significant (p >
0.05) on any of the outcome measures. Therefore, all conclusions were consistent with those made without taking medial
column stabilization into account. For the sake of simplicity
and clarity, only results without this stratification were
presented in this study.
Copyright  2012 by the American Orthopaedic Foot & Ankle Society
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Table 2: VAS Results
Preop Mean ± SD,
Median (IQR)
Pain
Mobility
Strength
Function
Overall Health
5.2
4.8
6.5
7.0
4.8
4.6
5.6
6.2
6.4
6.3
± 2,
(1.5)
± 2.0,
(2.8)
± 2.3,
(3.8)
± 2.1,
(3.4)
± 2.4,
(3.4)
Satisfaction with
results of surgery
Average at
6-Month Mean ± SD,
Median (IQR)
Average at
1-year Mean ± SD,
Median (IQR)
2.7 ± 2.5,
2.1 (2.8)
7.8 ± 1.8,
8.1 (1.6)
7.3 ± 1.5,
7.6 (1.95)
7.9 ± 2.1,
8 (2.5)
7.6 ± 2.1,
7.9 (3.1)
8.8 ± 1.5,
9.5 (2.5)
1.0 ± 1.1,
0.5 (1.4)
8.6 ± 1.8,
9 (2)
8.1 ± 1.5,
8.2 (2.5)
8.7 ± 1.3,
8.7 (2)
9.0 ± 1.6,
9.8 (1.5)
9.3 ± 1.1,
10 (1)
Average at
2-year Mean ± SD,
Median (IQR)
1.1
0.5
8.7
9.3
8.1
8.4
8.7
9.5
8.7
9.4
8.9
9.8
± 1.4,
(1.8)
± 1.5,
(1.9)
± 1.9,
(1.7)
± 1.6,
(2.6)
± 1.7,
(1.3)
± 1.8,
(1.2)
Table 3: FAOS, ROFPAQ, and SF-12 Results
Preop
Mean ± SD,
Median (IQR)
FAOS pain
FAOS symptoms
FAOS activities of
daily living
ROFPAQ sensory
ROFPAQ affective
ROFPAQ cognitive
SF-12 Physical
Component
60.3 ± 17.9,
59.7 (19.4)
66.8 ± 22.0,
73.2 (35.7)
65.5 ± 20.2,
67.5 (30)
2.5 ± 0.5,
2.5 (0.6)
3.3 ± 0.7,
3.3 (1.0)
3.1 ± 0.5,
3 (0.6)
35.9 ± 10.8,
32.2 (12.5)
6-Month
Mean ± SD,
Median (IQR)
70.4 ± 20.5,
63.9 (30.6)
64.9 ± 15.4,
64.3 (16.1)
77.7 ± 17.3,
78.3 (36.7)
2.1 ± 0.7,
1.9 (1.0)
2.5 ± 0.7,
2.4 (1.0)
2.4 ± 0.6,
2.4 (0.8)
41.0 ± 9.7,
39.5 (11.8)
1-Year
Mean ± SD,
Median (IQR)
86.7 ± 10.5,
87.5 (19.4)
85.8 ± 11.0,
89.3 (16.1)
90.6 ± 8.5, 91.7
(16.7)
1.8 ± 0.3,
1.9 (0.5)
2.0 ± 0.6,
2.0 (0.8)
1.8 ± 0.5,
1.9 (0.7)
49.4 ± 8.9,
48.7 (10.8)
2-Year
Mean ± SD,
Median (IQR)
87.3 ± 12.3,
91.7 (19.4)
85.6 ± 12.2,
85.7 (17.9)
89.7 ± 10.6,
93.3 (15)
1.7 ± 0.4,
1.7 (0.5)
2.0 ± 0.77,
2.1 (1.1)
1.7 ± 0.7,
1.7 (0.9)
47.2 ± 10.1,
51.3 (15.9)
FAOS, foot and ankle outcome survey; ROFPAQ, Rowan foot pain assessment questionnaire.
The average preoperative hindfoot valgus of 15.6 degrees
improved to 4.1 degrees at 2 years postop. The average
preoperative talo-first metatarsal angle of −25.0 degrees
corrected to 9.1 degrees at 2 years postop. The average
preoperative talo-navicular coverage angle of 27.7 degrees
was corrected to 8.7 degrees at 2 years postop.
The results of the outcome measure questionnaires (VAS,
ROWAN, FAOS, SF-12) are summarized in Tables 2 and 3.
The data is organized into graph form in Figures 5 through 8.
Statistical data was additionally run to determine if age, the
presence of lateral column pain, calcaneocuboid arthritis, the
use of a medial column fusion, preoperative distal midfoot
collapse, and valgus tibiotalar joint tilt had any significant
effect on functional outcome scoring. No statistically significant difference (all p > 0.05) was found to suggest that any
of these variables had any significant effect on outcome.
