What is Knee Replacement Surgery?
Knee Replacement Surgery is a procedure with one of the best possible outcomes. It is performed when the knee joint gets worn out due to osteoarthritis or rheumatoid arthritis. In this surgery, the doctors change the surface of the upper thigh bone and the leg bone which comprises the knee joint, so that the bones no longer rub against each other.
The knee joint consists of the femur, also known as the thighbone, abutting the tibia, which is the bone of the lower leg and the patella (knee cap). In a total knee replacement, the diseased knee joint is replaced with an artificial substance. The ends of the femur and the tibia are removed and replaced with a plastic piece with a metal stem.
Types of Knee Problems
Knee pain can be categorized based primarily on its location; it can be lateral or medial and unilateral or bilateral.
Some of the most common types of knee pain are:
- Lateral Collateral Ligament (LCL) Injury: This occurs due to a sudden impact to the inside of the knee which can happen during twisting motion.
- Meniscus Tear: Meniscus are the two rubbery wedges of cartilage between the thighbone and shinbone, and can tear suddenly due to sudden force or the natural ageing process.
- Tendonitis: More commonly known as Jumper’s Knee, this occurs just below the knee cap in the front side of the knees. This results when the patellar tendon is overused and stressed.
- Iliotibial Band Syndrome: This frequently occurs in long-distance runners when the iliotibial band located on the outside of the knee rubs against the outside of the knee joint.
- Anterior Cruciate Ligament (ACL) Injuries: This ligament runs diagonally down the front of the knee and provides stability to the joints. This may require surgery.
Why is Total Knee Replacement required?
Total knee replacement is usually resorted to in case of chronic knee pain caused due to arthritis.
The types of arthritis which warrants this surgery are:
- Osteoarthritis: In this case, the bones start rubbing against each other due to the wearing down of the cartilage, a soft tissue which cushions the joints. This causes knee pain and stiffness.
- Rheumatoid Arthritis: The most common type of “inflammatory arthritis”, this condition is characterized by an inflamed synovial membrane which causes loss of cartilage, resulting in pain and stiffness.
- Post-traumatic Arthritis: This can occur due to any kind of knee injury which is accompanied by fractures of the bones surrounding the knee or any tears in the knee ligaments. This leads to a reduced knee function.
The Department of Orthopaedics at S.L Raheja (A Fortis Associate) is staffed with some of the best orthopaedic surgeons in Mumbai, adept at handling all the complex cases of knee replacement surgery.
What are the risks involved in knee replacement surgery?
Knee replacement surgery carries certain risks, including:
- Nerve damage
- Blood clots in the veins of the legs or the lungs
- Heart attack
- Pulmonary embolism leading to shock, shortness of breath and chest pain
- Urinary tract infection
- Potential lung, kidney and liver damage
Pre-Operative Evaluation For Total Knee Replacement
Before the surgery begins, the medical condition and history of the patient is ascertained and some tests
- The knee joints are carefully and thoroughly evaluated in order to ensure optimal recovery from the ensuing surgery.
- Blood tests of the liver and the kidneys and urine tests are carried out to detect any signs of anaemia or other conditions such as abnormal metabolism.
- Chest X-rays and ECGs are performed to check for signs of heart and lung disease.
- The weight of the patient is also given due consideration as the success of knee replacement surgery is greater if the patient is not obese or overweight.
Post-Surgery Operative Care
- After the surgery, which lasts for about two hours, the patient will be required to stay in the hospital for some days. During this period, he/she will be prescribed certain medications by the doctor to help control
- The day following the surgery, a physical therapist will guide the patient on how to exercise the new knee. Physical therapy must be continued even after the discharge of the patient.
- The patient will be given blood thinners and will be encouraged to move the foot and ankle in order to
improve the blood flow to the muscles in the leg and prevent swelling and clotting.
- In order to ease the passage of urine in the post-operative period, a catheter may be inserted into the
urethra to allow for the free passage of urine.
- In some cases, in order to speed the recovery, a Continuous Passive Motion (CPM) machine may be
attached to the operated leg. This continuously puts the knee through varying degrees of motion which
helps minimize the risk of scarring of the tissues around the knee.
- The patient is recommended to perform a variety of home exercises to strengthen the calf and thigh