Limb (anatomy)

“ The musculo-spiral nerve, g, winds under the brachial artery at the middle of the arm, but as this nerve passes deep between the short and long heads of the triceps muscle, P, and behind the humerus to gain the outer aspect of the limb, a little care will suffice for avoiding the inclusion of it in the ligature. ”

“ The segments are flattened, and since the greatest strength when used in pushing and crawling is in the long axis of the oval section of the flattened limb, it seems probable that these limbs did not hang directly down, with their sides vertical, but that their position in life was very much the same as that in which they are preserved as fossils. By moving these bowed legs forward and backward in a plane at a small angle to the surface of the body, a powerful pushing impetus could be obtained. ”

“ Whenever a tight ligature applied to a limb makes the lower part swell, whenever too long standing, a perpendicular position of the superior extremities, &c. produce the same effect, it is to be presumed that the effusion depends upon the compression of the lymphatics, and takes place then like venous dilatations in similar circumstances, because the lymph finds it difficult to circulate. ”

“ There is here no essential modification in the anatomical relations of the various parts of the limb, and it is inconceivable that any such subsequent development should be connected with this form of climbing organ as is presented in the limbs of the anthropoid apes and man.
In the plantigrade animal, on the other hand, the disposition of the limb is such that when the weight of the body is thrown upon it the toes tend to be thrust apart even when the foot is resting on a flat surface, and to be forced into a concave shape when pressed upon a rounded object. ”

“ To illustrate, we will take the lower limb, whether there is lameness, soreness, gouty, rheumatic, neuralgic, swollen, shrunken, feverish, cold, smooth and glassy, sores, ulcers, erysipelas, milkleg, varicose veins, or any defect that the patient may complain of, who is the only reliable book or being of symptomatology. For convenience we will divide that lower limb into five parts, the foot, leg, thigh, pelvis and lumbar region. The patient (symptomatologist) tells us he has a pain in front, center and under part of foot. ”

“ If an examination is made when the patient is thus halting, and even though he complains of no pain, the limb is found shrunk, wasted, and lengthened. The elongation of the limb occurs mainly in consequence of the inclination of the pelvis towards that side. When the disease has made progress, it has been supposed that swelling of the apparatus of the joint, and effusion into its cavity, might separate the head of the bone from the acetabulum, when pressure from the trunk was not applied. ”

“ If no means are taken to replace the bone, and painful feelings subside along with the swelling, the limb remains long useless, and is the seat of occasional lancinating pains, but at last motion and utility are to a certain extent restored by the formation of a new joint—the head of the bone, and the parts on which it rests, mutually accommodating themselves to each other, by degrees, and permitting a limited extent of motion. ”

“ This may soon be absorbed and with it the articular ends of the bones wear away and break down into small fragments. The limb becomes atrophied and shrunken, and the joint itself becomes weak, often flail. ”

“ The other bones of the human body sometimes undergo subluxation, and sometimes complete luxation, but the articulations at the hip and the shoulder are subject only to complete luxation, more especially the hip-joint, because it has a deep and round cavity which is further strengthened by a strong brim. The limb, then, being subject to displacement from its cavity by some great violence, many differences arise according to the greater or less degree of the dislocation. ”

“ To establish the part they play in our geometrizing, it is necessary to review a few facts. It has long been known by medical practitioners that, in patients with cutaneous anæsthesia of a limb, whose muscles also are insensible to the thrill of the faradic current, a very accurate sense of the way in which the limb may be flexed or extended by the hand of another may be preserved. ”

“ Neither does the limb at the groin admit of flexion as in the sound limb, and the head of the bone is felt at the perineum too prominent. These, then, are the symptoms attending dislocation of the thigh inward. ”

“ The limb is often enormously swollen and indurated. The gelatinous effusion beneath the periosteum speedily becomes organised, nodules of osseous matter project into it, and adhere to the surface of the bone frequently by a narrow neck; these increase in number, gradually assume a solid appearance: the bone is thus thickened, often to a very great extent. ”

“ Tenderness is elicited on making pressure over the joint, on pressing together the iliac bones, or on attempting to abduct the limb while the pelvis is fixed. The muscles of the buttock and thigh are wasted. As any attempt to bear weight on the affected limb causes pain, the patient walks with a limp, and to save the joint he assumes an attitude which is characteristic: he throws his weight on the sound limb, leans forward, using a stick for support, tilts the affected side of the pelvis downwards, and flexes the hip and knee-joints of the diseased limb. ”

“ When, then, the articular extremity of the femur has worn out a socket for itself in the flesh where it was lodged, and the flesh is lubricated, it ceases to be painful in the course of time, and when it becomes free from pain, they can walk without a staff, if so inclined, and they can support the body on the injured limb. ”

“ Those at the knee, for example, contribute more to the length of limb than do those at the hip or ankle, and they are also the last to unite. In the upper limb the more active epiphyses are at the shoulder and wrist, and these also are the last to unite. ”

“ Part XXIII The symptoms of dislocation backward are:-The parts before more empty, behind they protrude, the foot straight, flexion impossible, except with pain, extension least of all: in these the limb is shortened. They can neither extend the limb at the ham, nor at the groin, unless it be much raised, nor can they bend it. The uppermost joint, in most cases, takes the lead: this is common in joints, nerves, muscles, intestines, uteri, and other parts. ”

“ The upper limb in man may be subdivided into a proximal part or shoulder, a distal part or hand, and an intermediate shaft, which consists of an upper arm or brachium, and a forearm or ante-brachium. In each of these subdivisions certain bones are found : in the shoulder, the clavicle and scapula ; upper arm, the humerus; in the forearm, the radius and ulna, the bone of the upper arm in man being longer than the bones
of the forearm ; in the hand, the car- pal and metacar- pal bones and the phalanges. ”

