Module 1. Anatomical Terminologies D. Ndhlovu -Chikwanda • OBJECTIVES • Define the anatomical position. • Use anatomical terminology to describe body directions, regions, and planes. • Anatomical Position • To accurately describe the various body parts and their locations, you use a common visual reference point • Reference point is known as anatomical position • Is a stance in which a person stands erect with feet together flat on the floor, arms at the sides ,palms face anteriorly with the thumbs pointed away from the body , face and eyes facing forward • Essential to learn the anatomical position because most of the directional terminology used in anatomy refers to the body in this position • The terms right and left always refer to those sides belonging to the person or cadaver being viewed • Body Regional terms • are the names of specific body areas • Knowledge of the external anatomy and landmarks of the body is important in performing a physical examination and many other clinical procedures • For the purpose of study there are two fundamental divisions of the body the axial and appendicular regions • axial region makes up the main axis of the body, consists of the head, neck, and trunk • The trunk is divided into the thorax (chest), abdomen, and pelvis • appendicular region of the body consists of the upper and lower limbs, also called appendages or extremities • Body cavities • are spaces within the body that house internal organs • spaces within the body that help protect, separate, and support internal organs • Bones, muscles, and ligaments separate the various body cavities from one another • Orientation and Directional Terms • Standard directional terms are used by medical personnel and anatomists to explain precisely where one body structure lies in relation to another • Most often used are the paired terms • superior/inferior, • anterior (ventral)/posterior (dorsal), • medial/lateral, • superficial/deep. • Superior (cranial) -Toward the head end or upper part of a structure or the body; above • Inferior (caudal) -Away from the head end or toward the lower part of a structure or the body; below • Anterior (ventral)* -Toward or at the front of the body; in front of • Posterior (dorsal)*- Toward or at the back of the body; behind • Medial- Toward or at the midline of the body; on the inner side of • Lateral -Away from the midline of the body; on the outer side of • Proximal- Closer to the origin of the body part or the point of attachment of a limb to the body trunk • Distal- Farther from the origin of a body part or the point of attachment of a limb to the body trunk • Superficial (external)- Toward or at the body surface • Deep (internal)- Away from the body surface; more internal • Ipsilateral- On the same side • Contralateral -On opposite sides • • • • • Ventral-Towards the front or belly Dorsal- Towards the back or spine Cephalic- Towards the head or superior end Rostral- Towards the forehead or nose Caudal-Towards the tail or inferior end Central means that a body part is situated at the center of the body or an organ. The central nervous system is located along the main axis of the body Peripheral means that a body part is situated away from the center of the body or an organ. • The peripheral nervous system is located outside the central nervous system. • • • • • • External • Toward the outside of a structure. • (Is typically used when describing relationships of individual organs.) • The visceral pleura is on the external surface of the lungs • Internal • Toward the inside of a structure. (Is typically used when describing relationships of individual organs.) • The mucosa forms the internal lining of the stomach • Body Anatomical Planes and Sections • In the study of anatomy, the body is often sectioned (cut) along a flat surface called a plane • Section- implies an actual cut or slice to reveal internal anatomy • Plane- implies an imaginary flat surface passing through the body • The most frequently used body planes are: • sagittal, frontal, and transverse planes • lie at right angles to one another • A frontal (coronal) plane extends vertically and divides the body into anterior and posterior parts • A transverse (horizontal) plane runs horizontally from right to left, dividing the body into superior and inferior parts • also called a cross sectional • Sagittal planes extends vertically and divide the body or an organ into right and left parts • Axes • three main axes running perpendicular to each other in three spatial coordinates • A longitudinal axis (vertical axis, cephalocaudal axis) of the body, which in the upright posture runs perpendicular to the base • A horizontal axis (transverse axis) running from left to right and perpendicular to the longitudinal axis • A sagittal axis running from front to back and perpendicular to both the other axes • Thoracic and Abdominal Cavity Membranes • A membrane is a thin pliable tissue that covers, lines, partitions, or connects structures • One example is a slippery double-layered membrane called a serous membrane • It covers the viscera within the thoracic and abdominal cavities and also lines the walls of the thorax and abdomen • The parts of a serous membrane are • (1) the parietal layer a thin epithelium that lines the walls of the cavities, (2) the visceral layer , a thin epithelium that covers and adheres to the viscera within the cavities. • Parietal and visceral membranes are continuous with one another, they form a serous sac. • Small amount of lubricating fluid (serous fluid) within the serous cavity (inside the sac) reduces friction between the two layers • Allows the viscera to slide during movements such as :• Pumping of the heart • Inflation and deflation of lungs when breathing in and out • The serous membrane associated with the lungs is called the pleura • visceral pleura clings to the surface of the lungs • The parietal pleura lines the chest wall and covers the superior surface of the diaphragm • In between is the pleural cavity, filled with a small volume of lubricating fluid(serous fluid) • The serous membrane of the heart is the pericardium • Visceral pericardium covers the surface of the heart • The parietal pericardium lines the fibrous pericardium that surrounds the heart. • Between them is the pericardial cavity, which contains a small amount of