Medial patellar retinaculum plasty versus medial capsule reefing for patellar subluxation in adult.

Objective: The purpose of this study was to evaluate the clinical and functional results of surgical treatment for patellar subluxation.

Methods: A retrospective study was undertaken between October 2004 and April 2009 of 78 cases of patellar subluxation: 40 cases with medial capsule reefing, of which 15 cases had the combination of lateral retinacular release (Group A); and 38 cases with medial patellar retinaculum plasty, of which 12 cases had the combination of lateral retinacular release (Group B). All patients had CT scans available for reviewing congruence angle (CA) with knee flexion at 30 degrees. In addition, knee function was evaluated using the Kujala score and subjective questionnaires.

Results: Patients were followed up for a mean 60 months (33-87 months). The Kujala score improved significantly from 78.3 ± 1.0 to 88.3 ± 1.6 in Group A and from 77.8 ± 0.9 to 91.2 ± 1.7 in Group B (P < 0.05). Postoperatively, the CA on CT scan had a statistical difference between the two groups (P < 0.05). The subjective questionnaire revealed a significant difference (P < 0.05), including 12 excellent, 20 good and eight fair in Group A, and 25 excellent, and 13 good in Group B.

Conclusion: The medial retinaculum plasty was better than medial capsule reefing in improving the subjective effects and decreasing the patellar subluxation rate.