State establishment "DnEpropetrovsk Medical Academy of health Ministry of Ukraine"
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- Bursae —Three bursae
- Variations.
- Biceps femoris
- Practice class 27. The muscles and fasciae on the leg and foot. The topography of lower extremity. The aim
- Professional orientation
Variations.—The Pectineus is sometimes divided into an outer part supplied by the femoral nerve and an inner part supplied by the obturator nerve. The muscle may be attached to or inserted into the capsule of the hip-joint. The Adductor longus may be double, may extend to the knee, or be more or less united with the Pectineus. The Adductor brevis may be divided into two or three parts, or it may be united to the Adductor magnus. The Adductor magnus may be more or less segmented, the anterior and superior portion is often described as a separate muscle, the Adductor minimus. The muscle may be fused with the Quadratus femoris. Nerves.—The three Adductores and the Gracilis are supplied by the third and fourth lumbar nerves through the obturator nerve; the Adductor magnus receiving an additional branch from the sacral plexus through the sciatic. The Pectineus is supplied by the second, third, and fourth lumbar nerves through the femoral nerve, and by the third lumbar through the accessory obturator when this latter exists. Occasionally it receives a branch from the obturator nerve. Actions.—The Pectineus and three Adductores adduct the thigh powerfully; they are especially used in horse exercise, the sides of the saddle being grasped between the knees by the contraction of these muscles. In consequence of the obliquity of their insertions into the linea aspera, they rotate the thigh outward, assisting the external Rotators, and when the limb has been abducted, they draw it medialward, carrying the thigh across that of the opposite side. The Pectineus and Adductores brevis and longus assist the Psoas major and Iliacus in flexing the thigh upon the pelvis. In progression, all these muscles assist in drawing forward the lower limb. The Gracilis assists the Sartorius in flexing the leg and rotating it inward; it is also an adductor of the thigh. If the lower extremities be fixed, these muscles, taking their fixed points below, may act upon the pelvis, serving to maintain the body in an erect posture; or, if their action be continued, flex the pelvis forward upon the femur. THE MUSCLES OF THE GLUTEAL REGION Glutaeus maximus. Glutaeus medius Glutaeus minimus Tensor fasciae latae Piriformis. Obturator internus. Gemellus superior Gemellus inferior Quadratus femoris Obturator externus The Glutaeus maximus, the most superficial muscle in the gluteal region, is a broad and thick fleshy mass of a quadrilateral shape, and forms the prominence of the nates. Its large size is one of the most characteristic features of the muscular system in man, connected as it is with the power he has of maintaining the trunk in the erect posture. The muscle is remarkably coarse in structure, being made up of fasciculi lying parallel with one another and collected together into large bundles separated by fibrous septa. It arises from the posterior gluteal line of the ilium, and the rough portion of bone including the crest, immediately above and behind it; from the posterior surface of the lower part of the sacrum and the side of the coccyx; from the aponeurosis of the Sacrospinalis, the sacrotuberous ligament, and the fascia (gluteal aponeurosis) covering the Glutaeus medius. The fibers are directed obliquely downward and lateralward; those forming the upper and larger portion of the muscle, together with the superficial fibers of the lower portion, end in a thick tendinous lamina, which passes across the greater trochanter, and is inserted into the iliotibial band of the fascia lata; the deeper fibers of the lower portion of the muscle are inserted into the gluteal tuberosity between the Vastus lateralis and Adductor magnus.
