Tarsal Coalition Treatment 2026 | DPM

Coalition Type	Joints Involved	Frequency	Age at Presentation	Key Finding
Calcaneonavicular (CN)	Calcaneus to navicular	Most common (53%)	8–12 years	Anteater sign on lateral X-ray; CT confirms cartilaginous or bony bar
Talocalcaneal (TC)	Middle facet of subtalar joint	Second most common (37%)	12–16 years	Ball-and-socket ankle on X-ray; C-sign; MRI best for fibrocartilaginous coalitions
Talonavicular (TN)	Talonavicular joint	Rare (<10%)	Variable	Severe rigid flatfoot; often bilateral; associated with other syndromes
Calcaneocuboid (CC)	Calcaneocuboid joint	Rare (<5%)	Variable	Often incidental; rarely symptomatic
Fibrous (Syndesmosis)	Any of above	Common subtype	Any age	Motion preserved but painful; MRI shows marrow edema at bar
Cartilaginous (Synchondrosis)	Any of above	Common subtype	Ossifies in teens	Not visible on plain X-ray; CT/MRI required

Treatment	Indication	Procedure	Success Rate	Recovery
Conservative (casting + orthotics)	First episode pain; mild symptoms; age <10 with open physis	4–6 weeks cast immobilization, then custom orthotics	50–60% long-term pain relief	6–8 weeks casting; ongoing orthotics
Resection + Fat Graft (CN Coalition)	Symptomatic CN coalition, <50% joint involvement, no OA	Excise bony/fibrocartilaginous bar; interpose fat graft to prevent recurrence	80–90% in adolescents with no arthritis	4–6 weeks NWB; 3–4 months full activity
Resection (TC Coalition)	TC coalition <50% middle facet involvement	Excise via sinus tarsi approach; fat or EDB graft	70–85% if <50% facet involved	4–6 weeks NWB; 3–4 months
Subtalar Arthrodesis	TC coalition >50% involvement; OA present; failed resection	Fusion of subtalar joint; eliminates pain permanently	90–95% pain relief	8–12 weeks NWB; 6 months full activity
Triple Arthrodesis	Pan-tarsal OA; failed subtalar fusion; severe deformity	Fuse subtalar + talonavicular + calcaneocuboid joints	85–90% pain relief	10–14 weeks NWB; 6–12 months

Medically reviewed by Tom Biernacki, DPM — Board-Certified Foot & Ankle Surgeon · Updated May 2026 · Balance Foot & Ankle PLLC, Howell & Bloomfield Hills MI

Quick Answer

A tarsal coalition is an abnormal bony, cartilaginous, or fibrous bridge between two of the back-foot bones — usually the calcaneus and navicular (calcaneonavicular coalition) or the talus and calcaneus (talocalcaneal coalition). It causes a stiff, painful, often flat foot in adolescents (ages 8–16) when the bridge ossifies. Treatment starts with immobilization, orthotics, and physical therapy, with surgery (resection ± arthroereisis or subtalar fusion) reserved for refractory cases. Outcomes after resection are excellent in 75–90% of properly selected adolescents.

If your teenager has a stiff, flat foot that hurts after sports — especially with side-to-side motion or running on uneven ground — and the pain has been brushed off as “growing pains” or chronic ankle sprains, the answer may be a tarsal coalition. This is one of the most commonly missed diagnoses in pediatric foot pain, and the window for the easiest, most successful treatment is exactly the years when teens are most likely to be told their pain is psychological. In our clinic, we see tarsal coalitions in athletes ages 8 to 18 who have been ruled “fine” on x-rays and finally get the right answer when we order a CT or MRI. Catching it early changes the entire trajectory.

What Is a Tarsal Coalition?

A tarsal coalition is an abnormal connection between two of the seven tarsal bones in the back of the foot. The connection can be made of bone (osseous), cartilage (cartilaginous), or fibrous tissue, and the underlying problem is the same: motion between the bones is restricted, the subtalar joint cannot tilt and rotate normally, and the entire hindfoot becomes stiff. Around 1–2% of the general population has a tarsal coalition, and about half of those are bilateral. The condition is congenital — you’re born with the bridge — but it usually doesn’t cause pain until the bridge ossifies in adolescence (typically ages 8–16), at which point the loss of motion becomes mechanical and symptomatic.

