Central dislocations of the patella.

The rare traumatic condition of intra-articular dislocation of the patella in a 12-year-old boy is described, suffered in a fall, when he landed in a hole with his knee bent. Closed reduction by manipulation under general anesthesia failed because the upper pole of the patella was locked deeply in te intercondylar space. Operative reduction using a parapatellar incision in which the patella was levered into position without opening the capsule was followed by functional recovery.