Plantar fasciitis accounts for the majority of heel pain complaints that bring people to a doctor, but it is far from the only explanation. The heel bone sits at the bottom of the body’s entire load-bearing structure, and the tissue surrounding it includes tendons, nerves, fat pads, and growth plates that can each become a source of pain on their own. Getting the cause right matters because treatments that help one condition can be useless or even harmful for another.
Plantar Fasciitis and Why the Name Is Misleading
The plantar fascia is a thick band of connective tissue that runs along the sole of your foot, connecting the heel bone to the base of your toes. When it becomes painful, the condition is called plantar fasciitis, a name that implies inflammation. But tissue samples from patients with the condition consistently show something different: chronic degenerative changes rather than true inflammatory processes.1PubMed Central. Plantar Fasciitis: An Updated Review That distinction is more than academic. Treatments aimed purely at reducing inflammation, like repeated cortisone injections, may temporarily dull pain without addressing the underlying tissue breakdown.
The hallmark symptom is a sharp, stabbing pain on the bottom of the heel that is worst with your first steps in the morning or after sitting for a long time. The pain usually eases after a few minutes of walking as the tissue loosens, then returns after prolonged standing or when you stand up again after resting. This pattern is distinctive enough that most clinicians can make the diagnosis on symptoms alone, but it can also lead to tunnel vision. Other conditions mimic the same pattern closely enough that misdiagnosis happens more often than you might expect.
Calcaneal Spurs and the Myth of the “Bone Poking Your Foot”
X-rays of people with heel pain often reveal a small bony growth on the underside of the heel bone, and it is tempting to assume this spur is what hurts. Research does confirm a significant association between plantar fasciitis and calcaneal spur formation, though whether the spur actually causes the pain is a separate question entirely.2PubMed. Plantar fasciitis and the calcaneal spur: Fact or fiction? Plenty of people have spurs on X-ray with zero heel pain, and plenty of people with severe heel pain have no spur at all. The spur likely forms as the body’s response to chronic pulling and stress at the fascia’s attachment point, making it a consequence of the problem rather than the problem itself.
This matters for treatment decisions. Surgically removing a heel spur rarely resolves symptoms on its own, and knowing that the spur is a marker for prolonged tissue stress rather than the direct pain generator helps set realistic expectations.
Achilles Tendinopathy and Pain at the Back of the Heel
Pain at the back of the heel, rather than the bottom, usually points to the Achilles tendon. The two main forms are classified by location: insertional tendinopathy, which occurs right where the tendon attaches to the heel bone, and midportion tendinopathy, which affects the tendon a few centimeters higher up.3PubMed Central. Achilles Tendinopathy: Current Concepts about the Basic Science and Clinical Treatments Although they share a name, they behave somewhat differently. Insertional tendinopathy tends to involve more structural changes at the heel bone itself, including calcification and bony deformity that are significantly more common than in the midportion type.4PubMed Central. Differences at the Achilles Insertion Between Adults with Insertional and Midportion Achilles Tendinopathy as Observed Using Ultrasound
Insertional Achilles tendinopathy can be tricky because the pain sits close to the heel and may be confused with plantar fasciitis, especially when both conditions coexist. A simple way to distinguish them at home: plantar fasciitis hurts most when you press on the bottom center of your heel, while Achilles problems typically hurt when you squeeze the back of the heel or when you push off during walking.
Haglund’s Deformity and Retrocalcaneal Bursitis
If you feel a hard, painful bump on the upper back of your heel, especially one that gets irritated by stiff-backed shoes, you may be dealing with Haglund’s deformity. This is an excessive bony prominence on the back-upper part of the heel bone. The bump itself can press against the bursa (a small fluid-filled sac that cushions the Achilles tendon), causing swelling and inflammation known as retrocalcaneal bursitis.5Orthopedic Clinics of North America. Haglund’s Deformity and Retrocalcaneal Bursitis Rigid heel counters on shoes and high heels make it worse by pushing directly against the prominence. People with high arches or feet that roll inward tend to be more susceptible.
