Seeley's Essentials Of Anatomy & Physiology PDF

Seeley’s ESSENTIALS OF Anatomy...

Seeley’s ESSENTIALS OF Anatomy & Physiology Tenth Edition Cinnamon Vanputte Jennifer Regan Andrew See separate Russo PowerPoint slides for all figures and tables pre-inserted into PowerPoint without notes. © 2019 McGraw-Hill Education. All rights reserved. Authorized only for instructor use in the classroom. No reproduction or further distribution permitted without the prior  2 Chapte r7 Muscular System Lecture © 2019 McGraw-Hill Outline  3 Types of Muscles Skeletal  attached to bones  striated  voluntarily controlled Cardiac  located in the heart  striated  involuntarily controlled © 2019 McGraw-Hill  4 Types of Muscles Smooth  Located in blood vessels, hollow organs  Non-striated  involuntarily controlled © 2019 McGraw-Hill Comparison of Skeletal, Cardiac, and Smooth Muscles Characteristics 5 Skeletal Cardiac Body Smooth to Attached Walls of the Mostly in location bones or, for heart walls of some facial hollow Cell shape musclesvery to Single, Branching visceral Single, and skin long, chains of cells; organs fusiform, appearance cylindrical, uninucleate, uninucleate, multi- striations; no striations nucleate cells intercalated Connective with very Epimysium, discs Endomysium Endomysi tissue obvious perimysium, attached to um components striations and the fibrous endomysium skeleton of Regulation Voluntary, the heart Involuntary; the Involuntary; of via nervous heart has nervous contractio system pacemaker; system n control nervous system controls; © 2019 McGraw-Hill control; hormone hormones, Characterist Skeletal Cardiac Smooth 6 ics Speed of Slow to fast slow Very slow Contraction Rhythmic N Yes Yes, in some contraction o © 2019 McGraw-Hill  7 © 2019 McGraw-Hill  8 The Muscular System Functions  Movement  Maintain posture  Respiration  Production of body heat  Communication  Heart beat  Contraction of organs and vessels Figure © 2019 McGraw-Hill 7.1  9 Properties of Muscles Contractility  the ability of muscle to shorten forcefully, or contract Excitability  the capacity of muscle to respond to a stimulus © 2019 McGraw-Hill  1 Properties of Muscles 0 Extensibility  ability to be stretched beyond it normal resting length and still be able to contract Elasticity  ability of the muscle to recoil to its original resting length after it has been stretched © 2019 McGraw-Hill  1 Skeletal Muscle Structure 1 1  Skeletal muscle, or striated muscle, with its associated connective tissue, constitutes approximately 40% of body weight.  Skeletal muscle is so named because they are attached to the skeletal system.  Some skeletal muscles attach to the skin or connective tissue © 2019 McGraw-Hill  1 Skeletal Muscle Structure 2 2  Skeletal muscle is also called striated muscle because transverse bands, or striations. © 2019 McGraw-Hill  1 Connective Tissue Coverings 3  Epimysium a connective tissue sheath that surround each skeletal muscle  A skeletal muscle is subdivided into groups of muscle cells, termed fascicles.  Perimysium -surround the fascicle.  Endomysium - surround each skeletal muscle cell (fiber) © 2019 McGraw-Hill  1 Muscle Fiber Structure 4 1  a single cylindrical cell, with several nuclei located at its periphery.  It range in length 1 cm to 30 cm and are generally 0.15 mm in diameter.  Skeletal muscle fibers contain several nuclei that are located at the periphery of the fiber.  The sarcolemma (cell membrane) © 2019 McGraw-Hill  1 Muscle Fiber Structure 5 2  T tubules occur at regular intervals along the muscle fiber and extend into the center of the muscle fiber.  The T tubules are associated with enlarged portions of the smooth endoplasmic reticulum called the sarcoplasmic reticulum.  