Managing Mortons Neuroma

Overview

A morton's neuroma (or an "inter-digital" neuroma) is found between the toes of the foot, most commonly the third and fourth toes. It can also occur between the metatarsal bones (the long bones in the forefoot). It is basically an entrapped nerve, which becomes inflamed due to constant irritation from the surrounding bony structures.

Causes

The source of this pain is an enlargment of the sheath of an intermetatarsal nerve in the foot. This usually occurs in the third intermetatarsal space, the space between the third and fourth toes and metatarsals. It occurs here, at the site third intermetatarsal nerve, since this intermetatarsal nerve is the thickest being comprised of the joining of two different nerves. It also may occur in the other intermetatarsal areas, with the second interspace being the next most common location.

Symptoms

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.

Diagnosis

Negative signs include no obvious deformities, erythema, signs of inflammation, or limitation of movement. Direct pressure between the metatarsal heads will replicate the symptoms, as will compression of the forefoot between the finger and thumb so as to compress the transverse arch of the foot. This is referred to as Mulder?s Sign. There are other causes of pain in the forefoot. Too often all forefoot pain is categorized as neuroma. Other conditions to consider are capsulitis, which is an inflammation of ligaments that surrounds two bones, at the level of the joint. In this case, it would be the ligaments that attach the phalanx (bone of the toe) to the metatarsal bone. Inflammation from this condition will put pressure on an otherwise healthy nerve and give neuroma-type symptoms. Additionally, an intermetatarsal bursitis between the third and fourth metatarsal bones will also give neuroma-type symptoms because it too puts pressure on the nerve. Freiberg's disease, which is an osteochondritis of the metatarsal head, causes pain on weight bearing or compression.

Non Surgical Treatment

To help relieve the pain associated with Morton's neuroma and allow the nerve to heal, consider the following self-care tips. Take anti-inflammatory medications. Over-the-counter nonsteroidal anti-inflammatory medications, such as ibuprofen (Advil, Motrin IB, others) and naproxen (Aleve), can reduce swelling and relieve pain. Try ice massage. Regular ice massage may help reduce pain. Freeze a water-filled paper cup or plastic foam cup and roll the ice over the painful site. Change your footwear. Avoid high heels or tight shoes. Choose shoes with a broad toe box and extra depth. Take a break. For a few weeks, reduce activities such as jogging, aerobic exercise or dancing that subject your feet to high impact.

Surgical Treatment

Operative treatment of Morton?s neuroma should be entertained only after failure of nonoperative management. Standard operative treatment involves identifying the nerve and cutting (resecting) it proximal to the point where it is irritate/injured. This is usually done through an incision on the top (dorsal) aspect of the foot, although in rare instances, an incision on the sole (plantar) aspect of the foot maybe used. An incision on the sole of the foot works very well, unless an excessive scar forms in which case it can be problematic. Some physicians will attempt to treat Morton?s neuroma by releasing the intermetatarsal ligament and freeing the nerve of local scar tissue. This may also be beneficial.