What is a Total Hip Replacement (THR)?
The hip joint is a ball and socket joint between the socket in the pelvis called acetabulum and the head of the femur bone.
In this procedure both the parts of the hip joint namely the upper part of femur and the acetabulum (weight bearing socket in the pelvis) are replaced by prosthetic devices made of metal, plastic or other biocompatible materials.
The stem of the prosthesis is made of Vitallium, forged Titanium alloy and stainless steel along with a lot of other substances. The acetabular component can be made of metal and plastic.
THR procedure reduces pain and improves mobility. But they are not as strong or long lasting as a normal, healthy hip joint.
Types of Total Hip Replacement
Broadly there are 2 types of Total Hip Replacement:
1. Cemented Total Hip Replacement ( Bone Cement Used)
2. Un-Cemented Total Hip Replacement
Why do we need a Total Hip Replacement?
Some of the reasons are
1. Severe arthritis( rheumatoid arthritis or osteoarthritis) leading to constant pain present all the time not relieved by painkillers, affecting quality of life and reducing mobility. Arthritis means wearing away of cartilage at bony ends.
2. Displaced intra-capsular fracture of the neck of femur in a fit and active person usually above the age of 60 years.
3. Non-inflammatory degenerative joint disease like avascular necrosis
4. As a second procedure for treating complications of hip fracture which were initially treated by some other procedure like screw fixation.
5. To treat reactive arthritis in young people after traumatic injury to the hip.
What are the conditions in which THR should not be performed?
Conditions where THR should not be performed are:
1. Infection in the hip joint
2. Infection elsewhere in the body which can be carried through the blood stream to the hip joint at a later stage.
3. Patients who may not be complaint with post operative instructions due to mental diseases, severe dementia, frequent fallers as they are at a higher risk of complications and dislocations.
4. Severe osteoporosis and obesity may cause an increased risk of failure.
What are the factors affecting a successful outcome post THR?
Success post THR depends on:
1. Body weight of the patient: An overweight patient’s THR may not last as long due to increased wear and tear.
2. Patient’s activity levels and profession: Excessive physical activity can reduce the life of the prosthesis by increasing wear and tear.
3. Substance abuse, smoking or mental illness: They are associated with a higher complication rate.
4. Taking appropriate precautions life long to prevent dislocations.
5. Reasonable level of physical activity is desirable.
Now read about the Complications of Total Hip Replacement