Patellofemoral Joint Instability (Journal of Orthopaedics and Trauma)


The patellofemoral joint remains the enigma of orthopedics and sports medicine. Patellar dislocation is a common problem in the younger and athletic population and it is more disabling than cruciate ligament injuries. The pathology is often multifactorial and complex with no one factor being the sole defining etiology. The current management of patella dislocation has been linked with poor patient satisfaction possibly due to a prolonged period of conservative treatment and the general tendency to delay surgical intervention. This review will address the main abnormal anatomical factors contributing to patellar instability, their clinical and radiological diagnoses, and the role of various surgical interventions, including the medial patellofemoral ligament reconstruction in stabilizing the patella.

Patellofemoral joint instability (PFJI) covers a broad spectrum of abnormalities ranging from frank acute patellar dislocations to subtle maltracking. The incidence of acute lateral patella dislocations is 2–3% of all knee injuries. Acute patellar dislocation could be the tip of the iceberg and the beginning of multiple subsequent recurrent patellar dislocations. It is evident that there is a 17–49% risk of redislocation following first-time acute patellar dislocation. It is particularly higher in patients below 20 years of age. The risk increases to 44–71% following a second-time dislocation. Acute dislocation has been associated with osteochondral lesions in 49% of PFJI patients, and with medial patellofemoral ligament (MPFL) disruption in over 90– 100% of patients. There is high patient dissatisfaction after conservative treatment, nearly two-thirds (58%) reporting limitations in strenuous activities even six months after treatment and 55% of these patients fail to return to sporting activities. Chronic PFJI and recurrent dislocation may eventually lead to progressive cartilage damage and severe osteoarthritis (OA) if not treated adequately. The risk of OA is 35% after conservative treatment. Therefore, it is crucial to adopt a new strategy in dealing with this relatively common condition that mainly affects younger and athletic populations. Our understanding of PFJ biomechanics and pathogenesis has evolved over the last two decades, which would hopefully translate to better patient outcomes. This review article will address some of the challenges that are faced in quantifying PFJI and the surgical and nonsurgical options that are currently available to us.

Thanks & Regards,


Managing Editor

Journal of Orthopaedics and Trauma