Percutaneous drilling is a type of bone decompression surgery that is relatively new. This technique differs slightly from other core decompression techniques in that it uses smaller drill bits and is thus less invasive and removes less bone. It has been the subject of recent attention as it has been successful in treating osteonecrosis in the femoral head, knee, shoulder, and ankle. Post-operatively, you will expect to be partial weight bearing for four weeks using crutches, progressing to full weight bearing thereafter. You will be restricted with no high impact activities for ten months. There is limited research looking at long term results of percutaneous drilling, however one recent research study looking at 101 patients found that at long term follow up there were significant improvements in the patient reported outcome measures and pain scores. Of the 101 patients, 83 per cent of the ankles demonstrated no further progression of osteonecrotic lesions. Seventeen of the ankles in this study had progressed to a more advanced stage, four of which were at joint collapse, however the presence of sickle cell disease and HIV was associated with this progression.