Musculoskeletal System Anatomy PDF

ANATOMY II-NURSING & MIDWIFERY 6/30/2022 PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System 1...

ANATOMY II-NURSING & MIDWIFERY 6/30/2022 PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System 1 MR. BRIGHT OWUSU Department of Nursing and Midwifery Faculty of Health and Allied Sciences (FHAS) Pentecost University College UNIT TWO: MUSCULOSKELETAL SYSTEM 6/30/2022 PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System TOPICS: 1. Introduction 2. Explain the purpose of the musculoskeletal system 3. The Skeletal System 4. The Muscular System 2  INTRODUCTION: THE MUSCULOSKELETAL SYSTEM 6/30/2022  The musculoskeletal system (also known as the locomotor system) is an organ system that enables an organism to move, support itself, and maintain stability during locomotion. PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System ― it provides form, support, stability, protection (of vital organs), and movement to the body.  The musculoskeletal system consists of the; ― muscular system and ― skeletal system  The musculoskeletal system is made up of the body’s; ― bones (the skeleton), muscles, cartilage, tendons, ligaments, joints, and 3 ― other connective tissue that supports and binds tissues and organs together  The Musculoskeletal System cont.  Its primary functions thus include; 6/30/2022 ― bones of the skeletal system provide stability and protection to the body ― muscles keep bones in place and also play a role in their movement ― tendons, ligaments and fibrous tissue bind the structures together to PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System create stability ― ligaments connecting bone to bone, and ― tendons connecting muscle to bone.  To allow for motion, ― different bones are connected by articulating joints, and ― cartilage prevents the bone ends from rubbing directly onto each other 4 SECTION 2: THE SKELETAL SYSTEM 6/30/2022  Chapter Objectives: By the end of this section, you will be able to: PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  Overview of the Skeleton ― Bones of the Skeletal System ― Surface Features of Bones  The Skull  The Vertebral Column and Thoracic Cage  The Pectoral Girdle and Upper Limb  The Pelvic Girdle and Lower Limb 5  Introduction to the Skeletal System The skeletal system is composed of … PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  6/30/2022 ― Bones; support the weight of the body,  allow for body movements, and  protect internal organs. ― Cartilages; provides flexible strength and support for body structures such as the thoracic cage, the external ear, and the trachea and larynx.  at joints of the body, cartilage can also unite adjacent bones or provide cushioning between them. ― Ligaments; are the strong connective tissue bands that hold the bones at a moveable joint together and 6  serve to prevent excessive movements of the joint that would result in injury The Functions of the Skeletal System 6/30/2022 PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  The skeletal system performs the following critical functions for the human body: ─ forms the framework of the body 7  Module 1: Integumentary System 6/30/2022 PU: FHAS - Nursing & Midwifery L100 8 Terminologies  Organization of the Skeletal System 6/30/2022  The skeleton is divided into …. PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System ― Axial skeleton: skull, vertebrae, sternum, ribs, sacrum, ear ossicles and hyoid bone ― Appendicular skeleton: pectoral girdle, upper extremity, pelvic girdle, lower extremity 9  The Axial Skeleton  The axial skeleton consists of …. ― the bones that form the central bony core of the body (the axis) ― support and protect the organs of the head (brain), neck, and trunk (spinal cord, heart, and lungs) ― it also serves as the attachment site for muscles that move the head, neck, back, shoulder and hip joints  The axial skeleton of the adult consists of 80 bones, comprising the … ― skull, ― vertebral column (including sacrum), and ― the thoracic cage (including sternum, ribs) ― also associated with the head are the hyoid bone and the ear ossicles 10  The Skull PU: FHAS - Nursing & Midwifery L100 Module  The skull rests on the upper end of the vertebral column 6/30/2022 1: Integumentary System ― it’s the most complex part of the skeleton ― in the adult, the skull consists of 22 individual bones  The skull’s bony structure is divided into two parts: ― cranial bones (8 bones); surround cranial cavity which encloses the brain ― facial bones (14 bones); support teeth, facial and Figure: Parts of the Skull: The skull jaw muscles consists of the rounded cranium that houses the brain and the facial bones that form the upper and lower jaws, nose, orbits,  Each bone of the skull articulates with the adjacent and other facial structures. bones 11  foramina are holes that allow passage for nerves and blood vessels  Module 1: Integumentary System 6/30/2022 PU: FHAS - Nursing & Midwifery L100 12 The Skull 13  Functions of the Skull  The various parts of the skull have specific and different functions: 6/30/2022 ― the cranium protects the delicate tissues of the brain. ― the bony eye sockets provide the eyes with some protection against injury and give attachment to the muscles that move PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System the eyes. ― the temporal bone protects the delicate structures of the ear. ― the sinuses in some face and skull bones give resonance to the voice. ― the bones of the face form the walls of the posterior part of the nasal cavities and form the upper part of the air passages. ― the maxilla and the mandible provide alveolar ridges in which the teeth are embedded. 14 ― the mandible, controlled by muscles of the lower face, allows chewing of food  Sutures of the Skull  A suture is an immobile joint (dense fibrous connective tissue ) between adjacent bones of the 6/30/2022 skull. PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  The long sutures are not straight, ― but instead follow irregular, tightly twisting paths.  serve to tightly interlock the adjacent bones,  thus adding strength to the skull to protect the brain.  There are four major cranial sutures formed between the various bones of the skull: 15  Skull in Infancy and Childhood  Fontanels are spaces between unfused bones 6/30/2022 ― filled with fibrous membrane ― permit the skull to undergo changes in shape ( called molding) during parturition (childbirth), PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System ― they accommodate the rapid growth of the brain during infancy  The fontanels include; ― anterior (frontal; most prominent), posterior (occipital), sphenoid (anterolateral; on both sides of the skull), and mastoid (posterolateral; on both sides of the skull) fontanels  Ossification of the fontanels is normally complete by 20 to 24 months of age. 16  Skull reaches adult size by 8 or 9 years of age  PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System Paranasal Sinuses  Four sets of paranasal sinuses are located within the skull bones (frontal, sphenoid, ethmoid, and maxillary) surrounding the nasal area ― they communicate via ducts into the nasal cavity.  The paranasal sinuses are named for the bones in which they occur; the ― frontal, sphenoid, ethmoid, and maxillary (larger in volume) sinuses ― lined by mucous membrane ― are filled with air ― lighten the anterior portion of the skull ― act as chambers that add resonance to 17 the voice The Vertebral Column (Spine) 6/30/2022  General Features:  The vertebral column consists of … ― a series of irregular bones called vertebrae, PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System ― separated from each other by fibrocartilaginous intervertebral discs. ― and are secured to each other by interlocking processes and binding ligaments.  The vertebral column is subdivided into five regions; ― 7 cervical in the neck ― 12 thoracic in the chest ― 5 lumbar in lower back ― 5 fused sacral at base of spine 18 ― 4 fused coccygeal  The Vertebral Column cont.  General Features cont.: 6/30/2022  The vertebral column is typically (in embryo) composed of 33- 34 individual vertebrae, some of which are fused PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System ― 5 fuse to form sacrum ― 3 or 5 coccygeal fuse to form the coccyx  The adult vertebral column is composed of a total of 26 movable parts (bones) in the vertebral column. ― 24 separate vertebrae extend downwards from the occipital bone of the skull; then there is ― the sacrum, formed from five fused vertebrae ― the coccyx, or tail, which is formed from between three to five small fused vertebrae. 19  Curvatures of the Vertebral Column  Adult Spinal Curvatures: 6/30/2022  The adult vertebral column does not form a straight line, but instead has four curvatures PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System along its length (s-shaped vertebral column). 