Switching to shoes with softer, lower heel counters or open-backed shoes often provides significant relief. When conservative measures fail, surgery to shave down the bony bump is an option, though recovery takes weeks to months.
Nerve Entrapment That Masquerades as Plantar Fasciitis
Some heel pain is neurological, not structural, and this category gets missed more than it should. Posterior tarsal tunnel syndrome occurs when the tibial nerve or one of its branches gets compressed as it passes through a narrow tunnel on the inner side of the ankle. The symptoms include numbness, burning, and tingling along the heel and sole.6PubMed Central. An Update on Posterior Tarsal Tunnel Syndrome Anything that physically reduces the space inside that tunnel, from a swollen tendon to a cyst to scar tissue, can trigger it.
An even more frequently missed diagnosis involves Baxter’s nerve, a small branch of the tibial nerve that runs along the inner heel. Baxter’s nerve entrapment is considered the most common neurological cause of heel pain, yet it is frequently misdiagnosed as plantar fasciitis because the pain location overlaps almost perfectly.7PubMed. Baxter’s nerve: the hidden culprit of chronic heel pain The key clue is heel pain that does not improve with standard plantar fasciitis treatment after several months, or pain accompanied by burning and tingling sensations that extend across the sole. Anatomical mapping of the tarsal tunnel confirms that Baxter’s nerve entrapment appears to be the leading neurological cause of heel pain syndrome.8PubMed Central. Clinical-anatomic mapping of the tarsal tunnel with regard to Baxter’s neuropathy in recalcitrant heel pain syndrome: part I If your heel pain has lasted months and hasn’t responded to stretching, orthotics, or injections, nerve entrapment deserves serious consideration.
Heel Fat Pad Problems
Beneath the heel bone sits a specialized pad of fat that acts as a shock absorber. Unlike fat elsewhere in the body, this pad has a honeycomb-like internal structure that disperses impact forces. When it thins or breaks down, you lose that cushioning, and the heel bone sits closer to the ground with less protection. Fat pad atrophy is associated with aging, rheumatological conditions, diabetes, and obesity.9PubMed Central. What do we actually know about a common cause of plantar heel pain? A scoping review of heel fat pad syndrome
Research on the heel fat pad’s mechanical behavior shows that it tends to grow thicker from early childhood into middle adulthood, then thins progressively after middle age.10PubMed. The relationship of heel fat pad thickness with age and physiques in Japanese Beyond just getting thinner, the pad’s mechanical properties change with age, reducing its ability to absorb shock and potentially affecting overall foot function.11PubMed. Changes in functional characteristics of heel fat pad with age Fat pad pain tends to be more diffuse than plantar fasciitis pain, centered squarely under the heel bone rather than slightly forward toward the arch. It often worsens with barefoot walking on hard surfaces. Cushioned heel cups and well-padded shoes are the first line of defense.
Calcaneal Stress Fractures
A stress fracture in the heel bone develops when repetitive impact loads exceed the bone’s ability to repair itself. Unlike a sudden break from a fall, stress fractures build up gradually from accumulated microscopic damage.12PubMed. Stress fractures of the foot and ankle Runners, military recruits, and people who abruptly increase their activity level are most at risk, but calcaneal stress fractures also show up in older adults with weakened bones.
The diagnostic challenge is real. Calcaneal stress fractures overlap in symptoms with nearly every other form of heel pain, and standard X-rays often look completely normal in the early weeks. When clinical suspicion remains high despite negative X-rays, MRI is the recommended next step and can reveal the fracture before it becomes obvious on plain film.13PubMed Central. Delayed Diagnosis of Calcaneal Stress Fracture: A Case Report One distinguishing feature: squeezing the sides of the heel bone typically reproduces the pain of a stress fracture, whereas plantar fasciitis pain is usually provoked by pressing on the bottom of the heel.
