Adult acquired flatfoot or posterior tibial tendon dysfunction usually leads to a gradual loss of the arch. The posterior tibial muscle is a deep muscle in the back of the calf and has a long tendon that extends from above the ankle and attaches into several sites around the arch of the foot.

The muscle acts like a stirrup on the inside of the foot to help support the arch. The posterior tibial muscle stabilizes the arch and creates a rigid platform for walking and running. If the posterior tibial tendon becomes damaged or tears, the arch loses its stability and as a result, collapses, causing a flatfoot.

Possible complications from cyst removal surgery include infection, excessive swelling, and nerve damage.

Surgery is often performed to give the patient a more functional and stable foot. Several procedures may be required to correct a flatfoot deformity.

• Removal of inflammatory tissue and repair of the posterior tibial tendon.
• Isolated bone fusion procedures, bone grafts, and/or repositioning bones through cuts called osteotomies.
• Fusion procedures such as a triple or double arthrodesis, in which two or three major bones in the back of the foot are joined with screws or pins.