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
Gray's Anatomy is an English language textbook of human anatomy written by Henry Gray and illustrated by Henry Vandyke Carter. Earlier editions were called Anatomy: Descriptive and Surgical, Anatomy of the Human Body and Gray's Anatomy: Descriptive and Applied, but the book's name is shortened to, editions are titled, Gray's Anatomy; the book is regarded as an influential work on the subject, has continued to be revised and republished from its initial publication in 1858 to the present day. The latest edition of the book, the 41st, was published in September 2015; the English anatomist Henry Gray was born in 1827. He studied the development of the endocrine glands and spleen and in 1853 was appointed Lecturer on Anatomy at St George's Hospital Medical School in London. In 1855, he approached his colleague Henry Vandyke Carter with his idea to produce an inexpensive and accessible anatomy textbook for medical students. Dissecting unclaimed bodies from workhouse and hospital mortuaries through the Anatomy Act of 1832, the two worked for 18 months on what would form the basis of the book.
Their work was first published in 1858 by John William Parker in London. It was dedicated by Gray to 1st Baronet. An imprint of this English first edition was published in the United States in 1859, with slight alterations. Gray prepared a second, revised edition, published in the United Kingdom in 1860 by J. W. Parker. However, Gray died the following year, at the age of 34, having contracted smallpox while treating his nephew, his death had come just three years after the initial publication of his Anatomy Descriptive and Surgical. So, the work on his much-praised book was continued by others. Longman's publication began in 1863, after their acquisition of the J. W. Parker publishing business; this coincided with the publication date of the third British edition of Gray's Anatomy. Successive British editions of Gray's Anatomy continued to be published under the Longman, more Churchill Livingstone/Elsevier imprints, reflecting further changes in ownership of the publishing companies over the years.
The full American rights were purchased by Blanchard and Lea, who published the first of twenty-five distinct American editions of Gray's Anatomy in 1862, whose company became Lea & Febiger in 1908. Lea & Febiger continued publishing the American editions until the company was sold in 1990; the first American publication was edited by Richard James Dunglison, whose father Robley Dunglison was physician to Thomas Jefferson. Dunglison edited the next four editions; these were: the Second American Edition. W. W. Keen edited the next two editions, namely: the New American from the Eleventh English Edition. In September 1896, reference to the English edition was dropped and it was published as the Fourteenth Edition, edited by Bern B. Gallaudet, F. J. Brockway, J. P. McMurrich, who edited the Fifteenth Edition. There is an edition dated 1896 which does still reference the English edition stating it is "A New Edition, Thoroughly Revised by American Authorities, from the thirteenth English Edition" and edited by T. Pickering Pick, F.
R. C. S. and published by Lea Brothers & Co. Philadelphia and New York; the Sixteenth Edition was edited by J. C. DaCosta, the Seventeenth by DaCosta and E. A. Spitzka. Spitzka edited the Eighteenth and Nineteenth editions, in October 1913, R. Howden edited the New American from the Eighteenth English Edition; the "American" editions continued with consecutive numbering from the Twentieth onwards, with W. H. Lewis editing the 20th, 21st, 22nd, 23rd, 24th. C. M. Gross edited the 25th, 26th, 27th, 28th, 29th. Carmine D. Clemente extensively revised the 30th edition. With the sale of Lea & Febiger in 1990, the 30th edition was the last American Edition. Sometimes separate editing efforts with mismatches between British and American edition numbering led to the existence, for many years, of two main "flavours" or "branches" of Gray's Anatomy: the U. S. and the British one. This can cause misunderstandings and confusion when quoting from or trying to purchase a certain edition. For example, a comparison of publishing histories shows that the American numbering kept apace with the British up until the 16th editions in 1905, with the American editions either acknowledging the English edition, or matching the numbering in the 14th, 15th and 16th editions.
