Effect of deep medial collateral ligament release during high knee flexion movements

Purpose The medial preserving gap technique has recently been used in total knee arthroplasty. Generally, the deep medial collateral ligament (DMCL) is released using this technique. However, the effect of DMCL release on the kinematics and length of the ligaments remains unknown. This study aimed to clarify how DMCL release affects the kinematics and length change of the ligaments during high knee flexion movements. Methods Three cadaveric knees were examined using a computed tomography-based navigation system. The following parameters were evaluated: femoral rotation and varus-valgus angle relative to the tibia; anteroposterior translation of the sulcus distal to the medial epicondyle (medial side) and tip of the lateral epicondyle of the femur (lateral side); mediolateral translation of the medial and lateral sides of the plane perpendicular to the tibial mechanical axis; and kinematic pathways during non-weight-bearing knee flexion, cross-legged motion, and sideways motion. Results There were no significant differences in the kinematics and length change of the ligaments during all movements after DMCL release compared with that before DMCL release. Conclusion DMCL release did not affect the kinematics and length change of the ligaments.