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.
The pain of Morton's neuroma occurs when the nerve connecting the toe bones (metatarsal bones) becomes irritated or compressed. The exact cause of the irritation is unknown, but it may be the metatarsal bones pressing against the nerve when the gap between the bones is narrow. This causes the nerve and surrounding tissue to thicken. Some experts believe that a number of other foot problems, including flat feet, high foot arches, bunions and hammer toes, may also play a role in Morton's neuroma.
Symptoms typically include pain, often with pins and needles on one side of a toe and the adjacent side of the next toe. Pain is made worse by forefoot weight bearing and can also be reproduced by squeezing the forefoot to further compress the nerve. Pressing in between the third and forth metatarsals for example with a pen can also trigger symptoms.
Morton?s neuroma can be identified during a physical exam, after pressing on the bottom of the foot. This maneuver usually reproduces the patient?s pain. MRI and ultrasound are imaging studiesthat can demonstrate the presence of the neuroma. An x-ray may also be ordered to make sure no other issues exist in the foot. A local anesthetic injection along the neuroma may temporarily abolish the pain, and help confirm the diagnosis.
Non Surgical Treatment
Common treatments involve wearing different shoes or using arch supports. Resting the foot, massaging the toes and using an ice pack may work for some people. A GP or a podiatrist (foot specialist) may also recommend anti-inflammatory painkillers or a course of steroid injections. Numbing injections, in which alcohol and a local anaesthetic are injected into the affected area of the foot, may also be effective. In extreme cases, when the condition does not respond to treatment, day case surgery may be needed.
If your pain continues despite several months of conservative treatment, your doctor may recommend surgery to remove the neuroma or to widen the space through which the affected nerve travels. These types of surgery often are done under local anesthesia. If your doctor removes a portion of the affected nerve along with the neuroma, you may develop permanent numbness between the toes.