IMPORTANT NOTE: JAAPA CME activities consist of 2 articles. To obtain credit, you must also read
Stress management: Helping patients to find effective coping strategies; the post-test will include questions related to both articles. AAPA Fellow members should complete and submit the post-test on the AAPA Web site by going to
www.aapa.org and searching for keyword
JAAPA post-tests. All others may complete and submit the post-test online at no charge at
www.mycme.com. To obtain 1 hour of AAPA Category I CME credit, PAs must receive a score of 70% or better on each test taken.
KEY POINTS
■ The advantages of hip resurfacing as opposed to total hip arthroplasty are minimal bone resection, physiologic transfer of stress to the proximal femur, lower risk of dislocation, and the potential for a higher level of activity after surgery. Hip resurfacing also allows for conversion to total hip arthroplasty in the event of implant failure.
■ The optimal candidates for hip resurfacing are males younger than 65 years with normal hip morphology. Older men and women with poor bone density experience a much higher failure rate. Women are particularly at risk because female bone density drops off significantly after menopause.
■ A primary concern for patients who are interested in resurfacing is avascular necrosis. Osteonecrosis is extensive in resurfaced femoral heads that fail by fracture and is likely to play a role in the causation of the fracture.
■ Femoral head destruction or leg length discrepancy is a disqualifi er for hip resurfacing. The implant requires a normal hip morphology.
Hip resurfacing fell out of favor in the United States during the late 1970s and early 1980s because of a high failure rate compared with traditional hip arthroplasty. However, the procedure is now offered as a viable alternative to total joint replacement for many patients. This article explores the various factors that affect the decision to recommend hip resurfacing instead of hip arthroplasty.
Early failures of resurfacing implants were the result of suboptimal materials used at the time. The friction of a
large-diameter metal head against a polyethylene acetabulum or a polyethylene femoral head against a metal acetabulum produced excessive plastic debris. The resultant osteolysis caused the components to loosen and, ultimately, implant failure.
Hip resurfacing has made a comeback in the past 2 decades primarily because of improvements in the implants, such as large-diameter metal-on-metal articulating surfaces, enhanced metallurgy, and improved manufacturing of components. Current data on hip resurfacing indicate that 10-year implant survival rates are equivalent to those of traditional hip arthroplasty.
The advantages of hip resurfacing as opposed to total hip arthroplasty are minimal bone resection, physiologic transfer of stress to the proximal femur, lower risk of dislocation, and the potential for a higher level of activity. Hip resurfacing also allows for conversion to total hip arthroplasty in the event of implant failure. Many younger patients actively seek hip resurfacing as an alternative to traditional hip replacement because of these potential advantages. Unfortunately, the procedure is not for every patient.
Hip resurfacing is more efficacious in males younger than 65 years with good bone quality. The failure rate seen in males older than 65 years, females, and patients with poor bone quality is much higher than the failure rate seen in males younger than 65 years. The goal of resurfacing is to enable the patient to live a pain-free, active life.