The hip is a ball and socket joint. A total hip is a surgical procedure where one's arthritic "ball" is removed and replaced with a cobalt chrome steel ball set on a stem. The stem is inserted into the femoral (thigh bone) canal and most commonly fixed with cement. Your socket is reamed (sanded) down to healthy bone and a plastic(high density polyethylene) cup is then placed there and held in place with cement.
Cemented prostheses were developed 30 years ago. Uncemented prostheses were developed about 15 years ago to try to avoid the possibility of loosening parts and the breaking off of cement particles, which sometimes happen in the cemented replacement. Because each person's condition is unique, the doctor and patient must weigh the advantages and disadvantages to decide which type of prosthesis is better.
The primary disadvantage of an uncemented prosthesis is the extended recovery period. Because it takes a long time for the natural bone to grow and attach to the prosthesis, people with uncemented replacements must limit activities for up to 3 months to protect the hip joint. The process of natural bone growth also can cause thigh pain for several months after the surgery.
Research has proven the effectiveness of cemented prostheses to reduce pain and increase joint mobility. These results usually are noticeable immediately after surgery. Cemented replacements are more frequently used than cementless ones for older, less active people and people with weak bones, such as those who have osteoporosis and in patients with rheumatoid arthritis.
Total hip replacements are performed for individuals who have severe pain, significant loss of motion and the inability to perform reasonable routine and recreational activities. This is an elective surgery, it is not a matter of life or death. The decision to proceed with a total hip replacement is ultimately yours, it is you who must accept the risks and potential complications. Please feel free to ask your physician questions to assist you in your decision making. In the past, hip replacement surgery was an option primarily for people over 60 years of age ,however, doctors have found that hip replacement surgery can be very successful in younger people as well. New techniques and technology have improved the artificial parts, allowing them to withstand more stress and strain.
Results are generally very good, most people are relieved of most of their hip and groin pain. Approximately 90% of total joints will last 10 years and 80% will last a person 20 years.
Approximately 45,000 hip replacement operations are performed each year in the United Kingdom and less than 10 percent require further surgery. The most common problem that may happen soon after hip replacement surgery is hip dislocation. Because the artificial ball and socket are smaller than the normal ones, the ball can become dislodged from the socket if the hip is placed in certain positions. The most dangerous position usually is pulling the knees up to the chest. Generally the incidence of hip dislocation is no more than 1% .
can happen in less than 0.5% cases and in sever cases may require further surgery to eradicate the infection. In most severe infections the artificial hip may need to be taken out and a further replacement can only be done after the infection has settled completely.
in the calf veins can happen in a small percentage of patients and in rare cases, these clots may travel up to the lungs and cause a fatal heart attack. Special stockings and blood thinning medicines are provided to reduce this complication. The best way to avoid clot formation is to keep on moving your ankles up and down and to keep on tensing your thigh muscles, as this aids blood flow. In addition, early mobilisation by putting full weight on the legs is very important.
Some patients may find that their legs are not of exactly similar lengths after operation. This could be due to the other hip also being worn out and may equalise after replacement of the worn other hip. Generally the difference in the leg lengths
is no more than 1/2 to 3/4 cms and does not cause any problems.
In very rare cases, particularly if there has been previous surgery around the hip, there may be damage to the sciatic nerve which may lead to weakness of some leg and foot muscles. This may improve with time over 12-18 months. The most common late complication of hip replacement surgery is an inflammatory reaction to tiny particles that gradually wear off of the artificial joint surfaces and are absorbed by the surrounding tissues. The inflammation may trigger the action of special cells that eat away some of the bone, causing the implant to loosen. This problem generally does not arise before 8-10 years.
In general, for the vast majority of the patients, a TOTAL HIP REPLACEMENT
is a very successful operation and probably 98-99% patients will go through the operation without any major problems.