Osteochondral lesions

Osteochondral lesions (OCLs) of the ankle are injuries to the talus (the bottom bone in the ankle joint) which by definition affect both the bone and overlying cartilage. The lesions can be graded from 1 to 5 but may present as a blistering of the cartilage layers, cyst-like lesions within the bone or fracture of the cartilage and bone layers.

They can occur as a result of one traumatic injury or can be a result of repeated trauma or altered alignment. Common symptoms include prolonged pain, swelling, catching and/or instability of the ankle. They are commonly caused after a severe ankle sprain and if pain persists for longer than you deem normal it may need further evaluation to rule out an OCL.

OCLs are generally diagnosed with a combination of clinical and special studies. Physical examination and history taking can increase suspicion of injury but generally an MRI of the ankle is taken to confirm the diagnosis. Significant OCLs can often be seen on plain x-ray but generally patients are sent for an MRI to confirm the extent of the injury.

Depending on the severity of the lesion non-operative treatment options may be utilised first. Periods of immobilisation and restricted weight bearing can allow injured cartilage and bone to heal however studies have shown poor long term pain relief meaning surgical intervention is often needed. Surgeries are generally done arthroscopically (placing a small camera into the joint) but some newer techniques including AMIC (replacing damaged cartilage with artificial cartilage) or OATS (taking sections of bone and cartilage generally from the knee) may need the procedure to be done as an open case.

Studies showing the outcomes of debridement (removal of damaged cartilage) and micro fracture (drilling) of OCLs is excellent with greater than 70% of patients having a good or excellent outcome. OATS procedures also have good outcomes but in general the best results can be expected for smaller lesions. Patients who have been treated using AMIC have gotten brilliant results also but because there is a lack of long term data available (5-10 year follow ups) its long-term effects are not known.

Recovery after OCL surgery varies wildly depending on the nature of the lesion and the treatment however most treatments require some period of immobilisation and restricted weight bearing in a special air cast boot. You will be given more information before any surgery is undertaken regarding the amount of time you will need to take off work or attend the clinic for reassessments and wound checks.