Treating the Peripheral Nervous System
Anyone unfamiliar with the medical specialty of neurology might understandably assume that a referral to any neurologist is appropriate for any neurological condition. The fact is, however, that while all neurologists undergo training in all categories of neurological diseases and occasionally treat neurological cases of every description, there is considerable specialization within the field.
Basically, neurologists specialize in either the peripheral nervous system or the central nervous system. Neuromuscular disorders primarily fall under the former category and are treated locally by Dr. Gregory Blume and Dr. Christopher Zallek, neuromuscular neurologists with the Illinois Neurological Institute at OSF Saint Francis Medical Center. Examples of these disorders include carpal tunnel syndrome, muscular dystrophy and amyotrophic lateral sclerosis, commonly known as ALS or Lou Gehrig’s disease.
“With neuromuscular disorders, we focus on disorders or diseases affecting the nervous system outside the brain and spinal cord—anything from the nerve roots exiting the spinal cord, the network of nerves within the shoulder and the pelvis, and individual nerves running out to the muscles in the arms and legs,” explained Dr. Zallek. “We also look at problems at the connections between the nerves and the muscles and diseases of the muscles themselves. This does not include multiple sclerosis, stroke, seizures or sleep disorders,” he stressed.
According to Dr. Blume, the most common type of neuromuscular disorder is peripheral neuropathy, which afflicts some 15 to 20 million Americans. Due to deterioration of the peripheral nerves, it causes symptoms like weakness that progresses gradually, itching, tingling, burning, dizziness, clumsiness and a crawling sensation.
Untreated neuropathy can lead to numbness or constant pain, but many neuropathies are treatable or at least have manageable symptoms. The first step is early diagnosis and evaluation for potential causes.
“Estimates suggest that as many as 10 percent of Americans will eventually be diagnosed with or at least have symptoms of neuropathy,” Dr. Blume said. “The vast majority of people who are aware of the term neuropathy associate it with diabetes.
“However, in spite of the fact that diabetes is the most common cause of neuropathy, diabetic neuropathy accounts for only about 25 to 30 percent of neuropathy,” he continued. “Other types are inherited or are associated with other diseases, such as kidney failure, or with medications and toxins. There are a whole host of other types of neuropathy that we see, and we try to identify actual causes and ways to help with them.”
In diagnosing conditions, neuromuscular neurologists use EMG (electromyography) nerve connection studies. The first part of this test involves shocking the nerves to activate them in order for a computer to measure the nerve signal and how quickly it is transmitted.
“With that, we can tell if there is a problem with the nerve wires, such as diabetes, affecting them,” Dr. Zallek explained. “Is there a slowing of the nerve signal somewhere, just in one location, such as carpal tunnel syndrome? Is there an overall slowing of the nerve signals where insulation on the outside of the nerve is getting damaged?”
For the second phase of the test, a needle is inserted into muscles to determine how well they’re connected to the nerves and if the muscles are healthy. That allows neuromuscular neurologists to evaluate the severity of the neuropathy and to pinpoint the location of the problem.
The fact that the test involves shocking nerves and sticking needles into muscles tends to lead people to expect pain, according to Dr. Zallek. “But when the test is finished, the vast majority of them say that it wasn’t as bad as they thought it was going to be,” he said.
Nerve or muscle biopsies and imaging studies, including X-rays, MRIs and CT scans, may also be ordered in diagnosing neuromuscular conditions. In some cases, a surgical opinion might be requested.
A physician referral is needed in order for a patient to be seen by a neuromuscular neurologist. The referral may be based on symptoms reported to a primary care physician or on an abnormal lab test that suggests the possible existence of a neuromuscular condition, even in the absence of symptoms.
“Almost always with any of these conditions, there tends to be a time period early on when symptoms are mild or not readily apparent, making a diagnosis difficult,” Dr. Blume said. “One of the things that a neuromuscular physician does bring to the table, so to speak, is an awareness of what early symptoms can be important in the development of a significant neuromuscular disease down the road.”
Early diagnosis is key to achieving the best outcome, according to Dr. Blume. “Myasthenia gravis is an example of a neuromuscular disease that is very treatable and very easily maintained, at least in remission if it’s not curable, but it can be a devastating disease untreated,” he explained. “It can lead to significant disability and be potentially life-threatening if not treated appropriately.
“With early diagnosis, we can help people maintain their function or get back to a good functional level more quickly. The longer it is untreated and symptoms progress, the longer it’s going to take to get it in remission and get a person back to functioning correctly.”
Treatable conditions might involve medication, surgery, physical therapy or a recommendation that the patient try to maintain activity levels. For very serious conditions that do not respond to treatment, such as ALS, neuromuscular neurologists can help in other respects.
“There are often many things that arise in the course of a disease like ALS that, because of our background and having taken care of many, many people, we can help anticipate needs and help someone be as comfortable and functional as possible,” Dr. Blume said. “We can provide patients with knowledge about their condition so they can know what to expect and can plan accordingly. Sometimes, we can help with symptomatic treatment.” iBi