Total hip replacement

Total hip replacement is surgery that removes the damaged ball and socket of the hip and replaces them with implants. A stem placed inside the thighbone carries a new ball, which moves within a new socket lined with a smooth bearing surface. It is most often done for arthritis pain that has not responded to other treatment.

Hip replacement is considered for the symptoms of a badly damaged hip, not for an X-ray finding alone. It may be worth discussing when you have:

• Hip or groin pain that limits walking, bending, or climbing stairs
• Pain that continues at rest or wakes you at night
• Stiffness that makes it hard to lift the leg or put on shoes and socks
• Too little relief from medication, physical therapy, activity changes, or a walking aid

The most common reason for hip replacement is osteoarthritis. Other conditions that can damage the joint include rheumatoid and other inflammatory arthritis, osteonecrosis (loss of blood supply to the ball of the hip), arthritis after an injury, hip problems that began in childhood, and some fractures of the upper thighbone, particularly in older adults.

The evaluation includes a review of your health history and how the hip affects daily life, an examination of hip motion, strength, and leg length, and X-rays. An MRI is occasionally needed.

Before surgery you will usually have a medical checkup and routine tests. Your care team will review your medications, including blood thinners and medicines that affect the immune system, and may ask you to stop smoking, bring blood sugar under control, and finish any needed dental work. Arranging a walker or cane, help at home, and a safe, uncluttered living space ahead of time makes the first weeks easier.

Hip replacement is generally recommended only after non-surgical care — exercise and physical therapy, activity changes, weight management when appropriate, medications, a walking aid, and sometimes injections — no longer controls pain and stiffness.

The operation is done under general or regional (spinal) anesthesia. The surgeon removes the worn ball and the damaged surface of the socket. A metal cup is placed in the socket with a liner of plastic, ceramic, or metal, and a stem is fitted into the thighbone, carrying a metal or ceramic ball. The implants are either held with bone cement or press-fit so the bone grows onto them.

The hip can be reached from the back, the side, or the front. Each approach has trade-offs, and your surgeon will explain the one recommended for you.

As with any surgery, there are risks. They include infection, blood clots, dislocation of the new hip, a difference in leg length, fracture or nerve injury during surgery, and, over many years, loosening or wear of the implant that may need further surgery.

Many people go home the same day or after a short hospital stay; some spend time in a rehabilitation facility first. Walking with a walker or crutches usually begins on the day of surgery or the next day, supported by blood clot prevention, pain control that combines several types of medication, and a home exercise program.

Recovery generally involves a gradual return to walking and light daily activities over the following weeks, with strength and endurance continuing to improve for months. Your surgeon may give you positions to avoid for a period to protect the new hip.

Over the long term, low-impact activities such as walking, swimming, cycling, golf, and dancing are generally encouraged, while running and jumping are usually discouraged because they increase wear. Periodic follow-up visits with X-rays help track the implant over time.

Steps that help protect a new hip:

• Follow the movement precautions and exercise program you are given
• Use your walking aid until your care team says it is safe to stop, and clear tripping hazards at home
• Take blood clot prevention medication as prescribed
• Keep the incision clean and dry until it has healed
• Tell your dentist and other clinicians that you have a joint replacement, and ask your surgeon whether you need antibiotics before dental work
• Keep a healthy weight and stay active with low-impact exercise