Put simply - Morton's neuroma is a swollen (inflamed) nerve in the ball of the foot, commonly between the base of the second and third toes. Patients experience numbness and pain in the affected area, which is relieved by removing footwear and/or massaging the foot. A neuroma is a tumor that arises in nerve cells, a benign growth of nerve tissue that can develop in various parts of the body. In Morton's neuroma the tissue around one of the nerves leading to the toes thickens, causing a sharp, burning pain in the ball of the foot. A sharp severe pain, often described as a red hot needle may come on suddenly while walking. There may also be numbness, burning and stinging in the toes. Although it is labeled a neuroma, many say it is not a true tumor, but rather a perineural fibroma (fibrous tissue formation around nerve tissue).
The exact cause of Morton's neuroma is not known. However, it is thought to develop as a result of long-standing (chronic) stress and irritation of a plantar digital nerve. There are a number of things that are thought to contribute to this. Some thickening (fibrosis) and swelling may then develop around a part of the nerve. This can look like a neuroma and can lead to compression of the nerve. Sometimes, other problems can contribute to the compression of the nerve. These include the growth of a fatty lump (called a lipoma) and also the formation of a fluid-filled sac that can form around a joint (a bursa). Also, inflammation in the joints in the foot next to one of the digital nerves can sometimes cause irritation of the nerve and lead to the symptoms of Morton's neuroma.
Symptoms include tingling in the space between the third and fourth toes, toe cramping, a sharp, shooting, or burning pain in the ball of the foot and sometimes toes, pain that increases when wearing shoes or pressing on the area, pain that gets worse over time. In rare cases, nerve pain occurs in the space between the second and third toes. This is not a common form of Morton neuroma, but treatment is similar.
The physician will make the diagnosis of Morton's neuroma based upon the patient's symptoms as described above in an interview, or history, and a physical examination. The physical examination will reveal exceptional tenderness in the involved interspace when the nerve area is pressed on the bottom of the foot. As the interspace is palpated, and pressure is applied from the top to the bottom of the foot, a click can sometimes be felt which reproduces the patient's pain. This is known as a Mulder's sign. Because of inconsistent results, imaging studies such as MRI or ultrasound scanning are not useful diagnostic tools for Morton's neuroma. Thus the physician must rely exclusively on the patient's history and physical examination in order to make a diagnosis.
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.
When medications or other treatments do not work, podiatric surgery may be required. The most common surgical procedure for treating Morton?s neuroma is a neurectomy, in which part of the nerve tissue is removed. Although this procedure effectively removes the original neuroma, sometimes scar tissue known as a stump neuroma forms at the site of the incision. This may result in tingling, numbness, or pain following surgery. Surgery is effective in relieving or reducing symptoms for Morton?s neuroma patients in about 75% to 85% of all cases. Occasionally, minimally invasive radio frequency ablation is also used to treat Morton's neuroma.