Introduction

Uni-compartmental knee replacement surgery utilizes specially designed implants made to resurface one side of the knee joint, and eliminate activity limiting arthritic pain restoring more normal knee function. They are attached to the ends of the femur (thigh bone) and tibia (shin bone), and move on one another during motion.

This surgery is often referred to as "less invasive" or "minimally invasive" because the procedure requires a smaller incision compared to a total knee replacement. The procedure also removes less bone and retains more of the supporting soft tissue than a total knee replacement. The existing ligaments and muscles are maintained for stability and movement of the knee. By resurfacing the arthritic bones, your arthritis pain may be reduced, allowing you to regain a more normal level of activity.  Uni-compartmental knee replacement, also called partial knee replacement, may restore your knee joint's natural range of motion, reduce pain and stiffness.

Surgical Procedure

After you have been prepared for surgery and given an anesthetic, your knee will be cleaned with a solution to sterilize the skin around the entire knee and sterile drapes will be applied to isolate your leg from the rest of your body.  An incision will be made over the side of the knee where the arthritis is located. Once the knee joint is visible, the surgeon will bend and straighten your knee and check the surfaces of the bones, the ligaments, the cartilage and other structures to assess the damage to the joint.   Following this assessment, your surgeon will proceed in resurfacing the arthritis or diseased knee compartment.

The surgeon will remove the worn out and damaged cartilage surfaces of the shin bone (tibia) and thigh bone (femur) at the knee joint, including small segments of bone necessary for anchoring the implants. The surgeon will use surgical instruments to remove the proper amount of bone from the tibia and femur and to assure the correct alignment of the artificial implants.

The tibial and femoral implants are inserted covering the areas where the arthritic bone has been removed. These components will be secured to the ends of the bones with a caulk-like material known as bone cement.

After the knee has been resurfaced, your surgeon will check the alignment of the implants and verify the knee joint's range of motion by bending and straightening your leg. The layers of tissues covering you knee are then carefully repaired. The incision is closed with removable or absorbable stitches and a large bandage is applied to your knee. You will be taken off the anesthesia medication and moved to the recovery room. Partial knee replacement surgery usually takes one to two hours. You should plan to remain in the hospital for one or two days after surgery depending on your surgeon's advice.