Patients with advanced arthritis of the hip may be candidates for either traditional total hip replacement (arthroplasty) or hip resurfacing (hip resurfacing arthroplasty). Each of these procedures is a type of hip replacement, but there are important differences. Your orthopaedic surgeon will talk with you about the different procedures and which operation would be best for you.
Advantages of Hip Resurfacing
The advantages of hip resurfacing over traditional total hip replacements is an area of controversy among orthopedic surgeons. A great deal of research is currently being done on this topic.
- Hip resurfacing may be easier to revise. Because the components (called implants) used in hip replacements and hip resurfacings are mechanical parts, they can — and do — wear out or loosen over time. This typically occurs between 10 and 20 years after the procedure, although implants may last longer or shorter periods of time.
If an implant fails, an additional operation may be necessary. This second procedure is called a revision and it can be more complicated than the initial operation. Because hip resurfacing removes less bone from the femur (thighbone) than a traditional hip replacement, many surgeons believe it is easier to exchange implants that fail after hip resurfacing.
- Decreased risk of hip dislocation. In hip resurfacing, the size of the ball is larger than in a traditional hip replacement, and it is closer to the size of the natural ball of your hip. Because of this, it may be harder to dislocate. This stance is controversial because several factors can affect the risk of dislocation, such as surgical approach, and the type and size of the implants used.
- More normal walking pattern. Several studies have shown that walking patterns are more natural following hip resurfacing compared to traditional hip replacement. These differences in walking are quite subtle, however, and special instruments are needed to measure them.
Disadvantages of Hip Resurfacing
- Femoral neck fracture. A small percentage of hip resurfacing patients will eventually break (fracture) the thighbone at the femoral neck. If this occurs, it is usually necessary to convert the hip resurfacing into a traditional hip replacement.
A femoral neck fracture is not possible with a traditional hip replacement because the femoral neck is removed during this procedure. However, fractures around the implants can still occur with a traditional hip replacement.
- Metal ion risk. In hip resurfacing, a metal ball moves within a metal socket. Over time, this leads to the production of tiny metal particles called ions. Some patients may develop sensitivity or allergy to the metal particles, which may cause pain and swelling. Also, there are concerns that the metal particles may increase the risk of cancer, although this has never been proven. Some types of traditional hip replacements also consist of a metal ball and a metal socket and these replacements run the same potential risks. Ask your doctor for more information about metal-on-metal implants.
- Hip resurfacing is a more difficult operation. Hip resurfacing is more difficult than total hip replacements for surgeons to perform. As such, a larger incision is usually required for a hip resurfacing.