Osteonecrosis

Abstract

Osteonecrosis, literally "bone death," is the loss of viable bone tissue Up to 10% of all hip replacement procedures in the U.S. are performed for osteonecrosis. Major risk factors for osteonecrosis include glucocor-ticoid use, alcohol, cigarette smoking, systemic lupus erythematosus (SLE), scuba diving, and major hip trauma, leading to disruption of the vascular supply to the femoral head. Patients who have identifiable risk factors for osteone-crosis are said to have secondary osteonecrosis. Idiopathic osteonecrosis occurs in some individuals without overt risk factors for the disorder. Clinical outcomes are better in patients who are treated at early stages of the disease. Patients who have large osteonecrotic lesions or femoral head collapse at the time of presentation will typically progress to end-stage degenerative disease requiring joint arthroplasty. Magnetic resonance imaging (MRI) is the study of choice for patients in whom there is a high index of suspicion of osteonecrosis. Core decompression is a relatively noninvasive joint preservation technique that may be effective if applied to patients with early disease. Hip resurfacing is a joint arthroplasty technique that requires less resection of native bone compared with traditional joint arthroplasty procedures. © 2010 Springer-Verlag London.