1. Cervical: anterior 2. Thoracic: posterior 3. Lumbar: anterior 4. Pelvic (Sacral and coccygeal): posterior  These curves increase the vertebral column’s ― strength, flexibility, and ― ability to absorb shock. 20  Curvatures of the Vertebral Column cont. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Newborn Spinal Curvature: 6/30/2022   At birth, spine exhibits one continuous C-shaped PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System curve ― known as primary curvature (thoracic and sacrococcygeal curves) ― lifting head as the baby begins to crawl develops cervical curvature ― when sitting and walking begin, lumbar curve develops 21 © The McGraw-Hill Companies, Inc./Bob Coyle, photographer  Abnormal Spinal Curvatures Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 6/30/2022  From disease, paralysis of trunk muscles, poor posture, pregnancy, or congenital defect PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  Scoliosis – abnormal lateral curvature, accompanied by twisting of the vertebral column ― usually in thoracic region ― developmental abnormality in which the body and arch fail to develop on one side of the vertebrae (a) Scoliosis (b) Kyphosis (c) Lordosis Key (“hunchback”) (“hunchback”) Normal Pathological 22  Abnormal Spinal Curvatures cont.  kyphosis (hunchback) – exaggerated or excessive posterior curvature of the thoracic region ― usually from osteoporosis, also osteomalacia or spinal tuberculosis, or wrestling or weightlifting in young boys  lordosis (swayback) – exaggerated or excessive anterior curvature of the lumbar region ― most commonly associated with obesity or late pregnancy and weak abdominal muscles Figure: Abnormal Curvatures of the Vertebral Column: 23 (a) Scoliosis is an abnormal lateral bending of the vertebral column. (b) An excessive curvature of the upper thoracic vertebral column is called kyphosis. (c) Lordosis is an excessive curvature in the lumbar region of the vertebral column General Structure of Vertebra  Body (centrum) ― mass of spongy bone that contains red bone marrow 6/30/2022 ― weight bearing portion ― rough superior and inferior surfaces provide firm PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System attachment for intervertebral discs  Vertebral foramina ― hole in each vertebra ― collectively form vertebral canal for spinal cord  Intervertebral notches ― Form intervertebral foramina between two adjacent vertebrae through which spinal 24 nerves exit the vertebral canal  Intervertebral Disks Located between adjacent vertebrae 6/30/2022  ― first one between C2 and C3 ― last one between L5 and sacrum PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  Functions ― provide support ― prevent vertebrae rubbing against each other ― bind vertebrae together ― support weight of the body ― absorb shock  Becomes compressed with age and height decreases  With age, more susceptible to herniation (‘ruptured’ or ‘slipped’ disc; herniated Disc) 25 ― puts painful pressure on spinal nerve or spinal cord  Cervical vertebrae  Atlas: first cervical vertebra 6/30/2022 ― is the bone on which the skull rests ― articulates with the oval PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System occipital condyles of the skull (atlanto-occipital joint) and permits the nodding of the head in a “yes” movement.  Axis: second cervical vertebra ― small body and larger vertebral foramen ― dens or odontoid process extends superiorly into the vertebral foramen of the atlas; atlantoaxial joint 26 ― allows rotation of the atlas on the axis, the “no” movement (turning the head from side to side)  Thoracic Cage  Functions: ― Protects thoracic organs (lungs and heart,  but also the spleen, most of the liver, and to some extent the kidneys ― Forms semi-rigid chamber for respiration PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  rhythmically expanded by respiratory muscles to draw air into the lungs ― provides attachment for pectoral girdle and upper limbs  Parts: ― Thoracic vertebrae ― Sternum (breastbone) 27 ― Ribs (12 pair)  The Appendicular Skeleton Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.  