Morton neuromas are focal areas of symptomatic perineural fibrosis around a plantar digital nerve of the foot. The abnormality is non-neoplastic and does not represent a true neuroma. It may more correctly be known as Morton?s metatarsalgia. The condition is thought to be due to chronic entrapment of the nerve by the intermetatarsal ligament. It most often occurs in middle-aged individuals and is many times more common in women than men. Approximately 30% of asymptomatic middle-aged persons have the radiological pathologic findings of a Morton?s neuroma.
Morton's neuroma develops for several reasons. The primary reason is wearing narrow toe-box shoes, which compress the metatarsal heads. Certain anatomical factors also make nerve compression more likely with the narrow toe box shoes. In some people fibers, the medial and lateral plantar nerves converge close to the heads of the third and fourth metatarsals. This junction creates a larger nerve structure between the metatarsal heads making it more vulnerable to compression.
What are the symptoms of Morton?s neuroma? A sharp or stinging pain between the toes when standing or walking. Pain in the forefoot between the toes. Swelling between the toes. Tingling (?pins and needles?) and numbness. Feeling like there is a ?bunched up sock? or a pebble or marble under the ball of the foot.
There is a special orthopedic test called the Morton's test that is often used to evaluate the likelihood of plantar nerve compression. For this test, the client is supine on the treatment table. The practitioner grasps the client's forefoot from both sides and applies moderate pressure, squeezing the metatarsal heads together. If this action reproduces the client's symptoms (primarily sharp, shooting pain into the toes, especially the third and fourth), Morton's neuroma may exist.
Non Surgical Treatment
Orthotics and corticosteroid injections are widely used conservative treatments for Morton?s neuroma. In addition to traditional orthotic arch supports, a small foam or fabric pad may be positioned under the space between the two affected metatarsals, immediately behind the bone ends. This pad helps to splay the metatarsal bones and create more space for the nerve so as to relieve pressure and irritation. It may however also elicit mild uncomfortable sensations of its own, such as the feeling of having an awkward object under one's foot. Corticosteroid injections can relieve inflammation in some patients and help to end the symptoms. For some patients, however, the inflammation and pain recur after some weeks or months, and corticosteroids can only be used a limited number of times because they cause progressive degeneration of ligamentous and tendinous tissues.
If your pain continues despite several months of conservative treatment, your doctor may recommend surgery to remove the neuroma or to widen the space through which the affected nerve travels. These types of surgery often are done under local anesthesia. If your doctor removes a portion of the affected nerve along with the neuroma, you may develop permanent numbness between the toes.