=Definition.=—A chronic affection of the spinal cord in which there
is an embryonal neurogliar overgrowth about the central canal, with
cavity formation. It is characterized, clinically, by progressive
muscular atrophy, peculiar disturbances of sensation and various
trophic and vasomotor disorders. The onset generally takes place before
the thirtieth year. Males are much more commonly affected than females.
It is claimed by some that the disease is infectious. It frequently
follows trauma.
=Pathologically=, the condition begins with an overgrowth of embryonal
neurogliar tissue. This is followed by degeneration of the gliomatous
tissue with a formation of cavities, or this cavity formation may be
the result of hemorrhage. The disease, in most cases, involves only
the cervical or dorsal regions, and is usually in the posterior or
postero-lateral tracts. The cavity may prevail throughout the entire
cord, but usually only the cervical and dorsal regions are involved.
The cavities lie in the gray matter outside of the canal.
=Symptoms.=—The onset is slow. The symptoms depend upon the situation
and extent of the cavity. As the disease most frequently involves the
cervical region, the neck and arms are usually affected. At first
neuralgic pains may develop in the muscles. Later there is progressive
muscular atrophy and loss of painful and thermic sensations. Tactile
and muscular senses are usually intact. The reflexes are increased and
a spastic condition is present. The lower limbs usually escape, but
when they are involved the clinical picture may be that of =amyotrophic
lateral sclerosis=. A lateral curvature is present. When the disease
extends into the medulla, there will be various bulbar symptoms.
Trophic changes and vasomotor disorders are common.
A form of syringomyelia, known as =Morvan’s disease=, is characterized
by neuralgic pains, cutaneous anesthesia and painless felons.
=Diagnosis.=—The progressive muscular atrophy, the retention of
muscular and tactile senses, and the loss of thermic and painful
sensations are typical symptoms. The diseases with which it may be
confounded are: =Cervical Pachymeningitis.= The pain is usually
greater, the tactile sense is lost and it runs a more rapid course.
=Anesthetic Leprosy.= The trophic changes are more marked, tactile
sensation is lost and the phalanges often drop off. =Progressive
Muscular Atrophy= and =Amyotrophic Lateral Sclerosis=. Sensory symptoms
are wanting.
=Prognosis.=—The prognosis is unfavorable. Duration is from five to
twenty years.
=Treatment.=—Little can be done except attending to the diet and
hygiene of the patient and meeting urgent symptoms. Probably, continued
treatment along the spinal column would influence to some extent
the circulation of the cord in the region of the involvement. Hot
applications are of value in relieving pain and cramps. The X-ray has
proven of some benefit in checking the progress of the disease.