An osteochondral defect occurs when a chunk of joint cartilage is lost, leaving a crater that extends into the underlying bone.
Causes of osteochondral defects
Deep craters involving both the cartilage and the bone may be a result of impact or a condition such as osteochondritis dissecans where bood supply fails to an area of bone, and the bone and cartilage die.
MRI of Osteochondral Defects of the Lateral Femoral Condyle: Incidence and Pattern of Injury After Transient Lateral Dislocation of the Patella Sanders TG, Paruchuri NB and Zlatkin MB. American Journal of Roentgenology > Volume 187, Issue 5 >.
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