Anatomy Nomenclautre PDF

INTRODUCTION ANATOMIC NOMENCLATURE Anatomy – science that deals with the form and Practical Names structure of all organisms. “to cut apart” - Function (i.e. adductor muscle of...

INTRODUCTION ANATOMIC NOMENCLATURE Anatomy – science that deals with the form and Practical Names structure of all organisms. “to cut apart” - Function (i.e. adductor muscle of the thigh) BRANCHES OF ANATOMY - Position relative to other similar structure (i.e. superficial inguinal ring) Gross (macroscopic) Anatomy - Location (i.e. infraorbital foramen) - study of the form and relations (relative - Appearance or form (i.e. greater curvature of positions) of the structures of the body that the stomach) can be seen with the unaided eye Eponymous names (NOT USUALLY USED) Comparative anatomy - Relate the structure to a person, usually the - study of the structures of various species of person who first described the structure (e.g. animals, with particular emphasis on those canal of Schlemm) characteristics that aid in classification - Because eponyms are useless from a practical standpoint, the Nomina Anatomica Embryology Veterinaria discourages their use - study of developmental anatomy, covering the period from conception to birth Descriptive Terms in Anatomy Histology (microscopic anatomy)  Cranial - towards the head (i.e. the shoulder - study of tissues and cells that can be seen is cranial to the hip) only with the aid of a microscope  Caudal - towards the tail (i.e. the rump is Ultrastructural cytology caudal to the loin)  Rostral and caudal are directional terms used - deals with portions of cells and tissues as they in reference to features of the head to mean are visualized with the aid of the electron toward the nose (rostral) or toward the tail microscope (caudal) - Fine structure - a term frequently used in  Median plane - an imaginary plane passing reference to structures seen in electron through the body so as to divide the body into micrographs equal right and left halves Systemic anatomy  Sagittal plane - any plane parallel to the median plane (DOES NOT DIVIDE THE - study of anatomy through a systematic BODY INTO EQUAL PARTS) approach o PARALLEL – do not intersect but of the same direction -ology (branch of knowledge or science) - suffix added to the root word referring to the system to name  Transverse plane - at right angles to the the study median plane and divides the body into cranial and caudal segments Nomenclature for Systematic Anatomy  Horizontal plane - at right angles to both the median plane and transverse planes Name of System Study Chief Structure o Divides the body into dorsal (upper) Skeletal and ventral (lower) segments Osteology Bones o ALSO KNOWN AS DORSAL System Articular PLANE Arthrology Joints System  Medial - adjective meaning close to or toward Muscular the median plane Myology Muscles System Digestive Stomach and o ie. the heart is medial to the lungs; it Splanchnology is closer to the median plane than System intestines Respiratory are the lungs Splanchnology Lungs and airways System  Lateral - means away from the median plane Kidneys and urinary o ie. the ribs are lateral to the lungs, Urinary System Splanchnology bladder that is farther from the median plane Reproductive System Splanchnology Ovaries and testes  Dorsal - toward or beyond the backbone or Endocrine vertebral column Endocrinology Ductless glands System o Dorsum - the noun referring to the Nervous Brain, spinal cord, and dorsal portion or back Neurology System nerves  Ventral - away from the vertebral column or Circulatory Cardiology Heart and vessels toward the midabdominal wall System Sensory Esthesiology Eyes and ear System   Deep and internal - indicate proximity to the  Rotation - describes an essentially circular center of an anatomical structure movement of a part (rather than a joint) (MADALOM) around its long axis, as when the head of the  Superficial and external - refer to proximity to humerus rotates in the glenoid cavity of the the surface of the body (MANABAW) scapula  Proximal - relatively close to a given part, o The direction of the rotation is usually the vertebral column, body or center described by the direction of of gravity. Generally used in reference to an movement of the cranial or lateral extremity of limb (MALAPIT) surface of the part being moved  Distal - farther from the vertebral column, and  Circumduction - describes a combined generally used in reference to portions of an movement, involving BOTH flexion/extension extremity (MALAYO) and abduction/adduction.  -ad - suffix used to form an adverb from any o The resulting movement essentially of the named directional terms, indicating describes a circula movement in the direction of or toward  Prone - refers to a position in which the dorsal o e.g. dorsad, ventrad, caudad, aspect of the body or any extremity is craniad uppermost (GAHAPA)  Palmar - refers to the flexor or caudal surface o Pronation - refers to the act of when describing the thoracic limb (forelimb) turning toward a prone position (FRONT LEGS/ LIMBS) (GINAPA-HAPA)  Plantar - refers to the caudal surface when  Supine - refers to the position in which the describing the pelvic limb (hindlimb) (BACK ventral aspect of the body or palmar or plantar LEGS/ LIMBS) aspect of an extremity is uppermost  Axial - used in reference to the digits to mean (GAKAYA) toward the functional axis of the limb o Supination - refers to the act of  Abaxial - used in reference to the digits to turning toward a supine position mean away the functional axis of the limb (GINAPA-KAYA) Terms describing anatomical movements  Flexion - decreases the angle of a joint, as MICROSCOPIC ANATOMY: ANIMAL CELLS AND when the elbow or finger is bent TISSUES  Extension - increases the angle of a joint, as  Cells - smallest, basic unit of life that is when the elbow or finger is straightened responsible for all of life's processes  Hyperextension (dorsiflexion) - extends a joint beyond a linear or straight configuration, so Three main parts: that the angle of the joint is extended beyond Cytoplasm 180 degrees (USUALLY HAPPENS IN Nucleus FRACTURES OR BENT BODY PART) Cell membrane  Adduction - moves a body part toward the  Tissue - group of specialized cells median plane, as when a limb is tucked under  Connective tissue - made up by cells that the body specialize in holding structures  Abduction - moves a body part away from the  Organs - group of tissues that work together median plane, as when a limb is pulled to the for overall function side  Organ system - group of organs that  Protraction - moves a structure cranially or participate in a common enterprise rostrally, or moves it away from the central body, a when the tongue is projected from the CELL ➡ TISSUE ➡ ORGAN ➡ ORGAN mouth SYSTEM  Retraction - moves a structure back toward the body, as when the tongue is replaced in Primary types of tissues the mouth  Elevation - moves