Hip resurfacing

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BHR compared with THR
BHR compared with THR
The BHR
The BHR

Hip resurfacing is a form of arthroplasty which has been developed as an earlier intervention alternative to total hip replacement (THR). The potential advantages of hip resurfacing include less bone removal (bone preservation), a potentially lower number of hip dislocations due to a relatively larger femoral head size, and possibly easier revision surgery for a subsequent total hip replacement device because a surgeon could have more bone stock available to work with.[1] The potential disadvantages of hip resurfacing are femoral neck fractures (rate of 0-4%), aseptic loosening, and metal wear.[2]

Patient suitability for hip resurfacing is decided by the patient's anatomy and the patient's doctor. Hip resurfacing is intended for younger patients who are not morbidly obese, are clinically qualified for a hip replacement (determined by the doctor), have been diagnosed with noninflammatory degenerative joint disease, do not have an infection, and are not allergic to the metals used in the implant.[3] Hip resurfacing should not be used on patients who have severe bone loss in their femoral head, those with large femoral neck cysts present (typically found at surgery), or patients who have poor bone stock in the acetabulum.[4] Caution should be used for patients who have rheumatoid arthritis, are tall, thin, or female, those with osteonecrosis (poor blood supply) to the femoral head, or those with femoral head cysts > 1cm on an x-ray taken before surgery.[5] Patients with any of these conditions may not be suitable candidates for hip resurfacing.

In the United States, the FDA approved hip resurfacing using the Birmingham Hip Resurfacing (BHR) on May 9, 2006.[6] Derek McMinn designed the Birmingham Hip Resurfacing in Birmingham, England and released it for use in the UK in July 1997.[7] Both BIRMINGHAM HIP and BHR are registered trade marks of Smith & Nephew, who are now the exclusive manufacturers and distributors of the BIRMINGHAM HIP Resurfacing System. On July 3, 2007, the FDA approved an alternative hip resurfacing system made in the UK by Corin Group and marketed in the US by Stryker. [8]. Stryker/Corin also recently received FDA approval for their resurfacing product in the US.

The BHR is a metal on metal [9] hip device which differs from a total hip replacement device because it may be bone conserving. A THR requires that the upper portion of the femur bone be cut off to accept the stem portion of a THR hip device. The femur cap of the BHR does not require the femur bone be cut off, it is shaped to accept the cap. Both techniques require that a cup is placed in the acetabulum of the hip socket. The main advantage of the bone conserving system of the BHR is that when a revision is required, there is still a complete femur bone left for a THR stem. When a THR requires a revision, what is left of the femur bone must be broken apart to remove the stem and then the bone is wired together again to heal. Having a BHR at a younger age means that a revision may be easier to perform when required.

Hip resurfacing may allow younger, active people to return to any activities they enjoyed previous to their hip problems. The large size cap and cup of the BHR are the same size as a person's original femur bone and are designed to prevent dislocations. There are many athletes with resurfaced hips that continue to compete at the professional level in a myraid of activities. They include:

  • Cory Foulk finished a marathon three months after his surgery, and finished 11th in the Ultraman world championship eleven months later[10]
  • Jim Roxburgh continues to participate in the martial arts after having both hips resurfaced in 2004 [11]
  • Ian MacLaren of the Torashin Karate Club is believed to be the first 5th dan Karate-ka in the world to have had both hips resurfaced
  • Floyd Landis, 2006 Tour de France Winner[12]

[edit] References

  1. ^ Mont M.A. et al. Hip resurfacing arthroplasty. J Am Acad Orthop Surg. 2006;14(8): 454-63.
  2. ^ Mont M.A. et al. Hip resurfacing arthroplasty. J Am Acad Orthop Surg. 2006;14(8): 454-63.
  3. ^ Mont, M.A. et al. Effect of Changing Indications and Techniques on Total Hip Resurfacing. Clin Orthop Rel Res. 2007.
  4. ^ Mont M.A. et al. Hip resurfacing arthroplasty. J Am Acad Orthop Surg. 2006;14(8): 454-63.
  5. ^ Mont M.A. et al. Hip resurfacing arthroplasty. J Am Acad Orthop Surg. 2006;14(8): 454-63.
  6. ^ FDA approval for the BHR
  7. ^ McMinn Centre website
  8. ^ Barnaby J. Feder, FDA approves a hip resurfacing implant, New York Times, July 4, 2007
  9. ^ Reports of metal on metal devices
  10. ^ Ultraman 2006 Finish Results
  11. ^ Jim Roxburgh
  12. ^ floydlandis.com » Floyd Landis - 3 Month Hip Update

[edit] External links