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Hip Dysplasia Overview

Hip Replacement Revision and Hip Resurfacing

Unfortunately, the majority of THRs have a limited life. The success of a revision later on relies on the quality and quantity of available bone. Regular check-ups and X-rays to make sure the hip is working well will keep the revision relatively simple. Most, however, are caught when a fracture or dislocation occurs, making the revision more complex. In cases where there is not enough viable bone, grafts or special components are needed.

dislocated artificial hip X-ray
Charles McRae, M.D./ Visuals Unlimited/Getty Images
Hip replacement revision is often required after normal wear and tear. Issues like fractures and dislocations (shown) make revision more complicated.

Revision surgery comes with a few disadvantages:

  • The original component needs to be removed and new components put in its place, making for a longer surgery.
  • Longer incisions are often needed.
  • There is greater blood loss and post-operative pain.
  • Older patients' health and strength may compound problems.

Long-term results are typically excellent. However, complications are a little more frequent than with the original surgery. For patients who are young when they undergo a hip replacement, revision surgery is almost inevitable. However, the newer materials available seem to improve the overall life span of the artificial joint, lessening the number of necessary revisions.

Hip resurfacing is a newer hip replacement procedure with advantages for younger patients. Due to their age, these patients may need more than one procedure in their lifetime. Rather than removing the head and neck of the femur, only the head is trimmed, and a round metal cap is placed on it. The socket is fitted with a metal cup, and the body's own natural fluids lubricate the artificial joint.

The advantage of this procedure is that far less bone is removed, allowing for less complex and more successful future revisions. In a younger, more active patient, hip resurfacing uses a larger metal head, which helps to lower the risk of dislocation.

This procedure is relatively new. The first surgery of its kind was performed in Europe in 1997 and was only FDA approved in the U.S. in 2006. This means there is no long-term data regarding the surgery's success rate, although medium-term data looks promising. There is also a 2 percent risk of the femoral neck fracturing in the first 6 months. Hip resurfacing is not suitable for people with or at risk of osteoporosis. Hip resurfacing requires more than 70 percent contact between the bone and metal socket, and thus is not always an option for people with hip dysplasia.

Procedures like femoral osteotomy and periacetabular osteotomy can take care of hip dysplasia symptoms, like pain and range of motion difficulties, and they can prolong the amount of time before a necessary THR. But they do not actually fix the structural problem of a shallow socket. In these cases, the surgeon may determine that resurfacing is not a viable option only once the patient is on the table. In such cases, the doctor may choose to perform a replacement instead to avoid future dislocations and instability of the joint.

To learn more about hip dysplasia, follow the links on the next page.