Superior gluteal veins
The superior gluteal veins are venæ comitantes of the superior gluteal artery. This article incorporates text in the public domain from page 674 of the 20th edition of Gray's Anatomy
The gluteus maximus is the main extensor muscle of the hip. It is the largest and most superficial of the three gluteal muscles and makes up a large portion of the shape and appearance of each side of the hips, its thick fleshy mass, in a quadrilateral shape, forms the prominence of the buttocks. Its large size is one of the most characteristic features of the muscular system in humans, connected as it is with the power of maintaining the trunk in the erect posture. Other primates can not sustain standing erectly; the muscle is remarkably coarse in function and structure, being made up of muscle fascicles lying parallel with one another, collected together into larger bundles separated by fibrous septa. It arises from the posterior gluteal line of the inner upper ilium, a pelvic bone, the portion of the bone including the crest of the ilium above and behind it; the fibers are lateralward. Three bursae are found in relation with the deep surface of this muscle: One of these, of large size, separates it from the greater trochanter.
When the gluteus maximus takes its fixed point from the pelvis, it extends the acetabulofemoral joint 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, 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 adductor magnus. The gluteus maximus is a tensor of the fascia lata, 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 acts as an adductor and external rotator of the limb. The upper fibers act as abductors of the hip joints; the gluteus maximus is involved from running to weight-lifting. A number of exercises focus on the gluteus maximus as well as other muscles of the upper leg. Hip thrusts Glute bridge Quadruped hip extensions Kettlebell swings Squats and variations like split squats, pistol squats and wide-stance lunges Deadlift Reverse hyperextension Four-way hip extensions Glute-ham raise Functional assessment can be useful in assessing injuries to the gluteus maximus and surrounding muscles.
These tests include: 30 Second Chair to Stand testThis test measures a participant's ability to stand up from a seated position as many times as possible in a thirty-second period of time. Testing the number of times a person can stand up in a thirty-second period helps assess strength, flexibility and endurance, which can help determine how far along a person is in rehabilitation, or how much work is still to be done. Passive piriformis stretch; the piriformis test measures flexibility of the gluteus maximus. This requires a trained professional and is based on the angle of external and internal rotation in relation to normal range of motion without injury or impingement. In other primates, gluteus maximus consists of ischiofemoralis, a small muscle that corresponds to the human gluteus maximus and originates from the ilium and the sacroiliac ligament, gluteus maximus proprius, a large muscle that extends from the ischial tuberosity to a more distant insertion on the femur. In adapting to bipedal gait, reorganization of the attachment of the muscle as well as the moment arm was required.
Table of muscles of the human body Coccyx This article incorporates text in the public domain from page 474 of the 20th edition of Gray's Anatomy Anatomy photo:13:st-0403 at the SUNY Downstate Medical Center Cross section image: pelvis/pelvis-female-17—Plastination Laboratory at the Medical University of Vienna Cross section image: pelvis/pelvis-e12-15—Plastination Laboratory at the Medical University of Vienna Cross section image: pembody/body18b—Plastination Laboratory at the Medical University of Vienna Muscles/GluteusMaximus at exrx.net
The iliotibial tract or iliotibial band is a longitudinal fibrous reinforcement of the fascia lata. The action of the ITB and its associated muscles is to extend and laterally rotate the hip. In addition, the ITB contributes to lateral knee stabilization. During knee extension the ITB moves anterior to the lateral condyle of the femur, while ~30 degrees knee flexion, the ITB moves posterior to the lateral condyle. However, it has been suggested that this is only an illusion due to the changing tension in the anterior and posterior fibers during movement, it originates at the anterolateral iliac tubercle portion of the external lip of the iliac crest and inserts at the lateral condyle of the tibia at Gerdy's tubercle. The figure shows only the proximal part of the iliotibial tract; the part of the iliotibial band which lies beneath the tensor fasciae latae is prolonged upward to join the lateral part of the capsule of the hip-joint. The tensor fasciae latae tightens the iliotibial band around the area of the knee.
