Kinematic Alterations After Anterior Cruciate Ligament Reconstruction via Transtibial Techniques With Medial Meniscal Repair Versus Partial Medial Meniscectomy

Background: The treatment strategies for meniscal injuries during anterior cruciate ligament (ACL) reconstruction remain a topic of debate. Hypothesis: After ACL reconstruction, knee kinematics would be affected by different medial meniscal treatment (partial medial meniscectomy [PMM] and medial meniscal repair [MMR]). Study Design: Controlled laboratory study. Methods: A total of 161 patients underwent primary single-bundle ACL reconstruction and simultaneous medial meniscal treatment. Of these, 32 patients were eligible to participate in the kinematic assessment at 24.8 ± 1.7 months after surgery. Patients were divided into 2 groups: (1) those who underwent MMR (Group MMR; n = 18) and (2) those who underwent PMM (Group PMM; n = 14). Twenty healthy participants (Group Intact) were recruited who were comparable in age, body mass index, and sex. The kinematic parameters were collected using an optical tracking system during treadmill gait. Range of motion and kinematic parameters at key events during the gait cycle were compared between the 3 groups. The primary outcomes were the differences in adduction/abduction and internal/external rotation. Results: Patients in Group PMM walked with increased adduction as compared with those in Group Intact during the early stance phase ( P = .003; η 2 = 0.172) and midstance phase ( P = .003; η 2 = 0.167). In terms of internal/external rotation, patients in Group PMM walked with significantly larger tibial external rotation when compared with Group MMR by approximately 3.4° to 3.7° (loading response: P = .026, η 2 = 0.090; midstance: P = .035, η 2 = 0.093) and Group Intact ( P = .028; η 2 = 0.095) in the early stance phase. In addition, there was significantly increased anterior tibial translation in Groups MMR and PMM compared with Group Intact. Conclusion: ACL reconstruction (via transtibial technique) with concurrent PMM demonstrated larger adduction and external tibial rotation at 24 months of follow-up during level walking. Clinical Relevance: Patients undergoing different medial meniscal treatment strategies in the presence of ACL reconstruction showed distinct knee kinematics. These results suggest that MMR is strongly recommended during ACL reconstructive surgery to reduce the abnormal kinematics close to that of the ACL-intact condition.