Intro to Anatomy PDF

Introduction to Anatomy Sushama Rich, MD  Introduction to Anatomy Anatomic terminology, planes, overview of systems Objectives 1. Describe the normal anatomic position of the body and list the anatomic terms appropriate to this position. 2. List the planes of the body and...

Introduction to Anatomy Sushama Rich, MD  Introduction to Anatomy Anatomic terminology, planes, overview of systems Objectives 1. Describe the normal anatomic position of the body and list the anatomic terms appropriate to this position. 2. List the planes of the body and relate the movements that occur along these planes. 3.List terms of movement. 4. Recognize the differences between types of muscles and their function. 5. Distinguish between fascia, tendons and ligaments from each other and give an example of each. Objectives 6. List the bones of the body and designate whether they belong to axial or appendicular portions of the 7. Understand the classes of joints, based on their structure and function 8. Explain how actions produced by skeletal muscles are influenced by attachments and reflect on their actions on joints. 9. Distinguish between the different types of nervous systems and their functions 10. List the different systems of the body and explain their functions Approaches to studying Anatomy Anatomy: Is the study of the structure of the human body Regional Anatomy each region of the body is studied separately and all aspects of that region are studied at the same time. Ex: Head, neck, gluteal region Systemic anatomy each system of the body is studied and followed throughout the entire body Ex: circulatory system Clinical Anatomy integrates both regional and systemic  objective Describe the normal anatomic position of the body and list the anatomic terms appropriate to this position. Normal Anatomical Position Anatomic terminology Supine : lying face up Prone: lying face down  Anatomic terminology Anterior (Ventral)............at the front Posterior (Dorsal)............at the back. Cranial (Cephalic)...............toward the head. Caudal..............toward the tail. Medial..............nearer the midline of the body or a structure. Lateral..............Farther away from the midline of the body or a structure.  objective List the planes of the body and relate the movements that occur along these planes. Anatomical planes Median plane Sagittal plane Coronal plane Transverse plane objective List terms of movements Anatomic terms for movement General terms : Flexion and extension Flexion and extension describe movements that affect the angle between two parts of the body. Anatomic terms for movement Flexion A bending movement that decreases the angle between two parts. Ex: When sitting down, the knees are flexed Anatomic terms for movement Extension: Is the opposite of flexion, Movement that increases the angle between body parts. Ex: When standing up, the knees are extended.  Anatomic Terms For Movement Abduction and adduction Refer to motions that move a structure away from or towards the center of the body. Anatomic terms for movement Abduction: Refers to a motion that pulls a structure or part away from the midline of the body. In the case of fingers and toes, spreading the digits apart, away from the center of the hand or foot. Raising the arms laterally, such as when tightrope-walking, is an example of abduction at the shoulder. Anatomic terms for movement Adduction: Refers to a motion that pulls a structure or part toward the midline of the body. EX: Dropping the arms to the sides, or bringing the knees together. Anatomic terms for movement Rotation of body parts is referred to as internal or external, referring to rotation towards or away from the center of the body. Anatomic terms for movement Internal rotation (or medialrotation)the turning of a limb about its axis of rotation toward the midline of the body. Anatomic Terms For Movement External rotation (or lateral rotation) refers to rotation away from the center of the body. Anatomic Terms For Movement Circumduction: refers to a conical movement of a body part, such as a ball- and-socket joint ( such as the hip and shoulder) or the eye. It is a combination of flexion, extension, adduction and abduction. Example of circumduction occurs when performing a serve in tennis.  