Skeletal System PDF

SKELETAL SYSTEM MARY JUDITH S. REBOSA, M.D., FPPS OUR LADY OF FATIMA UNIVERSITY  SKELETAL Relate the histology and functions of the bone and other components of the skeletal system to real life situations. identify and classify the different bones that make up...

SKELETAL SYSTEM MARY JUDITH S. REBOSA, M.D., FPPS OUR LADY OF FATIMA UNIVERSITY  SKELETAL Relate the histology and functions of the bone and other components of the skeletal system to real life situations. identify and classify the different bones that make up the body SKELETAL SYSTEM CONSISTS OF CONNECTIVE TISSUE: Bone Cartilage Tendons ligaments BONE HISTOLOGY.  EXTRACELLULAR MATRIX COMPONENTS Collagen – flexible strength ground substance organic molecules water and minerals EXTRACELLULAR MATRIX COLLAGEN Tough ropelike protein For flexible strength 90% of organic content PROTEOGLYCANS Polysaccharide attached to core proteins Attract large amounts of water between polysaccharides EXTRACELLULAR MATRIX TENDONS AND LIGAMENTS Large amount of Collagen fibers CARTILAGE Collagen – toughness PROTEOGLYCANS Smoothness and resilience EXTRACELLULAR MATRIX BONE Collagen – flexible strength Minerals – compression ( weight bearing ) strength Calcium Phosphate Hydroxyapatite – calcium phosphate crystals GROUND SUBSTANCE Water Inorganic minerals Organic substances Extracellular fibers INORGANIC MINERALS WEIGHT BEARING STRENGTH Calcium Phosphorus ( calcium hydroxyapatite crystals ) – large bulk Bicarbonate, citrate, magnesium, potassium, sodium  BONE TISSUE BONE MATRIX arranged in thin layers : LAMELLAE LACUNAE – cavities occupied by osteocytes CANALICULI – ENDOSTEUM Lines the medullary, marrow and vascular cavities PERIOSTEUM Contains blood vessels and nerves TYPES OF BONES SPONGY BONE ( CANCELLOUS ) COMPACT BONE ( CORTICAL; DENSE ) HAVERSIAN SYSTEM SPONGY BONES Consists of : TRABECULAE OR SPICULES Add strength without the added weight Consists of several lamellae with osteocytes between them No blood vessels Red bone marrow Occupies spaces between trabeculae More porous Has less bone matrix  BONE CELLS Osteoprogenitor cells Osteoblasts Osteocytes Osteoclasts https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Book%3A_General_Biolog y_(Boundless)/38%3A_The_Musculoskeletal_System/38.2%3A_Bone/38.2B%3A_Cell_Types_in_Bone s BONE CELLS OSTEOPROGENITOR CELLS Differentiate into osteoblasts or chondroblasts  Osteoblasts Differentiate from osteoprogenitor cells Active in bone formation and repair Aid osteoclasts in bone resorption Transform into osteocytes  OSTEOCYTE Occupy the lacunae in bone tissue Principal cells of mature bones Maintains surrounding matrix  OSTEOCLAST Large multinucleated cells on the surfaces of bone Agent of bone resorption or bone removal CLASSIFICATION OF BONES ACCORDING TO DEVELOPMENT OSSIFICATION Formation of bone by osteoblasts INTRAMEMBRANOUS OSSIFICATION Formation of bone within connective tissue membranes Membranous bones – flatbones ENDOCHONDRAL OSSIFICATION Bone formation that occurs inside hyaline cartilage Hyaline cartilage- bone Long bones INTRAMEMBRANOUS OSSIFICATION ENDOCHONDRAL OSSIFICATION  BONE GROWTH APPOSITIONAL GROWTH Increase in width or diameter of the bone Osteoblasts deposit new bone matrix on the surface of bones between the periosteum and existing bone matrix BONE GROWTH GROWTH IN LENGTH Occurs in the epiphyseal plate Through endochondral ossification BONE REMODELLING Removal of existing bone by osteoclasts and the deposition of new bone by osteoblasts. Responsible for changes in bone shape, adjustment to stress, bone repair, calcium ion regulation  BONE IS THE MAJOR STORAGE SITE OF CALCIUM When BLOOD CALCIUM LEVEL is too high BONE AND Osteoclast activity decreases CALCIUM Osteoblasts remove calcium from blood to form new bone HOMEOSTASIS When BLOOD CALCIUM LEVEL is too low Osteoclast