George Huntington, On Chorea

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George Huntington (1850-1916) was a medical practitioner in Dutchess County New York.

His father and grandfather had both been doctors, and his family had lived on Long Island since 1797.

He gave his classic presentation, “On Chorea”, at the Meiga and Mason Academy of Medicine in Middleport Ohio in 1972, and this was subsequently published in the Medical and Surgical Reporter of Philadelphia on April 13, 1872.

This took place just one year after he graduated from his medical training at Columbia University.

He later explained his interest in the condition that now bears his name:

Over 50 years ago, in riding with my father on his rounds, I saw my first case of the “disorder”, which is the way the natives always referred to the dreaded disease.  I recall it as vividly as though it had just occurred but yesterday.  It made a most enduring impression on my boyish mind, an impression which was the very first impulse to my choosing chorea as my virgin contribution to the medical lore.  Driving with my father through a wooded road leading from East Hampton to Amagansett we suddenly came upon two women both bowing, twisting, grimacing.  I stared in wonderment, almost in fear.  What could it mean?  My father paused to speak with them and we passed on.  Then my Gamaliel-like instruction began; my medical instruction had its inception.  From this point on my interest in the disease has never wholly ceased.

Huntington’s disease (HD) is now know to be caused by a genetic mutation.  It is inherited in an autosomal dominant fashion, so that any child of an affected person typically has a 50% chance of inheriting the disease.  The mutation is a triplet repeat, so the genetics of HD lead to anticipation, a phenomenon whereby the disease may begin earlier and more severely in each successive generation.

HD can present at any age, but most often begins around 35-44 years with psychiatric disturbance such as depression or forgetfulness.  Neurological manifestations such as unsteady gait and the  jerky body movements (chorea) noted by George Huntington come later, followed by a progressive dementia.

Genetic testing is available, but pre-symptomatic testing for family members, who are at increased risk for the disease, is controversial since there is no treatment for HD.

Find out more about HD from the Huntington’s Disease Society of America.

Intrathecal Baclofen Infusion For Spasticity

Posted by Ilya Shnaydman, Drexel University College of Medicine Class of 2013:

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Spasticity is defined as a ‘stiffness’ or ‘tightness’ of muscle due to spasms, or increased muscular tone. It is usually due to a lack of inhibition, as seen in an upper motor neuron lesion affecting the brain or spinal cord. Examples of upper motor neuron lesions include stroke (cerebrovascular infarct), multiple sclerosis, traumatic brain injury and cerebral palsy.

Although the exact cause of spasticity is not know, it is theorized to be due to an imbalance between the excitatory and inhibitory input to a muscle group. Increased excitability leads to spasticity, whereas increased inhibition leads to a flaccid muscle.

IS2_cerebral_spasticityThis can be better understood by illustrating the popular ‘knee jerk reflex’. During this test, the examiner strikes the patellar ligament with a reflex hammer which stretches specialized sensory fibers called the muscle spindle. This produces a signal which travels to the spinal cord (specifically at the L4 level). From the spinal cord, another specialized nerve complex called the ‘alpha-motor neuron’ conducts an impulse back to the quadriceps femoris muscle which triggers the contraction (knee jerk).

IS2_preflexOne of the patients treated at Monmouth Medical Center by the Neurology Specialists of Monmouth County, TM (the patient’s name is hidden to preserve anonymity)  is a 65 year old male who suffers from a spinal cord infarct 15 years ago, which resulted in spasticity of his lower extremities (legs) just as described above. The right side has been affected more than the left.  He has difficulty walking, as his gait is very rigid, but does manage to get around using a cane.

For spasticity, medical treatment consists primarily of physical therapy and muscle relaxants such as baclofen, benzodiazepines, and even botulinum injections. When these methods have been exhausted and either do not work to the patient’s satisfaction or cause side effects, patient’s must turn to experts in the treatment of spasticity.

The patient’s multidisciplinary neuroscience physicians at Monmouth Medical center urged the patient to consider intrathecal baclofen to help the patient improve his gait and overall quality of life. By injecting baclofen directly into the spinal canal (where the spinal cord lays), his neurologists are able to give significantly lower doses of the medication (as it directly contacts the spinal cord) and prevent unwanted side effects.

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Baclofen is infused into the spinal canal via a programmable pump that is implanted beneath the skin (similar to a pacemaker). The pump’s batteries last about 10 years and most patients do not notice any discomfort from having the pump implanted. The baclofen is replenished by injecting it into the pump’s port (yellow arrow) with a small needle.

IS2_F3.large2Before undergoing surgery for placement of the baclofen pump, patients typically undergo a trial to see if the intrathecal baclofen will be beneficial to them. During this ‘trial’, baclofen is injected directly into the spinal canal during a spinal tap (lumbar puncture, or needle placed through the skin into the spinal canal). The patient is then observed over a few hours to see if they are a good candidate for the permanent intrathecal baclofen pump. During the trial, only a small dose of baclofen is used, so once the pump is placed and programmed, the patient can expect to see even more benefit from the therapy. After the pump has been placed it can be adjusted non-invasively using a magnet (similar to a pacemaker) and should be followed by a neurologist to adjust the dosage as needed.

Below you can see the effect of the baclofen trial (again with just a small dose) for our patient, TM