Osteochondral lesions, sometimes called osteochondritis dessicans or osteochondral fractures, are injuries to the talus (the bottom bone of the ankle joint) that involve both the bone and the overlying cartilage.
These injuries may include blistering of the cartilage layers, cyst-like lesions within the bone underlying the cartilage, or fracture of the cartilage and bone layers. Throughout this discussion, these injuries will be referred to as osteochondral lesions of the talus (OLT).
Once the diagnosis has been confirmed, treatment may consist of either nonoperative or operative methods. The specifics of treatment will likely depend upon the nature of the OLT, presence of other injuries, and patient characteristics.
Nonoperative treatment is appropriate for certain lesions and usually involves immobilization and restricted weight bearing. This may then be followed with gradual progression of weight bearing and physical therapy. The goal of nonoperative treatment is to allow the injured cartilage and bone to heal.
Other lesions may be more appropriately treated with surgery. The goals of surgery are to restore the normal shape and gliding surface of the talus in order to re-establish normal mechanics and joint forces. The hope is to minimize symptoms and limit the risk of developing arthritis. Depending on the characteristics and location of the OLT, surgery may be done arthroscopically or open.
Arthroscopy uses a camera and small instruments to view and work within the joint through small incisions. It may not be possible to properly treat certain lesions arthroscopically due to the size or location of the lesion.
Treatments may include debridement (removing injured cartilage and bone), fixation of the injured fragment, microfracture or drilling of the lesion, and/or transfer or grafting of bone and cartilage. Your surgeon and you can discuss these treatment options and decide which one is best for you.
Anticipated recovery after an osteochondral lesion varies depending upon the nature of the lesion and the treatment. Most treatments require a period of immobilization and restricted weight bearing that can range from several weeks to several months. More involved procedures that include bone grafting or cartilage transfer may require a longer period of recovery.
The results of nonoperative treatment of OLTs have been disappointing. Most studies show that full resolution of the pain from an OLT occurs in less than half of cases treated without surgery. Studies examining the outcomes after debridement and microfracture (drilling) of OLTs have shown that the majority (greater than 70%) of patients have a good or excellent outcome. Procedures that transfer bone or cartilage to an OLT also have good outcomes. In general, the best results can be expected for smaller lesions.
Complications, such as infection or wound healing problems, are uncommon after arthroscopic ankle surgery. More complex procedures with an open approach or bone or cartilage transfer may have additional risks. In addition to standard surgical risks, additional complications may include failure of healing of the transplanted tissue, poor healing of bone cuts (osteotomies) necessary to gain access to the joint, or symptoms at the site of bone or cartilage harvest.
*Source: American Orthopaedic Foot & Ankle Society® http://www.aofas.org