Morton's neuroma is an inflammation of the nerves in the foot that go to the toes. Although the name includes the word ?neuroma,? it is not really a tumor. It can affect any of the toes in the foot. However, it most often affects the nerves that run between the third and fourth, or second and third toes.
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.
Normally, there are no outward signs, such as a lump, because this is not really a tumor. Burning pain in the ball of the foot that may radiate into the toes. The pain generally intensifies with activity or wearing shoes. Night pain is rare. There may also be numbness in the toes, or an unpleasant feeling in the toes. Runners may feel pain as they push off from the starting block. High-heeled shoes, which put the foot in a similar position to the push-off, can also aggravate the condition. Tight, narrow shoes also aggravate this condition by compressing the toe bones and pinching the nerve.
The clinical symptoms should quickly lead your doctor to suspect a neuroma. When examined, the doctor may feel a "click" which is known as Mulder's sign. There may be tenderness in the interspace. The metatarsal bones will also be examined both clinically (and often with an xray). Tenderness at one of the metatarsal bones can suggest an overstress reaction (pre-stress fracture or stress fracture) in the bone. An ultrasound scan can confirm the diagnosis and is a less expensive and at this time, at least as sensitive a test as an MRI. An x-ray does not show neuromas, but can be useful to "rule out" other causes of the pain.
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.
Recently, an increasing number of procedures are being performed at specialist centers under radiological or ultrasound guidance. Recent studies have shown excellent results for the treatment of Morton's neuroma with ultrasound guided steroid injections, ultrasound guided sclerosing alcohol injections, ultrasound guided radiofrequency ablation and ultrasound guided cryo-ablation.
Women, particularly those who wear tight shoes, are at greatest risk for Morton?s neuroma. The best way to prevent the condition is to wear shoes with wide toe boxes. Tight, pointed shoes squeeze bones, ligaments, muscles and nerves. High heels may worsen the problem by shifting your weight forward. Over time, this combination can cause the nerves to swell and become painful.