Plantar fasciitis accounts for the majority of heel pain cases in adults, but the heel is a surprisingly complex structure, and at least a dozen distinct conditions can produce pain there. The cause matters because treatments differ sharply depending on whether the problem originates in a ligament-like band on the sole of the foot, a tendon at the back of the heel, a compressed nerve, or an underlying inflammatory disease. Sorting out where your pain falls in that landscape is the first step toward getting it to stop.
Plantar Fasciitis, the Most Common Culprit
The plantar fascia is a thick, fibrous band that runs along the bottom of your foot from the heel bone to the base of the toes. When it becomes irritated, inflamed, or starts to break down at the cellular level, the result is a sharp or stabbing pain right at the underside of the heel. This condition, plantar fasciitis, involves both inflammation and degeneration of the fascia and is the single most frequent reason people seek help for heel pain.1Europe PMC / Biomedicines. Plantar Fasciitis Pathophysiology and the Potential Role of Mesenchymal Stem Cell-Derived Extracellular Vesicles as Therapy
The hallmark symptom is pain with your first steps in the morning or after sitting for a long time. It tends to ease once you get moving, then flare again after prolonged standing or at the end of a long day on your feet. The pain is usually concentrated at the inner edge of the heel, right where the fascia attaches to the bone. People sometimes describe it as stepping on a pebble or a piece of glass.
Researchers have found that several physical characteristics are associated with plantar heel pain: a higher body mass index, reduced range of motion when pulling the foot upward at the ankle, and weaker muscles on the outer side of the ankle and in the toes. Interestingly, foot arch shape, general joint looseness, and even the amount of time spent standing at work did not clearly separate those with heel pain from those without it in one study.2PubMed Central. Musculoskeletal and activity-related factors associated with plantar heel pain That finding challenges the common assumption that flat feet or high arches inevitably lead to heel trouble. Ankle stiffness and calf tightness appear to matter more.
The Heel Spur Myth
Many people who get an X-ray for heel pain are told they have a heel spur, a small bony growth on the underside of the heel bone. The natural assumption is that the spur is jabbing into soft tissue and causing the pain. The evidence, however, tells a different story. Studies have found that neither the shape nor the size of a heel spur correlates with the severity of symptoms before treatment.3PubMed. Relationship and Classification of Plantar Heel Spurs in Patients With Plantar Fasciitis Heel spurs show up frequently on the X-rays of people who have zero pain, and many people with severe pain have no spur at all.
The current thinking is that spurs are a byproduct of long-term mechanical stress on the fascia, not the source of pain themselves. They may signal that other conditions are at play, but removing a spur surgically is rarely the answer.4PubMed. The conundrum of calcaneal spurs: do they matter? If your doctor mentions a spur on imaging, it is worth understanding that the spur is more of a marker of stress than a direct pain generator.
Pain at the Back of the Heel
Not all heel pain is on the bottom. Pain at the back of the heel, where the Achilles tendon meets the bone, points to a different set of problems. Insertional Achilles tendinopathy is one of the most common. It involves degeneration of the tendon fibers right at their attachment point, sometimes accompanied by calcium deposits within the tendon and inflammation of the bursa (a small fluid-filled cushion) between the tendon and the bone.5Europe PMC / Foot & Ankle International. Current Concepts Review Update: Insertional Achilles Tendinopathy The cause is usually a combination of mechanical overload, repetitive stress, and age-related tendon changes. Runners, walkers, and people who suddenly ramp up their activity are frequent candidates.
A related condition is Haglund’s deformity, sometimes called “pump bump.” This is a bony enlargement on the back of the heel bone. When the bump is prominent enough, it presses against the soft tissues overlying it, especially when shoes with rigid heel counters push into that area. The resulting friction can inflame the retrocalcaneal bursa and produce swelling and pain.6Orthopedic Clinics of North America. Haglund’s Deformity and Retrocalcaneal Bursitis Switching to shoes with softer or lower heel counters can make a noticeable difference, though more stubborn cases sometimes need additional treatment.
When a Nerve Is the Problem
Nerve-related heel pain is frequently missed. The symptoms overlap heavily with plantar fasciitis, so people sometimes go through months of stretching and orthotics without improvement because the real issue is a compressed nerve.
The most commonly overlooked nerve problem in the heel involves Baxter’s nerve, which is the first branch of the lateral plantar nerve running deep inside the foot. When this nerve gets pinched, it produces chronic, burning pain along the inner heel that can be difficult to distinguish from fascia pain. It can occur on its own or alongside plantar fasciitis, which makes diagnosis even trickier.7PubMed. Baxter’s nerve: the hidden culprit of chronic heel pain Clues that point toward Baxter’s nerve entrapment include burning or tingling sensations, pain that does not follow the classic morning-stiffness pattern of fasciitis, and tenderness in a slightly different spot than the typical fascia attachment point.8PubMed Central. Plantar Fasciitis with Chronic Baxter’s Neuropathy Causing Hindfoot Pain – A Case Report
Tarsal tunnel syndrome is another nerve entrapment worth knowing about. The tarsal tunnel sits behind the inner ankle bone, and the tibial nerve passes through it. If the nerve gets compressed there, the result is numbness, burning, and painful tingling that can radiate into the heel and the sole of the foot.9PubMed Central. An Update on Posterior Tarsal Tunnel Syndrome Some people describe it as an electrical sensation. Tarsal tunnel syndrome can be caused by swelling after an ankle injury, cysts, varicose veins near the tunnel, or even an extra muscle that takes up space in the area.10The FASEB Journal. Incision of the flexor retinaculum of the foot fails to relieve symptoms of tarsal tunnel syndrome due to presence of a variant flexor digitorum accessorius longus (FDAL) muscle If your heel pain comes with numbness, tingling, or a sense of electric shocks radiating along the sole, nerve compression is high on the list of suspects.
