The nerves located on the bottom of the foot between the metatarsal heads (the bone of the toe closest to the foot) supply feeling, or sensation, to the toes. One of these nerves may become irritated by the ligament located above it, causing it to become thickened and painful. Generally this problem occurs most often between the third and fourth toes, but it can occur between the second and third toes as well. It is uncommon for a neuroma to be located between the first and second or fourth and fifth metatarsals. Rarely is there more than one neuroma in a foot.
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 primary symptoms include sharp, shooting pain, numbness or paresthesia in the forefoot and extending distally into the toes, typically in the region of the third and fourth toes. Symptoms are aggravated with narrow toe box shoes or those with high heels. There is usually a reduction of symptoms when walking barefoot or wearing shoes with an appropriately wide toe box. Symptoms are also aggravated with shoes that are tied too tight.
The exact cause of Mortons neuroma can often vary between patients. An accurate diagnosis must be carefully made by the podiatrist through thorough history taking and direct questioning to ensure all possible causes are addressed. The podiatrist will also gather further information about the cause through a hands on assessment where they will try to reproduce your symptoms. A biomechanical and gait analysis will also be performed to assess whether poor foot alignment and function has contributed to your neuroma.
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.
If other therapies have not worked it may be necessary to perform surgery. As surgery may result in permanent numbness in the affected toe, doctors ten to use this procedure as a last resort. However, in most cases surgery is extremely effective. The patient usually receives a local anesthetic. Surgery involves either removing the nerve, or removing the pressure on the nerve. Two surgical approaches are possible. The dorsal approach, the surgeon makes an incision on the top of the foot, allowing the patient to walk soon after surgery, because the stitches are not on the weight-bearing side of the foot. The plantar approach, the surgeon makes an incision on the sole of the foot. In most cases the patient will be in crutches for about three weeks. The resulting scar may make walking uncomfortable. However, with this approach the neuroma can be reached easily and resected without cutting any structures. There is a small risk of infection around the toes after surgery.