anesthesia is more decided in the former than in the latter. In the case of spinal hemorrhage the paralytic symptoms are more decided from the outset ; while in meningeal hemorrhage these are preceded by muscular spasm. Trophic changes characterize spinal hemorrhage, and are wanting in meningeal hemorrhage.

Spinal Compression.

What are the causes of compression of the spinal cord?

The cord may be compressed by tumors of the spinal canal; by dislocation of the vertebræ, independently, or as a result of caries, or of fracture; by an exostosis; by an aneurism that has eroded the bones; or by an hydatid cyst.

How can the causes of spinal compression be differentiated?

The recognition of a tumor in the spinal canal depends upon its detection from without, or the detection of new-growths in other parts of the body.

Simple dislocation and fracture of the vertebræ follow traumatism; the symptoms to which dislocation gives rise set in suddenly and are profound in degree; a deformity of the spinal column may be detectable.

The diagnosis of caries depends upon the knowledge of a history of syphilis or of tuberculosis and the detection of a painful deformity in the back.

An hydatid cyst of the spinal canal may be diagnosticated by the detection externally of a fluctuating tumor, upon puncture of which the characteristic hooklets may be found.

It may be impossible to diagnosticate the cause of compression of the cord dependent upon an exostosis or upon an aneurism.

To what symptoms does compression of the spinal cord give rise?

The rapidity with which the symptoms of compression appear depends somewhat upon the cause. *Dislocation is apt to occa sion manifestations of immediate gravity. In other cases, the symptoms are gradual in appearance and progressive in course,

Compression gives rise to two groups of phenomena, referable to the nerve-roots and to the cord, respectively. There is local pain in the back, aggravated by movement, as well as pains of a radiating character, with girdle-sensation; ultimately anesthesia develops. There is loss of motion in the parts supplied by the nerves from the cord below the seat of compression; with exaggerated reflexes and involvement of the sphincters. The palsied muscles slowly waste and degenerative reactions set in. Contractures may develop.

How is compression-myelitis to be distinguished from hemorrhage into the spinal cord?

When a vertebra softened by destructive disease suddenly gives way, the resulting displacement may be followed by compression of the cord, occasioning symptoms with which those produced by hemorrhage into the cord may be identical. The symptoms of compression, however, are usually more extensive and more absolute than those of hemorrhage; the existence of a deformity of the spine makes the diagnosis certain.

What are the distinctions between compression of the cord and chronic myelitis?

Symptoms of irritation referable to the nerve-roots are wanting in myelitis. The recognition of a cause of compression determines the diagnosis.

Tumor of the Spinal Cord.

What are the symptoms of tumor of the spinal cord?

Tumors of the spinal canal may be situated without or within the dura mater, or within the structure of the cord itself. They are most diverse in character. The symptoms will depend upon the situation of the tumor and upon the degree of mechanical interference with the functions of the cord that it occasions. Pressure on the nerve-roots gives rise to pain, to abnormal sensations, to girdle-pain and to muscular spasm and rigidity. Pressure on the cord or myelitis occasions anesthesia, paralysis and exaggerated reflexes below the level of the lesion and

abolition of the reflexes within the area innervated from the seat of the growth. Involvement of the anterior horns of the gray matter is attended with wasting and other trophic disorders; involvement of the lumbar enlargement causes abolition of the knee-jerk, loss of control of the sphincters and wasting and palsy in the lower extremities; involvement of the cervical enlargement occasions wasting and palsy in the upper extremities. The unilateral appearance of symptoms of spinal disease, or evidence of sensory derangement on one side and motor derangement on the other, is strongly suggestive of tumor of the spinal canal. With the growth of the tumor the

symptoms become bilateral.

From what conditions is spinal tumor to be distinguished? The diagnosis of spinal tumor includes the determination of the nature of the tumor and its distinction from other conditions presenting similar symptoms.

In the first connection, a history of syphilis, of tuberculosis, or of tumors situated elsewhere is to be considered.

The differentiation from caries of the vertebræ depends upon the recognition of disease of the bone, upon the deformity that results and upon the greater degree of pain on movement that attends caries.

From hypertrophic pachymeningitis spinal tumor differs in course; being progressive, while symptoms of irritation precede those of paralysis and wasting. The symptoms of pachymeningitis are more circumscribed in distribution than are those of tumor.

The symptoms of tumor differ from those of myelitis, in being irritative in character-attended by pain and spasm, rather than paralytic. If tumor give rise to myelitis, the recognition of the condition depends upon a knowledge of the previous symptoms.

The persistence of obstinate neuralgia, especially if bilateral, should excite suspicion of spinal tumor.

Syringomyelia.

What are the symptoms of syringomyelia?

Cavities in the spinal cord may be a result of defective apposition of the lateral halves of the cord in the course of development; of occlusion of the central canal, with accumulative distention by cerebro-spinal fluid; of the disintegration of gliomata; or they may appear subsequently to myelitis. The course of the disease is slow and chronic, sometimes covering many years. The symptoms vary somewhat with the situation of the cavity. They are usually most conspicuous in the upper extremities. There are muscular wasting and weakness, preceded by alterations of sensation. Common sensibility is usually preserved, while the perception of pain and of heat and cold is enfeebled or lost. In some cases, severe pains occur. A spastic condition may be present in the lower extremities. The sphincters are often involved. Trophic changes are common. There may be cutaneous eruptions, as eczema or herpes. The skin may be thin and glossy or thick and horny. Vaso-motor disturbance may be manifested by coldness and lividity.

From what conditions is syringomyelia to be differentiated?

Myelitis, hypertrophic pachymeningitis and progressive muscular atrophy occasion certain symptoms in common with syringomyelia.

Myelitis is recognized by the much more profound palsy and loss of sensory power, without involvement of the pain-sense and the temperature-sense; hypertrophic pachymeningitis by the attendant pain and the less extensive anesthesia; and chronic muscular atrophy by the absence of conspicuous sensory symptoms.

Morvan's Disease-Analgesic Panaris.

What are the symptoms of Morvan's disease?

Under the name of Morvan's disease has been described a syndrome of symptoms, including the development of a painless inflammation at the extremities of the fingers, followed by necrotic sequestration of the phalanges. At the beginning of

the disease, the affected parts may be the seat of pain. Subsequently, analgesia develops together with the destructive process

FIG. 49.

Appearance of the hand in Morvan's Disease. (After Charcot.)

in the fingers. In most cases abnormal curvature of the spinal column has been observed. After death, hyperplasia of the connective tissue of the peripheral nerves and in the posterior horns, posterior columns, and the gray matter of the cervical segment of the spinal cord has been found.

What is the distinction between Morvan's disease and scleroderma?

Scleroderma is a morbid condition in which, as a result of inflammatory changes in the subcutaneous arteries of a varying