the blood-vessels regain their normal size, the inflammatory effusion clears up, and the integuments become looser, and slide more easily.

66

With the increase of toughness, the new substance acquires a more decidedly filamentous appearance and structure. After the fourth day, the microscope detects nuclei in the previously homogeneous, fibrine-like reparative material; and after the seventh or eighth day, there appear well-marked filaments, like those of the less perfect forms of fibrous tissue. Gradually perfecting itself, but with a rate of progress which becomes gradually less, the new tissue may become at last, in all appearance, identical with that of the original tendon." 1

In the experiments which I made to determine some points of Mr. Paget's description on which doubt had been cast, I endeavoured to divide the tendons in the same manner as in man, and afterwards to keep the limb at rest, and the articulation motionless; for it appeared to me, that to divide the tendons of animals, allowing the animal subsequently to move the limb at will, and to draw conclusions from the results obtained, and compare them with what occurs in man, when the limb is kept at perfect rest by means of splints and bandages until reunion is effected, would be to deceive one's self.

I found, on dividing the tendo Achillis in a rabbit, that the ends of the tendon were immediately separated to the distance of one inch; that is to say, that the upper extremity was drawn away by the muscles retracting to that extent. On the second day, a small and unimportant film of blood was found in the sheath of the tendon, and a small quantity of lymph was attached to the upper end of the tendon. On the third day, the space between the ends of the tendon was three fourths of an inch, the sheath was

'Lectures on Surgical Pathology,' p. 270, vol. i, 1853.

thickened and its vessels injected; soft lymph was attached to both extremities of the tendon, especially to the upper; and on the fourth day this constituted a soft bond of union. On the sixth day, the ends of the tendon were half an inch apart, and the intermediate space was filled by a firm, welldefined substance, streaked with blood, and distinctly fibrous. The ends of the tendon, especially the upper, were enveloped by this new material, to the extent of a quarter of an inch; they were also somewhat swollen, softened, and succulent. In some few instances an elongated clot of blood was embedded in the new material, apparently as an accidental product it did not appreciably hinder the healing process. The new substance was well defined, and had already acquired considerable strength. On the seventh day, Mr. Paget found, in his experiments, that the half section of the connecting band would bear gradually increased suspended weights to the amount of ten pounds. On the eleventh day, the intermediate substance had contracted to a quarter of an inch in length, and was only slightly adherent to the cellular sheath; it was softer, paler, and thicker than the normal tendon, but not less well defined. It was capable of very considerable resistance. Mr. Paget found that, at this time, the half section was capable of bearing suspended weights to the amount of fifty pounds: it was broken with fifty-six pounds.

Occasionally, the tendon is streaked with blood, as is seen on making a longitudinal section. The reparative process apparently proceeds equally well, whether the sheath be entirely or in part only divided, yet the sheath is doubtless important in giving definition to the new product. In the above-mentioned experiments slight adhesion to the sheath generally existed; but in many instances the tendon

was perfectly free in its sheath.

When it was entirely

divided, the sheath did not contract with the muscle.

Each day added to the strength and perfection of the intermediate substance: also, its length gradually diminished, until a slight bulbous enlargement of the tendon alone marked the point of division. At the end of the tenth week, or from that time to the third month, this enlargement had disappeared, and the point of union was only appreciable on making a longitudinal section of the tendon: a very small cupped depression marked the point of division of the tendon.

These examinations were continued from day to day for three months, and they tend to confirm the opinion entertained by Mr. Tamplin and others, of the gradual contraction of the new uniting bond, until a cicatrix alone remains ; which, also, is subsequently removed, and is not to be traced even by microscopic aid.1

1 Whilst these pages are passing through the press, I perceive a paper by Mr. W. Adams ('Med. Times and Gazette,') on the subject of the division of tendons. Mr. Adams differs from former experimenters, and states that the space between the divided extremities of the tendon increases from one to two and a half inches. Now this is entirely at variance with what is known to occur both in man and animals, when the limb is kept at rest, and in a position to favour reunion. But in the experiments undertaken by Mr. Adams, and for which rabbits were chosen, after division of the tendon, the animal was allowed to move about, without any protection to prevent motion of the limb. Union was effected, but the uniting medium was stretched and rendered weak. Also in man the same occurs, when extension of the soft material is effected too rapidly. Not unfrequently, in animals, re-union does not take place, if the ends of the tendon are not in some measure approximated; but the ends of the tendon are gradually more widely separated until the intervening space may be several inches in length, the lower portion of the limb being drawn downwards by the action of the antagonistic muscles. I have known this to occur in a dog: the intervening space became half a foot in length.

That the uniting medium may be drawn out even to a greater extent than two and a half inches, is well understood; and in orthopaedic surgery this is a most important circumstance, allowing as it does of the restoration of a limb to its

When the muscle has undergone structural shortening, so that division of its tendon cannot produce the desired relaxation or lengthening of the muscle itself, the new bond of connection may be extended to supply the deficiency occasioned by the abnormal condition of the muscle. It may be drawn out by gradual extension to the length of three inches, and upwards, beyond its normal length. This is a point of great importance in the treatment of old distortions, and those occasioned by injury and inflammation of muscle. When, however, extension to a similar extent is made, the muscles being healthy, the result is to occasion such an amount of debility as to render the limb comparatively useless. For instance, if the Achilles tendon be divided, the muscle being healthy, as is usual in infantile congenital varus, the muscle becomes relaxed, in consequence of the section; not immediately, however, but gradually and permanently, until solid reunion has taken place. But, if the new material is at the same time rapidly elongated to the length of three inches, debility, amounting to paralysis, is induced; and instead of equinus, a condition resembling calcaneus, or indeed calcaneus, will result.

Thus, I have endeavoured to show, that two distinct classes of cases exist requiring the division of tendons; namely, that in which the muscle is healthy but retracted; and secondly, that in which it has undergone structural change.

normal position after structural change in the muscles has taken place, and after the formation of adhesions. I make these remarks with regard to the experiments instituted by my friend and colleague, Mr. Adams, for it appears to me that they were not made with his usual acuteness of observation, and are calculated to mislead those who are less versed in the subject than himself.

CHAPTER VI.

TREATMENT.

THE treatment of talipes resolves itself into; first, the removal of distortion and restoration to the normal position of the limb; and, secondly, the restoration of function.

Removal of distortion may be effected by mechanical means alone; or by surgical and mechanical means combined. The former mode of treatment yields with advantage to the latter; yet, in a large number of cases undoubted success attends the employment of long-continued mechanical

means.

Formerly, the most exaggerated notions prevailed, and the greatest dread was expressed, respecting the division of tendons. Thus, it was thought worthy of record, by Desport, that a patient in the Hôtel Dieu, in Paris, in whom the tendo Achillis had been divided, had recovered without amputation of the leg. And so late as the year 1835, we find Dr. Ryan thus expressing himself:

"Some have supposed that the deformity (pes equinus) was caused by a rigidity and shortening of the extensor muscles; to remedy which, Delpech proposed to incise the tendo Achillis. It appears to me," continues Dr. Ryan, "that this operation would only be justifiable when all other means had failed; and even then I very much doubt its propriety."

1

Lectures on the Physical Education and Diseases of Children, London Medical and Surgical Journal,' p. 234, vol. vii.