Effect of posterior cruciate ligament rupture on the radial displacement of lateral meniscus

- Effect of posterior cruciate ligament rupture on lateral meniscus radial displacement is unclear.
- Partial posterior cruciate ligament rupture increases lateral meniscus radial displacement.
- Complete posterior cruciate ligament rupture increases lateral meniscus radial displacement.

BackgroundThe relationship between lateral meniscus tear and posterior cruciate ligament injury is not well understood. The present study aims to investigate and assess the effect of posterior cruciate ligament rupture on lateral meniscus radial displacement at different flexion angles under static loading conditions.MethodsTwelve fresh human cadaveric knee specimens were divided into four groups such as posterior cruciate ligament intact, anterolateral band rupture, posteromedial band rupture and posterior cruciate ligament complete rupture groups, according to the purpose and order of testing. Radial displacement of lateral meniscus was measured under different loads (200-1000 N) at 0°, 30°, 60°, and 90° of knee flexion.FindingsCompared with posterior cruciate ligament intact group, the displacement values of lateral meniscus in anterolateral band rupture group increased at 0° flexion with 600 N, 800 N, and 1000 N and at 30°, 60° and 90° flexion under all loading conditions. Posteromedial band rupture group exhibited higher displacement at 0° flexion under all loading conditions, at 30° and 60° flexion with 600, 800 N and 1000 N, and at 90° flexion with 400 N, 600 N, 800 N, and 1000 N than the posterior cruciate ligament intact group. The posterior cruciate ligament complete rupture group had a higher displacement value of lateral medial meniscus at 0°, 30°, 60° and 90° flexion under all loading conditions, as compared to the posterior cruciate ligament intact group.InterpretationThe study concludes that partial and complete rupture of the posterior cruciate ligament can trigger the increase of radial displacement on lateral meniscus.