Morton's neuroma is a painful condition in which excess fibrous tissue accumulates around a nerve in the ball the foot, usually between the third and fourth toes. Patients may experience pain, burning, tingling or numbness in the foot, radiating into the toes, and often report feeling as if they are walking on a pebble. Pain may be soothed by taking weight off the foot or by massaging the area. The pain of Morton's neuroma is likely to worsen over time, becoming more severe and more persistent. The condition is found more frequently in women than in men.
Risk Factors for Morton's Neuroma
The specific cause of a Morton's neuroma is unknown, but the condition begins a nerve in the forefoot is compressed by the long bones called the metatarsals. This occurs when these bones move abnormally or when there is a traumatic injury to the area.
Risk factors for a Morton's neuroma include:
- Flat feet or high arches
- Bunions, hammertoes, or other foot deformities
- Ill-fitting or high-heeled shoes
- Repetitive trauma caused by running or other sports
- Injury resulting from previous surgery
Diagnosis of Morton's Neuroma
Morton's neuroma is normally diagnosed by a physical examination, an MRI and a high-resolution ultrasound. X-rays or electromyography (EMG) may be administered to rule out other conditions that cause similar symptoms, such as arthritis, stress fractures, tendon inflammation or neuromuscular disorders.
Treatment of Morton's Neuroma
Home remedies for Morton's neuroma include resting the foot, applying ice packs and massaging the area to relax the foot muscles. Taking anti-inflammatory medications, wearing roomier shoes, and padding or taping the area may also be helpful. Medical interventions include nerve-blocking medications and corticosteroid injections to reduce inflammation. Physical therapy and custom-made orthotics can help to correct abnormal metatarsal movement.
If none of these more conservative treatments relieves the symptoms, a surgical procedure may be required. One minimally invasive procedure sometimes used is cryogenic neuroablation. Exposing the nerve to freezing temperatures can disrupt the transmission of pain signals from the nerve, but it is a temporary solution. Another option is decompression surgery, in which the structure pinching the nerve, often a ligament, is removed.
In some cases, relief will only be provided by a procedure to remove the thickened nerve tissue itself. If the nerve is permanently damaged, it can be removed, either through chemical destruction or surgical excision. While most operations for Morton's neuroma are successful, a small percentage of patients continue to experience pain even after surgery.