What Causes Mortons Neuroma

Overview

Patients with Morton?s neuroma present with pain in the forefoot, particularly in the ?ball? of the foot. However, not all pain in the forefoot is a Morton?s neuroma. In fact, most chronic pain in the forefoot is NOT the result of a Morton?s neuroma, but rather is from metatarsalgia – inflammation (synovitis) of the ?toe/foot? joints. The symptoms from Morton?s neuroma are due to irritation to the small digital nerves, as they pass across the sole of the foot and into the toes. Therefore, with a true Morton?s neuroma, it is not uncommon to have nerve-type symptoms, which can include numbness or a burning sensation extending into the toes. There are several interdigital nerves in the forefoot. The most common nerve to develop into a neuroma is between the 3rd and 4th toes. With a true neuroma, the pain should be isolated to just one or two toes.

Causes

A Morton’s neuroma commonly occurs due to repetitive weight bearing activity (such as walking or running) particularly when combined with tight fitting shoes or excessive pronation of the feet (i.e. “flat-feet”). The condition is also more common in patients with an unstable forefoot allowing excessive movement between the metatarsal bones. A Morton’s neuroma can also occur due to certain foot deformities, trauma to the foot, or the presence of a ganglion or inflamed bursa in the region which may place compressive forces on the nerve.

Symptoms

You may initially experience a tingling sensation in the space between your toes, which gets worse over time. This leads to cramp in your toes and a sharp shooting or burning pain on the ball of your foot or at the base of your toes. The pain is often worse when walking or wearing shoes that press on the affected area. This is caused by irritation of the nerve between your toe bones (metatarsal bones). The tingling will eventually lead to pain, which can get worse over time. You may also experience cramping of your toes. The pain is usually felt as a sharp shooting or burning pain on the ball of the foot or at the base of the toes, which is often made worse when you’re walking. Some people with Morton’s neuroma feel anxious about walking or even placing their foot on the ground. The pain is likely to be more intense if you wear tight shoes, so wearing shoes that have more room in the toe area can help. Rubbing your foot may also lessen the pain.

Diagnosis

During the examination, your physician will feel for a palpable mass or a “click” between the bones. He or she will put pressure on the spaces between the toe bones to try to replicate the pain and look for calluses or evidence of stress fractures in the bones that might be the cause of the pain. Range of motion tests will rule out arthritis or joint inflammations. X-rays may be required to rule out a stress fracture or arthritis of the joints that join the toes to the foot.

Non Surgical Treatment

Anti-inflammatory drugs may be recommended to dull the pain and lessen swelling. Neuropathic pain medications such as the antionvulsants and / or antidepressants may be tried as well. Many are able to recover from this issue at home by icing the area, resting the feet, and by avoiding wearing narrow or tight shoes. If these remedies do not work to alleviate symptoms, the doctor may give special devices to separate the toes and avoid the squeezing of the nerve. Steroid injections may reduce pain and swelling. Surgery may be required if these do not help.

Surgical Treatment

When early treatments fail and the neuroma progresses past the threshold for such options, podiatric surgery may become necessary. The procedure, which removes the inflamed and enlarged nerve, can usually be conducted on an outpatient basis, with a recovery time that is often just a few weeks. Your podiatric physician will thoroughly describe the surgical procedures to be used and the results you can expect. Any pain following surgery is easily managed with medications prescribed by your podiatrist.