Sinus Tarsi Syndrome: Anatomy, Causes, Diagnosis, and Treatment

Medically reviewed by Dr. Tom Biernacki, DPM — Board-Certified Podiatric Surgeon — Balance Foot & Ankle, Howell & Bloomfield Hills, MI. Last updated April 2026.

Sinus tarsi syndrome — pain and tenderness at the sinus tarsi (the canal between the talus and calcaneus on the lateral hindfoot, just anterior to the lateral malleolus) — is a distinct clinical entity that accounts for a significant proportion of persistent lateral ankle pain following ankle sprains, and is frequently overlooked in patients treated for ‘chronic ankle instability’ or ‘peroneal tendinopathy’ who continue to have lateral hindfoot pain despite appropriate treatment of those conditions.

Anatomy and Pathophysiology

The sinus tarsi is a cone-shaped canal running obliquely between the posterior and middle subtalar joint facets, containing the interosseous talocalcaneal ligament (ITCL), cervical ligament, fat tissue, a neurovascular bundle, and proprioceptive nerve endings. The sinus tarsi is the primary passive stabilizer against subtalar inversion — the ITCL is the most commonly injured ligament in ankle inversion injuries, though it receives far less clinical attention than the lateral ankle ligaments (ATFL, CFL). Causes: post-traumatic (ankle sprain with ITCL injury — the most common cause in 70% of cases); inflammatory arthritis (RA, psoriatic arthritis, gout producing synovitis within the sinus tarsi); flatfoot deformity (pronation chronically stretches the sinus tarsi structures); ganglion cyst within the canal. Pathology: scar tissue, fibrosis, and synovitis within the sinus tarsi canal produce local pain and subtalar stiffness. Clinical diagnosis: point tenderness directly over the sinus tarsi (a fingertip palpation just anterior to the lateral malleolus in the depression between the talus and calcaneus); pain reproduced with subtalar inversion and eversion; the lateral ankle ligaments are intact on stress testing (distinguishing from ATFL instability). Diagnostic confirmation: subtalar injection of local anesthetic under ultrasound guidance into the sinus tarsi — elimination of pain with injection is both diagnostic and therapeutic.

Treatment

Conservative: cortisone injection into the sinus tarsi under ultrasound guidance (provides lasting relief in 60–70% of cases); subtalar orthotic control (medial wedge to reduce pronation strain on the sinus tarsi); physical therapy for subtalar proprioception. Surgical: arthroscopic debridement of sinus tarsi fibrosis and synovitis when conservative management fails after 6 months — 80% satisfactory outcomes; subtalar arthroscopy allows visualization and debridement of the interosseous ligament complex. Dr. Biernacki at Balance Foot & Ankle evaluates lateral hindfoot pain with diagnostic ultrasound and performs sinus tarsi injection and subtalar arthroscopy for sinus tarsi syndrome. Call (810) 206-1402 at our Bloomfield Hills or Howell office.

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In-Office Treatment at Balance Foot & Ankle

If home care isn’t resolving your your foot or ankle concern, a visit with a board-certified podiatrist is the fastest path to accurate diagnosis and a personalized plan. At Balance Foot & Ankle Specialists, Dr. Tom Biernacki, Dr. Carl Jay, and Dr. Daria Gutkin offer same-day and next-day appointments at both our Howell and Bloomfield Hills offices. We perform on-site diagnostic ultrasound, digital X-ray, conservative care, advanced regenerative treatments, and minimally invasive surgery when indicated.

Call (810) 206-1402 or request an appointment online. Most insurance plans accepted, including Medicare, Blue Cross Blue Shield, Aetna, Cigna, and United Healthcare.

Frequently Asked Questions

When should I see a podiatrist?

See a podiatrist for any foot or ankle pain that persists more than 2 weeks, doesn’t improve with rest, limits your daily activities, or is accompanied by swelling, numbness, or skin changes. People with diabetes or circulation problems should see a podiatrist regularly even without symptoms.

What does a podiatrist treat?

Podiatrists diagnose and treat all conditions of the foot, ankle, and lower leg including plantar fasciitis, bunions, hammertoes, toenail problems, heel pain, nerve pain, diabetic foot care, sports injuries, fractures, and foot deformities — both surgically and non-surgically.

What can I expect at my first podiatry visit?

Your first visit includes a full medical history, physical examination of your feet and gait, and in-office diagnostic imaging if needed (X-rays, ultrasound). We’ll discuss your diagnosis and create a personalized treatment plan. Most visits take 30–45 minutes.

Need Treatment at Balance Foot & Ankle?

Dr. Tom Biernacki, Dr. Carl Jay, and Dr. Daria Gutkin see patients at our Howell and Bloomfield Township offices.

Book Online or call (810) 206-1402

Most Common Mistake We See

The most common mistake we see is: Waiting too long before seeking care. Fix: any foot pain lasting more than 4 weeks, or any sudden severe symptom, deserves a professional evaluation rather than more rest.

Warning Signs That Need Same-Day Care