Heel Pain in Children
Children and adolescents get heel pain too, but the cause is usually different from anything on the adult list. Sever’s disease, formally called calcaneal apophysitis, is an overuse condition affecting the growth plate in the heel bone. It is an underreported but common pediatric condition, and it can present as pain in one or both heels.14PubMed Central. Sever’s Disease of the Pediatric Population: Clinical, Pathologic, and Therapeutic Considerations The exact injury mechanism is not fully understood, but repetitive stress on the growth plate during periods of rapid growth is the leading theory. It most commonly affects kids between ages 8 and 14, particularly those who are active in sports that involve running and jumping.
Several risk factors have been identified. Children with calcaneal apophysitis tend to have a higher body mass index, greater height, and greater weight compared to their peers. Differences in foot posture and ankle flexibility also play a role, and older children who have been in pain longer tend to report more severe symptoms.15PubMed. Factors Associated with Pain Severity in Children with Calcaneal Apophysitis (Sever Disease) A systematic review of risk factors confirmed that limited ankle flexibility, foot alignment, body mass index, age, sex, and participation in sports all contribute.16BMJ Open. Risk factors and associated factors for calcaneal apophysitis (Sever’s disease): a systematic review The good news is that Sever’s disease resolves on its own once the growth plate closes. In the meantime, reducing activity, heel cushions, and stretching exercises manage the symptoms.
When Heel Pain Signals a Systemic Disease
Heel pain is sometimes the first sign of a systemic inflammatory condition, particularly the group of diseases known as spondyloarthritis, which includes ankylosing spondylitis and psoriatic arthritis. These conditions can cause enthesitis, inflammation at the points where tendons and ligaments attach to bone. The Achilles tendon insertion on the heel bone is one of the most commonly affected sites.
In a registry study of patients with ankylosing spondylitis, about 6% had Achilles tendon enthesitis detectable on physical examination. Those patients had significantly higher disease activity scores and worse functional outcomes over two years of follow-up compared to those without heel involvement. The proportion achieving low disease activity was roughly half that of patients without Achilles enthesitis.17PubMed Central. Achilles enthesitis on physical examination leads to worse outcomes after 2 years of follow up in patients with ankylosing spondylitis from REGISPONSER-AS registry MRI studies of patients with spondyloarthritis and heel enthesitis have also been used to characterize the specific imaging patterns, helping distinguish inflammatory heel pain from mechanical causes.18PubMed Central. Magnetic resonance imaging characteristics in patients with spondyloarthritis and clinical diagnosis of heel enthesitis
If your heel pain is accompanied by morning stiffness in your lower back, swollen toes, or a history of psoriasis, inflammatory arthritis should be on the radar. The treatment pathway is entirely different from that of mechanical heel pain and usually involves disease-modifying medications rather than stretching and orthotics.
Risk Factors That Cut Across Multiple Conditions
Certain factors make you more vulnerable to heel pain regardless of the specific diagnosis. Body weight is the most consistently identified one. A systematic review of factors associated with chronic plantar heel pain found that elevated body mass index in non-athletic populations and the presence of a calcaneal spur were the two strongest associations. Increased weight, older age, reduced ankle flexibility, limited big-toe extension, and prolonged standing all showed evidence of a link.19PubMed. Factors associated with chronic plantar heel pain: a systematic review
Research on patients with painful heel spurs reinforces the weight connection. In one study, the average BMI was substantially higher in people with painful spurs compared to controls, and obesity roughly tripled the odds of having a painful spur rather than a silent one.20PubMed Central. Association of Obesity and Plantar Fasciitis in Patients With Plantar Heel Spurs Foot mechanics also matter. People with very high arches or flat feet place abnormal loads on the heel, and tight calf muscles limit the ankle’s ability to flex upward, which in turn shifts more strain to the plantar fascia and heel pad.
Occupational factors are easy to overlook. Jobs that require hours of standing on hard surfaces, from retail work to factory floors, create the kind of cumulative loading that wears down heel structures over time. Footwear plays a role as well. Research into shoe construction and running biomechanics shows that softer midsoles can reduce impact forces and loading rates, while minimalist shoes tend to increase loading at the ankle and Achilles tendon.21PubMed Central. Systematic Review of the Role of Footwear Constructions in Running Biomechanics: Implications for Running-Related Injury and Performance The transition from heavily cushioned to minimalist footwear should be gradual; jumping in too fast is a well-known trigger for Achilles tendon problems and stress fractures.