Anatomic terms for movement Elevation and depression refer to movement above and below the horizontal. Elevation refers to movement in a superior direction. Ex: Shrugging your shoulder Depression refers to movement in an inferior direction, the opposite of elevation. Ex: opposite of shrugging Anatomic Terms For Movement Special movements of the hands and feet Flexion and extension of the foot Dorsiflexion: Where the toes are brought closer to the shin. It decreases the angle between the dorsum of the foot and the leg. Ex: includes the position of the foot when walking on the heels. Flexion and extension of the foot Plantar flexion is the movement which decreases the angle between the sole of the foot and the back of the leg. Ex: when depressing an car pedal or standing on the tiptoes. Flexion and extension of the hand Palmarflexion: Refers to decreasing the angle between the palm and the forearm. Dorsiflexion: Refers to extension at the wrist joint Pronation and supination Refers to rotation of the forearm or foot so that in the anatomical position the palm or sole is facing anteriorly (supination) or posteriorly (pronation) Pronation and supination Pronation: When the forearm or palm is turned inwards. Supination: When the forearm or palm are rotated outwards Inversion and Eversion of the foot Eversion: Is the movement of the sole of the foot away from the median plane. Inversion is the movement of the sole towards the median plane Special Movements at the Jaw Elevation Depression Elevation Depression Movements ACROSS THE VERTEBRAL COLUMN  Movements at the cervical region Flexion Extension Lateral bending Rotation  Rotation Lateral bending Movements AT THE SCAPULA Movements at the scapula Elevation Depression Protraction Retraction Upward rotation Downward rotation Upward and downward rotation Movements AT THE SHOULDER JOINT Movements at the shoulder Flexion Extension Horizontal abduction Horizontal adduction Internal rotation External rotation Circumduction FLEXION EXTENSION HORIZONTAL ABDUCTION Horizontal adduction Internal rotation, and external rotation Movements AT THE ELBOW JOINT Movements at the elbow Flexion Extension Movements AT THE RADIO ULNAR JOINT Movements AT THE WRIST JOINT Movements at the wrist joint Flexion Extension Radial deviation Ulnar deviation Circumduction Movements AT THE THUMB Movements at the fingers Movements at the fingers Flexion Extension Abduction Adduction Movements AT THE HIP JOINT Movements at the hip joint Flexion Extension Abduction Adduction Internal rotation External rotation Circumduction  Movements AT THE KNEE JOINT Movements at the knee joint Flexion Extension  Movements AT THE ANKLE JOINT  Movements at the ankle joint Dorsiflexion Plantar flexion Movements AT THE SUBTALAR JOINT Movement at the subtalar joints Inversion Eversion  Movements AT THE TEMOROMANDIBULAR JOINT Movements at the TMJ Protrusion Retrusion Objectives 1. Describe the normal anatomic position of the body and list the anatomic terms appropriate to this position. 2. List the planes of the body and relate the movements that occur along these planes. 3.List terms of movement. 4. Distinguish between fascia, tendons and ligaments from each other and give an example of each 5. Recognize the differences between types of muscles and their function Objectives 6. List the bones of the body and appendicular portions of the skeleton. 7. Understand the classes of joints, based on their structure and function. 8. Explain how actions produced by skeletal muscles are influenced by attachments and reflect on their actions on joints. 9. Distinguish between the different types of nervous systems and their functions 10. List the different systems of the body and explain their functions  objective Distinguish between fascia, tendons and ligaments from each other and give an example of each Skin and Fascia The skin is the largest organ of the body. It consists of the epidermis and the dermis. The epidermis is the outer cellular layer of stratified squamous epithelium, which is avascular and varies in thickness. The dermis is a dense bed of vascular connective tissue  Fascia, fascial compartments, bursae Fascia: constitute the wrapping, packing, and insulating materials of the deep structures of the body. Superficial and deep. Superficial: The deep fascia is a dense, organized connective tissue layer, devoid of fat. Fascia, fascial compartments, bursae Types of deep fascia Investing fascia: Extensions of deep fascia that invest deeper structures, such as individual muscles and neurovascular bundle. Intermuscular septa, that extend centrally from the surrounding fascial sleeve to attach to bones. Retinaculum: The deep fascia becomes markedly thickened Fascia, fascial compartments, bursae Bursa: are closed sacs or envelopes of serous membrane (a delicate connec-tive tissue membrane capable of secreting uid to lubricate  Tendon Tendon : is a tough band of fibrous connective tissue that usually connects muscle to bone and is capable of withstanding tension. Tendons consist of dense regular connective tissue fascicles encased in dense irregular connective tissue sheaths. Ligaments Ligament is the fibrous connective tissue that connects bones to other bones and is also known as articular ligament. Ligament can also refer to: Peritoneal ligament: a fold of peritoneum or other membranes. Fetal remnant ligament: the remnants of a fetal tubular structure. Periodontal ligament. BODY SYSTEMS MUSCULAR SYSTEM  objective Recognize the differences between types of muscles and their function.  