The clinical picture is classic: a previously athletic kid develops a stiff, painful flat foot that does not improve with standard arch supports. They sprain the ankle repeatedly because the hindfoot cannot adapt to uneven ground. The flatfoot is rigid — it doesn’t reform an arch when the patient stands on tiptoe (the “Jack toe-raise test”). And the pain is often felt deeper than they can point to, which is why x-rays are unrevealing and the diagnosis is usually delayed by 6–18 months from symptom onset to the right scan.

Types of Coalitions: CN vs TC

Two coalitions account for about 90% of cases: calcaneonavicular (CN) coalition, the bridge between the front of the heel bone and the navicular, and talocalcaneal (TC) coalition, the bridge between the talus and the middle facet of the heel bone. Each has a distinct presentation, symptom-onset age, and surgical approach. Less common forms include calcaneocuboid, talonavicular, and cubonavicular coalitions, which together make up the remaining 10%.

• Calcaneonavicular (CN) coalition — about 50% of all coalitions. Symptomatic ages 8–12 (when it ossifies earlier). Best seen on a 45° oblique x-ray as the “anteater nose sign.” Easier to resect surgically.
• Talocalcaneal (TC) coalition — about 40% of all coalitions. Symptomatic ages 12–16 (later ossification). Located at the middle subtalar facet. Requires CT or MRI for diagnosis and a more complex surgical approach.
• Calcaneocuboid, talonavicular, cubonavicular — rare; account for <10% combined.
• Multiple/bilateral coalitions — about 50% of patients with a coalition have one in the opposite foot, often subtype-matched.

Symptoms: When the Bridge Ossifies

The hallmark symptoms of a tarsal coalition are chronic deep aching pain in the back of the foot or sinus tarsi area, recurrent ankle sprains in an adolescent athlete, and a stiff flatfoot that does not reform an arch on tiptoe. Pain is typically worst with running, jumping, walking on uneven ground, or sports that require lateral cutting (soccer, basketball, lacrosse). Symptoms intensify during growth spurts when the cartilaginous bridge progressively ossifies into rigid bone.

• Chronic deep ache in the sinus tarsi (just in front of the lateral ankle) or medial mid-foot.
• Recurrent ankle sprains — the rigid hindfoot cannot accommodate uneven ground and gives way.
• Rigid flatfoot — the arch does not restore on tiptoe (positive Jack test).
• Restricted subtalar motion — you can’t tilt your heel inward or outward more than a few degrees.
• Peroneal spasm — the peroneal tendons spasm into eversion, sometimes called “peroneal spastic flatfoot.”
• Pain after sports rather than during — symptoms classically build over the next 12–24 hours.
• Activity tolerance dropping — the kid can no longer keep up with peers in sports they used to dominate.

Causes & Genetics

Tarsal coalitions are congenital — the abnormal bridge forms during fetal development, not from injury or repetitive stress. Roughly 1–2% of the general population has at least one coalition, and about half are bilateral. Inheritance is autosomal dominant with variable expressivity, meaning a parent with a coalition has roughly a 50% chance of passing it to each child, but the child may be asymptomatic. Many coalitions are silent for life and only discovered incidentally on imaging.

Pain begins not because the coalition appeared but because it ossified. In early childhood the bridge is cartilaginous and slightly flexible, and the subtalar joint can still move enough for normal play. As the child grows, the cartilaginous bridge progressively turns to rigid bone — CN coalitions ossify around ages 8–12, TC coalitions around 12–16. Once the bridge is bone, the joint locks, and clinical symptoms begin. This explains the classic “previously normal teenager develops painful stiff flatfoot” presentation.

⚠️ Key Takeaway

Any adolescent athlete with recurrent ankle sprains and a stiff flatfoot should be screened for a coalition. Standard x-rays miss roughly 30% of tarsal coalitions, especially talocalcaneal types. If clinical suspicion is high, an MRI or CT is the next step — do not accept “x-rays are normal” as a final answer.