a structure dorsally, as  Epithelial tissues - cover the surface of the when the shoulder is shrugged or the eyelid is body, line body cavities and form glands opened  Connective tissues - support and bind other  Depression - moves a structure ventrally, as tissues together and from which the formed when the eyelid is closed elements of the blood are derived (bone  Inversion - rotates the pelvic limb so that the marrow) plantar/caudal surface faces medially (similar  Muscle tissues - specialize in contracting to supination)  Nervous tissues - conduct impulses from one  Eversion - rotates the pelvic limb so that the part of the body to another plantar/caudal surface faces laterally or caudally (similar to pronation) Epithelial Tissues o In ruminants, stratified squamous epithelium also lines the forestomach - classified as simple (composed of single- o Thickest and toughest of the epithelia, layer) or stratified (many layered) consisting of many layers of cells - further subdivided according to the shape of o Layers (from deep to superficial): the individual cells within it  Basal layer (stratum basale) - contains o Squamous - platelike the actively growing and multiplying cells o Cuboidal - cubic o Cells are somewhat cuboidal, o Columnar - cylindrical but as they are pushed toward o Pseudostratified columnar – (varies in the surface, away from the length) blood supply of the underlying tissues, they become flattened, tough and lifeless Simple squamous epithelium o This layer of cornified o Consists of thin, platelike cells (keratinized) dead cells o Much expanded in two directions but have becomes very thick in areas little thickness subjected to friction o The edges are joined somewhat like a mosaic  Parabasal layer (stratum spinosum) tile covering a floor  Intermediate layer (stratum granulosum) o A layer of simple squamous epithelium has  Superficial layer (stratum corneum) little tensile strength and is found only as a covering layer for stronger tissues 2. Stratified columnar epithelium o Found where a smooth surface is required to o Composed of more than one layer of reduce friction columnar cells and is found lining part of the o e.g. covering of viscera and the linings of pharynx and salivary ducts body cavities and blood vessels 3. Transitional epithelium (CAN UNDERGO CHANGES IN STRUCTURE) o Lines the portions of the urinary system that Cuboidal epithelial cells are subjected to stretching (i.e. urinary o Approximately equal in all dimensions bladder, ureters) o Found in some ducts and in passageways in o Can pile up many cells thick when the bladder the kidneys is small and empty and stretch out to a single layer when completely filled Columnar epithelial o Cylindrical o Arranged somewhat like the cells in a honeycomb o Some have whiplike projections called cilia extending from the free extremity Pseudostratified columnar epithelium o Composed of columnar cells o Vary in length, giving the appearance of more than one layer or stratum o Found in the upper respiratory tract, where the lining cells are ciliated Stratified epithelium (MANY LAYERS) - Consists of more than one layer of epithelial cells and includes stratified squamous, stratified columnar, and transitional epithelia 1. Stratified squamous epithelium o Forms the outer layer of the skin and the lining of the first part of the digestive tract as far as the stomach Epithelial Tissues  Glandular epithelial cells are specialized for Compound glands secretion or excretion O Secretion - release from the gland cells of a substance that has been synthesized by the cell and that usually affects other cells in other parts of the body (ex. hormones and enzymes ) o Excretion - expulsion of waste products (ex. urine and sweat)  Glands: o Endocrine - glands without ducts, which empty their secretory o Subdivided grossly into globes, which are products directly into the further subdivided into globules bloodstream o The connective tissue partitions, septa, are  Pituitary, thyroid, classified as interlobar septa if they separate parathyroid, thymus, lobes and interlobular septa if they separate adrenal glands globules o Exocrine - glands that empty their secretory products on an epithelial surface, usually by means of ducts Gland classification based on the manner in which (WITH DUCT/S) their cells elaborate secretion  Sweat glands, lacrimal glands, salivary glands, mammary glands, digestive glands in the stomach, pancreas and intestines  Endocrine glands (DUCTLESS) o Produce hormones o Hormones carried to all parts of the body by the blood constitute the humoral control of the body o Humoral control and nervous control are the two mechanisms maintaining homeokinesis, also called  Merocrine gland (NO LOSS/DAMAGE) homeostasis o Pass their secretory products  Homeostasis - a state of through the cell wall without any balance among all the body appreciable loss of cytoplasm or systems needed for the noticeable damage to the cell body to survive and membrane function correctly o Constitute the endocrine system  Holocrine gland (LOSS/DAMAGE IN PORTIONS OF CELLS)  Morphologic classification of glands o Least common type o After the cells fills with secretory material, the entire holocrine gland o Simple - if the duct that not branch or has no duct at all cell discharges to the lumen of the  e.g. sweat glands, gastric gland to constitute the secretion o Sebaceous glands associated with glands, intestinal crypts, uterine glands hair follicles of the skin are the most o Compound - if it does not branch common holocrine gland  e.g. salivary glands, pancreas  Apocrine gland (LOSS/DAMAGE OF ENTIRE o Tubular - if the secretory portion form a CELLS) tubelike structure o An intermediate form of secretion in o Alveolar or acinar - if the secretory which a small amount of cytoplasm portion resembles a grape or hollow ball and cell membrane is lost with the o Tubuloalveolar gland - combination of secretion tubular and alveolar secretory structures o Prostate and some sweat glands Connective Tissues o The dermis of the skin, which may be tanned to make leather, consists  Serve to connect other tissues of dense irregular connective tissue  They give form and strength to many organs o This forms a strong covering that and often provide protection and leverage resists tearing and yet is flexible  Include: enough to move with the surface of o Elastic tissue the body o Collagenous (white fibrous) tissue o Reticular (netlike) tissue o Adipose (fat) tissue o Cartilage o Bone  Elastic tissue (ABLE TO STRETCH) o Contains kinked fibers that tend to regain their original shape after  Areolar (loose) connective tissue being stretched o Found throughout the body wherever o Found in the ligamentum nuchae, protective cushioning and flexibility are a strong band that helps to support needed the head, particularly in horses and o i.e. blood vessels are surrounded by a cattle sheath of areolar connective