Osteochondritis Dessicans is a condition that can affect children and adolescents where there is softening of the bone underneath the joint cartilage. This commonly affects the knee joint, ankle joint and occasionally the elbow. Some patients will get pain with this condition and in some patients, pieces can actually break off, float in the joint and cause locking. If surgical treatment is required, the treatment algorithm depends on whether the cartilage joint surface is intact or not. We determine this with a combination of diagnostic imaging modalities as well as joint arthroscopy. If it is, we leave the cartilage undisturbed and then use a technique called 'anterograde or retrograde drilling' which involves feeding in a small wire into the soft bone under x-ray guidance, drilling over the wire in an effort to stimulate healing, usually in the distal femur or the talus (ankle). If there is a defect in the cartilage, classic technique involves stimulating bleeding in the underlying bone in an effort to stimulate scar-cartilage formation. Either way, the patient must be non-weightbearing, sometimes requiring splint immobilization, for 6 weeks on the affected side.
Note about Arthroscopy:
Arthroscopy is an orthopedic surgical technique where small incisions are made to insert a 2.9mm-4.2mm diameter camera into the joint while fluid runs into the joint allowing visualization of pathology as well as treatment of various conditions.
Ankle arthroscopy is useful for multiple ankle conditions including: removal of loose cartilage or bone pieces, removal of bone spurs, inspection and drilling/treatment of osteochondritis desiccans lesions as well as cleaning out an infected ankle joint. It can be a very effective treatment in these conditions but is not useful in advanced osteoarthritis of the ankle. Knee arthroscopy is common for osteochondritis, meniscal tears, removal of loose bodies (usually floating pieces of cartilage) as well as for assistance with some joint trauma management and ligament reconstructions.
Surgical intervention usually involves a general anaesthetic or a spinal anesthetic in older patients. A tourniquet is applied to the thigh and is often inflated to limit bleeding and improve visualization in the joint. Two or three small incisions are made, and these facilitate the probing of the anatomic structures in the joint, as well as treatment.