Download The potential effect of anatomic relationship between the femur and

Surg Radiol Anat (2014) 36:741–746
DOI 10.1007/s00276-014-1266-x
ORIGINAL ARTICLE
The potential effect of anatomic relationship between the femur
and the tibia on medial meniscus tears
Murat Bozkurt · Serhan Unlu · Nurdan Cay ·
Nihal Apaydin · Metin Dogan Received: 4 October 2013 / Accepted: 28 January 2014 / Published online: 11 February 2014
© Springer-Verlag France 2014
Abstract Background The anatomic and the kinematical relationships between the femur and the tibia have been previously
examined in both normal and diseased knees. However,
less attention has been directed to the effect of these relationships on the meniscal diseases. Therefore, we aimed
to investigate the impact of femorotibial incongruence on
both lateral and medial meniscal tears.
Materials and methods A total of 100 images obtained
from MRI of 100 patients (39 males and 61 females) were
included in the study. Diameters of the medial and the lateral femoral condyles, thicknesses of the menisci, and
diameters of the medial and the lateral tibial articular surfaces were measured.
Results The medial meniscus tear was detected in 40
(40 %) patients. However, no lateral meniscus tear was
found. Significant relationships were found between the
diameters of the posterior medial femoral condyle and
the medial tibial superior articular surface and between
M. Bozkurt (*) · M. Dogan Department of Orthopedics and Traumatology, Faculty
of Medicine, Ataturk Training and Research Hospital, Yıldırım
Beyazıt University, Bilkent, Ankara, Turkey
e-mail: [email protected]
S. Unlu Department of Orthopedics and Traumatology, Diskapi Yildirim
Beyazit Training and Research Hospital, Diskapi, Ankara, Turkey
N. Cay Department of Radiology, Faculty of Medicine, Ataturk Training
and Research Hospital, Yıldırım Beyazıt University, Bilkent,
Ankara, Turkey
N. Apaydin Department of Anatomy, Faculty of Medicine, Ankara University,
Sihhiye, Ankara, Turkey
the diameters of the posterior lateral femoral condyle and
the lateral tibial superior articular surface. The mean values for the diameter of the medial condyle of the femur,
the lateral condyle of the femur, the medial superior articular surface of the tibia, and the lateral superior articular
surface of the tibia were found to be significantly higher
in cases with meniscus tear compared to cases without
meniscus tear. However, no significant difference was
present regarding the thicknesses of the medial and the
lateral menisci. A positive relationship between the diameter of the posterior medial femoral condyle and the tibial
medial superior articular surface was found in cases with
(n = 40) (r2 = 0.208, p = 0.003) and without tear (n = 60)
(r2 = 0.182, p = 0.001). In addition, a significant positive
relationship was found between the diameter of the posterior medial femoral condyle and the medial tibial superior
articular surface in cases with and without tear.
Conclusion The impact of femorotibial incongruence on
the medial meniscus tear is important for the understanding
of the lesions.
Keywords Femur · Medial meniscus · Meniscus tear ·
MRI · Tibia
Introduction
The morphology and the kinematics of the femur and the
tibia in the knee have been one of the subjects of anatomical debates. Several studies have shown that the surfaces of the posterior femoral condyles are circular and
their centers can be found reliably [5, 6, 13]. Therefore,
these can be used to track the movement of the femur
relative to the tibia for kinematical studies. This relationship between the kinematics and the morphology of the
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Fig. 1 The measurement of the diameter of the condyle of the femur
knee was originally proposed by Weber et al. [13]. Later,
Iwaki et al. [5] have used MRI to determine the shapes
of the articular surfaces and their relative movements.
They have concluded and confirmed by anatomic dissection that the medial femoral condyle in the sagittal section was composed of the arcs of two circles and the tibia
was composed of two angled flats. On the other hand, the
lateral femoral condyle was composed of a single circular facet similar to the posterior medial facet and the tibia
was flat.
