22_Axial Skeleton_Skull.pptx

Axial Skeleton Part 1 Chapter 6, Human Anatomy (LibreTexts) "Skeleton Sitting Smiling " by Clker-Free-Vector-Images is in the Public Domain, CC0 The Skeletal System • The adult skeleton has 206 bone • Subdivided into two major divisions • Axial Skeleton • 80 bones • Skull, vertebral column, thora...

Axial Skeleton Part 1 Chapter 6, Human Anatomy (LibreTexts) "Skeleton Sitting Smiling " by Clker-Free-Vector-Images is in the Public Domain, CC0 The Skeletal System • The adult skeleton has 206 bone • Subdivided into two major divisions • Axial Skeleton • 80 bones • Skull, vertebral column, thoracic cage • Appendicular Skeleton • 126 bones • Pectoral girdles, upper limbs, pelvis, lower limbs Axial and Appendicular Skeleton "Axial Skeleton" by OpenStax is licensed under CC BY 3.0 Skull • Supports the face and protects the brain • Divided into • Cranial bones: 8 bones that surround and enclose the brain • Facial bones: 14 bones that form the face Divisions of the Skull "Parts of the Skull" by OpenStax is licensed under CC BY 3.0 Cranial Bones and Sutures • Cranial Bones: • • • • • • Frontal bone Parietal bones (2) Temporal bones (2) Occipital bone Sphenoid bone Ethmoid bone • Sutures: fibrous band of tissue that connect bones of skull • • • • Coronal suture (between frontal and parietal bones) Sagittal suture (between parietal bones) Squamous suture (between parietal and temporal bones) Lambdoid suture (between parietal and occipital bones) Anterior View of Skull 1 "Skull" by OpenStax is licensed under CC BY 3.0 Lateral View of Skull "Lateral View of Skull" by Whitney Menefee is licensed under CC BY-NC 4.0 / A derivative from the original work Sutures of the Skull "Sutures of the Skull" by Whitney Menefee is licensed under CC BY 4.0 / A derivative from the original work and original work Frontal Bone • Orbital part: horizontal region making the superior side of orbits • Glabella: region between between eyebrows • Superciliary arch: region above eyebrows • Supraorbital margin: region where eyebrows are • Supraorbital foramen or notch: opening or depression on supraorbital margin • Zygomatic process: elevation for articulation with zygomatic bone Frontal Bone Image "Frontal bone close-up anterior" by Anatomography is licensed under CC BY-SA 2.0/Labels added by Chiara Mazzasette Parietal Bone Image "Parietal bone lateral" by Anatomography is licensed under CC BY-SA 2.0 Temporal Bones • Looks like a headset with a microphone • External acoustic meatus: lateral opening • Internal acoustic meatus: medial opening • Zygomatic process: elevation for articulation with zygomatic bone • Articular tubercle: elevation inferior to zygomatic process • Mandibular fossa: depression posterior to articular tubercle • Mastoid process: elevation inferior and posterior to external acoustic meatus • Styloid process: sharp elevation inferior to external acoustic meatus Temporal Bone "Temporal Bone" by OpenStax is licensed under CC BY 3.0 Occipital Bone • Has biggest opening • Foramen magnum: big opening through which brain stem goes through • Occipital condyle: articulating surface for first vertebra (atlas) • Hypoglossal canal: opening within occipital condyle, perpendicular to foramen magnum • External occipital crest: elevation extending from foramen magnum to external occipital protuberance • External occipital protuberance: elevation • Basilar part: anterior region for articulation with sphenoid bone Posterior View of Skull "Posterior View Skull" by OpenStax is licensed under CC BY 3.0 Sphenoid Bone • Looks like a butterfly or bat • Greater wings: wide elevations from the body • Lesser wings: narrow elevation from the body • Superior orbital fissure: opening between lesser and greater wings • Inferior orbital fissure: mainly visible from orbit, opening between greater wings and facial bones • Optic canal: opening for the optic nerve • Sella turcica: saddle-shaped depression between greater wings • Foramen rotundum: opening near anterior side of sella turcica • Foramen ovale: opening near posterior side of sella turcica • Foramen spinosum: opening posterior to foramen ovale Sphenoid Bone Image – Superior View "Sphenoid Bone" by Whitney Menefee is licensed under CC BY 4.0 / A derivative from the original work Sphenoid Bone Image – Posterior View "Sphenoid Bone" by Whitney Menefee is licensed under CC BY 4.0 / A derivative from the original work Ethmoid Bone • Looks like a flower with wilted leaves • Cribriform plate: superior region containing openings for olfactory axons • Crista galli: elevation of the cribriform plate • Perpendicular plate: medial elevation on the inferior side • Superior nasal concha: elevation towards midline • Middle nasal concha: elevation towards midline Ethmoid Bone Image "Ethmoid Bone" by OpenStax is licensed under CC BY 3.0 Superior View of Skull 1 "Superior-Inferior View of Skull" by Whitney Menefee is licensed under CC BY 4.0 / A derivative from the original work Additional Openings in-between Bones • Foramen lacerum: opening between sphenoid and temporal bones • Jugular foramen: opening between occipital and temporal bones • Carotid canal: opening of the temporal bone visible from an inferior view of the skull • Mnemonic image: The cowboy ROS sits on the saddle (sella turcica), holds the reins through the optical canal, puts his legs