Knee replacement, also called knee arthroplasty or total knee replacement, is a surgical procedure to resurface a knee damaged by arthritis. Metal and plastic parts are used to cap the ends of the bones that form the knee joint, along with the kneecap. This surgery may be considered for someone who has severe arthritis or a severe knee injury.
Various types of arthritis may affect the knee joint. Osteoarthritis, a degenerative joint disease that affects mostly middle-aged and older adults, may cause the breakdown of joint cartilage and adjacent bone in the knees. Rheumatoid arthritis, which causes inflammation of the synovial membrane and results in excessive synovial fluid, can lead to pain and stiffness. Traumatic arthritis, arthritis due to injury, may cause damage to the cartilage of the knee.
The goal of knee replacement surgery is to resurface the parts of the knee joint that have been damaged and to relieve knee pain that cannot be controlled by other treatments.
The primary benefit that a knee replacement offer is relief of pain. Additionally, it allows correction of deformity and restoration of movement and joint stability. This leads to improved mobility and knee function and allows return to activities of daily living. The amount knee flexion (bending) one can get after knee replacement depends on the amount knee bending present before surgery, the quality of bone, the status and strength of the ligaments (collateral ligaments), the type of implant used, and the post-op rehabilitation (physiotherapy). Patients who are overweight may not get full flexion in their knees.
The majority of the patients with knee replacement can perform most of their activities of daily living. Most patients can walk without any walking aid, though some older patients may need to use a walking stick for support. Patients can climb stairs and sit and get up from a chair or couch on their own. Most patients can bend their knees to more than 120-130 degrees and are able to squat and sit cross-legged (Indian-style sitting). These activities need specific rehabilitation (exercise program) after surgery. It is however recommended that patients avoid such activities on a routine basis as it may put an undue strain on the knee which increases the wear and reduces the longevity of the artificial joint. Use of a western-style toilet is also recommended. Patients may be able to play sports like golf and tennis and drive a car once they have fully recovered from the surgery. Complete recovery may take about 2-3 months.
