Overview
Mortons Neuroma is a common painful condition involving compression of nerves between the long bones of the forefoot just before they enter the toes. Commonly this involves the 3rd and 4th toes, however may affect the 2nd and 3rd toes. Repeated trauma or compression of these nerves causes the nerves to swell and thicken causing a Morton’s neuroma to develop.
Causes
Although the exact cause for this condition is unclear, a number of factors can contribute to the formation of a neuroma. Biomechanical deformities, such as a high-arched foot or a flat foot, can lead to the formation of a neuroma. These foot types bring on instability around the toe joints, leading to the development of the condition. Trauma can cause damage to the nerve, resulting in inflammation or swelling of the nerve. Improper footwear that causes the toes to be squeezed together is problematic. Avoid high-heeled shoes higher than two inches. Shoes at this height can increase pressure on the forefoot area. Repeated stress, common to many occupations, can create or aggravate a neuroma.
Symptoms
Feelings of numbness, tingling or tenderness in the ball of the foot (the area just behind the base of the toes) are some of the first signs of a condition known as Morton?s Neuroma. However, the condition is somewhat unpredictable, and symptoms may vary from patient to patient. Generally, however, the discomfort gets worse rather than better, and the patient may feel pain or a burning sensation that radiates out to the toes. Eventually, wearing shoes becomes uncomfortable (or even unbearable), and the patient may complain that the feeling is similar to that of having a stone bruise, or walking on a marble or pebble constantly, even though no there is no trauma to the skin, and no visible bump or lump on the sole of the foot.
Diagnosis
Metatarsal bones will be examined clinically, and often an x-ray will be taken to assess the particular case and ensure against other conditions, including fracture. When the foot is examined by a doctor, he may feel a characteristic ?click,? referred to as Mulder?s sign, and the interspaces between toe bones will often be tender. The doctor may put pressure on these areas to localize the site of pain and test for other conditions, including calluses or stress fractures. Range of motion tests will also be applied to rule out arthritis or joint inflammations. X-rays may be required to ensure there are no stress fractures or arthritis within the joints that join the toes to the foot. Tenderness in one or more metatarsal bones may imply a pre-stress fracture or stress-fracture. An ultrasound scan may be used to confirm diagnosis of Morton?s Neuroma, as x-ray will not detect the condition, (but can confirm that the bones are uninjured).
Non Surgical Treatment
In most cases, initial treatment for this condition consists of padding and taping to disperse weight away from the neuroma. If the patient has flatfeet, an arch support is incorporated into footwear. The patient is instructed to wear shoes with wide toe boxes and avoid shoes with high heels. An injection of local anesthetic to relieve pain and a corticosteroid to reduce inflammation may be administered. The patient is advised to return in a week or 2 to monitor progress. If the pain has been relieved, the neuroma is probably small and caused by the structure of the patient’s foot and the type of shoes the patient wears. It can be relieved by a custom-fitted orthotic that helps maintain the foot in a better position. Another type of therapy that may be used is alcohol sclerosing injections. In this treatment, the doctor injects a small amount of alcohol in the area of the neuroma area to help harden (sclerose) the nerve and relieve the pain. Injections are given every 7-10 days and, in many cases, 4-7 injections are needed for maximum relief. Please ask your physician for more information regarding this type of treatment.
Surgical Treatment
Interdigital neurectomy (removal of the diseased nerve) in right hands, should give satisfactory results almost all the time. Some of the reasons behind failure is when not enough nerve is dissected, mistakes in initial diagnosis, or bad handling of adjacent nerves, tendons and joint capsules during the operation. It is very common and acceptable to have some numbness in the area where the nerve used to be. This never causes any discomfort and often gets better in few years. It is crucial to address the biomechanical pathologies underlying the impingement of the nerve during and after the surgery.