Internal Medicine

0521779407-16 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:18

Osteonecrosis 1107

differential diagnosis

■Osteoarthritis of hip involves both femoral head and acetabulum

early in course; late-stage osteonecrosis indistinguishable from late-

stage osteoarthritis

■Inflammatory arthritis of hip: no characteristic radiographic changes

of osteonecrosis

■Synovial osteochondromatosis, synovial tumors, labrum tears:

detected by specific imaging findings

■Transient osteoporosis of hip: similar on radiographic and radionu-

clide scan; differs on MRI

management

What to Do First

■Plain x-rays will detect bone changes; if normal, MRI

General Measures

■Minimize alcohol intake and corticosteroid use

■Control hyperlipidemia, diabetes, sickle cell disease, renal failure

■Education for divers on slow decompression

■Analgesics, NSAIDs, canes

■Limited weightbearing; weight loss if obese

specific therapy

■No specific medical treatments other than analgesics

■Surgical Treatment

➣Core decompression of femoral head:

Decreases intraosseous pressure

Prevents progression

Useful in stages 0 to 2

➣Core decompression with bone grafting or free vascularized fibu-

lar graft:

Decreases intraosseous pressure

Promotes growth of viable bone

Useful in stages 0 to 2

Outcomes may be better than decompression alone

■Osteotomy:

➣Prevents collapse of femoral head by redirecting mechanical load

➣Can preserve femoral head in young patients

➣Useful in stage 3

■Femoral head replacement useful in stage 4

■Total hip replacement useful in stages 4 to 6