In studies carried out thereafter, morphometric incongruence has been shown to be one of the causes of various
clinical conditions in the knee such as osteoarthritis and
patella–femoral degenerations [8, 9]. However, the role of
the knee morphology on meniscal lesions has not received
much attention. Suganuma [11] has studied the lack of
posteromedial tibiofemoral (PMTF) congruence at full
flexion as a causative factor in isolated medial meniscus
tears. He has concluded that incongruence of the PMTF
articulation at full flexion was considered to be one of the
causes of isolated medial meniscus tear. In another study,
Suganuma et al. [12] have concluded that the addition
of decompression of the posterior segment of the medial
meniscus to meniscal repair of the knee joints with PMTF
incongruence improved both function of the knee joint and
the rate of success of repair of isolated medial meniscus
tears in patients who regularly performed deep flexion.
This finding reveals the importance of detecting the morphologic incongruence in treatment planning of meniscal
lesions.
The aim of this study, therefore, is to evaluate the impact
of femorotibial incongruence in both lateral and medial
meniscus tears.
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Materials and methods
Magnetic resonance images (MRI) of 100 knees of 100
patients performed in two different radiology centers were
randomly selected (39 males and 61 females, mean age:
38). 45 Left and 55 right knees were included in the study.
None of the patients had anterior cruciate ligament rupture
or chondral injury. None of them had a history of previous
knee surgery and any associated diseases.
All scans were performed with Siemens Magnetom
Symphony Maestro Class 1.5 Tesla MRI scanner (Siemens
AG, Erlangen, Germany). With MRI, T1-weighted images
in the sagittal plane (TR/TE 555/20 ms), fat-suppressed
proton density-weighted images in coronal, axial and sagittal planes (TR/TE 3,948–4,443/45 ms) were obtained.
FOV was 15–30 cm, matrix was 192 × 256 pixels and slice
thickness was 4 mm.
MR images were then imported and converted to Materialise’s Interactive Medical Image Control System (MIMICS) (Reverse Modeling Inc., Covina, CA), a general purpose segmentation program for gray value images and for
post-processing of images.
To limit the intra-observer variability, diameters of the
medial and lateral posterior femoral condyles were measured in sagittal planes, where the condyles were spherical
and the biggest in size (Fig. 1). Thicknesses of the menisci
were measured in coronal plane, where the menisci reached
the thickest size (Fig. 2). Diameters of the medial and lateral tibial superior articular surfaces were measured in the
axial plane, where the tibial superior articular surfaces’
shapes were most spherical (Fig. 3). Meniscal pathologies
were assessed by a radiologist blinded to the study protocol. Measurements were repeated at two different times by
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Table 1 The mean values of the measurements
Mean ± SD
Minimum
Maximum
FMEDCON (mm)
FLATCON (mm)
TMEDPL (mm)
TLATPL (mm)
18.83 ± 1.92
18.10 ± 1.99
24.54 ± 2.82
19.95 ± 2.88
15.50
14.15
19.97
14.72
24.35
23.09
30.65
26.27
MEDMTH (mm)
4.84 ± 0.78
3.33
6.81
LATMTH (mm)
5.58 ± 0.86
3.76
7.34
FLATCON Diameter of the lateral condyle of the femur, FMEDCON
diameter of the medial condyle of the femur, LATMTH thickness of
the lateral meniscus, MEDMTH thickness of the medial meniscus,
TLATPL diameter of the lateral superior articular surface of the tibia,
TMEDPL diameter of the medial superior articular surface of the tibia
Fig. 2 The measurement of the thickness of the meniscus
continuous variables. Student’s t test was used to compare
normally distributed continuous variables and the Mann–
Whitney U test for variables without normal distribution.
The χ2 test or the Fisher’s exact test was used to compare
categorical variables. Any correlation was analyzed with
the Pearson analysis. Separate logistic regression analyses were performed to identify univariate predictors of the
medial meniscus tear. The odds ratios (OR) and 95 % confidence intervals (CI) were calculated. A two-tailed p value
of <0.05 was considered to be statistically significant.
An independent ethical board approved the study design.
Results
Fig. 3 The measurement of the diameter of the tibial superior articular surface
the same observer blinded to the study protocol. The mean
values of these measurements were used.
All data were analyzed with the SPSS software version
15.0 for Windows (SPSS Inc., Chicago, IL, USA). Continuous variables were presented as mean ± SD and categorical variables as frequency and percentage. The Kolmogorov–Smirnov test was used to assess the distribution of
The mean values of posterior condylar diameter of the
medial and the lateral femur, the diameter of the tibial
superior articular surface, the thicknesses of the menisci
and meniscus tears are summarized in Table 1. Medial
meniscus tear was detected in 40 (40 %) patients. However,
no lateral meniscus tear was found.