“ After the amputation, of a foot or a finger, it has frequently happened, that an injury being offered to the stump of the amputated limb, whether from cold air, too great pressure, or other accidents, the patient has complained, of a sensation of pain in the foot or finger, that was cut off. Does not this evince that all our ideas are excited in the brain, and not in the organs of sense? ”

“ As therefore the union of the nerve with the brain is indispensably necessary for the purpose or act of perception, we are naturally led to inquire into the properties of this substance, termed the brain. Before we proceed to this part of the subject, it will be proper to notice a fact which is of frequent occurrence. In amputations of the thigh, [Pg 12] at the moment the femoral nerve is divided, it often occurs that a pain is distinctly felt in the toes; and after the limb has been removed, even for many months, the same painful feeling of these lost extremities is occasionally experienced. ”

“ The unnatural bulk of the limb is afterwards much diminished, for the new bone gradually becomes consolidated, and smooth on the surface by the action of the absorbents. Nature seems to construct her107 substitute after the model of the original, and in some instances but very little change can afterwards be observed in the limb. ”

“ It seems almost impossible to believe that men and women could thus make a limb useless, but this is actually what happens rather frequently. The effects of the original injury will pass off in a few days, but the effects of the disuse of the limb may remain for months or even years because of the disturbance of circulation and of nerve impulse. It is probable that the nerves themselves have a trophic or nutritional—that is, vitalizing—influence upon muscles. ”

“ The limb is adducted, its normal range of abduction, and sometimes also of flexion, is restricted, and there is, as a rule, some degree of lateral rotation, so that the toes point outwards. It should be noted that the same picture—shortening with eversion and stiffness at the hip—results from the common fracture of the neck of the bone in old people. The adduction element of the deformity is partly compensated for by upward tilting of the pelvis on the affected side and curvature of the spine with its concavity towards the affected limb. ”

“ But the injured limb, in this case, can support the body much better than in dislocation inward, both because the head of the femur and the neck of its articular extremity, being naturally oblique, have formed a bed under a considerable portion of the hip, and because the extremity of the foot is not forcibly turned outward, but is nearly in a line with the body, and is even inclined more inwardly. ”

“ After a time, flexion can be made to a right angle; and the limb becomes tolerably useful. By unsuccessful attempts to restore the natural position, inflammation is excited; and thus the salutary processes, commenced by nature for reparation of the displacement, are interrupted and delayed; in young persons such disease of the joint may be produced as might lead to loss of the extremity.
Luxation of the Radius alone, backwards on the outer condyle, is sometimes met with; but this bone is seldom singly displaced far from its original site. ”

“ By the approach of a magnet to a contractured limb the phenomenon may be completely transferred to the corresponding muscles upon the opposite side of the body. If upon a limb of a lethargic patient who has been rendered cataleptic by opening the eyes an Esmarch's band be applied, pressure over the bloodless muscles excites no contracture until the band is removed. ”

“ If any osseous deposit has taken place, it is absorbed; the ends of the bone are diminished in size by interstitial absorption; ligamentous or fibro-cartilaginous tissue is formed round the wasted extremities; and the surrounding cellular tissue being thickened and condensed, a sort of synovial pouch is formed, in which the ends, by this time smooth and rounded off, move freely. The limb is shortened in some degree, and its actions are very much diminished in force, there being no sufficient support for the muscles. ”

“ The muscles also are not much altered in the first instance, except that they deviate from their natural direction, and that, like the ligaments, they are elongated on the one hand and shortened on the other. In ancient cases the whole limb is always considerably wasted, and many of the muscles are remarkably thin and pale, or even transformed into soft, fatty bundles. The cellular substance is condensed and diminished in quantity; the adeps is absorbed; and even the vessels and nerves supplying the affected part are apparently reduced in volume. ”

“ But those who are neglected, and are not in the practice of putting their foot to the ground, but keep the limb up, have the bones more atrophied than those who use the limb; and, at the articulations, the limb is more maimed in the direct line than in the other forms of dislocation.
Part LXI In a word, luxations and subluxations take place in different degrees, being sometimes greater and sometimes less; and those cases in which the bone has slipped or been displaced to a much greater extent, are in general more difficult to rectify than otherwise ”

“ In older persons the bones more readily break than bend. The diagnostic signs of the accident are, pain and deformity at the seat of the injury, loss of power in the limb, want of displacement of fragments, and absence of crepitation. The deformity consists in an unnatural curvature, which can be made to disappear under pressure and extension, but recurs, to a certain extent, when the limb is liberated. When attended with partial fracture, the symptoms are the same, excepting that, instead of a curvature, there is angular deformity opposite the seat of the accident. ”

“ This limb, by the way, has lost its tip, and is being regenerated, the lighter portion, as shown in the figure, having already been grown. I might note that at the point where the injury occurred a small transverse branch later made its appearance, but after this had grown for a year or two and become one eighth of an inch in diameter, it gradually degenerated and finally entirely disappeared. ”

“ For if the accident be recent and the patient young, we may sometimes succeed in reducing the limb by grasping and rotating the thigh this way and that. When the dislocation is inwards we may sometimes accomplish our purpose by bending the limb at the groin inwards frequently and strongly. If the dislocation does not yield to these means we must have recourse to extension, first with the hands, certain assistants grasping the thigh and leg and pulling the limb downwards, while others grasp the body at the armpits and pull upwards. ”

“ Every limb shrinks sensibly in volume from this withdrawal of the blood, and the shrinkage of any one of them, say the right arm, is measured by the fall of water in a gauge that communicates with a long bottleful of water, through the neck of which the arm has been thrust, and in which it is softly but effectually plugged. ”