Long-term results of arthroscopic medial reefing for patellar instability.

Background: The purpose of the study was to investigate the long-term outcomes of the all-inside arthroscopic medial reefing (AAMR) procedure for patellar instability and the factors that affect successful outcome.

Methods: In this retrospective study, AAMR with suture was performed in 16 knees of 15 patients who had at least one patellar dislocation and did not experience a decrease in pain and who did not have a major radiological bony abnormality. Preoperatively, Tegner and Lysholm scales were used; for the final evaluation Tegner, Lysholm, Kujala and Knee injury and Osteoarthritis Outcome Score (KOOS) were used.

Results: The average age of the patients at the time of operation was 18 years (range: 11-36 years). The average follow-up time was 118.3 months (range: 85-143 months). Six of the 16 knees (37.5%) exhibited re-dislocation. Preoperatively, the mean Lysholm and Tegner were 66.5 and 4.0, respectively; and postoperatively increased to 89.3 (P = .001) and 4.66, respectively. At the final follow-up, mean Kujala was 89.3 (good), and mean KOOS was 91.4. In all patients with re-dislocation, fewer than four knots were used, and none of the patients with four knots exhibited re-dislocation. Re-dislocations occurred in two, two, one and one patients at two, three, five and eight years, respectively.

Conclusions: The AAMR technique is associated with minimal incisional scarring and an increase in functional scores. It is also associated with a high risk of re-dislocation compared with other methods. If the technique still needs to be used, despite the high re-dislocation rate, at least four knots should be applied.