Anatomical terminology uses many unique terms, suffixes, and prefixes deriving from Ancient Greek and Latin. These terms can be confusing to those unfamiliar with them, but can be more precise, reducing ambiguity and errors. Also, since these anatomical terms are not used in everyday conversation, their meanings are less likely to change, and less likely to be misinterpreted.
To illustrate how inexact day-to-day language can be: a scar "above the wrist" could be located on the forearm two or three inches away from the hand or at the base of the hand; and could be on the palm-side or back-side of the arm. By using precise anatomical terminology such ambiguity is eliminated.[1]
An international standard for anatomical terminology, Terminologia Anatomica has been created.
Word formation
Anatomical terminology has quite regular morphology: the same prefixes and suffixes are used to add meanings to different roots. The root of a term often refers to an organ or tissue. For example, the Latin names of structures such as musculus biceps brachii can be split up: musculus for muscle, biceps for "two-headed", and brachii as in the brachial region of the arm. The first word describes what structure is being spoken about, the second describes an instance of this structure, and the third points to its location.[1]
When describing the position of anatomical structures, structures may be described according to the anatomical landmark they are near. These landmarks may include structures, such as the umbilicus or sternum, or anatomical lines, such as the midclavicular line from the centre of the clavicle. The cephalon or cephalic region refers to the head. This area is further differentiated into the cranium (skull), facies (face), frons (forehead), oculus (eye area), auris (ear), bucca (cheek), nasus (nose), os (mouth), and mentum (chin). The neck area is called the cervix or cervical region. Examples of structures named according to this include the frontalis muscle, submental lymph nodes, buccal membrane and orbicularis oculi muscle.
Sometimes, unique terminology is used to reduce confusion in different parts of the body. For example, different terms are used when it comes to the skull in compliance with its embryonic origin and its tilted position compared to in other animals. Here, rostral refers to proximity to the front of the nose, and is particularly used when describing the skull.[2]:4 Similarly, different terminology is often used in the arms, in part to reduce ambiguity as to what the "front", "back", "inner" and "outer" surfaces are. For this reason, the terms below are used:
International morphological terminology is used by the colleges of medicine and dentistry and other areas of the health sciences. It facilitates communication and exchanges between scientists from different countries of the world and it is used daily in the fields of research, teaching and medical care. The international morphological terminology refers to morphological sciences as a biological sciences' branch. In this field, the form and structure are examined as well as the changes or developments in the organism. It is descriptive and functional. Basically, it covers the gross anatomy and the microscopic (histology and cytology) of living beings. It involves both development anatomy (embryology) and the anatomy of the adult. It also includes comparative anatomy between different species. The vocabulary is extensive, varied and complex, and requires a systematic presentation.
The current international standard for human anatomical terminology is based on the Terminologia Anatomica (TA). It was developed by the Federative Committee on Anatomical Terminology (FCAT) and the International Federation of Associations of Anatomists (IFAA) and was released in 1998.[6] It supersedes the previous standard, Nomina Anatomica.[7]Terminologia Anatomica contains terminology for about 7500 human gross (macroscopic) anatomical structures.[8] For microanatomy, known as histology, a similar standard exists in Terminologia Histologica, and for embryology, the study of development, a standard exists in Terminologia Embryologica. These standards specify generally accepted names that can be used to refer to histological and embryological structures in journal articles, textbooks, and other areas. As of September 2016, two sections of the Terminologia Anatomica, including central nervous system and peripheral nervous system, were merged to form the Terminologia Neuroanatomica.[9]
Recently, the Terminologia Anatomica has been perceived with a considerable criticism regarding its content including coverage, grammar and spelling mistakes, inconsistencies, and errors.[10]
Anatomical terminology is often chosen to highlight the relative location of body structures. For instance, an anatomist might describe one band of tissue as "inferior to" another or a physician might describe a tumor as "superficial to" a deeper body structure.[1]
Anatomical terms used to describe location are based on a body positioned in what is called the standard anatomical position. This position is one in which a person is standing, feet apace, with palms forward and thumbs facing outwards.[11] Just as maps are normally oriented with north at the top, the standard body "map", or anatomical position, is that of the body standing upright, with the feet at shoulder width and parallel, toes forward. The upper limbs are held out to each side, and the palms of the hands face forward.[1]
Using the standard anatomical position reduces confusion. It means that regardless of the position of a body, the position of structures within it can be described without ambiguity.[1]
The human body is shown in anatomical position in an anterior view and a posterior view. The regions of the body are labeled in boldface.
