Return-to-Sport Assessment After Medial Patellofemoral Ligament Reconstruction Shows Substantial Variability in Objective Criteria.

Purpose: To evaluate objective return-to-sport (RTS) outcomes and limb symmetry index (LSI) data after primary medial patellofemoral ligament reconstruction (MPFLR) in patients with patellar instability. Methods: A systematic search of Scopus, PubMed, CINAHL, and Embase (2000-2024) identified studies reporting RTS outcomes and LSI-based performance testing in patients undergoing primary MPFLR. Clinical and observational studies reporting objective metrics such as isokinetic strength and hop testing were included. Results: Six studies including 243 patients (64% women, mean age 19.4 years) undergoing primary MPFLR were included. Several studies included patients undergoing concomitant bone procedures (41%), such as tibial tubercle osteotomy or trochleoplasty. Objective RTS testing commonly included isokinetic strength (4 studies), hop testing (3 studies), and Y-Balance testing (2 studies). Follow-up testing ranged from 6 to 8 months postoperatively. Reported LSI values ranged from 83% to 94% for isokinetic flexion, 70% to 96% for isokinetic extension, 85% to 93% for single hop, and 90% to 97% for triple hop. Time to RTS ranged from 6.1 to 8.1 months across studies, with RTS rates from 85% to 100%. However, only 14% to 40% of patients met all study-specific RTS criteria when reported. Testing protocols and thresholds varied across studies, contributing to heterogeneity in outcomes. Conclusions: Few studies reporting RTS outcomes after MPFLR incorporate LSI measures as part of RTS assessment, and only a minority define explicit RTS criteria based on objective testing. Among studies that reported LSI, quadriceps strength frequently remained below 90% LSI at the time of RTS. Despite high reported RTS rates, substantial variability exists in RTS assessment after MPFLR. Level of Evidence: Level IV, systematic review of Level III to IV studies.