Overview
A Morton’s neuroma, or interdigital neuroma, is a painful condition which involves a nerve on the plantar aspect (bottom) of the foot. Occasionally a neuroma develops following a bruising injury to the sole of the foot, such as might be caused by jumping onto a rock or other objects, but in general, the origin of the condition is unknown.
Causes
Morton’s Neuroma is a foot condition caused from an abnormal function of the foot that leads to bones squeezing a nerve usually between the 3rd and 4th metatarsal heads. Symptoms of Morton’s Neuroma often occur during or after you have been placing significant pressure on the forefoot area, while walking, standing, jumping, or sprinting. This condition can also be caused by footwear selection. Footwear with pointed toes and/or high heels can often lead to a neuroma. Constricting shoes can pinch the nerve between the toes, causing discomfort and extreme pain.
Symptoms
Symptoms include tingling in the space between the third and fourth toes, toe cramping, a sharp, shooting, or burning pain in the ball of the foot and sometimes toes, pain that increases when wearing shoes or pressing on the area, pain that gets worse over time. In rare cases, nerve pain occurs in the space between the second and third toes. This is not a common form of Morton neuroma, but treatment is similar.
Diagnosis
Diagnosis of Morton?s Neuroma typically involves a physical examination of the affected foot. Your health care provider will ask you about your symptoms and examine your feet and toes. He will manipulate your toes, pushing them from side to side and squeezing on the spaces in between. This physical exam will allow your health care provider to feel for any lumps that may be present under the soft tissue of your feet. Your health care provider may also listen for any clicking sounds that your bones may be making. Known as Muldor?s Sign, this clicking is common amongst sufferers of foot neuroma. Occasionally, an x-ray or MRI (magnetic resonance imaging) is performed to help rule out any breaks, sprains, or fractures in your foot.
Non Surgical Treatment
Initial therapies are nonsurgical and relatively simple. They can involve one or more of the following treatments. Changes in footwear. Avoid high heels or tight shoes, and wear wider shoes with lower heels and a soft sole. This enables the bones to spread out and may reduce pressure on the nerve, giving it time to heal. Orthoses. Custom shoe inserts and pads also help relieve irritation by lifting and separating the bones, reducing the pressure on the nerve. Injection. One or more injections of a corticosteroid medication can reduce the swelling and inflammation of the nerve, bringing some relief. Several studies have shown that a combination of roomier, more comfortable shoes, nonsteroidal anti-inflammatory medication, custom foot orthoses and cortisone injections provide relief in over 80 percent of people with Morton’s Neuroma.
Surgical Treatment
About one person in four will not require any surgery for Morton’s neuroma and their symptoms can be controlled with footwear modification and steroid/local anaesthetic injections. Of those who choose to have surgery, about three out of four will have good results with relief of their symptoms. Recurrent or persisting (chronic) symptoms can occur after surgery. Sometimes, decompression of the nerve may have been incomplete or the nerve may just remain ‘irritable’. In those who have had cutting out (resection) of the nerve (neurectomy), a recurrent or ‘stump’ neuroma may develop in any nerve tissue that was left behind. This can sometimes be more painful than the original condition.