Ankle fusion is a surgical procedure that locks up the ankle joint with screws, prohibiting the upward and downward motion of the ankle. Ankle fusion is one treatment option to relieve pain in patients who have a worn out ankle joint due to arthritis or a traumatic injury. It is also a treatment option for people with a severe deformity such as a flat foot, high-arched foot or a club foot in which the ankle joint is also deformed, unstable or damaged.
Sometimes ankle problems in the presence of major foot deformities can be treated by correcting the deformity by breaking and reshaping the foot bones or fusing the other foot joints, then clearing the out the ankle arthroscopically. In other cases it is best to stiffen the joint in the corrected position, particularly if the joint is already stiff or the foot is weak.
About 85 to 90 percent of ankle fusions are successful. Research shows that 10 percent of ankle fusions do not heal in exactly the position intended, either because the position achieved during surgery was not exactly correct or because the bones have shifted slightly in the plaster cast. Usually this does not cause any problem, although the foot may not look a little different. On occasion, the incorrect position is a problem and further surgery is required to correct it.
The surgery is performed under general anesthesia. A cut is made on each side of the ankle - about 3-4 cm long on the inner side of the ankle and about 10cm on the outer side. The bony bumps on each side of the ankle ("malleoli") are removed to allow the surgeon to get into the joint. The joint is opened up and the joint surfaces removed and, if necessary, reshaped to correct a deformity. Screws will be placed to allow the bones to heal together in proper alignment. A tibial bone graft may be taken from your knee area, to be used in conjunction with the screws. In general, patients undergoing ankle fusion surgery are admitted to the hospital for one or two days following surgery.
The hindfoot consists of four bones and three joints. The talus, calcaneus, cuboid, and navicular bones are separated by cartilage and create the talocalcaneal, talonavicular, and calcanealcuboid joints. A calcaneocuboid fusion fuses together the calcaneous and cuboid bones of the hindfoot.
The midfoot consists of the navicular, cuboid and three cuneiforms. A midfoot fusion fuses the bones of the midfoot that are causing the pain and disability.
The hindfoot consists of four bones and three joints. The talus, calcaneus, cuboid, and navicular bones are separated by cartilage and create the talocalcaneal, talonavicular, and calcanealcuboid joints. A subtalar fusion fuses together the subtalar joint.
The midfoot consists of the navicular, cuboid and three cuneiforms. A tibial/fibular fusion fuses the tibia and the fibula.
The midfoot consists of the navicular, cuboid and three cuneiforms. A talonavicular fusion fuses the talus and the navicular bones.
The hindfoot consists of four bones and three joints. The talus, calcaneus, cuboid, and navicular bones are separated by cartilage and create the talocalcaneal, talonavicular, and calcanealcuboid joints. A triple arthrodesis fuses together the three joints of the hindfoot.
Most people are in the hospital for 2 to 3 days. You can expect a great deal of swelling in your ankle, and will need to keep your foot elevated to help reduce the swelling. Once the swelling goes down and the incisions on your foot are healing, you will be put in a plaster cast from your knee to your toes. You will need to wear the cast until the ankle has fused - usually 3-4 months. For the first 6 weeks you should not put any weight on your foot as it may disturb the healing joint. While in the hospital, a physical therapist will teach you how to walk with crutches without putting weight on your foot.
Over the next few weeks, you will have X-rays taken to monitor the healing of your fused ankle joint. When the X-rays show that the joint is fused enough to take your weight, the cast will be removed and you will be given a brace to wear that will support you as you begin walking with weight on your foot again. The brace is usually worn for about a month.