Osteochondritis Dissecans in the Skeletally Immature Knee.

Osteochondritis dissecans of the knee, which results in knee symptoms and activity-related pain, is a condition that commonly affects young individuals. The etiology of osteochondritis dissecans remains unclear; however, genetic and endocrine factors, ischemia, inflammation, repetitive microtrauma, and spontaneous osteonecrosis have been suggested as causes of osteochondritis dissecans. Skeletally immature patients with a stable osteochondritis dissecans lesion typically have minimal clinical symptoms and, if treated nonsurgically, experience a high rate of healing. Surgical treatment should be considered for pediatric patients with a stable lesion that does not heal and pediatric patients who have an unstable lesion with articular cartilage defects. Surgical treatment also should be considered for patients who have nearly closed or closed physes, regardless of age. Skeletally immature patients with a stable lesion can be treated via subchondral bone drilling. Advanced lesions that are salvageable may require management via more complex procedures, including fixation with or without bone grafting and cartilage reconstruction procedures, to restore the osteochondral defect.