Retrocalcaneal & Posterior Achilles Bursitis

Quick answer

There are two distinct bursae at the back of the heel, both prone to inflammation:

• Retrocalcaneal bursa — sits between the Achilles tendon and the heel bone. Inflammation here causes deep pain at the back of the heel, often confused with insertional Achilles tendinitis.
• Subcutaneous (posterior) calcaneal bursa — sits between the Achilles tendon and the skin, just under the surface. Inflammation here causes a tender, sometimes visible swelling — the classic “pump bump” inflammation.

Both forms commonly coexist with Achilles tendinopathy and Haglund’s deformity, and they share triggers: stiff-backed shoes, running on hills, tight calves, and overuse.

What’s actually happening

A bursa is a small fluid-filled sac that reduces friction between moving structures. The two bursae behind the heel cushion the Achilles tendon as it moves over the heel bone and as it pushes against the back of the shoe.

When repetitive friction or pressure exceeds what the bursa can handle, it becomes inflamed — thickened, painful, and sometimes swollen. The lining produces extra fluid, the area becomes warm and tender, and any motion that loads the area hurts.

How to recognize it

Retrocalcaneal bursitis (deep)

• Deep pain at the back of the heel, just in front of the Achilles
• Tenderness when pinching the front of the Achilles tendon insertion
• Worse going uphill or with deep dorsiflexion
• Often coexists with insertional Achilles tendinitis — and the two can be hard to separate clinically

Posterior subcutaneous bursitis (“pump bump”)

• Visible swelling at the back of the heel
• Red, warm, tender lump just below the skin
• Pain with shoe pressure — the lump rubs against shoe backs
• Often associated with a Haglund’s deformity — a bony prominence that pushes the bursa against the shoe

Why this happens

Common contributors:

• Stiff-backed shoes — pumps, dress shoes, certain athletic shoes — push directly on the bursa
• Haglund’s deformity — a bony bump on the back of the heel that increases shoe pressure
• High arches (cavus foot) — heel sits more vertically, increasing posterior pressure
• Tight calves and Achilles — increase tendon-on-bursa friction
• Running on hills — repeated forced dorsiflexion compresses the retrocalcaneal bursa
• Sudden increases in training
• Inflammatory arthritis (rheumatoid, ankylosing spondylitis) can predispose to retrocalcaneal bursitis

Diagnosis

This is typically a clinical diagnosis:

• Physical exam — distinguish the two bursae by location of tenderness; look for swelling, redness, warmth, and any bony prominence
• X-rays — assess for Haglund’s deformity, insertional calcific changes in the Achilles, and joint disease
• Ultrasound — visualizes the bursa directly, useful when diagnosis is unclear or for guided injection
• MRI — for severe or refractory cases, evaluates the Achilles and surrounding tissues

Treatment

Conservative care (effective for most)

• Footwear changes — backless or open-back shoes, soft-backed athletic shoes, avoid stiff dress shoes during flares
• Heel lifts — small heel raises (1/4 to 1/2 inch) take tension off the Achilles and reduce posterior pressure
• Padding — silicone or felt pads cushion the bump from shoe contact
• Ice after activity
• NSAIDs short-term for inflammation
• Calf and Achilles stretching — gentle, sustained
• Eccentric Achilles loading — for coexisting tendinopathy
• Activity modification — reduce hill work and high-mileage running during a flare
• Physical therapy — strengthening, flexibility, gait analysis

Most cases resolve over 4–8 weeks of consistent care.

When more is needed

• Walking boot for 2–4 weeks for severe cases — sometimes dramatically helpful
• Cortisone injection — used cautiously. The injection should be into the bursa, not the Achilles tendon, because steroids weaken tendons. Generally limited to 1–2 injections total, separated in time.
• Shockwave therapy — emerging option for chronic cases

Surgery

Reserved for refractory cases:

• Bursectomy — removal of the inflamed bursa
• Haglund’s resection — removal of the bony prominence that’s driving the pressure
• Achilles debridement — for coexisting insertional tendinopathy
• Recovery typically 6–12 weeks, with progressive return to activity

Bottom line

Heel bursitis is a common, usually self-limited problem driven primarily by footwear and biomechanics. Switching out of stiff-backed shoes, adding heel lifts, and addressing tight calves resolves the great majority of cases. Persistent symptoms warrant imaging to look for Haglund’s deformity or coexisting Achilles tendinopathy — and surgery is available but rarely needed.