By Dr. Kayla Wright, DPM
The highest-value clue is not the word “pebble.” It is where the sensation is, what it feels like, and what else happens with it.
Use these clues before naming the condition
| What you notice | More suggestive of |
|---|---|
| Burning/electric pain between toes, tingling or numbness | Morton’s neuroma |
| Broad bruised/aching pain under several metatarsal heads | Mechanical metatarsalgia / forefoot overload |
| Pain under the second toe plus swelling, toe drift, or instability | Plantar plate injury |
| A hard focal skin spot you can see or feel | Callus/corn or plantar wart |
| Focal bone pain after a rapid increase in running/walking | Metatarsal stress injury |
| Sudden puncture history or localized foreign-body sensation | Retained foreign body / local soft-tissue injury |
These are pattern clues—not home diagnostic tests. Conditions overlap, and more than one can be present at once.
1. Morton’s neuroma: the classic “pebble” mimic
Morton’s neuroma is a painful enlargement/irritation of a common digital nerve in the forefoot, most often in the space between the third and fourth metatarsals.
Common features include:
- burning or sharp forefoot pain
- tingling or numbness into adjacent toes
- an electrical or shooting quality
- a feeling that a sock is bunched up under the toes
- the sensation of standing on a pebble or marble
- symptoms worse in tight or narrow shoes
- relief after removing the shoe or massaging the forefoot
Mayo Clinic describes the pain as typically involving the bottom of the forefoot with symptoms that can radiate into the toes. A focused exam may reproduce symptoms by pressing the painful interspace or compressing the forefoot.
But the absence of a palpable “click” does not automatically rule neuroma in or out.
2. Metatarsalgia: pressure pain under the ball of the foot
“Metatarsalgia” is an umbrella term describing pain in the ball of the foot rather than one single disease.
It can feel like:
- a bruise beneath the metatarsal heads
- a stone under the forefoot
- pressure that worsens while standing or walking
- soreness after running or long periods on hard surfaces
Contributors can include high-impact activity, footwear, foot shape, bunions or hammertoes, altered loading, and other conditions. Mayo Clinic also lists stress fractures and Morton’s neuroma among conditions associated with metatarsalgia symptoms.
This is why saying “you have metatarsalgia” should ideally lead to a second question:
What is causing the metatarsal-region pain?
3. Plantar plate injury: an underrecognized cause beneath the second toe
The plantar plate is a strong stabilizing structure beneath the lesser toe joints. Injury most often involves the second metatarsophalangeal joint and can initially look like generic metatarsalgia.
Clues include:
- pain directly under the base of the second toe
- swelling around the joint
- a feeling of fullness or a marble under that area
- the toe beginning to lift, drift, or separate from its neighbor
- reduced ability of the toe to stay planted on the ground
- pain with forefoot loading
A 2025 diagnostic review emphasized that plantar plate injury is frequently underrecognized and overlaps with Morton’s neuroma, bursitis, stress injury, and other causes of forefoot pain.
If the “pebble” seems to sit under the second toe joint rather than between the third and fourth toes, plantar plate pathology deserves consideration.
4. Callus or corn: sometimes the pebble is in the skin
A localized buildup of thickened skin can create a very focal pressure point.
Clues include:
- a hard area that you can see or feel directly
- tenderness exactly at the skin lesion
- pain worst with direct downward pressure
- recurrent thickening in the same location
The underlying reason matters. Simply shaving down a callus without addressing the pressure pattern can allow it to return.
For patients with diabetes, neuropathy, poor circulation, or a history of ulcers, self-cutting calluses is especially risky and should be avoided.
5. Plantar wart: pressure can push it inward
A plantar wart can develop on a weight-bearing area such as the ball of the foot. Because body weight presses it inward beneath a layer of callus, it can feel as though you are stepping on a small object.
Mayo Clinic notes that plantar warts may show:
- a rough growth
- interruption of normal skin lines
- small dark pinpoints from clotted vessels
- callus over the lesion
- tenderness when walking or standing
A wart and a callus are treated differently, so identifying the skin lesion correctly matters.
6. Metatarsal stress injury: do not miss the load-history clue
A stress reaction or stress fracture can begin as forefoot discomfort rather than dramatic trauma.
Concern rises when the sensation appears after:
- a rapid increase in running mileage
- starting a new impact sport
- significantly more walking or hiking
- a change in training surface
- return to activity after a layoff
The pain is often more focal over a metatarsal and tends to worsen with continued impact. Swelling may develop. Early X-rays can be normal in some stress injuries, so persistent focal bone pain deserves evaluation rather than repeated massage of a presumed “neuroma.”
