Morton's neuroma
Exam Tips
- In OSCEs, localise pain precisely by asking the patient to point with one finger; Morton’s pain is usually maximal in an intermetatarsal web space, not directly over a metatarsal head.
- Demonstrate Mulder manoeuvre correctly (plantar thumb pressure plus transverse metatarsal squeeze) and state that a negative test does not exclude the diagnosis.
- Always mention footwear history (high heels/tight toe box) and activity triggers, then immediate relief with shoe removal/massage as high-yield clues.
- State red flags/differentials explicitly: persistent rest/night pain, systemic symptoms, or atypical neurology should prompt imaging and broader work-up.
- For anatomy revision, review a forefoot cross-sectional figure of the deep transverse intermetatarsal ligament and common digital plantar nerve in the third web space (standard MSK foot anatomy diagrams).
Definition
Morton’s neuroma is a compressive neuropathy of a common plantar digital nerve, most often in the third intermetatarsal space, causing neuropathic forefoot pain (metatarsalgia). Despite the name, it is not a true neoplasm; histology is usually perineural fibrosis with nerve degeneration and demyelination due to chronic irritation/entrapment.
Pathophysiology
Current models are complementary rather than mutually exclusive: repetitive forefoot microtrauma, local ischaemia, intermetatarsal bursitis with nerve adherence, and mechanical entrapment beneath the deep transverse intermetatarsal ligament. Chronic loading (especially in tight toe-box or high-heeled footwear) increases plantar pressure across metatarsal heads, driving perineural fibrosis and altered nerve conduction, which explains burning/shooting pain and intermittent paraesthesia. The third web space is most commonly affected because of local biomechanical stress and interdigital nerve anatomy; bilateral or multi-space disease can occur.
Risk Factors
- Female sex (approximately 4:1 female-to-male ratio), typically age 40-60 years
- Regular use of narrow toe-box, tight, or high-heeled shoes
- High-impact activities (running, jumping, dancing, athletics)
- High-arched foot biomechanics and other forefoot loading abnormalities
- Associated forefoot deformity (for example hallux valgus/lesser toe deformities) increasing intermetatarsal pressure
Clinical Features
Symptoms
- Intermittent forefoot pain (often 3rd web space), classically sharp, stabbing, burning, or shooting
- Paraesthesia, numbness, or cramping radiating to adjacent toes
- Sensation of a 'pebble' or 'lump' in the shoe on weight bearing
- Pain triggered by walking/activity or constrictive footwear, relieved by shoe removal and forefoot massage
- May progress to persistent pain; some patients report rest/night pain
Signs
- Focal tenderness on palpation/compression of the affected intermetatarsal space
- Mulder sign: palpable/audible click with transverse metatarsal squeeze plus plantar pressure (absence does not exclude diagnosis)
- Possible sensory change in involved toes (may be absent on examination)
- Contributory biomechanical findings on foot exam (arch type, hindfoot alignment, toe deformities, callosities, gait abnormalities)
Investigations
Management
Lifestyle Modifications
- Footwear modification: avoid high heels, thin soles, and narrow/constrictive toe boxes
- Use over-the-counter metatarsal pad positioned just proximal to metatarsal heads
- Reduce aggravating impact activity (for example running/jumping) during flares
- If persistent after about 3 months, refer for orthotist-led metatarsal dome orthosis
Pharmacological Treatment
Simple analgesia
- Paracetamol 1 g orally every 4-6 hours when required (maximum 4 g/day)
Useful for pain control but does not treat underlying entrapment.
NSAIDs (oral/topical, short courses)
- Ibuprofen 400 mg orally three times daily with food (maximum 2.4 g/day on prescription)
- Naproxen 250-500 mg orally twice daily (maximum 1 g/day)
- Diclofenac 1% gel, apply 2-4 times daily to painful area
Check contraindications: peptic ulcer disease/GI bleeding risk, CKD, heart failure, ischaemic heart disease, cerebrovascular disease, uncontrolled hypertension, NSAID-sensitive asthma, anticoagulant use, and pregnancy (avoid particularly from 20 weeks; contraindicated in 3rd trimester). Consider gastroprotection (for example omeprazole 20 mg once daily) if GI risk is elevated.
Specialist injection therapy
- Ultrasound-guided corticosteroid injection, e. g. methylprednisolone acetate 20-40 mg with local anaesthetic (specialist setting)
- Ultrasound-guided alcohol sclerosing injections (specialist protocols vary)
Corticosteroid injections can improve symptoms but repeated injections are limited by fat-pad atrophy, skin depigmentation, capsular damage, and toe deviation risk. Alcohol injections may cause significant transient pain and have variable long-term durability.
Surgical / Interventional
- Interdigital neurectomy (excision of symptomatic nerve segment)
- Decompression via deep transverse intermetatarsal ligament release (with or without neurolysis)
- Surgery is usually considered after failed conservative and injection-based treatment
Complications
- Persistent or recurrent pain (including stump neuroma after surgery)
- Sensory loss/numbness in adjacent toes (postoperative or disease-related)
- Injection-related complications: plantar fat-pad atrophy, skin discolouration, severe post-injection pain, metatarsophalangeal instability/toe deviation
- Postoperative complications: wound infection, hypersensitive or keloid scar, complex regional pain syndrome, stiffness
Prognosis
Symptoms are unlikely to resolve spontaneously without intervention. Many patients improve with footwear/orthotic strategies and activity modification; injection therapy offers moderate short- to medium-term benefit, while surgery generally has the highest success in refractory cases but carries complication and recurrence risks.
Sources & References
âś…NICE Guidelines(1)
- Morton's neuroma[overview]