The enlarged portions are called terminal cisternae.  T tubules connect the sarcolemma to © 2019 McGraw-Hill  1 Muscle Fiber Structure 6 3  Sarcoplasm it the cytoplasm of a muscle fiber which contains many bundles of protein filaments.  Myofibrils are bundles of protein filaments.  Myofibrils consist of the myofilaments, actin and myosin. © 2019 McGraw-Hill  1 7 Figure 8.1 © 2019 McGraw-Hill  1 Structure of Skeletal Muscle 8 Figure © 2019 McGraw-Hill 7.2  1 Sarcomere 9 1  the basic structural and functional unit of a skeletal muscle capable of contracting.  Z Disks - form a network of protein fibers that serve as an anchor for actin myofilaments and separate one sarcomere from the next.  A sarcomere extends from one Z disk to the next Z disk. © 2019 McGraw-Hill  2 The Sarcomere 0 2  The organization of actin and myosin myofilaments gives skeletal muscle its striated appearance and gives it the ability to contract.  The myofilaments slide past each other, causing the sarcomeres to shorten.  Each sarcomere consists of two light-staining bands separated by a © 2019 McGraw-Hill  2 1 Figure 8.2c © 2019 McGraw-Hill  2 The Sarcomere 2 3  I bands -light bands, consist only of actin myofilaments that extends toward the center of the sarcomere to the ends of the myosin myofilaments.  A bands -dark staining bands that extend the length of the myosin myofilaments.  Actin and myosin myofilaments overlap for some distance on  2 3 Figure 8.2c © 2019 McGraw-Hill  2 The Sarcomere 4 4  Actin myofilaments are made up of three components: Actin, Troponin, and Tropomyosin.  Troponin -molecules have binding sites for Ca2+  Tropomyosin - filaments block the myosin myofilament binding sites on the actin myofilaments.  Myosin myofilaments, or thick myofilaments, resemble bundles of tiny golf clubs. © 2019 McGraw-Hill  2 5 Figure 8.3a © 2019 McGraw-Hill  2 6 Figure 8.3b © 2019 McGraw-Hill  2 7 Sliding Filament Mechanism During contraction myosin heads bind actin sites Pull and slide actin molecules (and Z-discs) toward H-zone I-bands and H-zones narrow Sliding generates force and shortens sarcomeres. © 2019 McGraw-Hill  2 8 Figure 8.4 © 2019 McGraw-Hill  2 Skeletal Muscle Fiber 9 Figure © 2019 McGraw-Hill 7.3  3 Excitability of Muscle Fibers 0  Muscle cells (fibers) have a resting membrane potential, but can also perform action potentials. Resting Membrane Potential  the inside of the membrane is negatively charged and the outside of the membrane is positively charged. Action potentials  due to the membrane having gated © 2019 McGraw-Hill  3 Resting Membrane Potential 1 1 The resting membrane potential exists because of:  The concentration of K+ being higher on the inside of the cell membrane and the concentration of Na+ being higher on the outside  The presence of many negatively charged molecules, such as proteins, inside the cell that are too large to exit the cell  The presence of leak protein channels in the membrane that are more permeable to © 2019 McGraw-Hill  3 Resting Membrane Potential 2 2  Na+ tends to diffuse into the cell and K+ tends to diffuse out.  In order to maintain the resting membrane potential, the sodium- potassium pump recreates the Na+ and K+ ion gradient by pumping Na+ out of the cell and K+ into the cell. © 2019 McGraw-Hill  3 Resting Membrane Potential 3 3 Figure 7.4 © 2019 McGraw-Hill (1)  3 Action Potential 4 1  Resting membrane potential must be changed to an action potential.  Changes in the resting membrane potential occur when gated cell membrane channels open.  In a skeletal muscle fiber, a nerve impulse triggers gated Na+ channels to open and Na+ diffuses into the cell down its concentration gradient and toward the negative © 2019 McGraw-Hill  3 Action Potential 5 2  The entry of Na+ causes the inside of the cell membrane to become more positive than when the cell is at resting membrane potential.  