Morton?s neuroma is inflammation, thickening, or enlargement of the nerve between the bones of the toes (metatarsal bones). The condition is also called intermetatarsal neuroma. The thickening is usually found between bones of the third and fourth toes of the foot, but sometimes it may develop between the second and third toes. It occurs when the medial plantar nerve near the bones of those toes becomes compressed or irritated, possibly because the metatarsal bones press against the nerve in the narrow gap between the toes. If left untreated, Morton?s neuroma can cause a sharp, burning, or shooting pain that often gets worse over time. The pain becomes worse when a person walks or stands on the ball of the foot. Sometimes the pain reaches the toes next to the neuroma and a sensation of tingling or numbness is felt.
Morton's neuroma is an inflammation caused by a buildup of fibrous tissue on the outer coating of nerves. This fibrous buildup is a reaction to the irritation resulting from nearby bones and ligaments rubbing against the nerves. Irritation can be caused by wearing shoes that are too tight, wearing shoes that place the foot in an awkward position, such as high heels, a foot that is mechanically unstable, repetitive trauma to the foot such as from sports activities like tennis, basketball, and running. Trauma to the foot caused by an injury such as a sprain or fracture. It is unusual for more than one Morton's neuroma to occur on one foot at the same time. It is rare for Morton's neuroma to occur on both feet at the same time.
The symptoms of a Morton's neuroma are classic in nature. The patient complains of a burning , tingling, slightly numb feeling (dysesthesias) which radiates out to the toes on either side of the interspace that is involved. For instance, a Morton's neuroma of the third interspace will result in pain between the third and fourth toes, and a neuroma in the second interspace will cause pain between the second and third toes. The symptoms are usually aggravated by wearing shoes, particularly those with high heels. Symptoms are relieved by walking in flat, wide shoes or going barefoot. Rarely will the patient experience pain when sitting or laying down.
X-rays of your affected foot will not show a neuroma, as neuromas are made up of soft tissue. X-rays may be helpful, however, in helping rule in osteoarthritis or a stress fracture as the cause of your symptoms. Ultrasonography and MRI are sometimes used to help diagnose neuromas, although they are often ineffective. The clinical diagnosis by a foot care expert with experience treating this health problem is usually the most effective way to diagnose neuromas. Your podiatrist will attempt to duplicate your neuroma symptoms by pressing on the involved nerve at various points, and he or she may try to cause a clicking of your nerve that indicates nerve enlargement.
Non Surgical Treatment
Most non-operative treatment is usually successful, although it can take a while to figure out what combination of non-operative treatment works best for each individual patient. Non-operative treatment may include the use of comfort shoe wear. The use of a metatarsal pad to decrease the load through the involved area of the plantar forefoot. A period of activity modification to decrease or eliminate activities, which may be exacerbating the patient?s symptoms. For example, avoiding long periods of standing or other activities that result in significant repetitive loading to the forefoot can be very helpful. Wearing high heels should be avoided. Local can help decrease inflammation associated with the nerve. However, this does not necessarily address the underlying loading forces that maybe causing the injury to the nerve in the first place. It has been proposed that an alcohol injection in and around the nerve will cause a controlled death to the nerve and subsequently eliminate symptoms. In theory, this may be helpful. In practice, adequate prospective studies have not demonstrated the benefit of this procedure above and beyond the other standard, non-operative treatments available. In addition there is the concern that the alcohol will cause excessive scarring and damage to other important structures in the area.
The ultimate success of a Morton?s neuroma treated surgically can be variable. In cases where the underlying problem is only an irritated nerve (a true Morton?s neuroma), then surgery will probably be curative (although it may take a few months for the foot to fully heal). But in many cases, forefoot pain is more complex. There may be an irritated nerve or two causing pain, but the real problem is often excessive loading of the lesser metatarsals. The generic term for this condition is metatarsalgia. When considering surgery, identifying and addressing these problems may lead to a better end result.
Wearing shoes that fit properly and that have plenty of room in the toe area may help prevent Morton's neuroma.