Hip Replacement

Introduction

Hip replacements are extremely common (about 70,000 per year in the UK) and become necessary if the hip joint becomes damaged due to injury or disease, causing persistent pain.

This happens when the surfaces of the ball-and-socket joint between your thigh bone and pelvis bone are no longer smooth. The bones’ surfaces are rough and the cartilage lining has worn away.

Causes

The most common reason that people have hip replacement surgery is due to osteoarthritis in which the cartilage inside the hip joint becomes worn down and damaged.

Other conditions, such as rheumatoid arthritis (in which the body’s own immune system attacks the lining of the joint causing inflammation and damage), avascular necrosis (loss of bone caused by insufficient blood supply) andinjury of the hip joint, can also lead to damaged hip joints and the need for replacement surgery.

Surgical procedure

Hip replacement surgery usually takes up to two hours under a general anaesthetic (where you are asleep during the procedure) or an epidural (where the lower body is numbed).

The procedure involves Mr Hull making an incision overlying the hip, separating the muscles and ligaments to expose the joint. The damaged hip joint is then removed and any damaged bone or cartilage taken out and bones reshaped to prepare for the artificial socket to be attached using cement or other techniques. The artificial hip consists of a ball on a stem, and a socket. The stem is fixed into your thigh bone, and the new socket into the space in your pelvis.

The skin is then closed with stitches or clips.

Materials

Artificial hip joints are made out of either a metal alloy or in some cases, ceramic. Advances in materials used mean that the new hip joints are stronger, move more easily and last longer.

There has been recent media attention regarding metal on metal hip replacements.  Mr Hull has NEVER performed a metal on metal hip replacement.

Most of the time the bearing surface is metal on polyethylene (a specialist form of plastic).  In younger patients a ceramic bearing surface may be used.

Mr Hull always uses a cemented Exeter stem, and either a cemented Exeter cup, or uncemented Trilogy cup.  These implants are chosen due to their long term safety record and durability.  The latest data from the 2012 National Joint Registry confirms the chance of these having to redone within 7 years of the initial opertation is less than 2% , some of the best possible results - Download report

Risks and complications

As with all operations, there is a possibility of a reaction to the anaesthetic, excessive bleeding, developing a blood clot and wound infection. A general anaesthetic may also make you feel temporarily sick after the operation.

Specific complications of hip replacement are uncommon, but can include infection (you will be given antibiotics during and after surgery to help prevent this).  Deep joint infection is a serious but rare complication (less than 1:100 cases), it may necessitate a number of further operations to cure.

Joint dislocation is another possibility and is most likely to happen in the 1st few months after surgery and will need a minor operation to correct. The hip joint may also become loose, also requiring further surgery amend.

It’s also possible that tiny cracks can occur in your bone when Mr Hull fits the new joint. These usually heal, but sometimes your bone can fracture and require further surgery. You may also experience some numbness around your scar due to nerve damage and rarely the sciatic nerve may be stretched which could leave weakness in the foot, although this is usually temporary.

Another possibility is that your leg will become slightly shorter or longer, in which case it will help to wear a raised shoe to correct your balance.

Most people who have this surgery are not affected by complications but new hips will eventually wear out, especially in younger patients, after which time it may need to be replaced again.

Preparing for surgery

Mr Hull will talk to you about how best to prepare for surgery which may include stopping taking any anti-inflammatory medications such as aspirin to reduce the risk of blood clots and stopping smoking if you are a smoker to minimize the risk of infection.

If you're having a general anaesthetic, you will be asked to follow fasting instructions. This means not eating or drinking, typically for about six hours beforehand.

Mr Hull may also ask you to wear compression stockings to help prevent blood clots forming in the veins in your legs.

Recovery

After the operation, you will need to rest until the effects of the anaesthetic have worn off. You may not be able to feel or move your legs for several hours after a spinal or epidural anaesthetic.

A special pillow may be placed between your legs to hold your hip joint still and stop it from dislocating and you may need some pain relief to help with any discomfort. It is also likely that we will give you an injection into your abdomen to help prevent blood clots forming in your legs, and possibly a short course of antibiotics to help prevent infection.

Physical therapy starts soon after the operation, usually on the same day. This may start with a few exercises whilst in a chair, progressing to stepping, walking and climbing. Once you are able to walk safely with the aid of sticks or crutches, which is typically within about three to five days, you will be ready to go home.

Initially, you will feel discomfort while walking and exercising, and your legs and feet may be swollen. You can continue to take over-the-counter painkillers such as paracetamol or ibuprofen for relief.

You will be required to have blood thinning injections for a month following surgery to decrease your chances of developing blood clots.

Most patients are delighted with the results of a hip replacement, and feel a near immediate relief from their groin pain, and are back to walking without any aids within 1-2 months.

Further information

For further information please contact Mr Peter Hull FRCS, Consultant Trauma & Orthopaedic Surgeon