Quadriceps Tendon Lengthening for Obligatory (Habitual) Patellar Dislocation in Flexion.

Obligatory patella dislocation in flexion is an uncommon form of patellar instability, where the patella is located in extension and dislocates with every episode of knee flexion. This results in dramatically altered patellofemoral kinematics and can be extremely debilitating due to extensor strength deficits and lack of knee confidence in flexion. Concomitant pathology, which is often seen, includes a tight lateral retinaculum and a shortened extensor mechanism. Lengthening the extensor mechanism is a critical part of successful patellar stabilization, and has not been well-reported. Herein, we present a technique of quadriceps lengthening for the treatment of obligatory patellar dislocation.

Return to Play after Patellar Stabilization.

PURPOSE OF REVIEW: The purpose of this review is to evaluate the existing literature regarding return to play (RTP) and return to prior performance (RPP) following patellar stabilization surgery. It will also discuss suggested guidelines regarding RTP, and finally, to encourage future patellofemoral instability research to report and publish results of RTP rates using standardized RTP guidelines. RECENT FINDINGS: There is a lack of validation and universal adoption of standardized RTP guidelines. This has led to a dearth of high-quality studies on RTP and RPP after patellar stabilization. The best available studies to date would suggest high RTP rates (84%-100%), average RPP rates (33%-77%), and a highly variable timeframe for return (3-12 months). Patellofemoral instability can be a persistent and challenging problem, particularly in the young and active population for which it most often occurs. Much of the previous studies on patellofemoral instability evaluated success and failure as prevention of recurrent dislocation. However, prevention of recurrence alone may not be enough for many patients. The best available data on RTP and RPP following patellofemoral instability is based on lower quality of evidence studies, expert opinion, and published societal guidelines. Future research on this topic should include clinical validation of the International Society of Arthroscopy, Knee Surgery, and Orthopaedic Sports Medicine (ISAKOS) RTP guidelines and reporting of outcomes based on these guidelines in patellofemoral instability publications.