As people age, bone, cartilage and tissue in their knees can wear away, causing pain and discomfort. Damage can also be caused by arthritis, degenerative bone disease and other chronic bone disorders that affect the joints and their surrounding tissues. Several types of knee replacement procedures can be considered, depending on the degree and type of disorder or injury.
Total Knee Replacement
A total knee replacement is performed when the knee joint is damaged due to injury or disease. A surgeon removes the entire joint, including the bone, joint and surrounding tissue, and puts a prosthesis in its place. Prostheses made of metal or plastic are attached to the ends of the femur and tibia. The posterior cruciate ligament and knee cap may be left in place if they are in good enough condition.
Partial (Unicompartmental) Knee Replacement
A partial knee replacement may be considered if only one compartment of the knee is diseased or damaged. Partial knee replacements are frequently considered if the patient is under the age of 60 and is not considered obese. Partial knee replacements may not last as long as total knee replacements.
Bilateral Knee Replacement
When a patient experiences severe pain and damage from arthritis or other bone disease in both knees, bilateral knee replacements may be performed. During bilateral knee replacements, both knee joints are replaced at the same time. Bilateral knee replacements are offered as an option to patients who want a quicker rehabilitation time. It drastically reduces mobility for four to six weeks and may not be an option for someone who needs to be able to get around quickly and easily at all times. In some cases, the pain is so severe that both knees are done at the same time to eliminate prolonged discomfort.
Implants
Two of the most common types of knee replacement implants are fixed bearing and medial pivot implants. Fixed-bearing implants are built to last longer and wear less. Medial-pivot implants allow the knee to pivot on the inner or medial condyle. This replicates the rotating, bending, twisting and flexion of the original knee. It also helps to stabilize the knee and protects it from further injury.