Stress Fractures of the Heel Bone
The calcaneus, or heel bone, is the largest bone in the foot and absorbs substantial force every time you take a step. Repetitive loading can cause tiny cracks known as stress fractures, particularly in people who have recently increased their activity level, have weakened bones, or spend long hours on their feet. These fractures are notoriously easy to miss. Standard X-rays often look normal in the early weeks, and the symptoms, mainly pain and swelling in the heel, overlap with plantar fasciitis and other soft-tissue problems. An MRI is frequently needed to confirm the diagnosis after initial imaging comes back clean.11Europe PMC / Cureus. Delayed Diagnosis of Calcaneal Stress Fracture: A Case Report
A calcaneal stress fracture typically produces pain that worsens with weight-bearing and does not follow the “worst in the morning, better with walking” pattern of plantar fasciitis. If squeezing the sides of the heel bone together with your hands reproduces the pain (the “squeeze test”), a stress fracture is worth investigating. Treatment usually involves rest, a walking boot, and a gradual return to activity once the bone has healed.
Heel Pain in Children and Adolescents
Growing kids get heel pain for a reason that does not apply to adults. In children roughly between the ages of eight and fourteen, the growth plate at the back of the heel bone has not yet fused. Repetitive pulling from the Achilles tendon on that soft, growing cartilage can inflame it, producing a condition called calcaneal apophysitis, or Sever’s disease.12Elsevier / Clinics in Podiatric Medicine and Surgery. Physical Therapy and Rehabilitation of the Foot and Ankle in the Athlete / Calcaneal apophysitis (Sever disease) It is especially common in active kids who play sports that involve running and jumping. The pain is usually at the back or sides of the heel and gets worse with activity. The good news is that it resolves on its own once the growth plate closes, though rest, heel cups, and stretching can manage symptoms in the meantime.
Fat Pad Changes
Underneath the heel bone sits a specialized pad of fat compartments designed to absorb shock. The heel pad dissipates a significant fraction of the energy returned from the ground at each step.13Journal of Experimental Biology. Rethinking the evolution of the human foot: insights from experimental research As people age, or after repeated steroid injections into the heel, that fat pad can thin out or lose its structure. The result is a bruise-like ache concentrated directly under the heel bone that feels different from the arch-side pain of fasciitis. Studies comparing normal and atrophic heel pads found that thinned pads produce a high but narrow pressure peak, concentrating force over a smaller area.14PubMed Central. Investigations into the fat pads of the sole of the foot: heel pressure studies There is no way to regrow lost heel fat, so management focuses on cushioning with gel heel cups, padded shoes, and avoiding hard surfaces.
Inflammatory and Autoimmune Diseases
Heel pain can be an early or prominent symptom of systemic inflammatory conditions, particularly a group of diseases collectively called spondyloarthritis. These include psoriatic arthritis and ankylosing spondylitis, among others. In these diseases, the immune system attacks the entheses, the spots where tendons and ligaments attach to bone. The heel has two major entheses (the Achilles attachment and the plantar fascia attachment), making it the most common site for this type of inflammation.15Annals of the Rheumatic Diseases. A randomised, multicentre, double-blind, placebo-controlled trial of etanercept in adults with refractory heel enthesitis in spondyloarthritis: the HEEL trial
In a study of patients with spondyloarthritis who had heel pain, MRI confirmed inflammation or structural damage at the entheses in roughly 84% of cases.16PubMed Central. Magnetic resonance imaging characteristics in patients with spondyloarthritis and clinical diagnosis of heel enthesitis: post hoc analysis from the phase 3 ACHILLES trial This kind of heel pain tends to be worse at rest (especially at night and in the early morning), affects both feet more often than mechanical causes do, and resists the usual physical-therapy approaches. If your heel pain is accompanied by low back stiffness that improves with movement, psoriasis, or a family history of autoimmune conditions, it is worth discussing the possibility of an inflammatory disease with your doctor. The treatment path involves managing the underlying immune disorder, not just addressing the heel.
Rare and Unexpected Causes
Occasionally, heel pain traces back to something unusual. Bone infections (osteomyelitis) in the heel can arise from penetrating injuries, and on imaging they can look surprisingly similar to tumors or other bone conditions.17PubMed Central. Chronic Calcaneal Osteomyelitis Due to a Retained Coral Fragment: An Unusual Cause of Heel Pain Gout can flare in the heel, though the big toe joint is more common. Tumors, both benign and malignant, can develop in or near the calcaneus. These rare causes are mentioned not to alarm you but to explain why persistent heel pain that does not respond to several months of conservative treatment deserves further imaging and evaluation. A standard X-ray may look fine while an MRI reveals an entirely different picture.
