Definition:
Total knee replacement is a medical procedure applied for changing the diseased
knee joint with an artificial joint. Our knee is made up of Femur (lower end of
thighbone) rotating on upper end of Tibia (shin bone) and Patella (knee cap) sliding
in a groove on the end of Femur. Knee is a pivot joint that provides movement at
the point where thighs meet lower leg. Artificial joint used in the surgery is made
of metal and plastic components. The need for this surgery arises because of debilitating
pain that includes meniscus tears, osteoarthritis, cartilage defects and ligament
tears. There are 3 types of knee replacement procedure:
- Non-constrained: In this type of surgery, the artificial components
placed in the knee are not connected to each other and have no steadiness built
in the system. These components rely on the patient’s own ligaments and muscles
for stability.
- Semi-constrained: This type of implant provides increasing permanence
to the knee, as the artificial components have some stability built into it. It
is used by the surgeon, when he or she needs to remove all the inner knee ligaments.
- Constrained or hinged: These type of implants have two components
of the knee joint are linked together with hinged device. This kind of knee replacement
is needed, when knee is found to be highly unstable and the patient’s ligaments
are not at all supportive for other knee replacements.
The medical procedure is started by giving anaesthesia, general or epidural. In
the first case, you will be asleep during your surgery and the latter case will
anesthetize your legs. After that, the surgeon will remove your damaged cartilage
and bone. Then, he will place the new metal and plastic joint surfaces to restore
the alignment/ function of the knee. Usually, the surgery procedure takes 2 hours.
The artificial joint placed consists of a femoral component (created from highly
polished tough metal), tibial component (made of strong plastic held in a metal
tray) and patellar component (made of plastic).
Purpose:
Total knee replacement (TKR) is one of the most common treatments for knee joint
pain. The purpose of carrying out this treatment is to improve the performance of
knee joint. As knee joint functioning is connected with its stability, this treatment
also enhances the constancy of knee and artificial joint implanted. Knee is the
largest joint in our body and TKR is an advisory treatment for patient’s that cannot
get their knee pain treated with any other procedure.
Precautions:
After the surgery is completed, the patient is not allowed to do jogging and high-impact
sports for the entire life. Excessive weight on artificial joint tends to cause
some wear in the plastic cushion causing excessive pain. So, it is highly recommended
that you should avoid putting any kind of weight on your knees.
Pre and Post Care:
Before going for operation, the surgeon might ask you to lose weight and increase
suppleness in the knee joint. You will also be required to quit smoking as it weakens
the cardiovascular system, which may cause breathing problem under anaesthesia.
Another pre-operative care includes stopping of other medicinal treatments two weeks
prior to surgery.
After the surgery is done, the surgeon will give intravenous antibiotics to prevent
any kind of infection. You will also be given medications for making your blood
thinner, so that you may not get blood clots in the legs. Even, light ankle and
feet exercises are also suggested to avoid stiffness. On leaving the hospital, your
surgeon will ask you to undergo physical therapy for better and faster results.
This will also include doing low-impact exercises, such as cycling, swimming and
walking. In order to avoid excessive pain, you can take aspirin or ibuprofen (pain
killers) 45 minutes before doing exercise.
Risk Factors:
Though total knee replacement treats chronic pain of knee joints; it also has some
risk factors. But, proper care will lessen the chances of having following problems:
- Blood clots in legs that can travel to lungs causing chest pain and shortness of
breath
- Urinary tract infection
- Bleeding into the knee joint
- Blood vessel injury
- Infection in the knee that may require another surgery
- Dislocation/ Loosening of prosthesis
Hospital Stay:
The pre-operative, surgery and post-operative stages of total knee replacement may
require you to stay for over one week in the hospital. Those who undergo bilateral
knee replacement (both knees replaced) may require staying at some rehabilitation
centre for a longer period of time.
|