activity increases Osteoclasts release calcium from bones into the blood  PARATHYROID HORMONE released when blood calcium decreases increases blood calcium concentration increases bone resorption Stimulates formation of active vitamin D Stimulates the kidney to take up calcium from urine and return it to the blood HORMONAL CALCITONIN REGULATION released when blood calcium increases decreases blood calcium concentration inhibits bone resorption produced by thyroid gland VITAMIN D Increases blood calcium levels Released when blood calcium levels are too low  HORMONAL REGULATION ESTROGEN Increases the number of osteoblasts thereby stimulating bone formation ANDROGEN Delays closure of the epiphyseal plates GROWTH HORMONE Secreted by anterior pituitary gland Stimulates mitoses of the chondrocytes at the epiphyseal plate  DIVISIONS OF THE SKELETON AXIAL SKELETON. Forms the longitudinal axis of the body total of 80 bones 3 regions: SKULL, VERTEBRAL COLUMN, BONY THORAX APPENDICULAR SKELETON. Bones of the limbs and girdle  CLASSIFICATION F BONES COMPACT BONES Strong and dense Bulk of long bones Made up of osteon or Haversian system SPONGY BONES CANCELLOUS BONE contain irregular lattices of thin bone columns called trabeculae Support and protect the red bone marrow https://imagesvc.meredithcorp.io/v3/mm/image?url=https://i.pinimg.com/originals/32/64/3a/32643acd8ce62338cf3f81827bdaacb2.jpg SESAMOID BONE enclosed in tendon and fascial tissue adjacent to bone AXIAL SKELETON.  SKULL Formed by cranium and facial bones CRANIUM (8) Protects the brain Attaches brain and neck FACIAL BONES (14) Framework of the face Has openings for passage of air and food Anchor facial muscles of expression  CRANIUM 8 CRANIAL BONES 2 parietal 2 temporal 1 occipital 1 frontal Sphenoid ethmoid https://upload.wikimedia.org/wikipedia/commons/thumb/3/39/Cranial_bones_en_v2.svg/1200px- Cranial_bones_en_v2.svg.png  FRONTAL BONE Anterior portion of the cranium Articulates with the parietal bones through coronal suture  PARIETAL BONES Form the superior and lateral aspects of the skull  OCCIPITAL BONE Forms the posterior wall and base of the skull Foramen magnum Opening where the brain exits the skull to form the spinal cord  TEMPORAL BONES Inferolateral aspect of the skull and parts of the cranial floor Regions: Squamous Tympanic mastoid Petrous Contains the mastoid process and styloid process https://images.ctfassets.net/u2qv1tdtdbbu/7gq5qKCCczzmysskqKOCkE/02f93d0c7305ee8f177601bda f81bedd/ce591-fig05-temporal-parts.jpg  SUTURES special type of immovable joint that joins most of the skull bones. There are 4 major sutures in the skull CORONAL SUTURE unites the frontal bone and two parietal bones. SAGITTAL SUTURE attaches the two parietal bones. LAMBDOID SUTURE joins the parietal bones to the occipital bone. SQUAMOUS SUTURES seal the parietal bones to the temporal bones. https://img.grepmed.com/uploads/14114/anatomy-sutures-bones-skull-original.jpeg  SPHENOID BONE Butterfly-shaped bone in the middle cranial fossa forms the central wedge that connects with all other cranial bones Parts: Central body Greater wings Lesser wings Pterygoid processes https://teachmeanatomy.info/wp-content/uploads/Bony-Landmarks-of-the-Sphenoid- Wings-and-Pterygoid-Process-1024x413.jpg  ETHMOID BONE Small unpaired bone in the midline of the cranium Deepest of the skull bones Forms root of the nasal cavity between the 2 orbital cavities Located between nasal and sphenoid bones Composed of: Cribriform plate Perpendicular plate Ethmoidal labyrinth https://www.theskeletalsystem.net/wp-content/uploads/2022/04/Ethmoid-Bone-Labeled- Anatomy.jpg  FACIAL BONES 14 BONES All paired except: Mandible Vomer PAIRED BONES Maxillae Zygomatic Lacrimal Nasal Palatines Inferior conchae https://www.theskeletalsystem.net/wp-content/uploads/2022/03/Facial-Bones-Labeled.jpg AUDITORY