Three osteochondritis dissecans lesions in one knee: a case report.

BACKGROUND: Osteochondritis dissecans (OCD) has been defined as a localized process in which a focus of subchondral bone and adjacent articular cartilage separates from the surrounding bone. With the knee being the most common location for OCD development and the propensity for this lesion to be found in those who participate in sports, a repetitive microtrauma hypothesis for its cause has gained favor. However, the cause of OCD remains controversial, as does the most appropriate treatment for the varying degrees of OCD lesions. CASE DESCRIPTION: We present a unique case of three OCD lesions in one knee. The patient was a young, athletic boy who developed three separate OCD lesions in his right knee over the course of 4 years. Temporally, the OCD lesions developed first in the lateral femoral condyle, then in the medial femoral condyle, and finally in the trochlea. LITERATURE REVIEW: Our literature review yielded a few reports of bicondylar OCD lesions. We identified no previous reports of three separate OCD lesions found in a single joint. PURPOSES AND CLINICAL RELEVANCE: This report illustrates how a uniquely affected knee with three OCD lesions was treated in three different ways with resolution of symptoms. Each of the OCD lesions was evaluated individually and treatment for each based on the severity of the lesion from the physical examination, imaging studies, and arthroscopic findings.