In patients with and without medial meniscus tear,
there was no significant difference regarding the mean age
between two groups (37.7 ± 10.9 vs. 38.3 ± 10.3 years,
p = 0.770, respectively). In addition, it was found that no
significant difference was observed in terms of the mean
age between male and female patients (39.6 ± 9.6 vs.
37.0 ± 11.0 years, p = 0.230, respectively).
There was statistically significant difference between
the diameters of the posterior medial femoral condyle, the
posterior lateral femoral condyle, the medial tibial superior
articular surface and the lateral tibial superior articular surface among male and female patients (p < 0.001). No difference was detected for the thicknesses of the medial and
the lateral menisci (Table 2).
There was a significant difference between the two
groups in terms of medial meniscus tear according to gender [21 (53.8 %) male vs. 19 female (31.1 %), p = 0.024].
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Table 2 The values of the measurements according to gender
FMEDCON (mm)
FLATCON (mm)
TMEDPL (mm)
TLATPL (mm)
MEDMTH (mm)
LATMTH (mm)
Male (n = 39)
Female (n = 61)
p value
20.46 ± 1.89
19.77 ± 1.72
27.00 ± 1.79
22.46 ± 2.44
4.85 ± 0.93
17.79 ± 0.99
17.03 ± 1.30
22.97 ± 2.17
18.34 ± 1.79
4.83 ± 0.69
<0.001
<0.001
<0.001
<0.001
0.893
5.44 ± 0.64
5.66 ± 0.97
0.215
FLATCON Diameter of the lateral condyle of the femur, FMEDCON
diameter of the medial condyle of the femur, LATMTH thickness of
the lateral meniscus, MEDMTH thickness of the medial meniscus,
TLATPL diameter of the lateral superior articular surface of the tibia,
TMEDPL diameter of the medial superior articular surface of the tibia
Fig. 5 Correlation analysis between the diameters of the posterior
lateral femoral condyle and the lateral tibial superior articular surface.
FLATCON diameter of the lateral condyle of the femur, TLATPL
diameter of the lateral superior articular surface of the tibia
Fig. 4 Correlation analysis between the diameters of the posterior medial femoral condyle and the medial tibial superior articular
surface. FMEDCON diameter of the medial condyle of the femur,
TMEDPL diameter of the medial superior articular surface of the tibia
A significant relationship was found between diameters of
the medial femoral condyle and medial tibial superior articular surface (r2 = 0.239, p < 0.001) (Fig. 4). A significant
relationship was found between diameters of the lateral
femoral condyle and lateral tibial superior articular surface
(r2 = 0.413, p < 0.001) (Fig. 5).
There were significant differences between cases with
and without meniscus tear regarding diameters of the
medial femoral condyle, the lateral femoral condyle, the
medial tibial superior articular surface and lateral tibial
superior articular surface. However, there was no significant difference between cases with and without meniscus
tear regarding the thicknesses of the medial and lateral
menisci (Table 3).
The relationship between diameter of the posterior
medial femoral condyle and medial tibial superior articular
surface was investigated between cases with and without
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medial meniscus tear. A positive relationship was found
in cases with (n = 40) (r2 = 0.208, p = 0.003) and without tear (n = 60) (r2 = 0.182, p = 0.001). In other words,
increase in the diameter of the medial femoral condyle was
related with an increase in the diameter of the medial tibial
superior articular surface and vice versa. This relationship
was independent of medial meniscal tear.
In addition, there was a statistically significant difference
between the mean diameter of the medial femoral condyle
and medial tibial superior articular surface in cases with
medial meniscus tear (19.67 ± 1.56 vs. 25.51 ± 2.86 mm,
p < 0.001, respectively).
Lastly, in univariate analysis, the diameters of the medial
condyle of the femur, lateral condyle of the femur, medial
superior articular surface of the tibia and lateral superior
articular surface of the tibia were found to be independent
predictors of the risk of medial meniscus tear (Table 4).