In terms of anatomy, the body is divided into regions. In the front, the trunk is referred to as the "thorax" and "abdomen". The back as a general area is the dorsum or dorsal area, and the lower back is the lumbus or lumbar region. The shoulder blades are the scapular area and the breastbone is the sternal region. The abdominal area is the region between the chest and the pelvis. The breast is also called the mammary region, the armpit as the axilla and axillary, and the navel as the umbilicus and umbilical. The pelvis is the lower torso, between the abdomen and the thighs. The groin, where the thigh joins the trunk, are the inguen and inguinal area.
The entire arm is referred to as the brachium and brachial, the front of the elbow as the antecubitis and antecubital, the back of the elbow as the olecranon or olecranal, the forearm as the antebrachium and antebrachial, the wrist as the carpus and carpal area, the hand as the manus and manual, the palm as the palma and palmar, the thumb as the pollex, and the fingers as the digits, phalanges, and phalangeal. The buttocks are the gluteus or gluteal region and the pubic area is the pubis.
Anatomists divide the lower limb into the thigh (the part of the limb between the hip and the knee) and the leg (which refers only to the area of the limb between the knee and the ankle).[11] The thigh is the femur and the femoral region. The kneecap is the patella and patellar while the back of the knee is the popliteus and popliteal area. The leg (between the knee and the ankle) is the crus and crural area, the lateral aspect of the leg is the peroneal area, and the calf is the sura and sural region. The ankle is the tarsus and tarsal, and the heel is the calcaneus or calcaneal. The foot is the pes and pedal region, and the sole of the foot is the planta and plantar. As with the fingers, the toes are also called the digits, phalanges, and phalangeal area. The big toe is referred to as the hallux.
Abdomen
Abdominal regions are used for example to localize pain.
To promote clear communication, for instance about the location of a patient's abdominal pain or a suspicious mass, the abdominal cavity can be divided into either nine regions or four quadrants.[1]
Quadrants
The abdomen may be divided into four quadrants, more commonly used in medicine, subdivides the cavity with one horizontal and one vertical line that intersect at the patient's umbilicus (navel).[1] The right upper quadrant (RUQ) includes the lower right ribs, right side of the liver, and right side of the transverse colon. The left upper quadrant (LUQ) includes the lower left ribs, stomach, spleen, and upper left area of the transverse colon. The right lower quadrant (RLQ) includes the right half of the small intestines, ascending colon, right pelvic bone and upper right area of the bladder. The left lower quadrant (LLQ) contains the left half of the small intestine and left pelvic bone.[11]
Regions
The more detailed regional approach subdivides the cavity into nine regions, with two vertical and two horizontal lines drawn according to landmark structures. The vertical; or midclavicular lines, are drawn as if dropped from the midpoint of each clavicle. The superior horizontal line is the subcostal line, drawn immediately inferior to the ribs.[1] The inferior horizontal line is called the intertubercular line, and is to cross the iliac tubercles, found at the superior aspect of the pelvis. The upper right square is the right hypochondriac region and contains the base of the right ribs. The upper left square is the left hypochondriac region and contains the base of the left ribs.
