Adapting Cartilage Restoration to the Patellofemoral Compartment

Treating symptomatic chondral and osteochondral defects of the patellofemoral joint poses a challenge to surgeons due to the limited healing potential of articular cartilage as well as complex surface morphology of the patella and trochlea. In addition, the patellofemoral joint is further complicated by high compressive and shear stresses combined with variable alignment and patella tracking between patients. Initial management for most lesions consists of nonoperative measures, but surgery should be considered for symptomatic patients who fail nonoperative treatment. Surgical procedures can be divided into marrow stimulation (microfracture and drilling), cell-based (autologous chondrocyte implantation and particulated juvenile articular cartilage), and osteochondral (osteochondral allograft transplantation and osteochondral autograft transfer). In addition, fixation of chondral or osteochondral fragments can be considered following traumatic injuries and dislocations. Goals of surgical management include recreating the articular surface architecture and improving the biomechanical environment through addressing associated conditions such as malalignment and patellar instability. Historically, outcomes following patellofemoral cartilage restoration have generally been inferior to tibiofemoral outcomes, but newer studies have demonstrated improved results that rival those of the tibiofemoral compartment.