This increase in positive charge inside the cell membrane is called DEPOLARIZATION.  If the depolarization changes the membrane potential to a value called threshold, an action potential is triggered. © 2019 McGraw-Hill  3 Action Potential 6 3  Depolarization during the action potential is when the inside of the cell membrane becomes more positively charged than the outside of the cell membrane.  Near the end of depolarization, the positive charge causes gated Na+ channels to close and gated K+ channels to open.  Opening of gated K+ channels starts © 2019 McGraw-Hill  3 Action Potential 7 4  Repolarization is due to the exit of K+ from the cell.  The outward diffusion of K+ returns the cell to its resting membrane conditions and the action potential ends.  In a muscle fiber, an action potential results in muscle contraction. © 2019 McGraw-Hill  3 Depolarization 8  change in charges inside becomes more + and outside more –  Na+ channels open Figure 7.4 © 2019 McGraw-Hill (2)  3 Repolarization 9  Na+ channels close  change back to resting potential Figure 7.4 © 2019 McGraw-Hill (3)  4 Ion Channels and Action Potentials 0 Figure © 2019 McGraw-Hill 7.4  Nerve Supply & Muscle Fiber 4 1 Stimulation1  Motor neuron - a nerve cell stimulates muscle cells.  Neuromuscular junction-a synapse where a the fiber of a nerve connects with a muscle fiber.  Synapse refers to the cell-to-cell junction between a nerve cell and either another nerve cell or an effector cell.  Motor unit -a group of muscle © 2019 McGraw-Hill  4 Nerve Supply 2 2  Presynaptic terminal is the end of a neuron cell axon fiber.  Synaptic cleft is the space between the presynaptic terminal and postsynaptic  membrane. Postsynaptic muscle membrane is the fiber membrane (sarcolemma).  Synaptic vesicle is a vesicle in  4 Nerve Supply 3 3  Neurotransmitters - are chemicals that stimulate or inhibit postsynaptic cells.  Acetylcholine - the neurotransmitter that stimulates skeletal muscles.  Acetylcholinesterase- an enzyme that breaks down the acetylcholine to prevent overstimulation of muscle fiber. © 2019 McGraw-Hill  4 Neuromuscular Junction 4 Figure © 2019 McGraw-Hill 7.5 (b) ©Ed Reschke/Photolibrary/Getty  4 Muscle Contraction 5 1 1. An action potential travels down motor neuron to presynaptic terminal causing Ca2+ channels to open. 2. Ca2+ causes synaptic vesicles to release acetylcholine into synaptic cleft. 3. Acetylcholine binds to receptor sites on Na+ channels, Na+ channels open, and Na+ rushes into © 2019 McGraw-Hill  Function of the 4 6 Neuromuscular Junction Figure © 2019 McGraw-Hill 7.6  4 Muscle Contraction 7 2 4. Na+ causes sarcolemma and t- tubules to increase the permeability of sarcoplasmic reticulum which releases stored calcium. 5. Ca2+ binds to troponin which is attached to actin. 6. Ca2+ binding to troponin causes tropomyosin to move exposing attachment sites for myosin. © 2019 McGraw-Hill  4 Muscle Contraction 8 3 8. ATP is released from myosin heads and heads bend toward center of sarcomere. 9. Bending forces actin to slide over myosin. 10. Acetylcholinesterase (enzyme breaks down acetylcholine) is released, Na+ channels close, and muscle contraction stops. © 2019 McGraw-Hill  4 Skeletal Muscle Excitation 9 1 Figure 7.8 © 2019 McGraw-Hill (1)  5 Skeletal Muscle Excitation 0 2 Figure 7.8 © 2019 McGraw-Hill (2,3)  5 Skeletal Muscle Excitation 1 3 Figure 7.8 © 2019 McGraw-Hill (4)  5 Skeletal Muscle Excitation 2 4 Figure 7.8 © 2019 McGraw-Hill (5,6)  5 Skeletal Muscle Excitation 3 5 Figure 7.8 © 2019 McGraw-Hill (6,7,8)  5 Skeletal Muscle Excitation 4 6 Figure 7.8 © 2019 McGraw-Hill (9)  5 Muscle 5 Twitch 1  is a single contraction of a muscle fiber in response to a stimulus.  