How We Diagnose Tarsal Coalition

Diagnosing a tarsal coalition begins with a careful exam and ends with the right scan. The single most useful exam test is the toe-raise test: a normal flatfoot reforms an arch and the heel inverts when the patient stands on tiptoe; a coalition flatfoot stays flat and the heel does not invert. Combined with restricted subtalar motion and tenderness over the sinus tarsi or under the medial malleolus, the toe-raise test virtually nails the diagnosis before any imaging.

1. Targeted history — recurrent sprains, post-activity ache, age 8–16, family history of foot problems.
2. Standing exam — rigid flatfoot, valgus heel, abducted forefoot (“too many toes” sign).
3. Jack toe-raise test — the arch does not reform on tiptoe; heel does not invert.
4. Subtalar range of motion — severely restricted (often <5° total inversion-eversion).
5. Weight-bearing x-rays — AP, lateral, and 45° oblique views; look for the anteater nose sign (CN), C-sign (TC), or talar beaking.
6. CT scan — gold standard for visualizing bony coalitions and surgical planning.
7. MRI — identifies cartilaginous and fibrous coalitions that CT misses; also rules out other causes.

Imaging: X-ray, CT, and MRI Roles

Imaging strategy depends on the suspected coalition type. For CN coalitions, a 45° oblique x-ray is highly sensitive — the elongated anterior process of the calcaneus extending toward the navicular (“anteater nose sign”) is pathognomonic. For TC coalitions, x-rays are unreliable — the C-sign (a continuous arc from talus to sustentaculum) and talar beaking are suggestive but inconsistent. CT is the gold standard for bony TC coalitions and surgical planning, while MRI catches cartilaginous and fibrous coalitions and rules out alternative diagnoses (such as osteochondral lesions of the talus, accessory navicular syndrome, or stress fractures).

• 45° oblique x-ray — first-line for CN coalition; sensitivity ~75%.
• Lateral x-ray (weight-bearing) — look for talar beaking, C-sign, ball-and-socket ankle.
• Harris-Beath axial view — classic projection for the middle subtalar facet; rarely ordered now.
• CT scan (1 mm slices, multiplanar) — gold standard for bony coalitions and surgical planning.
• MRI — identifies cartilaginous/fibrous coalitions; assesses cartilage damage at the subtalar joint; rules out OLT and stress fractures.

Differential Diagnosis

Because the symptoms of a tarsal coalition mimic many common adolescent foot complaints, the differential is wide. We work hardest to rule in or rule out the conditions below before settling on a coalition diagnosis.

• Flexible flatfoot — arch reforms on tiptoe; subtalar motion preserved.
• Posterior tibial tendon dysfunction (PTTD) — uncommon in adolescents; medial pain with weak inversion.
• Accessory navicular syndrome — isolated medial mid-foot pain with palpable bony prominence.
• Sever’s disease (calcaneal apophysitis) — heel pain in 8–12 year olds; tenderness at the apophysis.
• Osteochondral lesion of the talus (OLT) — deep ankle pain after a sprain; MRI required for diagnosis.
• Stress fracture (calcaneus, navicular, metatarsal) — activity-related point pain.
• Chronic ankle instability — ligamentous laxity; treated as an isolated diagnosis until coalition is ruled out.
• Juvenile idiopathic arthritis — rare; bilateral hindfoot synovitis; rheumatology referral.

Non-Operative Treatment

Non-operative care is the right starting point for nearly every newly diagnosed tarsal coalition. About 50–75% of adolescents respond to a structured 8–12 week conservative trial, especially if the coalition is small (<50% of joint surface), if there is little subtalar arthritis on MRI, and if the family commits to a full course. The goals are to quiet the inflammation, unload the rigid joint, and rebuild kinetic chain strength so the rest of the limb compensates.

