Leg (anatomy)

“ The wasting of these muscles is of little importance to us who have no need to use our toes in detail; but it is far otherwise with the deep flexors of the foot and toes which are attached to the leg-bones, and whose tendons pass under the ankle joint and arch of the foot and form their chief support. It is, indeed, from the wasting or inaction of the deep flexor muscles, coupled with the turning out of the toes which fashion has imposed upon us, that the ankle and arch of the foot give way under the changed position of the limbs in girls at puberty, which I have described ”

“ On the other hand, the femur is united, as with us, to a massive pelvis; the articular surfaces of the knee, the knee-pan, and the two immovable bones of the leg, are just what the exclusive function of locomotion requires; the foot is plantigrade, with a prominent heel and close toes, and is articulated perpendicularly by its arch with the leg, as in man. ”

“ There may be a feeling of weight in the limb, and in the case of the knee and ankle the patient tires on walking and drags the leg with more or less of a limp. Movements of the joint are permitted, but are limited in range. ”

“ The foot being fixed in the equinus position the patient must wear boots while the examination is being carried out.
B. Mechanism of walking.—In walking, a step being taken with the artificial leg, the toe of the foot is the last to leave the ground, the heel being raised and the knee straight. The limb is swung forward and raised by flexion of the hip: active flexion of the knee is impossible, but passive flexion occurs, owing to the weight of the leg piece, as the thigh is raised. ”

“ Stimulation of the skin of the hind foot by any of various stimuli that have the character of threatening the part with damage causes the leg to be flexed, drawing the foot up by steady maintained contraction of the flexors of the ankle, knee and hip. In this reaction the reflex arc is (under schematic provisions similar to those mentioned in regard to the scratch reflex schema) (i.) the receptive neurone, noci-ceptive, from the foot to the spinal segment, (ii.) the motor neurone to the flexor muscle, e.g. of hip (a short intra-spinal neurone) ”

“ Almost always when the will is exerted to move the toes, actual contraction may be perceived in the muscles of the stump. One might, therefore, expect that where the toe-moving muscles were cut off, the sense of the toes being moved might disappear. But this is not the case. I have cases of thigh amputation, in which all the foot-moving muscles are gone, and yet in which the feet or toes seem to move at will. And I have cases of lower-leg amputation in which, though the foot-moving muscles contract in the stump, the toes or feet feel motionless. ”

“ Whereas on the left side plantar stimulation produced not only the normal flexor reflex but also the classical defense movements of flexion of leg on thigh and thigh on hip,—on the right side neither a needle nor a match, nor any other form of stimulation of the sole, produced any kind of reaction on the part of the toes, the fascia lata, or any leg muscles. ”

“ But yet they can bend the limb, unless prevented by pain, and the leg and foot appear pretty straight, and not much inclined toward either side, but at the groin the flesh, when felt, appears looser, from the bone of the joint having slipped to the other side, but at the nates the head of the femur may be felt to be more prominent than natural. Such are the symptoms accompanying dislocation of the thigh backward. ”

“ The chief elastic distributing springs are the mass of muscles on the front of the thigh and that on the front of the leg. These deaden the shock much as two great India-rubber bands. The ankle and hip joints help but little, while the curves of the spine and the disks of cartilage between the vertebrae aid a great deal in lessening the impact of the body with the ground. ”

“ The bones of the column meet and form articulations that are held together by ligaments, and attached to their faces, borders and extremities are muscles and tendons. In the superior portion of the limb the muscles are heavy, tapering inferiorly, and terminating in the region of the foot in long tendons. Each limb is divided into four regions. The regions of the fore-limb are the shoulder, arm, forearm and forefoot. In the hind limb are the regions of the pelvis, haunch, thigh, leg and hind-foot. ”

“ The same observation may be made with regard to the pelvis, basin, or lowest part of the trunk, which by its conformation would bend upon the thighs, if not kept back by the great mass of muscular fibres that form the hips. In front of the thighs, again, are the muscles which, by keeping the kneepan in position, are the means of preventing the leg from bending. Lastly, the muscles forming the calves, by contracting, are the means of preventing the leg from bending upon the foot. ”

“ Attached, on the one hand, to the pelvis, and on the other to this fragment, to the rotula, the tibiæ, and the fibula, these muscles have on the former their fixed, and on the latter their moveable points, and, drawing the leg, the knee, and the inferior portion of the thigh upward, they produce the displacement and shortening either mediately or immediately. In this displacement, the adductores, the semi-tendinosus, the semi-membranosus, the rectus anterior, the rectus internus, &c. are the principal agents. ”

“ Innervation.—A branch of the medial division of the tibial nerve penetrates the medial surface of the posterior head.
Individual Variation.—In half the legs, the proximal end of the lateral head is notched for the passage of the peroneal nerve; the main part of the head lies medial to this nerve; the short fleshy slip lateral to this nerve arises by a long, slender, and extremely weak tendon from connective tissue surrounding the femorotibiotarsal joint. In one leg, a bundle of fibers separates from the lateral head and attaches to the terminal four mm. ”

“ At first the limbs are of almost no use in locomotion, but the fundamental trunk muscles with those that move the large joints are more or less spasmodically active. Then comes creeping, with use of the hip muscles, while all below the knee is useless, as also are the fingers. Slowly the leg and foot are degraded to locomotion, slowly the great toe becomes more limited in its action, the thumb increases in flexibility and strength of opposition, and the fingers grow more mobile and controllable. ”

“ Let us now come, at last, to the mechanical structure of bone, of which we find a well-known and classical illustration in the various bones of the human leg. In the case of the tibia, the bone is somewhat widened out above, and its hollow shaft is capped by an almost flattened roof, on which the weight of the body directly rest. ”