has three phases: latent phase, contraction phase, and relaxation phase. © 2019 McGraw-Hill  5 Muscle 6 Twitch 1 Latent phase  the time between the application of a stimulus and the beginning of contraction. Contraction phase  the time during which the muscle contracts and the Relaxation phase  is the time during which the muscle © 2019 McGraw-Hill  5 Muscle 7 Twitch 2 Figure © 2019 McGraw-Hill 7.10  5 Summation and Recruitment 8 Summation- the individual muscles contract more forcefully. Tetanus is a sustained contraction that occurs when the frequency of stimulation is so rapid that no relaxation occurs. Recruitment is the stimulation of several motor units which increases the total number of muscle fibers contracting. © 2019 McGraw-Hill  5 Multiple-Wave Summation 9 Figure © 2019 McGraw-Hill 7.11  6 Skeletal Muscle Fiber Types 0 1 Slow twitch fibers contract slowly fatigue slowly have a considerable amount of myoglobin use aerobic respiration are dark in color used by long distance runners © 2019 McGraw-Hill  6 Skeletal Muscle Fiber Types 1 2 Fast twitch fibers contract quickly fatigue quickly use anaerobic respiration energy from glycogen light color used by sprinters © 2019 McGraw-Hill  Energy Requirements 6 2 for Muscle Contractions 1. Aerobic production of ATP during most exercise and normal conditions. 2. Anaerobic production of ATP during intensive short-term work 3. Conversion of a molecule called creatine phosphate to ATP 4. Conversion of two ADP to one ATP and one AMP (adenosine © 2019 McGraw-Hill  ATP Production in Resting & Exercise 63 Muscle REST  1. ATP is produced by aerobic respiration  2. Small amounts of ATP are used by muscle contractions that maintain muscle tone  3. Excess ATP is used to produced creatine phosphate © 2019 McGraw-Hill  6 EXERCI 4 SE 4.As exercise begins, ATP already in the muscle cells is used first, but during moderate exercise, aerobic respiration provides most of the ATP necessary for muscle contraction. 5.During times of extreme exercise, anaerobic respiration provides small amount of ATP that can sustain muscle contraction for brief periods. 6.Energy store in creatine phosphate can also be used to produce ATP. 7.Throughout the time of exercise, ATP © 2019 McGraw-Hill  6 Muscle Fatigue 5 1  is a temporary state of reduced work capacity.  Without fatigue, muscle fibers would be worked to the point of structural damage to them and their supportive tissues. © 2019 McGraw-Hill  6 Mechanisms of Fatigue 6  Acidosis and ATP depletion due to increased ATP consumption or a decreased ATP production  Oxidative stress- buildup of excess reactive oxygen species (ROS; free radicals)  Local inflammatory reactions © 2019 McGraw-Hill  6 Types of Contractions 7 1 Isometric contraction  has an increase in muscle tension, but no change in length. Isotonic contraction  has a change in muscle length with no change in tension. © 2019 McGraw-Hill  6 Types of Contractions 8 2 Concentric contractions  are isotonic contractions in which muscle tension increases as the muscle shortens. Eccentric contractions  are isotonic contractions in which tension is maintained in a muscle, but the opposing resistance causes the muscle to lengthen. © 2019 McGraw-Hill  6 9 ISOTONIC ISOMETRIC EXERCISE EXERCISE  There is a  increase in change in muscle tension, muscle but no change length, no in length. change in tension. © 2019 McGraw-Hill  7 Muscle Tone 0  is the constant tension produced by body muscles over long periods of time.  responsible for keeping the back and legs straight, the head in an upright position, and the abdomen from bulging. Disturbance in muscle tone  Atrophy  Flaccidity © 2019 McGraw-Hill  7 1 © 2019 McGraw-Hill  7 Smooth Muscle 2  are non-striated small, spindle- shaped muscle cells, usually with one nucleus per cell.  