Hindfoot fusion (or rearfoot fusion) is considered to relieve severe pain from arthritis or to correct a foot deformity, such as clubfoot or grow defects due to conditions such as Spina Bifida. The number of joints fused depends upon the severity of the arthritis or defect of the foot.
In some cases, it is only necessary to fuse the subtalar joint. However, it may be necessary to fuse two or three of the hindfoot joints, known as double and triple fusions.
The hindfoot enables the foot to make most of its sideways movements. It consists of three joints which lie around and below the ankle – the subtalar, the calcaneocuboid and talonavicular joints.
How does Hindfoot Fusion work?
If the fusion involves the subtalar joint only, an incision is made on the outside of the foot just below the ankle. Double and triple fusion requires an additional incision on the inside of the foot.
The surgeon will remove damaged cartilage and position the joints correctly. They are then fixed in this position using metal screws. Positioned correctly, the screws will not be felt by the patient and will remain in place for many years and there is normally no need to remove them. The operation allows the bones to knit together into a cohesive, painless structure.
How long will it take to recover?
If you have a triple fusion, you are likely to spend about three days in hospital; less for a single or double fusion. You will wear a plastercast for the first six weeks and during this time you must not weight bear as this is the period when your bones are in the process of knitting together.
Your plaster will typically come off at about nine weeks and is replaced by an Aircast, a flexible boot which protects your foot but allows for flexibility.
From three to six months post surgery, you will gradually start to weight bear and build up your mobility and strength with physiotherapy. Full recovery will take 10 months to one year.
There will be some loss of mobility, depending upon the joints which have been fused together. However, patients are able to resume their old activities, including walking, climbing, running and playing tennis. Orthotics are normally sufficient to address any mobility problems.