Treatment of Acute Traumatic Patella Dislocation

ABSTRACT

PURPOSE: To analyze clinical results of the cases diagnosed and treated as acute patella dislocation. MATERIALS AND METHODS: Thirteen cases diagnosed as acute patella dislocation between March 2000 and May 2006, were enrolled for this study. The mean follow-up period was 28 months. Preoperatively plain radiographs and MRIs were taken, and operative treatment was performed in 11 cases with osteochondral fragments or patella malalignment after reduction. Clinical results were assessed by the range of motion and the Lysholm score. For radiologic assessment, patella tilt by lateral patellofemoral angle and patella subluxation by congruence angle were observed. RESULTS: In all cases(100%), bone contusion was observed on MRIs. Osteochodral injury was found in six cases (46.1%). The postoperative mean range of motion was from 0 degree to 130 degrees, and the mean Lysholm score was 86 points. The congruence angle was recovered to -10.9 degrees from 1.7 degrees in 12 cases except one case. No case presented lateral patella tilt when the lateral patellofemoral angle was measured. CONCLUSION: Bone contusion on MRIs was helpful in diagnosing acute traumatic patella dislocation. Operative treatment is considered necessary for the cases with remained patellofemoral malalignment or osteochondral fragments after reduction.