teriorly, will give the stature of the body. If the equilibrium is at all changed, this measurement will at once show the extent, which may not be perceptible in the spinal column; if the curve be the result of spinal disease, there will be a corresponding depression of the shoulder on the opposite side of the arc. But if this curve be due to a shortened limb or a diseased hip-joint, the shoulder will not be depressed, but will remain in the natural position as in compensatory curvature of the spine. mensuration from the crest of the ilii to the sterno-clavicular articulation exhibits any departure from the horizontal position of the pelvis due to curvature in the lower portion of the spine or to mal-adaptation of the lower extremities.

Also

I have only recently made these observations and present them for further investigation, hoping the profession will interest themselves in the idea advanced. It will greatly facilitate the diagnosis and prognosis in the examination and treatment of spinal disease. The advantages it possesses over others, in construction, adjustability, and symmetry, are worthy of repetition.

In construction it is light, perforated, strong, durable, simple, and of small cost. In adjustability, being eyeleted as a corset, it is removable without destruction, allows alteration for ease to deformity, yet capable of giving constant support, besides permitting the body to be cleansed and reclothed. It does not destroy symmetry, having been worn unobserved.

THE DEVELOPMENT OF THE OSSEOUS CALLUS IN FRACTURES OF THE BONES OF MAN AND ANIMALS.

BY HENRY O. MARCY, M.D.,

MASSACHUSETTS.

THE results of the investigations which I have the honor to present to you, upon the repair processes in fractures of the bones of animals and man, are quite different from the teachings which I had received, or my previous accepted conclusions.

My studies in this direction were prompted by my clinical observations upon the repair of fractures under various modes of treatment, and especially from my belief, that after careful adaptation and complete rest secured with plastic splints, there occurred, under favorable circumstances, a primary union in bone not unlike that taking place in the repair of superficial wounds.

In one or two monographs upon the treatment of fractures, published some years since, I inculcated this thought. I have availed myself of the great profit derived from the teachings of Comparative Pathology, and have selected the rabbit as the most convenient animal from which to make decalcified injected specimens. First of all, I would give full share of credit to my friend and co laborer, Dr. A. F. Holt, of Cambridge, whose painstaking and carefully prepared microscopic sections will be appreciated by all engaged in this difficult field of histologi

cal research.

A most interesting chapter in the history of medicine would be furnished in giving the different views held in relation to the repair of bones, did the occasion permit. From the time of Galen, the fathers accepted his teaching that "the gelatinous moisture," as he called it, which surrounds the fractured extremities of a bone was the material that formed the new osseous growth called callus. Dupuytren, enlarging upon the doctrines

taught by Galen and Haller, asserted that "nature never accomplished the immediate union of a fracture save by the formation of two successive deposits of callus, one of which is derived from the periosteum, adjacent tissues and the medulla, while the other, formed perhaps from the broken extremities of the bone itself, is found at a later period directly interposed between their surfaces." After the publications of Ollier, in 1859 and 1860, upon the osteo-genetic property of the periosteum, surgeons and anatomists were agreed in rejecting the doctrines taught concerning the formation of the callus, and maintained that the neo-formative process was due wholly to the periosteum. These were the teachings received during my pupilage.

One of Italy's most distinguished students, Prof. G. B. Ercolani, of Bologna, published in 1866 a monograph upon the repair of fractures, and gave as his conclusion that the extremities of a fractured bone took no part in the process resulting from which the osseous callus is formed, and that the periosteum near the fracture is a less important factor than is usually believed, oftentimes undergoing even a destructive process.

In 1867 Billroth, in his important investigations upon the regeneration of bones in fractures,' closed with the following conclusions: "If we now view the processes as a whole, we see that the cell infiltration in the bone itself as well as in all the surrounding parts aids in the formation of callus, and that hence the periosteum plays no exclusive osteo-plastic role." This might have been concluded a priori, for if the periosteum alone formed the external callus, as was supposed, the portions of bone free of periosteum, as those places where tendons are attached to the bone, could form no callus, which is directly contradicted by observations. In normal growths also the periosteum does not by any means have the importance ascribed to it in the formation of bone, for we may just as correctly regard the layer of young cells lying on the surface of the bone and extending into the Haversian canals as belonging to the bone as to refer it to the periosteum. This distinguished surgeon arrived at these conclusions after much careful study upon dogs and rabbits.