“ The gluteal, posterior femoral, gastrocnemial, and outer pedal surfaces are affected together with the muscles moving the foot, while the thigh and inner side of the leg and foot become anæsthetic, with lesion of the upper part of the lumbar enlargement accompanying paralysis of the quadriceps and deep muscles. ”

“ In the simplest form of apparatus locomotion is expected to be accomplished by the action of muscles inserted above the seat of the paralysis. Thus, when the muscles passing over the ankle-joint are paralyzed, the foot is moved as a dead weight by means of the quadriceps extensor, popliteus, and hamstring muscles inserted at the upper extremity of the leg. ”

“ The tibialis anticus and muscles of the outer side of the leg are operated upon by rolling them under the finger-tips and by pressing with the thumb while firmly pushing upward from the ankle to the knee. ”

“ Insertion.—The attachment is by a short flat tendon to the lateral surface of the femur distal to the trochanter and anterodistal to the insertion of M. piriformis and deep to the proximal part of M. vastus lateralis pars lateralis.
Innervation.—The dorsal division of the femoral nerve penetrates the ventral surface.
Individual Variation.—The dorsal division of the femoral nerve may fuse proximally with either the anterior or middle division. In one leg, there are two separate branches to the muscle. ”

“ SECTION III. LAMENESS IN THE FORE LEG. Anatomo-Physiological Review of parts of the Fore Leg.
For supporting weight, whether the subject is at rest or in motion, the bony column of the leg, together with attached ligaments, tendons and muscles, is wonderfully well adapted by nature for the function which they perform. The several bones which go to make up the supportive portion of the leg, are so joined at their points of articulation, that a minimum degree of strain is put upon each attachment. ”

“ From exercise, then, the fleshy parts on the hand and fore-arm are not atrophied in weasel-armed persons, and by these means the arm, too, gains flesh. But in dislocation inward at the hip-joint, whether from birth or from childhood, the fleshy parts, on that account, are much more atrophied than those of the hand, because the patients cannot exercise the leg. ”

“ As the weight of the body is imposed upon the artificial leg, under a high pressure, changing from naught to the entire weight of the body, and at times to double that weight or more, the least particle of chafing or friction would soon cause soreness and might continue to that extent that the limb would be impossible of good, and, moreover, a source of much injury to the wearer. ”

“ The large or apparently Sweled legs particularly observable in the women, are obtained in a great measure by tying a cord tight around the leg above the ancle bone. their method of Squating or resting themselves on their hams which they Seam from habit to prefer to Setting, no doubt contributes much to this deformity of the legs by preventing free circulation of the blood. ”

“ But the leg, both in walking and standing, is habitually extended, either completely or nearly so, and is usually in a depending position from its construction, and in order that it may bear the weight of the rest of the body. Wherefore it readily bears to be extended when necessary, and even when in bed the limb is often in this position. And when wounded, necessity subdues the understanding, since the patients become incapable of raising themselves up, so that they neither think of bending the limb nor of getting up erect, but remain lying in the same position. ”

“ Sometimes where the arm is lost the elbow will seem bent, and the hand in a fixed position on the breast. Sometimes, again, the position is non-natural, and the hand will seem to bud straight out of the shoulder, or the foot to be on the same level with the knee of the remaining leg. Sometimes, again, the position is vague; and sometimes it is ambiguous, as in another patient of Dr. Weir Mitchell's who
"lost his leg at the age of eleven, and remembers that the foot by degrees approached, and at last reached the knee. ”

“ The face often recovers its symmetry before the limbs are fully restored, but the leg may be used in locomotion before the complete recovery from paralysis, since the tone of the muscles is sufficient to keep the knee straight enough for support, as if the leg were all in one piece, while it is swung around at each step by the pelvic muscles. ”

“ Not only the articulations themselves must be so modified as to bear greater stress, but also the numerous ligaments which hold the parts of each in place. Nor can the bodies of the bones remain unstrengthened; for if they have no more than the strengths needed for previous movements they will fail to bear more violent movements. Thus, saying nothing of the required changes in the pelvis, as well as in the nerves and blood-vessels, there are, counting bones, muscles, tendons, ligaments, at least fifty different parts in each hind leg which have to be enlarged. ”

“ Individual Variation.—In nearly all of the legs, minute twigs to M. extensor iliofibularis come off the peroneal nerve near the middle of the thigh. The insertional tendon tends toward doubleness in two legs. ”

“ The lumbosacral plexus and nerves of the leg in several specimens that show variations are illustrated.
Considerable individual variation was found in both the muscles and the nerves of the leg of the species studied. Certain muscles were more variable than others. Mm. flexor digitorum longus, obturator, caudofemoralis, and extensor hallucis longus showed the greatest number of variations. Mm. vastus medialis, femoritibialis internus, flexor perforatus digiti III, extensor brevis digiti III, and abductor digiti IV did not exhibit any variations considered significant. ”

“ 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. ”

“ The exciting cause, or that which called her attention to her foot, was the alleged slipping of the tendon of the peroneus longus muscle where it passes under the outer ankle-bone. She had no theory, fancy, or any other sentiment regarding her lameness whatever. She simply dropped her toes when walking, and was obliged to lift that limb very high to advance the foot and prevent stumbling. When, in examining her, I asked her to raise the foot, she was unable to do so. The muscles moving the ankle-joint were powerless. ”

“ The ipselateral reflex is flexion at shoulder, elbow and wrist. The contra lateral fore limb at the same time is extended at shoulder, elbow and wrist. When the reflex spreads to the hind limbs the hind limb of the same side is extended at hip, knee and ankle, that of the crossed side is sometimes flexed at hip, knee and ankle, but sometimes is instead extended at hip, knee and ankle. The reflex sometimes spreads to the neck, causing the head to be turned toward the fore limb, which is the seat of the stimulation. ”