lubricating fluid. • The peritoneum is the serous membrane of the abdominal cavity • The visceral peritoneum covers the abdominal viscera, and the parietal peritoneum lines the abdominal wall and covers the inferior surface of the diaphragm. • Between them is the peritoneal cavity, which contains a small amount of lubricating fluid. • Most abdominal organs are surrounded by the peritoneal cavity and are referred to as intraperitoneal • stomach, spleen, liver, gallbladder, jejunum and ileum of the small intestine, and the cecum, appendix, and tranverse colon of the large intestine • some are located between the parietal peritoneum and the posterior abdominal wall • Such organs are said to be retroperitoneal • The kidneys, adrenal glands, pancreas, duodenum of the small intestine, ascending and descending colons of the large intestine, and the abdominal aorta and inferior vena cava are retroperitoneal organs. ABDOMINOPELVIC REGIONS AND QUADRANTS • To describe the location of the many abdominal and pelvic organs more easily, anatomists and clinicians use two methods of dividing the abdominopelvic cavity into smaller areas • First method, two transverse and two vertical lines, partition the cavity into nine abdominopelvic regions • The superior horizontal line, the subcostal line , passes across the lowest level of the 10th costal cartilages • Others use the transpyloric line located halfway between the supra sternal notch of the manubrium and upper border of the pubic symphysis at the level of the 1st lumbar vertebrae. • the inferior horizontal line, the transtubercular line, passes across the superior margins of the iliac crests of the right and left hip bones • Two vertical lines, the left and right midclavicular lines, are drawn through the midpoints of the clavicles(collar bones), just medial to the nipples • The four lines divide the abdominopelvic cavity into a larger middle section and smaller left and right sections. • The names of the nine abdominopelvic regions are:• right hypochondriac, epigastric, left hypochondriac, right lumbar, umbilical, left lumbar, right inguinal (iliac),hypogastric (pubic), and left inguinal (iliac • The second method is simpler and divides the abdominopelvic cavity into quadrants • a transverse line, the transumbilical line, and a midsagittal line, the median line, are passed through the umbilicus • The names of the abdominopelvic quadrants are :• right upper quadrant (RUQ), left upper quadrant(LUQ), right lower quadrant (RLQ), and left lower quadrant (LLQ) • The nine-region division is more widely used for anatomical studies to determine organ location; • quadrants are more commonly used by clinicians for describing the site of abdominopelvic pain, tumor, injury, or other abnormality Noninvasive Diagnostic Techniques • Noninvasive diagnostic techniques are commonly used by health-care professionals and students to assess certain aspects of body structure and function • noninvasive diagnostic technique is one that does not involve insertion of an instrument or device through the skin or into a body opening • 1.Inspection, the first noninvasive diagnostic technique, the examiner observes the body for any changes that deviate from normal • E.g. a physician may examine the mouth cavity for evidence of disease • 2. In palpation the examiner feels body surfaces with the hands. • An example is palpating the neck to detect enlarged or tender lymph nodes. • 3. In auscultation the examiner listens to body sounds to evaluate the functioning of certain organs, often using a stethoscope to amplify the sounds. • An example is auscultation of the lungs during breathing to check for crackling sounds associated with abnormal fluid accumulation in the air spaces of the lungs. • 4.In percussion the examiner taps on the body surface with the fingertips and listens to the resulting echo • For example, percussion may reveal the abnormal presence of fluid in the lungs or air in the intestines. • It is also used to reveal the size, consistency, and position of an underlying structure • Anatomical terms of Movement • • • • • • • • • Used to describe the actions of muscles on the skeleton Muscles contract to produce movement at joints These movements can be described using the following terminologies Flexion This movement occurs in the sagittal plane A movement that decreases the angle between two body parts Extension Also occurs in the sagittal plan Refers to a movement that increases the angle between two body parts • • • • • • • • • • Abduction Refers to movement of a body part away from the midline or midsagital Adduction Refers to movement towards the midline Medial Rotation(Internal rotation) Describes movement of the limb around their long axis Is a rotational movement towards the midline Lateral rotation(External rotation) Also movement of the limb around it’s long axis Is a rotating movement away from the midline Elevation Refer to movement in superior direction Depression Refer to movement in an inferior direction Pronation and Supination refer to movements of the radius around the ulna Supination occurs when the forearm rotates laterally so that the palm faces anteriorly • Pronation occurs when the forearm rotates medially so that the palm faces posteriorly • Supine also means lying flat on the back and face up and prone also means lying flat on the front and face down. • • • • • • • • Circumduction • a complex movement that combines flexion, abduction, extension, and adduction in succession • Opposition • action by which you move your thumb across the palm enabling it to touch the tips of the other fingers on the same hand • Inversion and Eversion • special movements of the foot • To invert the foot ,turn the sole medially; • To evert the foot, turn the sole laterally • Dorsiflexion and Plantar Flexion • Describe movement at the ankle • Dorsiflexion is lifting the foot so that its superior surface approaches the shin • Plantar flexion is depressing the foot or elevating the heel (pointing the toes) • Dorsiflexion of the foot corresponds to hand extension at the wrist • Plantar flexion corresponds to hand flexion • Protraction and Retraction • Protraction nonangular movements in the anterior direction or movement of a bone anteriorly (forward) in the horizontal plane • Retraction nonangular movements in the posterior direction
