Your doctor may recommend surgery depending upon the extent of cartilage damage and your response to nonsurgical options.
Fusion. Fusion of the affected joints is the most common type of surgery performed for RA. Fusion takes the two bones that form a joint and fuses them together to make one bone.
During the surgery, the joints are exposed and the remaining cartilage is removed. The two bones are then held together with screws or a combination of screws and plates. This prevents the bones from moving.
Because the joint is no longer intact, this surgery does limit joint motion. Limited joint motion may not be felt by the patient, depending on the joints fused. The midfoot joints often do not have much motion to begin with, and fusing them does not create increased stiffness. The ankle joint normally does have a lot of motion, and fusing it will be noticeable to the patient. By limiting motion, fusion reduces the pain.
Fusion can be a successful technique. However, because patients with RA also show damaged cartilage and loose ligaments, the success rate of this type of surgery is lower in patients with RA than in patients without RA. The use of newer generation medication can slow the progression of the disease and impact the type of surgeries that can be performed successfully.
Other surgeries. The front of the foot is where there are more surgical options for some patients. Surgeons can now perform joint sparing operations to correct the bunion and hammertoes in some patients. Your surgeon will review the most appropriate options for your case.
Ankle
Ankle fusion and total ankle replacement are the two primary surgical options for treating RA of the ankle. Both treatment options can be successful in minimizing the pain and discomfort in the ankle. The appropriate surgery is based upon multiple factors and is individualized for every patient.
Patients with severe involvement of other joints around the heel or patients who have previously undergone a fusion on the other leg, may be more suited for ankle replacement. In addition, patients who have fusions within the same foot may be more suited for an ankle replacement.
Newer generation ankle replacement implants have shown promising early results. Ankle replacement implants have not yet been shown to be as long-lasting as those for the hip or knee, due to the fact that the newer generation of implants have not been available long enough to determine how long they will last.
Following ankle fusion, there is a loss of the up and down motion of the ankle. The up and down motion is transferred to the joints near the ankle. This creates a potential for pain in those joints, and possibly arthritis.
Patients are able to walk in shoes on flat, level ground without much difficulty after an ankle fusion, despite the loss of ankle motion. The joints in the foot next to the ankle joint allow for motion similar to the ankle joint, and help patients with fused ankle joints walk more normally.
Hindfoot (Heel Region of the Foot)
A fusion of the affected joints of the hindfoot is the most common surgery used to treat patients with flatfoot or arthritis of the hindfoot. A triple arthrodesis is a fusion that involves all three joints in the back of the foot. Occasionally, the joint on the outside of the foot is not fused if there is minimal to no involvement of that joint (this is at the surgeon’s discretion). This type of fusion eliminates the side-to-side motion of the foot, while preserving most of the up and down movement.
If RA is only in one joint, then a fusion of just that affected joint may be all that is needed.
Any fusion of the hindfoot will limit side-to-side motion of the foot. This will affect walking on uneven ground, grass, or gravel. There is no method to replace the joints of the hindfoot.
Midfoot (Middle of the Foot)
Fusion is the most reliable surgical method to treat RA of the midfoot joints. If the shape of the foot is not normal, surgery is designed to help restore the arch and minimize the prominences on the foot.
There are joint replacement implants available for joints on the outside of the midfoot. This may preserve some midfoot motion. However, the use of these implants is at the surgeon’s discretion. These implants are not available for the joints on the inside of the midfoot.
Although the foot cannot be returned to a normal shape, the goals are to reduce pain in the foot and improve the potential for the patient to wear more normal shoes.
Forefoot (Toes and Ball of the Foot)
The choice of treatment for patients with a bunion or lesser toe deformities (hammer or claw toes) depends on a number of factors.
If the disease is very mild, joint-sparing procedures that preserve motion can be considered. The decision is dependent on the medication that the patient is taking and the amount of damaged cartilage that is present. A fusion of the great toe may be recommended despite that fact the bunion is very mild. If there is damage to the cartilage of the great toe joint, correcting the bunion will not minimize the arthritic pain.
If the RA has progressed and the lesser toes (two through five) have dislocated, a complex operation to minimize the pain and restore the shape of the foot may be recommended. The operation involves fusion of the big toe and removing a portion of bone of each of the metatarsals. This surgery removes the prominent bone on the bottom of the foot that is a source of the pain and allows the toes to re-align into a better position.
Occasionally, the lesser toe metatarsals can be preserved by shortening them to allow the toes to resume their position within the joints. This is not always possible, however, and the joint may have to be removed.
To fix the bend in the toes themselves, the surgeon may suggest cutting a tendon or removing a small portion of bone of the toes to allow them to straighten. Pins that stick out of the foot are temporarily required and will be removed in the office after healing takes place.
There are some newer implants available that can be buried within the toes, which avoid the need for pins sticking out of the foot. These implants may not work if the bone is soft, or if significant destruction of the joints has occurred.
This operation puts a lot of stress on the blood vessels and skin of the foot. In severe cases, the toes may not survive the operation and may require amputation of a portion or the entire toe. This operation can provide the patient with a high level of function and the ability to enjoy a wider variety of shoewear.
Preparing for Surgery
Many of the medications that help with RA also affect the ability of the body to heal wounds and fight infection. Your surgeon will work with your rheumatologist or medical doctor to review which of your medications will need to be stopped prior to surgery. Once the wounds are healed, the medication is typically resumed.
This period of time can be very difficult for patients with other areas of the body that are affected by RA. Many fusions require at least 6 weeks of time where no pressure can be placed on the foot. Making appropriate preparations to ensure you have help at home is crucial for success after surgery.