Preoperative average plantarflexion strength with a fully
extended knee in the operative extremity was found to be
Copyright  2012 by the American Orthopaedic Foot & Ankle Society
Foot & Ankle International/Vol. 33, No. 7/July 2012
FUNCTIONAL RESULTS OF PTT RECONSTRUCTION
Fig. 5: VAS results.
Fig. 6: FAOS results.
Fig. 7: ROFPAQ results.
Copyright  2012 by the American Orthopaedic Foot & Ankle Society
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Fig. 8: SF-12 Results (Physical Component).
14.1 Nm, SD = 12.7. At 6 months, this value increased to
15.0 Nm, SD = 6.9 (p = 1.0000). At 1 year, it increased
to 21.3 Nm, SD = 11.7 (p = 0.16). Preoperative average
plantarflexion strength with the knee flexed 90 degrees in
the operative extremity was found to be 14.0 Nm, SD =
9.2. At 6 months, strength increased to 16.4 Nm, SD =
8.3 (p = 1.0000), and then increased to 22.4 Nm, SD =
9.8 (p = 0.0246) after 1 year. For comparison purposes,
plantar flexion strength of the contralateral nonoperative
extremity (knee flexed and extended) was measured at all
three time points, and no statistically significant difference
was found between all 3 time points. With a fully extended
knee, the preoperative difference between extremities was a
36% weaker operative extremity. At 6 months, the difference increased to 41%, but at 1 year the difference dropped
to only 6%. When the knee was flexed 90 degrees, the preoperative difference in strength between extremities was 35%
weaker in the operative extremity. By 6 months that difference dropped to 17%, and by 1 year there was only a 4%
difference. Biodex plantarflexion strength results are summarized in Table 4 and Figures 9 and 10.
DISCUSSION
Many retrospective studies have demonstrated that the
AAFD can be treated surgically with good results. There
are numerous options that the surgeon has to select from
when treating the AAFD. Of course, with many options,
there are also many opinions on which treatment regimen
has the best results. Despite the many options and recommendations in the literature, to our knowledge there is no
prospective comparative data in the North American literature to support a specific surgical treatment of the AAFD.
This study provides prospective data on the outcome of PTT
reconstruction using FDL transfer, medializing calcaneal
osteotomy, lateral column lengthening, and gastrocnemius
recession. The results of our data demonstrate statistically
significant improvement of all outcome measures (VAS,
FOAS, ROFAPQ, SF-12) and their subscales at 1 year, with
maintenance of that significant improvement at 2 years. Additionally, patients had a high level of satisfaction with the
results of the procedure. As a result, we conclude that the
treatment regimen described in this study is an excellent
option for the treatment of the AAFD.
It should be noted that while improvements were seen
in the early 6-month postoperative period, many outcome
measure results were not statistically significant until the 1year mark. The surgeon and the patient should be aware
that a good functional outcome can be seen in the early
postoperative period. However, it should be expected to take
at least 1 year for the maximum benefit from the procedure
to be appreciated.
Isokinetic dynamometry evaluation in this study did not
demonstrate any statistically significant loss of plantarflexion
strength when combining a gastrocnemius recession with
PTT reconstruction. In fact, there was a progressive improvement in plantarflexion strength at 1 year when compared
to preoperative strength of the ipsilateral extremity. Plantarflexion strength with the leg fully extended would seem
to isolate gastrocnemius strength more accurately than with
the knee flexed, which relaxes the gastrocnemius. When
comparing strength to the contralateral extremity, our 6month results were similar to Sammarco et al.21 in which
the early postoperative period saw increased plantarflexion
weakness with a fully extended leg when compared to the
contralateral extremity. However, similar to Sammarco’s
study, at 1 year the situation changed and the operative
extremity strength improved. When the knee was flexed,
there was no loss in plantarflexion strength postoperatively,
and this was likely due to gastrocnemius being relaxed. In
Table 4: Biodex Plantarflexion Strength (Nm) results
Preop
Mean ± SD,
Median (IQR)
Leg extended operative leg
Leg extended contralateral
leg
Flexed 90 operative leg
Flexed 90 contralateral leg
6 months
Mean ± SD,
Median (IQR)
1 year
Mean ± SD,
Median (IQR)
14.1 ± 12.7, 9.8 (10.5)
19.2 ± 14.5, 15.2 (16.7)
15.0 ± 6.9, 15.3 (19.2)
21.2 ± 10.3, 23.1 (15.7)
21.3 ± 11.7, 21.8 (15.5)
22.6 ± 11.8, 21.7 (18.7)
14.0 ± 9.2, 11.9 (12.8)
18.9 ± 10.2, 20.0 (17.5)
16.4 ± 8.3, 16.7 (12.1)
19.2 ± 8.3, 18.9 (14.8)
22.4 ± 9.8, 18.9 (12.3)
23.3 ± 13.2, 21.2 (20.9)
Copyright  2012 by the American Orthopaedic Foot & Ankle Society
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FUNCTIONAL RESULTS OF PTT RECONSTRUCTION
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Fig. 9: Plantarflexion strength of the operative extremity.
this study, at 1 year after surgery the operative extremity
was 6% weaker than the contralateral extremity, compared
to being 36% weaker preoperatively. It should be noted
that after 1 year, the ankle was not left weaker compared
to preoperative measurements of plantarflexion despite the
lengthening from a gastrocnemius recession.