Discussion
The alignment of the femur and the tibia in normal anatomic position and the morphometric characteristics of
these two bones that make up the knee joint have been
evaluated widely by previous studies [3, 4, 7, 10, 14]. It is
known that bone morphology affects both the movement of
the knee joint and the soft tissues. In addition, the morphology of the natural knee joint is very important for designing
total knee arthroplasty and movement sampling [4]. Medial
meniscus posterior tears may be associated with some certain and repeated movements of the knee. These tears may
even be bilateral and the cause has been attributed to the
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Table 3 The values of the measurements according to the presence of the medial meniscus tear
FMEDCON (mm)
FLATCON (mm)
TMEDPL (mm)
TLATPL (mm)
MEDMTH (mm)
LATMTH (mm)
Medial meniscus tear + (n = 40)
Medial meniscus tear − (n = 60)
p value
18.28 ± 1.94
17.58 ± 1.85
23.89 ± 2.63
19.40 ± 2.64
4.84 ± 0.77
19.67 ± 1.56
18.87 ± 1.97
25.51 ± 2.86
20.77 ± 3.07
4.84 ± 0.81
<0.001
0.001
0.005
0.020
0.665
5.58 ± 0.80
5.58 ± 0.96
0.979
FLATCON Diameter of the lateral condyle of the femur, FMEDCON diameter of the medial condyle of the femur, LATMTH thickness of the
lateral meniscus, MEDMTH thickness of the medial meniscus, TLATPL diameter of the lateral superior articular surface of the tibia, TMEDPL
diameter of the medial superior articular surface of the tibia
Table 4 Predictors for medial meniscus tear (univariate analysis)
OR (95 % CI)
p
FMEDCON
FLATCON
TMEDPL
1.527 (1.118–1.964)
1.424 (1.132–1.790)
1.240 (1.062–1.448)
0.001
0.002
0.006
TLATPL
1.186 (1.024–1.374)
0.023
FLATCON Diameter of the lateral condyle of the femur, FMEDCON
diameter of the medial condyle of the femur, TLATPL diameter of the
lateral superior articular surface of the tibia, TMEDPL diameter of the
medial plateau of the tibia
morphometric characteristics of the femoral condyle and
the proximal tibia [2].
Meniscal tears can be classified into two groups, as traumatic and degenerative. The medial and the lateral menisci
in the regions of the posterior and the anterior horn adhere
to the tibia with strong bonds. Therefore, they move as a
part of the tibial superior articular surface [3]. In fact, the
flexion and the extension of the knee mainly take place
between the femoral condyles and the menisci. However,
the tibial rotation with respect to the femur mainly takes
place between the menisci and the tibia [4, 5]. If “screw
home” mechanism is prevented during the flexion and the
extension of the knee, the movements of the menisci are
restricted and the menisci can be torn during a sudden flexion and extension of the knee [5]. The other mechanism of
the meniscus tear is degeneration. A normal meniscus is
elastic, owing to the presence of elastic fibers and this enables the meniscus to resist a particular compression. The
number of elastic fibers starts to decrease with advanced
age and the structure of the meniscus gradually begins to
harden. As the degeneration of the meniscus increases,
meniscal tear can occur during movement [2].
In an MRI study, Bringmann et al. [1] have examined the
translational effect of the antagonist muscles on the menisci
and the femoral condyles during movement from 30° flexion to 90° flexion and seen that they act differently from
one another. The posterior open angle (POA) defined by
Suganuma [11] is important and, especially with deep flexion, the posterior horn of the medial meniscus and even the
middle segment of the medial meniscus between the posteromedial femoral condyle and the posteromedial tibial superior
articular surface were under pressure. Thus, with repetitive
traumas, attention has been drawn to possible damage to the
medial meniscus in patients with tibiofemoral incongruence.
The purpose of our study was to examine the knee joint
under MRI and to investigate the effect of consistence and/
or inconsistence between the distal femoral condyle and the
proximal tibia on the formation of knee lesions. Alignment
between the tibial and the femoral epicondyles was not
very good. Alignment is provided by the relation between
the fibrocartilaginous menisci and the condyles. In addition, the menisci help to distribute the pressure between the
femur and the tibia, to increase flexibility and lubrication.
