Neuroma: Summary & Treatment Modalities
Definition:
A neuroma is a benign enlargement or thickening of a nerve, typically due to perineural fibrosis and nerve degeneration. The most common type in the foot is Morton’s neuroma, affecting the interdigital nerve, usually between the third and fourth metatarsal heads.
Pathophysiology:
- Repetitive mechanical stress (tight shoes, high heels, pronation)
- Entrapment at anatomical narrow points (deep transverse metatarsal ligament)
- Nerve irritation → perineural fibrosis, edema, and demyelination
- Histology shows features of a traumatic neuroma (fibrosis, axonal sprouting, Schwann cell proliferation)
Clinical Presentation:
- Forefoot pain (burning, tingling, sharp)
- Plantar paresthesia radiating to adjacent toes
- Pain worsens with walking, tight shoes; relieved by removing shoes
- “Pebble-in-the-shoe” sensation
- Positive Mulder’s click or compression test
Imaging/Diagnosis:
- Clinical diagnosis is primary
- Ultrasound: High sensitivity; can detect neuroma >5 mm
- MRI: Useful for surgical planning; T2-weighted images show soft tissue mass
- Diagnostic injection (lidocaine/steroid) may confirm diagnosis and relieve symptoms
Treatment Modalities:
Conservative (First-Line):
- Shoe modifications: Wider toe box, low heels
- Orthotics: PowerStep Orthotics, Spenco Rx Arch Support - Lightweight, 240+lbs Heavy Duty High Arch Support
- Metatarsal pads or bars to offload nerve - Dr. Jill's Gel Metatarsal pads (reusable), ZenToes Metatarsal Pads.
- NSAIDs
- Activity modification
Interventional:
- Corticosteroid injections
- Reduces inflammation; may be repeated up to 3 times/year
- Alcohol sclerosing injections
- 4–7% ethanol can ablate the nerve chemically; mixed evidence, better for small neuromas
- Radiofrequency ablation or cryotherapy
- Minimally invasive neuromodulation; outpatient procedures
Surgical:
- Neuroma Excision
- Transection and removal of the affected nerve segment
- May result in permanent numbness
- Recurrence or stump neuroma is a risk
- Nerve Decompression (Release)
- Release of the deep transverse intermetatarsal ligament
- Preserves the nerve; preferred in some cases to avoid sensory loss
- May be performed via open or minimally invasive technique
Prognosis:
- Conservative treatment is successful in ~50–80% of early cases
- Surgery has ~80–90% success but carries risk of numbness, scar sensitivity, or recurrence
- Earlier intervention improves long-term outcomes
