Multiple osteochondroses of bilateral knee joints: a case report.

Knee injuries in young athletes include not only the typical adult bone injuries, ligament and cartilage, but also the growth plate lesions. Osteochondroses are idiopathic, self-limited disturbance of enchondral ossification in which a rapid growth spurt is present. The patella could be affected by two different kinds of osteochondroses: Kohler syndrome and Sinding-Larsen-Johansson. Here we are reporting the first case of simultaneous location of osteochondroses of the two ossification centers of both patella. A 9-year-old boy, competitive skater, presented a history of anterior knee pain involving both knees. Standard X-rays, axial patellar view, MRI and arthro-MR were performed. In order to follow the natural history of the pathology and the evolution of the healing, examinations at 2 years were repeated. We proposed the young skater a medical and a physiotherapeutic treatment based on unloading, isometric exercises, NSAID. As the symptoms improve a gradual return to competitive sports activity was allowed. The case mentioned above can be considered an atypical case because the patient suffered for a bilateral knee osteochondroses, involving simultaneously the primary ossification centre (Kohler syndrome) and the secondary ossification centre (Larsen syndrome) of the patella.