Medial retinaculum reefing for the treatment for patellar instability

Medial structures repair is a well-established approach in the treatment for patellar instability. However, the literature is confusing concerning the indications for surgery, the different surgical techniques and outcomes. The goal of this systematic review was to clarify the indications for medial structures repair and to analyse the results of both arthroscopic and open techniques.

A comprehensive literature review was performed using the keywords 'patellar instability', 'medial capsule reefing' and 'medial capsule plication' with no limit regarding the year of publication. All the selected articles in Anglo-Saxon language were evaluated with the Coleman methodology score.

Seventeen full-text articles were evaluated. Initial cohort included 617 patients. About 569 patients were reviewed at an average FU of 54.6 months (range 2-165 months) after medial structures repair. Average age at the time of surgery was 21.2 years (range 9-65 years). The indications for surgery included both patellar subluxation and dislocation (acute or chronic). Average Kujala score increased from 55 to 84 at the last FU, and in the same way average Lysholm score increased from 41.2 to 80.5, whereas average Tegner score increased from 3 to 5.3 and IKDC score from 47.8 to 75.1. Re-dislocation rate among the series was 6.1%. Average Coleman methodology score was 61.6 (range 17-92).

From this review, it emerges that medial capsule reefing is a reliable option in the treatment for patellar instability. It can be proposed with good expectations, since the outcomes are positive and stable even at longer FU and complications rates are low. Re-dislocation rate is variable and can occur in up to one-third of patients. However, most of the available studies are case series, and comparison of the series is hard since they widely differ in inclusion criteria and indications, surgical technique and additional procedures, and outcome measures.