Studies have demonstrated increased lateral forefoot pressures after lateral column lengthening procedures.2,23 As
a result, there are concerns about lateral column pain
and subsequent calcaneocuboid arthritis after lateral column
lengthening. Many patients in this study (75%) presented
with lateral column pain preoperatively. We believe the
source of this pain is from subfibular impingement due to
the planovalgus deformity seen in PTTD. The subfibular
impingement is relieved after deformity correction through
calcaneal osteotomies, but lateral column pain persisted postoperatively on initial followup. In this study there was a
76% incidence of lateral column pain at 6 months postop.
However, this number dropped to 28% at 1 year and 12%
Fig. 10: Plantarflexion weakness in comparison to contralateral extremity.
by 2 years. Although no patient had evidence of calcaneocuboid arthritis preoperatively, at 2 years postop, 36%
patients had evidence of degenerative changes at the calcaneocuboid joint. It is interesting to note that none of the
patients who developed calcaneocuboid arthritis complained
of lateral column pain. Although the patients with postoperative calcaneocuboid arthritis did not have pain 2 years
postoperatively, there is reason for concern that they may
eventually develop arthritic pain. We believe initial postoperative lateral column pain was from the change in
mechanics from the calcaneal osteotomies performed. Preoperative subfibular impingement pain was usually tenderness at the distal tip of the fibula, whereas postoperative
lateral column pain manifested as tenderness at the anterior
calcaneal process/cuboid/fifth metatarsal base. We theorize
that the resultant preferential lateral overload and supination
is the cause of initial lateral column pain, but the eventual
normalization of motion and gait pattern over 1 to 2 years is
why lateral column pain resolved in most patients and was
not an issue for 88% of the patients in this study at 2 years.
The development of calcaneocuboid arthritis would seem to
confirm increased lateral column pressure, but longer-term
followup is needed to determine if this increased pressure is
clinically relevant in terms of manifesting as chronic pain.
Our study design does have limitations. Preoperative
data points are incomplete since we were only able to
obtain pre-op evaluations on 14 of the 25 patients. We are
also missing 2-year followup on one patient. The study
size of 25 patients was a sample of convenience, and
power analysis was performed ‘post-hoc.’ The FAOS was
validated for use in those with rheumatoid arthritis. The
use of the FAOS outcome measure, as well as the VAS
Copyright  2012 by the American Orthopaedic Foot & Ankle Society
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was not validated specifically to those with PTTD, and is
considered a weakness of the use of these outcome measures.
Gastrocnemius recession was an adjunct procedure and not
done in isolation. As a result, weakness from the procedure
may be masked by increased plantarflexion strength from the
FDL transfer or less pain. Percutaneous Achilles lengthening
is a popular treatment for equinus contracture, but we are
unable to compare it to gastrocnemius recession since no
Achilles lengthenings were performed in the study. The
study design did not include a randomized, non-surgical
control group. Also, it is not possible to determine whether
there was any benefit to double calcaneal osteotomy over
a single osteotomy since no comparisons were made. The
adjunct procedure of medial column stabilization could be
considered a confounding variable to the results of this study.
A complete statistical analysis of this data was performed
using medial column stabilization as a binary predictor and
no statistically significant differences were found in any of
the outcome measures. Although the possibility exists of a
Type I error, all conclusions were consistent with those made
without taking medial column stabilization into account. For
the sake of simplicity and clarity, only results without this
stratification were presented in this study. Finally, further
long-term followup is needed to evaluate for maintenance of
correction and relief of symptoms.
6.
7.
8.
9.
10.
11.
12.
13.
14.
CONCLUSION
15.
The prospective results of this study make a strong
argument for the role of FDL transfer, double calcaneal
osteotomy, and gastrocnemius recession in the management
of Stage II AAFD. The inclusion of gastrocnemius recession
allowed the surgeon to address equinus contracture without
the need for concern about plantarflexion weakness after the
reconstruction. The surgeon and patient should be aware that
a good functional outcome can be anticipated after the early
postoperative period, and that further improvements in pain
and functionality continue for at least 1 year postoperatively.
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