Of eighty-five consecutive patients, thirteen to twenty years old, with
spastic cerebral palsy involving one or both extremities (thirty-five
patients seen at one institution and fifty, at another), four had
roentgenographic evidence of fragmentation of the distal pole of the
patella. In addition, three other patients with six spastic lower
extremities, four of them with patellar fragmentation, were also included.
In these seven patients, there were nine knees with patellar fragmentation,
twelve knees with patella alta, nine with a flexion contracture, five that
were painful, and four with changes in the tibial tubercle resembling those
found in Osgood-Schlatter disease. Excessive tension in the quadriceps
mechanism, usually in the presence of a flexion contracture, appeared to
cause the lesions. Four of the fragmented patellae healed after hamstring
release and correction of the flexion deformity.