Neuromuscular disorders are diverse and can be difficult to identify. The care team at Mount Auburn Hospital’s Neuromuscular Disorders Clinic uses state-of-the art technology to assess, evaluate, and diagnose these complex neuromuscular diseases. Being diagnosed with a neuromuscular disorder can be life-altering. Our patient-centered care teams work with you and your family to provide the information necessary to make well-informed decisions about your healthcare treatment. We offer compassionate care to enable patients to address the physical and emotional challenges they may encounter.
Sui Li, MD
Sui Li, MD received his Medical Degree from the University of Massachusetts School of Medicine. He completed his Residency in Neurology at Tufts University Medical Center. Dr. Li also completed a Fellowship in Clinical Neurophysiology at Lahey Hospital & Medical Center and Boston Children’s Hospital. Dr. Li is Board Certified in Neurology and Clinical Neurophysiology and is fluent in Cantonese.
Katherine Wang, MD
Dr. Katherine K. Wang, Clinical Assistant Professor, Harvard Medical School, specializes in neurology at Mount Auburn Hospital with subspecialties in neuromuscular diseases, electromyography (EMG), and Botox injection. As a practicing physician for over 25 years, Dr. Wang has a particular clinical interest in Botox treatments of neurological disorders.
Edward Wolpow, MD
Dr. Edward Wolpow, Director of the Electromyography (EMG) Lab, has been a valued neurologist seeing patients at Mount Auburn Hospital since 1977. His clinical interests include epilepsy, electroencephalography (EEG), neuromuscular diseases, and stroke. He has lectured in clinical neurology at institutions including Harvard Medical school, MIT, and Boston University. Dr. Wolpow has taught the Clinical Neurology course in the Physician Assistant program at Northeastern University for more than 20 years, and has twice won the excellence in Teaching Award at Mount Auburn Hospital. He is past president of the National Puzzlers League.
The team also works with experts in:
- Pain Management
- Physical therapy
- Occupational therapy
- Plastic surgery
- Respiratory Medicine
- Speech Therapy
About Neuromuscular Disorders
The neuromuscular system is made up of the nerves and muscles in the body that communicate and work together to allow movement. The nerves act as a conduit of electrical signals that are generated by neurons in the brain and the spinal cord. Neurons are divided into upper motor neurons (nerve cells in the brain) which communicate with lower motor neurons (nerve cells in the brain stem and spinal cord). For movement to occur, a signal is sent from the upper motor neurons to the lower motor neurons, which then continue the signal to the muscle via the nerves. Neuromuscular disorders occur when one or more of those parts (upper motor neurons, lower motor neurons, nerves, or muscles) do not work properly or when they do not communicate with each other correctly.
Disorders of the neuromuscular system are classified into 4 groups: motor neuron diseases, neuropathies, neuromuscular junction disorders, and myopathies.
Motor neuron diseases
Motor neuron diseases (MND) cause progressive damage to either the upper motor neurons, the lower motor neurons, or both. As signals from the brain gradually stop reaching the muscles, the muscles also gradually stop working. MND can affect a person’s ability to walk, speak, breathe, eat, or drink. Although MNDs can happen in both children and adults, most cases begin after age 50.
Amyotrophic lateral sclerosis (ALS), or Lou Gehrig’s disease, is the most common form of MND. Other forms include spinal muscular atrophy, progressive muscular atrophy, primary lateral sclerosis, and progressive bulbar palsy
If your doctor or healthcare provider suspects you may have MND, they may do both a clinical and neurological exam. Depending on your symptoms, they may also order a blood test that looks for signs of muscle tissue breakdown. Tests that may be ordered that help determine how well your muscles are working are an EMG (electromyography) and a nerve conduction test. An MRI imaging study may also be ordered.
There is no known cause for most motor neuron diseases, but 5-10% of cases are inherited. There is no cure for MND.
Neuropathies are partial or total decreased functioning of nerves. Different types of neuropathy include peripheral neuropathy that affects nerves that control sensation, movement, and motor coordination, autonomic neuropathy that affects involuntary nerves that control heart beat and internal organs, and cranial neuropathy that affects the nerves in the brain stem. Neuropathy that happens to more than one group of nerves is called polyneuropathy. If the neuropathy happens in only one set or group of nerves, it is called focal neuropathy. Mononeuropathy affects a single nerve, such as cervical neuropathy or ulnar neuropathy.
In the U.S., it is estimated that almost 3% of the general population and 8% of those over age 55 have some form of neuropathy.
Factors or conditions that cause neuropathy include diabetes (known as diabetic neuropathy), genetic or inherited disorders, infections such as Lyme disease or HIV/AIDS, autoimmune disorders, exposure to chemicals that can damage nerves, physical trauma or injury, vitamin deficiency, or kidney failure. Pressure on a nerve or repetitive motion can also cause neuropathy. Post-herpetic neuralgia is a complication caused by the shingles virus.
Neuropathy symptoms can develop gradually and get progressively worse, or they can be acute and sudden if the cause is from an injury or fall. Symptoms can range from mild to severe. Although the most common symptom is muscle weakness, other symptoms include numbness, pain, slowed or decreased reflexes, burning sensation, muscle loss, and muscle cramping. More severe nerve injury can result in loss of function of certain parts of the body.
Most treatment modalities for neuropathy address the symptoms. Over-the-counter or prescription medications are sometimes used to relieve neuropathic pain. Physical therapy can help strengthen weakened muscles. Use of a transcutaneous electrical nerve stimulation (TENS) unit helps to relieve pain and inflammation. If the nerve damage is severe enough, surgery may be needed to repair the injured nerve.