Muscular system Muscles Types of Muscles Skeletal cardiac Smooth Functions Movement Maintenance of body posture Production of heat  Muscles Muscles: Drive all the movements in the human body, both voluntary and involuntary. Specific anatomic terminology is used to describe movement. The terminology describes movement according to its direction. Anatomists use a unified set of terms to describe most of the movements.  Muscles Skeletal muscle contraction Tonic contraction Phasic contraction Isotonic>muscle length changes Concentric> contraction of muscle occurs (prime mover) Eccentric> muscle lengthens Isometric> muscle length remains same  Functions of muscles Prime mover (agonist) is the main muscle responsible for producing a specific movement of the body It contracts concentrically Fixator steadies the proximal parts of a limb through isometric contraction while movements are occurring in distal parts Synergist complements the action of a prime mover Antagonist is a muscle that opposes the action of another muscle Biceps curl Agonist or Prime mover is Biceps Antagonist: Triceps the antagonist typically relaxes so as not to impede the arm. Fixator: In the bicep curl this would be the rotator cuff muscles, the 'guardians of the shoulder joint. Synergist: synergist muscles are the brachioradialis and brachialis which assist the biceps to create the movement and stabilise the elbow j ORGAN SYSTEMS Skeletal system  objective List the bones of the body and appendicular portions of the skeleton.  Skeletal system 1. Structure a. Bones b. Joints c. Ligaments, tendons, cartilage 2. Functions a. Support b. Movement (with joints and muscles) c. Storage of minerals d. Blood cell formation  TYPES OF BONES Long bones------femur, humerus Short bones-----wrist bones, ankle bones Flat bones-------skull bones, sternum Irregular bones----spine , pelvis, sphenoid, ethmoid Sesamoid bones----found inside tendons, patella  Long bone 1. Diaphysis: shaft; long axis 2. Epiphysis: bone ends a. Exterior is compact bone b. Interior is spongy bone c. Articular cartilage covers joint surface absorbs stress. d. Epiphyseal plate: growth plate is a hyaline cartilage plate in the metaphysis at each end of a long bone. remnant e. Ephyseal line: of epiphyseal plate in adults  Objective Understand the classes of joints, based on their structure and function.  Joint Joint is the location at which bones connect. They are constructed to allow movement (except for skull bones) and provid. mechanical support, and are classified structurally and functionally.  Structural classification of joints Fibrous joint - joined by dense regular connective tissue that is rich in collagen fibers. Cartilaginous joint - joined by cartilage. Synovial joint - not directly joined - the bones have a synovial cavity and are united by the dense irregular connective tissue that forms the articular capsule that is normally associated with accessory ligaments. Fibrous joints They are connected by dense connective tissue, consisting mainly of collagen. In these joints the bones are firmly interlocked by irregular hacksaw-like edges. These are fixed joints where bones are united by a layer of white fibrous tissue of varying thickness  Types of fibrous joints Sutures are found between bones of the skull. In fetal skulls the sutures are wide to allow slight movement during birth. They later become rigid (synarthrodial).  Types of fibrous joints Syndesmoses are found between long bones of the body, such as the radius and ulna in forearm and the distal tibio-fibular joint in leg. Unlike other fibrous joints, syndesmoses are moveable (amphiarthrodial), albeit not to such degree as synovial joints. Types of fibrous joints Gomphosis is a joint between the root of a tooth and the sockets in the maxilla or mandible. Cartilaginous joint Primary cartilaginous joint: Examples in humans are the "growth plates" between ossification centers in long bones. These joints here allow for only a little movement, such as in the spine or ribs.  