1. Activity modification — pause running, jumping, and lateral cutting sports for 6–8 weeks; substitute swimming and cycling.
2. NSAIDs for 7–14 days under pediatric guidance to control inflammation.
3. CAM walker boot or below-knee cast × 4–6 weeks for acute flares; immobilization is the single most powerful conservative tool.
4. Custom orthotics with a deep heel cup, medial post, and University of California Berkeley Lab (UCBL)-style hindfoot control to unload the subtalar joint.
5. Topical pain control — Doctor Hoy’s Natural Pain Relief Gel on the sinus tarsi area 2–3 times daily during flare. (Affiliate disclosure: Amazon Associates, tag biernact-20.)
6. Supportive sneaker insole — PowerStep Pinnacle Maxx with rearfoot post is our daily-wear bridge while custom orthotics are being made.
7. Physical therapy — gentle range-of-motion, peroneal stretching, intrinsic strengthening, and gait retraining.

Surgical Treatment Options

Surgery is indicated when 8–12 weeks of structured conservative care has failed or when the patient cannot tolerate the activity restrictions. The choice of operation depends on coalition type, size, the presence of subtalar arthritis, and the patient’s age and activity goals. Coalition resection with interposition (fat graft, EDB muscle, or bone wax) is the procedure of choice when the coalition is small, the joint is healthy, and the patient is skeletally immature.

• CN coalition resection with EDB or fat interposition — 80–90% good-to-excellent results in adolescents; restores subtalar motion and relieves pain.
• TC coalition resection — appropriate when the coalition is <50% of the joint surface and there is no subtalar arthritis. Outcomes 70–85%.
• Subtalar arthrodesis (fusion) — for large coalitions (>50%), end-stage subtalar arthritis, or failed resection. Eliminates pain at the cost of subtalar motion.
• Triple arthrodesis (subtalar + talonavicular + calcaneocuboid) — reserved for adults with multi-joint arthritis; rare in adolescents.
• Subtalar arthroereisis — an emerging adjunct that can be combined with CN resection in patients with significant valgus deformity.
• Concurrent calcaneal lengthening osteotomy (Evans) — added when residual flatfoot deformity persists after resection.

Recovery After Coalition Surgery

Recovery after coalition resection follows a predictable timeline. Most adolescents are non-weightbearing in a splint or cast for 2 weeks, then transition to a CAM boot for 4–6 weeks, with full activity returning around 4–6 months. Early gentle subtalar motion is critical to prevent reformation of the bony bridge — this is one of the few orthopedic surgeries where excessive rest is actually harmful.

1. Weeks 0–2: Posterior splint, non-weightbearing, elevation 23 hours/day.
2. Weeks 2–6: CAM boot, progressive weightbearing, gentle subtalar range-of-motion exercises 4 times daily.
3. Weeks 6–10: Stiff sneaker, full weightbearing, formal physical therapy with peroneal stretching and intrinsic strengthening.
4. Weeks 10–16: Return to gym class, light running, jumping rope; resume sports drills without contact.
5. Months 4–6: Full return to sports, including cutting and jumping; custom orthotic worn long-term to maintain motion gains.

Outcomes & Long-Term Prognosis

Outcomes after coalition resection are excellent in well-selected adolescents. Modern series report 80–90% good-to-excellent outcomes for CN resection and 70–85% for TC resection at 5+ years, with most patients returning to full pre-symptom sports participation. The biggest predictors of failure are large coalitions (>50% of joint surface), pre-existing subtalar arthritis on MRI, severe valgus heel deformity, and operating on patients who are already skeletally mature with degenerative changes.

Long-term, even successful resections produce subtle radiographic changes — mild residual deformity, a small amount of subtalar arthritis, or partial recurrence of bony bridging. The clinical question that matters is whether the patient is functioning at their target activity level without pain. The vast majority are. Patients who fail resection still have the salvage option of subtalar fusion at any future date, which eliminates pain reliably even if it does sacrifice motion.

🚨 When to See a Podiatrist Now

Call our office at (810) 206-1402 if your child has recurrent ankle sprains, a stiff flatfoot that does not reform an arch on tiptoe, post-activity ache that builds over hours, restricted side-to-side foot motion, or pain that persists despite arch supports and rest. Earlier diagnosis means easier treatment and better long-term outcomes.

