Mini-open medial reefing and arthroscopic lateral release for the treatment of recurrent patellar dislocation: a medium-term follow-up.

BACKGROUND: Although recurrent patellar dislocations are not uncommon, their pathophysiology and treatment are controversial.

HYPOTHESIS: Stabilization of recurrent patellar dislocations can be successfully managed with a mini-open approach.

STUDY DESIGN: Case series; Level of evidence, 4.

METHODS: Twenty-two patients (23 knees) underwent a mini-open medial reefing and arthroscopic lateral release for the treatment of recurrent patellar dislocations with an average follow-up of 4.4 years (range, 1.4-14 years). The average age at the first dislocation was 15 years (range, 5-26 years), and the average age at surgery was 23 years (range, 12-65 years).

RESULTS: There was 1 postoperative dislocation (4%) and 1 recurrent subluxation (4%). The average Kujala knee score was 88.2 +/- 13.5, with overall good scores in each category. The lowest scores involved squatting (5.7), abnormal painful kneecap movements (subluxations) (7.1), and jumping (7.9). Overall, there was a statistically significant improvement in the Tegner score from 3.7 +/- 1.8 before surgery to 6.9 +/- 2.0 after surgery (P < .001). Six knees (26%) were rated subjectively as excellent, 15 (65%) as good, 2 (9%) as fair, and 0 (0%) as poor. All 22 patients (100%) stated that the procedure was worthwhile. Radiographically, there was a statistically significant improvement in the congruence angle (normal, -8.0 degrees +/- 6.0 degrees) from 15.7 degrees +/- 12.6 degrees (range, 0.0 degrees to +44.0 degrees) before surgery to -11.5 degrees +/- 8.7 degrees (range, -20.0 degrees to +10.0 degrees) after surgery (P < .001) and in the lateral patellofemoral angle (normal, >0 degrees) from -0.2 degrees +/- 6.4 degrees (range, -10 degrees to +8 degrees) before surgery to 7.9 degrees +/- 2.6 degrees (range, 0.0 degrees to +11.0 degrees) after surgery (P < .001).

CONCLUSION: Our mini-open technique provides anatomical restoration with limited morbidity and cosmetically appealing results. Furthermore, our redislocation rates compare favorably with traditional, more extensile open approaches.