The American numbering crept ahead, with the 17th American edition published in 1908, while the 17th British edition was published in 1909. This increased to a three-year gap for the 18th and 19th editions, leading to the 1913 publication of the New American from the Eighteenth English, which brought the numbering back into line. Both 20th editions were published in the same year. Thereafter, it was the British numbering that pushed ahead, with the 21st British edition in 1920, the 21st American edition in 1924; this discrepancy continued to increase, so that the 30th British edition was published in 1949, while the 30th and last American edition was published in 1984. The newest, 41st edition of Gray's Anatomy was published on 25 September 2015 by Elsevier in both print and online versions, and
The human back is the large posterior area of the human body, rising from the top of the buttocks to the back of the neck and the shoulders. It is the surface of the body opposite from the chest; the vertebral column creates a central area of recession. The breadth of the back is created by the shoulders at the pelvis at the bottom. Back pain is a common medical condition benign in origin; the central feature of the human back is the vertebral column the length from the top of the thoracic vertebrae to the bottom of the lumbar vertebrae, which houses the spinal cord in its spinal canal, which has some curvature that gives shape to the back. The ribcage extends from the spine at the top of the back, more than halfway down the length of the back, leaving an area with less protection between the bottom of the ribcage and the hips; the width of the back at the top is defined by the broad, flat bones of the shoulders. The muscles of the back can be divided into three distinct groups; the superficial group known as the appendicular group, is associated with movement of the appendicular skeleton.
It is composed of latissimus dorsi, rhomboid major, rhomboid minor and levator scapulae. It is innervated by anterior rami of spinal nerves, reflecting its embryological origin outside the back; the intermediate group is known as respiratory group as it may serve a respiratory function. It is composed of serratus posterior serratus posterior inferior. Like the superficial group, it is innervated by anterior rami of spinal nerves; the deep group known as the intrinsic group due to its embryological origin in the back, can be further subdivided into four groups: Spinotransversales - composed of splenius capitis and splenius cervicis. Erector spinae - composed of iliocostalis and spinalis Transversospinales - composed of semispinalis and rotatores Segmental muscles - composed of levatores costarum and intertransversariiThe deep group is innervated by the posterior rami of spinal nerves; the lungs are within the ribcage, extend to the back of the ribcage making it possible for them to be listened into through the back.
The kidneys are situated beneath the muscles in the area below the end of the ribcage, loosely connected to the peritoneum. A strike to the lower back can damage the kidneys of the person being hit; the skin of the human back is thicker and has fewer nerve endings than the skin on any other part of the torso. With some notable exceptions, it tends to have less hair than the chest on men; the upper-middle back is the one area of the body which a typical human under normal conditions might be unable to physically touch. The skin of the back is innervated by the dorsal cutaneous branches, as well as the lateral abdominal cutaneous branches of intercostal nerves; the intricate anatomy of the back provides support for the head and trunk of the body, strength in the trunk of the body, as well as a great deal of flexibility and movement. The upper back has the most structural support, with the ribs attached to each level of the thoracic spine and limited movement; the lower back allows for movement in back bending and forward bending.
It does not permit twisting. The back comprises interconnecting nerves, muscles and tendons, all of which can be a source of pain. Back pain is the second most common type of pain in adults. By far the most common cause of back pain is muscle strain; the back muscles can heal themselves within a couple of weeks, but the pain can be intense and debilitating. Other common sources of back pain include disc problems, such as degenerative disc disease or a lumbar disc herniation, many types of fractures, such as spondylolisthesis or an osteoporotic fracture, or osteoarthritis; the curvature of the female back is a frequent theme in paintings, because the sensibilities of many cultures permit the back to be shown nude - implying full nudity without displaying it. Indeed, the practice of showing explicitness on the lower back has been performed for centuries. Certain articles of clothing, such as the haltertop and the backless dress, are designed to expose the back in this manner; the lower back is exposed by many types of shirts in woman's fashion, the more conservative shirts and blouses will reveal the lower back.
This happens for a variety of reasons- the lower waist area is a pivot point for the body and lengthens and arches as a person sits or bends. Secondly, woman's fashion favors tops that are waist length, allowing the back to be left bare during slight movement, bending or sitting; the back serves as the largest canvas for body art on the human body. Because of its size and the relative lack of hair, the back presents an ideal canvas on the human body for lower back tattoos among young women. Indeed, some individuals have tattoos. Others have smaller tattoos at significant locations, such as the shoulder blade or the bottom of the back. Many English idioms mention the back highlighting it as an area of vulnerability; the back is a symbol of strength and hard work, with those seeking physical labor looking for "strong backs", workers being implored to "put their back into it". Flage
The longissimus is the muscle lateral to the semispinalis muscles. It is the longest subdivision of the erector spinae muscles that extends forward into the transverse processes of the posterior cervical vertebrae; the longissimus thoracis is the largest of the continuations of the erector spinae. In the lumbar region, where it is as yet blended with the iliocostalis, some of its fibers are attached to the whole length of the posterior surfaces of the transverse processes and the accessory processes of the lumbar vertebrae, to the anterior layer of the lumbodorsal fascia. In the thoracic region, it is inserted, by rounded tendons, into the tips of the transverse processes of all the thoracic vertebrae, by fleshy processes into the lower nine or ten ribs between their tubercles and angles; the longissimus cervicis, situated medial to the longissimus thoracis, arises by long, thin tendons from the summits of the transverse processes of thoracic vertebræ 1–5, is inserted by similar tendons into the posterior tubercles of the transverse processes of cervical vertebrae 2–6.