The appendicular skeleton consists of the … ― Girdle 6/30/2022  Pectoral or shoulder  Pelvic PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System ― Upper Limbs  Arm  Forearm  Wrist  Hand ― Lower Limbs  Thigh  Leg  Foot 28  The appendicular skeleton consists oof 126 bones  The Pelvic Girdle PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  The pelvic girdle consists of a 6/30/2022 complete ring composed of three bones ― two hip (coxal) bones  also called ossa coxae or innominate bones ― sacrum that is also part of the vertebral column  The Pelvis is a bowl-shaped structure composed of the two coxal bones and sacrum as well as their ligaments and muscles that line the pelvic cavity and form its floor ― supports trunk on the lower limbs and protects viscera, lower colon, urinary bladder, and internal reproductive organs  Sacroiliac joint: joins hipbone to the vertebral column 29  Interpubic disc: pad of fibrocartilage joins pubic bones  Pubic symphysis: the interpubic disc and adjacent regions of the pubic bone on each side Comparison of Male and Female 6/30/2022  Male: heavier and thicker due to forces exerted by stronger muscles  Female: wider and shallower, and  adapted to the needs of pregnancy and childbirth,  larger pelvic inlet and outlet 30 for passage of infant’s head  Bones of the Skeletal System  Bone (osseous tissue) - connective tissue with the matrix 6/30/2022 hardened by calcium phosphate and other minerals ― are highly vascular living structures that are continuously being remodeled PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  Mineralization or calcification – the hardening process of bone  Individual bones consist of bone tissue, bone marrow, cartilage, adipose tissue, nervous tissue, and fibrous connective tissue ― permeated with nerves and blood vessels, which attests to its sensitivity and metabolic activity  Each bone is actually an organ that plays a part in the total functioning of the 31 skeletal system.  Types or Shapes of bones  Different types of bones have differing shapes related to their particular function.  Long bones; support the weight of the body and facilitate movement PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  longer than wide  rigid levers acted upon by muscles  Short bones; provide stability and some movement  are about as long as they are wide  glide across one another in multiple directions  Flat bones; protect soft organs  curved but wide & thin  Irregular bones  elaborate shapes that don’t fit into the other categories  Sesamoid: small, round bones embedded in tendons of the hands, knees, and feet 32  protect tendons from stress and wear  General Features of Bones Part Description Diaphysis Cylinder (shaft) of compact bone to provide leverage Epiphysis Enlarged spongy ends of a long bone; develops from a center 6/30/2022 of ossification distinct from the diaphysis enlarged to strengthen joint and attach ligaments and tendons PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System Periosteum Double-layered connective tissue membrane (external sheath) covering the outer surface of bone except where articular cartilage is present; ligaments and tendons attach to bone through the periosteum; blood vessels and nerves from the periosteum supply the bone; the periosteum is where bone grows in diameter Endosteum Thin connective tissue membrane lining the inner cavities (marrow) of bone Articular a thin layer of hyaline cartilage that covers the joint surface cartilage where one bone meets another allows joint to move more freely and relatively friction free 33 Nutrient Minute holes in the bone surface that allows blood vessels to foramina penetrate Part Description General Features of Bones cont. Epiphyseal Area of hyaline cartilage that separates the marrow spaces of plate (growth the diaphysis and epiphysis; plate) cartilage growth followed by endochondral ossification results in growth in bone length 6/30/2022 epiphyseal line – in adults, a bony scar that marks where growth plate used to be Spongy Bone having many small spaces; PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System (cancellous) covered by more durable compact bone bone found mainly in the epiphysis, and the middle of nearly all other bones skeleton is about three-fourths compact and one-fourth spongy bone by weight Compact bone Dense bone with few internal spaces organized into osteons; forms the diaphysis (outer shell) and covers the spongy bone of the epiphyses Medullary Large cavity within the diaphysis of a long bone that contains (marrow) cavity bone marrow Red marrow Connective tissue in the spaces of spongy bone or in the medullary cavity; the site of blood cell production 34 Yellow marrow Fat stored within the medullary cavity or in the spaces of spongy bone  Histology of Osseous Tissue Bone is connective tissue that consists of 6/30/2022  cells, fibers and ground substance  Four principal types of bone cells PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System a. osteogenic (osteoprogenator) cells: stem cells found in endosteum, periosteum, and in central canals ─ multiply continuously to produce new osteoblasts b. Osteoblasts: bone forming cells; synthesize soft organic matter of matrix which then hardens by mineral deposition c. Osteocytes: former osteoblasts that have become trapped in the matrix they have deposited; d. Osteoclasts: bone-dissolving cells found on the bone surface 35  Bone remodeling results from combined action of the bone-dissolving osteoclasts and the bone-depositing osteoblasts  Histology of Osseous Tissue cont.  