Total hip replacement: why it is done, how it works, recovery and risks

The hip is a ball-and-socket joint. Versus Arthritis explains that the ball is the femoral head at the top of the thigh bone, which rotates in a socket in the pelvis called the acetabulum. When the smooth cartilage lining wears away, the bones rub together and the joint becomes painful and stiff. The NHS describes hip replacement, sometimes called total hip replacement, as replacing damaged parts of the joint with metal, plastic or ceramic parts.

Most operations are total hip replacements with two components. Versus Arthritis describes a ball on a stem, which replaces the head of the thigh bone, and a bowl-shaped socket in the pelvis. The stem is always metal, and the ball and socket can be metal-on-plastic (the most widely used), ceramic-on-plastic or ceramic-on-ceramic. Parts are often fixed with acrylic cement, though uncemented fixation, where bone grows onto a roughened or coated surface, is becoming more common, and a hybrid uses cement for only one part.

The NHS says it can significantly improve daily life for people with hip pain and stiffness, but it can take several months to recover from surgery.

The NHS says a hip replacement may be recommended if hip pain and stiffness are having a big effect on your life and other treatments have not worked. Osteoarthritis is the commonest reason; rheumatoid arthritis and damage after a fall, injury or accident can also lead to it. NICE says people are usually offered joint replacement only after other treatments like pain medication, physiotherapy and lifestyle advice have not helped.

The NHS lists the usual alternatives to try first: weight loss if overweight, low-impact exercise such as swimming, walking or cycling with hip-strengthening, walking aids, special footwear or insoles, pain relief medicines, gels or creams, and steroid injections into the hip joint. Versus Arthritis adds that there are no upper or lower age limits, but replacement joints eventually wear out, so the younger you are, the more likely you are to need further surgery in future.

The NHS suggests muscle-strengthening exercises before and after surgery, losing weight if overweight, stopping smoking, healthy eating and keeping within weekly alcohol limits, noting these matter while you wait because waiting lists can be long and they may lower complication risk and speed recovery.

You will probably attend a pre-admission clinic a few weeks beforehand, where the NHS says you may have a blood test, X-rays, a urine test for infection or an ECG. Versus Arthritis says this is usually two to three weeks before surgery, that some hospitals run a joint school which research suggests leaves people less worried and doing better after surgery, and that a dental check-up beforehand is sensible because bacteria from dental problems could cause infection. Bring a list of your medicines and ask which, if any, to adjust.

Plan for home too: ask for help with day-to-day tasks, keep frequently used things within reach, stock the freezer, arrange transport since you cannot drive for at least 6 weeks, talk to your employer, and consider a raised toilet seat or a hand-held grabber.

The NHS says you usually go into hospital on the day, with either a spinal anaesthetic or a general anaesthetic, and a sedative may be offered with the spinal. The operation usually takes about 1 to 2 hours. Some operations use a minimally invasive approach with smaller cuts, which is not suitable for everybody. You will be asked whether you consent to your details being entered in the National Joint Registry, which monitors joint replacements to improve safety and outcomes.

After surgery you spend time in a recovery room with pain relief, and may have a drain in the hip. The NHS says nurses and physiotherapists help you start walking as soon as possible, using crutches or a walking frame at first. If you are generally fit and surgery went well, you can usually go home around 1 to 3 days later, once the wound is healing and you can get around safely. Stitches or clips usually come out after about 10 days and a follow-up is typically 6 to 12 weeks after surgery.

The NHS lists things to do: walk daily as far as comfortable, follow the physiotherapist's exercises, wait at least 6 weeks to drive, avoid sex for 6 to 8 weeks, return to work when ready (usually about 6 weeks, depending on the job) and avoid sitting still for long periods. Things to avoid include sitting with legs crossed, bending the hip more than 90 degrees, bending down to touch your feet, low chairs or toilet seats, jumping or sudden turns, and lifting heavy objects until told it is safe. Versus Arthritis says pain from the surgery itself should start to ease within the first two weeks, though some people have longer-term pain that may need further treatment.

The NHS calls hip replacement a common and safe procedure but lists risks: blood clots or DVT, which can sometimes travel to the lungs (compression stockings are likely to be given); wound infection, usually treated with antibiotics but needing further surgery if it reaches the joint; a small difference in leg length, which a raised heel can address; damage to nerves, blood vessels or ligaments, which is not common; and dislocation or wear, which can happen soon after surgery or many years later. Modern hip replacement joints are designed to last at least 15 years, and a worn or dislocated hip may need further surgery.

The NHS adds that older metal-on-metal implants can wear and cause health problems, so people with one should have regular check-ups. For an urgent GP appointment or NHS 111, the NHS lists throbbing or cramping pain in the hip or leg, a high temperature, oozing or pus from the wound, or worsening redness, swelling or pain. Call 999 or go to A&E if pain and swelling in the hip or leg come with difficulty breathing or chest pain, which could be a blood clot in the lungs.

On the NHS, a GP or physiotherapist usually refers you to an orthopaedic team once non-surgical treatment has failed, and you join a waiting list whose length varies by hospital. Use the wait to strengthen, lose weight if needed and stop smoking, as the NHS advises.

Private hip replacement can shorten the wait. Ask your surgeon which implant and fixation they propose and why, how many hip replacements they perform, what their revision and complication rates are, which rehabilitation is included, and who deals with problems after discharge. Joint replacement outcomes are tracked in the National Joint Registry, which you can ask about.