The longissimus capitis lies medial to the longissimus cervicis, between it and the semispinalis capitis. It arises by tendons from the transverse processes of the upper four or five thoracic vertebrae, the articular processes of the lower three or four cervical vertebrae, is inserted into the posterior margin of the mastoid process, beneath the splenius capitis and sternocleidomastoid, it is always crossed by a tendinous intersection near its insertion. Spinalis Anatomy figure: 01:06-05 at Human Anatomy Online, SUNY Downstate Medical Center - "Intrinsic muscles of the back." Cross section image: pembody/body12a—Plastination Laboratory at the Medical University of Vienna Dissection at ithaca.edu This article incorporates text in the public domain from page 399 of the 20th edition of Gray's Anatomy
The multifidus muscle consists of a number of fleshy and tendinous fasciculi, which fill up the groove on either side of the spinous processes of the vertebrae, from the sacrum to the axis. While thin, the Multifidus muscle plays an important role in stabilizing the joints within the spine; the multifidus is one of the transversospinales. Located just superficially to the spine itself, the multifidus muscle spans three joint segments and works to stabilize these joints at each level; the stiffness and stability makes each vertebra work more and reduces the degeneration of the joint structures caused by friction from normal physical activity. These fasciculi arise: in the sacral region: from the back of the sacrum, as low as the fourth sacral foramen, from the aponeurosis of origin of the sacrospinalis, from the medial surface of the posterior superior iliac spine, from the posterior sacroiliac ligaments. in the lumbar region: from all the mamillary processes. In the thoracic region: from all the transverse processes.
In the cervical region: from the articular processes of the lower four vertebrae. Each fasciculus, passing obliquely upward and medially, is inserted into the whole length of the spinous process of one of the vertebræ above; these fasciculi vary in length: the most superficial, the longest, pass from one vertebra to the third or fourth above. The multifidus lies deep relative to the spinal erectors, transverse abdominis, abdominal internal oblique muscle and abdominal external oblique muscle. Dysfunction in the lumbar multifidus muscles is associated with low back pain; the dysfunction can be caused by inhibition of pain by the spine. The dysfunction persists after the pain has disappeared; such persistence may help explain the high recurrence rates of low back pain. Persistent lumbar multifidus dysfunction is diagnosed by atrophic replacement of the multifidus with fat, as visualized by magnetic resonance imaging or ultrasound. One way to help recruit and strengthen the lumbar multifidus muscles is by tensing the pelvic floor muscles for a few seconds "as if stopping urination midstream".
Rotatores muscles This article incorporates text in the public domain from page 400 of the 20th edition of Gray's Anatomy Multifidus_1 at the Duke University Health System's Orthopedics program PTCentral Dissection at ithaca.edu
The coracoid process is a small hook-like structure on the lateral edge of the superior anterior portion of the scapula. Pointing laterally forward, it, together with the acromion, serves to stabilize the shoulder joint, it is palpable in the deltopectoral groove between the pectoralis major muscles. The coracoid process is a thick curved process attached by a broad base to the upper part of the neck of the scapula; the ascending portion, flattened from before backward, presents in front a smooth concave surface, across which the subscapularis passes. The horizontal portion is flattened from above downward. On the medial part of the root of the coracoid process is a rough impression for the attachment of the conoid ligament, it is the site of attachment for several structures: The pectoralis minor muscle – to 3rd, 4th, 5th and on some rare occasions, 6th rib. The short head of biceps brachii muscle – to Radial tuberosity; the coracobrachialis muscle – to medial humerus. The coracoclavicular ligament – to the clavicle.
The coracoacromial ligament – to the acromion The coracohumeral ligament – to the humerus The superior transverse scapular ligament – from the base of the coracoid to the medial portion of the suprascapular notch The coracoid process is palpable just below the lateral end of the clavicle. It is otherwise known as the "Surgeon's Lighthouse" because it serves as a landmark to avoid neurovascular damage. Major neurovascular structures enter the upper limb medial to the coracoid process, so that surgical approaches to the shoulder region should always take place laterally to the coracoid process. In monotremes, the coracoid is a separate bone. Reptiles and frogs possess a bone by this name, but is not homologous with the coracoid process of mammals. Analyses of the size and shape of the coracoid process in Australopithecus africanus have shown that in this species it displayed a prominent dorsolateral tubercle placed more laterally than in modern humans; this reflect, according to one interpretation, a scapula positioned high on a funnel-shaped thorax and a clavicle positioned obliquely as in extant great apes.