tissue, o Found in the abdominal tunic, in the which permits the vessels to move and ligamenta flava of the spinal canal, yet protects them in elastic arteries, and mixed with other tissues wherever elasticity is needed  Collagenous (white fibrous) tissue o Found throughout the body in various forms o Individual cells (fibroblasts) produce long proteinaceous fibers of collagen, which have remarkable  Reticular connective tissue (looks like tensile strength branches and leaves) o These fibers may be arranged in o Consists of fine fibrils and cells regular repeating units, or laid down o Makes up part of the framework of in a more random, irregular endocrine and lymphatic organs arrangement  Dense regular connective tissue - the fibers are arranged in parallel bundles, forming cords or bands of considerable strength o These are the tendons, which connect muscles to bones and the ligaments which connect bones to  Adipose (fat) tissue bones o Forms when connective tissue cells called adipocytes store fat as inclusions within the cytoplasm of the cell o As more fat is stored, the cell eventually becomes so filled with fat that the nucleus is pushed to one side of the cell, which, as a result, becomes spherical  Dense irregular connective tissue - arranged in a thick mat, with fibers running in all directions   Bone o Produced by bone-forming cells called osteoblasts o These cells produce osteoid tissue, which later becomes calcified to form bone  Cancellous or spongy bone - sponge-like network formed when bone is arranged in the form of  White fat - found in most animal body, spicules (small spikes) and flat although may have a yellow tinge in plates horses and some breeds of dairy cattle because of carotenoids in the feed  Compact bone - bone is laid down  Brown fat - may be found domestic in the form of laminated cylinders mammals, hibernating mammals, (Haversian or osteonal systems) rodents, and human infants closely packed together  Generates heat to protect young mammals and hibernating mammals from extreme cold (INSULATION)  Cartilage (CONNECTS BONE TO ANOTHER BONE) o A special type of connective tissue that is firmer than fibrous tissue but not as hard  Blood as bone o Consists of a fluid matrix (liquid portion), o The nature of cartilage is due to the the plasma, a variety of cells, proteins, structure of the intercellular material monosaccharides (simple sugars), found between the chondrocytes products of fat degradation, and other (cartilage cells) circulating nutrients, wastes, electrolytes, o The three types of cartilage: hyaline, and chemical intermediates of cellular elastic and fibrous metabolism o It is sometimes considered to be a  Hyaline cartilage connective tissue because of the origin of o Glasslike covering of bones within some of its components joints o Forms a smooth surface that  Red blood cells | erythrocytes reduces friction, so that one bone o In most domestic mammals they are non- easily glides over the another nucleated biconcave discs that contain o The actively growing areas near the the protein haemoglobin ends of long bones also consist of o Main function is to carry haemoglobin hyaline cartilage o Hemoglobin in turn has the primary  Elastic cartilage function of carrying oxygen from the o Consists of a mixture of cartilage lungs to all tissues of the animal substance and elastic fibers o Anemia is a reduction in the o This type of cartilage gives shape concentration of functional RBCs in the and rigidity to the external ear blood  Fibrocartilage o Consists of a mixture of cartilage and collagenous fibers, which forms a semi  White cells | leukocytes elastic cushion of great strength o One of the body's first line of defense o The intervertebral discs between the against infection bodies of adjacent vertebrae are o Agranulocytes (WITHOUT composed of fibrocartilage GRANULES)  Monocytes - large cells that engulf and destroy foreign particles  Lymphocytes - smaller and are associated with immune responses o Granulocytes | polymorphonuclear lymphocytes (WITH GRANULES) –  have 3 types that are described  Striated muscle - muscle according to their affinity for different cells that consist of fibers stains that show characteristic  Neutrophils - stain cross-striations under the indifferently (NO STAIN) microscope  Basophils - have dark- staining granules when stained with common blood 1. Skeletal stains (BLUE STAIN) o Each muscle cell must have its own nerve  T Eosinophils - have red- supply, and when stimulated, the whole fiber staining granules contracts (all or nothing)  Platelets (thrombocytes) - o This is the all-or-none law of muscle small, irregularly shaped contraction cellular fragments that are o The force of contraction depends on the state associated with the clotting on the state of the fiber at any moment of the blood o Striated skeletal muscle tissue plus some connective tissue makes up the flesh of meat- producing animals 2. Smooth muscle cells o Are spindle-shaped cells that contain one centrally located nucleus per cell o Found in the walls of the digestive tract, in the walls of blood vessels, and in the walls of urinary and reproductive organs o These cells contract more slowly than skeletal muscle and in response to a variety of stimuli, although they are not under voluntary control  Plasma (IN UNCLOTTED BLOOD) o Is the fluid part of the unclotted blood 3. Cardiac muscle o Particularly useful as a substitute for o Also known as involuntary striated muscle blood in transfusions because the because it is not usually under conscious proteins in it give it the same osmotic control, yet it does have cross-striations pressure as blood o The heart muscle is composed of a complex o Plasma, therefore, will not escape from branched arrangement of cardiac muscle blood vessels as readily as a salt cells solution o Modified muscle cells called Purkinje fibers conduct impulses within the heart, much as  Serum (IN CLOTTED BLOOD) nerve fibers do in other parts of the body o Is the supernatant fluid that remains after a clot forms and incorporates the cellular components of blood o It is similar to plasma but lacks most of the clotting factors o Sometimes administered for prevention and treatment of diseases because it contains the antibody fractions of the blood Nervous Tissues  Neuron - the essential cell of nervous tissue o Consists of a nerve cell body and two or more nerve processes (nerve fibers) o Axons - the processes that conduct impulses away from the cell body o Dendrites - the processes that conduct Muscle Tissues impulses toward the cell body  Three types of muscle tissue: o Tracts - bundles of axons in the spinal 1. Skeletal - striated muscle cord 2. Smooth o Nerves - bundles of axons in the 3. Cardiac - striated muscle periphery  o Myelin sheath - a specialized wrapping rectum) and all of the internal created by supportive cells called portions of the urogenital system not Schwann cells in