Tarsal Coalitions
Overview
A tarsal coalition is an abnormal connection between bones in the back or middle of the foot. It may be fibrous, cartilaginous or bony. Many coalitions never cause symptoms. Others become painful as the connection stiffens, after injury or with increased activity. Treatment depends on the coalition, the condition of nearby joints, flexibility, alignment and where the pain actually comes from.
Common types and symptoms
The most common coalitions are connections between the heel and navicular bones (calcaneonavicular) or between the talus and heel bone (talocalcaneal). More than one coalition may occur, and the other foot can also be affected. Symptoms include activity-related pain in the back or middle of the foot, stiffness on uneven ground, repeated sprains, muscle spasm and a flat or less mobile foot.
Pain does not always arise directly from the coalition. Adjacent joints, impingement and the resulting foot deformity may become symptomatic, so the whole foot must be assessed.
Assessment and imaging
Examination assesses arch and heel alignment, side-to-side movement at the heel, areas of tenderness, calf tightness, muscle spasm on the outer side and whether the deformity remains flexible. Both feet are compared.
Weight-bearing X-rays may show a coalition or indirect signs. CT defines a bony connection and joint shape. MRI is useful for a fibrous or cartilaginous coalition and for associated bone stress or tendon disease. Imaging of the opposite foot is considered when symptoms or planning make it relevant.
Non-surgical treatment
- Activity modification during painful flares.
- Supportive footwear and an insole (orthosis) to improve comfort and load distribution.
- Physiotherapy for calf flexibility, strength, balance and movement in joints that remain mobile.
- A short period in a cast or Moonboot for a significant flare.
- Pain-relieving or anti-inflammatory medicine when medically appropriate.
- A guided injection into an adjacent painful joint in selected cases; this may provide temporary relief or help localise symptoms but is not a cure.
When may surgery be considered?
Surgery may be discussed when persistent pain and functional restriction continue despite appropriate non-surgical care. Age, coalition size and type, flexibility, joint cartilage, foot alignment and the location of pain determine whether joint-preserving surgery is reasonable.
Resection removes the coalition and places tissue between the bones to reduce reformation. It is most suitable when nearby joints remain healthy and the foot is reasonably flexible. Resection alone may be inadequate when substantial flatfoot or another deformity remains, and corrective bone procedures may be added.
When is fusion considered?
Fusion is considered when the affected or adjacent joint is arthritic, the foot is rigid, the coalition is not suitable for resection or previous treatment has failed. The operation may involve the subtalar, talonavicular or other selected joints and may be combined with realignment.
Fusion trades painful motion for stability and can place additional load on neighbouring joints. It is therefore used selectively, particularly in younger people.
Recovery
Recovery ranges from relatively early movement after removal of an isolated coalition to prolonged non-weight-bearing after a corrective bone cut or fusion. A cast or Moonboot is used, and physiotherapy restores movement, strength and confidence as healing permits.
Return to school, work and sport depends on the operation and whether bone healing is required. Swelling and adaptation can continue for months.
Risks and limitations
- Persistent pain if another coalition, deformity or joint is the main pain source.
- Recurrence or incomplete restoration of movement after resection.
- Nerve injury, numbness, wound problems or infection.
- Delayed healing or failure of bone healing after a corrective bone cut or fusion.
- Residual or recurrent deformity and adjacent-joint overload.
- Need for further surgery.
Frequently asked questions
Is a tarsal coalition present from birth?
Most are developmental, but symptoms often begin only when the connection stiffens or activity increases.
Does every coalition need treatment?
No. An incidental, painless coalition requires no operation.
Why can a tarsal coalition lead to ankle sprains?
Reduced hindfoot movement and altered alignment can shift stress to the ankle and create recurrent giving-way symptoms.
Can the coalition simply be removed?
Sometimes. Resection works best when joints are healthy and deformity is flexible. Alignment may need correction at the same time.
Can adults have coalition surgery?
Yes, but adults more often have established arthritis or rigid deformity, which can make fusion more appropriate than resection.
General information
This page provides general information only. It cannot diagnose your condition or replace advice from a clinician who has assessed you. Your treatment and recovery plan may differ from the examples described here. Follow the instructions from your treating team. In an emergency, call 000 or attend the nearest emergency department.