OSSICLES NASAL Cavity NASAL SEPTUM Divides the nasal cavity into right and left halves Roof – cribriform plate of the ethmoid vomer bone + ethmoid bone Bone + Hyaline cartilage Bony shelves Nasal conchae https://cdn.britannica.com/78/74278-050-E4345BA2/Tissues-airway-soft-palate-sleep- apnea.jpg  PARANASAL SINUSES Air-filled spaces around the nasal cavity Functions: Lighten the skull Enhance the resonance of voice https://teachmeanatomy.info/wp-content/uploads/Anatomy-of-the-Paranasal-Sinuses.png VERTEBRAL COLUMN / SPINE Central axis of the skeleton Functions: Supports the weight of the head and trunk Protects the spinal cord Allows spinal nerves to exit the spinal cord Site for muscle attachment Permits movement of head and trunk INTERVERTEBRAL DISKS Fibrocartilage separating vertebral bodies  VERTEBRAL COLUMN Consists of 26 vertebrae Cervical vertebrae 7 Thoracic vertebrae 12 Lumbar vertebrae 5 Sacrum – shield shaped below lumbar vertebrae Fused S1-S5 Coccyx – triangular bone Tail bone 4 fused vertebrae https://cdn.britannica.com/57/54757-050-99173B1B/Human-vertebral-column.jpg  GENERAL STRUCTURE OF THE VERTEBRAE BODY OR CENTRUM Weight bearing Disc shaped VERTEBRAL ARCH Encloses the vertebral foramen VERTEBRAL FORAMEN Opening where the spinal cord passes through SPINOUS PROCESS Projects posteriorly from the vertebral arch TRANSVERSE PROCESS Lateral projections SUPERIOR AND INFERIOR ARTICULAR PROCESSES INTERVERTEBRAL FORAMEN Opening through which spinal nerve exits INTERVERTEBRAL DISCS https://upload.wikimedia.org/wikipedia/commons/thumb/7/7c/Vertebra_Superior_View- Cartilages that unite the bodies of adjacent vertebrae en.svg/1200px-Vertebra_Superior_View-en.svg.png CERVICAL VERTEBRA Small bodies Dislocations and fractures are more common here. Transverse FORAMEN – passage of vertebral arteries Bifid spinous process C1,2,7 atypical vertebrae C2-6 typical  C1 ATLAS No body and spinous process https://www.theskeletalsystem.net/wp-content/uploads/2022/12/Atlas-Bone-C1.jpg  C2 AXIS DENS OR ODONTOID PROCESS Projects superior to the body Forms pivot joint with the atlas https://wikimsk.org/w/img_auth.php/3/39/Atlantoaxial_joint.jpg  C7 VERTEBRA PROMINENS Long spinous process pointing downward which is not bifid https://prod-images- static.radiopaedia.org/images/53632374/Gray- square.001_gallery.jpeg THORACIC VERTEBRAE All articulate with ribs Heart-shaped bodies Long spinous process 2 facets and demifacets Circular vertebral foramen https://www.theskeletalsystem.net/wp- content/uploads/2022/05/Thoracic-Vertebrae-Anatomy- Labeled.jpg  LUMBAR VERTEBRAE Weight bearing Large kidney-shaped bodies Small triangular-shaped vertebral foramen Short, thick pedicles and laminae Flat hatchet-shaped spinous process https://ars.els-cdn.com/content/image/3-s2.0- B9780128128510000045-f04-01-9780128128510.jpg  THORACIC CAGE COMPONENTS Ribs Sternum Costal cartilages Thoracic vertebrae FUNCTIONS Protection (heart, lungs, great blood vessels) Supports shoulder girdle and upper limbs attachment for muscles Assists in breathing https://www.theskeletalsystem.net/wp- content/uploads/2023/01/Rib-Cage.jpg  STERNUM Breast bone Dagger-shaped Components: Manubrium (superior) Body Xiphoid process (inferior) https://bioluliaes.files.wordpress.com/2013/05/thoracic-cage-rib-cage-ribs-true-false- sternum.jpg?w=640  RIBS 12 pairs All attach to thoracic vertebrae posteriorly. Ribs 1-7 - true rib Vertebrosternal ribs Attached directly to sternum through the costal cartilages Ribs 8-10 false ribs Vertebrochondral ribs Attached indirectly to the sternum through the costal cartilage of the 7th rib Ribs 11-12 floating ribs Not attached to sternum https://samarpanphysioclinic.com/wp-content/uploads/2023/04/ribs-cageee.webp APPENDICULAR SKELETON Bones of the upper and lower extremities Pectoral girdle Pelvic girdle  PECTORAL GIRDLE Shoulder