Relative to the Subtalar Joint, the Calcaneocuboid Joint has a Greater Range of Motion than the Talonavicular Joint in the Coronal Plane
Authors: Thurber Mikaela , Hollister Anne , Olmedo Margaret , Hammer Leslie , Hamilton Kathryn A. 
Published: June 2021

The objective of this study was to determine the range of motion of the calcaneocuboid and talonavicular joints relative to the subtalar joint in 6 locked midfoot positions and 3 locked subtalar joint positions. Eight fresh‐frozen cadaver specimens were acquired from the Willed Body Program at Louisiana State University Health Sciences Center, Shreveport, LA. Specimens included male and female right and left lower legs transected 20 cm inferior to the knee. The interosseous membrane held the tibia and fibula together and the ankle joint was locked in neutral. The axis finder method developed by Hollister et al. (1993) was used to verify the ankle and hindfoot axes of rotation that had been reported by Inman (1969) and Manter (1941), further validating Hollister's method. The same method was then used to identify the calcaneocuboid and talonavicular midfoot joint axes relative to the subtalar hindfoot joint axis. To measure the axes of rotation, an x‐y‐z coordinate system was fixed to the anterior tibia and used as a reference. The midfoot positions included inversion, eversion, dorsiflexion, plantarflexion, abduction and adduction. The subtalar joint positions included inversion, eversion and neutral. Images (6000 × 4000 pixels) were obtained in the coronal plane for midfoot inversion and eversion, in the sagittal plane for midfoot dorsiflexion and plantarflexion and in the axial plane for midfoot abduction and adduction. A computerized drafting program (Rhinoceros, ver. 5) was used to measure the axis angles. The measurements were analyzed using Independent Sample T‐tests (SPSS, ver. 24), with P <0.05 considered statistically significant.The range of motion of each joint was calculated as the absolute value of the difference in the axis angles between two midfoot positions in each subtalar joint position in the same plane. When the subtalar joint was inverted, the calcaneocuboid joint range of motion was 13.87.33° (mean.D.), whereas the talonavicular joint range of motion was 5.64.03°. When the subtalar joint was everted, the calcaneocuboid and talonavicular joint ranges of motion were 12.74.83° and 7.04.16°, respectively. When the subtalar joint was in neutral position, the calcaneocuboid and talonavicular joint ranges of motion were 15.73.89° and 6.572.12°, respectively. In all three subtalar joint positions, the calcaneocuboid joint range of motion was significantly greater than talonavicular joint range of motion (inversion and eversion, P<0.05; neutral P<0.001). In the sagittal and axial planes, the midfoot ranges of motion for dorsiflexion‐plantarflexion and abduction‐adduction exhibited greater variability and therefore did not differ significantly.Results of this study show that when the midfoot is inverted or everted and the subtalar joint is inverted, everted or in neutral position, the calcaneocuboid joint has a greater range of motion than the talonavicular joint. These results could be used to improve midfoot mobility in prosthetics and for correcting gait cycle abnormalities.Support or Funding InformationResearch supported by the Departments of Cellular Biology and Anatomy and Orthopedics at Louisiana State University Health Sciences Center, Shreveport, LA.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.