Nerve Conditions Alcoholic Neuropathy

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1 Nerve Conditions Alcoholic Neuropathy Peripheral Neuropathy is a nerve condition that affects the arms, hands, legs, and feet. The most common form of peripheral neuropathy is due to diabetes. Diabetic Peripheral Neuropathy People with diabetes have an abnormal elevation of their blood sugar, and lack adequate insulin to metabolize the blood sugar. As a consequence, the blood glucose (sugar) abnormally enters certain nerve tissue and damages the nerve. This can occur in any type of diabetes. It does not matter if the patient is on insulin, is taking pills, or is diet controlled. The nerve damage that occurs is considered to be permanent. As the nerve damage occurs, the protective sensations are affected. These include a person's ability to determine the difference between sharp and dull, hot and cold, pressure differences, and vibration. These senses become dulled and/or altered. The process begins as a burning sensation in the toes and progresses up the foot in a "stocking distribution". As the condition progresses, the feet become more and more numb. Some people will feel as though a pair of socks on their feet, when in fact they do not. Other patients will describe the feeling of walking on cotton, or a water-filled cushion. Some patients complain of their feet burn at night, making it difficult to sleep. The feet may also feel like they are cold, however, to the touch, they have normal skin temperature. Diabetic peripheral neuropathy is not reversible. The progression of the condition can be slowed or halted by maintaining normal blood glucose levels. As the patient develops diabetic neuropathy, they have a greater risk of developing skin ulcerations and infections. Areas of corns and calluses on the feet represent areas of excessive friction or pressure. These areas, if not properly cared for by a foot specialist, will often break down and cause ulcerations. Ulcerations and infection can form under the callused area. These callused areas may not be painful. As a result, they can progress to ulceration without being noticed. Ingrown toenails can progress to severe infections in people with neuropathy. Simple things like trimming the toenails present a risk to these patients because they may accidentally cut the skin and not feel it. People with neuropathy must be very cautious and inspect their feet daily. They should not soak their feet in hot water or use heating pads to warm their feet. This can result in accidental burns to the skin. Barefoot walking should be avoided because of the risk of stepping on something sharp and not being aware of it. The inside of the shoes should be inspected before putting the shoes on to insure that no foreign object is inside the shoe (see Do's and Don'ts-Diabetic Foot Care Tips). Alcoholic Peripheral Neuropathy Alcoholic neuropathy is caused by the prolonged use of alcoholic beverages. Ethanol, the alcoholic component of these beverages, is toxic to nerve tissue. Over time, the nerves in the feet and hands can become damaged resulting in the same loss of sensation as that seen in diabetic

2 neuropathy. The damage to these nerves is permanent. A person with this condition is at the same risk, and should take the same precautions as people with diabetic peripheral neuropathy. Peripheral neuropathy can also be caused by exposure to toxins such as pesticides and heavy metals. Treatment For Peripheral Neuropathy Treatment for peripheral neuropathy is, for the most part, directed at the symptoms of the condition. Vitamin B12 injections may be helpful if the patient has a vitamin B deficiency. There are certain oral medications that may ease the burning pain that can be prescribed by your doctor. Topical ointments should only be used with the advice of your doctor. Magnetic therapy and Galvanic Stimulation are alternative forms of treatment but results are varied and difficult to quantify. Chemical Neurolysis for the Treatment of Neuromas The chemical destruction of the nerve, called neurolysis, is an older form of treatment that has recently come back into vogue. This treatment requires a series of injections of ethanol mixed with a local anesthetic. The injections are given into the area of the neuroma. Nerve tissue has a natural affinity for ethanol, and it is readily absorbed into the nerve. Ethanol, however, is toxic to nerve tissue and with repeated exposure, will destroy the nerve. The rate of success is variable, but has been reported to be over 60%. Many insurance plans will not pay for weekly injections and require the doctor to wait a minimum of ten days between injections before they will reimburse for the procedure. This likely reduces the rate of success for this treatment, because during the time between the injections, the nerve will attempt to repair itself. One way to solve this delay is for the patient to pay for those injections not paid for by the insurance plan. The disadvantages for this form of treatment are the need for repeated visits to the doctor s office, and the occasional pain in the area of the injection the following day or two after it has been administered. The advantages to this form of treatment is that it requires a minimal amount of time off of work and the overall cost as compared to the surgical removal of the nerve. If this form of treatment fails, then surgical removal is the only option that remains. Neuroma A neuroma is the swelling of nerve that is a result of a compression or trauma. They are often described as nerve tumors. However, they are not in the purest sense a tumor. They are a swelling within the nerve that may result in permanent nerve damage. The most common site for a neuroma is on the ball of the foot. The most common cause of neuroma in ball of the foot is the abnormal movement of the long bones behind the toes called metatarsal bones. A small nerve passes between the spaces of the metatarsals. At the base of the toes, the nerves split forming a "Y" and enter the toes. It is in this area the nerve gets pinched and swells, forming the neuroma. Burning pain, tingling, and numbness in one or two of the toes is a common symptom. Sometimes this pain can become so severe, it can bring tears to a patient's eyes. Removing the

