Congenital dislocation of the patella
Objectives- Describe symptoms and physical examination of patients with congenital dislocation of the patella
- Describe treatment approaches for patients with congenital dislocation of the patella
Discussion
Congenital dislocation of the patella is an unusual condition that may occur in isolation or with syndromes such as nail-patella syndrome or Down syndrome. There are two groups of patients, one with a fixed dislocation at birth, and the other in whom the patella is normally located at birth, but progressively subluxates until it is in a fixed dislocated position. Diagnosis is generally not made until after walking age. There is a fixed flexion contracture of the knee, the patella is laterally displaced with genu valgum, and the tibia is externally rotated. The trochlear groove is hypoplastic. The preponderance of reports of natural history seems to be that of increasing disability with age, although some authors report the knee being painless.
Nonoperative treatment is futile. Several operative approaches have been described, which generally include extensive lateral release, advancement of the vastus medialis obliqus, and medial transfer of the patellar tendon insertion. Beals has reported good results from creating a femoral sulcus. The semitendinosus transfer may substitute for the absent medial patellofemoral ligament.
References
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May 16-19, 2012 in Denver, CO
