REVISION HIP REPLACEMENT

A Guide for Patients

The Basford Consulting Rooms has a number of Orthopaedic Surgeons who specialise in Revision Hip Replacement Surgery. 

Introduction

This booklet provides information for you and your family regarding total hip replacement. Your Consultant may recommend a total hip replacement for you, but the decision to have the operation is yours. Your decision must be based upon weighing the benefits against any risks. If you have any questions as you read through this booklet then ask the doctor, nurse or therapist at your next visit. You may find it helpful to make a note of your questions before you see the doctor or nurse.

It may be helpful to read our booklet ‘TOTAL HIP REPLACEMENT - a Guide for Patients’ for more information on hip replacements and revisit the ‘do’s and don’ts’.

Most hip replacements last for more than ten years.

Indications for Revisional Surgery

*  Loosening – This is when the fixation or anchorage of the prosthesis in the bone fails. This could be related to infection or unrelated to infection. Loosening is 
    usually associated with pain but can be asymptomatic and only identified from X-Rays.

 

*  Osteolysis – This is when a cavity forms close to the cement or prosthesis coating. This can weaken the bone to an extent that a fracture or loosening can occur.

 

*  Excessive Wear – This usually occurs on the socket side, especially if the socket is made polyethylene.

 

*  Implant Breakage or Displacement – An implant can break if excessive stress is placed upon it. It is uncommon now, as the materials used are very strong. However, 
    this can occur.

 

*  Dislocation – The hip joint itself may become detached. If this occurs it is usually replaced under an anaesthetic. Occasionally the dislocation can be quite often. The 
    reasons for this are multifactorial and require discussion with the surgeon. Dislocation can also occur due to excessive wear.

 

*  Infection – Infection, in the long term, can result in loosening. Pain and general illness or a discharging wound can be present in a well fixed joint. This will necessitate 
    a revision.

Techniques utilised will vary, depending upon the extent of bone loss and weakening, or whether it is the acetabular component (hip socket) or the femoral component (stem) that has failed.

Revisional Surgery for Infection

Established infection results in pain, systemic illness or chronic discharge. This usually requires complete removal of all implant material. It is followed by an intense period of intravenous antibiotic administration and an antibiotic loaded spacer of some description.

After a period of time when the infected markers in the blood has lowered, the new hip is inserted. Surgery is about 80% successful depending on the type of infection.

Loosening on the Socket Site

The most usual revision is a non-cemented socket fixed by a bony ingot into the roughened surface of the cup. A tight fit in the bone can be supplemented with screws. Cement does not work too well where there is little or no cancellous bone.

If there is significant loss of bone from the acetabulum, then a metallic ring is required for structural support. Bone grafts can also be used to fill any defect and to regenerate more bone. A special steel mesh cage is frequently used to hold a graft in place. The component can be either cemented or uncemented.

Problems on the Femoral side

The revision can be performed by removing old cement and reinserting new cement sometimes, with a slightly longer component to allow for better fixation. If the bone is very thin, this can be supported with compacted particles of donor bone and a new femoral component could be cemented in. If the defect is large, then the defect is built up with mesh and bone graft and a longer prosthesis could be used.

If there is significant osteolysis or loss of bone proximally, then it may necessitate the use of the long component and fixation of this component, distal to the defect, in good bone.

Potential Complications of Revisional Surgery

Complications are similar to those of the primary hip replacement but the risk of complications is greater.

*  The infection rate is 1-3%. The treatment of infection in the original procedure is more difficult.

 

*  Dislocation is more common. We tend to use a large head to prevent this. 

 

*  Deep vein thrombosis and pulmonary embolisms are also more common.  Blood thinning agents are used but there is a risk of bleeding and other complications, and 
    this requires to be offset against the benefits of blood thinning.

 

*  Nerve weakness is more common and unpredictable at 2-3%.

 

*  Heavy bleeding may also cause concern perioperatively and, therefore, we would normally keep in reserve blood for use. If you are undertaking revisional hip 
    surgery then there is a high likelihood of you receiving a blood transfusion.

Certain medical complications are more common as patients requiring revisional surgery are generally older than those requiring primary hip replacements. The risk of complications will require discussion on an individual basis with your consultant surgeon.

Very often, revisional hip surgery is quite complex and unpredictable. The techniques required are complicated and the surgeon will very often “change tack” to deal with the problem. This could be changes in surgical technique or use of a different prosthesis to get the best results.

If there are special circumstances in the individual case, the surgeon will explain these before the operation.

General Observations

Surgery is best performed before severe bone loss occurs. The more bone loss the greater the complexity of the surgery. It must be noted that pain is not always a major feature in loosening, whilst pain is usually the major feature in a primary total hip replacement.

Any pain is likely to improve but strength of the hip may not return to normal. There may be a slight limp and walking aids may be required. This is because the muscles and attachments have been divided for a second time and reattachment and healing of the muscles can be more difficult.

If the bone is weakened considerably, surgery is advised in order to prevent a fracture. The risks of surgery in the presence of a fracture (periprosthetic fracture) are greater and surgery is likely to be performed as an emergency rather than in a planned way.

The results of the surgery also depend on the quality of bone and general health of the patient. In the presence of additional medical illnesses, the benefits of surgery should be