Improved alignment of the knee through osteotomy takes stress off damaged areas and can delay the need for joint replacement by about 10 years for people with osteoarthritis of the knee.
Osteoarthritis often damages the cartilage more on one side of the knee than on the other. When that happens, the leg bones become misaligned, which can put even more stress on the already damaged joint.
Osteotomy is a "bone-cutting” surgical procedure that shifts the individual’s body weight from the damaged area of the knee toward the healthy side. This relieves pain and allows the knee to function more normally -- and that can buy time for a person who would like to delay total knee replacement surgery.
In an osteotomy for knee osteoarthritis, the surgeon removes a wedge of bone from the healthy shinbone (tibia). If the cartilage damage is on the inner side of the knee, bone is removed from the outer part of the shinbone; for damage to the outer side of the knee, bone is removed from the inner shinbone. The bone is taken from an area below the healthy cartilage. This allows the knee joint to open more freely and redistributes the weight across the joint.
Performed under general or regional anesthesia, osteotomy takes about 60–90 minutes to complete. The surgeon makes a 4- to 5-inch incision from just below the kneecap to below the top of the shinbone, and uses guide wires anchored into the top of the shinbone to outline the triangular area to be cut. The wedge is removed with an oscillating saw, and the top of the shinbone is lowered to reposition the joint. The realigned joint is held in place with staples or internal plates, or it may be immobilized with a cast.
Rehabilitation begins almost immediately after surgery with passive-motion exercises to flex and stretch the knee and restore adequate range of motion. You will be fitted with a knee brace (unless your leg is put in a cast) and will be on crutches for at least six weeks.
Physical therapy usually begins at about six to eight weeks, after the bone has had a chance to heal. The therapist will teach you stretching exercises at first and then strengthening and light aerobic activities.
Is Osteotomy Right for You? Osteotomy may be a good option for people under age 60 who want to delay a total knee replacement. Delaying knee replacement makes sense, because artificial knees wear out over time, often necessitating a second replacement surgery. Osteotomy can delay the need for joint replacement by about 10 years. The procedure is appropriate only when damage to the joint is uneven and no significant inflammation is involved.
