Even though half a million knee replacements are done each year in the United States, there are other treatment options for some patients. If one side of the joint has worn down from problems with alignment, an osteotomy is one possible alternative choice.
What’s an osteotomy? Basically, an osteotomy is a surgical procedure whereby a bone is cut to shorten, lengthen, or change its alignment. Around the knee, it’s the tibia (the lower leg bone) that is involved. The various kinds of osteotomies are often named for their location. The two most basic types are opening wedge and closing wedge osteotomies.
When is an osteotomy a good idea? The purpose of the osteotomy is to shift the patient’s body weight off the damaged area to the other side of the knee. This makes better use of the cartilage that is still healthy.
The surgeon removes a wedge of the tibia from the healthy side of the knee. It might be taken from the inside (medial) of the tibia (meaning the side of the knee closest to the other knee). That’s an opening wedge osteotomy or medial opening wedge HTO. HTO refers to high tibial osteotomy meaning the wedge is removed right at the upper end of the tibia just under the knee joint.
A closing wedge osteotomy (also known as a lateral closing wedge HTO) takes the piece from the lateral tibia and allows the remaining edges of bone to collapse toward each other to close the gap. Once the wedge is removed, the bones are brought together and held in place with a metal plate or pins.
Whether it’s an opening or closing wedge procedure, an osteotomy allows the tibia and femur to bend away from the damaged cartilage. A tibial osteotomy can enable younger, active osteoarthritis patients to continue using the healthy portion of their knee. As you found out, the procedure can delay the need for a total knee replacement for up to ten years.