What Is a Hip Replacement?

If a hip has become stiff and painful enough that walking to the shops, climbing stairs, or sleeping through the night is a struggle, you may hear a hip replacement mentioned. But what does "replacing" a hip actually mean — and how much of what people say about it is true? The short answer is that the worn parts of the joint are removed and replaced with smooth artificial parts. The video at the top of this page is an animation of a total hip replacement, which makes it a useful way to see how those parts fit together before reading on — no live surgery, just the mechanics of the new joint, step by step.

First, how a healthy hip works

Your hip is a ball-and-socket joint. The ball is the rounded top of your thighbone, and it sits in a cup-shaped socket in your pelvis. Healthy cartilage covers both surfaces, so the ball glides smoothly as you walk, sit, and turn. When that cartilage wears away — most often through osteoarthritis — bone can rub on bone, and movement becomes painful and restricted. A replacement does not repair the cartilage; it replaces the damaged surfaces themselves.

Myth: the whole hip bone is taken out

It isn't. During the operation, the surgeon removes the damaged ball at the top of the thighbone and reshapes the worn socket. A metal stem is then fitted into the thighbone with a new ball on top, and a cup is fixed into the pelvis socket, usually with a smooth lining inside it. Together, those components form a new ball-and-socket joint designed to move with less friction. For a longer explainer that weighs up the benefits and the limitations in more depth, this site's "Total Hip Replacement" video is worth watching alongside the animation. The operation is done with anaesthesia, and the exact approach varies — your surgeon can explain the plan in your case.

Myth: it is only an operation for older people

Age alone doesn't decide this. What tends to matter more is how much pain and loss of movement you have, how the joint looks on examination and imaging, what else has already been tried, and your general health. Replacement is usually considered when pain lingers despite simpler measures and is interfering with everyday life — not as a first step for a new ache. Younger, active people can be considered too, though the conversation about activity and the long-term life of the implant may be different for them. That judgement belongs to you and your orthopaedic team together, not to an article.

Myth: you will be back to normal in a few days

Recovery is real work, and it is measured in weeks and months rather than days. Most people begin moving and walking with support soon after surgery, guided by the hospital team, and physiotherapy exercises continue at home to rebuild strength and flexibility. It is common to need a walking aid for a while, and to build up distance and confidence gradually. Like any operation, hip replacement also carries risks — including infection, blood clots, and the new ball slipping out of position — which your team will discuss with you beforehand, along with the precautions that lower them. If knees rather than hips are your concern, our guide to knee replacement explains how that related joint operation works.

Myth: after surgery, you should protect the hip by barely moving it

Actually, movement is part of the treatment. The new joint and the muscles around it recover best when they are used, within the guidance your surgeon and physiotherapist give you. Some positions or movements may be limited for a period, depending on the surgical approach, but the general direction is toward more activity, not less — regular walking and the prescribed exercises are what turn a successful operation into a hip that genuinely feels better in daily life.

MedicalVideos.com has published trusted medical videos since 2007. The site was founded by Dr. Mohamed Ibrahim, MD, PhD — physician and researcher.

Frequently Asked Questions

Is a hip replacement the same as a total hip replacement?
Usually, yes — "total" means both sides of the joint are replaced: the ball at the top of the thighbone and the socket in the pelvis. The animation at the top of this page shows a total replacement.

What is the new hip made of?
The components are typically made from metal, with a smooth lining of plastic or ceramic where the ball meets the cup, so the surfaces glide against each other. Your surgeon chooses the materials used in your case.

Will I need physiotherapy afterwards?
Yes, in most cases. Exercises to restore movement and rebuild muscle strength are a standard part of recovery, starting in hospital and continuing at home.

Can both hips be replaced?
If both hips are badly worn, they can be replaced in separate operations, and occasionally the timing is planned together. Whether and when to do the second side is a decision for you and your surgeon.

Does a hip replacement cure arthritis elsewhere?
No. It treats the replaced joint only. Arthritis in other joints, such as the other hip or the knees, is assessed and managed separately.

Educational only — this article is general information about hip replacement, not medical advice and not a recommendation for or against surgery. Whether a hip replacement is appropriate for you is a decision for your own doctor and orthopaedic surgeon, who can examine you and review your imaging.