Three-dimensional analysis of talar trochlea morphology: Implications for subject-specific kinematics of the talocrural joint.
Three-dimensional (3D) behavior of the talocrural joint is primarily determined by the articular surface morphology of the talar trochlea and tibiofibular mortise. However, morphological features of the anterior and posterior regions of the talar trochlea remain unclear. The objectives of this study were to evaluate anterior and posterior radii of the medial and lateral talar trochlea and to estimate subject-specific kinematics of the talocrural joint. Fifty dry tali were scanned using computed tomography to create 3D bone models. Radii of curvature of the anterior and posterior region at both the medial and lateral trochlea were calculated. Orientations of the dorsiflexion and plantarflexion axis passing through the centers of the circles fitted to the anterior region of the medial and lateral trochlea and through the centers of the circles fitted to the posterior region of the medial and lateral trochlea were evaluated, respectively. The anterior radius of the medial trochlea was significantly smaller than that of the lateral trochlea by a mean of 7.8 mm (P < 0.001). The posterior radius of the medial trochlea was larger than that of lateral trochlea in 30 samples (60%) and vice versa in 20 samples (40%). Unilateral asymmetric shape of anterior trochlea would induce external rotation of the talus during ankle dorsiflexion, whereas bilateral asymmetric shape of posterior trochlea would induce opposite axial rotations among subjects during ankle plantarflexion, which would help the physical therapists to restore talocrural joint motions to ideal state for patients with ankle injuries. Clin. Anat. 29:1066-1074, 2016. © 2016 Wiley Periodicals, Inc.
Department of Rehabilitation, Hokkaido Obihiro Kyokai Hospital, Obihiro, Hokkaido, Japan. nozakis@sapmed.ac.jp.|Second Division of Physical Therapy, School of Health Sciences, Sapporo Medical University, Sapporo, Hokkaido, Japan. nozakis@sapmed.ac.jp.
Shuhei
S
Nozaki
Second Division of Physical Therapy, School of Health Sciences, Sapporo Medical University, Sapporo, Hokkaido, Japan.
Kota
K
Watanabe
Second Division of Physical Therapy, School of Health Sciences, Sapporo Medical University, Sapporo, Hokkaido, Japan.
Masaki
M
Katayose
D000328:Adult; D000843:Ankle Joint / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology; D001696:Biomechanical Phenomena; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012016:Reference Values; D013628:Talus / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology; D014057:Tomography, X-Ray Computed; D055815:Young Adult
dorsiflexion; image-based bone models; plantarflexion; radius; talus; trochlea