We are covering the nervous system in Applied Anatomy, and one of the diseases we have discussed is multiple scleroris (MS). I'm sure that most people have heard of MS or know someone that has this disease, but may not truly understand it. To really understand MS, we first have to discuss the axon. The axon is the long, cylindrical process of a neuron (nerve cell) that transmits the signal to the next neuron or muscle. Many axons are covered by a myelin sheath, which is made of lipids. The myelin sheath insulates the axon and increases nerve conduction velocity, meaning the signal travels down the axon faster with myelin. Multiple scleroris is a disease of the central nervous system (CNS). The myelination degenerates, and causes sclerosis (hardening) to occur at different places along the axon. In a way, MS is similar to atherosclerosis, in which arteries become hardened and blood flow is reduced or cut off. With MS, the nerve signal is either transmitted very slowly or not at all. MS affects both sensory neurons and motor neurons. Most people are diagnosed with MS between the ages of 20-40. The original symptoms are typically transient, unilateral blindness, or double vision. MS is diagnosed with a lumbar puncture. Because the nerve signal cannot reach the muscle, atrophy will occur (wasting away of skeletal muscle). Persons with MS will also have difficulty with fine motor movements and whole body coordination. There is no known treatment for MS, but most people can live fairly normal lives if the symptoms are managed properly. Here is an article on a former Auburn football player I worked with and his life with multiple sclerosis.
