Neurological Disorders

Myoclonus

Myoclonus refers to a sudden, involuntary jerking of a muscle or group of muscles. In its simplest form, myoclonus consists of a muscle twitch followed by relaxation.

A hiccup is an example of this type of myoclonus. Other familiar examples of myoclonus are the jerks or “sleep starts” that some people experience while drifting off to sleep. These simple forms of myoclonus occur in normal, healthy persons and cause no difficulties.

When more widespread, myoclonus may involve persistent, shock-like contractions in a group of muscles. Myoclonic jerking may develop in people with:

Simple forms of myoclonus occur in normal, healthy persons and cause no difficulties. In some cases, myoclonus begins in one region of the body and spreads to muscles in other areas. More severe cases of myoclonus can distort movement and severely limit a person’s ability to eat, talk, or walk. These types of myoclonus may indicate an underlying disorder in the brain or nerves.

Treatment of myoclonus focuses on medications that may help reduce symptoms. The drug of first choice is clonazepam, a type of tranquilizer. Many of the drugs used for myoclonus, such as barbiturates, phenytoin, and primidone, are also used to treat epilepsy. Sodium valproate is an alternative therapy for myoclonus and can be used either alone or in combination with clonazepam.

Although clonazepam and sodium valproate are effective in the majority of people with myoclonus, some people have adverse reactions to these drugs. The beneficial effects of clonazepam may diminish over time if the individual develops a tolerance for the drug. Myoclonus may require the use of multiple drugs for effective treatment.

Muscular Dystrophy

The muscular dystrophies (MD) are a group of more than 30 genetic diseases characterized by progressive weakness and degeneration of the skeletal muscles that control movement.

Some forms of MD are seen in infancy or childhood, while others may not appear until middle age or later.

The disorders differ in terms of the distribution and extent of muscle weakness (some forms of MD also affect cardiac muscle), age of onset, rate of progression, and pattern of inheritance.

There is no specific treatment to stop or reverse any form of MD. Treatment may include:

  • Physical therapy
  • Respiratory therapy
  • Speech therapy
  • Orthopedic appliances used for support
  • Corrective orthopedic surgery

Drug therapy includes:

  • Corticosteroids to slow muscle degeneration
  • Anticonvulsants to control seizures and some muscle activity
  • Immunosuppressants to delay some damage to dying muscle cells
  • Antibiotics to fight respiratory infections

Some individuals may benefit from occupational therapy and assistive technology. Some patients may need assisted ventilation to treat respiratory muscle weakness and a pacemaker for cardiac abnormalities.

The prognosis for people with MD varies according to the type and progression of the disorder. Some cases may be mild and progress very slowly over a normal lifespan, while others produce severe muscle weakness, functional disability, and loss of the ability to walk. Some children with MD die in infancy while others live into adulthood with only moderate disability.

Duchenne Muscular Dystrophy

Duchenne MD (DMD) is the most common form of MD, affecting one in 4000 males. It is caused by the absence of dystrophin, a protein involved in maintaining the integrity of muscle.

DMD primarily affects boys. Onset is between 3 and 5 years and the disorder progresses rapidly. Most boys are unable to walk by age 12, and later need a respirator to breathe.

Girls in these families have a 50 percent chance of inheriting and passing the defective gene to their children.

Boys with Becker MD (very similar to but less severe than Duchenne MD) have faulty or not enough dystrophin.

The average life expectancy for patients afflicted with DMD varies from late teens to early to mid 20s. There have been reports of a few DMD patients surviving to the age of 40, but this is extremely rare.

Facioscapulohumeral Muscular Dystrophy

Facioscapulohumeral MD causes progressive weakness in muscles of the face, arms, legs, and around the shoulders and chest. It progresses slowly and can vary in symptoms from mild to disabling.

Facioscapulohumeral MD usually begins in the teenage years.

Life expectancy is normal, but up to 15% of affected individuals become severely disabled and eventually must use a wheel chair.

Myotonic Dystrophy

Myotonic MD is the disorder’s most common adult form, although Myotonic dystrophy can occur in patients of any age.

It is typified by:

  • Prolonged muscle spasms
  • Cataracts
  • Cardiac abnormalities
  • Endocrine disturbances

Individuals with myotonic MD have long, thin faces, drooping eyelids, and a swan-like neck.

Multifocal Motor Neuropathy

Multifocal motor neuropathy is a progressive muscle disorder. It is characterized by muscle weakness in the hands, with differences from one side of the body to the other in the specific muscles involved.

