Managing Mortons Neuroma

Overview

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.

Causes

Pronation of the foot can cause the metatarsal heads to rotate slightly and pinch the nerve running between the metatarsal heads. This chronic pinching can make the nerve sheath enlarge. As it enlarges it than becomes more squeezed and increasingly troublesome. Tight shoes, shoes with little room for the forefoot, pointy toeboxes can all make this problem more painful. Walking barefoot may also be painful, since the foot may be functioning in an over-pronated position.

Symptoms

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.

Diagnosis

During the exam, your doctor will press on your foot to feel for a mass or tender spot. There may also be a feeling of "clicking" between the bones of your foot. Some imaging tests are more useful than others in the diagnosis of Morton's neuroma. Your doctor is likely to order X-rays of your foot, to rule out other causes of your pain such as a stress fracture. Ultrasound. This technology uses sound waves to create real-time images of internal structures. Ultrasound is particularly good at revealing soft tissue abnormalities, such as neuromas. Magnetic resonance imaging (MRI). Using radio waves and a strong magnetic field, an MRI also is good at visualizing soft tissues. But it's an expensive test and often indicates neuromas in people who have no symptoms.

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 maybe 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 corticosteroid injections 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 from the nerve. 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 death of other important structures in the area.

Surgical Treatment

Surgery for neuroma most often involves removing affected nerve in the ball of the foot. An incision is made on the top of the foot and the nerve is carefully removed. Surgeon must remove the nerve far enough back so that the nerve doesn?t continue to become impinged at the ball of the foot. Alternatitvely, another type of surgery involves releasing a tight ligament that encases the nerve. Recovery after Morton?s neuroma (neurectomy) surgery is generally quick. Typically patients are walking on the operated foot in a post-surgical shoe for 2 - 4 weeks, depending on healing. Return to shoes is 2-6 weeks after the surgery. Factors that may prolong healing are age, smoking, poor nutritional status, and some medical problems.

Prevention

Although the exact causes of neuromas are not completely known, the following preventive steps may help. Make sure your exercise shoes have enough room in the front part of the shoe and that your toes are not excessively compressed. Wear shoes with adequate padding in the ball of the foot. Avoid prolonged time in shoes with a narrow toe box or excessive heel height (greater than two inches).