A simple location test that improves the conversation
Before your appointment, try to answer three questions:
1. Can you point to the sensation with one finger?
Between the third and fourth toes: neuroma moves higher on the list. Directly under the second toe joint: plantar plate/metatarsal overload moves higher. A visible skin point: callus/wart/foreign body moves higher.
2. Is the sensation neurological or pressure-like?
Burning, tingling, numbness, electric pain: nerve involvement is more likely. Deep bruise/ache: mechanical or joint loading may be more likely.
3. What makes it better?
Taking off a tight shoe: neuroma or shoe-related compression becomes more plausible. Reducing impact for several days: many mechanical causes may improve, but recurring focal bone pain remains important. Padding around a skin lesion: a focal pressure lesion may be involved.
This is not a substitute for examination, but it gives the clinician better diagnostic information than “my foot hurts.”
How a foot-and-ankle specialist evaluates the sensation
Evaluation may include:
- precise palpation of metatarsal heads and interspaces
- forefoot compression tests
- toe stability / plantar plate testing
- skin examination
- assessment of bunions, hammertoes, arch shape, and loading
- footwear review
- weight-bearing X-rays when bone/joint problems are possible
- ultrasound or MRI when the diagnosis remains uncertain or specific soft-tissue pathology needs clarification
Importantly, imaging should support the clinical question rather than replace it. Morton’s neuroma can be visible on imaging in some people without being the actual pain generator, and several forefoot conditions can coexist.
Frequently asked questions
Does a pebble feeling always mean Morton’s neuroma?
No. It is a classic description of Morton’s neuroma, but metatarsalgia, plantar plate injury, callus, plantar wart, stress injury, and other conditions can produce similar sensations.
Can Morton’s neuroma cause numb toes?
Yes. Burning, tingling, numbness, or radiating pain into adjacent toes makes nerve involvement more likely than a simple pressure callus.
What if I can actually feel a lump under the skin?
A visible or palpable focal lesion raises additional possibilities such as callus, wart, foreign body, cyst, or another soft-tissue condition. Do not assume every palpable lump is a neuroma.
Should I get an X-ray for a pebble sensation?
Not everyone needs imaging. X-rays are useful when fracture, arthritis, alignment problems, or other bone/joint conditions are possible. Ultrasound or MRI may be selected for certain soft-tissue questions.
When should I stop trying shoe changes and get it checked?
Seek evaluation when symptoms persist, worsen, cause numbness, change the position of a toe, produce swelling, limit normal walking, or follow a significant increase in impact activity without improving.
Forefoot pain evaluation in Tempe
The phrase “it feels like there is a pebble under my foot” is diagnostically useful because it narrows the conversation—but the location and companion symptoms determine what should happen next.
Metro Foot & Ankle evaluates Morton’s neuroma and other neuromas, plantar plate problems, metatarsal overload, skin lesions, and sports-related forefoot pain in Tempe and the East Valley. If the sensation keeps returning or is changing the way you walk, request an evaluation.
This article is for general educational purposes and does not replace individualized medical advice, diagnosis, or treatment.
Sources
- Mayo Clinic. Morton neuroma: Symptoms and causes. Updated November 3, 2025. https://www.mayoclinic.org/diseases-conditions/mortons-neuroma/symptoms-causes/syc-20351935 (opens in a new tab)
- Mayo Clinic. Morton neuroma: Diagnosis and treatment. Updated November 3, 2025. https://www.mayoclinic.org/diseases-conditions/mortons-neuroma/diagnosis-treatment/drc-20351939 (opens in a new tab)
- Dixon M, Munir U, Tafti D. Morton Neuroma. StatPearls. Updated July 5, 2026. https://www.ncbi.nlm.nih.gov/books/NBK470249/ (opens in a new tab)
- Mayo Clinic. Metatarsalgia: Symptoms and causes. https://www.mayoclinic.org/diseases-conditions/metatarsalgia/symptoms-causes/syc-20354790 (opens in a new tab)
- Diagnosing Plantar Plate Injuries: A Narrative Review of Clinical and Imaging Approaches. Diagnostics. 2025;15(17):2188. https://pmc.ncbi.nlm.nih.gov/articles/PMC12427879/ (opens in a new tab)
- Mayo Clinic. Plantar warts: Symptoms and causes. https://www.mayoclinic.org/diseases-conditions/plantar-warts/symptoms-causes/syc-20352691 (opens in a new tab)