Multifocal motor neuropathy is a very rare condition, affecting only about 1 per 100,000 people in the population. Multifocal motor neuropathy affects men about three times more than women. Most patients are between the ages of 30 and 50 when symptoms are noted, with the average age of onset being 40 years.

Multifocal motor neuropathy is thought to result from an autoimmune disorder.

Besides muscle weakness in the hands, symptoms also include:

  • Muscle wasting
  • Cramping
  • Involuntary contractions or twitching of the leg muscles

The disorder is sometimes mistaken for amyotrophic laterial sclerosis (ALS, or Lou Gehrig’s disease) but unlike ALS, it is treatable. An early and accurate diagnosis allows patients to recover quickly.

Treatment for multifocal motor neuropathy varies. Some individuals experience only mild, modest symptoms and require no treatment. For others, treatment generally consists of intravenous immunoglobulin (IVIg) or immunosuppressive therapy with cyclophosphamide.

Improvement in muscle strength usually begins within 3 to 6 weeks after treatment is started. Most patients who receive treatment early experience little, if any, disability. However, there is evidence of slow progression over many years.

Traumatic Brain Injury

Traumatic brain injury (TBI), a form of acquired brain injury, occurs when a sudden trauma causes damage to the brain.

TBI can result when the head suddenly and violently hits an object, or when an object pierces the skull and enters brain tissue.

Symptoms of a TBI can be mild, moderate, or severe, depending on the extent of the damage to the brain. A person with a mild TBI may remain conscious or may experience a loss of consciousness for a few seconds or minutes. Other symptoms of mild TBI include:

  • Headache
  • Confusion
  • Lightheadedness
  • Dizziness
  • Blurred vision or tired eyes
  • Ringing in the ears
  • Bad taste in the mouth
  • Fatigue or lethargy
  • A change in sleep patterns
  • Behavioral or mood changes
  • Trouble with memory, concentration, attention, or thinking

A person with a moderate or severe TBI may show these same symptoms, but may also have:

  • headache that gets worse or does not go away
  • Repeated vomiting or nausea
  • Convulsions or seizures
  • An inability to awaken from sleep
  • Dilation of one or both pupils of the eyes
  • Slurred speech
  • Weakness or numbness in the extremities
  • Loss of coordination
  • Increased confusion, restlessness, or agitation

Anyone with signs of moderate or severe TBI should receive medical attention as soon as possible.

Imaging tests help in determining the diagnosis and prognosis of a TBI patient. Patients with mild to moderate injuries may receive skull and neck X-rays to check for bone fractures or spinal instability. For moderate to severe cases, the imaging test is a computed tomography (CT) scan.

Disabilities resulting from a TBI depend upon the severity of the injury, the location of the injury, and the age and general health of the individual. Some common disabilities include:

  • Problems with cognition (thinking, memory, and reasoning)
  • Problems with sensory processing (sight, hearing, touch, taste, and smell)
  • Problems with communication (expression and understanding)
  • Behavior or mental health issues – depressionanxiety, personality changes, aggression, acting out, and social inappropriateness

More serious head injuries may result in:

  • Stupor – an unresponsive state, but one in which an individual can be aroused briefly by a strong stimulus, such as sharp pain
  • Coma – a state in which an individual is totally unconscious, unresponsive, unaware, and unarousable
  • Vegetative state – in which an individual is unconscious and unaware of his or her surroundings, but continues to have a sleep-wake cycle and periods of alertness
  • Persistent vegetative state (PVS) – in which an individual stays in a vegetative state for more than a month

Because little can be done to reverse the initial brain damage caused by trauma, medical personnel try to stabilize an individual with TBI and focus on preventing further injury. Primary concerns include insuring proper oxygen supply to the brain and the rest of the body, maintaining adequate blood flow, and controlling blood pressure.

Moderately to severely injured patients receive rehabilitation that involves individually tailored treatment programs in the areas of physical therapy, occupational therapy, speech/language therapy, physiatry (physical medicine), psychology/psychiatry, and social support. Approximately half of severely head-injured patients will need surgery to remove or repair hematomas (ruptured blood vessels) or contusions (bruised brain tissue).

Transverse Myelitis

Transverse myelitis is a neurological disorder caused by inflammation across both sides of one segment of the spinal cord. The term myelitis refers to inflammation of the spinal cord; transverse simply describes the position of the inflammation, that is, across the width of the spinal cord. Attacks of inflammation can damage or destroy myelin, the fatty insulating substance that covers nerve cell fibers. This damage causes nervous system scars that interrupt communications between the nerves in the spinal cord and the rest of the body.