nerves and found in the abdominal cavity oligodendrocytes within the brain and o Peritoneum - the serous membrane spinal cord that surrounds the abdominal  Covers a nerve fiber viscera and part of the pelvic viscera o Neuroglia - special connective tissues of  Visceral serous membrane - part of the nervous tissue and are found only in the serous membrane covering the viscus central nervous system (CNS) o Visceral pericardium o Visceral pleura o Visceral peritoneum  Parietal serous membrane - serous membrane lining a body cavity o Parietal pericardium o Parietal pleura o Parietal peritoneum The General Plan of the Animal Body  The body (with the exception of some of the internal organs) exhibits bilateral symmetry o Bilateral symmetry - a condition in which the right and left sides of an item (e.g., a shape or an animal) are mirror images of one another  The right and left sides of the body are mirror images of each other  Similar right and left structures are called paired structures  Most unpaired structures are on or near the median plane, and of course, only one of each unpaired structure exists in any given animal o i.e. tongue, trachea, vertebral column, and heart  Mesothelium - the simple squamous epithelium lining various body cavities  The diaphragm divides the embryonic body cavity into a thoracic cavity and the abdominopelvic cavity  Thoracic cavity o Pericardial sac - surrounds the heart o Pleural sac (2) - surrounds the two lungs o These sacs are formed by a serous membrane, the pleura, a layer of simple squamous epithelium with underlying connective tissue, moistened with the small amount of fluid within the cavity of the sac  Abdominopelvic cavity - divided into abdominal and pelvic cavity o Abdominal cavity - contains the kidneys, most of the digestive organs and a variable amount of the internal reproductive organs in both sexes o Pelvic cavity - contains the terminal part of the digestive system (the  OSTEOLOGY  Epiphyseal cartilage or disk (physis) Osteology - A layer of hyaline cartilage within the - study of bones metaphysis of an immature bone that - the skeletal system includes the bones, and separates the diaphysis from the the cartilage, ligaments, and connective epiphysis tissues that hold everything together - This is the only area in which a bone can lengthen Functions of Bones  Protection of vital organs  Articular cartilage  Giving rigidity and form to the body - Thin layer of hyaline cartilage that covers  Acting as levers the articular (joint) surface of a bone  Storing minerals  Periosteum  Forming the cellular elements of blood - Fibrous membrane that covers the surface of a bone except where articular Terminology cartilage is located  Osteoblasts (bone-producing cells) - Responsible for increases in the diameter of bones  Endosteum - Fibrous membrane that lines the marrow cavity and osteonal canals (osteons) of a bone  Osteoclasts (bone-destroying cells)  Projections (NAKA-UMBOK) and depressions (NAKAPALALIM) - Articular - form an integral part of the joint and covered with articular cartilage - Non articular - exist outside of joints  Compact (dense or cortical) bone - The hard layer that constitutes the Classification of Bones exterior of most bones and forms almost the entire shaft of long bones 1. Location - Axial skeleton - includes the skull,  Cancellous (spongy) bone vertebral column, ribs, and sternum - Composed of spicules arranged to form - Appendicular skeleton - includes the a porous network bones of the limbs - The spaces are usually filled with marrow 2. Shape  Medullary cavity (marrow cavity) - The space surrounded by the cortex of a  Long bones long bone - Greater in one dimension than any other - Red marrow - found in young animals - Found in the limbs, where they provide - Yellow marrow - replaces the red an attachment site for limb muscles and marrow as the animal ages levers for movement - They have identifiable structural regions  Epiphysis - Metaphyses - are the - refers to either end of a long bone morphologically specialized - The end closest to the body is the proximal and distal ends of proximal epiphysis the bones - The end farthest from the body if the - Diaphysis - is the shaft of the distal epiphysis bone - Epiphyses - regions between  Diaphysis the metaphyses - The cylindrical shaft of a long bone o In a growing animal, the between the two epiphysis epiphyses are separated from the metaphyses and  Metaphysis the diaphysis by - The flared area adjacent to the epiphysis cartilaginous epiphyseal of a mature bone growth plates, which are  active sites of endochondral bone formation and bone elongation o After growth is complete, the epiphyseal plates ossify or “close”, and the three regions of the long bones blend smoothly together  Short bones - Found only in the carpus and tarsus (PALMS) - Cuboid, or approximately equal in all dimensions - There is no single marrow cavity but the interior is composed of spongy bone filled with marrow spaces - The exterior is formed by a thin layer of compact bone - Absorb concussion, and they are found in complex joints such as the carpus (the “knee” of the thoracic limb) and tarsus 3. Cartilage (hock), where a variety of movements as well as absorption of shock occur. - Comprises a relatively small part of the skeleton  Flat (squamous) bones - Also composed of cells surrounded by an - Relatively thin and expanded in two intercellular matrix dimensions - Cartilage is avascular, thus cartilage - They consist of two plates of compact responds poorly to injury and does not bone, the lamina externa and lamina heal well interna, separated by a spongy material o Avascular - Not associated called diploë with or supplied by blood - Found in most regions of the skull and in vessels. the ribs - These bones generally serve a  Hyaline cartilage (REDUCE FRICTION) protective or reinforcing function - Lines the surface of synovial joints and is - Skull, scapula and ribs, pelvis characterized by a matrix possessing abundant natural lubricants  Sesamoid bones - Also forms the cartilaginous portion of the - Resembles a sesame seed, although ribs, comprises most of the laryngeal many sesamoid bones of domestic cartilages, and serves as the anlage for animals have decidedly un-seedlike long bone development shapes - The most commonly found form of - Occur along the course of tendons to cartilage in the skeleton reduce friction, increase leverage, or change the direction of pull  Fibrocartilage - The patella is the largest sesamoid bone - Particularly durable and resilient, possessing a matrix comprised of  Irregular bones extensive bundles of collagenous fibers - Unpaired bones on the median plane - Is more restricted in its distribution that - Includes the bones of the vertebral hyaline cartilage column, the bones of the pelvis, and the - Found in most symphyses (pelvic, bones of the skull that are not flat intervertebral) and in the menisci of the - These