boivette
junior member
- Joined
- Jul 2, 2008
- Messages
- 27
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- Male
Hip resurfacing arthroplasty (RA) is a surgical technique in which the surface of the femoral head is covered with a metal cap. Initially, only the femoral side was addressed, but because metal articulating against cartilage frequently causes pain, surgeons introduced an acetabular component as early as the 1960’s. These components were less successful than low-friction total hip replacement (THA). As such hip resurfacing never gained the same level of popularity and success as the more traditional total hip replacement.
With improved understanding of lubrication mechanisms and improved manufacturing techniques, metal-on-metal hip resurfacing re-emerged as a viable treatment alternative in the early to mid 1990’s. The theoretical advantages of this type of hip replacement are: less bone removal from the femoral side, a larger diameter articulating ball, more stability (and a lower dislocation incidence), simpler surgery when revision of the components is needed, and what patients describe as “a more normal feeling” hip. Also, the metal-on-metal articulation has the same advantage of other metal-on-metal bearings, namely reduced wear. Theoretical disadvantages include: more difficult surgical technique, equal or more bone removal on the acetabular side, lack of supplemental acetabular fixation besides the initial press-fit in most systems, femoral neck fracture, higher metal ion exposure from the the metal-on-metal articulation, and femoral head avascular necrosis/collapse leading to femoral component failure.
Despite conflicting claims from proponents and skeptics, the state of the current data is inconclusive to determine whether hip resurfacing is superior (or even equal) to total hip replacement. For example, Lavigne et al (1), Mont et al (2) and Naal et al (3) have recently reported higher activity levels in RA patients compared to THA patients. However, in all these studies, the RA patients started with a higher functional activity level. Le Duff et al (4) reported that RA implants had a higher survival rate in obsess patients specifically because they were less active than THA patients. Shimmin et al (5) found no difference in gait analysis between RA and THA patients. The Australian hip resurfacing registry (6) includes data on over 10,000 RA procedures. The revision rate, compared to THA, was higher in women, men over age 65, and patients with avascular necrosis, inflammatory arthritis (such as rheumatoid arthritis) and dysplasia of the hip. Only men under 65 demonstrated equal revision rates when comparing THA to RA.
As of late 2008, RA represents another treatment option for patients with hip disease. As always, the decision for undergoing RA or THA should be undertaken after a thorough discussion with your surgeon. Neither THA nor RA is the correct choice for ALL patients. Lastly, choose a surgeon with extensive experience in perfoming RA.
References:
1. Lavigne et al, Rev Chir Orthop Reparatrice Appar Mot. 2008; 94(4): 361-367.
2. Mont et al, Clin Orthop Relat Res. 2008 Epub.
3. Naal et al, Am J Sports Med. 2007; 35(5):705-11.
4. Le Duff et al, JBJS (A) 2007;89:2705-2711.
5. Shimmin et al, J Bone Joint Surg Am. 2008; 90(3): 637-654.
6. Buergi ML and Walter WL, J. Arthroplasty, 2007; 22(7), Supp. 3: 61-65.
With improved understanding of lubrication mechanisms and improved manufacturing techniques, metal-on-metal hip resurfacing re-emerged as a viable treatment alternative in the early to mid 1990’s. The theoretical advantages of this type of hip replacement are: less bone removal from the femoral side, a larger diameter articulating ball, more stability (and a lower dislocation incidence), simpler surgery when revision of the components is needed, and what patients describe as “a more normal feeling” hip. Also, the metal-on-metal articulation has the same advantage of other metal-on-metal bearings, namely reduced wear. Theoretical disadvantages include: more difficult surgical technique, equal or more bone removal on the acetabular side, lack of supplemental acetabular fixation besides the initial press-fit in most systems, femoral neck fracture, higher metal ion exposure from the the metal-on-metal articulation, and femoral head avascular necrosis/collapse leading to femoral component failure.
Despite conflicting claims from proponents and skeptics, the state of the current data is inconclusive to determine whether hip resurfacing is superior (or even equal) to total hip replacement. For example, Lavigne et al (1), Mont et al (2) and Naal et al (3) have recently reported higher activity levels in RA patients compared to THA patients. However, in all these studies, the RA patients started with a higher functional activity level. Le Duff et al (4) reported that RA implants had a higher survival rate in obsess patients specifically because they were less active than THA patients. Shimmin et al (5) found no difference in gait analysis between RA and THA patients. The Australian hip resurfacing registry (6) includes data on over 10,000 RA procedures. The revision rate, compared to THA, was higher in women, men over age 65, and patients with avascular necrosis, inflammatory arthritis (such as rheumatoid arthritis) and dysplasia of the hip. Only men under 65 demonstrated equal revision rates when comparing THA to RA.
As of late 2008, RA represents another treatment option for patients with hip disease. As always, the decision for undergoing RA or THA should be undertaken after a thorough discussion with your surgeon. Neither THA nor RA is the correct choice for ALL patients. Lastly, choose a surgeon with extensive experience in perfoming RA.
References:
1. Lavigne et al, Rev Chir Orthop Reparatrice Appar Mot. 2008; 94(4): 361-367.
2. Mont et al, Clin Orthop Relat Res. 2008 Epub.
3. Naal et al, Am J Sports Med. 2007; 35(5):705-11.
4. Le Duff et al, JBJS (A) 2007;89:2705-2711.
5. Shimmin et al, J Bone Joint Surg Am. 2008; 90(3): 637-654.
6. Buergi ML and Walter WL, J. Arthroplasty, 2007; 22(7), Supp. 3: 61-65.
United Kingdom
