Morton’s neuroma is a compressive neuropathy of the common plantar digital nerve, most commonly occurring in the third web space, followed by the second and then the fourth.
- Also called intermetatarsal neuroma, intermetatarsal neuritis, plantar interdigital neuroma, interdigital neuroma, interdigital neuralgia, interdigital neuritis and plantar digital neuralgia
- It has no histological evidence of a true neuroma with axonal degeneration and collagen proliferation.
- It is the most common compressive neuropathy after carpal tunnel syndrome.
- Affects 88 in every 100,000 women and 50 in every 100,000 men presenting to primary care in UK.
- Diagnosis can reliably be made based on clinical presentation and testing.
- US is equally effective as MRI or even superior in some studies when diagnosing Morton's Neuroma.
The effectiveness of non-surgical interventions for common plantar digital compressive neuropathy (Morton’s neuroma): a systematic review and meta-analysis - Journal of Foot and Ankle Research volume 12, Article number: 12 (2019) - Matthew et al
Conclusion - Corticosteroid injections and manipulation/mobilisation are the two interventions with the strongest evidence for pain reduction, however high-quality evidence for a gold standard intervention was not found. Although the evidence base is expanding, further high quality RCTs are needed.
- Manipulation / mobilisation - (involving distraction and plantarflexion of the metatarsophalangeal joints and mobilisation of other foot and ankle joints as required) Showed reduction in pain.
- Wider footwear and metatarsal padding - helpful in 32% patients
- Extracorporeal shockwave therapy - no change in symptoms
- Varus/valgus foot wedge - no benefit
- Corticosteroid injection - combined steroid and anaesthetic injection helpful in reducing pain.
- Sclerosing injection - using ethyl alcohol or phenol were helpful.
- Radiofrequency ablation - helpful
- Cryoneurolysis - helpful
- Botox injection - helpful
What factors predict the need for further intervention following corticosteroid injection of Morton's neuroma? - Foot and Ankle Surgery, Volume 22, Issue 1, March 2016, Pages 9-11 - Mahadevan et al
- Larger neuromas and younger patients were predictors of the need for further intervention but not gender.
- People with neuroma with a transverse diameter larger than 5 mm had worse pain scores by 6 months post injection compared to those with a smaller neuroma.