bones do not fit well into any other stifle and temporomandibular joints descriptive classification  Elastic cartilage  Pneumatic bones - Possesses a matrix containing large - Contain air spaces or sinuses that amounts of elastic fibers communicate with the atmosphere - The resulting cartilage has a great deal of - The frontal bones and maxillary bones of flexibility, but nonetheless considerable the skull are examples of this type of strength bone among mammals - Elastic cartilage forms the skeleton of the - May avian bones are “pneumatized” as pinna, the external nose and the well epiglottis 4. Articulation (joints) provides lubrication for the joint’s movement  Fibrous joints (synarthrosis; pl: synarthroses) - Types - can be classified according to - Capable of minimal to no movement the amount of mobility afforded by the - Main goal of synarthrosis is to hold the joint bones together - Ball-and-socket (SHOULDER JOINT) ○ Sutures - such as those found - Ginglymus (hinge) among the flat bones of the cranium (SHOULDER JOINT) ○ Syndesmoses - considerable amount of connective tissue 5. Markings on Bones intervenes between the two bones in question (e.g. the tibiofibular joint,  Canal - a tunnel through one or more the attachment of hyoid apparatus to bones (e.g. vertebral canal) the skull)  Condyle - a large articular prominence (e.g. occipital condyles of the skull and ○ Gomphoses - the specialized joints the condyles of the humerus, femur and that hold the teeth in their alveoli tibia)  Cotyloid cavity - a deep articular  Cartilaginous joints (amphiarthrosis; pl: depression (e.g. acetabulum of the hip amphiarthroses) joint) - Permit only limited motion  Crest - a prominent border or ridge (e.g. - Mainly stretching or compression crest of the hipbone) ○ Hyaline cartilage joints - are  Epicondyle - a prominence just proximal mainly characteristic of growing to a condyle (e.g. lateral epicondyle of bone and are lost as the animal the humerus or femur) matures  Facet - a smooth, flat surface (e.g. ○ Fibrocartilaginous joints - features articular facet of a thoracic vertebra for attachment to a rib) of the mature skeleton  They are found in the pelvic ○ Articular facets are covered with symphysis, mandibular hyaline cartilage symphysis, and between the  Fissure - a narrow, cleft-like opening sternebrae and vertebral bodies between adjacent bones  These joints occasionally ossify  Foramen - an opening through a bone with advanced age (e.g. infraorbital foramen, obturator foramen, foramen magnum)  Fossa - a small hollow (e.g. mandibular  Synovial joints (diarthrosis; pl: fossa, olecranon, and radial fossa of the diarthroses, “true joints”) humerus) - Permit only relatively wide range of  Fovea - a shallow, nonarticular motion depression (e.g. fovea capitis on the - The range of motion at a joint may be in head of the femur) a single plane (e.g. elbow), or in multiple  Groove - a long, narrow furrow directions (e.g. hip) accommodating a vessel, nerve or - Motions that can take place at joints, tendon (e.g. grooves on the distal end of depending on the form of the joint, the radius) include flexion, extension,  Head - a rounded articular process (e.g. hyperextension, abduction, adduction, head of the femur or humerus) rotation and circumduction  Line - a ridge less prominent than a crest  Meatus - a tube-like canal through a - Components: bone (e.g. external auditory meatus) - Two bones - the ends of which are covered by hyaline  Notch - a depression at the edge of a cartilage bone (e.g. semilunar notch of the ulna, - A joint cavity that lies between popliteal notch of the tibia) the two apposing bones  Process - any prominent, roughened - A joint capsule that entirely projection from a bone (e.g. crest, spine, surrounds the joint cavity, trochanter, tubercle, tuberosity) extending both proximal and  Spine - a sharp, slender process (e.g. distal to it spine of a vertebra, spine of a scapula  The outer, fibrous layer is  Trochanter - a large, blunt process a protective, strengthening found only on the femur (e.g. greater structure trochanter of the femur)  The inner, synovial layer  Trochlea - a pulley shaped structure secretes the viscous and (e.g. trochlea of the femur) slick synovial fluid, which   Tubercle - a small, rounded process  The upper and lower jaws are of the same (e.g. greater tubercle of the humerus) length, and the dental arcades meet evenly  Tuberosity or tuber - a large, usually along their full extent roughened process (e.g. ischial e.g. beagles, Alaskan malamutes, huskies, Labrador tuberosity) retrievers DOLICHOCEPHALIC Form departs from the mesaticephalic form by being longer and more narrow  The facial and cranial regions are usually of nearly the same length and width  The cranium is narrow and low  Because the cranial region is not as high as in mesaticephalic breeds, the stop is less pronounced  The eyes are smaller and more closely spaced than in mesaticephalic breeds, but they still fit well within their orbits, and may even be recessed into the orbit to some degree Axial Skeleton  The lower jaw is sometimes notably shorter  Includes bones on or attached to the midline than the upper jaw, a condition referred to as (axis) of the body and comprise the skull, brachygnathism. Most of the time, the upper vertebral column, sternum, and ribs and lower dental arcades meet fairly evenly e.g. greyhounds, Afghan hounds and salukis The Head  Morphologic Forms BRACHYCEPHALIC MESATICEPHALIC Departs from the generalized mesaticephalic  The least changed from the ancestral form form in that it is shorter and  Proportions of the head are in concert with wider each other, and overall form of the head forms  The facial region is considerably shorter than a harmonious whole the cranial region. The cranium is sometimes  The facial and cranial regions are usually high and rounded; as a result of the height of nearly the same length and width the cranium, the stop is usually very o The cranium is wide and usually roughly pronounced square-shaped  The eyes are large and often widely spaced. o The junction of the facial and cranial They usually protrude considerably from their regions is characterized by a notable orbits elevation from the level of the face to the  The lower jaw is usually longer than the upper higher level of the cranium. This point is jaw, a condition referred to as prognathism called the stop e.g. English bulldogs, boston terriers, Pekingese and  The eyes are moderately widely spaced, and Chihuahuas fit well within their orbits  THE SKULL AND VERTEBRAE  Lacrimal fossa - the depression in the medial margins of the orbit. THE SKULL o It collects tears and sends them through  The part of the skeleton within the head is the the lacrimal canal which opens into the skull nasal cavity  Protects the brain, supports many of the sense organs, and forms passages for entry  Infraorbital foramen - the rostral opening of to the digestive and respiratory systems the infraorbital canal, located in the maxillary  Consists of the cranial part (braincase), which bone surrounds the brain, and the facial part  The skull is a very complex structure made  Occipital condyles - the paired structures mostly of flat bones lateral to the foramen magnum that  Except for the mandible that is attached via a articulates with the first cervical vertebra movable joint, the bones of the skull are (atlas) connected by interlocking joints called sutures.  