Cartilaginous joint Secondary cartilaginous joints: Known as "symphyses". Fibrocartilaginous and hyaline joints, usually occurring in the midline. Examples in human anatomy would be the manubriosternal joint (between the manubrium and the sternum), intervertebral discs, and the pubic symphysis. Synovial joints Joint cavity Capsule Outer fibrous capsule Made of dense connective tissue Inner synovial membrane Synovial fluid Bursae :Pockets of synovial membrane and fluid that extend from the joint; They are found in areas of friction such as shoulder or knee they provide extra cushion  Synovial joints Six major types of synovial joints: 1. Plane joints 2. Hinge joints 3. Saddle joints 4. Condyloid 5. Ball and socket 6. Pivot joint  Plane joints Plane joints permit gliding or sliding movements Opposed surfaces of the bones are flat Small joints Ex; AC joint Hinge joint Hinge joints permit flexion and extension Movements that occur in one plane (sagittal) Uniaxial Joint capsule of these joints is thin Strong, laterally placed collateral ligaments. Ex; elbow joint, knee joint  Saddle joint Shaped like a saddle. They are reciprocally concave and convex. Saddle joints permit abduction, adduction, flexion , extension and circumduction. Biaxial: two axes at right angles to each other. Allow movement in two planes, sagittal and frontal. Ex: CMC of the thumb  Condyloid joints Permit flexion and extension as well as abduction and adduction; Circumduction- restricted. Also biaxial. Movement in one plane (sagittal) is usually greater (freer) than in the other. Ex: metacarpophalangeal joints.  Ball and socket joint Movement in multiple axes and planes. Flexion, extension, abduction, adduction, medial and lateral rotation, and circumduction. Multi-axial joints. Ex: hip, shoulder  Pivot joints Permit rotation around a central axis. They are uniaxial. A rounded process of bone rotates within a sleeve or ring. Ex: atlantoaxial joint.  Bone Markings Facet: smooth flat area, usually covered with cartilage. Foramen: passage through a bone. Spine: thorn-like process Fossa: hollow or depressed area. Bone Markings Malleolus: rounded process. Trochlea: spool-like articular process or process that acts as a pulley. Notch: indentation at the edge of a bone. Protuberance: projection of bone.  Bone Markings Head Trochanter: large blunt elevation. Line: linear elevation Bone Markings Capitulum: small, round, articular head. Condyle: rounded, knuckle-like articular area, often occurring in pairs. Epicondyle: eminence superior to a condyle. Groove: elongated depression Vasculature of Bone Nutrient arteries enter though nutrient foramina. Nutrient arteries divide into longitudinal branches. Periosteal arteries supply compact bone. Veins accompany arteries. Innervation of bone Periosteum is richly supplied by sensory nerves called periosteal nerves. Vasomotor nerves supply blood vessels regulating blood flow. Circulatory system Transports fluids It consists of the cardiovascular and lymphatic systems. The heart and blood vessels make up the cardiovascular system. This system pumps blood through the body’s vast system of blood vessels. Cardiovascular system Vascular circuits Pulmonary and systemic Cardiovascular system Blood Vessels: Three types: arteries, veins, and capillaries Blood distributed to the body by a branching system of thick-walled arteries. The final distributing vessels, arterioles, deliver oxygen-rich blood to capillaries Cardiovascular system Blood from the capillary bed passes into thin- walled venules– veins– largest veins are SVC and IVC. Most blood vessels have three coats or tunics. Tunica intima, media and externa Blood vessels Tunica intima contains a single layer of epithelial cells called endothelium. Tunica media consisting primarily of smooth muscle. Tunica adventitia, an outer connective tissue layer or sheath. Arteries Large elastic arteries have many elastic layers. They are the conducting arteries. Ex: aorta, brachicephalic trunk, subclavian and the pulmonary trunk. Arteries Medium muscular arteries are distributing arteries. They have walls that consist chiefly of circularly disposed smooth muscle fibers. Their ability to decrease their diameter (vaso constrict) regulates the flow of blood. Ex; Brachial and femoral. Arteries Small arteries and arterioles have relatively narrow lumina and thick muscular walls. The degree of filling of the capillary beds and level of arterial pressure is regulated mainly by the degree of tonus (firmness) in their smooth muscle of the arte- riolar walls. When tonus is above normal results in hypertension. Arteries Anastomoses (communications) between multiple branches of an artery provide collateral circulation. End arteries. Veins Venules– medium veins--- large veins Veins have valves. Veins are more abundant than arteries. There thin walls allow veins to have a large capacity for expansion. Only 20% of the blood occupies arteries, whereas 80% is in the veins. AVA Arteriovenous anastomosis. In some regions, such as in the fingers, there are direct connections between the small arterioles and venules. AV shunts are numerous in the skin, where they have an important role in conserving body heat. Clinical correlates Arteriosclerosis Hardening of arteries. Most common cause is atherosclerosis. Results in ischemia. The atheroma eventually bursts and a blood clot (thrombus) forms. Can