Osgood-Schlatter’s Disease

Anthony G. Ryan and Peter L. Munk

A 13-year-old boy presented to his family doctor with a history of anterior knee pain. Direct questioning revealed he had recently taken part in a track and field competition. Physical exam revealed focal tenderness over the tibial tuberosity. He had full range of passive motion but a somewhat limited knee extension secondary to the pain. The practitioner sent the boy for a radiograph, which revealed no significant abnormality, but because the boy had ongoing pain, he was referred to an orthopedic surgeon, who requested an MRI.

Figure 9A

Figure 9B

Figure 9C

Osgood-Schlatter disease.

• Normal Variant The normal ossification pattern between 8 and 14 years may simulate a fragmented tuberosity. The patient will not be symptomatic, however.
  
• Osteitis In the appropriate setting, tuberculous osteitis may be considered.

The etiology of Osgood-Schlatter disease remains unclear, although there is consensus that trauma is the underlying cause.

The debate arises in how one describes the actual injury; that is, all the following may be described in the complex of injuries described as Osgood-Schlatter disease: a cartilaginous avulsion fracture of the tibial tuberosity, a tear of the patellar tendon at its tibial insertion, or chronic tendinitis of the patellar tendon with secondary ossification. The features common to all the above involve a tendon abnormality, with or without an attendant osseus component, as evinced by the characteristic findings of persistent ossific fragments within a thickened patellar tendon in the later stages of the disease. This begs the question regarding the existence of an actual fracture at the time of injury or whether it is ossification within a chronic tendinitis.