Contain less actin and the myofilaments are not organized into sarcomeres.  The cells comprise organs controlled involuntarily, except the heart.  Neurotransmitter substances, © 2019 McGraw-Hill  7 Cardiac Muscle 3 1  are long, striated, and branching, with usually only one nucleus per cell.  is striated as a result of the sarcomere arrangement  contraction is autorhythmic. © 2019 McGraw-Hill  7 Cardiac Muscle 4  muscle cells are connected to one another by specialized structures that include desmosomes and gap junctions called intercalated disks.  Cardiac muscle cells function as a single unit in that action potential in one cardiac muscle cell can stimulate action potentials in adjacent cells causing to contract all together. © 2019 McGraw-Hill  7 Arrangement of Fascicles 5 Circular  arranged in concentric rings or in circle around the opening.  Acts as sphincters to open and close the opening  Ex: orbicularis oris, orbicularis oculi © 2019 McGraw-Hill  7 6 © 2019 McGraw-Hill  7 Arrangement of Fascicles 7 Convergent  fascicles converge toward a single insertion tendon  such muscle is triangular or fan- shaped.  Ex: pectoralis major and minor © 2019 McGraw-Hill  7 8 © 2019 McGraw-Hill  7 Arrangement of Fascicles 9 Parallel  the length of the fascicles run parallel to one another to the long axis of the muscle.  Ex: trapezium, quadrate, rhomboidal © 2019 McGraw-Hill  8 0 © 2019 McGraw-Hill  8 1 Pennate  Fascicles originate from a tendon that runs the length of the entire muscle.  Unipennate - fascicles on only one side of the tendon. (Palmar interosseus)  Bipennate- fascicles on both sides of the tendon. (Rectus femoris)  Multipennate- fascicles arranged at many places around the central tendon (deltoid) © 2019 McGraw-Hill  8 2 © 2019 McGraw-Hill  8 3 Fusiform  fascicles lie parallel to long axis of muscle  Ex: biceps brachii, triceps brachii © 2019 McGraw-Hill  8 4 © 2019 McGraw-Hill  8 Skeletal Muscles 5 1 Figure © 2019 McGraw-Hill 7.14a  8 Skeletal Muscles 6 2 Figure © 2019 McGraw-Hill 7.14b  8 Skeletal Muscle Anatomy 7 Tendon - connects skeletal muscle to bone. Aponeuroses- are broad, sheetlike tendons. Retinaculum- is a band of connective tissue that holds down the tendons at each wrist and ankle. Origin – the most stationary, fixed, end of a muscle. Insertion -is the end of the muscle © 2019 McGraw-Hill  8 Skeletal Muscle Anatomy 8 2 Belly  the part of the muscle between the origin and the insertion Agonists  a single or group of muscles working together. Antagonists  a muscle or group of muscles that oppose muscle actions. © 2019 McGraw-Hill  8 9 © 2019 McGraw-Hill  9 0 Synergist  members of a group of muscles working together to produced movement  Brachii and brachialis  Deltoid, biceps brachii, and pectoralis major © 2019 McGraw-Hill  9 Muscle 1 Attachment Figure © 2019 McGraw-Hill 7.13  9 Prime 2 Mover  one muscle plays the major role to accomplish the desired movement.  Ex: Brachialis is the prime mover in flexing the elbow FIXATORS  Are muscles that hold one bone in place  stabilize origin of prime mover  © 2019 McGraw-Hill  9 Nomenclature 3 1 Muscles are named according to: 1. Location – a pectoralis muscle is located in the chest. 2. Size – the size could be large or small, short or long. 3. Shape - the shape could be triangular, quadrate, rectangular, or round. 4. Orientation of fascicles – fascicles © 2019 McGraw-Hill  9 Nomenclature 4 2 5. Origin and insertion. The sternocleidomastoid has its origin on the sternum and clavicle and its insertion on the mastoid process of the temporal bone. 6. Number of heads. A biceps muscle has two heads (origins), and a triceps muscle has three heads (origins). 