Morton's Neuroma

What is an Intermetatarsal Neuroma?

An intermetatarsal neuroma (IMN) is any irritative process of the common digital nerve branch that supplies the toes . It most frequently involves the nerve that supplies sensation to adjacent sides of the third and fourth toes, but can also affect other toes of the foot. A neuroma is not cancerous and is not a true tumour but a reactive, degenerative process such as a scar. Therefore, a neuroma is a benign enlargement of the nerve.

Symptoms

Besides pain, you may also experience numbness and burning of your foot. Symptoms are aggravated by walking in shoes and relieved by removing shoes, resting and massaging the foot. Pain that occurs at rest may suggest that the neuroma is worsening.

Causes

Intermetatarsal neuroma occurs in all adult age groups and is most prevalent among females. Although the exact etiology of IMN is unclear, several factors contribute to its occurrence. High-heeled shoes, trauma, inflammatory conditions such as arthritis, and repetitive trauma from stresses incurred in occupational and recreational activities are several of these factors. Any condition that causes constriction or irritation of the nerve can lead to the development of an intermetatarsal neuroma.

Diagnosis

Diagnosis is made by a thorough history of symptoms, physical examination and diagnostic procedures. Classic symptoms include pain with walking. This pain may manifest itself as burning, shooting, stabbing or radiating. Relief of pain by removing the shoes and massaging the area is another typical symptom. A thorough physical examination of the lower extremity is performed. Special attention is directed to the sensory portion of the neurological exam. The patient's description of symptoms provided can often be reproduced upon physical examination. A painful, movable mass perceptible to touch that replicates the pain is a strong sign of a neuroma. Other diagnostic signs are a postivie Mulders click, postive confirmation on a ultrasound scan or the utilisation of a diagnostic injection of anaesthetic into the effected intermetatarsal area.

Treatment

The goal of treatment is to reduce or eliminate symptoms. Although some patients may not receive complete relief, it is expected that the vast majority will gain significant improvement from therapy. Treatment may be surgical or nonsurgical. Nonsurgical treatment is often attempted before surgical intervention. Conservative treatment for an intermetatarsal neuroma usually includes modifying shoes, orthoses or cortisone injections. These conservative therapies may provide complete, partial or no relief of symptoms. The decision to surgically intervene is based on your symptoms, the judgment of your Consultant Podiatric Surgeon and your preference. A neurectomy or surgical removal of a neuroma is performed when conservative treatment proves ineffective.

Postoperative Management

Most patients who undergo neurectomy usually experience a progressive ability to resume normal activity during the postoperative period. Any surgical procedure carries with it potential for complications. Neuroma surgery may be complicated by recurrence of pain, haemotoma (bleeding), a painful scar or infection and occasionally a recurrence of the neuroma. Conclusion The management of intermetatarsal neuroma includes many treatment options. Your podiatric surgeon may consider conservative therapy before surgical intervention and discuss all aspects of care that are available to you.