3 shoe and rubbing the ball of the foot helps to ease the pain. As the nerve swells, it can be felt as a popping sensation when walking. Pain is intermittent and is aggravated by anything that results in further pinching of the nerve. When the neuroma is present in the space between the third and fourth toes, it is called a Morton's Neuroma. This is the most common area for a neuroma to form. Another common area is between the second and third toes. Neuromas can occur in one or both of these areas and in one or both feet at the same time. Neuromas are very rare in the spaces between the big toe and second toe, and between the fourth and fifth toes. Neuromas have been identified in the heel area, resulting in heel pain. A puncture wound or laceration that injures a nerve can cause a neuroma. These are called traumatic Neuromas. Neuromas can also result following a surgery that may result in the cutting of a nerve. Diagnosis The diagnosis of Neuromas is made by a physical exam and a thorough history of the patient's complaint. Conditions that mimic the pain associated with Neuromas are stress fracture of the metatarsals, inflammation of the tendons in the bottom of the toes, arthritis of the joint between the metatarsal bone and the toe, or nerve compression or nerve damage further up on the foot, ankle, knee, hip, or back. X-rays are generally taken to rule out a possible stress fracture or arthritis. Because nerve tissue is not seen on an x-ray, the x-ray will not show the neuroma. A skilled foot specialist will be able to actually feel the neuroma on his exam of the foot. Special studies such as MRI, CT scan, and nerve conduction studies have little value in the diagnosis of a neuroma. Additionally, these studies can be very expensive and generally the results do not alter the doctor's treatment plan. If the doctor on exam cannot feel the neuroma, and if the patient's symptoms are not what is commonly seen, then nerve compression at another level should be suspected. In this instance, one area to be examined is the ankle. Just below the ankle bone on the inside of the ankle, a large nerve passes into the foot. At this level, the nerve can become inflamed. This condition is called Tarsal Tunnel Syndrome. Generally, there is not pain at this site of the inflamed nerve at the inside of the ankle. Pain may instead be experienced in the bottom of the foot or in the toes. This can be a difficult diagnosis to make in certain circumstances. Neuromas, however, occur more commonly than Tarsal Tunnel Syndrome. Treatment Treatment for the neuroma consists of cortisone injections, orthotics, chemical destruction of the nerve, or surgery. Cortisone injections are generally used as an initial form of treatment. Cortisone is useful when injected around the nerve, because is can shrink the swelling of the nerve. This relieves the pressure on the nerve. Cortisone may provide relief for many months, but is often not a cure for the condition. The abnormal movements of the metatarsal bones continue to aggravate the condition over a period of time. To address the abnormal movement of the metatarsal bones, a functional foot orthotic can be used. These devices are custom-made inserts for the shoes that correct abnormal function of the