The Glutaeus medius is a broad, thick, radiating muscle, situated on the outer surface of the pelvis. Its posterior third is covered by the Glutaeus maximus, its anterior two-thirds by the gluteal aponeurosis, which separates it from the superficial fascia and integument. It arises from the outer surface of the ilium between the iliac crest and posterior gluteal line above, and the anterior gluteal line below; it also arises from the gluteal aponeurosis covering its outer surface. The fibers converge to a strong flattened tendon, which is inserted into the oblique ridge which runs downward and forward on the lateral surface of the greater trochanter. A bursa separates the tendon of the muscle from the surface of the trochanter over which it glides. Variations.—The posterior border may be more or less closely united to the Piriformis, or some of the fibers end on its tendon. The Glutaeus minimus, the smallest of the three Glutaei, is placed immediately beneath the preceding. It is fan-shaped, arising from the outer surface of the ilium, between the anterior and inferior gluteal lines, and behind, from the margin of the greater sciatic notch. The fibers converge to the deep surface of a radiated aponeurosis, and this ends in a tendon which is inserted into an impression on the anterior border of the greater trochanter, and gives an expansion to the capsule of the hip-joint. A bursa is interposed between the tendon and the greater trochanter. Between the Glutaeus medius and Glutaeus minimus are the deep branches of the superior gluteal vessels and the superior gluteal nerve. The deep surface of the Glutaeus minimus is in relation with the reflected tendon of the Rectus femoris and the capsule of the hip-joint. Variations.—The muscle may be divided into an anterior and a posterior part, or it may send slips to the Piriformis, the Gemellus superior or the outer part of the origin of the Vastus lateralis. The Tensor fasciae latae (Tensor fasciae femoris) arises from the anterior part of the outer lip of the iliac crest; from the outer surface of the anterior superior iliac spine, and part of the outer border of the notch below it, between the Glutaeus medius and Sartorius; and from the deep surface of the fascia lata. It is inserted between the two layers of the iliotibial band of the fascia lata about the junction of the middle and upper thirds of the thigh. The Piriformis is a flat muscle, pyramidal in shape, lying almost parallel with the posterior margin of the Glutaeus medius. It is situated partly within the pelvis against its posterior wall, and partly at the back of the hip-joint. It arises from the front of the sacrum by three fleshy digitations, attached to the portions of bone between the first, second, third, and fourth anterior sacral foramina, and to the grooves leading from the foramina: a few fibers also arise from the margin of the greater sciatic foramen, and from the anterior surface of the sacrotuberous ligament. The muscle passes out of the pelvis through the greater sciatic foramen, the upper part of which it fills, and is inserted by a rounded tendon into the upper border of the greater trochanter behind, but often partly blended with, the common tendon of the Obturator internus and Gemelli.
The Obturator internus is situated partly within the lesser pelvis, and partly at the back of the hip-joint. It arises from the inner surface of the antero-lateral wall of the pelvis, where it surrounds the greater part of the obturator foramen, being attached to the inferior rami of the pubis and ischium, and at the side to the inner surface of the hip bone below and behind the pelvic brim, reaching from the upper part of the greater sciatic foramen above and behind to the obturator foramen below and in front. It also arises from the pelvic surface of the obturator membrane except in the posterior part, from the tendinous arch which completes the canal for the passage of the obturator vessels and nerve, and to a slight extent from the obturator fascia, which covers the muscle. The fibers converge rapidly toward the lesser sciatic foramen, and end in four or five tendinous bands, which are found on the deep surface of the muscle; these bands are reflected at a right angle over the grooved surface of the ischium between its spine and tuberosity. This bony surface is covered by smooth cartilage, which is separated from the tendon by a bursa, and presents one or more ridges corresponding with the furrows between the tendinous bands. These bands leave the pelvis through the lesser sciatic foramen and unite into a single flattened tendon, which passes horizontally across the capsule of the hip-joint, and, after receiving the attachments of the Gemelli, is inserted into the forepart of the medial surface of the greater trochanter above the trochanteric fossa. A bursa, narrow and elongated in form, is usually found between the tendon and the capsule of the hip-joint; it occasionally communicates with the bursa The Gemelli are two small muscular fasciculi, accessories to the tendon of the Obturator internus which is received into a groove between them.between the tendon and the ischium. The Gemellus superior, the smaller of the two, arises from the outer surface of the spine of the ischium, blends with the upper part of the tendon of the Obturator internus, and is inserted with it into the medial surface of the greater trochanter. It is sometimes wanting. The Gemellus inferior arises from the upper part of the tuberosity of the ischium, immediately below the groove for the Obturator internus tendon. It blends with the lower part of the tendon of the Obturator internus, and is inserted with it it into the medial surface of the greater trochanter. Rarely absent. The Quadratus femoris is a flat, quadrilateral muscle, between the Gemellus inferior and the upper margin of the Adductor magnus; it is separated from the latter by the terminal branches of the medial femoral circumflex vessels. It arises from the upper part of the external border of the tuberosity of the ischium, and is inserted into the upper part of the linea quadrata—that is, the line which extends vertically downward from the intertrochanteric crest. A bursa is often found between the front of this muscle and the lesser trochanter. Sometimes absent. The Obturator externus is a flat, triangular muscle, which covers the outer surface of the anterior wall of the pelvis. It arises from the margin of bone immediately around the medial side of the obturator foramen, viz., from the rami of the pubis, and the inferior ramus of the ischium; it also arises from the medial two-thirds of the outer surface of the obturator membrane, and from the tendinous arch which completes the canal for the passage of the obturator vessels and nerves. The fibers springing from the pubic arch extend on to the inner surface of the bone, where they obtain a narrow origin between the margin of the foramen and the attachment of the obturator membrane. The fibers converge and pass backward, lateralward, and upward, and end in a tendon which runs across the back of the neck of the femur and lower part of the capsule of the hipjoint and is inserted into the trochanteric fossa of the femur. The obturator vessels lie between the muscle and the obturator membrane; the anterior branch of the obturator nerve reaches the thigh by passing in front of the muscle, and the posterior branch by piercing it. Nerves.