Ankle and knee joint differences exist despite restoration of acceleration performance after Achilles tendon repair.

Objectives

The aim was to determine whether AT repair influences acceleration performance, joint kinetics and kinematics compared to controls, and whether between-limb differences differ between the groups.

Design

Cross Sectional Study.

Setting

3D Biomechanics Laboratory.

Participants

45 participants (23 post AT repair, 22 controls) completed 3 maximum effort reactive sprint accelerations on each leg. MAIN OUTCOME MEASURES Spatiotemporal, Lower limb joint kinetic and kinematics.

Results

Significant effects of group were observed for several biomechanical variables with the AT repair group demonstrating reduced peak negative ankle power (p < .001, ηp2 = 0.23), reduced ankle positive work (p = .009, ηp2 = 0.08), reduced ankle dorsiflexion range of motion (p = .04, ηp2 = 0.04), increased knee positive power (p = .04, ηp2 = 0.04), and reduced vertical average ground reaction force (p = .007, ηp2 = 0.08). Significant group × limb interactions were identified for ankle positive work (p = .025, ηp2 = 0.09). No significant effect of group or group × limb interaction was observed for time to complete the task.

Conclusions

These effects indicate a reduced capacity to generate force specifically at the ankle joint post AT rupture suggesting that impairments remain despite a comparable global acceleration performance.