Total hip replacement

What is total hip replacement?

Total hip replacement is an operation designed to replace a hip joint which has been damaged, usually by arthritis. The hip joint is a ball-and-socket joint - the ball is formed by the head of the thigh bone (femur), which fits into the socket (acetabulum).

A smooth and compressible substance known as gristle or articular cartilage coats the surfaces of these bones. Arthritis occurs when the articular cartilage wears away, exposing the underlying bone. This causes roughening and distortion of the joint, resulting in painful and restricted movement. A limp will often develop and the leg may become wasted and shortened.

The total hip replacement operation replaces the worn head of the femur with a stainless steel ball mounted on a stem, and relines the socket (acetabulum) with a cup made of a special plastic (polyethylene). These two components are usually fixed to the bone by a cement called 'methyl methacrylate'. In special cases, other types of prostheses may be used.

The new joint relieves pain, decreases stiffness and, in most cases, restores leg length and corrects the limp.

Before surgery

Your surgeon may arrange for blood tests and other tests, and refer you to another specialist for pre-operative assessments. At this stage the following referrals are recommended:

• An occupational therapist for prescription of specific aids to enable you to perform daily activities more easily, and
• A physiotherapist for a home exercise programme and walking aids.

The home exercise programme before admission to hospital will assist you considerably in your recovery during the post-operative period. The exercise programme includes breathing and leg exercises and will be explained to you when you attend the physiotherapy assessment.

You will be admitted to hospital one day before the operation to allow for blood tests, anaesthetic assessment and shaving of the area to be operated. You will not be allowed to eat or drink for a number of hours prior to the operation.

Injections are given before and after the operation to thin the blood and reduce the risk of blood clot formation (thrombosis). A tube will be inserted into a vein during the operation to replace lost fluids, and for administering antibiotics.

A general or spinal anaesthetic may be used, depending on the individual case.

After surgery

After this operation you must lie on your back with a triangular pillow placed between your legs to keep them apart. This and other precautions are necessary to prevent harmful movements causing undue stress to your replaced hip, and to ensure that the hip remains in the correct position. Movement of your leg that was operated on, is, however an important part of the recovery programme and you will receive relevant instructions from the physiotherapist.

You will be able to assist the nursing staff to move you in bed by using the overhead bar. In particular, lifting your buttocks off the bed is important to enable pressure care and the use of bedpans, as you cannot go to a toilet until six days after the operation.

You will only be allowed to sit up to an angle of 45° in bed supported by three pillows. Twice a day it will be necessary to lie completely flat for one hour to stretch the muscles over the front of the hip.

When you have regained sufficient control of the leg that was operated on - usually after three to five days - the physiotherapist will help you to stand beside the bed, with the support of a walking frame.

You must always get in and out of bed on the same side as the leg that was operated on. Remember to keep your legs well apart and lean back to avoid excessive bending. Do not sit on the edge of the bed. Once the effected leg touches the floor, bend it well back and push down through your hands on the bed to stand up straight. Keep the leg out in front until you are standing. You will be assisted if necessary. Please practise this procedure before the operation.

Walking

Once you are accustomed to standing and have regained your balance, you will begin walking, using a frame to ease the weight on your new hip. The sequence is always to move the walking aid forward first, then the leg that was operated on, and finally the good leg.

Turning around should be towards your good side to prevent twisting or pivoting on your new hip. As your confidence and leg control improve, you will progress to walking with crutches and will practise with these until you achieve a satisfactory walking pattern. Some patients manage to walk with only two sticks by the time of their discharge.

Stairs

You will be taught how to negotiate steps with the use of walking aids:

• Going up steps - good leg first, then the leg that was operated on and lastly crutches.
• Going down steps - crutches first, then the leg that was operated on and lastly the good leg.

Six days after the operation you will commence sitting in a firm, high chair with arms, and will be taught how to sit safely. You must keep your back straight and lean back, not forward. The same posture should be maintained when using a toilet.

The physiotherapist will see you before the operation and during your stay in hospital to assess your ability to manage safely and independently at home, and to provide the necessary walking aids and advice. You will also be provided with additional information to take home with you.

After the operation you may temporarily need to alter the way in which you perform some daily activities and may require assistance from other people.

On discharge you may go home to friends or relatives, or to another hospital for further rehabilitation. This decision will be made by you, in conjunction with your medical advisers and therapists. The decision will depend on your home situation, the amount of assistance at home, your rate of progress and your physical condition.

You should not return home alone on discharge from hospital as you will need help to manage daily activities. You may also benefit from having permanent aids installed in your home.

Aftercare

Your diseased joint has been replaced with a new one made from synthetic materials. It is designed to remain in your body indefinitely, enabling you to live a fairly normal life.

Risks

If you get sepsis in your body, germs may spread through the bloodstream to infect the artificial joint. You should consult your doctor if you develop any of the following:

• Throat infection.
• Tooth abscess or tooth extraction.
• Boils.
• Infected cuts or sores.
• Chest infections, e.g. bronchitis.
• Urinary infection.

Remember

The post-operative physiotherapy is designed to be phased out as you leave hospital. Continue using your crutches as instructed, usually for two to three months.

• Do not force any movement.
• Do not lie on either side for two months unless you were taught how to do so with the use of pillows.
• Do not roll over in bed.
• Do not cross your legs or ankles.
• Going up stairs - good leg first.
• Going down stairs - crutches first, followed by the leg that was operated on.

Notes for daily activities

• Get into and out of bed on the side of the leg that was operated on, facing the foot of the bed as shown to you by the physiotherapist. Remember not to bend your hip beyond 60° or to cross your legs.
• Only sit on a firm, high chair with arm rests. Do not use your crutches to get up, rather grasp the arms of the chair or the side of a table. Place the leg that was operated on forward and use your good leg as support to raise your body to an upright position. Do the same when sitting down.
• Car travel is not permitted until six weeks after the operation, other than in exceptional circumstances. Thereafter getting into and out of the car depends on your height, the length of your leg and the spaciousness of the car. The safest method is to get in backwards and sit across the seat in a reclining position as shown to you by the physiotherapist.
• Do not attempt to put on trousers, pants, stockings or socks without assistance from someone or without using an aid. Do not put on your shoes or tie shoelaces without help. Preferably use slip-on shoes, as you do not have to bend to put them on - a long-handled shoehorn can be used to make this task easier.

Do not

For two months following surgery you should not:

• Sit upright in bed with your legs straight on the bed, either propping yourself up with pillows or on straight arms.
• Sit in a low chair, such as a lounge chair - remember your hip must be higher than your knee.
• Have a bath. Rather sit on a high chair in a stand-up shower or next to the basin. Avoid bending your hip by using a long-handled brush to wash your foot and leg. Also do not bend your hip when drying yourself.
• Use a normal toilet. Use a raised toilet seat or equivalent.
• Drive.
• Run, jump, climb, carry heavy objects, dig in the garden, or sail.
• Have sexual intercourse.

The above precautions should be followed for two months, or as instructed by your surgeon. After this period, gradually reintroduce your hip to the normal range of movements and revert back to your usual daily activities. Do not worry if the degree of movement does not improve immediately, it will improve gradually during the year.

Do seek advice from your surgeon or physiotherapist before you consider taking up sport or a physically demanding job.