Review Question - QID 8773

Marked sclerosis on plain radiograph confers a poor prognosis with nonoperative management of osteochondritis dissecans (OCD) lesions. Skeletal immaturity, classic location of the lesion at the lateral aspect of the medial femoral condyle, lesion size < 2cm and stable appearance on MRI all indicate a good prognosis with nonoperative management.

OCD lesions are most common among patients aged 10-15 years. Etiology is unclear but likely multifactorial with hereditary, vascular and genetic factors all contributing. MRI is the imaging study of choice to determine lesion stability. Nonoperative management is recommended in skeletally immature patients with stable lesions, consisting of activity modification and limited weight bearing. The goal of nonoperative management is to promote healing in situ and prevent lesion displacement.

Carey et al detailed their preferred treatment algorithm for OCD lesions in athletes. Patients with asymptomatic lesions discovered incidentally may continue to play but should be monitored closely for development of pain/swelling and followed yearly with radiographs and MRI. Skeletally immature athletes with symptomatic yet stable OCD lesions are managed nonoperatively with an unloader brace and activity modification. Unstable lesions are managed surgically, based on quality of the lesion. Salvageable lesions are treated with fixation +/- bone grafting while unsalvageable lesions are excised and treated with subsequent autologous chondrocyte implantation (ACI).

Crawford et al authored a review article on OCD lesions of the knee. During the early work up of an OCD lesion, plain radiographs should be obtained to provide initial data regarding location, size and presence of sclerosis. MRI is valuable to determine quality of the cartilage and lesion stability. Signs of instability on MRI include high signal intensity behind the lesion on T2 images, high signal extending from the joint surface indicating a cartilage breach, and loose bodies.

Polousky et al reviewed the etiology, natural history and proposed management of juvenile OCD lesions. Stable OCD lesions should be managed with nonoperative treatment for a minimum of 6 months. Surgical management is recommended for stable lesions that have failed conservative management or unstable lesions. Stable lesions can be treated with arthroscopic drilling, either retrograde or antegrade, to stimulate healing. Options for unstable lesions include fixation (metallic screw, bioabsorbable implants or biologic fixation with osteochondral plugs) versus salvage procedures (microfracture, OATS and ACI).

Illustration A is a treatment algorithm from Crawford et al.

Incorrect Responses:
Answers 1, 2, 4, 5: Open physes, location at the lateral aspect of the medial femoral condyle, lesion size < 2cm and stable appearance on MRI with an intact articular surface and no lesion fragmentation all confer a good prognosis with nonoperative management.