Abstract
Introduction: Osteonecrosis of the hip is a devastating disease that often results in the collapse of the femoral head and secondary osteoarthritis of the hip. Although total hip arthroplasty is considered the main therapeutic option in cases of advanced osteonecrosis (Ficat stage III or IV), historically high failure rates have been reported for this treatment. Variables such as, whether or not the prosthesis was cemented, year of implantation, age, various medical comorbidities, and risk factors such as alcohol abuse, corticosteroids usage, autoimmune disease, or sickle cell anemia may lead to better or worse outcomes. The purpose of this study was to determine which factors were associated with risk for failure concerning total hip arthroplasty (THA) for osteonecrosis of the femoral head from a complete meta-analysis of the literature.
Methods: A systematic review utilizing the Medline bibliographic database found 35 studies meeting our inclusion criteria that were related to osteonecrosis encompassing 557 hips in 443 patients. These reports were published between the years 1989 to 2007. The mean follow-up was 6.7 years (range, 3 – 10). The study population comprised of 60% men who had a mean age of 47 years (range, 17 to 90). The most frequent associated risk factors for osteonecrosis were corticosteroid usage (26.2%) and alcohol abuse (30.1%). The final outcome parameters were number and percentage of patients who underwent revision surgery, who had impending radiographic failure, such as osteolytic lesions in close proximity to the implant, or who were clinical failures. Clinical failure was defined as a value less than 70% of the maximum score of the relevant hip scoring system used.
All reviewed studies were divided into cemented, cementless, or hybrid fixation, as well as year of implantation (before and after 1990). In addition, patients were stratified according to comorbidities, age, gender, and various diagnostic and other risk factors (e.g. systemic lupus erythematosus, sickle cell disease, use of corticosteroids, alcohol abuse).
Results: Overall, there were 131 poor outcomes out of 557 hips (23.5%). Seventy-six revision surgeries were performed, with another 55 hips showing either radiographic signs of loosening or clinical failures. Cemented THA had a failure rate of 17.9%, while the cementless THA had a failure rate of 24.5%.
Overall outcomes were different for various risk factors; intake of corticosteroids led to a failure rate of 42.3%, alcohol abuse; 38.1%, posttraumatic disorders; 39%, and sickle cell anemia; 45.5%. Patients without known adverse risk factors had only 17% failures.
Discussion: Our findings further emphasize the poor results of total hip arthroplasty in patients with various risk factors such as alcohol abuse, use of corticosteroids, lupus, and sickle cell anemia. It also appears that patients without these adverse risk factors have a better survival rate. The importance of this study is that it may help the surgeon understand the risk of total hip arthroplasty in various stratified groups in patients with osteonecrosis.
The abstracts were prepared by Lynne C. Jones, PhD. and Michael A. Mont, MD. Correspondence should be addressed to Lynne C. Jones, PhD., at Suite 201 Good Samaritan Hospital POB, Loch Raven Blvd., Baltimore, MD 21239 USA. Email: ljones3@jhmi.edu