Trabeculae: interconnecting rods or plates of bone; like scaffolding. 36 ─ spaces filled with marrow  Bone Development o Ossification or osteogenesis – the formation of bone ─ in the human fetus and infant, bone develops by two methods 6/30/2022 o Intramembranous ossification ─ takes place in connective tissue membrane PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System ─ forms many skull bones, part of mandible, diaphyses of clavicles o Endochondral ossification ─ takes place in cartilage ─ cartilage formation begins at end of fourth week of development ─ some ossification beginning at about week eight; some does not begin until 18- 20 years of age ─ bones of the base of the skull, part of the mandible, epiphyses of the clavicles, and most of remaining bones of skeletal system o Both methods of ossification 37 ─ produce woven bone that is then remodeled ─ after remodeling, formation cannot be distinguished as one or other  Module 1: Integumentary System 6/30/2022 PU: FHAS - Nursing & Midwifery L100 38 Endochondral Ossification Growth in Bone Length  Growth in length occurs 6/30/2022 at the epiphyseal plate ─ involves the formation of new PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System cartilage  Closure of epiphyseal plate: epiphyseal plate is ossified becoming the epiphyseal line. ─ between 12 and 25 years of age  Articular cartilage: does not ossify, and persists through life 39  Bone Repair Clot formation: Internal - blood vessels grow into clot in hematoma. confined within Macrophages clean up debris, osteoclasts break down dead tissue, fibroblasts produce an organ or collagen and granulation tissue. space. Chondroblasts from osteochondral progenitor cells of periosteum and endosteum produce cartilage within the collagen. 40 Osteoblasts invade; new bone is formed. External - collar around opposing ends. Cells; periosteal osteochondral progenitor cells osteoblasts and chondroblasts. Bone/cartilage collar stabilizes two pieces.  Effects of Aging on Skeletal System  Bone matrix decreases. ─ become more brittle due to lack of collagen 6/30/2022  Bone mass decreases. PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System ─ highest around 30.  men denser due to testosterone and greater weight. ─ rate of bone loss increases 10 fold after menopause.  spongy bone lost first, then compact.  Increased bone fractures  Bone loss causes deformity, loss of height, pain, stiffness ─ stooped posture ─ loss of teeth 41  Module 1: Integumentary System 6/30/2022 PU: FHAS - Nursing & Midwifery L100 42 When things go wrong  SECTION 2 : THE SKELETAL SYSTEM CONT. ARTICULATIONS (JOINTS) AND MOVEMENT 6/30/2022  Chapter Objectives: PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System By the end of this section, you will be able to:  Discuss both functional and structural classifications for body joints  Define and identify the different body movements  Discuss the structure of specific body joints and the movements allowed by each  Explain the development of body joints 43 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.  Introduction to Joints PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  Joints (articulation) are the location where 6/30/2022 adjacent bones or bone and cartilage come together (articulate with each other) to form a connection. ─ joints hold the skeleton together and support movement. ─ whether or not the bones are movable at that interface  Joint stability and movement are related to each other ─ stable joints allow for little or no mobility between the adjacent bones ─ conversely, joints that provide the most movement between bones are the least stable. 44  Introduction to Joints cont.  