Back of Ankle Pain: Causes & Fix 2026 | DPM

Condition	Location	Key Feature	Aggravating Activity	Treatment
Non-insertional Achilles tendinopathy	Tendon body 2–6cm above heel	Morning stiffness; warm-up phenomenon; thickening	Running; jumping; hill training	Eccentric calf raises (Alfredson); PT; PRP; rarely surgery
Insertional Achilles tendinopathy	Tendon at calcaneal insertion	Pain at bone insertion; calcification on X-ray	Stiff-heeled shoes; incline running	Heel lift; open-back shoes; eccentric training (modified); ESWT
Retrocalcaneal bursitis	Deep to Achilles at heel; Haglund’s bump	Two-finger squeeze positive; fullness at heel sides	Stiff heel counter; dress shoes	Open-back shoes; heel lift; injection; surgical bursa excision
FHL tendinitis	Posterior ankle → big toe	Triggering/locking big toe; dancers; posterior pain	Plantarflexion; relevé; running push-off	Rest; PT; injection; FHL tendon release
Os trigonum syndrome	Posterior lateral ankle (behind fibula)	Forced plantarflexion pain; ballet dancer; soccer player	Forced plantarflexion; soccer kick	Injection; activity mod; surgical excision if refractory
Posterior ankle impingement	Posterior ankle soft tissue or osteophyte	Pain at end-range plantarflexion; osteophyte on CT	Ballet; soccer; downhill running	PT; injection; arthroscopic posterior debridement

Achilles Tendinopathy Type	Location	Eccentric Heel Drop Protocol	Footwear Modification
Non-insertional (mid-tendon)	2–6 cm above calcaneus	Standard Alfredson: 3 × 15 straight + bent knee on step edge, both directions, twice daily	Moderate heel lift; avoid barefoot initially
Insertional	At calcaneus bone attachment	Modified: avoid drop below neutral (no step-edge decline); range limited to neutral to plantarflexion only	Heel lift critical; open-back shoes; avoid heel counter pressure

Quick answer: Ankle Pain Back has multiple potential causes including mechanical, neurological, vascular, and inflammatory. The most common causes we identify are overuse, ill-fitting shoes, and biomechanical imbalance. Red flags requiring urgent evaluation: warmth/redness (infection), inability to bear weight (fracture), and unilateral swelling without injury (DVT). Call (810) 206-1402.

The Posterior Ankle Structures

The back of the ankle contains three main pain generators: the Achilles tendon (the most powerful tendon in the body, connecting the calf to the heel), the retrocalcaneal bursa (a fluid-filled sac between the Achilles and the calcaneus), and the posterior ankle joint capsule with its accessory bones (os trigonum). Distinguishing between these requires knowing exactly where the pain is and what aggravates it.

Achilles Tendinopathy

The most common posterior ankle pain diagnosis. Mid-portion tendinopathy (2–6cm above the heel insertion) presents with tendon thickening, morning stiffness, and pain with the first steps that improves with warm-up but worsens with prolonged activity. Insertional tendinopathy (pain at the heel insertion itself) has a different character — more constant, worsened by direct pressure from shoe counters. Both require eccentric calf strengthening as the cornerstone of treatment; insertional tendinopathy also benefits from heel lifts to offload the insertion.

Retrocalcaneal Bursitis

Inflammation of the bursa between the Achilles and the posterior calcaneus. Pain is specifically at the Achilles-heel junction rather than along the tendon belly. Often associated with Haglund deformity (a bony prominence on the posterosuperior calcaneus — the “pump bump”). Soft heel counter shoes or open-back shoes, ice, and corticosteroid injection are effective. Severe cases with Haglund deformity may require surgical calcaneal osteotomy.

Os Trigonum Syndrome

An accessory bone posterior to the talus that compresses during ankle plantarflexion (pointing the foot). Deep posterior ankle pain specifically with plantar flexion activities — ballet en pointe, soccer shooting, jumping. Corticosteroid injection is effective short-term; surgical excision resolves chronic cases. See our dedicated os trigonum page for full detail.

Frequently Asked Questions

How do I know if my posterior ankle pain is the Achilles or the bursa? Achilles tendinopathy: tenderness along the tendon belly, 2–6cm above heel. Retrocalcaneal bursitis: tenderness specifically at the junction where the tendon meets the heel, often with pain from shoe counter pressure.

Can I run with posterior ankle pain? Mild Achilles tendinopathy at 3/10 that improves with warm-up — modifiable running with reduced volume. Retrocalcaneal bursitis and os trigonum syndrome are more sensitive to load and usually require rest from running during acute phases.

In-Office Treatment at Balance Foot & Ankle

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