The epigastric region is the upper central square and contains the bottom edge of the liver as well as the upper areas of the stomach. The diaphragm curves like an upside down U over these three regions. The central right region is called the right lumbar region and contains the ascending colon and the right edge of the small intestines. The central square contains the transverse colon and the upper regions of the small intestines. The left lumbar region contains the left edge of the transverse colon and the left edge of the small intestine. The lower right square is the right iliac region and contains the right pelvic bones and the ascending colon. The lower left square is the left iliac region and contains the left pelvic bone and the lower left regions of the small intestine. The lower central square contains the bottom of the pubic bones, upper regions of the bladder and the lower region of the small intestine.[11]
Standard terms
When anatomists refer to the right and left of the body, it is in reference to the right and left of the subject, not the right and left of the observer. When observing a body in the anatomical position, the left of the body is on the observer's right, and vice versa.
These standardized terms avoid confusion. Examples of terms include:[2]:4
Anterior and posterior, which describe structures at the front (anterior) and back (posterior) of the body. For example, the toes are anterior to the heel, and the popliteus is posterior to the patella.[1]
Superior and inferior, which describe a position above (superior) or below (inferior) another part of the body. For example, the orbits are superior to the oris, and the pelvis is inferior to the abdomen.[1]
Proximal and distal, which describe a position that is closer to (proximal) or farther from (distal) the trunk of the body.[1] For example, the shoulder is proximal to the arm, and the foot is distal to the knee.
Superficial and deep, which describe structures that are closer to (superficial) or farther from (deep) the surface of the body. For example, the skin is superficial to the bones, and the brain is deep to the skull.[1] Sometimes profound is used synonymously with deep.
Medial and lateral, which describe a position that is closer to (medial) or farther from (lateral) the midline of the body. For example, the shoulders are lateral to the heart, and the umbilicus is medial to the hips. The medial side of the left knee is the side toward the opposite knee.
Radial and ulnar, which describe only structures at or distal to the elbow and may be used interchangeably with medial and lateral in that particular area because they are less confusing. Examples: The thumb is on the radial side of the hand (the same as saying the lateral side); the ulnar side of the wrist is the side toward the little finger (medial side).
Ventral and dorsal, which describe structures derived from the front (ventral) and back (dorsal) of the embryo, before limb rotation.
Rostral and caudal, which describe structures close to (rostral) or farther from (caudal) the nose. For example, the eyes are rostral to the back of the skull, and the tailbone is caudal to the chest.
Cranial and caudal, which describe structures close to the top of the skull (cranial), and towards the bottom of the body (caudal).
Occasionally, sinister for left, and dexter for right are used.
Paired, referring to a structure that is present on both sides of the body. For example, the hands are paired structures.
Axes
Each locational term above can define the direction of a vector, and pairs of them can define axes, that is, lines of orientation. For example, blood can be said to flow in a proximal or distal direction, and anteroposterior, mediolateral, and inferosuperior axes are lines along which the body extends, like the X, Y, and Z axes of a Cartesian coordinate system. An axis can be projected to a corresponding plane.
The three anatomical planes of the body: the sagittal, transverse (or horizontal), frontal planes
Anatomy is often described in planes, referring to two-dimensional sections of the body. A section is a two-dimensional surface of a three-dimensional structure that has been cut. A plane is an imaginary two-dimensional surface that passes through the body. Three planes are commonly referred to in anatomy and medicine:[1][2]:4
The sagittal plane is the plane that divides the body or an organ vertically into right and left sides. If this vertical plane runs directly down the middle of the body, it is called the midsagittal or median plane. If it divides the body into unequal right and left sides, it is called a parasagittal plane, or less commonly a longitudinal section.[1]
The frontal plane is the plane that divides the body or an organ into an anterior (front) portion and a posterior (rear) portion. The frontal plane is often referred to as a coronal plane, following Latincorona, which means "crown".[1]
The transverse plane is the plane that divides the body or organ horizontally into upper and lower portions. Transverse planes produce images referred to as cross sections.[1]
Functional state
Anatomical terms may be used to describe the functional state of an organ: [citation needed]
Anastomoses refers to the connection between two structures previously branched out, such as blood vessels or leaf veins.