Arthrology – science of joint structure, function, and dysfunction  Kinesiology – the study of musculoskeletal movement  Joint name – typically derived from the names of the bones involved. Examples; ― atlanto-occipital joint; the synovial articulation between the occipital bone and the first cervical vertebra (atlas) ― glenohumeral (shoulder) joint; articulation between the glenoid of the scapula and the proximal humerus ― radioulnar joint; are two locations (Proximal & Distal ) in which the radius and ulna articulate in the forearm 45  Classification of Joints  Joints in the human skeleton can be grouped by …. ─ function (range of motion): 6/30/2022  differences in how freely the bones can move structure (material): the material that holds the bones of PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System ─ the joints together  the manner in which the adjacent bones are bound to each other  Four major joint categories: ─ fibrous joints (no movement) ─ cartilaginous joints (some movement) ─ synovial joints (full movement)  The relationship between joint structure and function explain why particular types 46 of joints are found in certain areas of the body.  Fibrous Joints PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System 6/30/2022  Between the articulations of fibrous joints is thick connective tissue (collagen fibers), ─ which is why most (but not all) fibrous joints are immovable (synarthroses).  There are three types of fibrous joints: 1. Sutures: are nonmoving joints that connect bones of the skull. ― these joints have serrated edges that lock together with fibers of connective tissue; opposing bones interdigitate 2. Gomphoses: the immovable fibrous articulations between the teeth and the mandible or maxilla 47  Fibrous Joints cont. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System 6/30/2022 3. Syndesmosis: a joint in which a ligament connects two bones, allowing for a little movement (amphiarthroses).  Examples: radioulnar syndesmosis 48 ─ the distal joint between the tibia and fibula  Cartilaginous Joints PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  Cartilaginous Joints are joints that unite 6/30/2022 bones with cartilage.  There are two types of cartilaginous joints: 1. Synchondrosis: is an immovable hyaline cartilaginous joint. ― Example: the joint between the first pair of ribs and the sternum; epiphyseal plate 2. Symphysis: consists of a compressable fibrocartilaginous pad that connects two bones. ― allows for some movement. ― Example: the hip bones, connected by the pubic symphysis, and the 49 vertebrae, connected by intervertebral discs  Module 1: Integumentary System 6/30/2022 PU: FHAS - Nursing & Midwifery L100 50  Synovial joints  Synovial joints are diarthrosis (freely movable) or PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System diarthrodial joints in which two bones are separated by 6/30/2022 a space called a joint (articular) cavity ― most familiar type of joint  Characterized by the …  presence of an articular capsule between the two joined bones. ― connective tissue that encloses the cavity and retains the fluid  synovial fluid; slippery lubricant in joint cavity ― rich in albumin and hyaluronic acid  gives it a viscous, slippery texture like raw egg whites ― nourishes articular cartilage and removes waste 51 ― makes movement of synovial joints almost friction free  Synovial joints cont.  the bone surfaces are protected by a coating of articular cartilage. PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System 6/30/2022 ―provides smooth surface  Synovial joints are often supported and reinforced by surrounding ligaments, ―which limit movement to prevent injury.  No blood vessels or nerves in articular cartilages; ― nutrients are obtained from nearby blood vessels and synovial fluid  Nerves in capsule help brain know position of joints (proprioception) 52  Synovial joints cont.  There are six types of synovial joints: 1. Gliding (plane) joints move 6/30/2022 against each other on a single plane (uniaxial). ― major gliding joints include the PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System intervertebral joints and the bones of the wrists and ankles. 2. Saddle joint allows for flexion, extension, and other movements, but no rotation. ― Biaxial (occurring around two axes at right angles to each other) 3. Hinge joints move on just one axis. 53 ― allow for flexion and extension. ― major hinge joints include the elbow, ankle, and interphalangeal joints.  Synovial joints cont. 4. Pivot joint provides rotation around a single axis. 6/30/2022 ― Example: articulation between dens of axis and atlas (atlantoaxial) at the top of the PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System spine allows for rotation of the head. 5. Ball-and-socket joint is a freely moving joint that can rotate on any axis (multiaxial). ― Example: hip and shoulder joints. 