girdle Components Scapula – posterior Clavicle (collar bone) – anterior FUNCTIONS Attaches upper extremities to the axial skeleton Provide attachment points of muscles to move upper extremities https://www.theskeletalsystem.net/wp-content/uploads/2023/02/Pectoral-Shoulder- Girdle.jpg SHOULDER GIRDLE PECTORAL GIRDLE Glenoid fossa – attachment of head of humerus Acromion process – point of shoulder Clavicle- first bone to ossify; last to complete ossification  SCAPULA Shoulder blade Triangular flat bones Located between the 2nd to 7th ribs dorsally Connects the clavicle to the humerus https://cdn.britannica.com/06/99106-050-CE6AFD10/view-bones-shoulder-humerus-scapula-clavicle.jpg https://www.theskeletalsystem.net/wp-content/uploads/2021/09/Parts-of-Scapula-Labeled-Diagram.jpg  UPPER EXTREMITIES Upper limbs Consists of 37 bones per limb Components: Arm (brachium) Forearm (antebrachium) Hand (manus) https://www.researchgate.net/publication/340020607/figure/fig1/AS:870701124837377@1584602733888/A natomy-of-the-human-upper-limb-A-upper-limb-segments-and-B-shoulder-elbow-and.ppm  ARM HUMERUS Only bone of the arm Articulates with: Scapula - shoulder Radius and ulna – elbow part https://www.theskeletalsystem.net/wp-content/uploads/2021/08/Humerus.jpg  FOREARM BONES ULNA Medial position Slightly longer than radius Forms a major portion of the elbow joint with the humerus https://cdn.britannica.com/15/99115-050-2F721419/radius-ulna-supination.jpg FOREARM BONES OLECRANON PROCESS- point of the elbow ULNAR HEAD – prominent projection at the posterior ULNAR side of the wrist  FOREARM BONES RADIUS Lateral forearm bone Superior surface articulates with the capitulum of the humerus Head articulates with the radial notch of the ulna medially https://cdn.britannica.com/15/99115-050-2F721419/radius-ulna-supination.jpg https://prod-images-static.radiopaedia.org/images/19311369/adb4207d72c3daa13e0e4a3b7ddd77_gallery.jpeg  HAND COMPONENTS: Carpals – wrist bones Metacarpals – hand bones Phalanges – bones of the fingers https://anatomyinfo.com/wp-content/uploads/2018/06/hand-bones.png CARPAL BONES 8 bones She Looks Too Pretty PROXIMAL – lateral to medial Try To Catch Her scaphoid, lunate, triquetrum, pisiform Pisiform Sesamoid bone formed within the tendon of the flexor carpi ulnaris DISTAL – lateral to medial trapezium, trapezoid, capitate, hamate Hamate Projection on palmar surface – “hook of hamate” https://samarpanphysioclinic.com/wp-content/uploads/2023/02/Proximal- and-distal-rows-of-the-carpal-bones-e1677508240548-1200x720.webp  METACARPALS Bones of the palm 5 metacarpal bones Head articulates with the phalanges  PHALANGES Fingers / digits Long bones 14 phalanges per hand numbered 1 – 5 (thumb is number 1) Parts: Distal Middle Proximal Thumb – no middle phalanx  LOWER EXTREMITIES Pelvic girdle Thigh Leg foot https://www.researchgate.net/publication/355203662/figure/fig2/AS:1078816881541122 @1634221396660/Lower-extremity-anatomy-Bones-and-joints-24.jpg PELVIC GIRDLE PELVIS Pelvic girdle + coccyx  PELVIC GIRDLE Formed by a pair of hip bones/pelvic bones Ox coxae or coxal BONY PELVIS Coxal bones Sacrum Coccyx COXAL BONES Ilium Ischium pubis https://s3-us-west-2.amazonaws.com/courses-images/wp- content/uploads/sites/1512/2017/04/10231213/817_Ligaments_of_Pelvis.jpg  PELVIS Attaches the lower limbs to the axial skeleton transmits weight of the upper body to the lower limbs Supports the visceral organs of the pelvis  COXAL BONE ILIUM Large flaring bone at the superior region Articulates with the sacrum Consists of: body ala (wing-like portion) https://cdn.britannica.com/99/120999-050-8E7B574A/Bones- girdle.jpg?w=400&h=300&c=crop  COXAL BONE ISCHIUM Forms the posteroinferior part of the hip Articulates with ilium and pubis PUBIS Forms the anterior part of the hip https://cdn.britannica.com/99/120999-050-8E7B574A/Bones- girdle.jpg?w=400&h=300&c=crop  