eMedicine Specialties > Orthopedic Surgery > Hip

Osteonecrosis, Hip: Treatment

Author: Michael Levine, MD, Chairman, Department of Orthopedic Surgery, Western Pennsylvania Hospital
Coauthor(s): Amar Rajadhyaksha, MD, Resident, Department of Orthopedic Surgery, New York Medical College; Michael Mont, MD, Associate Professor, Department of Orthopaedic Surgery, Johns Hopkins Medical Institution
Contributor Information and Disclosures

Updated: Mar 26, 2009

Treatment

Medical Therapy

Nonsurgical treatment of osteonecrosis is limited. Observation and protected weight bearing are options. Certain cases of early-stage disease (eg, Ficat stage 1) can be treated successfully with this option. However, most studies indicate that the risk of disease progression is greater with nonsurgical treatment than with surgical intervention.

Nonsteroidal anti-inflammatory drugs can be used to reduce pain and inflammation in patients who cannot have surgery for medical or other reasons or for patients who are undergoing surgical treatment.

Physical therapy can be helpful to restore motion and improve gait.

Electrical stimulation has been used in several centers. In some studies, it has been helpful in treatment prior to femoral head collapse. The benefit of surgical treatment options versus observation is controversial in certain cases. Further study is required.

Pharmacotherapy that addresses the pathophysiology of the disease has had mixed results. Examples include gemfibrozil (Lopid) for hyperlipidemias and nifedipine for vascular disorders. Short-term follow-up (about 24 months) of patients in alendronate studies have demonstrated delayed femoral head collapse.⁵

Extracorporeal shockwave treatment has shown some promise in treating early disease by promoting angiogenesis and bone remodeling.⁶

Surgical Therapy

The mainstay of treatment for osteonecrosis is surgical. Numerous procedures are available, indicating that no single procedure is distinctly advantageous. Preoperative staging, particularly with collapse of the femoral head, and acetabular involvement are the determining factors for choosing a particular operation.

Preoperative Details

The choice of procedure is based on preoperative staging. Core decompression and cancellous and cortical bone grafting procedures usually are indicated in Ficat stage IIa or earlier stages. The trapdoor procedure and allograft procedures are indicated for stage IIb or stage III lesions. Osteotomies are used for stage II and stage III disease. Arthrodesis and arthroplasty are utilized primarily for stages III and IV but occasionally are used for stages I and II.

Intraoperative Details

The objective in core decompression is to stimulate revascularization and decrease pressure within the femoral head. The patient is placed supine on a fracture table. Using image intensification through a lateral incision above the trochanteric ridge, a 10-mm core of bone is removed from the femoral necrotic lesion.

Bone grafting has several techniques.

• Cancellous bone grafting: A core decompression is performed. The defect is filled with cancellous bone graft material, usually iliac crest or allograft.
• Cortical bone grafting: A core decompression is performed, and a strut graft is placed in the defect under the weightbearing surface of the femoral head. Iliac crest or fibula has been used. Recently, use of a vascularized free fibular graft harvested from the ipsilateral leg with a vascular pedicle inserted into the proximal femoral defect and anastomosed with the lateral circumflex artery has become popular.
• Osteochondral allograft procedure: The necrotic area is replaced with a nonvascularized free allograft.
• Muscle pedicle bone grafting: This procedure was adapted primarily for traumatic osteonecrosis. Cancellous iliac crest graft is placed in a channel in the infracted region and covered by a graft with the quadratus femoris muscle attached.
• The growth factors Op-1 (osteogenic protein-1) and rhBMP-2 (recombinant human bone morphogenetic protein-2) may be useful bone grafting adjuncts.⁷
• Implantation of mesenchymal stromal cells is currently under investigation.⁸
• Strut grafting with a tantalum implant, a highly porous metallic cylinder placed in a channel to support subchondral bone.⁹

 The concept in osteotomy is to rotate the diseased area of the femoral head away from the weightbearing surface. Several different techniques are available.

• Angular osteotomy: Varus or valgus flexion usually is performed intertrochanterically and fixed with a plate.
• Rotational osteotomy: The head is rotated transtrochanterically, moving the weightbearing surface away from the necrotic lesion.

Arthrodesis is fusion of the hip joint. The joint is denuded of articular cartilage, and the femoral head and acetabulum are fixed to create a solid interface.

In arthroplasty, conventional techniques are used with either cemented or cementless implants.

• Resection arthroplasty involves excision of the femoral head.
• Mold or cup arthroplasty involves resurfacing of the articular surface of the femoral head with a prosthetic device.
• Resurfacing arthroplasty involves a cup-type arthroplasty on the femoral side with a metal-on-metal acetabular component. 
• Unipolar prosthetic arthroplasty involves replacement of the femoral head with a nonmobile bearing head.
• Bipolar arthroplasty involves replacing the femoral head with a mobile bearing component.

The trapdoor procedure involves open excision of the necrotic bone by elevation of the cartilage and cancellous grafting.

