Individual and Combined Effects of Anterior Cruciate Ligament and Lateral Meniscus Injuries and Surgical Interventions on Tibiofemoral Peak Pressure Magnitude Vary by Flexion Angle.
PURPOSE: To quantify changes in peak tibiofemoral pressure magnitude and location following anterior cruciate ligament (ACL) and meniscus injuries and surgical interventions after cyclic motion. METHODS: Six matched pairs of cadaveric knees underwent ACL or lateral meniscus injury and surgical intervention; specimens later underwent the other injury and surgical intervention. A servohydraulic testing system flexed and extended specimens 100 times before and following each intervention. Pressure magnitudes and locations were measured via submeniscal sensors on the medial and lateral tibial plateaus under 4 conditions (each at 0°, 15°, 30°, 45°, and 60° of knee flexion): native anatomy, first injury (InjPost1), first surgical intervention (SurgPost1), and second surgical intervention (SurgPost2). Linear mixed models compared interactions between group, side, and condition through SurgPost1 and interactions between side and condition for native and SurgPost2 for the magnitude and location of peak pressures. RESULTS: Peak pressure was greater at 0°, 15°, and 30° in the medial compartment than the lateral compartment, regardless of injury condition. For the ACL group, at 0°, peak pressure in the lateral compartment was more posterior than the medial compartment, and at 15°, the meniscus group displayed more posterior peak pressure in the medial compartment than the lateral compartment. Greater anterior peak pressure was observed at 15° in SurgPost1 than native anatomy. Peak pressure was greater in SurgPost2 than native in the lateral compartment at 30°. For native and SurgPost2, peak pressure was greater in the medial compartment than the lateral compartment at 15° and greater in the lateral compartment than the medial compartment at 60°. CONCLUSIONS: ACL and meniscus injuries and surgical interventions result in similar anterior peak pressure translation. Sustaining both injuries and surgical interventions increases peak pressure magnitude. CLINICAL RELEVANCE: Understanding how peak tibiofemoral contact pressures change in magnitude and location following an ACL or lateral meniscus injury and treatment may help guide treatment decisions and rehabilitation strategies that best prevent knee joint degeneration.
