Surgical treatment of congenital dislocation of the patella

Eleven patients with 17 involved knees were surgically treated for congenit al dislocation of the patella between 1978 and 1993. Ten patients with 13 i nvolved knees followed up for a minimum of 2 years postoperatively composed the study group. Six patients had both involved knees operatively treated. Ln four patients, congenital dislocation of the patella was associated wit h a recognizable syndrome. All patients had fixed, painful lateral dislocat ion of the patella that could not be reduced. The average age at presentati on was 7 years and 9 months (range, 2 months to 15 years). All patients und erwent an extensive procedure including lateral release and advancement of the vastus medialis obliquus. Skeletally immature children underwent medial transfer of the entire patellar tendon. Skeletally mature patients underwe nt medial transfer of the tibial tubercle. Ten patients with 13 involved kn ees were followed up for greater than or equal to 2 years. Mean follow-up w its 5.1 years (range, 1-17.5). At last follow-up, all patients reported a m arked increase in activity tolerance and relief of pain. Average extension lag improved from 15 degrees before to 2 degrees after surgery. One superfi cial wound infection occurred; no patient developed a deep infection. One p eroneal neurapraxia occurred but resolved with observation. Redislocation o f the patella occurred in the immediate postoperative period in one patient . Operative treatment of congenital dislocation of the patella can predicta bly improve knee function when all aspects of the complex pathologic anatom y are addressed.