Hip replacement surgery FAQs

Every year over 100,000 hip replacement surgeries are performed in the UK. The majority are carried out to treat hip osteoarthritis. Here, we’ll look at what to expect from hip replacement surgery, how to prepare and what recovery involves. 

Why might you need a hip replacement?

Hip osteoarthritis is the most common reason for needing hip replacement surgery. However, you may also need a hip replacement to treat damage to your hip joint caused by inflammatory arthritis, such as rheumatoid arthritis, psoriatic arthritis or systemic lupus erythematosus, or post-traumatic hip arthritis due to a past injury. 

Less common causes for needing a hip replacement include conditions affecting the hip joint that occur in childhood or from birth and cause problems in adulthood. This includes Perthes’ disease where the head of the thigh bone (femur) deteriorates due to poor blood supply, hip dysplasia where the hip socket is too shallow, and femoroacetabular impingement (FAI) where the anatomy of the ball-and-socket joint of the hip prevents it fitting together properly. 

What happens to the hip joint in hip arthritis?

Your hip joint is a ball-and-socket joint, where the ball is formed by the head of your thigh bone (femur) and the socket is formed by a part of your pelvis called the acetabulum. The surfaces of both the ball and socket are lined with cartilage and the joint is lubricated by synovial fluid — together this allows smooth movement of your hip joint. 

Hip arthritis causes the cartilage to wear away and reduces the amount of synovial fluid produced. Consequently, the bony surfaces of the ball and socket rub together, causing joint pain. Hip replacement surgery aims to relieve this pain by replacing the hip joint.

What are the different types of hip replacement surgery?

Hip replacement surgery replaces the damaged parts of your hip joint. Both the ball part of your joint (the head of your femur) and the socket part of your joint (the acetabulum of your pelvis) can be replaced with artificial parts. The artificial ball is attached to a stem inserted into the top of your femur.

Hip joint materials

Hip replacements can be grouped according to the type of material that is used for the artificial parts, which are known as bearing surfaces. 

There are four main types: a metal ball with a plastic socket, a ceramic ball with a plastic socket, a ceramic ball with a ceramic liner on the socket, and a metal ball with a metal socket. 

Metal-on-metal hip replacements can produce small metal particles that wear off due to friction as the metal ball and socket rub against each other. This can cause irritation and swelling, which is why this type of hip replacement is not commonly used today.

In addition to the choice of material for these artificial parts, there is also the option of whether the replacement parts are cemented into place, uncemented or a combination where one part is cemented and the other part is not. Uncemented parts are specially designed to be secured in place without cement. 

Type of surgery

Hip replacements can also be grouped according to how the surgery is performed, specifically how the hip joint is exposed. 

The most common type is posterior hip replacement surgery where a cut is made at the back of the hip. Other approaches include anterolateral hip replacement surgery where the cut is made on the side of the hip and anterior hip replacement surgery where the cut is made in the front of the hip.

Hip replacements can also be performed as traditional surgery, where a large cut is made, or as minimally invasive surgery, where one or two small cuts are made. Minimally invasive surgery is not appropriate for everyone.

Which type of hip replacement surgery is best?

The type of hip replacement surgery that is suitable for you will depend on your age, how active you are and the health of your bones (eg if you have brittle bones (osteoporosis)). 

If you lead an active lifestyle and/or are younger, then greater demands will be placed on your artificial joint. Your surgeon may, therefore, recommend more advanced bearing surfaces, such as a ceramic ball with a plastic socket or a ceramic liner on your socket.

If the quality of your bones is not ideal, your surgeon may recommend fixing your artificial joint in place using cement. 

How should you prepare for hip replacement surgery?

It is important to prepare for your surgery by learning about what will be involved so you know what to expect. Your surgeon will explain the procedure to you and your care team can provide you with leaflets and direct you to other sources of information. 

Before your surgery, regular exercise to build up your muscle strength can help speed up your recovery after surgery. Losing any excess weight and quitting smoking can also aid your recovery and healing, and reduce the risk of complications during your surgery. 

It is also important to prepare your home for your recovery period eg removing trip hazards, placing items you use regularly within easy reach and stocking up on pre-prepared meals. Your care team will advise you about walking aids.  

You may need to stop taking certain medications (eg blood thinners) in the run-up to your surgery; make sure you tell your care team about any medications and supplements you are taking so they can advise you on what to do. 

What does recovery involve after hip replacement surgery?

Recovery in hospital

In most cases, you will need to stay in hospital for one to two days after your surgery. If you develop any complications or are struggling to manage your pain, you may need to stay in hospital for longer. 

While in hospital, a physiotherapist will go through a range of exercises with you to help you get moving again as soon as possible. This will include getting out of bed independently, dressing yourself and walking with crutches. This will help ensure that you can take care of yourself when you return home. 

Recovery at home

When you are discharged from hospital, you will be prescribed painkillers for the first two to three weeks of your recovery. During this time, try to avoid sitting on very low chairs, crossing your legs and sleeping on your side. 

Your wound will have a dressing on it that can remain in place for about two weeks. During this time, you will need to keep your wound dry, so make sure you cover your dressing with plastic when showering and avoid bathing. 

After two weeks of recovery, a nurse in hospital or at your GP practice will remove your dressing and check how your wound is healing. You should still avoid having a bath for about a week after your dressing is removed. 

As your pain reduces and your body heals, your stamina and mobility will increase. You should be able to come off your crutches after six weeks and will have a follow-up appointment with your surgeon at around this time too. 

If you have a sedentary job, you can return to work after four to six weeks. If you have a physically demanding job, you will most likely need to wait until you have made a complete recovery, which usually takes around three months. 

You can return to driving when you can safely make an emergency stop. 

What are the potential complications of hip replacement surgery?

Hip replacement surgery is a major operation, but in the vast majority of cases (over 90%), it is successful in improving pain, mobility and quality of life. 

However, as with any surgery, there are risks, such as a bad reaction to the general anaesthetic, excessive bleeding, tissue damage and infection. 

The chances of infection are low at around one in 100. This risk is controlled through the preventive use of antibiotics and good wound care. Signs that your wound is infected include discharge seeping through your dressing, red skin around your wound, a fever and feeling unwell. If you notice these signs, contact your care team immediately. 

Hip replacement surgery also carries the risk of blood clots. This can result in a deep vein thrombosis (DVT) or pulmonary embolism (PE), which are both life-threatening. To reduce the risk of blood clots, you will be prescribed blood thinners to take for the first five weeks of your recovery. 

Signs of a DVT include swelling, tightness and/or increasing pain in your calf. If you notice these signs go straight to A&E or call 999. 

The risk of dislocation after hip replacement surgery is less than one in 100 but is highest during the first three months after surgery. It is, therefore, important to follow the advice of your surgeon and physiotherapist to reduce this risk.

The risk of nerve damage during hip replacement surgery is around one in 1,000. 

What are the outcomes of hip replacement surgery? 

Hip replacement surgery is successful in the vast majority of cases, with individuals able to return to leisure activities that they couldn’t enjoy prior to surgery, such as long walks and sports. 

Modern hip replacements last for 15–20 years before revision surgery is needed to address wear and tear, loosening and/or dislocation of the replacement hip joint.