A sore heel is most often caused by plantar fasciitis, a strain of the thick band of tissue that runs along the bottom of your foot. But the location of the pain, when it strikes, and what it feels like can point to several different conditions, from tendon injuries at the back of the heel to thinning of the natural fat pad underneath it. Understanding where your pain falls helps narrow down what’s going on.
Pain Under the Heel: Plantar Fasciitis
Plantar fasciitis is by far the most common reason for pain on the bottom of the heel. The plantar fascia is a tough band of connective tissue stretching from your heel bone to the base of your toes. It acts like a bowstring supporting your arch. When that tissue is repeatedly overstretched or overloaded, it develops tiny tears and becomes inflamed or degenerates over time.
The hallmark symptom is a sharp or stabbing pain with your first steps in the morning or after sitting for a long time. The pain usually eases once you’ve walked around for a few minutes, but it can return after long periods on your feet. It tends to be worst right at the front edge of the heel bone, where the fascia attaches.
Risk factors include a sudden increase in activity, jobs that keep you standing on hard floors, tight calf muscles, higher body weight, and both very flat and very high arches. Runners and people in their 40s through 60s are especially prone.
Pain at the Back of the Heel: Achilles Tendinitis
If the soreness is at the back of your heel rather than underneath it, the Achilles tendon is the likely culprit. This tendon connects your calf muscles to the heel bone and absorbs force every time you push off the ground. Repeated or intense strain without adequate recovery can irritate it, though sometimes the cause isn’t clear.
Achilles tendinitis can develop in two spots: the middle of the tendon (a few inches above the heel) or right where it inserts into the heel bone. Insertional tendinitis at the heel bone is more common in people who aren’t particularly active and tends to worsen with pressure from the back of a shoe. The tendon weakens with age, which is why weekend athletes and people who ramp up mileage too quickly are especially vulnerable.
Typical symptoms include stiffness and aching after rest, tenderness when you squeeze the tendon, and pain that intensifies with activity like climbing stairs or running.
Heel Fat Pad Syndrome
Your heel has a built-in shock absorber: a specialized pad of fatty tissue that cushions the bone with every step. Over time, that pad can thin out or lose its elasticity, leaving the heel bone closer to the surface and more exposed to impact. This condition is frequently misdiagnosed as plantar fasciitis because it also causes pain under the heel.
The key difference is what the pain feels like and where it lands. Fat pad pain produces a deep, bruise-like ache in the center of the heel, and you can reproduce it by pressing firmly into the middle of the heel pad. Plantar fasciitis pain, by contrast, is typically sharper and concentrated closer to the front of the heel bone.
Several factors accelerate fat pad thinning:
- Age. The fat pad naturally loses volume and elasticity over the years.
- Hard surfaces. Walking or running barefoot on concrete or tile increases impact on the pad.
- Repetitive high-impact activity. Basketball, tennis, volleyball, running, and gymnastics all pound the heel repeatedly.
- Poor footwear. Shoes without adequate heel cushioning force the pad to absorb more shock than it can handle.
- Previous steroid injections. Corticosteroid shots used to treat other foot conditions can cause the fat pad to break down, especially with repeated injections.
- Gait and foot structure. The way your foot distributes weight when you walk affects how unevenly the pad wears down.
Heel Spurs: Less Important Than You Think
Many people assume a bony spur on the heel bone is the source of their pain. In reality, heel spurs are present in roughly 11 to 16 percent of adults who have no heel pain at all. Among people who do have pain under the heel, about half have a visible spur on X-ray, but the spur itself is rarely the problem. Less than 5 percent of people with heel spurs actually experience pain from them.
Spurs form gradually as the body deposits extra calcium where the plantar fascia or Achilles tendon pulls on the bone. They’re more of a marker that the area has been under chronic stress than a direct cause of pain. Treating the underlying soft-tissue problem, whether that’s plantar fasciitis or fat pad thinning, usually resolves the symptoms regardless of whether a spur is present.
Nerve Entrapment
Sometimes heel pain has a neurological source. Tarsal tunnel syndrome occurs when a nerve running along the inside of the ankle gets compressed as it passes through a narrow channel near the ankle bone. The pain can radiate to the bottom of the foot and into the heel, but it feels distinctly different from mechanical causes.
The telltale signs are burning, tingling, numbness, or “pins and needles” sensations rather than the aching or stabbing pain of fascia and tendon problems. You may also notice weakness in the small muscles of your foot. If tapping the inside of your ankle reproduces that tingling or shooting pain, nerve compression is a strong possibility.
Sore Heels in Children
Children between 8 and 12 years old can develop heel pain from a condition called Sever’s disease, which isn’t actually a disease but an irritation of the growth plate in the heel bone. During growth spurts, the heel bone grows faster than the surrounding muscles and tendons, pulling on the growth plate and causing inflammation.
Running, jumping, and sports with studded cleats put extra pressure on the area. Symptoms are generally worse during or right after physical activity. The condition is uncommon after age 15, when the growth plate fuses and hardens into solid bone. Diagnosis is usually straightforward: a doctor can identify it based on symptoms and a physical exam, without needing X-rays or blood tests.
Inflammatory and Systemic Conditions
Most heel pain has a mechanical cause, but persistent or bilateral heel soreness, especially if it comes with stiffness that lasts more than 30 minutes in the morning, can signal an inflammatory condition. Several systemic diseases can present as chronic heel pain:
- Ankylosing spondylitis and related inflammatory arthritis. These conditions cause inflammation where tendons and ligaments attach to bone, and the heel is one of the most common sites. Pain often affects both heels and may be accompanied by lower back stiffness.
- Rheumatoid arthritis. Can cause inflammation in the joints and soft tissues around the heel.
- Gout. Although gout most famously strikes the big toe, uric acid crystals can deposit near the heel and trigger intense pain and swelling.
The distinguishing feature of inflammatory heel pain is that it tends to be worst after prolonged rest, improves with movement, and doesn’t respond well to the usual strategies for mechanical heel pain like stretching and better shoes. If your heel pain has lasted months without improving, is present on both sides, or comes with joint pain elsewhere, an underlying inflammatory condition is worth investigating.
How to Tell Which Cause Fits
Location is your best first clue. Pain under the heel near the front of the heel bone points toward plantar fasciitis. A deep bruise in the center of the heel suggests fat pad problems. Pain at the back of the heel, especially when wearing shoes or pushing off, points to the Achilles tendon. Burning or tingling anywhere in the heel raises the possibility of nerve involvement.
Timing matters too. Pain that’s worst with the first steps of the day and then fades is classic plantar fasciitis. Pain that builds the longer you’re on your feet and worsens on hard surfaces fits fat pad syndrome. Stiffness and aching after rest that improves with gentle movement but flares with intense activity is typical of tendon problems. And pain that never fully goes away, particularly if it’s in both heels, deserves a closer look for systemic causes.