The term anatomical variation is used to refer to a difference in anatomical structures that is not regarded as a disorder. Many structures vary slightly between people, for example muscles that attach in slightly different places. For example, the presence or absence of the palmaris longus tendon. Anatomical variation is unlike congenital anomalies, which are considered a disorder.[12]
Joints, especially synovial joints allow the body a tremendous range of movements. Each movement at a synovial joint results from the contraction or relaxation of the muscles that are attached to the bones on either side of the articulation. The type of movement that can be produced at a synovial joint is determined by its structural type.
Movement types are generally paired, with one being the opposite of the other. Body movements are always described in relation to the anatomical position of the body: upright stance, with upper limbs to the side of body and palms facing forward.[11]
General motion
Terms describing motion in general include:
Flexion and extension, which refer to a movement that decreases (flexion) or increases (extension) the angle between body parts. For example, when standing up, the knees are extended.
Abduction and adduction refers to a motion that pulls a structure away from (abduction) or towards (adduction) the midline of the body or limb. For example, a star jump requires the legs to be abducted.
Internal rotation (or medial rotation) and external rotation (or lateral rotation) refers to rotation towards (internal) or away from (external) the center of the body. For example, the lotus position posture in yoga requires the legs to be externally rotated.
Elevation and depression refer to movement in a superior (elevation) or inferior (depression) direction. Primarily refers to movements involving the scapula and mandible.[13]
Special motions of the hands and feet
These terms refer to movements that are regarded as unique to the hands and feet:[14]:590–7
Dorsiflexion and plantarflexion refers to flexion (dorsiflexion) or extension (plantarflexion) of the foot at the ankle. For example, plantarflexion occurs when pressing the brake pedal of a car.
Palmarflexion and dorsiflexion refer to movement of the flexion (palmarflexion) or extension (dorsiflexion) of the hand at the wrist. For example, prayer is often conducted with the hands dorsiflexed.
Pronation and supination refer to rotation of the forearm or foot so that in the anatomical position the palm or sole is facing anteriorly (supination) or posteriorly (pronation). For example, if a person is holding a bowl of soup in one hand, the hand is "supinated" and the thumb will point away from the body midline and the palm will be superior; if the hands are typing on a computer keyboard, they will be "pronated" with the thumbs toward the body midline and the palms inferior.
Eversion and inversion refer to movements that tilt the sole of the foot away from (eversion) or towards (inversion) the midline of the body.
The biceps brachii flex the lower arm. The brachioradialis, in the forearm, and brachialis, located deep to the biceps in the upper arm, are both synergists that aid in this motion.
Muscle action that moves the axial skeleton work over a joint with an origin and insertion of the muscle on respective side. The insertion is on the bone deemed to move towards the origin during muscle contraction. Muscles are often present that engage in several actions of the joint; able to perform for example both flexion and extension of the forearm as in the biceps and triceps respectively.[11] This is not only to be able to revert actions of muscles, but also brings on stability of the actions though muscle coactivation.[15]
Agonist and antagonist muscles
The muscle performing an action is the agonist, while the muscle which contraction brings about an opposite action is the antagonist. For example, an extension of the lower arm is performed by the triceps as the agonist and the biceps as the antagonist (which contraction will perform flexion over the same joint). Muscles that work together to perform the same action are called synergists. In the above example synergists to the biceps can be the brachioradialis and the brachialis muscle.[11]
The skeletal muscles of the body typically come in seven different general shapes. This figure shows the human body with the major muscle groups labeled.