6. Ellipsoid (condyloid) joint is a modified ball-and-socket; ― articular surfaces are ellipsoid 54 ― biaxial; allows for circular motion, flexion, and extension. ― Example: atlantooccipital  Effects of Aging on Joints 6/30/2022  Tissue repair slows; rate of new blood vessel development decreases Articular cartilages wear down and matrix becomes more rigid PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System   Production of synovial fluid declines  Ligaments and tendons become shorter and less flexible: decrease in range of motion (ROM)  Muscles around joints weaken  A decrease in activity causes less flexibility and decreased ROM 55  Module 1: Integumentary System 6/30/2022 PU: FHAS - Nursing & Midwifery L100 56 When things go wrong  When things go wrong cont.  Rheumatoid arthritis (RA): 6/30/2022 autoimmune attack against the joint tissues  misguided antibodies (rheumatoid PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System factor) attack synovial membrane, enzymes in synovial fluid degrade the articular cartilage, joint begins to ossify  ankylosis – solidly fused, immobilized joint 57  Knee Injuries and Disorders  Football injuries: often tear the tibial collateral ligament, the anterior cruciate ligament, and damage the medial meniscus  Chondromalacia: softening of cartilage due to abnormal movement of the patella or to accumulation of fluid in fat pad posterior to patella  Hemarthrosis: acute accumulation of blood in joint 58  When things go wrong cont. 6/30/2022  Arthroplasty - the PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System replacement of diseased joint with artificial device called prosthesis 59  SECTION 3: MUSCULAR SYSTEM 6/30/2022  Chapter Objectives: PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System By the end of this section, you will be able to:  Structural and functional organization of muscles  Muscles of the head and neck  Muscles of the trunk  Muscles acting on the shoulder and upper limb  Muscles acting on the hip and lower limb 60 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.  Organization of Muscles 6/30/2022  Three kinds of muscle tissue  skeletal, cardiac, smooth PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  About 600 human skeletal muscles  Constitute about half of our body weight  Specialized for one major purpose  converting the chemical energy in ATP into the mechanical energy of motion  Myology is the study of the muscular system 61  The Functions of Muscles 6/30/2022  Movement  move from place to place, movement of body parts and body contents in breathing, circulation, feeding and digestion, defecation, urination, and childbirth PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  role in communication – speech, writing, and nonverbal communications  Stability  maintain posture by preventing unwanted movements  antigravity muscles – resist the pull of gravity and prevent us from falling or slumping over  stabilize joints  Control of openings and passageways  sphincters – internal muscular rings that control the movement of food, bile, blood, and other materials 62  Heat production by skeletal muscles  as much as 85% of our body heat  Characteristics of Muscle 6/30/2022  Responsiveness (excitability)  to chemical signals, stretch and electrical changes across the plasma membrane  Conductivity PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  local electrical change triggers a wave of excitation that travels along the muscle fiber  Contractility  ability of a muscle to shorten with force  Extensibility  capable of being stretched between contractions  Elasticity  ability of muscle to recoil to original resting length after stretched 63  Types of Muscle Tissue Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. TABLE 9.1 Comparison of Muscle Types Skeletal Muscle Smooth Muscle Cardiac Muscle 6/30/2022 Location Attached to bones Walls of hollow organs, blood vessels, Heart eyes, glands, and skin Appearance PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System Cell Shape Very long and cylindrical (1 mm–4 cm, or Spindle-shaped (15–200 μm in length, Cylindrical and branched (100–500 μm in as much as 30 cm, in length, 10 μm–100 μm 5–8 μm in diameter) length, 12–20 μm in diameter) in diameter) Nucleus Multiple nuclei: peripherally located Single, centrally located Single, centrally located Special Cell-to-Cell