Total knee Replacement

A total knee replacement is a surgical procedure whereby the diseased knee joint is replaced with artificial material. The knee is a hinge joint that provides motion at the point where the thigh meets the lower leg. The thigh bone (or femur) abuts the large bone of the lower leg (tibia) at the knee joint.

Total Knee Replacement Surgery

During a Total Knee Replacement Surgery, the end of the femur bone is removed and replaced with a metal shell. The end of the lower leg bone (tibia) is also removed and replaced with a channeled plastic piece with a metal stem. Depending on the condition of the kneecap portion of the knee joint, a plastic “button” may also be added under the kneecap surface. The artificial components of a total knee replacement are referred to as the prosthesis.

The posterior cruciate ligament is a tissue that normally stabilizes each side of the knee joint so that the lower leg cannot slide backward in relation to the thighbone. In Total knee replacement surgery, this ligament is either retained, sacrificed, or substituted by a polyethylene post. Each of these various designs of Total knee replacement has its own particular benefits and risks.

“Total knee replacement surgery has to be done when all the joint compartments are affected by the loss of cartilage/arthritis.”

The Knee Joint is Divided into 3 Compartments:

1. Medial tibio-femoral (inner half of knee)
2. Lateral tibio-femoral (outer half of knee)
3. Patello-femoral (front of the knee)

Indications of Total Knee Replacement

1. A significant amount of pain is associated with osteoarthritis in the medial compartment (especially during lifting weights).
2. Most of the pain is medial, but little or no anterior pain.
3. Varus deformity that is not greater than 15 deg.
4. Fixed flexion deformity no greater than 15 degrees.
5. Flexion higher than 120deg.
6. Correctable varus deformity.
7. Affective lateral space.
8. Anterior and posterior Cruciate ligaments.
9. If there is no anterior knee discomfort the the patellofemoral joint does not matter in the absence of significant degeneration.
10. The X-ray shows a narrowing on one joint.
    
    

What are the Symptoms and Causes of Total Knee Pain?

1. Pain and swelling of the knee.
2. Difficulty in walking, climbing stairs.
3. Limp while walking.
4. Cramping pain in the calf muscles.

“Symptoms get relieved on taking rest.”

What are the next steps after knee replacement?

After knee replacement you need immediate attention. Consult total knee replacement surgeons for a physical exam.

What Investigations are Needed for Total Knee Replacement?

• X-ray – to determine the stage of arthritis, exact involvement of knee compartments, bone overgrowth, bone defect.

• MRI Scan – to further quantify the problem- cartilage defect, arthritis, or damage to other joint structures such as ACL/PCL/meniscus.