If you sometimes feel that you are “walking on a marble,” and you have persistent pain in the ball of your foot, you may have a condition called Morton’s neuroma. A neuroma is a benign tumor of a nerve. Morton’s neuroma is not actually a tumor, but a thickening of the tissue that surrounds the digital nerve leading to the toes. Morton’s neuroma occurs as the nerve passes under the ligament connecting the toe bones (metatarsals) in the forefoot. Morton’s neuroma most frequently develops between the third and fourth toes, usually in response to irritation, trauma or excessive pressure. The incidence of Morton’s neuroma is 8 to 10 times greater in women than in men.
The source of this pain is an enlargment of the sheath of an intermetatarsal nerve in the foot. This usually occurs in the third intermetatarsal space, the space between the third and fourth toes and metatarsals. It occurs here, at the site third intermetatarsal nerve, since this intermetatarsal nerve is the thickest being comprised of the joining of two different nerves. It also may occur in the other intermetatarsal areas, with the second interspace being the next most common location.
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
If you have Morton’s neuroma, shoes with a wider toe area may be recommended. You can also take painkillers to help ease the pain. Steroid injections may also be given to treat the affected nerve. If these treatments don’t work, surgery may be needed. This involves removing the thickened tissue around the nerve (and sometimes the nerve itself) to release the pressure.
Operative treatment of Morton?s neuroma should be entertained only after failure of nonoperative management. Standard operative treatment involves identifying the nerve and cutting (resecting) it proximal to the point where it is irritate/injured. This is usually done through an incision on the top (dorsal) aspect of the foot, although in rare instances, an incision on the sole (plantar) aspect of the foot maybe used. An incision on the sole of the foot works very well, unless an excessive scar forms in which case it can be problematic. Some physicians will attempt to treat Morton?s neuroma by releasing the intermetatarsal ligament and freeing the nerve of local scar tissue. This may also be beneficial.
Wearing shoes that fit properly and that have plenty of room in the toe area may help prevent Morton’s neuroma.