Skull - Skull Sutures • Immovable joints • Form...

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Unformatted text preview: Skull Sutures • Immovable joints • Form boundaries between skull bones • Five sutures – Coronal – Sagittal – Lambdoid – Squamous – Frontonasal Contains several cavities • Cranial cavity • Orbit • Nasal cavity • Buccal cavity • Paranasal sinuses • Inner­ear cavities Cranial Cavity • Anterior cranial fossa • Middle cranial fossa • Fosterior cranial fossa Paranasal Sinuses Cranial Bones • • • • • • 1frontal 2 parietal 2 temporal 1 occipital 1 sphenoid 1 ethmoid Frontal Bone • Extends from the supra orbital margin to the coronal suture Frontal Bone Gabella­ smooth area of the frontal bone Margin is perforated by the supraorbital foramen or (supraorbital notch) Parietal Bone • Bordered by 4 sutures Parietal Bone – Sagittal – Coronal – Lambdoid – squamous • Temporal Lines – superior and inferior • attachment for the temporalis muscle, a chewing muscle that passes between the zygomatic arch and temporal bone and inserts on the mandible temporal lines Sagittal suture Lambdoid suture Superior suture line Inferior suture line Thickenings that form an arch across the parietal and frontal bones. • Superior and inferior suture lilnes mark the attachment of the large fan shaped temporalis muscles (chewing muscle) Occipital Bone Temporal Bone Four Parts of the Temporal Bone 1. Squamous part­ has two prominent features – Zygomatic process­ which forms part of the zygomatic arc (cheekbone) – Mandibular fossa • Mandibular (glenoid) fossa­ a depression where the mandible articulates with the cranium Mandibular or Glenoid Fossa Mastoid process Four Parts of theTemporal Bone 2. Tympanic part­ a small ring of bone that borders the external acoustic meatus – Styloid process­ a pointed spine on its inferior surface • Provides attachment for muscles of the tongue, pharynx, and hyoid bone Four Parts of theTemporal Bone 3. Mastoid part – Mastoid process­ prominent lump behind the earlobe • • Filled with ear sinuses that communicate with the middle­ ear cavity Can become infected (mastoiditis) and possible spread to the brain Four Parts of theTemporal Bone 4. Petrous part­ resembles a little mountain range separating the middle cranial fossa from the posterior fossa – Houses the middle and inner ear cavities – Internal acoustic meatus­ allows passage of the vestibulocochlear verve (hearing and balance) – Carotid canal­ passes the internal carotid artery – Jugular foramen­ fromed by the temporal bone and the occipital bone and passes the internal jugular vein Carotid Canal Jugular Foramen Mastoid air cells Hypoglossal canal Foramen magnum Occipital Bone • Basilar part – foramen magnum – occipital condyle – hypoglossal canal – Venous sinus grooves – external occipital protuberance­ attaches the nuchal ligament that binds the skull to the vertebral column – Superior nuchal line­ identifies the superior part of the neck and provides attachment to the skull for several neck and back muscles. – Inferior nuchal line­ provides attachment for the deep neck muscles Venous sinus grooves Sphenoid Bone Sphenoid Bone • Lesser wing – forms the posterior wall of the orbit – contains the optic foramen (optic nerve and ophthalmic artery) – anterior clinoid process­ guard the optic foramen – superior orbital fissure­ nerves for muscles of eye movement • Body – sella turcica • has deep pit that called the hypophyseal fossa which houses the pituitary gland • turberculum sellae­ anterior raised margin • dorsum sellae­ posterior margin • covered by fibrous membrane and has a stalk that penetrates the membrane and that connects the pituitary to the hypothalamus Sella turcica Sphenoid Bone • Greater wing – foramen rotundum­ branch of trigeminal – foramen ovale­ branch of trigeminal – foramen spinosum­ artery to the meninges – foramen lacerum­ filled with cartilage, no vessels are nerves transmitted – Pterygoid plates (medial and lateral)­ provide attachment for jaw muscles • Sphenoid sinuses anterior clinoid process optic foramen turberculum sellae foramen rotundum foramen ovale foramen spinosum sella turcica dorsum sellae Ethmoid Bone Ethmoid Bone Ethmoid Bone • located between the orbital cavities and forms the