Gap junctions join some visceral smooth Attachments None Intercalated disks join cells to one another muscle cells together Striations Yes No Yes Control Voluntary and involuntary (reflexes) Involuntary Involuntary Capable of Spontaneous No Yes (some smooth muscle) Yes Contraction Function Moving food through the digestive tract, Pumping blood; contractions provide the Body movement emptying the urinary bladder, regulating major force for propelling blood through blood vessel diameter, changing pupil size, blood vessels contracting many gland ducts, moving 64 hair, and having many other functions Characteristics of Smooth Muscle 6/30/2022 PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  no visible striations ─ reason for the name ‘smooth muscle’ 65  Injured smooth muscle regenerates well  Characteristics of Cardiac Muscle  Found only in heart where it functions to pump blood 6/30/2022  Composed of myocytes (cardiocytes) that are shorter and thicker ─ striated like skeletal muscle ─ have gap junctions– intercalated discs  Can contract without need for nervous stimulation ─ contains a built-in pacemaker that rhythmically sets off a wave of electrical excitation ─ wave travels through the muscle and triggers contraction of heart chambers ─ autorhythmic – because of its ability to contract rhythmically and independently  Damaged cardiac muscle cells repair by fibrosis 66 ─ a little mitosis observed following heart attacks ─ not in significant amounts to regenerate functional muscle  Skeletal Muscle Structure  Composed of muscle cells (fibers), connective tissue, 6/30/2022 blood vessels, nerves ─ attached to one or more bones  Fibers are long, cylindrical, multinucleated  Striations: alternating light and dark transverse bands ─ results from overlapping of internal contractile proteins  Voluntary: usually subject to conscious control  Repair by fibrosis rather than regeneration of 67 functional muscle  Module 1: Integumentary System 6/30/2022 PU: FHAS - Nursing & Midwifery L100 68 Skeletal Muscle Structure cont.  Muscle Origins and Insertions  Origin 6/30/2022 ─ bony attachment at stationary end of muscle PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  Belly ─ thicker, middle region of muscle between origin and insertion  Insertion ─ bony attachment to mobile end of muscle 69  Module 1: Integumentary System 6/30/2022 PU: FHAS - Nursing & Midwifery L100 70 Muscular System Anatomy  Muscles of Chewing 6/30/2022  Four pairs of muscles produce the biting and chewing movements of the mandible ─ temporalis, masseter, ─ medial pterygoid, lateral pterygoid 71  innervated by mandibular nerve which is a branch of the trigeminal (V) Muscles of the Eye 6/30/2022  Rectus muscles: ─ Move eyeball and ─ thus pupil laterally, PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System superiorly, inferiorly, and medially  Oblique muscles: ─ both laterally deviate the eyeball. 72  Module 1: Integumentary System 6/30/2022 PU: FHAS - Nursing & Midwifery L100 73 Muscles of Respiration Muscles of the Anterior Abdominal Wall  Four pairs of sheet like muscles: strengthen abdominal wall ─ external abdominal oblique; flexes and rotates abdomen ─ internal abdominal oblique; flexes and rotates abdomen ─ transverse abdominal; compresses abdominal wall ─ rectus abdominis (linea alba, rectus sheath); flexes vertebral column 74 Muscles of the Pelvic Floor  Three layers of muscles and fasciae that span pelvic outlet ─ penetrated by anal canal, urethra, and vagina PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System  Perineum: diamond-shaped region between the thighs ─ urogenital triangle; anterior half of perineum ─ anal triangle; posterior half of perineum 75  Muscles of the Pelvic Floor  Examples of muscles found in the perineum include; ─ Ischiocavernosus; maintains erection of clitoris & penis 6/30/2022 ─ Bulbospongiosus; aids in erection, expels remaining urine ─ Superficial transverse perineal; not always present ─ levator ani: supports viscera and defecation PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System ─ coccygeus: supports and elevates pelvic floor 76  Effects of Aging on Skeletal Muscle 6/30/2022  Reduced muscle mass  Increased time for muscle to contract in response to nervous PU: FHAS - Nursing & Midwifery L100 Module 1: Integumentary System stimuli  Reduced stamina  Increased recovery time  Loss of muscle fibers  Decreased density of capillaries in muscle 77  Module 1: Integumentary System 6/30/2022 PU: FHAS - Nursing & Midwifery L100 78