OBJECTIVETo compare therapeutic effects between arthroscopic medial retinaculum plication and plaster external fixation for the treatment of acute patellar dislocation.

METHODSFrom February 2006 to October 2012,29 patients with acute patellar dislocation were divided into two groups: operation group and non-operation group. The patellar dislocation duration was 2 weeks. In operation group, there were 7 males and 10 females, with an average age of (16.2 ± 6.2) years old, and the patients were treated with arthroscopic medial retinaculum plication. In non-operation group, there were 5 males and 7 females,with an average age of (16.3 ± 5.0) years old,and the patients were treated with plaster external fixation. The Kujala scores, patellar tilt angle measured on CT film, apprehension test and recurrence rate of patellar instability were observed before and 1 year after treatment.

RESULTSIn operation group, the pre-treatment and post-treatment patellar tilt angles had no statistical difference, but the post-treatment Kujala score was lower than that of pre-treatment; while in non-operation group, the post-treatment patellar tilt angle was larger than that of pre-treatment, and the post-treatment Kujala score was lower than that of pre-treatment. At 1 year after treatment, the patellar tilt angle (21.2 ± 5.3) of patients in non-operation group was larger than (13.5 ± 3.5) of operation group, and the Kujala score 73.3 ± 10.5 of patient in non-operation group was lower than 84.1 ± 5.6 of operation group.

CONCLUSIONDuring 1 year after operation, arthroscopic medical retinaculum plication is a more effective treatment for acute patellar dislocation compared with plaster external fixation.