Biomechanics of the Tibiofemoral and Tibiofibular Joints

The tibiofemoral joint (TFJ) and proximal tibiofibular joint (PTFJ) are imperative to the dissipation of external forces. As such, the biomechanics of the TFJ and PTFJ are important for normal lower limb function both at rest and during locomotion. The TFJ is a complex joint exhibiting 6 degrees of freedom. As a result of its complicated role, multiplanar rotations and translations often occur simultaneously at the joint. Notable biomechanical phenomena that occur at the TFJ include the screw-home mechanism and femoral rollback. These kinematic mechanisms provide increased stability to the joint in extension, as well as deep flexion and improved extensor mechanism function. The TFJ therefore plays an essential role in most activities of daily living.

In contrast to the TFJ, range of motion at the PTFJ is limited, with most movement occurring in transverse plane rotation. Other rotational and translational movements are reported to be negligible (<1°/<1 mm) due to its strong ligamentous support. However, high transmission of fibula-talus force to the PTFJ suggests that the joint is important for the dissipation of external forces.