Paracondylar (jugular) process - the ventral o Suture joints are characterized by a projection near the occipital condyles saw-toothed or serrated appearance that keeps the bones attached, but  External acoustic meatus - the large allows the cranium to expand and opening caudal to the zygomatic arch where contract while remaining intact. the external ear attaches o In life, it is covered by the ear drum  Caudal and Dorsal Walls (tympanic membrane) which separates o Occipital bone the external and middle ear o Parietal bone o Interparietal bone  Mastoid process - located caudal to the o Frontal bones external acoustic meatus  Lateral and Ventral Walls o It is an attachment site for muscles o Temporal bones o Sphenoid bone  External occipital protuberance - the  Rostrally caudal process of the occipital bone o Ethmoid bone (unpaired) o Protuberance – protruding/gaulbo  Temporal bone - contains the middle and inner ears  Sphenoid bone - supports the brain and pituitary gland  Ethmoid bone - presents numerous openings for passage of the olfactory nerves associated with the sense of smell  Facial portion of the skull can be divided into 3 regions: o Orbit o Nasal o Oral LATERAL VIEW OF THE SKULL  Orbit - means circle o Surrounded by portions of the frontal, lacrimal and zygomatic bones  These three participate in the DORSAL VIEW OF THE SKULL formation of the zygomatic arch that borders the ventral and  Nuchal crest - the transverse ridge at the caudal parts of the orbit. transition from the dorsal to the caudal (nuchal) surfaces of the skull  Zygomatic arch - the bony arch forming the o (para siyang line na nagseseparate sa lateral wall of the orbit. dorsal at caudal surfaces) o It consists of the zygomatic bone and the zygomatic processes of the temporal  Temporal fossa - the depression formed by bone the temporal and parietal bones o Depression - luhob   Nasal aperture - the rostral bony opening into the nasal cavity SAGITTAL SECTION OF THE SKULL  Median sagittal crest - extends rostrally from  Cribriform plate - the rostral part of the wall the external occipital protuberance on the of the cranial cavity midline (absent in ruminants) o Many holes in this part of the ethmoid bone allow the passage of the olfactory nerve  Nasal cavity - the hollow space behind the nose, surrounded by the facial bones o It is divided in half longitudinally by the nasal septum and is filled by the ventral nasal conchae and ethmoturbinate bones  Ventral nasal concha - a scroll bone filling the rostral part of the nasal cavity VENTRAL VIEW OF THE SKULL  Dorsal nasal concha - the largest nasal  Foramen magnum - the large opening into turbinate of the ethmoid bone the cranial cavity for continuity of the spinal cord and brain  Ethmoid bone - the bone in the caudal nasal cavity  Tympanic bulla - the smooth bulbous o It has many bony scrolls called enlargement on the ventral side of the ethmoturbinates and its cribriform temporal bone housing the middle ear plates forms the rostral wall of the cranial o (if the temporal bone houses the middle cavity and inner ear, tympanic bulla houses the middle ear specifically)  Right and left nasal passages are separated longitudinally by the vomer bone and a  Mandibular fossa - the area on the cartilaginous and bony septum zygomatic arch for articulation with the o Septum – separates the nasal area from articular process (condyle) of the mandible left to right (idalom dampi sang ilong)  Optic canal - the passageway for the optic  Scroll-like conchae (turbinate bones) arise nerve from the eyeball to the brain from the lateral walls of the nasal cavity and o It is rostral to many other foramina that project into the nasal passages allow passage of other cranial nerves o (arises laterally not caudally or halin sa likod)  Choanae or caudal nares - the two bony openings, at the caudal end of the hard  Conchae palate, leading from the nasal cavity into the o Covered with highly vascular mucous pharynx membrane that helps warm and humidify the inspired air  Hard palate - the horizontal parts of the o Conchae on the caudal parts of the nasal incisive, palatine and maxillary bones, cavity feature the olfactory epithelium, separating the nasal and oral cavities which contains the nerve cells specialized to detect odors o (causes nose bleeds when hit hard enough)  Frontal sinus - the cavity (paranasal sinus) within the frontal bone  o Basihyoid - the unpaired bone o Stylohyoid - articulates with the base of the skull at the petrus temporal. A paired bone o Epihyoid - paired bone o Keratohyoid - paired bone o Thyrohyoid - articulates with the thyroid cartilage of the larynx. A paired bone MANDIBLE  Largest and only mobile bone of the mammalian skull o It holds the lower teeth and consists of a right and left half united at the mandibular symphysis  Body - the horizontal part bearing the lower incisor, canine, premolar and molar teeth  Mental foramen - the rostral opening of the mandibular canal  Ramus - the vertical part of the mandible bearing teeth  Articular (condylar) process - the smooth process which articulates with the mandibular fossa of the temporal bone to form the temporomandibular joint  Mandibular foramen - the opening on the THE VERTEBRAE medial side of the ramus leading into the mandibular canal  Vertebral column - spine or backbone o Protects the spinal cord, supports the head and serves as attachment for the muscles affecting body movements o It extends from the skull through the tail and consists of irregular bones vertebrae o The vertebrae are firmly joined by slightly moveable joints o The irregularly-shaped bones making up the spinal column o They are grouped by location into cervical (neck), thoracic (cranial back), lumbar (loin), sacral (croup) and caudal (tail) vertebrae o Each group is represented by its first  Hyoid apparatus - a bony framework that letter followed by the number gives support to the pharynx (throat) and representing how many are in each provides attachment to some pharyngeal, section laryngeal, and lingual muscles o Canine vertebral formula: C7 T13 L7 o It lies between the right and left portions S3 Can of the mandible and is attached to the o The number of each type of vertebrae is styloid process of each temporal bone constant except the caudal ones  o Twenty can be used as a rough estimate  The spine and the two of the caudal vertebrae with some dogs transverse processes provide