Review Question - QID 214014

This patient’s imaging is consistent with a stable osteochondritis dissecans lesion of the lateral femoral condyle. Initial treatment with restrictive weight bearing is indicated in stable lesions in children with open physis.

OCD lesions are found most commonly in the posterolateral aspect of the medial femoral condyle. However, this patient’s MRI demonstrates an osteochondritis dissecans lesion on the lateral femoral condyle. Importantly, the cartilage appears to be intact and the lesion is not displaced. Without previous treatment, initial nonoperative management with restricted weight bearing is indicated. This initial conservative treatment modality results in 50-75% of these OCD lesions heal without fragmentation. The presence of open distal femoral physes has been shown to be the best predictor of successful non-operative management. If this patient continues to be symptomatic after failing conservative treatment, then subchondral drilling would be the next step in surgical management. Unstable osteochondritis dissecans (OCD-type II and III according to the ICRS classification) often require surgical intervention.

Carey et al. review their preferred treatment algorithm for OCD lesions of the knee is based on skeletal maturity, lesion stability, and lesion salvageability. They report that for unstable yet salvageable OCD lesions, fixation with bone grafting is preferred. They conclude that unstable and unsalvageable OCD lesions are most commonly managed with autologous chondrocyte implantation with bone grafting.

Jones et al. review the etiology, clinical presentation and prognosis of OCD lesions in the knee. They present an algorithm for treatment, which aims to promote healing of native hyaline cartilage and to ensure joint congruity. They conclude that although there is no clear consensus as to the best treatment of OCD, every attempt should be made to retain the osteochondral fragment when possible.

Schulz et al. review the current concepts in the diagnosis and management of juvenile OCD lesions of the knee. They report that an underlying vascular insult, resulting in separation of the progeny lesion from the parent subchondral bone, is a suspected cause but remains unproven. They state that nonsurgical treatment with activity modification remains an option for stable lesions in young patients. They conclude that unstable and displaced lesions remain a difficult treatment challenge.

Figure A is the coronal MRI image demonstrating an OCD lesion of the lateral femoral condyle. Figure B is the corresponding sagittal MRI image of the stable OCD lesion of the lateral femoral condyle. Illustration A is the coronal MRI image demonstrating an unstable OCD lesion of the medial femoral condyle. Illustration B is the Clanton classification for OCD lesions.

Incorrect Answers:
Answer 1: Conservative management would include a period of non-weight bearing or activity modification. Aggressive physical therapy would likely exacerbate the patient’s symptoms and is not indicated.
Answer 2: Fragment removal, with or without grafting, is not indicated for this stable lesion in a skeletally immature patient.
Answer 3: Arthroscopic drilling may be indicated in this patient if he fails a trial of nonoperative management.
Answer 5: Osteochondral allograft transplantation may be reserved for unstable and unsalvageable OCD lesions.