From the most remote antiquity it has been known to surgeons, that all about the place where a fracture of a long bone has occurred, there is observed in a few days a material of a

1 Surgical Pathology, American edition, p. 181.

gelatinous appearance mingled with a greater or less quantity of blood. This is elastic, becomes more firm, is smooth externally, and every where embraces the fragments. This is the so-called soft callus, and is destined to be changed into osseous substance. These neo-formative processes have been the subject of careful study by many investigators from Galen to our own day. Differences of opinion have been held as to the origin of the neoplasm and the elements which share most actively in the new growth. Some have believed that it is derived from the blood and its coagulated elements. Others regard it as elaborated from the medulla of the bones. More recently the periosteum alone has been held as the active factor of reproduction. Again, after Billroth, these changes have been assigned to the bone itself.

"This new material," he says, "is developed from the connective tissue of the medullary cavity of the canals of Havers, which proceeds from the surface of the fracture, meets the like tissue which comes from the other fragments, and is blended with it in the same way that the union of the soft parts is effected." This would be analogous to primary union in superficial wounds. Influenced by his own researches in Comparative Pathology, Prof. Ercolani claimed, in 1867, that the periosteum was destroyed in the place where the soft callus was formed, and as a consequent, it could take no active part in the formative pro

cesses.

This was in a measure confirmed by Billroth, and both are now agreed that it is to a new periosteum, formed upon the soft callus from a thick layer of connective tissue, to which must be ascribed a very important function.

If there was error in Ollier's theory, which made the formation of the callus depend upon that portion of the periosteum which is destroyed and absorbed, Billroth's teaching is also incomplete, when, to the new-formed periosteum, he would attribute the development of the osseous substance of the callus, since this is the result of two equally indispensable conditions, namely, periosteum or ossifying organ upon the one side, and ossiferous organic elements upon the other. Therefore, as the irritated periosteum finds in the exudation from its own vessels the ossiferous elements, so the new periosteum, which is under discussion, finds in the soft neoplasm ossiferous elements, without which the new-formed periosteum, like the old periosteum

in sound bones, though it repairs the waste of the bone, is yet inadequate to the reproduction of new osseous substance.

Ercolani says, "that comparative researches, moreover, will show, not only that the new doctrine taught by Billroth on the formative process of the callus is erroneous, but also that no single principle is sufficient to explain the formation of the callus in the different cases of fracture."

This would naturally differ, not only in the long and the flat bones, but according as fractures of the long bones are simple or compound, and also in simple fractures, whether the fragments are maintained close together or apart from each other during the period in which the callus is formed.

Before proceeding to study in detail the importance of the several elements or tissues existing at the place where a fracture may occur, it is necessary to refer briefly to the normal development of bone, for it would seem a fair deduction to suppose that the repair processes in a fracture do not very widely depart from those of formation. Examine the growing bone of a very young child. The condyles are composed of cartilage, and the periosteum is continued from the shaft of the bone over the cartilage, the outer layers of which have assumed a fibroid character. This is the way in which the periosteum is formed, and it may be considered a fibro-cartilage developed out of the temporary cartilage, from which the shaft of the bone is produced. This newly formed fibro-cellular tissue, covering the developing bone, contains living cells of precisely the same nature as those from which the shaft is constructed, and, in this manner, the circumference of a long bone is increased, as layer upon layer of the cells ossify, arranging themselves into Haversian systems.

This vitalized matter, the germinal material of Beale, under favorable circumstances, surrounds itself with a soft hyaline substance, which, as it increases in quantity, separates the nuclei of the original cells from one another, and about the nucleus there is secreted into the hyaline material lime salts, and, so to speak, each cell becomes encased in a shell firmly fixed to its neighbor, and thus the so called osteo-blasts become bone corpuscles.

This is the end of the development series, the highest possible form of osseous growth, and the integrity of its vitalized conditions is maintained by the nutritive supply furnished through the Haversian and canalicular circulation.