The Most Common Mistake We See

The most common mistake we see is dismissing an adolescent’s recurrent ankle sprains as ligamentous laxity without a single advanced imaging study. Standard 3-view ankle x-rays miss roughly 30% of tarsal coalitions, and CN coalitions specifically need a 45° oblique view that is rarely included in routine series. Patients spend 12–24 months in PT for “chronic ankle instability” before someone orders an MRI and finds the bridge. By the time they reach our clinic, secondary arthritis at the subtalar joint may have already started to develop — lowering the success rate of resection.

The second most common mistake is over-immobilizing post-operatively. Coalition resection is one of the few foot operations where you have to start motion early; otherwise the body fills the gap with new bone and the coalition reforms. We start gentle subtalar motion at week 2 and have patients in formal PT by week 6. The third is failing to address residual hindfoot valgus — a kid who has a successful CN resection but still walks on a flat, valgus foot will continue to overload the lateral column. Adding a calcaneal lengthening osteotomy or arthroereisis at the index surgery makes a meaningful difference.

Frequently Asked Questions

At what age does a tarsal coalition usually become symptomatic?

CN (calcaneonavicular) coalitions typically become symptomatic between ages 8 and 12, when the cartilaginous bridge ossifies. TC (talocalcaneal) coalitions become symptomatic later, ages 12 to 16. About 20% of patients are not diagnosed until adulthood, when chronic ankle problems or post-traumatic flares finally trigger advanced imaging.

Will my child grow out of a tarsal coalition?

No — coalitions do not resolve on their own. The bridge becomes more rigid with age as it ossifies. However, about 50–75% of children respond well to non-operative treatment (immobilization, orthotics, activity modification, PT), and many maintain that improvement long-term. Surgery is reserved for those who fail conservative care.

Can a tarsal coalition be diagnosed on x-ray alone?

CN coalitions can usually be seen on a 45° oblique x-ray (the “anteater nose sign”), but TC coalitions and fibrous coalitions are unreliable on x-ray alone. CT is the gold standard for bony coalitions and surgical planning, while MRI is best for fibrous and cartilaginous coalitions and ruling out other causes of pain.

What sports can my child play after coalition surgery?

Most adolescents return to full sports participation 4 to 6 months after coalition resection, including soccer, basketball, lacrosse, dance, and running. Custom orthotics worn long-term help maintain the motion gains and protect the subtalar joint from over-pronation. Patients who undergo subtalar fusion can still run, hike, and play recreational sports but are typically advised to avoid high-level cutting sports.

What’s the difference between resection and fusion?

Resection removes the abnormal bony bridge while preserving the subtalar joint, allowing the joint to move again. Fusion intentionally locks the subtalar joint to eliminate painful motion. Resection is preferred for small coalitions, healthy joints, and skeletally immature patients. Fusion is reserved for large coalitions, end-stage arthritis, failed resections, or adults with multi-joint disease.

Is tarsal coalition hereditary?

Yes — inheritance is autosomal dominant with variable expressivity. A parent with a coalition has roughly a 50% chance of passing it to each child, but the child may be asymptomatic for life. About half of patients with a tarsal coalition have a coalition in the opposite foot as well, often the same subtype.

The Bottom Line

A tarsal coalition is a congenital bony bridge between two of the back-foot bones that becomes symptomatic in adolescence as it ossifies, producing a stiff, painful, often flat foot with recurrent ankle sprains. The single most useful exam test is the toe-raise: a coalition flatfoot does not reform an arch on tiptoe. Standard x-rays miss many cases — if clinical suspicion is high, get the CT or MRI. Most adolescents respond to immobilization and orthotics, with resection or fusion reserved for refractory cases. If your teen has chronic foot pain or recurrent sprains, schedule a focused exam with our team and we’ll get the right diagnosis.

Adolescent Foot Pain Not Going Away?

