Talocalcaneal Coalition Treatment 2026 | DPM

Coalition Type	Tissue	Subtalar Rigidity	Age of Symptoms	Surgical Approach
Fibrous	Dense fibrous tissue	Partial — still some motion	Younger (8–12)	Resection usually effective
Fibrocartilaginous	Fibrocartilage	Moderate — limited motion	10–14	Resection — good success if <50% facet
Osseous (bony)	Cortical bone	Complete — rigid hindfoot	12–16 (ossification completes)	Resection if early; fusion if arthritis present

Factor	Favors Resection	Favors Fusion
Age	<16 years (skeletally immature)	>16–18 years
Coalition size (% posterior facet)	<50%	>50%
Posterior facet arthritis	None	Moderate or severe
Prior surgery	No prior resection	Failed prior resection
Subtalar motion remaining	Some motion present	Completely rigid
Talar beaking severity	Mild	Severe (indicates chronic impingement)

Talocalcaneal Coalition Overview

Talocalcaneal (TC) coalition is an abnormal connection between the talus and calcaneus, most commonly at the middle facet of the subtalar joint. It accounts for approximately 37% of all tarsal coalitions. Like calcaneonavicular coalition, it presents in adolescence and can be bony, cartilaginous, or fibrous.

Symptoms

Symptoms mirror calcaneonavicular coalition: rigid flatfoot, peroneal spasm, subtalar pain (often felt deep below and behind the medial malleolus), reduced or absent subtalar motion, frequent ankle sprains, and pain with walking on uneven terrain. Bilateral involvement is common (~50%).

Diagnosis: The C-Sign

The “C-sign” on lateral foot X-ray — a C-shaped bony arch formed by the talar dome and the inferior border of the sustentaculum tali — suggests talocalcaneal coalition. However, CT scanning is essential for definitive diagnosis and surgical planning, as the middle facet is not well visualized on plain X-rays. MRI is best for cartilaginous and fibrous coalitions.

Conservative Treatment

Same as for calcaneonavicular coalition: activity modification, orthotics, cast immobilization for acute pain, physical therapy. Some patients manage long-term with orthotics alone.

Surgical Treatment

TC coalition resection is technically more demanding and has less predictable outcomes than CN coalition resection. It is appropriate only when the coalition is fibrous or cartilaginous, is less than 50% of the posterior facet, and there is no significant subtalar arthritis. For cases with arthritis or large coalitions, subtalar or triple arthrodesis (fusion) is the preferred option.

FAQs

Which coalition is easier to treat surgically? Calcaneonavicular coalition resection consistently produces better outcomes than talocalcaneal coalition resection due to more favorable anatomy and less risk of subtalar arthritis progression.

In-Office Treatment at Balance Foot & Ankle

If home treatment isn’t providing relief for your flat feet, our podiatry team at Balance Foot & Ankle can help with same-week evaluations and advanced in-office care.