Limited femoral resurfacing for young patients with intact acetabular cartilage and a collapsed femoral head is a valuable alternative to total hip replacement. Total hip replacement, with a femoral and an acetabular component, currently is the end result of the disease.

Postoperative Details

• Core decompression - Non-weightbearing ambulation for 6-12 weeks, then gradual resumption of normal activities as tolerated
• Cancellous bone grafting - Similar to core decompression
• Cortical bone grafting - No weight bearing for 6 weeks, with progressive weight bearing to 6 months
• Trapdoor - Twenty percent weight bearing for 6 weeks, 50% weight bearing to 10 weeks, then progress to full weight bearing
• Arthrodesis - No weight bearing, with full weight bearing initiated at 3 months
• Osteotomy - Protected weight bearing for 6 weeks with gradual progression
• Limited femoral resurfacing - Fifty percent weight bearing for 6 weeks, then weight bearing as tolerated
• Resurfacing arthroplasty - Rehabilitation similar to total hip arthroplasty
• Arthroplasty - Weight bearing as tolerated immediately following surgery, depending on surgeon preference

Follow-up

• Core decompression: Success rates are better than those with conservative treatment, with approximately 70% success in stages before radiographic collapse and limited morbidity.¹⁰ Core decompression has been shown to be a highly cost-effective alternative when a total hip replacement is delayed by 5 years or more.
• Cancellous grafting: No statistical evidence exists of superiority over core decompression alone.
• Cortical grafting (avascular): No evidence exists of superiority over core decompression.
• Vascularized fibular grafting: The procedure is technically difficult with increased morbidity and has questionable benefit compared with core decompression.
• Tantalum implants: Recent retrieval studies have shown little bone ingrowth, insufficient mechanical support of subchondral bone, and a significant rate of femoral head collapse.¹¹
• Trapdoor: Indicated more in stage III disease, in which above procedures are unsuccessful; 83% good or excellent results were demonstrated in 1 study.¹²
• Osteotomy: This procedure is technically very difficult; use in cases in which total hip replacement is not advisable, understanding that future total hip replacement is technically more difficult.
• Cup arthroplasty, unipolar arthroplasty, and bipolar arthroplasty: Success rates are poor; disease appears to affect both sides of the hip joint.
• Limited femoral resurfacing: Newer designs have increased the longevity of the procedure to greater than 10 years. Therefore, limited femoral resurfacing is a valuable alternative to total hip replacement in young patients with osteonecrosis; however, some studies suggest poor results when compared with age-matched patients with osteoarthritis.
• Total resurfacing arthroplasty: Greater than 90% survivorship at greater than 3 years
• Arthrodesis: Results are poor in terms of achieving fusion and patient satisfaction.
• Total hip replacement: Early results were poor with early cement techniques, with failures up to 25% or higher. Recent studies have shown success rates at over 90% with current techniques, making it the treatment of choice following collapse or failure of less-invasive procedures.

Complications

• Core decompression: Complications are minimal in the hands of experienced surgeons. The most severe complication is fracture, which can occur if core is drilled below the trochanteric ridge.
• Bone grafting procedures: The same complications as with core decompression, along with donor-site morbidity; peroneal sensory neuropathy, contractures of the flexor hallucis longus, deep venous thrombosis, and ankle pain with ambulation have been noted in vascularized fibular graft procedures.
• Trapdoor: Limited complications are reported aside from deep venous thrombosis.
• Osteotomies: Complications include nonunion and malunion, along with those stated above.
• Limited femoral resurfacing: Cases of loosening and acetabular wear have been reported but complications are minimal.
• Total resurfacing arthroplasty: Femoral neck fracture is the most common and critical complication; patient selection is key. 
• Total hip replacement: Infection, peroneal nerve palsy, deep venous thrombosis, intraoperative fracture, and postoperative dislocation are noted; risk-benefit ratio strongly reflects success of procedure.

• Search for CME/CE on This Topic »

• Joint Reduction, Hip Dislocation, Posterior (Clinical Procedures)
• Osteonecrosis, Shoulder (Orthopedic Surgery)
• Femoral Osteotomy (Orthopedic Surgery)
• Legg-Calve-Perthes Disease (Emergency Medicine)

• Total Hip Replacement Introduction
• Breaks, Fractures, and Dislocations Center
• Total Hip Replacement Preparation

• Denosumab Linked to Lower Fracture Rate in Postmenopausal Women With Osteoporosis
• Zoledronic Acid Prevents Bone Loss in Postmenopausal Women With Osteopenia
• Zoledronic Acid Injection Approved to Prevent Postmenopausal Osteoporosis

• Male Osteoporosis: New Insights in an Understudied Disease
• Preventing Nonvertebral Osteoporotic Fractures With Extended-Interval Bisphosphonates: Regimen Selection and Clinical Application
• Clinical Significance of HIV-associated Bone Loss: When and how to Intervene

• Arthroplasty Resource Center
• Joint Replacement
• Joint Disorders Resource Center