Aponeurosis

“ The aponeurosis fibres continue in the direction of the muscle-fibres to the
Insertion into the median raphe ventrad of the sternum from the insertion of the seventh costal cartilage to the xiphoid process, into the linea alba from the sternum to the pubic tubercle, and into the tubercle and the cranial border of the pubis. Caudad of the xiphoid process the aponeurosis is closely united to the superficial layer of the internal oblique, where it forms the outer layer of the sheath of the rectus abdominis. Laterad of the pubic tubercle the tendon is perforated by the inguinal canal. ”

“ I have uniformly observed that the serous infiltrations always begin in the sub-cutaneous cellular texture, that it is only in an advanced stage of dropsy, that we find effusion in that which is under the aponeuroses, and that in general it does not contain as much serum in proportion as the other. In most of the great distensions of dropsical limbs, when the skin is removed and the subjacent water has flown off, the limb covered by its aponeurosis, is scarcely larger than in the ordinary state. ”

“ Origin.—Approximately the anterior half attaches by an extensive aponeurosis, which is continuous anteriorly with that of M. extensor iliotibialis anticus, to the anterior iliac crest, ending posteriorly at the anterior end of the lateral iliac process; the posterior part attaches fleshily to the edge of the entire lateral iliac process and (posterior few mm.) aponeurotically to the entire lateral ischiatic ridge. The proximal part of the belly is much thicker than the fleshy origin. Two accessory aponeuroses associate with the anterior part of the muscle ”

“ There is no occasion to dissect and reflect the flap, for the cellular substance connecting the skin with the subjacent aponeurosis is so loose, that it can easily be drawn up above the place where the joint of the calcaneum with the cuboides and that between the astragalus and scaphoides ought to be opened. The surgeon will penetrate the last the most easily, particularly by taking for his guide the eminence which indicates the attachment of the tibialis anticus muscle to the inside of the os naviculare. ”

“ From the last nine or ten ribs by means of as many tendons, which are interconnected to form arches that span the slips of the serratus anterior. The muscle-fibres arise from these tendons and from their intervening arches. (b) From the lumbodorsal aponeurosis common to it and the internal oblique. The cranial fibres pass nearly ventrad, the caudal fibres caudad, and the intervening fibres take an intermediate course. The fibres end in a thin aponeurosis of insertion along a curved line which passes at first caudad and then laterodorsad. ”

“ On the sole of the foot and the palm of the hand, we observe an infinite number of white fibres, shining like aponeurotic fibres, which are detached from this internal surface, form upon it a kind of new layer, cross each other in all directions, leave between them, especially towards the heel many spaces of different sizes, that are filled with fat, separate more and more, and are finally lost in the sub-cutaneous texture, nearly as the fibres of the brachial aponeurosis insensibly disappear in the neighbouring cellular texture. ”

“ This can only be done by removing the horny sole and frog, and cutting boldly down upon the structures beneath. The operation is known as resection of the plantar aponeurosis, or the complete operation for gathered nail.
Practised for some years on the Continent, this operation, on account of its gravity, has been avoided by English veterinarians. From reported cases, however, it appears often to be followed by success. ”

“ These parts are all covered in by the aponeurosis,—which fixes itself to the base of the jaw,—and by the platysma and superficial fascia,—which continue themselves on the face. They are readily accessible to the surgeon, but seldom subjected to any operation of importance. The deep or sublingual portion of the digastric space has its roof formed by the mucous membrane, which, between the tongue and alveolar arch, constitutes the floor of the mouth: the side of the tongue and the continuous surface of the pharynx, as already described, compose its inner wall ”

“ Sometimes the posterior primary division of the third cervical nerve reaches the scalp still nearer the middle line behind.
The third layer of the scalp or epicranium is formed by the two fleshy bellies of the occipito-frontal is muscle and the fattened tendon or aponeurosis between them. Of these two bellies the anterior (frontalis) is the larger, and, when it acts, throws the skin of the forehead into those transverse puckers which are characteristic of a puzzled frame of mind. ”

“ In the integument, a small localised abscess, attended with pain and œdema of surrounding parts, may form. Pus forming under the aponeurosis is liable to spread widely, pointing above the eyebrow, in the occipital region, or in the line of the zygoma. Suppuration under the pericranium tends to be limited by the inter-sutural attachments of the membrane. Necrosis of the outer table, or even of the whole thickness of the skull, may follow, although it is by no means uncommon for large denuded areas of bone to retain their vitality. ”

“ If from the examination of the fleshy mass, we pass to that of the separate fibres that compose it, we see that the length of the first is rarely the same as that of the second. There are hardly any but the sartorius and some analogous muscles, whose fibres run the whole extent of the fleshy, mass; in almost all the others, they are found obliquely arranged between two aponeuroses, or between a tendon and an aponeurosis; so that though each of them334 may be very short, as a whole they are very long, as we observe in the anterior rectus of the thigh, the semi-membranosus, &c. ”

“ Operation.—A line drawn from the centre of the space between the tuberosity of the ischium or the great trochanter to a corresponding point between the condyles of the femur will give the direction. A free incision in this line three or four inches in length—the nerve lies just below the the femoral aponeurosis, beneath the edge of gluteal fold, requiring no muscular fibres to be divided. It must be raised from its bed and boldly stretched or elongated into a loop. Symington's experiments have shown that in the average adult 130 lb. are required to break the nerve. ”