Symptoms of transverse myelitis include a loss of spinal cord function over several hours to several weeks. What usually begins as a sudden onset of lower back pain, muscle weakness, or abnormal sensations in the toes and feet can rapidly progress to more severe symptoms, including paralysis, urinary retention, and loss of bowel control.

The segment of the spinal cord at which the damage occurs determines which parts of the body are affected. Nerves in the cervical (neck) region control signals to the neck, arms, hands, and muscles of breathing (the diaphragm). Nerves in the thoracic (upper back) region relay signals to the torso and some parts of the arms. Nerves at the lumbar (mid-back) level control signals to the hips and legs. Finally, sacral nerves, located within the lowest segment of the spinal cord, relay signals to the groin, toes, and some parts of the legs. Damage at one segment will affect function at that segment and segments below it. In patients with transverse myelitis, demyelination usually occurs at the thoracic level, causing problems with leg movement and bowel and bladder control, which require signals from the lower segments of the spinal cord.

Transverse myelitis occurs in adults and children, in both genders, and in all races. No familial predisposition is apparent. A peak in incidence rates appears to occur between 10 and 19 years and 30 and 39 years. It is estimated that about 1,400 new cases of transverse myelitis are diagnosed each year in North America, and approximately 33,000 North Americans have some type of disability resulting from the disorder.

Researchers are uncertain of the exact causes of transverse myelitis. The inflammation that causes such extensive damage to nerve fibers of the spinal cord may result from:

  • Viral infections
  • Abnormal immune reactions
  • Insufficient blood flow through the blood vessels located in the spinal cord

Transverse myelitis also may occur as a complication of syphilis, measles, Lyme disease, and some vaccinations, including those for chickenpox and rabies. Cases in which a cause cannot be identified are called idiopathic.

Transverse myelitis may be either acute (developing over hours to several days) or subacute (developing over 1 to 2 weeks). Symptoms may include:

  • Localized lower back pain
  • Sudden paresthesias – abnormal sensations such as burning, tickling, pricking, or tingling in the legs
  • Sensory loss
  • Paraparesis – partial paralysis of the legs
  • Paraplegia – paralysis of the legs and lower part of the trunk
  • Urinary bladder and bowel dysfunction
  • Muscle spasms
  • A general feeling of discomfort
  • Headache
  • Fever
  • Loss of appetite

Depending on which segment of the spinal cord is involved, some patients may experience respiratory problems as well.

From this wide array of symptoms, four classic features of transverse myelitis emerge:

  1. Weakness of the legs and arms
  2. Pain
  3. Sensory alteration
  4. Bowel and bladder dysfunction

Recovery from transverse myelitis usually begins within 2 to 12 weeks of the onset of symptoms and may continue for up to 2 years. However, if there is no improvement within the first 3 to 6 months, significant recovery is unlikely. About one-third of people affected with transverse myelitis experience good or full recovery from their symptoms; they regain the ability to walk normally and experience minimal urinary or bowel effects and paresthesias. Another one-third show only fair recovery and are left with significant deficits such as spastic gait, sensory dysfunction, and prominent urinary urgency or incontinence. The remaining one-third show no recovery at all, remaining wheelchair-bound or bedridden with marked dependence on others for basic functions of daily living. Research has shown that a rapid onset of symptoms generally results in poorer recovery outcomes.

Although some patients recover from transverse myelitis with minor or no residual problems, others suffer permanent impairments that affect their ability to perform ordinary tasks of daily living. Most patients will have only one episode of transverse myelitis; a small percentage may have a recurrence.

As with many disorders of the spinal cord, no effective cure currently exists for people with transverse myelitis. Treatments are designed to manage and alleviate symptoms and largely depend upon the severity of neurological involvement. Physicians often prescribe corticosteroid therapy during the first few weeks of illness to decrease inflammation. General analgesia will likely be prescribed for any pain the patient may have. And bedrest is often recommended during the initial days and weeks after onset of the disorder.

Following initial therapy, the most critical part of the treatment for this disorder consists of keeping the patient’s body functioning while hoping for either complete or partial spontaneous recovery of the nervous system. This may sometimes require placing the patient on a respirator. Many forms of long-term rehabilitative therapy are available for people who have permanent disabilities resulting from transverse myelitis, including:

  • Physical Therapy
  • Occupational Therapy
  • Vocational Therapy

Todds Paralysis

Todd’s paralysis, also known as Epileptic Hemiplegia, is a neurological condition experienced by individuals with epilepsy, in which a seizure is followed by a brief period of temporary paralysis.

