Heel Spurs vs Plantar Fasciitis: Why the X-Ray Misleads

Last updated: · FIVOR

Few things in medicine are as persuasive as seeing the problem. You have heel pain, someone takes an X-ray, and there it is — a bony spike pointing forward from your heel bone. Obvious. It is stabbing you. Remove the spike, remove the pain.

That story is intuitive, visual, and mostly wrong.

What a heel spur actually is

A calcaneal spur is a small bony outgrowth on the heel bone, usually pointing forward along the underside. It forms in response to sustained traction — bone laid down where soft tissue repeatedly pulls on it.

Note what that means: the spur is a consequence of long-term tension, not a random growth. It is a record of load, in the same way a callus is a record of friction. Something has been pulling on that spot for a long time and the bone responded.

That already reframes it. The spur is evidence of a process, not necessarily the cause of your symptoms.

The finding that breaks the story

Two facts, both well established, and together they dismantle the intuitive explanation.

1. Plenty of people have heel spurs and no pain at all. Spurs turn up routinely on X-rays taken for entirely unrelated reasons in people whose heels feel fine. If the spur were the cause, those feet would hurt.

2. Plenty of people have classic heel pain and no spur. The symptoms present identically — sharp first-step pain in the morning, easing as you move — with a completely clean X-ray.

A finding that is present in people without the symptom and absent in people with it cannot be the explanation for the symptom. That is the whole argument, and it is why removing spurs is not the standard treatment.

Why the direction is wrong too

Even the geometry does not support the stabbing story.

Spurs typically develop within the soft tissue, oriented along the line of pull — running forward, roughly parallel to the sole — rather than pointing down into the fat pad like a tack. A structure lying along the direction of tension is not well positioned to stab the tissue around it.

The pain of plantar heel pain is more consistently explained by the state of the fascia itself: degenerated, disorganised collagen at the point where it attaches to the heel. Lemont, Ammirati and Usen (2003) examined tissue from chronic cases and found exactly that — degeneration and fragmentation, with an absence of inflammatory cells — proposing the term fasciosis.

The spur and the pain often share a cause. That does not make one the cause of the other.

Why this matters practically

Three real consequences.

It changes what you treat. If you believe the spur is the problem, the logical treatment is removing it. If you understand the spur as a marker of chronic traction, the logical treatment is addressing the traction — stretching the fascia and the calf, managing load, and loading the tissue progressively. The clinical guideline recommends the second set. Surgery for spurs is not a first-line answer.

It changes what you fear. Being shown a bone spike on a screen is frightening in a way "your collagen is disorganised" is not. People conclude they have permanent structural damage requiring surgery. Knowing that spurs are common in pain-free feet takes a lot of the weight out of that image.

It explains why removing it often does not help. The spur was never doing the damage.

What is actually pulling

If the spur is a record of traction, it is worth asking what has been doing the pulling — and the answer is usually not just the fascia.

Your calf muscles converge into the Achilles tendon, which attaches to the back of the heel bone. Your plantar fascia attaches to the underside of that same bone. They share an anchor, with fibrous continuity around the base of the heel transmitting tension between them.

A tight calf keeps the whole system loaded — and in the Riddle (2003) case-control study, restricted ankle dorsiflexion showed the strongest association of the three identified risk factors, ahead of body weight and hours on your feet.

Which is why the guideline recommends stretching the gastrocnemius and soleus alongside the plantar fascia. Treating only the sore spot leaves the thing generating the tension untouched — and that is a common reason people improve temporarily and then relapse.

When imaging is worth having

None of this means an X-ray is useless. It means the spur is usually not the finding that matters.

Imaging earns its place when the picture does not fit the classic pattern:

  • Pain after a specific traumatic moment, especially with a pop, bruising, or an inability to bear weight — a possible tear or fracture
  • Pain that is worse with continued activity rather than worst in the first steps
  • Numbness, tingling or burning — a nerve pattern, which imaging may or may not help with
  • Night pain that wakes you, unexplained weight loss, or fever — these warrant prompt assessment for reasons unrelated to fascia
  • Symptoms that have not responded to several months of appropriate treatment

The classic presentation — sharp pain in the first steps of the morning, easing within ten or twenty minutes, worst after periods of rest — is usually diagnosed clinically. An X-ray that shows a spur does not confirm it, and one that shows nothing does not rule it out.

What to say at your appointment

If you are shown a spur, two useful questions:

  • "Do people without heel pain also have these?"
  • "If we treated the fascia and the calf and the pain resolved, would the spur still be there?"

The honest answers are yes and yes. Which tells you where the treatment should point.

FAQ

Will my heel spur go away? Probably not, and that is fine. The pain can resolve while the spur remains — which is itself good evidence they are not the same problem.

Should I have it removed? Spur removal is not a first-line treatment. Surgery in this area is reserved for cases that have failed a long course of conservative treatment, and the target is generally the fascia rather than the spur.

Does a spur mean my case is worse? No. It suggests the traction has been going on a while. It does not predict how you will respond to treatment.

Can I feel my spur? People often report feeling a hard lump. Tenderness at the inside of the heel is typical of plantar heel pain generally and does not tell you whether a spur is present.

Sources

  • Lemont H, Ammirati KM, Usen N. Plantar fasciitis: a degenerative process (fasciosis) without inflammation. Journal of the American Podiatric Medical Association, 2003
  • Riddle DL, Pulisic M, Pidcoe P, Johnson RE. Risk factors for plantar fasciitis: a matched case-control study. Journal of Bone and Joint Surgery (Am), 2003
  • Journal of Orthopaedic & Sports Physical Therapy — Heel Pain–Plantar Fasciitis: Revision 2023 (APTA clinical practice guideline)

This article is general education, not medical advice. Heel pain following trauma, or accompanied by numbness, night pain or fever, should be assessed promptly by a qualified clinician.