Getting the Diagnosis Right
Most heel pain gets diagnosed through a physical exam and patient history, which works well when the presentation is textbook. But when symptoms are ambiguous or treatment is not working, imaging becomes important. Ultrasound has proven highly sensitive and specific for differentiating among common causes of heel pain. A comparative study found that adding a technique called shear wave elastography to standard ultrasound improved diagnostic accuracy for plantar fasciitis to above 93% and for Achilles tendinopathy to nearly 98%.22PubMed Central. Ultrasound imaging and shear wave elastography for the differential diagnosis of heel pain: a comparative cross-sectional study Ultrasound is relatively cheap, widely available, and does not involve radiation, making it a practical first-line imaging choice.
MRI is reserved for cases where ultrasound is inconclusive or when a stress fracture, nerve problem, or bone lesion is suspected. As noted earlier with calcaneal stress fractures, MRI can pick up injuries that plain X-rays miss entirely in the early stages.
Treatment Approaches for the Most Common Causes
For plantar fasciitis specifically, the evidence supports a combination of conservative measures as the starting point. Night splints that hold the foot in a flexed position while you sleep can produce significant short-term improvement in pain scores, though they do not necessarily prevent recurrences in the longer term.23PubMed. The effectiveness of dorsiflexion night splint added to conservative treatment for plantar fasciitis Foot orthotics, whether prefabricated or custom-made, improve function, and studies have found that less expensive prefabricated orthotics perform comparably to more costly custom versions.24PubMed Central. Orthotics Compared to Conventional Therapy and Other Non-Surgical Treatments for Plantar Fasciitis Calf stretching, ice massage, and activity modification round out the first-line approach, and these combined measures resolve symptoms in the majority of people within several months.
When conservative methods stall, two common next steps are corticosteroid injections and extracorporeal shock-wave therapy. A meta-analysis comparing the two found that high-intensity shock-wave therapy provided better pain relief than corticosteroid injections within three months, while low-intensity shock-wave treatment was slightly less effective than injections over the same period. Functional outcomes and recurrence rates were similar between the two.25PubMed Central. Clinical effects of extracorporeal shock-wave therapy and ultrasound-guided local corticosteroid injections for plantar fasciitis in adults A meta-analysis of randomized controlled trials A randomized trial looking at the same comparison found that shock-wave therapy produced lower pain scores at both four weeks and twelve weeks compared to injection.26PubMed Central. Ultrasonography and clinical outcome comparison of extracorporeal shock wave therapy and corticosteroid injections for chronic plantar fasciitis: A randomized controlled trial Corticosteroid injections carry a small risk of weakening the plantar fascia or accelerating fat pad atrophy, so they are generally used sparingly rather than as a repeating treatment.
Rare Causes Worth Knowing About
In uncommon cases, heel pain turns out to be caused by something entirely outside the typical musculoskeletal framework. Primary tumors of the heel bone are rare, but when they do occur, heel pain and localized ankle swelling are the most common presenting symptoms. Because clinicians are understandably unfamiliar with calcaneal tumors, diagnosis can be delayed, leading to worse outcomes.27PubMed Central. Primary tumours of the calcaneus Red flags that warrant further investigation include heel pain that worsens at night without any mechanical trigger, pain that does not respond at all to rest, unexplained swelling, or constitutional symptoms like weight loss and fatigue. These scenarios are unusual, but they are the reason persistent, unexplained heel pain deserves proper workup rather than indefinite self-treatment with stretches and over-the-counter insoles.
Infections of the heel bone, while also uncommon, can occur after puncture wounds, in people with diabetes, or after surgery. Gout, which most people associate with the big toe, occasionally presents in the heel. And referred pain from the lumbar spine, specifically from nerve roots that supply the heel area, can produce symptoms that look like a local heel problem but originate much higher up in the body. When heel pain refuses to fit a clear pattern or does not respond to targeted treatment, thinking beyond the foot itself becomes important.