The gross anatomy of a muscle is the most important indicator of its role in the body. One particularly important aspect of gross anatomy of muscles is pennation or lack thereof. In most muscles, all the fibers are oriented in the same direction, running in a line from the origin to the insertion. In pennate muscles, the individual fibers are oriented at an angle relative to the line of action, attaching to the origin and insertion tendons at each end. Because the contracting fibers are pulling at an angle to the overall action of the muscle, the change in length is smaller, but this same orientation allows for more fibers (thus more force) in a muscle of a given size. Pennate muscles are usually found where their length change is less important than maximum force, such as the rectus femoris.[16]
Skeletal muscle is arranged in discrete muscles, an example of which is the biceps brachii. The tough, fibrous epimysium of skeletal muscle is both connected to and continuous with the tendons. In turn, the tendons connect to the periosteum layer surrounding the bones, permitting the transfer of force from the muscles to the skeleton. Together, these fibrous layers, along with tendons and ligaments, constitute the deep fascia of the body.[16]
Movement is not limited to only synovial joints, although they allow for most freedom. Muscles also run over symphysis, which allow for movement in for example the vertebral column by compression of the intervertebral discs. Additionally, synovial joints can be divided into different types, depending on their axis of movement.[17]
The body maintains its internal organization by means of membranes, sheaths, and other structures that separate compartments, called body cavities. The ventral cavity includes the thoracic and abdominopelvic cavities and their subdivisions. The dorsal cavity includes the cranial and spinal cavities.[11]
A serous membrane (also referred to as a serosa) is a thin membrane that covers the walls of organs in the thoracic and abdominal cavities. The serous membranes have two layers; parietal and visceral, surrounding a fluid filled space.[1] The visceral layer of the membrane covers the organ (the viscera), and the parietal layer lines the walls of the body cavity (pariet- refers to a cavity wall). Between the parietal and visceral layers is a very thin, fluid-filled serous space, or cavity.[1] For example, the pericardium is the serous cavity which surrounds the heart.[1]
In human anatomy, the arm refers to the upper limb in common usage, although academically the term specifically means the upper arm between the glenohumeral joint and the elbow joint. The distal part of the upper limb between the elbow and the radiocarpal joint is known as the forearm or "lower" arm, and the extremity beyond the wrist is the hand.
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes.
The scapula, also known as the shoulder blade, is the bone that connects the humerus with the clavicle. Like their connected bones, the scapulae are paired, with each scapula on either side of the body being roughly a mirror image of the other. The name derives from the Classical Latin word for trowel or small shovel, which it was thought to resemble.
The sacrum, in human anatomy, is a large, triangular bone at the base of the spine that forms by the fusing of the sacral vertebrae (S1–S5) between ages 18 and 30.
The brachialis is a muscle in the upper arm that flexes the elbow. It lies beneath the biceps brachii, and makes up part of the floor of the region known as the cubital fossa. It originates from the anterior aspect of the distal humerus; it inserts onto the tuberosity of the ulna. It is innervated by the musculocutaneous nerve, and commonly also receives additional innervation from the radial nerve. The brachialis is the prime mover of elbow flexion generating about 50% more power than the biceps.
In human anatomy, the fibularis longus is a superficial muscle in the lateral compartment of the leg. It acts to tilt the sole of the foot away from the midline of the body (eversion) and to extend the foot downward away from the body at the ankle.
In human anatomy, the metacarpal bones or metacarpus, also known as the "palm bones", are the appendicular bones that form the intermediate part of the hand between the phalanges (fingers) and the carpal bones, which articulate with the forearm. The metacarpal bones are homologous to the metatarsal bones in the foot.
The buccinator is a thin quadrilateral muscle occupying the interval between the maxilla and the mandible at the side of the face. It forms the anterior part of the cheek or the lateral wall of the oral cavity.
In human anatomy, the fibularis brevis is a muscle that lies underneath the fibularis longus within the lateral compartment of the leg. It acts to tilt the sole of the foot away from the midline of the body (eversion) and to extend the foot downward away from the body at the ankle.
The ilium is the uppermost and largest region of the coxal bone, and appears in most vertebrates including mammals and birds, but not bony fish. All reptiles have an ilium except snakes, although some snake species have a tiny bone which is considered to be an ilium.
