Biomechanical comparison of rotational activities between anterior cruciate ligament- and posterior cruciate ligament-reconstructed patients.

Purpose: The purpose of this study was to compare the early functional recovery using biomechanical properties between anterior cruciate ligament (ACL)- and posterior cruciate ligament (PCL)-reconstructed patients and to determine the biomechanical deficit of PCL-reconstructed patients compared to ACL-reconstructed patients.

Methods: A motion analysis system was used to measure and calculate kinematic and kinetic data for 10 patients who underwent PCL-reconstructed patients [experimental group (group 1)], 10 ACL-reconstructed patients (group 2), and 10 healthy subjects (group 3) during 45°, 90°, 135°, and 180° cutting and turn running tasks. Groups 1 and 2 were assessed at 3 (return to daily activity) and 6 months (return to light sports) postoperatively.

Results: At 3 months postoperatively, compared to groups 2 and 3, group 1 showed a decrease in knee flexion angle, extension moment, valgus moment, external rotational moment, ground reaction force, and increased hamstring-quadriceps ratio. At 6 months postoperatively, results from group 1 resembled those of groups 2 and 3 over time.

Conclusions: Patients who underwent PCL reconstruction showed some biomechanical deficits in performance of activities requiring rotation, compared to those who underwent ACL reconstruction. Therefore, the modification of a rehabilitation programme for patients who underwent PCL reconstruction would be necessary for improvement of the biomechanical properties during performance of dynamic activities.

Level Of Evidence: Case-control study, Level III.