During hip replacement, a surgeon removes the damaged sections of your hip joint and replaces them with parts usually constructed of metal, ceramic and very hard plastic. This artificial joint (prosthesis) helps reduce pain and improve function.

Also called total hip arthroplasty, hip replacement surgery might be an option for you if your hip pain interferes with daily activities and nonsurgical treatments haven’t helped or are no longer effective. Arthritis damage is the most common reason to need hip replacement.

Conditions that can damage the hip joint, sometimes making hip replacement surgery necessary, include:

• Osteoarthritis. Commonly known as wear-and-tear arthritis, osteoarthritis damages the slick cartilage that covers the ends of bones and helps joints move smoothly.
• Rheumatoid arthritis. Caused by an overactive immune system, rheumatoid arthritis produces a type of inflammation that can erode cartilage and occasionally underlying bone, resulting in damaged and deformed joints.
• Osteonecrosis. If there isn’t enough blood supplied to the ball portion of the hip joint, such as might result from a dislocation or fracture, the bone might collapse and deform.

You might consider hip replacement if you have hip pain that:

• Persists, despite pain medication
• Worsens with walking, even with a cane or walker
• Interferes with your sleep
• Makes it difficult to get dressed
• Affects your ability to go up or down stairs
• Makes it difficult to rise from a seated position

Risks associated with hip replacement surgery can include:

• Blood clots. Clots can form in your leg veins after surgery. This can be dangerous because a piece of a clot can break off and travel to your lung, heart or, rarely, your brain. Your doctor may prescribe blood-thinning medications to reduce this risk.
• Infection. Infections can occur at the site of your incision and in the deeper tissue near your new hip. Most infections are treated with antibiotics, but a major infection near your prosthesis might require surgery to remove and replace the prosthesis.
• Fracture. During surgery, healthy portions of your hip joint might fracture. Sometimes the fractures are small enough to heal on their own, but larger fractures might need to be stabilized with wires, screws, and possibly a metal plate or bone grafts.
• Dislocation. Certain positions can cause the ball of your new joint to come out of the socket, particularly in the first few months after surgery. If the hip dislocates, your doctor might fit you with a brace to keep the hip in the correct position. If your hip keeps dislocating, surgery is often required to stabilize it.
• Change in leg length. Your surgeon takes steps to avoid the problem, but occasionally a new hip makes one leg longer or shorter than the other. Sometimes this is caused by a contracture of muscles around the hip. In this case, progressively strengthening and stretching those muscles might help. You’re not likely to notice, small differences in leg length after a few months.
• Loosening. Although this complication is rare with newer implants, your new joint might not become solidly fixed to your bone or might loosen over time, causing pain in your hip. Surgery might be needed to fix the problem.
• Nerve damage. Rarely, nerves in the area where the implant is placed can be injured. Nerve damage can cause numbness, weakness and pain.

Need for second hip replacement

Your prosthetic hip joint might wear out eventually, especially if you have hip replacement surgery when you’re relatively young and active. Then you might need a second hip replacement. However, new materials are making implants last longer.

Before surgery you’ll meet with your orthopedic surgeon for an exam. The surgeon will:

• Ask about your medical history and current medications
• Examine your hip, paying attention to the range of motion in your joint and the strength of the surrounding muscles
• Order blood tests, and an X-ray. An MRI is rarely needed

During this preoperative evaluation is a good time for you to ask questions about the procedure. Be sure to find out which medications you should avoid or continue to take in the week before surgery.

Because tobacco use can interfere with healing, stop using tobacco products for at least a month before surgery and for at least two months after surgery. If you need help to quit, talk to your doctor.

Don’t have dental work, including teeth cleaning, two weeks before surgery.

When you check in for your surgery, you’ll be asked to remove your clothes and put on a hospital gown. You’ll be given either a spinal block, which numbs the lower half of your body, or a general anesthetic.

Your surgeon might also give you a nerve block by injecting an anesthetic around nerves or in and around the joint to help block pain after your surgery.

During the procedure

The surgical procedure takes a few hours. To perform a hip replacement, your surgeon:

• Makes an incision over the front or side of your hip, through the layers of tissue
• Removes diseased and damaged bone and cartilage, leaving healthy bone intact
• Implants the prosthetic socket into your pelvic bone, to replace the damaged socket
• Replaces the round ball on the top of your femur with the prosthetic ball, which is attached to a stem that fits into your thighbone

Techniques for hip replacement are constantly evolving. Surgeons continue to develop less invasive surgical techniques, which might reduce recovery time and pain.

After the procedure

After surgery, you’ll be moved to a recovery area for a few hours while your anesthesia wears off. Medical staff will monitor your blood pressure, pulse, alertness, pain or comfort level, and your need for medications.

How long you stay after surgery depends on your individual needs. Many people can go home that same day. You’ll be asked to breathe deeply, cough or blow into a device to help keep fluid out of your lungs.

Blood clot prevention

After your surgery, you’ll be at increased risk of blood clots in your legs. Possible measures to prevent this complication include:

• Moving early. You’ll be encouraged to sit up and walk with crutches or a walker soon after surgery. This will likely happen the same day as your surgery or on the next day.
• Applying pressure. Both during and after surgery, you might wear elastic compression stockings or inflatable air sleeves similar to a blood pressure cuff on your lower legs. The pressure exerted by the inflated sleeves helps keep blood from pooling in the leg veins, reducing the chance that clots will form.
• Blood-thinning medication. Your surgeon might prescribe an injected or oral blood thinner after surgery. Depending on how soon you walk, how active you are and your overall risk of blood clots, you might need blood thinners for several weeks after surgery.

Physical therapy

A physical therapist might help you with exercises you can do in the hospital and at home to speed recovery.

Activity and exercise must be a regular part of your day to regain the use of your joint and muscles. Your physical therapist will recommend strengthening and mobility exercises and will help you learn how to use a walking aid, such as a walker, a cane or crutches. As therapy progresses, you’ll usually increase the weight you put on your leg until you’re able to walk without assistance.

Home recovery and follow-up care

Before you leave the hospital, you and your caregivers will get tips on caring for your new hip. For a smooth transition:

• Arrange to have a friend or relative prepare some meals for you
• Place everyday items at waist level, so you won’t have to bend down or reach up
• Consider making some modifications to your home, such as getting a raised toilet seat if you have an usually low toilet
• Put things you need, such as your phone, tissues, TV remote, medicine and books near the area where you’ll be spending most of your time during recovery

Six to 12 weeks after surgery, you’ll have a follow-up appointment with your surgeon to make sure your hip is healing properly. If recovery is progressing well, most people resume at least some version of their normal activities by this time. Further recovery with improving strength will often occur for six to 12 months.

Expect your new hip joint to reduce the pain you felt before your surgery and increase the range of motion in your joint. But don’t expect to do everything you could do before the hip became painful.

High-impact activities — such as running or playing basketball — might be too stressful on your artificial joint. But in time, you might be able to swim, play golf, hike or ride a bike comfortably.