Osteonecrosis of the hip, a condition in which the bone tissue in the hip dies, affects mainly young, active patients. Its origin is unknown, making it more difficult to treat. The authors of this study undertook a research of the literature to find previously completed studies that investigated the causes and treatments for osteonecrosis of the hip.
The researchers reviewed the article for etiology (origin of the disease), pathophysiology (changes associated with the injury), evaluations, and both surgical and non-surgical treatments. The researchers found that although no distinct cause for osteonecrosis of the hip has been found, some factors appeared to be involved in the development. Among those were consumption of alcohol, high doses of corticosteroids, and abnormal clotting of the blood (coagulation, as well as some genetic factors.
For evaluations, physicians have been relying on magnetic resonance imaging (MRI), which has a 99 percent accuracy rate in detecting osteonecrosis of the femoral (thigh bone) head. The researchers noted that using MRI for diagnosis is helpful in following the progress of the disorder. They noted that the high fat content of the bone, detected by MRI may have a connection with the corticosteroids that is thought may induce some osteonecrosis. Testing also allows the physicians to classify the hip deterioration by severity.
When assessing treatments for osteonecrosis of the hip, the researchers found a desire to use pharmaceutical agents (medications) to treat first, not only as treatment but as prevention for patients who are thought to be at a higher risk of developing the disorder, such as those on high doses of steroids. These medications include alendronate, a medication given for osteoporosis, or thinning bones, enoxaparin, a medication given to thin the blood and reduce clotting time, and iloprost, a medication given to patients with a disease called pulmonary arterial hypertension. Both alendronate and iloprost showed promise but need further testing in order to prove their efficacy in treating osteonecrosis of the hip.
Some physicians have tried to treat the disorder with extracorporeal shockwave and pulsed electromagnetic field therapy. The short-term findings were promising but longer term trials are needed.
Surgery is the option when other treatments are not viable or do not work. The surgeons try to spare the femoral head but, at times, must do a total hip arthroplasty, a hip replacement. Other more novel treatments have also been tried. These include a process called a bone morphogenetic protein enhanced bone graft, which is aimed at preventing the disease from progressing.
The authors conclude that more testing must be done in order to gain a better understanding of the best treatments for osteonecrosis of the hip. They recommend that core decompression, with or without bone graft is likely the best method for lesions that have not yet collapsed, with replacements being performed for those that have collapsed. MRI for staging is a useful tool and allows physicians to stage and monitor the patients' progress.