—The Glutaeus maximus is supplied by the fifth lumbar and first and second sacra nerves through the inferior gluteal nerve; the Glutaei medius and minimus and the Tensor fasciae latae by the fourth and fifth lumbar and first sacral nerves through the superior gluteal; the Piriformis is supplied by the first and second sacral nerves; the Gemellus inferior and Quadratus femoris by the last lumbar and first sacral nerves; the Gemellus superior and Obturator internus by the first, second, and third sacral nerves, and the Obturator externus by the third and fourth lumbar nerves through the obturator. Actions.—When the Glutaeus maximus takes its fixed point from the pelvis, it extends the femur and brings the bent thigh into a line with the body. Taking its fixed point from below, it acts upon the pelvis, supporting it and the trunk upon the head of the femur; this is especially obvious in standing on one leg. Its most powerful action is to cause the body to regain the erect position after stooping, by drawing the pelvis backward, being assisted in this action by the Biceps femoris, Semitendinosus, and Semimembranosus. The Glutaeus maximus is a tensor of the fascia lata, and by its connection with the iliotibial band steadies the femur on the articular surfaces of the tibia during standing, when the Extensor muscles are relaxed. The lower part of the muscle also acts as an adductor and external rotator of the limb. The Glutaei medius and minimus abduct the thigh, when the limb is extended, and are principally called into action in supporting the body on one limb, in conjunction with the Tensor fasciae latae. Their anterior fibers, by drawing the greater trochanter forward, rotate the thigh inward, in which action they are also assisted by the Tensor fasciae latae. The Tensor fasciae latae is a tensor of the fascia lata; continuing its action, the oblique direction of its fibers enables it to abduct the thigh and to rotate it inward. In the erect posture, acting from below, it will serve to steady the pelvis upon the head of the femur; and by means of the iliotibial band it steadies the condyles of the femur on the articular surfaces of the tibia, and assists the Glutaeus maximus in supporting the knee in the extended position. The remaining muscles are powerful external rotators of the thigh. In the sitting posture, when the thigh is flexed upon the pelvis, their action as rotators ceases, and they become abductors, with the exception of the Obturator externus, which still rotates the femur outward. THE POSTERIOR FEMORAL MUSCLES (HAMSTRING MUSCLES) Biceps femoris. Semitendinosus. Semimembranosus. The Biceps femoris (Biceps) is situated on the posterior and lateral aspect of the thigh. It has two heads of origin; one, the long head, arises from the lower and inner impression on the back part of the tuberosity of the ischium, by a tendon common to it and the Semitendinosus, and from the lower part of the sacrotuberous ligament; the other, the short head, arises from the lateral lip of the linea aspera, between the Adductor magnus and Vastus lateralis, extending up almost as high as the insertion of the Glutaeus maximus; from the lateral prolongation of the linea aspera to within 5 cm. of the lateral condyle; and from the lateral intermuscular septum. The fibers of the long head form a fusiform belly, which passes obliquely downward and lateralward across the sciatic nerve to end in an aponeurosis which covers the posterior surface of the muscle, and receives the fibers of the short head; this aponeurosis becomes gradually contracted into a tendon, which is inserted into the lateral side of the head of the fibula, and by a small slip into the lateral condyle of the tibia. At its insertion the tendon divides into two portions, which embrace the fibular collateral ligament of the knee-joint. From the posterior border of the tendon a thin expansion is given off to the fascia of the leg. The tendon of insertion of this muscle forms the lateral hamstring; the common personeal nerve descends along its medial border. Variations.—The short head may be absent; additional heads may arise from the ischial tuberosity, the linea aspera, the medial supracondylar ridge of the femur or from various other parts. A slip may pass to the Gastrocnemius. The Semitendinosus, remarkable for the great length of its tendon of insertion, is situated at the posterior and medial aspect of the thigh. It arises from the lower and medial impression on the tuberosity of the ischium, by a tendon common to it and the long head of the Biceps femoris; it also arises from an aponeurosis which connects the adjacent surfaces of the two muscles to the extent of about 7.5 cm. from their origin. The muscle is fusiform and ends a little below the middle of the thigh in a long round tendon which lies along the medial side of the popliteal fossa; it then curves around the medial condyle of the tibia and passes over the tibial collateral ligament of the knee-joint, from which it is separated by a bursa, and is inserted into the upper part of the medial surface of the body of the tibia, nearly as far forward as its anterior crest. At its insertion it gives off from its lower border a prolongation to the deep fascia of the leg and lies behind the tendon of the Sartorius, and below that of the Gracilis, to which it is united. A tendinous intersection is usually observed about the middle of the muscle. The Semimembranosus, so called from its membranous tendon of origin, is situated at the back and medial side of the thigh. It arises by a thick tendon from the upper and outer impression on the tuberosity of the ischium, above and lateral to the Biceps femoris and Semitendinosus. The tendon of origin expands into an aponeurosis, which covers the upper part of the anterior surface of the muscle; from this aponeurosis muscular fibers arise, and converge to another aponeurosis which covers the lower part of the posterior surface of the muscle and contracts into the tendon of insertion. It is inserted mainly into the horizontal groove on the posterior medial aspect of the medial condyle of the tibia. The tendon of insertion gives off certain fibrous expansions: one, of considerable size, passes upward and lateralward to be inserted into the back part of the lateral condyle of the femur, forming part of the oblique popliteal ligament of the knee-joint; a second is continued downward to the fascia which covers the Popliteus muscle; while a few fibers join the tibial collateral ligament of the joint and the fascia of the leg. The muscle overlaps the upper part of the popliteal vessels.
