This procedure is much less invasive than total knee replacement and may give relief to people suffering from arthritis of the knee or a knee injury. Partial knee replacement surgery replaces only the damaged area of your knee joint, may require only one or two days of hospitalization, and results in a shorter recovery time when compared with total knee replacement surgery.
The knee can be divided into three compartments: the medial compartment - the inside part of your knee, the lateral compartment - the outside part of your knee, and the patello-femoral compartment - the area where your kneecap rests. The unicompartmental implant is designed to replace either the media (inside) or lateral (outside) compartment.
The X-ray below left shows a right leg with a degenerated medial (inside) compartment. Notice how there is no space between the femur (thigh) bone and tibia (shin) bone. This bone on bone contact can be quite painful.
The partial knee replacement procedure begins with the exposure of the joint through a 3-4 inch incision. The surgeon then properly balances the knee joint. Next the surgeon shapes the end of the thigh bone (femur) and the top of the shin bone (tibia) to accommodate the unicompartmental knee replacement components. He places trial components on the bones to ensure proper alignment and removes them once this alignment is achieved. Finally, the surgeon implants the femoral and tibial components, closes the incision, and the procedure is complete.
You will be discharged when you can get out of bed on your own and walk with a walker or crutches, walk up and down three steps, bend your knee 90 degrees, and straighten your knee.
You will continue your home exercise program and go to outpatient physical therapy, where you will work on an advanced strengthening program and such programs as stationary cycling, walking, and aquatic therapy.
Your long-term rehabilitation goals are a range of motion from 100-120 degrees of knee flexion, mild or no pain with walking or other functional activities, and independence in all activities of daily living.