Background: Return to play after medial patellofemoral ligament reconstruction (MPFLR) or medial patellofemoral ligament reconstruction with tibial tubercle osteotomy (MPFLR/TTO) is traditionally guided by time from surgery, knee range of motion, and strength. It is unclear how dynamics such as sport played, psychological factors, and pre-operative risk factors may affect an athlete’s ability to return to sport. This study focuses on the role of these factors in changing how quickly/effectively athletes can resume sports participation after MPFLR or MPFLR/TTO.

Methods: A literature search was conducted, according to PRISMA guidelines, on PubMed, EMBASE, CINAHL, Web of Science, Scopus, and Cochrane Library. Studies were included if patients underwent MPFLR or MPFLR/TTO for patellar instability, return to play following surgery was measured, and if a factor that may change ability/time to return to sport was mentioned. Search terms included medial patellofemoral ligament, tibial tubercle osteotomy, tibial tubercle transfer, return to play, and return to sport. Data on return to sport, subjective knee scores, and factors affecting return to play was collected. Results: 452 studies were screened and 18 were included in this review. 83.1% (729/877) successfully returned to sport at a mean of 8.46 months post-operatively. Fear of re-injury or perceived non-improvement in their knee function was the reasoning of 27.2% (78/287) of patients that did not return to sport or returned at a lower level. Volleyball/handball, skiing, and soccer had a large decrease in participation following surgery (61.1%, 40%, and 28.6%, respectively). A positive apprehension test post-operatively was associated with significantly lower return to sport rate (69.6% vs 95.4%, p= 0.03). Pre-operative trochlear dysplasia was associated with significantly lower post-operative subjective knee scores in several studies (kujala [p= 0.02, 0.0001] and lysholm [p= 0.001]). Conclusions: Fear of re-injury, type of sport played, post-operative positive apprehension test, and trochlear dysplasia have been documented as influential factors in return to sport following patellar stabilization surgery. The breadth of literature on this subject is poor and primarily made up of observational studies, future studies on the dynamics effecting return to sport following these procedures is crucial so physicians can best advise patients during their rehabilitation.