Ankle OCD (Osteo-Chondritis Dissecans of the Talus)
Ankle OCD refers to an injury to the cartilage within the ankle joint, usually the talus bone. These can development after some type of trauma to the ankle (i.e. fracture or sprain). They can also develop spontaneously without any prior injury. In either case, the blood supply to the injured cartilage is poor, giving it little potential to heal. This area of cartilage and underlying bone can become detached from the surrounding bone, which can become loose in the joint. With time, as the cartilage injury progresses, arthritis can develop in the ankle.
Common symptoms are pain and swelling around the ankle. The pain is often deep and poorly localized. Plain x-rays often do not show cartilage injuries, especially early ones. The most common way we diagnose these is with a MRI or Cat scan of the ankle.
Treatment of these injuries can be challenging. It is unclear which lesions will progress to full cartilage loss leading to arthritis. Treatment depends upon how long the symptoms have been present, as well as the severity of the lesion (i.e. size, depth, surrounding arthritic changes). Initially casting or bracing may be attempted in an effort to heal or stabilize the lesion.
This is accompanied by periodic MRI’s to assess any progress in healing. This form of treatment may be more successful in smaller and less severe lesions.
The surgery for an ankle OCD attempts to either stimulate healing of the lesion or replace it with new cartilage. An arthroscopy of the ankle attempts to debride the lesion and stimulate healing of the lesion, which usually comes in the form of scar tissue mixed with cartilage. Post operative recovery involves 4-6 weeks of protected weight bearing to allow for healing of the lesion. Ankle arthroscopy may be more successful for smaller lesions. Another type of treatment may involve replacement of the injured cartilage with donor cartilage or cartilage from another part of the patient’s body (i.e. the knee.)
Post operative recovery involves at least two to three months of non-weight bearing in a cast to allow for the graft to heal into the surrounding bone. Another newer form of treatment involves harvesting of cartilage cells from the same patient, growing them in a lab for a period of time (usually weeks), then followed by re-implanting them into the ankle lesion. This procedure originated in the knee with good results. Early reports in the ankle have been encouraging.