A Morton?s Neuroma is actually incorrectly termed, with the name suggesting it is a tumour or growth. Rather than a true neuroma it is actually what is called a perineural fibrosis, which means that over time the sheath surrounding the nerve becomes irritated, inflamed, and forms a thickened scar tissue.
Anything that causes compression or irritation of the nerve can lead to the development of a neuroma. One of the most common offenders is wearing shoes that have a tapered toe box, or high-heeled shoes that cause the toes to be forced into the toe box. People with certain foot deformities - bunions, hammertoes, flatfeet, or more flexible feet - are at higher risk for developing a neuroma. Other potential causes are activities that involve repetitive irritation to the ball of the foot, such as running or court sports. An injury or other type of trauma to the area may also lead to a neuroma.
Symptoms of interdigital neuroma typically manifest as a sharp, burning or tingling sensation in the forefoot. The pain radiates toward the lesser toes and is aggravated by shoe wear. The pain is relieved when the shoe is removed and the forefoot is massaged. Sometimes the symptoms involve specific toes.
The exact cause of Mortons neuroma can often vary between patients. An accurate diagnosis must be carefully made by the podiatrist through thorough history taking and direct questioning to ensure all possible causes are addressed. The podiatrist will also gather further information about the cause through a hands on assessment where they will try to reproduce your symptoms. A biomechanical and gait analysis will also be performed to assess whether poor foot alignment and function has contributed to your neuroma.
Non Surgical Treatment
Most patients' symptoms subside when they change footwear to a wide soft shoe with a metatarsal support inside to relieve the pressure on the involved area. If this treatment fails, a cortisone injection into the nerve is occasionally helpful.
If these non-surgical measures do not work, surgery is sometimes needed. Surgery normally involves a small incision (cut) being made on either the top, or the sole, of the foot between the affected toes. Usually, the surgeon will then either create more space around the affected nerve (known as nerve decompression) or will cut out (resect) the affected nerve. If the nerve is resected, there will be some permanent numbness of the skin between the affected toes. This does not usually cause any problems. You will usually have to wear a special shoe for a short time after surgery until the wound has healed and normal footwear can be used again. Surgery is usually successful. However, as with any surgical operation, there is a risk of complications. For example, after this operation a small number of people can develop a wound infection. Another complication may be long-term thickening of the skin (callus formation) on the sole of the foot (known as plantar keratosis). This may require treatment by a specialist in care of the feet (chiropody).
It is not always possible to prevent a Morton's neuroma. However, you probably can reduce your risk by wearing comfortable shoes that have low heels, plenty of toe space and good arch support.