J Korean Orthop Assoc.  2017 Aug;52(4):298-304. 10.4055/jkoa.2017.52.4.298.

Morton's Neuroma

• Young KW
• Lee HS

• KMID: 2387787
• DOI: http://doi.org/10.4055/jkoa.2017.52.4.298

Abstract

Morton's neuroma, also known as interdigital neuroma, is a common cause of forefoot pain. It is a compressive neuropathy of the interdigital nerve, which is compressed by the overlying transverse metatarsal ligament. It is not a true tumor. The symptoms are forefoot pain that radiates into the toes, according to the involved nerve branches. Its histological findings are fibrosis around the nerve, demyelination. The clinical diagnosis can be obtained from a detailed history and physical examination, such as the compressive test. Moreover, ultrasonography and magnetic resonance imaging can also be used. Conservative treatment is the common initial treatment modality for interdigital neuroma. Surgical excision or decompression is indicated after a failure of conservative treatments.

Keyword

Morton neuroma; interdigital neuroma; compressive neuropathy; forefoot pain

MeSH Terms

Decompression
Demyelinating Diseases
Diagnosis
Fibrosis
Ligaments
Magnetic Resonance Imaging
Metatarsal Bones
Neuroma*
Physical Examination
Toes
Ultrasonography

Figure

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  Figure 1 Schematic drawing shows plantar nerves of right foot.

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  Figure 2 Schematic drawing shows the neurovascular bundle, just below the deep transverse metatarsal ligament.

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  Figure 3 The pressure is applied in a mediolateral direction with one hand to increase pressure on the tissue between the metatarsal heads. This maneuver results in a significant clicking feeling (the Mulder's sign) and the patient's pain.

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  Figure 4 Ultrasonographic image shows round shaped hypoechoic lesion.

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  Figure 5 Coronal T2-weighted image reveals low signal intense mass (arrow) on second intermetatarsal space.

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  Figure 6 A soft metatarsal pad is added to the insole just proximal to the metatarsal head region, which helps to spread the metatarsal heads to relieve pressure on the nerves.

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  Figure 7 Gross specimen shows enlarged interdigital nerve.

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