“ According to Cruzel, fixation of the biceps femoris may occur, in very thin animals, without rupture of the musculo-aponeurotic layer, the process being then simply confined to stretching of the aponeurotic layer over the summit of the trochanter. Under such circumstances the musculo-aponeurotic layer presents a cup-like depression, into which the summit of the trochanter fits, and thus effectually prevents movement of the muscle.
Whether the accident is due to an actual fissure, or only to stretching of the aponeurosis, the symptoms are the same. ”

“ The contractility of texture is accommodated in the fibrous system, to the degree of its extensibility; as it cannot suddenly be distended, it cannot suddenly contract when it ceases to be distended. This fact is remarkable in the division of a tendon, of a portion of aponeurosis,274 of a ligament laid bare in a living animal, in an incision of the dura-mater, to discharge blood effused under it, &c. ”

“ Where the four digital bands diverge they are joined together by deep transverse fibres which pass from the inner to the outer border of the hand, blending in these situations with the muscular aponeurosis. ”

“ To a philosopher such questions as this must arise: Has the appendix at its entrance a sphincter muscle similar in action to that of the rectum and œsophagus? Has it the power to contract and dilate?—contract and shorten in its length and eject all substances when the nerves are in a normal condition? And where is the nerve that failed to execute the expulsion of any substance that may enter the cavity of the appendix? Has God been so forgetful as to leave the appendix in such condition as to receive foreign bodies without preparing it by contraction or otherwise to throw out such substances? ”

“ These aponeuroses are met with in insulated parts, in front of the abdomen, on the head, the back, &c.; they are usually destined to retain in place a certain number of muscles which they do not surround on all sides, like the preceding, but with which they correspond only in one direction. Their thickness is much less than that of the preceding ones; it is adapted to the efforts that they are to support. ”

“ After _division at the wrist_, the abductor-opponens group of muscles and the two lateral lumbricals only are affected; the abduction of the thumb can be feebly imitated by the short extensor and the long abductor (ext. ossis metacarpi pollicis) , while opposition may be simulated by contraction of the long flexor and the short abductor of the thumb; the paralysis of the two medial lumbricals produces no symptoms that can be recognised. It is important to remember that when the median nerve is divided at the wrist, deep touch can be appreciated over the whole of the area supplied by the nerve ”

“ The orbicularis oculi muscle, which is principally supplied by the portio-dura nerve, is paralyzed, though it still retains a partial power of contraction, owing to the anatomical fact that some terminal twigs of the third or motor pair of nerves of the orbit branch into this muscle.
The facial artery, V, and the facial vein, U, Plate 4, are in close connexion with the submaxillary gland. Oftentimes they traverse the substance of it. The lingual nerve and artery lie in some part of their course immediately beneath the gland. ”

“ For this reason, the muscles are called the active, and the bones the passive, organs of motion. By carefully examining a muscle it will be found to consist of actual, minute, reddish, muscular fibres. As a rule, muscles terminate in more or less strong, glistening, fibrous cords called tendons, or fibrous sheets termed aponeuroses, by which they are attached to the bones. In the limbs are muscles terminating in very long tendons, which act as draw-lines upon the distant bones of the foot (long and short pasterns and pedal bone) and set them in motion. ”

“ The pyramidal tract conveys impulses that inhibit muscle tonus, while the rubro-spinal tract is the path by which excitatory impulses travel. When the inhibitory influences are cut off, as in a lesion of the internal capsule, the paralysed muscles become spastic, and the deep reflexes are exaggerated. When the excitatory impulses are also lost, as in a total transverse lesion of the cord, the paralysed muscles are flaccid and the deep reflexes disappear. In destructive lesions of the lower neurones, the muscles are always flaccid. ”

“ Several previous workers have reported some dorsal muscles supplied by ventral nerves and vice versa. Those findings should be viewed with suspicion until verified, because the proximal parts of the tibial and peroneal nerves are intimately associated and their relationship is easily misinterpreted. I found a branch of the tibial nerve that is closely associated with, and distributed with, the peroneal nerve. That branch of the tibial nerve has been mistakenly considered a part of the peroneal nerve by some workers. My study revealed no definite exceptions to the expected innervation. ”

“ The nerve-trunks uniting the bodies with the spinal nerves are (at least in specimens hardened in picric and chromic acids) very difficult to see, and I have failed to detect that they are connected with special parts of the bodies, or that the separate alveoli differ much as to the nature of their constituent cells. The aortic branches to the bodies are larger than in the previous stage, and the bodies themselves fairly vascular.
By stage Q (Pl. 19, fig. 9) two distinct varieties of cells are present in these bodies. ”

“ So much is certain, that in that region, where arteries and veins are not to be seen, there are also no separate nerve twigs, and that here the union or coalescence of nerve and tissue which the nerves are to influence must have taken place. If one considers the fine meshes of the capillary network enveloping the ducts, and keeps in mind the abundance of nuclei belonging to the capillary, the membrana propria and the duct cells proper, he can imagine how difficult it must be to follow the course of the nerves through and among all these structures. ”