Neuromuscular junction (NMJ) disorders
NMJ disorders are those that occur where the motor nerve and muscle connect and cause a malfunction in how the nerve communicates with the muscle tissue. Acetylcholine is the chemical messenger that transmits the signal from the nerve to the muscle. Once the signal is received by the muscle, the acetylcholine is broken down by the body so the signal does not continue to be transmitted. NMJ disorders occur when there is interference with how or how much acetylcholine is made, how it moves from the nerve to the muscle, how the muscle “reads” the signal, or how the body breaks it down to end the signal. Disorders of NMJ communication are classified into autoimmune or those where the body mistakenly attacks a part of the NMJ, toxic resulting from excess of an environmental or internal chemical, or genetic where the condition is inherited.
NMJ disorders result in tired or weak muscles that do not function properly. Affected muscles can include those that control walking, talking, swallowing, facial expression, and eye movement. Muscles that control breathing may also be affected.
Myasthenia gravis and Lambert-Eaton myasthenic syndrome are common autoimmune types of NMJ disorder. People with myasthenia gravis typically have double vision, droopy eyelids, and become unusually tired or weak after even mild exercise. The muscle weakness in people with myasthenia gravis goes away when the person is resting or not exercising. Those with Lambert- Eaton myasthenic syndrome have generalized fatigue and muscle weakness that does not go away with rest.
Blood tests and electromyography, a nerve test that records electrical activity in the muscles, are key investigative tools used to diagnose an NMJ disorder.
Treatment for NMJ disorders may include steroids to decrease inflammation or immunosuppressive medications, as well as treatment of the underlying cause.
Myopathies are diseases or conditions that damage muscles or cause problems with their ability to function. The damage interferes with the normal building, maintenance, and repair of muscle tissue. These disorders do not affect nerves at all, but some myopathies do involve cardiac or heart muscle.
Myopathies are classified as either genetic (inherited from your parents) or acquired (develops after you are born). The 3 major types of acquired myopathy are endocrine myopathy, inflammatory myopathy, and toxic myopathy.
Inherited myopathies are genetic conditions that prevent the building and maintenance of muscle tissue. The most common inherited myopathies are Duchenne muscular dystrophy and Becker muscular dystrophy which result from a genetic defect on the X chromosome. Other muscular dystrophies include limb girdle muscular dystrophy, facioscapulohumeral muscular dystrophy, and central nuclear myopathy.
Endocrine myopathies occur when an overabundance of hormones is produced by one of more of the body’s endocrine glands. For example, excess hormone production by the adrenal gland causes Cushing’s disease and Grave’s disease is caused by overproduction in the thyroid gland. In some cases, certain tumors produce hormones that cause endocrine myopathies.
Inflammatory myopathies occur when the body’s immune system attacks healthy muscle tissue resulting in chronic or long-term inflammation. The three main types of chronic inflammatory myopathy are polymyositis, dermatomyositis, and inclusion body myositis. Many inflammatory myopathies are present in people who also have other immune or rheumatic conditions such as rheumatoid arthritis or lupus.
Toxic myopathies are caused by external factors such as chemicals, toxins, alcohol, or certain medications. This type of myopathy can usually be reversed once the toxin is eliminated from the body.
Depending on the type of neuromuscular disorder, symptoms may include fatigue, weakness that can occur on one or both sides of the body, fever, dark urine caused by an accumulation of proteins when muscle tissue breaks down, muscle wasting or atrophy, muscle soreness, and pain.
To diagnose a neuromuscular disorder, your doctor will do a thorough history including review of any medications you may be taking and to determine if anyone in your family has an autoimmune disease, along with a physical exam and neurological exam. A blood test may be ordered to look for genetic indicators or for the presence of muscle breakdown byproducts. A nerve or muscle biopsy may be done to look at the current state or condition of that tissue. An EMG and nerve conduction tests may be performed, and imaging studies such as an MRI may be done.
Treatment for neuromuscular disorders depends on the exact type of disorder and its cause.
- Botulinum toxin therapy (chemodenervation)
Types of Diseases and Conditions We Treat
- Motor neuron disease
- Amyotrophic lateral sclerosis
- Spinal muscular atrophy
- Primary lateral sclerosis
- Primary muscle disorders
- Neuromuscular junction disorders
- Myasthenia gravis
- Congenital myasthenic syndromes
- Stiff-person syndrome
- Isaacs syndrome
- Nerve root disorders
- Peripheral nerve disorders and neuropathies
- Charcot-Marie-Tooth disease
- Guillain-Barré syndrome
- Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)
- Friedreich ataxia
- Peripheral nerve injuries and neuropathies caused by carpal tunnel syndrome
- Traumatic neuropathies
- Diabetic neuropathies
- Congenital myopathies
- Glycogen storage diseases
- Muscular dystrophies
- Duchenne muscular dystrophy
- Congenital muscular dystrophy
- Congenital myopathies
- Limb girdle muscular dystrophy
- Spinal muscular atrophy
- Charcot Marie Tooth disease
- Facioscapulohumeral muscular dystrophy
Amyotrophic Lateral Sclerosis (ALS) Association
Spinal Muscular Atrophy Foundation
Muscular Dystrophy Association
Facioscapulohumeral (FSH) Society
Congenital Muscle Disease International Patient Registry
Cure CMD, advocacy and education
United Mitochondrial Disease Foundation
Myasthenia Gravis Foundation of America
Friedreich’s Ataxia Research Alliance
Charcot-Marie Tooth Association