This allows for bracing of the knee in lifting the opposite foot. The gluteus maximus muscle and the tensor fasciae latae insert upon the tract; the IT band stabilizes the knee both in extension and in partial flexion, is therefore used during walking and running. When a person is leaning forwards with a flexed knee, the tract is the knee's main support against gravity. Iliotibial band syndrome is a common thigh injury associated with running, it can be caused by cycling or hiking. The onset of iliotibial band syndrome occurs most in cases of overuse; the iliotibial band itself becomes inflamed in response to repeated compression on the outside of the knee or swelling of the fat pad between the bone and the tendon on the side of the knee. ITB syndrome can be caused by poor physical condition, lack of warming up before exercise, or drastic changes in activity levels; until recent anatomical studies showed differently, the held belief was that the distal portion of the iliotibial band rubbed over a bursa, however this bursa was found not to exist.
Additionally, the theory that the iliotibial band needs to stretch has been questioned as, in cadaveric studies under extreme load, the flexibility of the iliotibial band has been shown to be minimal with greater stiffness than capsular fibers. Symptoms of iliotibial band syndrome may include pain on the outside of the knee at the beginning of exercise which persists through the exercise or specific movements like running downhill and having the knee bent for prolonged periods of time; this syndrome is developed by people who increase their level of activity, such as runners who increase their mileage. Other risk factors for ITBS include gait abnormalities such as overpronation, leg length discrepancies, or bow-leggedness. ITB Syndrome is an overuse condition of the distal ITB near the lateral femoral condyle and at Gerdy's tubercle; the most vulnerable range of knee flexion for this condition is at 30-40 degrees. The IT band is of critical importance to asymmetrical standing; the upward pull on the lower attachment of the IT band thrusts the knee back into hyperextension, thereby locking the knee and converting the limb into a rigid supportive pillar.
This article incorporates text in the public domain from page 468 of the 20th edition of Gray's Anatomy
The crest of the ilium is the superior border of the wing of ilium and the superiolateral margin of the greater pelvis. The iliac crest stretches posteriorly from the anterior superior iliac spine to the posterior superior iliac spine. Behind the ASIS, it divides into an inner lip separated by the intermediate zone; the outer lip bulges laterally into the iliac tubercle. Palpable in its entire length, the crest is convex superiorly but is sinuously curved, being concave inward in front, concave outward behind, it is thinner at the center than at the extremities. The iliac crest is derived from endochondral bone. To the external lip are attached the Tensor fasciae latae, Obliquus externus abdominis, Latissimus dorsi, along its whole length the fascia lata. To the internal lip, the iliac fascia, the Transversus abdominis, Quadratus lumborum and Iliacus. Abdominal external oblique muscle Abdominal internal oblique muscle Transversus abdominis muscle Quadratus lumborum muscle Erector spinae Iliocostalis pars lumborum Longissimus pars thoracis Latissimus dorsi Tensor fasciae latae Iliacus muscle Fascia lata Iliac fascia Transverse fascia The iliac crest has a large amount of red bone marrow, thus it is the site of bone marrow harvests to collect the stem cells used in bone marrow transplantation.
The iliac crest is considered the most ideal donor site for bone grafting when a large quantity of bone is needed. For example and maxillofacial surgeons will use iliac crest bone to fill in large osseous defects of the oral cavity caused by severe periodontal disease, excess bone resorption following tooth loss, trauma, or congenital defects including alveolar clefts; the top of the iliac crests marks the level of the fourth lumbar vertebral body, above or below which lumbar puncture may be performed. Apollo's belt Hip pointer This article incorporates text in the public domain from page 234 of the 20th edition of Gray's Anatomy Bogduk, Nikolai. Clinical anatomy of the lumbar spine and sacrum. Elsevier Health Sciences. P. 106. ISBN 0-443-10119-1. Palastanga, Nigel. Anatomy and Human Movement: Structure and Function. Elsevier Health Sciences. ISBN 0-7506-8814-9. Platzer, Werner. Color Atlas of Human Anatomy, Vol. 1: Locomotor System. Thieme. ISBN 3-13-533305-1. Anatomy figure: 13:02-01 at Human Anatomy Online, SUNY Downstate Medical Center - "Superficial muscles of the gluteal region and posterior thigh."