Adjustment disorder existing in the joint and the changes
in the joint geometry can lead to joint pathologies, particularly meniscus tears. When the results are examined, the
measurements of the diameters of the femoral condyle and
the tibial superior articular surface were significantly different according to gender. The results were lower in female
patients than in male patients. There was no significant
difference between thicknesses of the menisci; however,
it was important to note that all acquisitions were made in
the same phase encoding (to limit variation due to chemical
shift artifact). By gender, significant difference was found
regarding meniscal tear. There was a significant relationship between the posterior medial condyle of the femur
and the medial tibial superior articular surface. There was
also a significant relationship between the posterior lateral
condyle of the femur and the lateral tibial superior articular surface. This relationship was found to be more in the
lateral compartment. In patients with medial meniscus tear,
there was a significant association between the diameter of
the posterior medial femoral condyle and the diameter of
the medial tibial superior articular surface. Random selection of patients caused inappropriate distribution of patients
with and without meniscal tear.
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The incompatibility between the medial femoral condyle
and the medial tibial superior articular surface is associated
with joining morphometries of two surfaces.
An incompatibility on the background can lead to some
injury in the knee. Repetitive traumas can also lead to femorotibial incongruence with time. In this study, the femorotibial incongruence evaluated was found to be associated
with medial meniscus lesions, especially by revealing the
posterior offset in the diameter of the femoral condyle.
Therefore, increased posterior offset by morphometric
changes of the posterior femoral condyle leading to many
problems that can result in arthrosis and loss of flexion in
the knee is thought to be the most important reason.
In conclusion, femorotibial incongruence can be one of
the reasons for many clinical problems, especially medial
meniscus injuries, and an important trigger for developing
osteoarthrosis.
Conflict of interest The authors declare that they have no conflict
of interest.
References
1. Bringmann C, Eckstein F, Bonél H, Englmeier KH, Reiser M,
Graichen H (2000) A new in vivo technique for 3D analysis of
the translation of femoral condyles and the menisci responding to
antagonistic muscle forces. Biomed Tech (Berl) 45:258–264
2. Cox CL, Deangelis JP, Magnussen RA, Fitch RW, Spindler KP
(2009) Meniscal tears in athletes. J Surg Orthop Adv 18:2–8
3. Elias SG, Freeman MA, Gokcay EI (1990) A correlative study of
the geometry and anatomy of the distal femur. Clin Orthop Relat
Res 260:98–103
13
Surg Radiol Anat (2014) 36:741–746
4. Flandry F, Hommel G (2011) Normal anatomy and biomechanics
of the knee. Sports Med Arthr 19:82–92
5. Iwaki H, Pinskerova V, Freeman MA (2000) Tibiofemoral movement 1: the shapes and relative movements of the femur and tibia
in the unloaded cadaver knee. J Bone Jt Surg Br 82:1189–1195
6. Kurosawa H, Walker PS, Abe S, Garg A, Hunter T (1985) Geometry and motion of the knee for implant and orthotic design. J
Biomech 18:487–499
7. Martelli S, Pinskerova V (2002) The shapes of the tibial and
femoral articular surfaces in relation to tibiofemoral movement. J
Bone Jt Surg Br 84:607–613
8. Matsuda S, Miura H, Nagamine R, Mawatari T, Tokunaga M,
Nabeyama R, Iwamoto Y (2004) Anatomical analysis of the
femoral condyle in normal and osteoarthritic knees. J Orthop Res
22:104–109
9. Matsui Y, Kadoya Y, Uehara K, Kobayashi A, Takaoka K (2005)
Rotational deformity in varus osteoarthritis of the knee: analysis
with computed tomography. Clin Orthop Relat Res 433:147–151
10. Patel VV, Hall K, Ries M, Lotz J, Ozhinsky E, Lindsey C, Lu
Y, Majumdar S (2004) A 3D MRI analysis of knee kinematics. J
Orthop Res 22:283–292
11. Suganuma J (2002) Lack of posteromedial tibiofemoral congruence at full flexion as a causative factor in isolated medial meniscal tears. J Orthop Sci 7:217–225
12.Suganuma J, Mochizuki R, Yamaguchi K, Inoue Y, Yamabe
E, Ueda Y, Fujinaka T (2010) Cam impingement of the posterior femoral condyle in medial meniscal tears. Arthroscopy
26:173–183
13. Weber TG, Harrington RM, Henley MB, Tencer AF (1997) The
role of fibular fixation in combined fractures of the tibia and fibula: a biomechanical investigation. J Orthop Trauma 11:206–211
14. Zuffi S, Leardini A, Catani F, Fantozzi S, Cappello A (1999) A
model-based method for the reconstruction of total knee replacement kinematics. IEEE Trans Med Imaging 18:981–991