occlude the artery May cause infarction. Lymphoid system Constitutes a sort of “over- flow” system that provides for the drainage of surplus tissue fluid and leaked plasma proteins to the bloodstream, as well as for the removal of debris from cellular decomposition and infection. It constitutes a major part of the body’s defense system. Lymphoid system Components are lymphatic capillaries, lymphatic plexuses; lymphatic vessels; lymph; lymph nodes; lymphocytes; and the lymphoid organs. Provides a (relatively) predictable route for the spread of certain types of cancerous cells throughout the body. Lymphoid system Superficial lymphatic vessels, converge toward and follow the venous drainage. These vessels eventually drain into deep lymphatic vessels that accompany the arteries and also receive the drainage of internal organs. Lymphoid system Large lymphatic vessels enter large collecting vessels, called lymphatic trunks. These in turn unite to form either the right lymphatic duct or the thoracic duct. Lymphoid system The right lymphatic duct drains lymph from the body’s right upper quadrant (right side of head, neck, and tho-rax plus the right upper limb). At the root of the neck, it enters the junction of the right internal jugular and right subclavian veins, the right venous angle. Lymphoid system The lymphatic trunks draining the lower half of the body merge in the abdomen, sometimes forming a dilated collecting sac, the cisterna chyli. The thoracic duct starts from here, enters the junction of the left internal jugular and left subclavian veins, the left venous angle. ORGAN SYSTEMS Nervous system Nervous system Enables the body to react to continuous changes in its internal and external environments. It also controls various activities of the body, such as circulation and respiration. For descriptive purposes, the nervous system is divided: Structurally into the central nervous system (CNS), the peripheral nervous system (PNS), Functionally into the somatic nervous system (SNS) and the autonomic nervous system (ANS).  Neuron Neurons are the core components of the nervous system. Is an electrically excitable cell Processes and transmits information through electrical and chemical signals. Signals between neurons occur via synapses. Specialized types of neurons include: sensory neurons and motor neurons. Neuron Possesses cell body Dendrites Axon Dendrites are thin structures that arise from the cell body, often extending for hundreds of micrometres and branching multiple times, giving rise to a complex "dendritic tree".  Neuron An axon is a special cellular extension that arises from the cell body at a site called the axon hillock and travels for a distance, as far as 1 meter in humans or even more in other species. Myelin, layers of lipid, and protein substances form a myelin sheath around some axons, this greatly increasing the velocity of impulse conduction.  NUCLEUS dendrites axon Axon ending Myelin sheath Cell body  Neuron Two types of neurons Multipolar motor neurons. Have two or more dendrites and a single axon. Most common type of neuron. All of the motor neurons that control skeletal muscle and those comprising the ANS are multipolar neurons.  Neurons Pseudounipolar sensory neurons have a short, single process extending from the cell body. This common process separates into a peripheral process, conducting impulses from the receptor organ toward the cell body. And a central process that continues from the cell body into the CNS. The cell bodies of these neurons are located outside the CNS in sensory ganglia and are thus part of the PNS. Neuroglia Also called glial cells or glia. Five times as abundant as neurons. Non-excitable cells. They are supporting insulating , and nourishing the neurons. In the CNS, neuroglia include oligodendroglia, astrocytes, ependymal cells, and microglia (small glial cells). Synapses Neurons communicate with each other at points of contact between neurons. The communication occurs by means of neurotransmitters. Chemical agents released or secreted by one neuron. This may excite or inhibit another neuron. Central nervous system  Central nervous system Composed of brain and spinal cord. The principal roles of the CNS are to integrate and coordinate incoming and outgoing neural signals and to carry out higher mental functions, such as thinking and learning.  CNS A nucleus :is a collection of nerve cell bodies in the CNS. Tract: A bundle of nerve fibers (axons) within the CNS connecting neighboring or distant nuclei of the cerebral cortex CNS The brain and spinal cord are composed of gray matter and white matter. The nerve cell bodies lie within and constitute the gray matter The interconnecting fiber tract systems form the white matter. CNS In the brain the gray mater is on the periphery and the white matter on the inside. In the spinal cord the opposite is true.  