having more and some less (usually sites for muscle attachment denoted by n)  The 4 articular processes (2 o Common features of a typical vertebra cranial; 2 caudal) form synovial are the body, vertebral arch, vertebral joints with adjacent vertebrae foramen and processes  Intervertebral foramen - the opening between vertebrae formed by caudal and cranial notches of adjacent vertebrae o These openings allow passage of the spinal nerves  Intervertebral discs - the fibrocartilages connecting the bodies of adjacent vertebrae  Spinous process or spine - the dorsal projection of the vertebral arch  Transverse process - the lateral extension of the vertebral arch o They divide the muscles of the back into dorsal (epaxial) and ventral (hypaxial) groups  Vertebral foramen - the space formed by  Articular process - the four articular the vertebral arch and the body process, two cranial and two caudal (8 and o The vertebral foramina of all the 8"), articulate respectively with the caudal and vertebrae form the vertebral canal, cranial articular processes of adjacent housing the spinal cord vertebrae o Vertebral canal - formed in the live o These form synovial joints animal by all vertebral foramina  Vertebral arch - the dorsal part of a vertebra that arises from the body o It consists of two upright pedicles forming the walls of the vertebral foramen o From the pedicles, two lamina project to the midline and form the roof of the vertebral foramen  Body - the thick, spool-shaped ventral portion of the vertebra o It is convex cranially and concave caudally to articulate with adjacent vertebrae CERVICAL VERTEBRAE o (concave – curve inwards, convex –  The seven vertebrae of the neck in all curve outwards) mammals, characterized by a transverse o The 7 processes of the vertebral foramen (except C7) arch o The 1st (atlas) and the 2nd (axis) cervical vertebrae are atypical  o Atypical – different morphology or not the same from the rest  Atlas - the spinous process is absent o Articulates with the occipital condyles of the skull cranially and with the axis caudally  Axis - spinous process forms a longitudinal sail on its dorsum o The body of the axis features a cranial projection called the dens (for its resemblance to a tooth), which articulates with the atlas in a pivot point.  Transverse foramen - the hole through the transverse process of C1-C6, together forming the transverse canal o This differentiates the cervical vertebrae from C7 and the remaining vertebrae THORACIC VERTEBRAE  Vertebrae of the thorax  Transverse process - of the cervical  Characterized by well-developed spinous vertebrae are divided into ventral and dorsal processes and articular facets for the ribs tubercles  Anticlinal vertebrae - the thoracic vertebra  Sixth cervical vertebra's transverse with the most vertically oriented spin, usually process - large ventral projections which on the eleventh (T11) in the dog a radiograph are used as landmarks and o All spines cranial to the vertebrae are often called the "sleds" inclined caudally, all spines caudal to it incline cranially  Seventh cervical vertebra - has a higher o This is often used as a landmark in spinous process, an articular facet on the reading radiographs of the thorax or caudal end of its body for the head of the first back rib, and no transverse foramen  Costal facets/fovea - the two plane surfaces  Atlanto-occipital joint - the "yes" joint that articulate with a rib's head o Formed between the atlas and the o Located on the caudal and cranial end of occipital bone of the cranium the vertebral bodies of most of the thoracic vertebrae  Atlanto-axial joint - the "no" joint o Formed between the atlas and the axis  Transverse costal facet - the plane surface o Dens - the peg-like cranial process on the transverse process that articulates forming a pivot articulation with the atlas, with the tubercle of the same numbered rib allowing pivotal motion  Ventral arch - the portion of the atlas replacing the body of other vertebrae  Wings - the large lateral masses that are modified transverse processes LUMBAR VERTEBRAE  The vertebrae of the lumbar (lower back, loin) region   Characterized by their large size and long o True ribs (sternal ribs) - articulate by plate-like transverse process their costal cartilage with the sternum  They can be distinguished from the last o False ribs (asternal ribs) - their costal thoracic vertebrae by their lack of costal cartilages unite to form the costal arch, facets indirectly joining them to the sternum o no costal facets = no attachment with ribs o Floating ribs - found in the dog and man, end in costal cartilages that do not join to the sternum or other costal cartilage o Head of the rib - articulates with the caudal and cranial costal facets of adjacent thoracic vertebrae and the intervening intervertebral disc o Tubercle of the rib - articulates with the articular facet on the transverse process of the same numbered vertebra o Intercostal space - the space between two adjacent ribs o Costal cartilage - the bars of hyaline cartilage either connecting the bony rib to the sternum or to the costal arch or ending freely o Costal arch - the curved structure formed by SACRUM the costal cartilages of the false ribs  The bone formed by the fusion of the sacral  Sternum or breastbone - the unpaired vertebrae bones (sternebrae) forming the floor of the o It articulates with the hip bones thorax forming the sacroiliac joint o Manubrium - the expanded first o The portion of the vertebral canal sternebrae through the sacrum is called sacral o Xiphoid process - the last sternebrae canal which is a thin, horizontal bone capped by the xiphoid cartilage  Dorsal and ventral sacral foramina - the o Thoracic inlet or cranial thoracic openings on the dorsal and ventral surfaces opening - formed by the last cervical of the bone for passage of spinal nerves vertebra, first pair of ribs and the sternum  Wings - the lateral parts of the sacrum o Thoracic outlet or caudal thoracic articulating with the hip bones to form the opening - sealed by the diaphragm sacroiliac joint Thorax  The bony cavity formed by the sternum, the ribs, the costal cartilages and the bodies of the thoracic vertebrae o The thorax encloses and protects the thoracic organs  Ribs - the long, curved bones forming the lateral wall of the thorax  APPENDICULAR SKELETON ○ Supraspinous fossa - the area cranial to the spine providing made up of the bones of the limbs attachment for the infraspinatus muscle ○ Infraspinous fossa - the area caudal to the spine providing attachment for the infraspinatus muscle ○ Subscapular fossa - most of the medial (costal) surface of the scapula providing attachment for the THORACIC LIMB subscapular muscle ○ The dorsal part of the costal surface is the serrated surface for the attachment of the serratus ventralis mmuscle ○ Glenoid cavity - the shallow cavity articulating with the head of the humerus to form