Osteochondritis dissecans of the knee

SummaryOsteochondritis dissecans (OCD) characterises a disease process predominately affecting male teenagers and young adults which, as its end-product, yields the separation of osteochondral fragments from the joint surface. Although OCD may occur in many joints, the knee appears to be by far the most commonly involved. Hence painful locking in a teenage knee should always raise the suspicion of OCD. The cause of the disease remains unclear and many theories have been developed, none of which has received unequivocal agreement. A multifactorial aetiology including elements of repetitive trauma and vascular insufficiency is henceforth considered most likely.The fundamental principle in the treatment of OCD is the timely recognition of the condition as lesions in the early disease process are more likely to be treated successfully. Proper initial assessment and grading of the lesion will allow for the right treatment protocol to be chosen. MRI may help in the staging process and in determining the lesions healing potential. Most cases fair well with conservative measures. In more advanced stages of the disease, surgical intervention ranging from subchondral drilling to fragment refixation may be required. The primary aim of any intervention is to achieve healing of the subchondral bone, and preservation of the articular cartilage as fragment separation may pave the way for subsequent development of osteoarthritis.