Hip Resurfacing

Please note that I no longer perform hip resurfacing surgery. There are a number of reasons for this:

• Risk cobalt and chrome metal ion toxicity as a result of wear of the metal on metal moving parts. This can result in local toxicity with destruction of soft tissue and bone as well as effects in the bloodstream which are not well understood. This does not occur with conventional hip replacement surgery which can be performed using different materials.
• The surgery requires a larger incision and cannot be performed through the anterior approach
• The risk of revision surgery is not reduced and is probably increased compared to conventional hip replacement surgery using the best performing implants (1)

The following is included for general information as I frequently get asked about this procedure.

Introduction

The hip joint is also known as a ball and socket joint, where the ball (femoral head) of the thigh bone fits into the socket (acetabulum) of the pelvis bone.

Damage to the hip bones can be treated by hip resurfacing, which is a surgical procedure in which the damaged parts of the femoral head are trimmed, and the socket is removed and replaced with metal caps.

Hip resurfacing is an alternative to total hip replacement surgery where both the ball and socket of the hip joint are completely removed and replaced metal, or ceramic prosthetics.

Indications and contraindications

Your Surgeon may recommend hip resurfacing surgery if you suffer from severe hip arthritis affecting your quality of life and the symptoms have not been relieved with conservative treatment options such as medications, injections, and physical therapy.

In addition, younger, larger-framed patients with strong and healthy bone are more suitable candidates for hip resurfacing surgery, although conventional hip replacement probably performs as well or better in this group also (1).

Hip resurfacing surgery is not recommended in patients with known metal hypersensitivities, osteoporosis, diabetes, impaired kidney function, and large areas of dead bone (avascular necrosis).

Surgical procedure

Hip resurfacing surgery is performed with the patient under spinal or general anesthesia.

Your surgeon makes an incision over your thigh to locate the hip joint. The femoral head is displaced from its socket, trimmed of the damage using special instruments, and fitted with a metal cap. The damaged bone and cartilage lining the socket is removed and a metal cup is fixed. Finally, the femoral head is repositioned into the socket, and the incision is closed.

Advantages of hip resurfacing

The purported advantages of hip resurfacing over total hip replacement include:

• Easier to revise: Components used in both procedures can wear out, loosen or fail after a period of 10 to 20 years, requiring revision surgery. As hip resurfacing involves less removal of bone from the femur, the revision surgery can sometimes be easier to perform.
• Lower risk of hip dislocation: As the ball size in hip resurfacing is larger and closer to the normal size, the risk of hip dislocation is less.
• Greater range of hip motion

Disadvantages of hip resurfacing

The disadvantages of hip resurfacing are:

• Femoral neck fracture: There is a likelihood of femoral neck fracture with hip resurfacing, which eventually necessitates a total hip replacement.
• Metal ion risk: Tiny metal particles or ions produced by the movement of the metal ball against the metal socket may produce an allergic reaction causing pain and swelling.
• Difficulty: Hip resurfacing is a more difficult procedure to perform, requiring a larger incision.

Risks and complications

As with any surgery, complications are rare but can occur. Hip resurfacing patients may have complications including:

• Formation of blood clots in the leg veins
• Injury to nerves or blood vessels
• Infection
• Femoral neck fracture
• Dislocation

Reference:

1. The Birmingham hip resurfacing (BHR) does not have a lower revision rate than the best conventional total hip replacements (THR) in men under the age of 65 in the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR)

J. Stoney, S. Graves, R. d. Steiger and L. Kelly

AOA & NZOA ASM proceedings, 9-13 October 2016, Cairns, Queensland.