the shoulder joint ○ Scapular cartilage - the cartilaginous structure on the dorsal border of the scapula ○ Supraglenoid tubercle - the process near the cranial aspect of the glenoid cavity, providing attachment for the biceps brachii muscle Clavicle (collar bone) - the bone articulating ○ Coracoid process - the small with the shoulder and the sternum in man to process on the medial side of the maintain the shoulder in a lateral position supraglenoid tubercle for the ○ The domestic animals need their attachment of the coracobrachialis thoracic limb under their bodies, so muscle the clavicle is absent or rudimentary ○ Suprahamate process - the caudal projection of the acromion found only in the cat SCAPULA ○ The distal end of the spine can be called the acromion or hamate process HUMERUS Scapula (shoulder blade) - the flat, triangular bone of the shoulder ○ The two scapulae make up the thoracic girdle ○ Spine of the scapula - the long projection dividing the scapula's lateral surface and ending as the acromion ○ Acromion - the expanded distal end of the spine of the scapula  Humerus (arm or brachial bone) - the largest bone of the thoracic limb ○ It articulates proximally with the scapula, forming the shoulder joint; ULNA AND RADIUS and distally with the radius and ulna, forming the elbow joint Head - the rounded process articulating with the scapula's glenoid cavity to form the shoulder joint Intertubercular (bicipital) groove – the sulcus between the greater and lesser tubercles through which the tendon of the biceps brachii muscle runs Greater (lateral, major) tubercle - the large process craniolateral to the head to which many muscles attach ○ The point of the shoulder is a surface feature formed by the greater tubercle Lesser (medial, minor) tubercle - the process RADIUS on the medial side of the head Body (shaft, diaphysis) - the cylindrical part Radius - the main weight-bearing bone of the connecting the two ends (epiphyses) of the forearm, articulating with the humerus and bone ulna forming the elbow joint and with the Deltoid tuberosity - the large tuberosity on carpal bones and ulna forming the the lateral side of the humerus antebrachiocarpal joint Humeral condyle - the entire distal extremity ○ Three distal grooves on its cranial of the humerus, including the two articular surface accommodate tendons areas (humeral capitulum and humeral Head - the proximal part of the radius which trochlea), and two fossae (three fossae in the articulates (fovea capitis) with the humerus cat) and the lateral and medial epicondyles (capitulum) and ulna Lateral epicondyle - the lateral side of the Carpalarticular surface - the articular humeral condyle, giving rise to the extensors surface on the distal end of the radius of the forearm Functionally, it is known as the (trochlea) which articulates with the carpal extensor epicondyle bones Medial epicondyle - the medial-most point of Styloid process of radius - distal end of the the humeral condyle, functionally known as radius the flexor epicondyle because it provides ULNA attachment for the flexor muscles of the Ulna - the long, thin bone serving mainly for forearm muscle attachment and formation of the Olecranon fossa - the caudal excavation elbow joint receiving the proximal end of the ulna on ○ Proximally it articulates with the extension of the elbow humerus and radius, distally with the Radial fossa - the excavation opposite the radius and the carpal bones olecranon fossa receiving the proximal end of Olecranon - the proximal part of the ulna the radius on flexion of the elbow providing a lever arm for the extensor ○ The cat has a small coronoid fossa muscles of the elbow. It forms the points of medial to the radial fossa for the the elbow medial coronoid process of the ulna Trochlear notch - the depression for on flexion of the elbow articulation with the humerus and ending in the anconeal process Anconeal process - the proximal end of the trochlear notch which fits in the olecranon fossa of the humerus when the elbow is extended Medial coronoid process - the large distal end of the trochanter notch  Styloid process of the ulna - the pointed, ○ Ulnar - laterally located bone in the distal end of the ulna proximal row Interosseous space - the space between the ○ Accessory - projects behind ulna and radius, readily seen in the carnivores (palmar) carpus, articulating with the and pig ulnar carpal The only carpal bone to which muscles attach CARPUS (flexor carpi ulnaris and extensor carpi ulnaris) Distal Row ○ Consists of the 1st, 2nd, 3rd and 4th carpal bones in the generalized pattern METACARPUS Manus ○ The distal part of the thoracic limb, consisting of the carpus, metacarpus. phalanges and their associated sesamoid bones ○ It is also called the forepaw in the carnivores Metacarpus Carpus (wrist) ○ The region of the manus located ○ The carpal bones, also the between the carpus and digits compound joint formed by these ○ Metacarpal bones - the generalized bones, or the region between the metacarpus has five bones forearm and metacarpus numbered I-V from medial to later ○ Each bone is composed of a: Carpal Bones base articulating with the ○ The two rows of bones forming the carpus carpus head articulating with the ○ The number of carpal bones varies proximal phalanx of digit between species due to fusion shaft connecting the two between bones or absence of one or extremities more bones At least one sesamoid ○ The proximal row consists of the bone is associated with radial carpal intermedial carpal each metacarpal bone ulnar carpal, and accessory carpal Carnivore Metacarpal Bones ○ The distal row, from medial to lateral, ○ The generalized pattern of five consists of carpal ones 1-4 metacarpal bones ○ Metacarpal I is much reduced and Proximal Row bears no weight ○ Radial - the largest carpal bone, ○ It is part of the dew claw medially located ○ Intermediate - between the radial and ulnar carpal bones  DIGITS ○ Ungual process - the tapered, cone-shaped process covered by the horny claw ○ Horny claw - the fingernail-like structure covering the ungual process Carnivore Digits - four main weight bearing digits (II-IV) ○ Palmar sesamoid bones the nine small bones at the metacarpophalangeal joint Two for each main digits and one for the 1st digit The bones corresponding to the fingers and toes of man ○ There are five digits in the generalized pattern, numbered from medial to lateral (I-V) ○ Species differences are due to reduction in the number of digits ○ The digits generally consist of three phalanges and a number of sesamoid bones Carnivore Digits - four main weight bearing digits (II-IV) ○ Dew claw - the Ist digit and the 1st metacarpal bone Reduced in size having only two phalanges, the proximal and distal, and one proximal sesamoid bone Some dog breeds have double dewclaws ○ Proximal phalanx - the first phalanx divided into the base, body and head ○ Middle phalanx - the second phalanx