Dr. Tom Biernacki and our board-certified team have diagnosed and treated tarsal coalitions in athletes ages 8–25 across our Howell and Bloomfield Hills offices. Same-week appointments available.

Call (810) 206-1402 · Howell & Bloomfield Hills, MI

Sources

1. Mosca VS. Subtalar coalition in pediatrics. Foot Ankle Clin. 2015;20(2):265-281. PubMed
2. Cohen BE, Davis WH, Anderson RB. Success of calcaneonavicular coalition resection in the adult population. Foot Ankle Int. 1996;17(9):569-572. PubMed
3. Lemley F, Berlet G, Hill K, Philbin T, Isaac B, Lee T. Current concepts review: tarsal coalition. Foot Ankle Int. 2006;27(12):1163-1169. PubMed
4. Khoshbin A, Bouchard M, Wasserstein D, et al. Outcomes of tarsal coalition resection in pediatric patients. J Pediatr Orthop. 2015;35(4):408-414. PubMed
5. Mubarak SJ, Patel PN, Upasani VV, Moor MA, Wenger DR. Calcaneonavicular coalition: treatment by excision and fat graft. J Pediatr Orthop. 2009;29(5):418-426. PubMed

Frequently Asked Questions

When should I see a podiatrist?

If symptoms persist past 2 weeks, affect your normal activity, or are accompanied by red-flag symptoms (warmth, redness, swelling, inability to bear weight).

What does treatment cost?

Most diagnostic visits and conservative treatments are covered by Medicare and major insurers. Out-of-pocket costs vary by your specific plan.

How quickly can I get an appointment?

Most non-urgent cases see us within 5 business days. Urgent cases (sudden pain, possible fracture) typically same or next business day.

What is Foot pain?

Foot pain is a common foot/ankle condition that affects mobility and quality of life. Understanding the underlying cause is the first step in successful treatment. Our podiatrists at Balance Foot & Ankle perform a hands-on biomechanical exam, review your activity history, and use diagnostic imaging when appropriate to identify the root cause—not just treat the symptom. Many patients have been told to “rest and ice” without a deeper diagnostic workup; our approach is different.

Symptoms and warning signs

Common signs of foot pain include pain that worsens with activity, morning stiffness, swelling, tenderness when palpated, and difficulty bearing weight. If you experience sudden severe pain, inability to walk, visible deformity, numbness or color change, contact our office the same day or visit urgent care—these can signal a more serious injury such as a fracture, tendon rupture, or vascular compromise. Diabetics with any foot wound should seek same-day care.

Conservative treatment options

Most cases of foot pain respond to non-surgical care: structured rest, supportive footwear changes, custom orthotics, targeted stretching and strengthening protocols, anti-inflammatory medications when medically appropriate, and in-office procedures such as ultrasound-guided injections. We also offer advanced therapies including MLS laser therapy, EPAT/shockwave, regenerative injections, and image-guided procedures. Treatment is sequenced from least invasive to most invasive, and we explain the rationale at every step.

When is surgery considered?

Surgery is reserved for cases that fail 3-6 months of well-structured conservative care, when there is structural pathology (severe deformity, complete tear, advanced arthritis), or when imaging shows damage that will not heal without intervention. Our surgeons have performed 3,000+ foot and ankle procedures and prioritize minimally-invasive techniques whenever appropriate. We discuss recovery timelines, return-to-activity milestones, and realistic outcome expectations before any procedure is scheduled.

Recovery timeline and prevention

Recovery from foot pain varies based on severity and chosen treatment path. Conservative cases often improve within 4-8 weeks with consistent adherence to the protocol. Post-procedural recovery may range from a few days (in-office procedures) to several months (reconstructive surgery). Long-term prevention involves footwear assessment, activity modification, structured strengthening, and regular check-ins with your podiatrist if you have a history of recurrence. We provide written home-exercise plans and digital follow-up support.

In-Office Treatment at Balance Foot & Ankle

If home treatment isn’t providing relief for your tarsal coalition michigan podiatrist, our podiatry team at Balance Foot & Ankle can help with same-day evaluations and advanced in-office care.