Orthopaedic Surgery - Hip Hemi-arthroplasty

Procedure

The hip joint is a “ball and socket joint.” It is a very important joint as it allows a great deal of movement but is also weight- bearing. Your hip is broken, and your surgeons recommend it is replaced. In this operation, the ball is replaced, but the cup remains your own bone (this is why it is called a “hemi” [meaning a half] hip operation).

You will be visited by your surgeon before the operation. If you have any questions, now might be a good time to ask them. The surgeon will mark on your leg with a felt pen. This is to make sure the correct leg is operated on.

An anaesthetic will be given in theatres. This may be a general anaesthetic (where you will be asleep) and/ or a regional block (e.g. where you are awake but the area to be operated is completely numbed) for example an injection into the spine.

You must discuss this and the risks with the anaesthetist. If you have any allergies, please also tell them.

You will lie on the opposite side to the one being operated on. Your skin will be cleaned with antiseptic fluid and clean towels (drapes) will be wrapped around the hip.

The surgeon will make a cut (incision) using a surgical knife (scalpel). The exact location of the incision depends on your surgeon’s technique. The length of the incision also depends upon the surgeon and your leg.
 
A cut is made through the fat and muscles which lie in the way of the hip bones. The top of the thigh bone (femur) which forms the neck and ball will be cut away. A replacement stem and ball can then be placed in the remaining thigh bone.

When satisfied with the positions, the surgeon will close the wound. A drain may be used. This allows any collections of blood or fluid to drain out. The drain can be removed painlessly on the ward within a day or two.

The skin can finally be closed. Some surgeons use stitches, while others prefer metal clips (skin staples). Both methods are equally successful and come down to surgeon preference.

When you wake up, you will feel sore around the hip, this is normal. You will be encouraged to start walking as soon as possible with the aid of the physiotherapists.

An x-ray and a blood test may be taken the next day.

Please be aware that a surgeon other than the consultant, but with adequate training or supervision may perform the operation.

Alternative procedure

There may be other options to fix your broken hip. However, your surgeon’s experience tells them a half-hip replacement is the best option.

There are options of half hip you can consider - you should discuss these with your surgeon.

Risks

As with all procedures this carries some risks and complications.

Common (2-5%)

Blood clots

A DVT (deep vein thrombosis) is a blood clot in a vein. These may present as red, painful and swollen legs (usually). The risks of a DVT are greater after any surgery (and especially bone surgery). Although not a problem themselves, a DVT can pass in the blood stream and be deposited in the lungs (a pulmonary embolism - PE). See later. This is a very serious condition which affects your breathing. Your doctors may give you medication through a needle to try and limit this risk of DVTs from forming. Some centres will also ask you to wear stockings on your legs, while others may use foot pumps to keep blood circulating around the leg. Starting to walk and getting moving is one of the best ways to prevent blood clots from forming.

Bleeding

This is usually small and can be stopped in the operation. However, large amounts of bleeding may need a blood transfusion or iron tablets. Rarely, the bleeding may form a blood clot or large bruise within the wound which may become painful and require an operation to remove it.

Pain

The hip will be sore after the operation. If you are in pain, it is important to tell staff so that medicines can be given. Pain will improve with time. Rarely, pain will be a long term problem. This may be due to altered leg length or any of the other complications listed below, or sometimes, for no obvious reason.

Altered leg length

The leg which has been operated upon, may appear shorter or longer than the other. This rarely requires a further operation to correct the difference or shoe implants.

Joint dislocation

If this occurs, the joint can usually be put back into place without the need for surgery. Sometimes this is not possible, and an operation is required, followed by application of a hip brace or rarely if the hip keeps dislocating, a revision operation may be necessary.

Less Common (1-2%)

Infection

You will be given antibiotics just before and after the operation and the procedure will also be performed in sterile conditions (theatre) with sterile equipment. Despite this there are still infections (1 to 2½%). The wound site may become red, hot and painful. There may also be a discharge of fluid or pus. This is usually treated with antibiotics, but an operation to washout the joint may be necessary. In rare cases, the implants may be removed and replaced at a later date. The infection can sometimes lead to sepsis (blood infection) and strong antibiotics are required.

Rare (<1%)

Altered wound healing

The wound may become red, thickened and painful (keloid scar) especially in AfroCaribbean people. Massaging the scar with cream when it has healed may help.

Nerve damage

Efforts are made to prevent this, however, damage to the nerves around the hip is a risk. This may cause temporary or permanent altered sensation along the leg. In particular, there may be damage to the Sciatic Nerve, this may cause temporary or permanent weakness or altered sensation of the leg.

Bone damage

The thigh bone may be broken when the implant (metal replacement) is put in. This may require fixation, either at time or at a later operation.

Blood vessel damage

The vessels around the hip may rarely be damaged. This may require further surgery by the vascular surgeons.

Pulmonary embolism

A PE is a consequence of a DVT. It is a blood clot that spreads to the lungs and can make breathing very difficult. A PE can be fatal.

Death

This rare complication can occur from any of the above complications.