into the foramen lacerum and on the side of his horse his name (“ROS”) is labeled by: foramen Rotundum, foramen Ovale, foramen Spinosum.. Superior View of Skull 2 "Superior-Inferior View of Skull" by Whitney Menefee is licensed under CC BY 4.0 / A derivative from the original work Inferior View of Skull Base "Superior-Inferior View of Skull" by Whitney Menefee is licensed under CC BY 4.0 / A derivative from the original work Cranial Nerve Exits • Olfactory (CN I)  Cribriform plate • Optic (CN II)  Optic canal • Oculomotor (CN III)  Superior orbital fissure • Trochlear (CN IV)  Superior orbital fissure • Opthalmic (Trigeminal (CN V)  Superior orbital fissure • Abducens (CN VI)  Superior orbital fissure • Maxillary (Trigeminal (CN V)  Foramen rotundum • Mandibular (Trigeminal (CN V)  Foramen ovale • Facial (CN VII)  Internal acoustic meatus • Vestibulocochlear (CN VIII)  Internal acoustic meatus • Glossopharyngeal (CN IX)  Jugular foramen • Vagus (CN X)  Jugular foramen • Accessory (CN XI)  Jugular foramen • Hypoglossal (CN XII)  Hypoglossal canal Cranial Fossae • Regions formed by floor of cranial cavity • Anterior cranial fossa: houses frontal lobes • Middle cranial fossa: houses temporal lobes • Posterior cranial fossa: houses brainstem and cerebellum Facial Bones • Facial Bones: • • • • • • • • Zygomatic bones (2) Lacrimal bone (2) Nasal bones (2) Vomer Inferior nasal conchae (2) Palatine bones (2) Maxilla bones (2) Mandible Anterior View of Skull 2 "Skull" by OpenStax is licensed under CC BY 3.0 Sagittal Section of Skull "Sagittal Section of Skull" by OpenStax is licensed under CC BY 3.0 Zygomatic Bones • Looks like a sailing boat or a crescent moon • Temporal process: elevation for articulation with temporal bone • Frontal process: elevation for articulation with frontal bone • Maxillary process: elevation for articulation with maxilla bone • Zygomatic arch formed by zygomatic process of temporal bone and temporal process of zygomatic bone Zygomatic Bone Image "Left zygomatic bone close-up medial" by Anatomography is licensed under CC BY-SA 2.0 Vomer • Looks like a lightning bolt • Ala: elevation on the superior side • Vertical plate: medial region that forms part of the nasal septum Vomer Bone Image "Rotation Vomer bone" by Anatomography is licensed under CC BY-SA 2.0 Lacrimal Bone Image "Lacrimal bone - lateral view2" by Anatomography is licensed under CC BY-SA 2.0 Nasal Bone Image "Nasal bone anterior" by Anatomography is licensed under CC BY-SA 2.0 Inferior Nasal Concha Bone Image Photograph taken by Chiara Mazzasette Nasal, Lacrimal and Inferior Nasal Concha Comparison Photograph taken by Chiara Mazzasette Palatine Bones • Looks like a L • Perpendicular plate: lateral region (long leg of L) • Horizontal plate: inferior region (short leg of L); forms posterior region of hard palate Palatine Bone Image "Rotation palatine bone" by Anatomography is licensed under CC BY-SA 2.0 Maxilla Bones • Frontal process: elevation for articulation with frontal bone • Zygomatic process: elevation for articulation with zygomatic bone • Alveolar process: elevation that houses a tooth • Infraorbital foramen: opening inferior to the orbit • Orbital surface: region that makes part of the orbit • Anterior nasal spine: elevation at the midline Maxilla Bone Image "Maxilla" by OpenStax is licensed under CC BY 3.0 Mandible • Condylar process: superior elevation on the posterior region • Coronoid process: superior elevation on the anterior region • Mandibular notch: depression between condylar and coronoid process • Mandibular angle: region that makes the inferior angle of jawline • Mandibular ramus: region between the mandibular notch and angle • Alveolar process: elevation that houses a tooth • Mental foramen: opening inferior to teeth • Mental protuberance: elevation that makes the chin • Mandibular foramen: internal opening inferior to mandibular notch Mandible Bone Image "Mandible" by Whitney Menefee is licensed under CC BY 4.0 / A derivative from the original work Orbits • ”eye holes” • Made up of parts of 7 bones: • • • • • • • Frontal bone (superior) Zygomatic bone (lateral) Maxilla bone (inferior) Palatine bone (inferior) Lacrimal bone (medial) Ethmoid bone (medial) Sphenoid bone (posterior) Bones of the Orbit "Bones Forming Orbit" by OpenStax is licensed under CC BY 3.0 Nasal Cavity and Septum • Nasal cavity is made by: • • • • • Nasal bone (superior) Maxilla (lateral) Nasal conchae of ethmoid bone (lateral) Inferior nasal conchae (lateral_ Palatine bones (inferior) • Nasal septum is made by: • Perpendicular plate of ethmoid bone • Vertical plate of vomer Lateral Wall of Nasal Cavity "Nasal Cavity" by Whitney Menefee is licensed under CC BY 4.0 / A derivative from the original work Nasal Septum "Bone of Nasal Cavity" by OpenStax is licensed under CC BY 3.0 Paranasal Sinuses • Paranasal sinuses are found in the following bones: • • • • Frontal bone Sphenoid Ethmoid Maxilla Paranasal Sinuses Image "Paranasal Sinuses" by OpenStax is licensed under CC BY 3.0 Hyoid Bone • Looks like a vampire denture • Only bone in the body that does not articulate with any other bone. • Held in place by membranes that attach it to thyroid cartilage of larynx • Attachment site of many muscles • Used for swallowing and vocalizing Hyoid Bone Image "Hyoid Bone" by OpenStax is licensed under CC BY 3.0