7. Function. Abductors and adductors © 2019 McGraw-Hill  9 5 Figure 8- 13a © 2019 McGraw-Hill  9 6 Figure 8- 13b © 2019 McGraw-Hill  9 Muscles of the Head and Neck 7  Facial muscles,  Mastication or chewing tongue  Swallowing muscles  Eyes muscles  head and neck muscles © 2019 McGraw-Hill  9 8 Figure 8.14 © 2019 McGraw-Hill  9 Facial Muscles 9 BUCCINATOR  Wall of the cheeks  flattens the cheek (as in whistling or blowing a trumpet)  “Kissing Muscle or Trumpeter’s muscle  Compresses cheek to hold food teeth © 2019 McGraw-Hill  10 0 Depressor anguli oris  Lower corners of mouth/depresses the corner of mouth Levator Labii superioris  Elevates one side of the upper lip OccipitoFrontalis  Moves scalp, raises eyebrows, and to wrinkle your forehead © 2019 McGraw-Hill  10 1 Orbicularis oris  closes the mouth and protrudes the lips,  the “kissing” muscle Orbicularis oculi close the eyes, squint, blink, and wink. Zygomaticus  the “smiling” muscle  elevate the upper lip and © 2019 McGraw-Hill  Muscles of Facial Expression 10 2 and Mastication Figure © 2019 McGraw-Hill 7.16 ©McGraw-Hill Education/  10 CHEWING MUSCLES 3 1.Masseter - closes the jaw by elevating and pushing the mandible anteriorly 2.Temporalis -elevates and draws mandible posteriorly. 3.Ptergoid 4.Lateral- pushes the mandible anteriorly and depresses mandible, close the jaw © 2019 McGraw-Hill  10 Tongue and Swallowing Muscles 4 Tongue Muscles  Intrinsic- change the shape of the tongue  Extrinsic- moves the tongue Hyoid Muscles Suprahyoid (geniohyoid, stylohyoid, hyoglossus)  elevates or stabilized hyoid © 2019 McGraw-Hill  10 Tongue and Swallowing Muscles 5 Figure © 2019 McGraw-Hill 7.17  10 Deep Neck Muscles 6 1. Neck Flexors  originate on the anterior side of the vertebra which flex the head and neck 2. Neck Extensor  originate on the posterior side of the vertebra that extend the head and neck © 2019 McGraw-Hill  10 7 Sternocleidom astoid  Individually rotate the head; together it flex the neck Platysma pull the corners of the mouth inferiorly Trapezius  Extends and laterally flexes the neck © 2019 McGraw-Hill  10 8 Figure 8- 13b © 2019 McGraw-Hill  10 9 Figure 8.14 © 2019 McGraw-Hill  11 Trunk Muscles 0  Vertebral column,  Thorax,  Abdominal wall and  Pelvic floor. © 2019 McGraw-Hill  11 Trunk Muscles 1 Muscles of the Vertebral Column Erector Spinae  Extends vertebral column & maintain posture.  Divides in 3 column; Iliocostalis, longissimus, Spinalis. © 2019 McGraw-Hill  11 Deep Neck and Back Muscles 2 Figure © 2019 McGraw-Hill 7.18  11 3 Deep Back Muscles  Located between spinous and transverse processes adjacent to vertebra  Responsible for movement of vertebral column including extension, lateral flexion and rotation  torn or stretched od these muscles cause sprain and strain. © 2019 McGraw-Hill  11 Thoracic Muscles 4 Scalenes- elevates the ribs, during inspiration External intercostals- elevate ribs for inspiration Internal intercostals- depress ribs during forced expiration Diaphragm- moves during quiet breathing © 2019 McGraw-Hill  11 Muscles of the Thorax 5 Figure © 2019 McGraw-Hill 7.19  11 Abdominal Wall Muscles 6 1 Rectus abdominis  center of abdomen  compresses abdomen External abdominal oblique  sides of abdomen  compresses abdomen © 2019 McGraw-Hill  11 Abdominal Wall Muscles 7 2 Internal abdominal oblique  compresses abdomen Transverse abdominis  compresses abdomen © 2019 McGraw-Hill  11 Muscles of the Anterior Abdominal Wall 8 Figure © 2019 McGraw-Hill 7.20  11 Pelvic Floor Muscles 9 1  Levator ani Perineum Muscles  Ischiocavernosus  