In which cases is a knee prosthesis implanted?
A knee prosthesis is necessary when the knee joint is damaged or worn out. This causes the patient reduced mobility and pain, even when resting.
The most frequent reasons for a knee replacement are the following:
- Osteoarthritis
- Gout
- Trauma
- Hemophilia
- Rheumatoid arthritis
- Bone diseases
- Avascular necrosis
What types of knee prosthesis are there?
We will choose the type of knee prosthesis according to the needs of each patient. The type of joint wear, the stability of the soft tissues or if the patient has undergone previous surgeries will be assessed.
Among the most common prostheses we find:
- Total knee prosthesis: it is the most common. It is based on completely replacing both articular surfaces and consists of a tibial tray, femoral component, insert and patellar component.
- Unicompartmental knee prosthesis: it is mainly indicated to treat osteoarthritis of the knee, in which only the sides of the joint are affected. It is made up of the same components as the total prosthesis.
- Revision knee prosthesis: these are used when a previously implanted prosthesis has to be replaced. In these cases it is possible that there are stability problems and lack of bone, so biological products or prosthetic elements such as stems or supplements are used to fill the bone defects.
What does the knee prosthesis surgery consist of?
The intervention consists of removing the damaged bone and cartilage from the joint and replacing them with artificial pieces. These pieces can be placed at various locations on the knee:
- Lower end of the femur
- Upper end of the tibia
- Posterior side of the patella
The surgery lasts approximately two hours and general or regional anesthesia is used. First an incision is made in the joint of about 20 centimeters, then the patella is removed and the ends of the femur and tibia are cut. Once both parts of the prosthesis are fixed to the different bones with cement or screws, the muscles and tendons of the joint must be repaired and the incision closed.
How is the postoperative period after surgery?
The recovery time in the hospital will vary according to the patient and the type of surgery. Generally speaking, the patient will be discharged three to five days after surgery.
The patient will require the help of crutches initially, so you must follow some exercises to strengthen the knee. He/she will also have to follow different care in case that will be explained by the specialist.
Normally, about six weeks after surgery, the patient will no longer need the help of crutches. After eight to twelve weeks, he/she will be able to drive and lead a normal life again.
There is a very small percentage of patients who will still have some pain after two years.
For more information on knee replacements, contact a trauma specialist.