CNS In transverse sections of the spinal cord, the gray matter appears roughly as an H-shaped area embedded in a matrix of white matter. The struts of the H are horns; hence there are right and left posterior (dorsal) and anterior (ventral) gray horns. Peripheral nervous system Peripheral nervous system PNS consists of nerve fibers and cell bodies outside the CNS. They conduct impulses to or away from the CNS. The PNS is organized into nerves that connect the CNS with peripheral structures.  PNS A nerve fiber consists of an axon its neurolemma surrounding endoneurial connective tissue  PNS A nerve consists of: A bundle of nerve fibers outside the CNS. There is connective tissue coverings that surround and bind the nerve fibers. The blood vessels (vasa nervorum) that nourish the nerve fibers and their coverings  Coverings of a nerve Endoneurium: delicate connective tissue immediately surrounding the neurilemma cells and axons. Perineurium: a layer of dense connective tissue that encloses a fascicle of nerve fibers, providing an effective barrier against penetration by foreign substances. Epineurium: a thick connective tissue sheath forming the outermost covering of the nerve; it includes fatty tissue, blood vessels, and lymphatics  PNS Nerves are either cranial nerves or spinal nerves. Cranial nerves exit the cranial cavity through foramina in the cranium. CN XI arises from the superior part of the spinal cord. Spinal nerves arise in bilateral pairs from a specific segment of the spinal cord. 31 spinal cord segments and the 31 pairs of nerves. Spinal Nerves Spinal nerves initially arise from the spinal cord as rootlets. The rootlets converge to form two nerve roots. An anterior (ventral) nerve root and a A posterior (dorsal) nerve root.  Spinal nerves Dermatome The unilateral area of skin innervated by the sensory fibers of a single spinal nerve. Myotome: Unilateral muscle mass receiving innervation from the fibers conveyed by a single spinal nerve. AUTONOMIC NERVOUS SYSTEM  Overview of ANS Controls autonomic functions Two neurons, a presynaptic and a postsynaptic fiber, connect the CNS with an end organ. An end organ is a smooth muscle, gland, or modified cardiac muscle Based on the location of the cell body of the presynaptic fibers, the ANS can be subdivided into two divisions: the sympathetic and parasympathetic Sympathetic nervous system The SNS innervates visceral motor tissues both in the body wall and internal organs. The PNS does not innervate structures in the body wall but is confined to innervation of internal organs Parasympathetic nervous system Promotes intake of energy Cranio sacral outflow. Cranial nerves 3, 7, 9, 10 carry parasympathetic innervation. Sacral outflow: S2-S4 Functions of ANS Sympathetic and parasympathetic divisions usually have opposite but coordinated effects. Sympathetic system (flight-or-fight) responses Parasympathetic system —rest and digest Organ Effect of Sympathetic Stimulation Effect of Parasympathetic , Stimulation Tract, Eyes Dilates pupil (admits more light Constricts pupil (protects pupil for increased acuity at a distance) from excessively bright light)Contracts ciliary muscle, allowing lens to thicken for near vision (accommodation) Skin Causes hairs to stand on end No effect (does not reach) (“gooseflesh”or “goose bumps”) Vasoconstricts (blanching of skin, lips, and turning fingertips blue)Promotes sweating Other Slightly decreases secretions Promotes secretion Promotes gland Secretion decreases, becomes abundant, watery secretion s thicker, more viscous Heart increases the rate and strength of Decreases the rate and strength contraction; inhibits the effect of of con-traction (conserving parasympathetic system on energy); constricts coronary coronary vessels, allowing them vessels in relation to reduced Organ, Effect of Sympathetic Effect of Parasympathetic Tract, Stimulation Stimulation Digestive inhibits peristalsis, and Stimulates peristalsis and tract constricts blood vessels to secretion of digestive juices digestive tract so that blood Contracts rectum, inhibits is available to skeletal internal anal sphincter to muscle; contracts internal cause defecation anal sphincter to aid fecal continence Liver and Promotes breakdown of Promotes gallbladd glycogen to glucose (for building/conservation of er increased energy) glycogen; increases secretion of bile Urinary Vasoconstriction of renal inhibits contraction of internal tract vessels slows urine sphincter of bladder, contracts formation; internal detrusor muscle of the sphincter of bladder bladder wall causing urination contracted to maintain urinary continence Thank you Please feel free to reach out to me via email with any questions. 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