Anatomy photo:35:os-0104 at the SUNY Downstate Medical Center - "Anterior Abdominal Wall: Osteology and Surface Anatomy " Atlas image: back_bone30 at the University of Michigan Health System - "The Back, Posterior View" Diagram at emedx.com Diagram at nih.gov
Anatomical terms of motion
Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints and specific sections of the body; the terminology used describes this motion according to its direction relative to the anatomical position of the joints. Anatomists use a unified set of terms to describe most of the movements, although other, more specialized terms are necessary for describing the uniqueness of the movements such as those of the hands and eyes. In general, motion is classified according to the anatomical plane. Flexion and extension are examples of angular motions, in which two axes of a joint are brought closer together or moved further apart. Rotational motion may occur at other joints, for example the shoulder, are described as internal or external. Other terms, such as elevation and depression, describe movement above or below the horizontal plane. Many anatomical terms derive from Latin terms with the same meaning. Motions are classified after the anatomical planes they occur in, although movement is more than not a combination of different motions occurring in several planes.
Motions can be split into categories relating to the nature of the joints involved: Gliding motions occur between flat surfaces, such as in the intervertebral discs or between the carpal and metacarpal bones of the hand. Angular motions occur over synovial joints and causes them to either increase or decrease angles between bones. Rotational motions move a structure in a rotational motion along a longitudinal axis, such as turning the head to look to either side. Apart from this motions can be divided into: Linear motions, which move in a line between two points. Rectilinear motion is motion in a straight line between two points, whereas curvilinear motion is motion following a curved path. Angular motions occur when an object is around another object decreasing the angle; the different parts of the object do not move the same distance. Examples include a movement of the knee, where the lower leg changes angle compared to the femur, or movements of the ankle; the study of movement is known as kinesiology.
A categoric list of movements of the human body and the muscles involved can be found at list of movements of the human body. The prefix hyper- is sometimes added to describe movement beyond the normal limits, such as in hypermobility, hyperflexion or hyperextension; the range of motion describes the total range of motion. For example, if a part of the body such as a joint is overstretched or "bent backwards" because of exaggerated extension motion it can be described as hyperextended. Hyperextension increases the stress on the ligaments of a joint, is not always because of a voluntary movement, it may be other causes of trauma. It may be used in surgery, such as in temporarily dislocating joints for surgical procedures; these are general terms. Most terms have a clear opposite, so are treated in pairs. Flexion and extension describe movements; these terms come from the Latin words with the same meaning. Flexion describes a bending movement that decreases the angle between a segment and its proximal segment.
For example, bending the elbow, or clenching a hand into a fist, are examples of flexion. When sitting down, the knees are flexed; when a joint can move forward and backward, such as the neck and trunk, flexion refers to movement in the anterior direction. When the chin is against the chest, the head is flexed, the trunk is flexed when a person leans forward. Flexion of the shoulder or hip refers to movement of the leg forward. Extension is the opposite of flexion, describing a straightening movement that increases the angle between body parts. For example, when standing up, the knees are extended; when a joint can move forward and backward, such as the neck and trunk, extension refers to movement in the posterior direction. Extension of the hip or shoulder moves the leg backward. Abduction is the motion of a structure away from the midline while adduction refer to motion towards the center of the body; the centre of the body is defined as the midsagittal plane. These terms come from Latin words with similar meanings, ab- being the Latin prefix indicating "away," ad- indicating "toward," and ducere meaning "to draw or pull".
Abduction refers to a motion that pulls a part away from the midline of the body. In the case of fingers and toes, it refers to spreading the digits apart, away from the centerline of the hand or foot. Abduction of the wrist is called radial deviation. For example, raising the arms up, such as when tightrope-walking, is an example of abduction at the shoulder; when the legs are splayed at the hip, such as when doing a star jump or doing a split, the legs are abducted at the hip. Adduction refers to a motion that pulls a structure or part toward the midline of the body, or towards the midline of a limb. In the case of fingers and toes, it refers to bringing the digits together, towards the centerline of the hand or foot. Adduction of the wrist is called ulnar deviation. Dropping the arms to the sides, bringing the knees together, are examples of adduction. Ulnar deviation is the hand moving towards the ulnar styloid. Radial deviation is the hand moving towards the radial styloid; the terms elevation and depression refer to movement below the horizontal.