Bulbospongiosus  Deep transverse perineal  Superficial transverse perineal © 2019 McGraw-Hill  12 Pelvic Floor Muscles 0 2 Figure © 2019 McGraw-Hill 7.21  12 Muscles Acting on the Scapula 1 Trapezius  shoulders and upper back  extends neck and head  Elevates, depress, retracts, rotates, and fixes scapula Pectoralis minor  Located in the chest  Depresses scapula or elevates ribs © 2019 McGraw-Hill  12 2 2 Serratus anterior between ribs (1-9) Rotates and protracts scapula; elevates ribs Levator scapulae  elevates., retracts, and rotates scapula  Laterally flexes the neck © 2019 McGraw-Hill  12 Muscles Acting on the Scapula 3 Major and Minor Rhomboids  Retracts, rotates, and fixes scapula © 2019 McGraw-Hill  Muscles of the Humerus that Act on the 12 4 Forearm Deltoid Muscle  Flexes and extend shoulder; abducts and medially and laterally rotates the arm Triceps brachii  3 heads, extends elbow, extend shoulders, adducts the arm Biceps brachii  “flexing muscle”, flexes elbow and © 2019 McGraw-Hill  12 5 © 2019 McGraw-Hill  12 6 © 2019 McGraw-Hill  12 Upper Limb Muscles 7 2 Brachialis  flexes elbow Latissimus dorsi  lower back  extends shoulder, adducts and medially rotates the forearm © 2019 McGraw-Hill  12 8 © 2019 McGraw-Hill  12 Arm Muscles 9 Figure © 2019 McGraw-Hill 7.23 (a) ©McGraw-Hill  13 Forearm Muscles 0 Anterior Forearm Muscles 1.Palmaris longus- tightens skin of palm 2.Flexor carpi radialis- flex and abducts wrist 3.Flexor carpi ulnaris- flexes and adducts wrist 4.Flexor digitorum profundus-flex fingers & wrist 5.Flexor digitorum superficialis- © 2019 McGraw-Hill  13 Muscles of the Forearm 1 Figure © 2019 McGraw-Hill 7.24  13 Posterior Forearm Muscle 2 Brachioradialis- flexes the elbow Extensor carpi radialis brevis- extends & abducts wrist Extensor carpi radialis longus- extends & abducts wrist Extensor carpi ulnaris- extends & adducts wrist Extensor digitorum- © 2019 McGraw-Hill  13 Retinacu 3 lum  covers the flexors and extensor tendons and holds them in place around the wrist Intrinsic Hand Muscles  nineteen muscles which are located within the hand Interossei Muscles  located in the metacarpal bones responsible for abduction and adduction of fingers © 2019 McGraw-Hill  13 Muscles of the Forearm 4 Figure © 2019 McGraw-Hill 7.24  13 Muscles of Hips and Thighs 5 Iliopsoas  Anterior muscle that flexes hip Gluteus Maximus  buttocks  extends hip, abducts and laterally rotates the thigh  Not ideal for IM injection © 2019 McGraw-Hill  13 6 Gluteus Medius  abducts and medially rotates the thigh  steadies pelvis during walking  Ideal site of IM injection Tensor Fasciae Latae  A thick band of fascia on the lateral side of the thigh  It helps steady the femur on the tibia when standing © 2019 McGraw-Hill  13 7 © 2019 McGraw-Hill  13 8 © 2019 McGraw-Hill  13 Muscles of the Upper Leg 9 1 Quadriceps femoris is comprised of 4 thigh muscles: 1. Rectus femoris:  front of thigh  extends knee and flexes hip 2.Vastus lateralis:  extends knee 3.Vastus medialis:  extends knee 4.Vastus intermedius: © 2019 McGraw-Hill  14 0 © 2019 McGraw-Hill  14 1 Sartor ius  longest muscle in the body  tailor’s” muscle  it flexed the hip and knee and rotates the thigh laterally for sitting cross legged. © 2019 McGraw-Hill  14 2 © 2019 McGraw-Hill  14 Medial Compartment 3 Adductor Longus  flexes the hip; adducts and laterally rotates the thigh Adductor Magnus  extends the hip; adducts and laterally rotates the thigh Gracilis  adducts thigh and flexes knee © 2019 McGraw-Hill  14 4 © 2019 McGraw-Hill  14 5 Figure 8.23b © 2019 McGraw-Hill  14 Muscles of the Upper Leg 6 2 Hamstring Muscles  back of thigh  flexes knee, rotates leg, extends hip © 2019 McGraw-Hill  14 HAMSTRINGS MUSCLES 7 Biceps