Modern hip replacement surgery involves the implantation of a hip prostheses. For painful hips, worn out due either to avascular necrosis of the femur head or femoral neck fractures in combination with osteoarthritis, prostheses are implanted.
Completely cementless implants have been in use for over 20 years, and in recent years, minimally-invasive artificial joint replacement, e.g. short stem prostheses. Nowadays, prostheses are implanted with much smaller incisions and much less trauma to soft tissues.
What is a hip replacement?
During a hip replacement procedure, the damaged hip joint is replaced by an artificial hip joint prosthesis. The hip prosthesis is usually made of stainless steel or titanium. It can also be made of other metals, such as Niobium.
When might you need a hip replacement?
Hip replacements are carried out if the hip joint is in pain, with high grade osteoarthritis, and when conservative therapies are no longer useful. Other reasons to incorporate a hip prosthesis are femoral neck fractures or avascular necrosis of the femur head with joint destruction.
Typically, those needing a hip replacement will suffer aches when they start walking after resting periods. Late-stage cases suffer pain while resting too.
Types of hip prostheses
Depending on the type of anchoring, a distinction is made between cemented and cementless hip prostheses.
Depending on the design type, there are cup (e.g. McMinn) prostheses and short-stem prostheses. In addition, there are also normal length hip prosthesis stems and long-stem prostheses (for hip prosthesis replacement or special situations).
The surgical procedure
A hip prosthesis can be implanted through a front, side or rear surgical incision. The surgeon must also decide whether to go for short or conventional length incisions. The different approaches have specific advantages and disadvantages (more calcifications, closer to valves and nerves etc.). Naturally, all of these factors are assessed and weighed up carefully.
Once the procedure is defined and incisions have been made, the muscles and tendons are pulled aside and your surgeon then has direct access to the acetabulum (the socket of the hip bone). The acetabulum is then hollowed out using a special.
A socket is fitted into the hollow in the pelvis. A short, angled metal shaft (the stem) with a smooth ball on its upper end (to fit into the socket) is placed into the hollow of the thigh bone. The cup and the stem may be pressed into place (in the case of a cementless stem which is made from a material with a rough surface that allows the bone to grow on to it) or fixed with acrylic cement.
Finally, the area is closed back up, the skin is sutured and a sterile wound dressing placed.
In most cases after the surgical implantation of a hip prosthesis, it can bear weight immediately.
However, this is not always the case and it depends on the bone quality.
Subsequent use of forearm crutches can help to reduce pain during the first few days following the operation.
Dressings are changed and wounds drained approximately 2 days after surgery. The patient is discharged after approximately 5 to 7 days.
Depending on your job, you can resume work after about 6 to 8 weeks.