Scientists don’t know what causes Todd’s paralysis. Current theories propose biological processes in the brain that involve a slow down in either the energy output of neurons or in the motor centers of the brain.

Todd’s paralysis may occur in up to 13% of seizure cases. It is most common after generalised tonic-clonic seizures. The paralysis may be partial or complete but usually occurs on just one side of the body. The paralysis can last from half an hour to 36 hours, with an average of 15 hours, at which point it resolves completely. Todd’s paralysis may also affect speech and vision.

It is important to distinguish Todd’s paralysis from a stroke, which it can resemble, because a stroke requires completely different treatment.

Todd’s paralysis is an indication that an individual has had an epileptic seizure. The outcome depends on the effects of the seizure and the subsequent treatment of the epilepsy.

There is no treatment for Todd’s paralysis. Individuals must rest as comfortably as possible until the paralysis disappears.

Thoracic Outlet Syndrome

Thoracic Outlet Syndrome (TOS) is an umbrella term that encompasses three related syndromes that cause pain in the arm, shoulder, and neck:

  • Neurogenic TOS – caused by compression of the brachial plexus
  • Vascular TOS – caused by compression of the subclavian artery or vein
  • Nonspecific or disputed TOS – in which the pain is from unexplained causes

Occasionally, neurogenic TOS and vascular TOS co-exist in the same person.

TOS is more common in women. The onset of symptoms usually occurs between 20 and 50 years of age.

Neurogenic TOS has a characteristic sign, called the Gilliatt-Sumner hand, in which there is severe wasting in the fleshy base of the thumb. There may be numbness along the underside of the hand and forearm, or dull aching pain in the neck, shoulder, and armpit.

Vascular TOS features pallor, a weak or absent pulse in the affected arm, which also may be cool to the touch and appear paler than the unaffected arm. Symptoms may include numbness, tingling, aching, and heaviness.

Non-specific TOS most prominently features a dull, aching pain in the neck, shoulder, and armpit that gets worse with activity. Non-specific TOS is frequently triggered by a traumatic event such as a car accident or a work related injury. It also occurs in athletes, including weight lifters, swimmers, tennis players, and baseball pitchers.

Making the diagnosis of TOS is difficult because a number of disorders feature symptoms similar to those of TOS, including:

Doctors usually recommend nerve conduction studies, electromyography, or imaging studies to confirm or rule out a diagnosis of TOS.

The disorder can sometimes be diagnosed in a physical exam by tenderness in the supraclavicular area, weakness and/or a “pins and needles” feeling when elevating the hands, weakness in the fifth (“little”) finger, and paleness in the palm of one or both hands when the individual raises them above the shoulders, with the fingers pointing to the ceiling. Symptoms of TOS vary depending on the type.

Treatment begins with exercise programs and physical therapy to strengthen chest muscles, restore normal posture, and relieve compression by increasing the space of the area the nerve passes through. Doctors will often prescribe non-steroidal anti-inflammatory drugs (such as naproxen or ibuprofen) for pain. If this doesn’t relieve pain, a doctor may recommend thoracic outlet decompression surgery to release or remove the structures causing compression of the nerve or artery.

The outcome for individuals with TOS varies according to type. The majority of individuals with TOS will improve with exercise and physical therapy. Vascular TOS, and true neurogenic TOS often require surgery to relieve pressure on the affected vessel or nerve.

Tethered Spinal Cord Syndrome

Tethered spinal cord syndrome is a neurological disorder caused by tissue attachments that limit the movement of the spinal cord within the spinal column. These attachments cause an abnormal stretching of the spinal cord.

Tethered spinal cord syndrome appears to be the result of improper growth of the neural tube during fetal development, and is closely linked to spina bifida. Tethering may also develop after spinal cord injury and scar tissue can block the flow of fluids around the spinal cord. Fluid pressure may cause cysts to form in the spinal cord, a condition called syringomyelia. This can lead to additional loss of movement, feeling or the onset of pain or autonomic symptoms.

