Subtalar Implant for Adult Acquired Flatfoot

Overview

This procedure is designed to limit hyperpronation, an excessive range of motion of the subtalar joint typically caused by hereditary underdevelopment of the talus or the calcaneus. Hyperpronation can allow the foot to collapse inward and downward. During this procedure, a small device is implanted between the talus and calcaneus to correct this abnormal motion and stabilize the ankle. Several implant styles are available.

Preparation

In preparation for the procedure, the patient is positioned and anesthesia is administered. The surgeon creates a small incision on the outer side of the ankle to allow access to the sinus tarsi, the opening between the talus and calcaneus.

Inserting the Implant

The surgeon places a guide wire into the sinus tarsi, and then inserts a series of trial implants into this space to determine the appropriate size needed. When the correct size is determined, the surgeon inserts the permanent subtalar implant. The implant, which resembles a large screw, is designed to push apart the talus and calcaneus and hold them in proper alignment. The implant changes the shape of the foot, giving it more of an arch and correcting problems with posture and gait.

End of Procedure and Aftercare

When the procedure is complete, the incision is closed and bandaged. The ankle is placed in a splint or cast, and the patient is not allowed to bear weight on the ankle for the first two weeks. After that, the patient may be placed in a walking cast for two more weeks. Physical therapy will be needed.