FOOT PAIN & PODIATRY ONLINE FOOT PAIN - NEUROMA (MORTON'S TYPE) When foot pain and tenderness occurs under the ball of the foot, usually the podiatry presentation is either a metatarsal stress fracture, a nerve is being entrapped or a painful callous is present. A callous is usually the cause of the ball of the foot pain if the bone does not hurt with compression from top and bottom but the skin is tender.  A nerve problem is present if the pain is between the metarsal bones in he ball of the foot and the skin and metatarsal heads do not hurt with squeezing the bones.  Review the Corn and Callous Page or the Metatarsal Stress Fracture Page if you think your problem is a painful callous or a stress fracture and not a neuroma. A Morton's Neuroma is a name given to a scared and enlarged nerve that is between the two lessor metatarsal heads.  The most common place for a neuroma to occur is between the third and forth metatarsal heads.  The third and forth metatarsal heads connect to different bones in the middle of the foot and with twisting of the forefoot during gait, these two bones rotate in separate directions causing the nerve to become pinched.  A neuroma is a condition that occurs from repetitive injury to the nerve that is running under and between the metatarsal heads in that the nerve enlarges with scar tissue.  The primary cause of the nerve injury is from a twisting of the forefoot while walking that is associated with flattening of the foot or pronation.  The nerve innervates the inside bottom area of the two toes that the nerve passes between.  With injury to the nerve, the typical pain that is experienced is an electrical burning pain that may leave the toes numb intermittently.  Usually the pain is not subtle but very obvious and occurs on and off during weight bearing.  The pain can also continue into the night even after the foot is rested.  The clinical examination is classic for radiating pain when the nerve is pushed on from below and between the metarsal heads.  Sometimes there is even a click that occurs or a marble feeling to the bottom of the foot with walking as the nerve becomes enlarged with repeated injury.  With each injury to the nerve the nerve enlarges with scar tissue that is a mixture of scar and nerve tissue.  It is the repeated scarring that is the cause of the pain as the nerve tissue has no where go when you are standing on your foot and the metatarsal bones are above and around the nerve. Treatment with a new nerve injury is aimed at changing the way in which you stand by changing shoes to more support motion control athletic shoe and many times custom molded foot orthotics.  Cortisone injection therapy is used to try to reduce the amount of inflammation in the nerve and to relieve pain.  Without any other intervention, the cortisone shots have little long term use for curing the neuroma condition.  If treatment is quickly administered that includes antiinflammatory medications such as Celebrex, the prognosis is excellent for resolving the nerve injury condition.  If the nerve injury has progressed too far with repeated compression injuries, the nerve will increase in size from a normal diameter of a 1/16th of an inch to over a half inch from the scar formation.  In half the cases, where a patient has a neuroma, half resolve the problem without surgery and half go on to surgery.  Surgery entails either repositioning the nerve or removing the scarred nerve and placing the cut nerve end into a small muscle next to the metatarsal.  If the nerve is not implanted into the interossious muscle adjacent to the shaft of the metatarsal, there is a 60% re-occurrence rate of having the neuroma return.  Extremity nerves that go to the skin will regenerate unless the nerve end is placed into a tissue that already has a nerve innervation such as a muscle belly.  For this reason, patients who have had neuroma surgery and not had the nerve implanted into muscle should expect a re-occurrence after surgery.  Although rare, if the nerve is implanted into muscle, the nerve can still develop a painful mushroom at the end of the nerve where the nerve was cut and implanted into muscle.  The recovery from neuroma surgery is usually minimally painful if tissues are respected and the surgeon closes the tissues in layers and lets down the tourniquet prior to closing the skin and not after the skin is closed.  The patient should not need to take more that a few pain pills in the first couple days and use antiinflammatory medications for the next two weeks to control the amount of swelling in the area.   Ultimately, early treatment of neuromas is important in preventing the progressing of the scaring of the nerve. Surgery should be reserved for those patients who have not responded to changing shoe gear, foot orthotics, cortisone injection therapy, rest and anti-inflammatory medications.  In a good doctor's hands, if surgery is needed, neuroma surgery should go smooth with a rare change that the neuroma will return. Copyright © 1999 PLACENTIA-LINDA FOOT AND ANKLE GROUP Podiatry Associates. All rights reserved.