This is an operation to “fuse” or stiffen the three main joints of the back part of the foot (hence “triple fusion”).
Why Would It Be Performed?
Triple fusion are done for two main reasons:
- Arthritis of the joints such as osteoarthritis due to a previous injury or rheumatoid arthritis.
- Severe deformity of the foot such as a flat foot, high-arched or “cavus” foot, a club foot or other deformity.
What Does It Involve?
Two incisions are made, one along the outer side of the foot over the side of the heel and one on the top of the foot. Each of the three joints is opened up; the joint surfaces removed and, if necessary, reshaped to correct a deformity. The bones are then put in the correct place and fixed together with screws or plates
The heel (“subtalar”) joint is usually fixed with a screw passed through a small incision in the back of the heel. The other joints are fixed through the main incisions. It is generally necessary to put some extra bone into a triple fusion to encourage it to heal and to fill any gaps in the fusion left by correcting the deformity.
Often, this extra bone can be obtained from the bone that is cut out to prepare the fusion. Sometimes, there is insufficient bone from this and bone has to be taken from the tibia bone just below the knee. Occasionally, if a large amount of bone is required, it must be taken from the pelvis just above the hip or received from a bone bank.
For those with a tight Achilles tendon (“heel cord”) or weak muscles or both, the Achilles tendon may be lengthened during surgery by making small incisions in the calf and stretching the tendon. Some people with deformities of the foot also have deformed toes. These may be corrected at the same time or more often at a later operation.
For more information on what to expect after surgery, please click the link for a detailed patient guide on this surgery.