femoris  flexes the knee, extend the hip, laterally rotates the leg Semimembranosus  flex knee and extend the hip, medially rotates the leg Semitendinosus  flex knee and extend the hip, medially rotates the leg © 2019 McGraw-Hill  14 8 Adductor Muscles  adducts the thigh © 2019 McGraw-Hill  14 9 Figure 8.23b © 2019 McGraw-Hill  15 Muscles of the Hip and Thigh 0 Figure © 2019 McGraw-Hill 7.26  Muscles Causing Movement at the 151 Ankle and Foot Anterior Compartment Extensor digitorum longus  extends the four lateral toes; dorsiflexes and everts foot Extensor hallucis longus  extend great toes; dorsiflex and © 2019 McGraw-Hill  15 2 Figure 7.8ef © 2019 McGraw-Hill  15 3 Figure 7.8g © 2019 McGraw-Hill  Muscles Causing Movement at the 154 Ankle and Foot Anterior Compartment Tibialis anterior  dorsiflexes and inverts the foot Fibularis/ Peroneus tertius  dorsiflexflexes and everts the © 2019 McGraw-Hill  15 Muscles of Lower Leg 5 Posterior Compartment Gastrocnemius  calf  plantarflexes the foot; flexes the leg  “toe dancer’s” muscle Soleus  attaches to ankle  Plantar flexes the foot © 2019 McGraw-Hill  15 6 Figure 7.8g © 2019 McGraw-Hill  15 Lower Leg Muscles 7 Figure © 2019 McGraw-Hill 7.28 (d) ©Eric  15 8 Lateral Compartment Muscles Fibularis/Peroneus (longus,  brevis,) Plantar flexes and everts the foot © 2019 McGraw-Hill  15 Effects of Aging In 9 Muscles  Reduction in muscle mass  Slower response time for muscle contraction  Reduced stamina  Increased Recovery time © 2019 McGraw-Hill  Diseases and Disorders of Muscular System 160 Cramps  painful spastic contraction of muscle due to build up of lactic acid Fibromyalgia  chronic widespread pain in muscles with no known cause © 2019 McGraw-Hill  16 Hypertrophy 1  enlargement of a muscle due to increased myofibrils due to increased muscle used Atrophy  decreased in muscle size due to decreased myofibrils because of disuse muscle as in paralysis Tendinitis  inflammation of a tendon or its attachment joint due to overuse of a muscle © 2019 McGraw-Hill  16 Muscular dystrophy 2  a group of inherited muscle- destroying disease that affect muscle group.  The most common & serious form is Duchenne’s muscular dystrophy. © 2019 McGraw-Hill  16 Duchenne Muscular Dystrophy 3  results from abnormal gene on the X chromosome  The gene is carried by female but DMD common on males  DMD gene is responsible for producing a protein called DYSTROPIN © 2019 McGraw-Hill  16 DMD 4  part of the gene is missing and the protein in produces is nonfunctional resulting to progressive muscular weakness and muscular contractures. © 2019 McGraw-Hill  16 SYMPTOMS 5  Muscular weakness  Muscle atrophy  Contractures © 2019 McGraw-Hill  16 6 Nervo us  Mental retardation Cardiovascualr Affects cardiac muscles leading heart failure Respiratory  Weakness of the respiratory muscles leading to respiratory failure © 2019 McGraw-Hill  16 7 Digest ive  Affects smooth muscle and reduce the ability of smooth muscle to contract Urinary  Reduced smooth muscle function  Increase UTI © 2019 McGraw-Hill  16 8 Skele tal  Shortened inflexible muscles  Kyphoscoliosis- sever curvature of the vertebra laterally or anteriorly  Wheelchair dependency © 2019 McGraw-Hill  Duchenne Muscular 16 9 Dystrophy © 2019 McGraw-Hill  17 0 Treatm ent  Physical therapy primarily involves exercise  No effective treatment to prevent © 2019 McGraw-Hill Myasthenia 17 1 Gravis  characterized by drooping of the upper eyelid difficulty of swallowing & talking and generalized muscle weakness and fatigability.  Death occurs as a result of the inability of the respiratory muscle to function (respiratory failure). © 2019 McGraw-Hill  17 2 © 2019 McGraw-Hill  17 3 © 2019 McGraw-Hill  17 4 © 2019 McGraw-Hill