4 foot. The combination treatment of cortisone injections and orthotics can be a very successful form of treatment. If, however, there is significant damage to the nerve, then failure to this treatment can occur. When there is permanent nerve damage, the patient is left with three choices: live with the pain, chemical destruction of the nerve, or surgical removal or decompression of the nerve. Tarsal Tunnel Syndrome Tarsal Tunnel Syndrome is due to compression of a nerve called the Posterior Tibial Nerve.The nerve passes into the foot from around the inside of the ankle just below the ankle bone. Just beyond this point, the nerve enters the foot by passing between a muscle and a bone in the foot. This area is called the Tarsal Tunnel. The Posterior Tibial Nerve is the largest nerve that enters the foot. At the level of the ankle, the nerve branches out like the branches of a tree as it goes out toward the toes. This nerve supplies most of the sensation to the bottom of the foot and the muscles in the bottom of the foot. When pressure is placed on this nerve, a burning or numbness will be experienced on the bottom of the foot. The area of the bottom of the foot that is affected can be variable. Most commonly, it affects the outside portion of the bottom of the foot. It can also affect the toes, mimicking a neuroma. The most common cause of Tarsal Tunnel Syndrome is a flat foot or a foot in which the arch flattens excessively while walking. Over time, this causes the nerve to stretch or become compressed in the area of the tarsal tunnel. The condition is slowly progressive and occurs more commonly after 30 to 40 years of age. Other causes of Tarsal Tunnel Syndrome are the formation of soft tissue masses such as ganglions, fibromas, or lipomas that may occur in the Tarsal Tunnel and cause compression of the nerve. Also, small varicose veins may form around the nerve that can also cause compression of the nerve. Flattening of the arch of the foot is due to an abnormal function of a joint complex called the Subtalar Joint. This joint complex is located just below the ankle joint. When this joint allows the foot to flatten excessively, the foot becomes over pronated. Pronation is a normal movement of the foot, but when it occurs too much of the time, it causes several different problems to occur in the foot, one of them being Tarsal Tunnel Syndrome. Diagnoses Diagnosis of Tarsal Tunnel Syndrome is made by physical exam and the patient s history of their complaint. A history of gradual and progressive burning on the bottom of the foot should alert the doctor to the possible diagnoses. Physical exam will often reveal a flat foot or over-pronation of the foot that is observed when the patient walks. Observation of the area just below the ankle bone on the inside of the ankle may reveal a slight swelling. Tapping with the tips of the fingers or a neurological hammer in this area may reveal a tingling sensation in the bottom of the foot. X-rays may be of little value, because they will not show the nerve or reveal any evidence of soft tissue masses. X-rays may be useful in determining the extent of pronation of the foot but only if the x-ray is taken with the patient bearing full weight on the foot. An MRI may reveal the existence of a soft tissue mass, but will not demonstrate any damage to the nerve. Nerve

5 conduction studies will reveal if there is damage to the Posterior Tibial Nerve, but will be negative in the early stages of the condition. Other conditions that may cause similar symptoms are diabetic neuropathy, alcoholic neuropathy, or nerve compression at a level higher than the ankle. Poor circulation can also cause burning of the feet. If you experience these symptoms, you should consult your doctor at the earliest possible time. Treatment Treatment of Tarsal Tunnel Syndrome is directed at correcting the abnormal pronation of the foot. This is accomplished with functional foot orthotics. These devices are custom-made inserts for the shoes that correct abnormal function of the foot. Treatment with oral anti-inflammatory medications, vitamin B supplements, or steroids may provide some benefit, but are rarely curative. Calf muscle stretching can be useful, because it eases the tension and strain about the ankle joint. If the Tarsal Tunnel Syndrome is caused by a soft tissue mass, then surgical removal of the mass may be necessary. Surgical correction of Tarsal Tunnel Syndrome in the absence of a soft tissue mass has a very low success rate. This surgery, called nerve decompression, is intended to release the pressure on the nerve by freeing the soft tissue structures about the nerve as it passes through the tarsal tunnel. (See surgical Exploration for Tarsal Tunnel Syndrome) This surgery does not correct the over-pronation of the foot, however, and functional foot orthotics should be worn following the surgery. When there has been significant damage to the nerve, permanent nerve damage may be present. In this case, a complete cure is very unlikely, and treatment is directed at easing the symptoms. Certain medications available, by prescription from your doctor, may be beneficial for the burning pain that may be experienced at night. Magnetic insole therapy and Galvanic Nerve Stimulation are alternative forms of treatment that may provide relief. A referral to a pain medicine specialist may also be necessary. All articles provided by PodiatryNetwork.com