Anatomy image: skel/scapula2 at Human Anatomy Lecture, Pennsylvania State University Coracoid Process - BlueLink Anatomy, University of Michigan Medical School
The rib cage is the arrangement of ribs attached to the vertebral column and sternum in the thorax of most vertebrates, that encloses and protects the heart and lungs. In humans, the rib cage known as the thoracic cage, is a bony and cartilaginous structure which surrounds the thoracic cavity and supports the shoulder girdle to form the core part of the human skeleton. A typical human rib cage consists of 24 ribs in 12 pairs, the sternum and xiphoid process, the costal cartilages, the 12 thoracic vertebrae. Together with the skin and associated fascia and muscles, the rib cage makes up the thoracic wall and provides attachments for the muscles of the neck, upper abdomen, back; the rib cage has a major function in the respiratory system. Ribs are described based on their connection with the sternum. All ribs are numbered accordingly one to twelve. Ribs that articulate directly with the sternum are called true ribs, whereas those that connect indirectly via cartilage are termed false ribs. Floating ribs are not attached to the sternum at all.
The terms true ribs and false ribs describe rib pairs that are directly or indirectly attached to the sternum. The first seven rib pairs known as the fixed or vertebrosternal ribs are the true ribs as they connect directly to the sternum, their elasticity allows rib cage movement for respiratory activity. The phrase floating rib refers to the eleventh and twelfth rib pairs; these ribs are small and delicate, include a cartilaginous tip. The spaces between the ribs are known as intercostal spaces; each rib consists of a head, a shaft. All ribs are attached posteriorly to the thoracic vertebrae, they are numbered to match the vertebra -- one to twelve, from top to bottom. The head of the rib is the end part closest to the vertebrae, it is marked by a kidney-shaped articular surface, divided by a horizontal crest into two articulating regions. The upper region articulates with the inferior costal facet on the vertebra above, the larger region articulates with the superior costal facet on the vertebra with the same number.
The transverse process of a thoracic vertebra articulates at the transverse costal facet with the tubercle of the rib of the same number. The crest gives attachment to the intra-articular ligament; the neck of the rib is the flattened part. The neck is about 3 cm long, its anterior surface is flat and smooth, whilst its posterior is perforated by numerous foramina and its surface rough, to give attachment to the ligament of the neck. Its upper border presents a rough crest for the attachment of the anterior costotransverse ligament. On the posterior surface at the neck, is an eminence—the tubercle that consists of an articular and a non-articular portion; the articular portion is the lower and more medial of the two and presents a small, oval surface for articulation with the transverse costal facet on the end of the transverse process of the lower of the two vertebrae to which the head is connected. The non-articular portion is a rough elevation and affords attachment to the ligament of the tubercle.
The tubercle is much more prominent in the upper ribs than in the lower ribs. The angle of a rib may both refer to the bending part of it, a prominent line in this area, a little in front of the tubercle; this line is directed laterally. At this point, the rib is bent in two directions, at the same time twisted on its long axis; the distance between the angle and the tubercle is progressively greater from the second to the tenth ribs. The area between the angle and the tubercle is rounded and irregular, serves for the attachment of the longissimus dorsi muscle; the first rib is the most curved and the shortest of all the ribs. The head is small and rounded, possesses only a single articular facet, for articulation with the body of the first thoracic vertebra; the neck is rounded. The tubercle and prominent, is placed on the outer border, it bears a small facet for articulation with the transverse costal facet on the transverse process of T1. There is no angle, but at the tubercle, the rib is bent, with the convexity upward, so that the head of the bone is directed downward.
The upper surface of the body is marked by two shallow grooves, separated from each other by a slight ridge prolonged internally into a tubercle, the scalene tubercle, for the attachment of the anterior scalene. Behind the posterior groove is a rough area for the attachment of the medial scalene; the under surface is smooth and without a costal groove. The outer border is convex and rounded, at its posterior part gives attachment to the first digitation of the serratus anterior; the inner border is concave and sharp, marked about its center by the scalene tubercle. The anterior extremity is larger and