Tibial meniscal dynamics using three-dimensional reconstruction of magnetic resonance images.

The human knee joint represents a complex biomechanical system of which the menisci are an integral component. At present, little data exists describing the meniscal kinematics of the intact knee. Accordingly, a three-dimensional reconstruction magnetic resonance image model was used to explore this issue. Five fresh cadaveric knees were examined by magnetic resonance imaging throughout a full range of motion at 10 degrees intervals. Computer three-dimensional images of the menisci were generated and evaluated for anteroposterior excursion and deformation. During flexion, the posterior excursion of the medial meniscus was 5.1 mm, while that of the lateral meniscus was 11.2 mm. The anterior horn segments were shown to be more mobile than the posterior horn segments bilaterally. Prior limitations of meniscal kinematic assessment may be overcome with advanced imaging techniques such as magnetic resonance imaging and three-dimensional reconstruction. The menisci are highly mobile and easily deformed structures within the intact, cadaveric knee. This imaging technique may prove useful in the elucidation of meniscal dynamics. In the future, similar techniques may be applied clinically to aid in the diagnosis of joint dysfunction.