Overview
A Morton’s neuroma, or interdigital neuroma, is a painful condition which involves a nerve on the plantar aspect (bottom) of the foot. Occasionally a neuroma develops following a bruising injury to the sole of the foot, such as might be caused by jumping onto a rock or other objects, but in general, the origin of the condition is unknown.
Causes
Unfortunately, the cause of Morton?s Neuroma remains unknown to researchers. It is likely that a variety of factors may play a role in the development of this condition, including the presence of chronic pain conditions like fibromyalgia. Factors that may contribute to the development of Morton?s Neuroma include Wearing improperly fitting shoes can cause pressure on your foot, leading to swelling around the toe nerves. High heels are of particular concern as they cause a large amount of weight to be shifted to the ball of the foot. Repetitive activities like jogging, walking, and aerobics can also place a lot of pressure on the feet. This could lead to Morton?s Neuroma. Having a previous foot or muscle injury may cause you to hold your foot in a poor position when walking, contributing to nerve inflammation. Some people are just born with poorly shaped feet. People with extremely low arches or “flat feet” may suffer from Morton?s Neuroma more than others.
Symptoms
Often, no outward signs (such as a lump or unusual swelling) appear from the condition. Neuroma pain is most often described as a burning discomfort in the forefoot. Aching or sudden shooting pain in the forefoot is also common. All running sports, especially distance running can leave an athlete vulnerable to Morton?s Neuroma, which may appear or flare up in the middle of a run or at the end. The sufferer often has the desire to remove his shoe and rub the afflicted foot. Should the Neuroma be of sufficient size, or if footwear is particularly tight or uncomfortable, the painful condition may be present during normal walking. Numbness in the foot may precede or accompany Neuroma pain.
Diagnosis
To diagnose Morton’s neuroma the podiatrist commonly palpates the area to elicit pain, squeezing the toes from the side. Next he or she may try to feel the neuroma by pressing a thumb into the third interspace. The podiatrist then tries to elicit Mulder’s sign, by palpating the affected interspace with one hand and squeezing the entire foot at the same time with the other hand. In many cases of Morton’s neuroma, this causes an audible click, known as Mulder’s sign. An x-ray should be taken to ensure that there is not a fracture. X-rays also can be used to examine the joints and bone density, ruling out arthritis (particularly rheumatoid arthritis and osteoarthritis).
Non Surgical Treatment
Treatment for Morton?s neuroma will depend on how long you’ve had the condition and its severity. Simple non-surgical treatments are effective for some people. Others may need surgery. If Morton’s neuroma is diagnosed early, treatment will aim to reduce the pressure on the affected nerve. This is usually the nerve between the third and fourth toe bones (metatarsals). Your GP or podiatrist (foot specialist) may recommend changing the type of shoes you usually wear, shoes with a wider toe area may help ease the pressure on the nerve in your foot. Using orthotic devices, such as a support for the arch of your foot to help relieve the pressure on the nerve. Anti-inflammatory painkillers or a course of steroid injections into the affected area of your foot may help ease the pain and inflammation. Alcohol and local anaesthetic is injected into your foot using ultrasound for guidance, studies have shown that this type of treatment is effective. Resting your foot and massaging your toes may also help to relieve the pain. You can make an ice pack by freezing a small bottle of water and rolling it over the affected area.
Surgical Treatment
If pain persists with conservative care, surgery may be an appropriate option. The common digitial nerve is cut and the Mortons neuroma removed. This will result is numbness along the inside of the toes affected, and there is a small chance the end of the nerve will form a Stump Neuroma. Approximately 75% of people receive symptom resolution for Mortons Neuroma with conservative care.