Overview
Morton?s neuroma is inflammation, thickening, or enlargement of the nerve between the bones of the toes (metatarsal bones). The condition is also called intermetatarsal neuroma. The thickening is usually found between bones of the third and fourth toes of the foot, but sometimes it may develop between the second and third toes. It occurs when the medial plantar nerve near the bones of those toes becomes compressed or irritated, possibly because the metatarsal bones press against the nerve in the narrow gap between the toes. If left untreated, Morton?s neuroma can cause a sharp, burning, or shooting pain that often gets worse over time. The pain becomes worse when a person walks or stands on the ball of the foot. Sometimes the pain reaches the toes next to the neuroma and a sensation of tingling or numbness is felt.
Causes
Occupational hazards. Individuals whose jobs place undue stress on their forefeet (with or without wearing improper footwear) are among those who complain of neuromas. Podiatric physicians report that individuals who work on ladders, or who perform activities on their knees (such as doing landscaping, carpeting, flooring, or other work on the ground) are at risk for this problem, too, since these activities cause stress to the nerve near the ball of the foot. Those who engage in high-impact activities that bring repetitive trauma to the foot (running, aerobics, etc.) have a better than average chance of developing a neuroma at the site of a previous injury. To put it more simply, if you have sustained a previous injury to your foot (a sprain, stress fracture, etc.), that area of your foot will be more prone to neuroma development than an area that has not been injured. However, sports injuries aren?t automatically a ticket to neuromas. Trauma caused by other forms of injury to the foot (dropping heavy objects, for example) can also cause a neuroma to develop at the site of the previous injury. Much though we hate to say it, sometimes neuromas just develop and nobody knows why. The patient doesn?t have a previous injury, is wearing properly fitted shoes, and doesn?t stress his/her feet with any specific activity but the neuroma develops anyway. It is important to remember that some of the factors listed above can work alone, or in combination with each other, to contribute to the formation of neuroma.
Symptoms
A Morton’s neuroma usually causes burning pain, numbness or tingling at the base of the third, fourth or second toes. Pain also can spread from the ball of the foot out to the tips of the toes. In some cases, there also is the sensation of a lump, a fold of sock or a “hot pebble” between the toes. Typically, the pain of a Morton’s neuroma is relieved temporarily by taking off your shoes, flexing your toes and rubbing your feet. Symptoms may be aggravated by standing for prolonged periods or by wearing high heels or shoes with a narrow toe box.
Diagnosis
Based on the physical examination, your doctor usually can diagnose a Morton’s neuroma without additional testing. A foot X-ray may be ordered to make sure that there isn’t a stress fracture, but it will not show the actual neuroma. If the diagnosis is in doubt, your doctor may request magnetic resonance imaging (MRI) of the foot.
Non Surgical Treatment
Anti-inflammatory drugs may be recommended to dull the pain and lessen swelling. Neuropathic pain medications such as the antionvulsants and / or antidepressants may be tried as well. Many are able to recover from this issue at home by icing the area, resting the feet, and by avoiding wearing narrow or tight shoes. If these remedies do not work to alleviate symptoms, the doctor may give special devices to separate the toes and avoid the squeezing of the nerve. Steroid injections may reduce pain and swelling. Surgery may be required if these do not help.
Surgical Treatment
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.
Yong Schrauger 