Pain at the back of the heel most commonly comes from irritation of the Achilles tendon, the thick band of tissue connecting your calf muscle to your heel bone. But several other structures sit in that same small area, and pinpointing which one is causing trouble determines what actually helps. The most likely culprits are Achilles tendinitis, bursitis, a bony bump called Haglund’s deformity, or, in kids and teens, a growth plate condition called Sever’s disease.
Achilles Tendinitis and Tendinosis
The Achilles tendon handles enormous force every time you walk, run, or push off your toes. When you suddenly increase your activity level, switch to different shoes, or spend more time on your feet than usual, the tendon can become inflamed. This is tendinitis: an acute, short-term inflammatory problem affecting the tendon cells. You’ll typically feel a stiff, burning pain just above the back of your heel, especially first thing in the morning or after sitting for a while. It often loosens up with gentle movement, then flares again with sustained activity.
If that early inflammation goes untreated for weeks or months, it can progress into tendinosis. At this stage, the inflammatory cells are replaced by degenerative cells, and the tendon itself starts to break down rather than simply being irritated. The tendon may thicken visibly, and the pain becomes more persistent. This distinction matters because treatments that work well for fresh inflammation, like rest and ice, are less effective once degeneration has set in. Tendinosis typically requires a structured rehabilitation program to rebuild the tendon’s strength.
Pain from tendinitis or tendinosis usually shows up about two centimeters above where the tendon attaches to the heel bone, in the narrowest part of the tendon. If your pain is right at the attachment point on the bone itself, that’s called insertional tendinopathy and can overlap with other conditions described below.
Bursitis Behind the Heel
Tucked between your Achilles tendon and your heel bone sits a small fluid-filled sac called the retrocalcaneal bursa. Its job is to reduce friction, but when it gets irritated, it swells and produces a deep, aching pain right at the back of the heel. This is the most common type of heel bursitis. A second type, subcutaneous calcaneal bursitis, involves a bursa between the skin and the tendon, producing a more superficial tenderness.
Bursitis symptoms include swelling and warmth around the heel, tenderness when you press into the area, and pain that gets worse when you stand on your toes. The skin around your heel may also change color slightly. Because bursitis and Achilles tendinitis cause pain in nearly the same spot, they can be hard to tell apart without imaging. In fact, they often occur together. If your pain feels deep and is accompanied by visible puffiness on both sides of the tendon, bursitis is a strong possibility.
Haglund’s Deformity (Pump Bump)
Some people develop a bony enlargement on the heel bone right where the Achilles tendon attaches. This growth, called Haglund’s deformity, creates a hard bump you can see and feel through the skin. It’s sometimes called a “pump bump” because rigid-backed shoes like high heels press directly against it, making the pain significantly worse. But any shoe with a stiff heel counter, including dress shoes, work boots, or ice skates, can aggravate it.
The bump itself isn’t dangerous, but it can irritate the surrounding bursa and tendon, creating a chain reaction of inflammation. If you notice a visible lump at the back of your heel along with redness and swelling that flares up with certain footwear, Haglund’s deformity is worth investigating.
Sever’s Disease in Kids and Teens
If your child or teenager complains about heel pain, especially during or after sports, the most likely explanation is Sever’s disease (calcaneal apophysitis). It’s extremely common between ages 8 and 14, when growth spurts cause bones to grow faster than the muscles and tendons can keep up. The growth plate at the back of the heel becomes irritated from the pull of the Achilles tendon.
A doctor can diagnose it with a simple physical exam by applying gentle pressure to the heel to locate the pain. No imaging is usually needed. The condition resolves on its own once the growth plate closes, but reducing activity, icing after sports, and wearing supportive shoes can help manage pain in the meantime.
How to Tell What’s Going On
Location is the biggest clue. Pain a couple of inches above your heel bone points toward Achilles tendinitis or tendinosis. Pain right at the bone, especially with a visible bump, suggests Haglund’s deformity or insertional tendinopathy. Deep pain with swelling on both sides of the tendon leans toward bursitis. Pain in an active child during a growth spurt is most likely Sever’s disease.
When physical examination alone isn’t enough, both ultrasound and MRI are highly accurate for evaluating the Achilles tendon. Ultrasound has a particular advantage: it can image the tendon while you move your ankle, making it easier to distinguish partial tears from simple thickening. MRI provides a more complete picture of the surrounding structures, including the bursa, and can help rule out other causes.
Exercises That Rebuild the Tendon
For Achilles tendinopathy specifically, the most well-studied rehabilitation approach is a program of eccentric heel drops, where you slowly lower your heel below the level of a step. The original protocol, developed in 1998, calls for three sets of 15 repetitions done twice a day, seven days a week, for 12 weeks. You do the exercise first with a straight knee to target the larger calf muscle, then repeat with a slightly bent knee to target the deeper muscle underneath. That adds up to 180 repetitions a day.
If 180 reps sounds like a lot, it is. Starting with fewer and gradually building up works fine. The key is consistency over the full 12 weeks. The exercise should produce mild discomfort but not sharp pain. Over time, the controlled loading stimulates the tendon to lay down stronger, more organized tissue, essentially reversing the degenerative process of tendinosis.
Other Approaches That Help
Footwear changes can make a meaningful difference. For runners or people on their feet all day, shoes with a moderate heel-to-toe drop of 8 to 12 millimeters reduce strain on the Achilles tendon and calf muscles compared to flat or minimalist shoes. If rigid shoe backs are aggravating a Haglund’s bump, switching to open-backed shoes or using heel pads to lift the foot slightly above the shoe’s pressure point can provide immediate relief.
For pain that hasn’t responded to rest and exercise after several months, shockwave therapy is an option with solid evidence behind it. A typical course involves five sessions spaced one week apart. In one study, before treatment began, fewer than one in ten patients reported no limitations in physical activity. After five sessions, three out of four patients had no limitations, and eight weeks after completing treatment, nearly nine in ten were fully active. Painkiller use dropped from 22% before treatment to zero eight weeks after completion.
Signs of Something More Serious
A complete Achilles tendon rupture feels very different from the gradual onset of tendinitis. It typically happens during a sudden push-off movement, like sprinting or jumping, and produces a sharp pop or snap at the back of the ankle. You may feel like someone kicked you in the heel. Walking becomes immediately difficult, and you won’t be able to rise onto your toes on the affected foot.
One simple check: if someone squeezes your calf muscle while you’re lying face down, your foot should point downward slightly because the tendon connects those two structures. If your foot doesn’t move at all, the tendon may be torn. A complete rupture requires prompt medical evaluation, as treatment decisions (surgical repair versus guided rehabilitation) depend on timing and the extent of the injury.