The tendons of insertion of the two preceding muscles form the medial hamstrings. Nerves.—The muscles of this region are supplied by the fourth and fifth lumbar and the first, second, and third sacral nerves; the nerve to the short head of the Biceps femoris is derived from the common peroneal, the other muscles are supplied through the tibial nerve. Actions.—The hamstring muscles flex the leg upon the thigh. When the knee is semiflexed, the Biceps femoris in consequence of its oblique direction rotates the leg slightly outward; and the Semitendinosus, and to a slight extent the Semimembranosus, rotate the leg inward, assisting the Popliteus. Taking their fixed point from below, these muscles serve to support the pelvis upon the head of the femur, and to draw the trunk directly backward, as in raising it from the stooping position or in feats of strength, when the body is thrown backward in the form of an arch. As already indicated on page 285, complete flexion of the hip cannot be effected unless the knee-joint is also flexed, on account of the shortness of the hamstring muscles. Note The Pectineus may consist of two incompletely separated strata; the lateral or dorsal stratum, which is constant, is supplied by a branch from the femoral nerve, or in the absence of this branch by the accessory obturator nerve; the medial or ventral stratum, when present, is supplied by the obturator nerve. Practice skills Students are supposed to identify the following anatomical structures on the samples:
Practice class 27. The muscles and fasciae on the leg and foot. The topography of lower extremity. The aim: to learn the classification, topography and structure of muscles and fasciae of the leg and foot; to show the points of origin and insertion of these muscles; to find out the functions of these muscles; to learn the topography of the lower extremity. Professional orientation: knowledge of this topic is necessary for doctors of all the specialities, especially surgeons, traumatologists, neurosurgeons, urologists. The plan of the practice class:
The muscles of the leg may be divided into three groups: anterior, posterior, and lateral. 1. THE ANTERIOR CRURAL MUSCLES Tibialis anterior. Extensor digitorum longus. Extensor hallucis longus. Peronaeus tertius.
The Tibialis anterior (Tibialis anticus) is situated on the lateral side of the tibia; it is thick and fleshy above, tendinous below. It arises from the lateral condyle and upper half or two-thirds of the lateral surface of the body of the tibia; from the adjoining part of the interosseous membrane; from the deep surface of the fascia; and from the intermuscular septum between it and the Extensor digitorum longus. The fibers run vertically downward, and end in a tendon, which is apparent on the anterior surface of the muscle at the lower third of the leg. After passing through the most medial compartments of the transverse and cruciate crural ligaments, it is inserted into the medial and under surface of the first cuneiform bone, and the base of the first metatarsal bone. This muscle overlaps the anterior tibial vessels and deep peroneal nerve in the upper part of the leg. Directory: 206 -> ENG -> Other -> Library 206 -> Space Junk: Why Gravity is More Plausible Than You Might Think 206 -> Former eurocamp participants in nba 2010-11 206 -> Cgms-41 nasa-wp-06 11 June 2013 206 -> Ap english Language and Composition Instructor 206 -> How big was the abc computer? How many vacuum tubes were in the abc? 206 -> Parent Handbook Table of Contents Introduction What is Giftedness? 206 -> 2014 Jacob K. Javits Gifted and Talented Students Education Project Abstracts pr/Award # S206A140017 Grantee: University of Connecticut Contact: Catherine A. Little Phone: 860-486-2754 Download 2.33 Mb. Share with your friends:
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