Hip resurfacing an alternative to hip replacement surgery
Dear Doctors: My eldest brother has worked in construction all his life, and now he has severe arthritis in his left hip. He was in enough pain that he finally consulted his doctor about it. Instead of a hip replacement, they want to do a hip resurfacing. What is that? Will it be as effective?
Dear reader: Hip resurfacing is a type of hip replacement surgery.
The most common reason a person needs this type of surgery is advanced osteoarthritis. Also known as “wear and tear arthritis”, it is common in older people and in certain occupations.
Hip osteoarthritis can cause pain severe enough to limit mobility and interfere with daily activities.
The hip is a ball and socket joint, which allows the range of motion that we have in our legs. The rounded top of the femur, the largest bone in the leg, forms the ball. This is the femoral head. It fits into a cup-shaped socket in the pelvis, the acetabulum. The ball and socket are covered in smooth cartilage, allowing them to slide past each other painlessly.
With osteoarthritis, this cartilage gradually wears away, making movement painful.
When non-surgical approaches to managing osteoarthritis pain are not successful, hip replacement surgery is often recommended.
In a traditional hip replacement, the femoral head and acetabulum are removed, replaced with plastic, ceramic, and sometimes metal components.
With hip resurfacing, the damaged bone and cartilage of the femoral head and acetabulum are removed. The surgeon then lines the socket with a metal shell and covers the femoral head with a smooth metal cap.
Benefits over total hip replacement include faster recovery, improved mobility, and reduced risk of hip dislocation. It is also easier to replace implants if they wear out or fail.
But there are downsides. One is the risk of femoral neck fracture, which occurs in a small number of hip resurfacing patients. This requires a full hip replacement. The other is called metal ion risk. Since hip resurfacing uses two metal components, the resulting friction can, over time, cause the release of tiny metal molecules that can cause pain and swelling, which may require further surgery.
Ions can also travel throughout the body via the bloodstream and have been linked to adverse effects on the heart, nervous system, thyroid, and cancer. Metal ion risk is a potential complication of traditional hip replacements that use a metal ball and metal socket.
Dr. Eve Glazier and Dr. Elizabeth Ko are internists at UCLA Health.