The course of the disorder is progressive. In children, symptoms may include:

  • Lesions on the lower back
  • Hairy patches on the lower back
  • Dimples on the lower back
  • Fatty tumors on the lower back
  • Foot and spinal deformities
  • Weakness in the legs
  • Low back pain
  • Scoliosis
  • Incontinence

Tethered spinal cord syndrome may go undiagnosed until adulthood, when sensory and motor problems and loss of bowel and bladder control emerge. This delayed presentation of symptoms is related to the degree of strain placed on the spinal cord over time.

With treatment, individuals with tethered spinal cord syndrome have a normal life expectancy. However, some neurological and motor impairments may not be fully correctable.

In children, early surgery is recommended to prevent further neurological deterioration. If surgery is not advisable, spinal cord nerve roots may be cut to relieve pain. In adults, surgery to free (detether) the spinal cord can reduce the size and further development of cysts in the cord and may restore some function or alleviate other symptoms. Other treatment is symptomatic and supportive.

Tarlov Cysts

Tarlov cysts are sacs filled with cerebrospinal fluid that most often affect nerve roots in the sacrum, the group of bones at the base of the spine.

Women are at much higher risk of developing these cysts than are men.

These cysts (also known as meningeal or perineural cysts) can compress nerve roots, causing:

  • Lower back pain
  • Sciatica – shock-like or burning pain in the lower back, buttocks, and down one leg to below the knee
  • Urinary incontinence
  • Headaches – due to changes in cerebrospinal fluid pressure
  • Constipation
  • Sexual dysfunction
  • Some loss of feeling or control of movement in the leg and/or foot

Pressure on the nerves next to the cysts can also cause pain and deterioration of surrounding bone.

Tarlov cysts can be diagnosed using magnetic resonance imaging (MRI); however, it is estimated that 70% of the cysts observed by MRI cause no symptoms. Tarlov cysts may become symptomatic following shock, trauma, or exertion that causes the buildup of cerebrospinal fluid. Some scientists believe the herpes simplex virus, which thrives in an alkaline environment, can also cause Tarlov cysts to become symptomatic.

Most Tarlov cysts do not cause pain, weakness, or nerve root compression. Acute and chronic pain may require changes in lifestyle. If left untreated, nerve root compression can cause permanent neurological damage.

Tarlov cysts may be drained and shunted to relieve pressure and pain, but relief is often only temporary and fluid build-up in the cysts will recur. Corticosteroid injections may also temporarily relieve pain. Other drugs may be prescribed to treat chronic pain and depression. Injecting the cysts with fibrin glue (a combination of naturally occurring substances based on the clotting factor in blood) may provide temporary relief of pain. Making the body less alkaline, through diet or supplements, may lessen symptoms. Microsurgical removal of the cyst may be an option in select individuals who do not respond to conservative treatments and who continue to experience pain or progressive neurological damage.

Tardive Dyskinesia

Tardive dyskinesia is a neurological syndrome caused by the long-term use of neuroleptic drugs. Neuroleptic drugs are generally prescribed for psychiatric disorders, as well as for some gastrointestinal and neurological disorders.

Estimates suggest that it occurs in 15-30% of patients receiving treatment with antipsychotic neuroleptic medications for 3 months or longer. The elderly and female patients are more prone to develop tardive dyskinesia. Cigarette smokers also have a higher prevalence.

Tardive dyskinesia is characterized by repetitive, involuntary, purposeless movements. Features of the disorder may include:

  • Grimacing
  • Tongue protrusion
  • Lip smacking
  • Puckering
  • Pursing
  • Rapid eye blinking
  • Rapid movements of the arms, legs, and trunk
  • Involuntary movements of the fingers may appear as though the patient is playing an invisible guitar or piano

For comparison, patients with Parkinson’s disease have difficulty moving, while patients with tardive dyskinesia have difficulty not moving.

It’s often mistaken for “mental illness” rather than a neurological disorder and patients are prescribed wrong medication of offending neuroleptic drugs, which enhances probability that the patient will develop a severe and disabling case. That is why it is critical to properly identify signs of the disorder and stop neuroleptic treatment as early as possible.

There is no standard treatment for tardive dyskinesia. Treatment is highly individualized. The first step is generally to stop or minimize the use of the neuroleptic drug. However, for patients with a severe underlying condition this may not be a feasible option.

Replacing the neuroleptic drug with substitute drugs may help some patients. Other drugs such as benzodiazepines, adrenergic antagonists, and dopamine agonists may also be beneficial.

Symptoms of tardive dyskinesia may remain long after discontinuation of neuroleptic drugs; however, with careful management, some symptoms may improve and/or disappear with time.