How Heel Pain Is Diagnosed
Most clinicians start with a physical exam: pressing on different spots around the heel, checking ankle flexibility, and observing how you walk. The location of tenderness, the timing of pain, and whether symptoms include numbness or burning help narrow the differential. For straightforward cases of plantar fasciitis, imaging is not always necessary up front.
When symptoms persist or the picture is unclear, ultrasound and MRI are the main tools. On ultrasound, an inflamed plantar fascia appears thickened, with loss of its normal layered structure and sometimes increased blood flow visible on Doppler imaging. MRI can reveal similar thickening and signal changes in the fascia, as well as swelling in adjacent soft tissue and bone marrow that ultrasound may miss.18PubMed Central. Imaging of plantar fascia disorders: findings on plain radiography, ultrasound and magnetic resonance imaging MRI is also the tool of choice for spotting stress fractures, nerve pathology, and inflammatory changes in the bone. If your doctor orders imaging, it is usually because the diagnosis is uncertain or treatment has stalled, not because the condition is necessarily more serious.
Treatment Approaches That Actually Help
For plantar fasciitis and most mechanical heel pain, the evidence supports starting simple. Orthotic insoles of any type tend to improve pain. Stretching the plantar fascia specifically (pulling back on the toes to stretch the arch) shows limited benefit in the first month but meaningful improvement over longer periods. Steroid injections can provide short-term relief, and combining them with stretching appears more effective than either alone. However, repeated steroid injections carry a real risk of thinning the fat pad or even rupturing the fascia, so doctors increasingly recommend guiding injections with ultrasound to reduce complications.19PubMed Central. The real risks of steroid injection for plantar fasciitis, with a review of conservative therapies
When conservative measures fail after several months, extracorporeal shockwave therapy (ESWT) is an option. This uses focused pressure waves to stimulate healing in the damaged tissue. In one study, patients who received shockwave therapy showed progressive improvement at three, six, and twelve weeks.20PubMed Central. Effectiveness of shockwave therapy in the treatment of plantar fasciitis For posterior heel problems like insertional Achilles tendinopathy, eccentric exercises (slowly lowering the heel off a step) are a cornerstone of therapy, sometimes supplemented by bracing or, in resistant cases, surgery to remove damaged tendon tissue or a Haglund’s bump.
Nerve entrapment conditions tend to require different strategies. Rest and anti-inflammatory medications may help, but if there is a structural cause for the compression, such as a cyst or extra muscle in the tarsal tunnel, surgical release is sometimes necessary.
How Footwear Affects the Heel
Shoes matter, though the relationship is more nuanced than “supportive shoes good, flat shoes bad.” Minimalist shoes have gained popularity, but research shows they substantially increase loading on the Achilles tendon. In one study of recreational runners, peak Achilles tendon force was significantly larger in minimalist shoes compared to maximalist (heavily cushioned) shoes, and cumulative tendon loading per mile was higher in minimalist shoes than in both maximalist and conventional options.21Comparative Exercise Physiology. Effects of minimalist and maximalist footwear on Achilles tendon load in recreational runners Transitioning to minimalist shoes also increased peak Achilles tendon force and loading rate, even after twelve weeks of gradual adaptation.22PubMed. Effects of 12-week transition training with minimalist shoes on Achilles tendon loading in habitual rearfoot strike runners
This does not mean minimalist shoes are inherently dangerous, but it does mean that switching to them places more demand on the Achilles tendon and heel. If you already have insertional Achilles tendinopathy or are recovering from plantar fasciitis, a heavily cushioned shoe with some arch support is generally the safer bet until symptoms resolve. For Haglund’s deformity, look for shoes with a soft or absent rigid heel counter, since that bump at the back of the shoe is often the primary irritant.
Psychological Factors and Pain Sensitization
Chronic heel pain does not exist in a vacuum. Research has found that psychological and social factors are meaningfully tied to how severe heel pain becomes and how much it limits daily life. In a study comparing people with plantar heel pain to those with other types of foot pain, the heel-pain group was more likely to have a systemic disease and showed higher levels of kinesiophobia, which is the fear of movement due to anticipated pain. They also had worse morning pain and more pain with standing.23PubMed Central. The association of demographic, psychological, social and activity factors with foot health in people with plantar heel pain Sensitization, where the nervous system amplifies pain signals beyond what the tissue damage alone would produce, was also associated with greater symptom severity.
This does not mean heel pain is “in your head.” It means that when pain persists for months, the nervous system can start turning up the volume knob, making the same level of tissue irritation feel worse. Addressing that amplification through graded exercise, understanding pain science, and managing fear of movement can help break the cycle. If you have been dealing with heel pain for a long time and feel like your symptoms are disproportionate to what the imaging shows, pain sensitization is a real, physiological phenomenon worth discussing with your provider rather than dismissing or pushing through.