Total Hip Replacement Introduction
The hip is a “ball and socket” joint. The ball is formed by the head of the thigh bone (femur) which fits snugly into the cup-shaped bone in the pelvis (acetabulum).
The bones are coated with cartilage, which acts as a cushion between the two bones and allows movement.
The aim of total hip replacement is to relieve pain and improve movement. Total hip replacements are usually performed for people with arthritis which gets worse and no longer responds to other treatments. The most common type of arthritis is osteo – arthritis, which happens with aging, congenital abnormality of the hip joint, or previous injury to the hip joint.
What is Total Hip Arthroplasty?
A total hip replacement removes the damaged areas of the bone and is replaced with prosthetic components. The head of the femur is replaced with an artificial ball and stem which fits into the thigh bone. The socket is replaced with an artificial cup. The artificial joint is called a prosthesis. Usually, bone cement is used to fix the prosthesis into the bone. In other cases, a prosthesis is used which allows the bone to grow onto the outer surface of the prosthesis.
Your surgeon will discuss with you the most suitable type of prosthesis based on your condition and health. The operation takes about 2 – 4 hours to complete.
About arthitis of the Hip
What is arthritis of the hip?
There are different types of Degenerative Joint Disease (DJD) that may cause hip pain. The following are some of the types of arthritis of the hip:
- Osteoarthritis (OA), also called as “wear and tear arthritis”, in which cartilage wears down over time
- Post-traumatic arthritis, which results from a severe fracture or dislocation of the hip
- Rheumatoid arthritis (RA), an inflammatory arthritis of the joints
- Avascular necrosis (AVN), a condition where the “ball” or femoral head has lost its healthy supply of blood flow causing the bone to die and the femoral head to become misshapen
- Hip dysplasia, a condition where bones around the hip did not form properly, which may cause misalignment of the hip joint
What causes arthritis of the hip?
The risk of developing symptomatic DJD is influenced by multiple factors such as age, gender, and inherited traits that can affect the shape and stability of your joints. Other factors can include:
- A previous hip injury
- Repetitive strain on the hip
- Improper joint alignment
- Being overweight
- Exercise or sports-generated stress placed on the hip joint
What are the symptoms of arthritis ?
- Pain while standing or walking short distances, climbing up or down stairs, or getting in and out of chairs
- Pain in the groin, thigh, or buttock area
- The affected hip feeling stiff or tight due to a loss in its range of motion
- Joint stiffness after getting out of bed
- Signs of limping and/or favoring the opposite leg as to not put any weight on the affected hip joint
Hip joint is exposed using a incision on the back of the hip and over the buttock. Joint is exposed after separating the muscle and cutting through the capsule. The worn and damaged surface of the bone and cartilage from upper end of femur (thigh bone) and pelvis are removed and shaped to accept the prosthetic implants. These surfaces are replaced with metal and plastic/ceramic implants.
Benefits of having the surgery
The pain gradually reduces making it possible to take up activities, which were difficult to perform prior to the surgery due to pain and stiffness in the hip joint.
Risks of not having the surgery
An increase in pain may affect the every day activities such as showering,walking, shopping, gardening, getting out of a chair, and climbing stairs. Improper joint transfer of weight may lead to abnormal posturing and this increases the risk of sustaining a fall.
Is the procedure safe?
This operation is one of the most cost effective and beneficial operations performed. Hip replacement surgery has evolved significantly over the last 40 years since it was first performed. There are improvements constantly being made but modern day hip replacements are extremely sophisticated and also function well for many years.
General risks of having an operation
There are risks with any operation:
- Secretions may collect in the lungs causing a chest infection
- Clotting may occur in the deep veins of the leg. Rarely, part of this clot may break off and go to the lungs. This can be life threatening
- Circulation problems to the heart or brain may occur which could result in a heart attack or stroke
- Death is possible during or after an operation due to severe complications
- Infection at the site of the surgery and/ or of the prosthesis
- With the advent of modern surgical implants, our highly equipped operation theatres and modern antibiotics, highly skilled intensivits and anaethetists, most of these complications can be avoided in majority of the patients and managed effectively
Types of total hip replacements
The replacement parts can be plastic (polyethylene), metal or ceramic and are used in different combinations
- Metal-on-plastic (a metal ball with a plastic socket) is the most widely used combination
- Ceramic-on-plastic (a ceramic ball with a plastic socket) or ceramic-on-ceramic (where both parts are ceramic) are often used in younger, more active patients
- Metal-on-metal (a metal ball with a metal socket) is very occasionally used in younger, more active patients
Metal-on-metal hip resurfacing
Resurfacing the original socket and the ball of the thigh bone is a different form of hip replacement. Instead of removing the head of the thigh bone and replacing it with an artificial ball, a hollow metal cap is fitted over the head of the thigh bone. The socket part of the joint is also resurfaced with a metal component.
People who have this type of operation have a lower risk of dislocation and may be able to return to a higher level of physical activity compared with those having a conventional hip replacement. There is a debate on the effect of metal ions released by the couple; the eventual effect of these ions isn’t clear yet, but there is research being going on in that subject.
Ceramic bearings are stronger, it is possible to use smaller acetabular shells. This means the surgeon has the opportunity to choose bigger femoral heads which will fit into smaller acetabular shells. This means higher stability, bigger ´Range of Motion` and less risk of impingement and wear of the material.
Revision Total Hip Arthroplasty
When 1 or both components of the prosthesis are loosened, a replacement will be mandatory. This is called a revision arthroplasty. There are several reasons for loosening the prosthesis:
- Osteolysis [bone resorption]
Revision arthroplasty implicate more extensive surgery with less chance for excellent clinical results
A candidate for total hip replacement may experience the following:
- Pain while putting weight on the affected hip
- Limping to lessen the weight-bearing pressure on the affected hip
- Pain that may radiate to the groin, lower back, or down the thigh to the knee
- Hip pain or stiffness during walking or other impact activities
- Failure to respond to non-surgical treatments or non steroidal anti-inflammatory medication
Most surgeries go well without any complications. Infection and blood clots are two serious complications that concern us the most. To avoid these complications, we use antibiotics and blood thinners. We also take special precautions in the operating room to reduce risk of infections. The chances of this happening in your lifetime are 1 percent or less. Dislocation of the hip after surgery is a risk.
Most hip-replacement patients are hospitalized for three to four days after surgery. If you need more time for rehabilitation, other options might be available to you.