A neuroma is a thickening of nerve tissue that may develop in various parts of the body. The most common neuroma in the foot is a Morton?s neuroma, which occurs between the third and fourth toes. It is sometimes referred to as an intermetatarsal neuroma. ?Intermetatarsal? describes its location in the ball of the foot between the metatarsal bones. Neuromas may also occur in other locations in the foot. MortonThe thickening, or enlargement, of the nerve that defines a neuroma is the result of compression and irritation of the nerve. This compression creates enlargement of the nerve, eventually leading to permanent nerve damage.
Causes
There are many reasons to develop a neuroma. Improper shoe gear is probably the most likely cause. Repetitive activity and excessive pressure on the ball of the foot are common. Heredity and genetic factors may also be involved. In many cases the structure of the foot may predispose the condition. Associated conditions that may cause neuroma include: bunion, hammer toes, ligament laxity, and/or a tight calf muscle. Some patients may have thinning of the fat pad on the ball of the foot, which may result in increased pressure of the nerves. Tight pointy shoes (and high heels) without padding may induce pain in the ball of the foot. Neuroma may occur suddenly, or develop over time.
Symptoms
There may be pain at the end of the push-off phase when walking or running, and this pain is generally worse when the client is wearing shoes as opposed to being barefoot. Clients may also report a relief of symptoms by massaging the foot, which may spread the metatarsal heads and mobilize the entrapped nerve.
Diagnosis
The doctor will ask about your symptoms and medical history. A physical exam will be done. Initial diagnosis of Morton's neuroma is based on your description of the type and location of pain and discomfort in the foot. The diagnosis will be confirmed by a physical exam of the foot, including checking for mechanical abnormalities in the foot, squeezing the side of the foot, which will usually cause pain when Morton's neuroma is present. Examination of your shoes to check for excess wear in parts of the shoe, check to see whether the shoes are too tight. Imaging tests evaluate the foot and surrounding structures. This may be done with X-ray, MRI scan, Ultrasound. Injections of local anesthetic can also be used for diagnosis.
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
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.