Adding Lateral Retinacular Release to Medial Patellofemoral Ligament Reconstruction Fails to Demonstrate Clinical Benefit Compared With Isolated Medial Patellofemoral Ligament Reconstruction.

PURPOSE: To compare functional outcomes and failure rates between medial patellofemoral ligament (MPFL) reconstructions with and without lateral retinacular release (LRR) at minimum 1-year follow up.

METHODS: A retrospective review identified consecutive patients from 2013 to 2019 at a single center who met all of the following inclusion criteria: at least 1 confirmed patellar dislocation, patellar tilt (evidenced by tight retinaculum on operative examination or patellar tilt on radiographs), underwent either MPFL reconstruction alone or combined with LRR, had available preoperative documentation and imaging, and were at least 1 year out of surgery. Patients were excluded if they had previous surgery to the ipsilateral limb or had any concomitant procedure performed. Demographics and preoperative imaging were evaluated. Failure rates and functional outcome scores were obtained including Kujala, Patient-Reported Outcomes Measurement Information System, International Knee Documentation Committee, Single Assessment Numeric Evaluation, and Knee injury and Osteoarthritis Outcome Scores. Clinical failure was defined as revision MPFL reconstruction on the affected knee or at least 1 instance of postoperative patellar dislocation.

RESULTS: A total of 18 patients underwent isolated MPFL reconstruction (mean follow-up = 29.3 ± 8.3 months, range = 15.1-42.8 months), and 31 underwent MPFL reconstruction combined with LRR (mean follow up = 36.0 ± 11.3 months, range = 14.0-51.9 months). At final follow-up, there were no statistical differences between the isolated MPFL and MPFL combined with LRR cohorts for any of the functional outcome scores ( P > .05 for all). At the time of final follow-up, no patients who underwent isolated MPFL and 19.3% (n = 6) or patients undergoing MPFL combined with LRR experienced clinical failure ( P  = .073), as defined by subsequent patellar dislocation or revision MPFL reconstruction. Of these, 2 patients underwent revision MPFL reconstructions with distal tubercle transfer for borderline abnormal TT:TG (i.e., >15 mm).

CONCLUSIONS: MPFL reconstruction surgery combined with LRR failed to demonstrate significantly different functional outcome scores and failure rates compared with isolated MPFL reconstruction at minimum 1-year follow up. In addition, there were no differences in rates of achieving MCID between both groups.

LEVEL OF EVIDENCE: Level III, retrospective cohort study.