Combined Effect of Tibiofemoral Alignment and Meniscectomy on the Contact Stresses at the Knee: A FEA Investigation

Surgical removal of meniscal tissue alters the kinematics and load distribution of the knee and decreases the contact area causing greater magnitude of compressive stress and shear stress. These changes may result in damage to the knee cartilage and lead to subsequent osteoarthritis (OA) (1). Allen et al. (2) found a significant increase in knee OA after meniscectomy with pre-existing abnormal frontal plane tibiofemoral alignment. Tibiofemoral alignment affects the varus/valgus moment during ambulation and during single-leg stance, Fig. 1A. The varus moment, or adduction moment, is the primary factor in the distribution of the force to the medial compartment of the knee joint during normal gait (4). Previous finite element analysis (FEA) studies investigating partial and total meniscectomies applied only axial loads and do not take into account the varus moment that occurs during single-leg support (4, 5). The present 3-D FEA investigation utilizes subject specific loading conditions (including the varus knee moment) to study the combined effect of tibiofemoral knee alignment and partial and total meniscectomies on the stresses at the knee cartilage.