The knee is made up of the lower end of the thigh bone (femur), which rotates on the upper end of the shin bone (tibia), and the knee cap (patella), which slides in a groove on the lower end of the femur. Large ligaments attach to the femur and tibia to provide stability. The long thigh muscles (quadriceps) give strength to the knee.
The joint surfaces where these three bones touch each other are covered with articular cartilage, a smooth substance that cushions the bones and enables them to move easily.
When one compartment of knee joint is arthritic then replacing this part with metal and plastic joint known as unicompartmental knee replacement. As compare to total knee replacement whole joint cartilage is not replaced. Benefit of this operation is that patient can bend the knee fully and can squat. Hospitalization for this surgery is just three days.
The partial knee replacement surgical procedure has generated significant interest because it entails a smaller incision and faster recovery than traditional total joint replacement surgery. Partial knee replacement, also called unicompartmental knee replacement' and 'minimally invasive knee surgery,' removes only the most damaged areas of cartilage, and replaces these surfaces.
After conventional knee replacement generally one gets 90 to 100 degrees of knee flexion or bending as conventional knee replacement prosthesis design accommodate flexibility up to 100 degrees. For most patients this is not enough as many daily activities require the ability to flex the knee beyond 125 degrees.
Recent innovation of knee design is the real break through where complete flexion could be achieved. Desire for high flexion may be dictated by patient's favorite activities or cultural background
Minimally invasive total knee replacement is a technique developed to minimize the negative effect on the quadriceps muscle (the muscle that runs across the front of your thigh). When you straighten out your knee while you are sitting, you feel this powerful muscle working in front of thigh and knee is quadriceps. The center of the quadriceps muscle is the quadriceps tendon, which provides much of the power to the knee joint.
In traditional knee replacement surgery, this muscle and tendon group is usually split lengthwise to gain access to the knee. It is sewn and repaired at the end of the surgery. In minimally invasive knee replacement surgery, the knee joint is accessed without cutting through the quadriceps tendon called "quad-sparing". Patients have found they experience less pain and a quicker recovery with this type of surgery.