They derive from the Latin terms with similar meaningsElevation refers to movement in a superior direction. For example
Posterior gluteal line
The posterior gluteal line, the shortest of the three gluteal lines, begins at the iliac crest, about 5 cm in front of its posterior extremity. Behind this line is a narrow semilunar surface, the upper part of, rough and gives origin to a portion of the Gluteus maximus; this article incorporates text in the public domain from page 232 of the 20th edition of Gray's Anatomy
The pelvis is either the lower part of the trunk of the human body between the abdomen and the thighs or the skeleton embedded in it. The pelvic region of the trunk includes the bony pelvis, the pelvic cavity, the pelvic floor, below the pelvic cavity, the perineum, below the pelvic floor; the pelvic skeleton is formed in the area of the back, by the sacrum and the coccyx and anteriorly and to the left and right sides, by a pair of hip bones. The two hip bones connect the spine with the lower limbs, they are attached to the sacrum posteriorly, connected to each other anteriorly, joined with the two femurs at the hip joints. The gap enclosed by the bony pelvis, called the pelvic cavity, is the section of the body underneath the abdomen and consists of the reproductive organs and the rectum, while the pelvic floor at the base of the cavity assists in supporting the organs of the abdomen. In mammals, the bony pelvis has a gap in the middle larger in females than in males, their young pass through this gap.
The pelvic region of the trunk is the lower part of the trunk, between the thighs. It includes several structures: the bony pelvis, the pelvic cavity, the pelvic floor, the perineum; the bony pelvis is the part of the skeleton embedded in the pelvic region of the trunk. It is subdivided into the pelvic spine; the pelvic girdle is composed of the appendicular hip bones oriented in a ring, connects the pelvic region of the spine to the lower limbs. The pelvic spine consists of the coccyx; the pelvic cavity defined as a small part of the space enclosed by the bony pelvis, delimited by the pelvic brim above and the pelvic floor below. Each hip bone consists of 3 sections, ilium and pubis. During childhood, these sections are separate bones, joined by the triradiate cartilage. During puberty, they fuse together to form a single bone; the pelvic cavity is a body cavity, bounded by the bones of the pelvis and which contains reproductive organs and the rectum. A distinction is made between the lesser or true pelvis inferior to the terminal line, the greater or false pelvis above it.
The pelvic inlet or superior pelvic aperture, which leads into the lesser pelvis, is bordered by the promontory, the arcuate line of ilium, the iliopubic eminence, the pecten of the pubis, the upper part of the pubic symphysis. The pelvic outlet or inferior pelvic aperture is the region between the subpubic angle or pubic arch, the ischial tuberosities and the coccyx. Ligaments: obturator membrane, inguinal ligament Alternatively, the pelvis is divided into three planes: the inlet and outlet; the pelvic floor has two inherently conflicting functions: One is to close the pelvic and abdominal cavities and bear the load of the visceral organs. To achieve both these tasks, the pelvic floor is composed of several overlapping sheets of muscles and connective tissues; the pelvic diaphragm is composed of the coccygeus muscle. These arise between the symphysis and the ischial spine and converge on the coccyx and the anococcygeal ligament which spans between the tip of the coccyx and the anal hiatus; this leaves a slit for the urogenital openings.
Because of the width of the genital aperture, wider in females, a second closing mechanism is required. The urogenital diaphragm consists of the deep transverse perineal which arises from the inferior ischial and pubic rami and extends to the urogential hiatus; the urogenital diaphragm is reinforced posteriorly by the superficial transverse perineal. The external anal and urethral sphincters close the urethra; the former is surrounded by the bulbospongiosus which narrows the vaginal introitus in females and surrounds the corpus spongiosum in males. Ischiocavernosus clitoridis. Modern humans are to a large extent characterized by large brains; because the pelvis is vital to both locomotion and childbirth, natural selection has been confronted by two conflicting demands: a wide birth canal and locomotion efficiency, a conflict referred to as the "obstetrical dilemma". The female pelvis, or gynecoid pelvis, has evolved to its maximum width for childbirth—a wider pelvis would make women unable to walk.
In contrast, human male pelvises are not constrained by the need to give birth and therefore are more optimized for bipedal locomotion. The principal differences between male and female true and false pelvis include: The female pelvis is larger and broader than the male pelvis, taller and more compact; the female inlet is oval in shape, while the male sacral promontory projects further. The sides of the male pelvis converge from the inlet to the outlet, whereas the sides of the female pelvis are wider apart; the angle between