Long-Term Outcome After Operative Treatment of Traumatic Patellar Dislocation in Adolescents

OBJECTIVES:Retrospective evaluation of the long-term outcomes after surgical treatment of traumatic patellar dislocations in adolescents and identification of possible predictive factors of poor outcomes. DESIGN:Retrospective clinical study. SETTING:University Clinic, Level I Trauma Center. PATIENTS:All 33 adolescents, with a mean age of 14.8 years, who were treated surgically after traumatic patellar dislocation between 1994 and 2006, were involved in this study. INTERVENTION:Mini-open medial reefing and arthroscopic lateral release. MAIN OUTCOME MEASUREMENTS:The clinical outcome was evaluated with the visual analogue scale, the Lysholm score, the Kujala score, and the Tegner activity level scale. On preoperative radiographs and magnetic resonance imaging scans, trochlear dysplasia and patella alta were assessed. The variables analyzed were sex, associated osteochondral injuries, the number of redislocations before surgery, and the number of redislocations after surgery. RESULTS:At the mean follow-up of 9.8 years, the mean Lysholm score was 82.6, the mean Kujala score was 84.4, the mean Tegner activity level was 4.8, and the mean visual analogue scale was 0.2. We found no significant differences in the subgroups regarding functional outcomes. Fifteen patients with patella alta and 4 patients with trochlear dysplasia were assessed radiologically. Redislocations after surgery were observed in 4 patients, 2 of them were female patients who exhibited quadriceps angles requiring tibial tubercle osteotomy to be performed after maturation. CONCLUSIONS:The techniques of mini-open medial reefing and lateral release demonstrate a good functional long-term outcome and effectively prevent recurrent instability. The major predictive factor for poor outcomes and redislocations is an inadequately addressed pathology. LEVEL OF EVIDENCE:Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.