roof of the nasal cavity • perpendicular plate­ inferior projection that divides the nasal cavity into right and left nasal fossae • nasal conchae (turbinate bones)­ superior and middle project into the nasal cavity – are covered with the mucous membrane – superior conchae contain receptors for the sense of smell Ethmoid Bone • Inferior nasal conchae is a separate bone extending into the nasal cavity Ethmoid Bone • Crista galli­ midsaggital crest that serves as an attachment for meninges • Cribriform plate­ horizontal shelf with numerous perforations that allow nerve fibers for smell to pass from the nasal cavity to the brain Facial Bones • bones that have no direct contact with the brain or meminges • total of 14 bones – 2 maxillae – 2 palatine bones – 2 zygomatic bones – 2 lacrimal bones – 2 nasal bones – 2 inferior nasal conchae – 1 vomer – 1 mandible Maxillae • Upper jaw • alveolar process­ points of maxillary bone that project between spaces of the teeth • alveolus­ teeth sockets • infraorbital foramen­ receives sensations from the nasal and and cheek that emerges through the foramen rotundum into the cranial cavity Maxillae • forms part of the orbit where it exhibits a gash called the inferior orbital fissure – provides passage for blood vessels and nerves of eye muscles •palatine process­ forms the anterior roof of mouth (hard palate) and floor of nasal cavity Palatine Bones • forms the posterior hard palate, part of the floor of the orbit, and part of the wall of the nasal cavity Palatine Bone Forms part of the floor of the orbit and hard palate Zygomatic Bone • forms the angle of the cheeks • frontal process­ part of the lateral wall of the orbit • zygomaticofacial foramen • Temporal process Lacrimal Bone • part of the medial wall of the orbit • lacrimal fossa­ houses the lacrimal sac – tears from the membranous sac drain into the nasal cavity Vomer • forms the anterior half of the nasal septum Nasal Septum • Consist of – perpendicular plate of the ethmoid bone – Vomer – Septal cartilage Mandible • strongest bone of the skull and the only one that can move • supports teeth and provides attachment for the muscles of mastication and facial expression • mental foramen­ passage of blood vessels and nerves of the chin • mandibular foramen­ nerve and blood vessel that supplies the lower teeth • condyloid process • mandibular condyle • coronoid process • temporomandibular joint (TMJ) 1. Ramus of the mandible 2. Mandibular angle 3. Body of the mandible 1. Mandibular notch 2. Mandibular condyle 3. Mandibular foramen 4. Coronoid process 5. Alveolar margin 6. Mental foramen Auditory Ossicles Hyoid Bone • does not articulate with any other bone • suspended from the styloid process of the skull by the small stylohyoid muscle and stylohyoid ligament • serves as attachment of several muscles that control the mandible, tongue, and larynx • fractured hyoid bone can be used as evidence of strangulation 1. Greater horns 2. Lesser horns 3. Body Anterior Cranial Fossa Frontal Lobe Middle Cranial Fossa Temporal Lobe Posterior Cranial Fossa Cerebellum posterior anterior Cat humerus, radius and ulna 1. head 2. lesser tuberosity 3. greater tuberosity 4. bicipital groove 5. deltoid tuberosity 6. supracondyloid foramen 7. medial epicondyle 8. lateral epicondyle 9. supracondyloid ridge 10. olecranon fossa 11. capitulum 12. trochlea 13. coronoid fossa 14. radial fossa 15. shaft 16. neck 17. bicipital tuberosity 18. styloid process 19. ulnar notch 20. olecranon 21. semilunar notch 22. coronoid process 23. radial notch Cat humerus, radius and ulna 1. head 2. lesser tuberosity 3. greater tuberosity 4. bicipital groove 5. deltoid tuberosity 6. supracondyloid foramen 7. medial epicondyle 8. lateral epicondyle 9. supracondyloid ridge 10. olecranon fossa 11. capitulum 12. trochlea 13. coronoid fossa 14. radial fossa 15. shaft 16. neck 17. bicipital tuberosity 18. styloid process 19. ulnar notch 20. olecranon 21. semilunar notch 22. coronoid process 23. radial notch ...
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This note was uploaded on 12/08/2011 for the course AMY 2A taught by Professor Jamesivey during the Spring '06 term at Riverside Community College.

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