Morton’s neuroma is named after Dr Morton who first described this condition in 1876. It is sometimes called Morton’s metatarsalgia or interdigital neuroma. It is a condition that affects one of the common plantar digital nerves that run between the long bones (metatarsals) in the foot. It most commonly affects the nerve between the third and fourth metatarsal bones, causing pain and numbness in the third and fourth toes. It can also affect the nerve between the second and third metatarsal bones, causing symptoms in the second and third toes. Morton’s neuroma rarely affects the nerve between the first and second, or between the fourth and fifth, metatarsal bones. It tends to affect only one foot. It is rare to get two neuromas at the same time in the same foot.
Pronation of the foot can cause the metatarsal heads to rotate slightly and pinch the nerve running between the metatarsal heads. This chronic pinching can make the nerve sheath enlarge. As it enlarges it than becomes more squeezed and increasingly troublesome. Tight shoes, shoes with little room for the forefoot, pointy toeboxes can all make this problem more painful. Walking barefoot may also be painful, since the foot may be functioning in an over-pronated position.
While the condition may at first only appear during heavy repetitive stress or when wearing particular shoes which aggravate the foot, the Neuroma can become increasingly inflamed and produce more constant discomfort, lasting days or weeks. Runners may experience pain pushing off from starting blocks. Tight or narrow shoes as well as high heels likewise aggravate the Neuroma. A checklist of symptoms includes burning pain, occasionally numbness in the ball of the foot. Radiating pain from the ball of the foot to the toes. Intensifying pain during activity and when wearing shoes. Occasional numbness, discomfort, tingling or ?electrical shock sensation? in the toes. Pain between the third and fourth toes, often occurring from the outer side of one toe to the inner side of the adjoining toe. Pain upon leaving the starting blocks in running sports.
During the examination, your physician will feel for a palpable mass or a “click” between the bones. He or she will put pressure on the spaces between the toe bones to try to replicate the pain and look for calluses or evidence of stress fractures in the bones that might be the cause of the pain. Range of motion tests will rule out arthritis or joint inflammations. X-rays may be required to rule out a stress fracture or arthritis of the joints that join the toes to the foot.
Non Surgical Treatment
Pain is the main reason that you seek treatment for a neuroma. Analgesics may help. Inflammation it best eased via ice therapy and techniques or exercises that deload the inflammed structures. Anti-inflammatory medications may help. Your physiotherapist will use an array of treatment tools to reduce your pain and inflammation. These include: ice, electrotherapy, acupuncture, deloading taping techniques, soft tissue massage and orthotics to offload the irritated nerve. One of the biggest factors in relieving pain may be changing or modifying your footwear. This may mean adding felt, foam or gel products to your shoe to help offload the area, or looking at avoiding tight fitting heels or shoes.
If these non-surgical measures do not work, surgery is sometimes needed. Surgery normally involves a small incision (cut) being made on either the top, or the sole, of the foot between the affected toes. Usually, the surgeon will then either create more space around the affected nerve (known as nerve decompression) or will cut out (resect) the affected nerve. If the nerve is resected, there will be some permanent numbness of the skin between the affected toes. This does not usually cause any problems. You will usually have to wear a special shoe for a short time after surgery until the wound has healed and normal footwear can be used again. Surgery is usually successful. However, as with any surgical operation, there is a risk of complications. For example, after this operation a small number of people can develop a wound infection. Another complication may be long-term thickening of the skin (callus formation) on the sole of the foot (known as plantar keratosis). This may require treatment by a specialist in care of the feet (chiropody).