PELVIS MALE PELVIS FEMALE PELVIS Tilted less forward Tilted forward for childbearing Adapted for support of heavier True pelvis defines birth canal male built and stronger muscles Cavity of true pelvis: broad, Cavity of true pelvis: narrow and shallow with greater capacity deep  https://www.registerednursern.com/wp- content/uploads/2019/12/mfpelvis-social.png  LOWER LIMB COMPONENTS Thigh Leg Foot FUNCTION Carry the weight of the erect body https://upload.wikimedia.org/wikipedia/commons/thumb/7/7e/Human_l eg_bones_labeled.svg/640px-Human_leg_bones_labeled.svg.png  FEMUR Thigh bone Largest and strongest bone of the body Articulations: Proximal – hip Distal – tibia and fibula https://cdn.britannica.com/92/99192-050-52E7AB99/view- femur.jpg  LEG BONES TIBIA Shin bone Receives the weight of the body from the femur and transmits it to the foot Medial leg bone Forms the medial malleolus https://www.researchgate.net/publication/260302268/figure/fig1/AS:668935460503 580@1536498050889/Figure-Human-Tibia-and-Fibula-Source-Encyclopedia- Britannica-Inc-Figure-1-Human.png  LEG BONES TIBIA Shin bone Major weight bearing bone of the leg Medial leg bone Forms the medial malleolus https://www.researchgate.net/publication/260302268/figure/fig1/AS:668935460503 580@1536498050889/Figure-Human-Tibia-and-Fibula-Source-Encyclopedia- Britannica-Inc-Figure-1-Human.png  LEG BONES FIBULA Splint bone Stick-like bone Lateral leg bone Forms the lateral malleolus https://www.researchgate.net/publication/260302268/figure/fig1/AS:668935460503 580@1536498050889/Figure-Human-Tibia-and-Fibula-Source-Encyclopedia- Britannica-Inc-Figure-1-Human.png  TARSALS Ankle bones Composed of 7 bones Calcaneus (heel bone) Carries most of the weight together with the talus Points of attachment for Achilles (calcaneal) tendon Talus Articulates with tibia and fibula superiorly and calcaneus inferiorly https://www.theskeletalsystem.net/wp-content/uploads/2021/10/Tarsal- Bones.jpg  METATARSALS Consists of 5 (1-5) long bones (#1 hallux or big toe) Articulate with the phalanges Enlarged head of metatarsal 1 forms the ball of the foot https://www.theskeletalsystem.net/wp-content/uploads/2022/09/Metatarsal- Bones.jpg  PHALANGES Consists of 14 bones 3 phalanges per digit except hallux which has no middle phalanx https://www.physio- pedia.com/images/thumb/b/b0/Metatarsals.jpeg/250px- Metatarsals.jpeg IRREGULAR BONES TYPES OF JOINTS. FIBROUS JOINTS – joints that are connected by fibrous tissue Synarthroses : immovable joint Types: Sutures Gomphosis Connects teeth with bone cavity Syndesmosis Between radius and ulna Between tibia and fibula https://upload.wikimedia.org/wikipedia/commons/c/cc/904_Fibrou s_Joints.jpg CARTILAGINOUS JOINT Amphiarthroses – slightly movable joint symphisis pubis, intervertebral disk https://slideplayer.com/slide/10775915/38/images/6/Figure+8.2+Cartilaginous+joints..jpg SYNOVIAL JOINT Diarthroses – freely movable https://upload.wikimedia.org/wikipedia/commons/8/8b/907_Synovial_Joints.jpg  BALL AND HINGE JOINTS – SOCKET – movement in 1 movement in direction many directions knee and elbow shoulder and hip joints SYNOVIAL JOINTS PIVOT JOINTS – CONDYLOID allows rotation JOINTS – around the movement in 2 length of bone directions atlantoaxial joint wrist SYNOVIAL JOINTS SADDLE JOINT – like condyloid but with deeper articulating surface carpometacarpal joint of thumb GLIDING JOINT – bones slide over one another carpal and tarsal joints https://med.libretexts.org/@api/deki/files/44296/gaxs8uksrxw jnkmtslen.jpefixme?revision=1  REFERENCES HOEHNRIEB, E., & Hoehn, K. (2022). Human anatomy & physiology [Global edition]. Pearson. Seeley, R., VanPutte, C., Russo, A., & Regan, J. (2016). Seeley's anatomy & physiology. McGraw-Hill Education.  https://www.slideshare.net/arijabuhaniyeh/skeletal-system- 46731021 THANK YOU.