Nomina Anatomica (NA) was the international standard on human anatomic terminology from 1895 until it was replaced by Terminologia Anatomica in 1998.
Terminologia Anatomica is the international standard for human anatomical terminology. It is developed by the Federative International Programme on Anatomical Terminology, a program of the International Federation of Associations of Anatomists (IFAA).
Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relative to the anatomical position of the body parts involved. Anatomists and others use a unified set of terms to describe most of the movements, although other, more specialized terms are necessary for describing unique movements such as those of the hands, feet, and eyes.
The following outline is provided as an overview of and topical guide to human anatomy:
The Terminologia Embryologica (TE) is a standardized list of words used in the description of human embryologic and fetal structures. It was produced by the Federative International Committee on Anatomical Terminology on behalf of the International Federation of Associations of Anatomists and posted on the Internet since 2010. It has been approved by the General Assembly of the IFAA during the seventeenth International Congress of Anatomy in Cape Town.
The Federative International Programme for Anatomical Terminology (FIPAT) is a group of experts who review, analyze, and discuss the terms of the morphological structures of the human body. It was created by the International Federation of Associations of Anatomists (IFAA) and was previously known as the Federative Committee on Anatomical Terminology (FCAT) and the Federative International Committee on Anatomical Terminology (FICAT).
An anatomical plane is a hypothetical plane used to transect the body, in order to describe the location of structures or the direction of movements. In human and non-human anatomy, three principal planes are used:
The pelvis is the lower part of the trunk, between the abdomen and the thighs, together with its embedded skeleton.
This article describes anatomical terminology that is used to describe the central and peripheral nervous systems - including the brain, brainstem, spinal cord, and nerves.
Many anatomical terms descriptive of bone are defined in anatomical terminology, and are often derived from Greek and Latin. Bone in the human body is categorized into long bone, short bone, flat bone, irregular bone and sesamoid bone.
References
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 This article incorporates text available under the CC BY 4.0 license.Betts, J Gordon; Desaix, Peter; Johnson, Eddie; Johnson, Jody E; Korol, Oksana; Kruse, Dean; Poe, Brandon; Wise, James; Womble, Mark D; Young, Kelly A (February 26, 2016). Anatomy & Physiology. Houston: OpenStax CNX. 1.6. Anatomical Terminology. ISBN978-1-93-816813-0. ID: 14fb4ad7-39a1-4eee-ab6e-3ef2482e3e22@8.24.
1 2 3 Drake, Richard L.; Vogl, Wayne; Tibbitts, Adam W.M. Mitchell (2005). Gray's anatomy for students. illustrations by Richard Richardson, Paul (Pbk.ed.). Philadelphia: Elsevier/Churchill Livingstone. ISBN978-0-443-06612-2.
↑ Federative Committee on Anatomical Terminology (2008). Terminologia Histologica – International Terms for Human Cytology and Histology. Cardiff: Lippincott Williams & Wilkins. ISBN978-0-7817-6610-4. OCLC63680504.
↑ Federative Committee on Anatomical Terminology (1998). Terminologia Anatomica – International Anatomical Terminology. Stuttgart: Thieme. ISBN978-3-13-115251-0. OCLC43947698.
↑ Losardo, Ricardo J. (2009). "Pan American Association of Anatomy: history and relevant regulations". Int J Morphol. 27 (4): 1345–52. ISSN0717-9367.
↑ Swartz, Mark H. (2010). Textbook of physical diagnosis: history and examination (6thed.). Philadelphia, PA: Saunders/Elsevier. ISBN978-1-4160-6203-5.
1 2 Moore, Keith L.; Dalley, Arthur F.; Agur, Anne M. R. (2010). Moore's Clinically Oriented Anatomy. Phildadelphia: Lippincott Williams & Wilkins. pp.29–35. ISBN978-1-60547-652-0.
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