In this brief document, members of the American Academy of Orthopaedic Surgeons provide a 16-point clinical practice guideline for the treatment of osteochondritis dissecans (OCD). Although OCD can affect several areas of the body (ankle, elbow, knee), this review is strictly limited to the diagnosis and treatment of the knee.
When osteochondritis dissecans (OCD) that affects the knee, it’s mostly at the end of the big bone of the thigh (an area called the femoral condyles. A joint surface damaged by OCD doesn’t heal naturally. Even with surgery, OCD can lead to future joint problems, including degenerative arthritis and osteoarthritis.
That’s why guidelines to the care and management of this problem are important. Informing surgeons of the best practice for this condition can aid them in helping patients obtain the best results possible.
The problem occurs where the cartilage of the knee attaches to the bone underneath. The area of bone just under the cartilage surface is injured, leading to damage to the blood vessels of the bone. Without blood flow, the area of damaged bone actually dies. This area of dead bone can be seen on an X-ray and is sometimes referred to as the osteochondritis lesion.
The lesions usually occur in the part of the joint that holds most of the body’s weight. This means that the problem area is under constant stress and doesn’t get time to heal. It also means that the lesions cause pain and problems when walking and putting weight on the knee. It is more common for the lesions to occur on the medial femoral condyle, because the inside of the knee bears more weight.
Nonsurgical treatments help in about half the cases of OCD affecting children (called juvenile OCD or JOCD). The goal is to help the lesions heal before growth stops in the thighbone. Even if imaging tests show that growth has already stopped, it is usually worth trying nonsurgical treatments. When these treatments work, the knee seems as good as new, and the JOCD doesn’t seem to lead to arthritis.
Some patients who are too near the end of bone growth may not benefit with nonsurgical treatment. Surgery may also be advised if and when the lesion becomes totally or partially detached. There are several ways to fix it in place. In some cases, the loose fragment will just have to be removed.
So, what are the new guidelines? Anything really new from the way things have been done? Well, first of all, most of the evidence from studies currently available is weak or inconclusive. For example, the committee was unable to recommend for or against nonoperative care for children with OCD that does not cause pain or other symptoms. Likewise, the committee was unable to recommend for or against surgical drilling in patients with symptoms after nonoperative care but with a stable lesion.
Other areas where the research remains inconclusive include: 1) whether or not to take X-rays of the other knee once OCD has been discovered, 2) which type of cartilage repair works best when surgery is needed, 3) whether to treat patient with or without symptoms who are fully grown (skeletally mature) in a similar fashion, and 4) whether or not patients should have repeat or follow-up MRIs when they are skeletally mature without symptoms.
There are some areas where the committee could offer guidelines based on agreement (referred to as consensus). Consensus means the committee agrees on the recommendation even though there isn’t enough reliable evidence to prove the guideline is accurate. For example, most experts agree that skeletally immature patients should be offered surgical correction when the lesion is unstable or shifted but still salvageable.
Likewise, the committee agreed that symptomatic patients who are skeletally mature should be offered surgery when the lesion is unstable or displaced. After surgery, all patients should be provided with physical therapy. X-rays and/or MRIs should be taken to assess healing after treatment, especially for those who are still experiencing painful symptoms.
The committee made it clear that this document is just a quick summary of current guidelines. No explanation is given as to the ‘whys’ or ‘wherefores’ of the recommendations. The full guideline with evidence cited is available for anyone interested in reading it. And as always, each patient must be evaluated and treated on an individual basis. Decisions made about management and treatment techniques to use are determined by the patient in consultation with the physician.