LECTURE OUTLINE CHAPTER 7 Marieb The Skeletal system: Axial division Lecture Outline

I. AXIAL SKELETON

A. Structures 1. sutures a. coronal - between frontal and parietal b. lambdoidal - between occipital and parietal bones c. sagittal - between two parietal bones d. squamosal - between temporal and parietal bones

2. a. cranium - brain case 1) occipital - landmark - i. - articulate with atlas ii. occipital crest iii. external occipital protuberance - bump to lean your head against iv. nuchal lines - inferior and superior - muscle attachments v. jugular foramen vi. hypoglossal canals 2) parietal - landmark squamosal suture i. temporal lines - superior and inferior ii. parietal eminence 3) frontal - landmark - orbital area i. metopic suture -remnant of fusion between bones ii. frontal squama iii. suprorbital margins iv. / notch v. superciliary arch- behind eyebrows vi. lacrimal fossa vii. frontal crest viii. 4) temporal bones (2), landmark - external acoustic meatus i. squama ii. -reaches toward zygomatic iii. zygomatic arch iv. - articulation with mandible v. tympanic portion - contains ear vi. external auditory canal vii. mastoid process - hard lump behind ear viii. ix. styloid process - sharp pointy process x. xi. jugular foramen xii. xiii. foramen lacerum xiv. auditory tube xv. petrous portion - rock hard, inside xvi. internal acoustic canal - exit for nerve 5) sphenoid - i. -which contains the pituitary ii. hypophyseal fossa iii. anterior clinoid processes iv. v. vi. posterior clinoid processes vii. optic groove - optic nerves cross here viii.. - passage for optic nerve ix. x. xi. xii. xiii. greater wings xiv. sphenoidal spine xv. pterygoid process xvi. 6) ethmoid - landmark - i. - opening for olfactory nerve ii. crista galli - tiedown for meninges iii. lateral masses - bulk of bone iv. superior nasal conchae v. middle nasal conchae vi. ethmoidal sinuses - spaces in masses vii. perpendicular plate - meets vomer to form nasal septum b. facial bones 1) two nasal - form bridge of nose 2) two maxillae i. orbital rim ii. frontal process - reaches toward iii. alveolar process - sockets for teeth iv. inferior orbital fissure v. infraorbital foramen vi. maxillary sinus vii. palatal process - horizontal, roof of mouth viii. hard palate ix. incisivie foramen 3) mandible i. body ii. ramus iii. coronoid process - highest point iv. mental foramen v. mandibular notch vi. alveolar process - sockets for teeth vii. mylohyoid line - muscle attachment viii. mandibular foramen - inside ramus ix. mandibular canal 4) two zygomatics – cheek bones 5) two palatines 6) two lacrimals 7) vomer - inferior portion of nasal septum 8) two inferior conchae

c. hyoid – no articulations d. three pairs of auditory – malleus, incus & stapes e. sinuses – i. paranasal – all open into nasal cavity a) frontal b) ethmoid c) sphenoid d) maxillary ii. sealed a) mastoid sinus

B. Fetal skull - many bones separate for growth and birth 1. fontanels a. frontal ( anterior) - between 2 frontal s and 2 parietal b. posterior (occipital) - between occipital and parietals c. pair anteriolateral (sphenoid) - between parietals, sphenoid, and temporals d. pair posteriolateral (mastoid) - between temporal, occipital, and parietals

C.. Spinal column 1. regions a. cervical 1-7 have transverse foramina C1 – atlas, no centrum, articulates w/ superiorly and axis inferiorly. C2- axis – has a superior process, the dens, around which the atlas articulates in a side-to side motion. C7 - has long straight spinous process (vertebral prominens) b. thoracic – 1-12, ribs attached, will have costal facets for ribs c.. lumbar – 1-5 large, blocky spinous processes d. sacrum 1-5 fused into one block e. coccyx – 1-3/5 sections, partially fused

2. curvatures - normal a.. primary – the direction of a fetal spinal curvature, concave anteriorly 1). thoracic 2). sacral b. secondary – convex anteriorly, develop later in development, 1). cervical - develops when able to hold head up 2). lumbar - develops when able to stand 3 curvatures – abnormal a. scoliosis – lateral curvature mainly in thoracic region b. kyphosis – exaggerated thoracic curvature, “hunchback”, „dowager‟s hump” c. lordosis – exaggerated lumbar curvature, “swayback” 4.. vertebrae features a. body , centrum b. neural arch made up of lamina and pedicles c. neural foramen/ vertebral foramen – surrounded by centrum and neural arch. d. processes i. spinous – unpaired ii. transverse – paired iii. superior articulating – paired iv. inferior articulating - paired D. Ribs and Sternum 1. 12 pairs of ribs a. 7 pairs true- each attach to sternum by cartilage b. 5 pairs false i. 3 just false - attach indirectly to sternum ii. 2 pair floating - no sternal attachment 2. sternum a. manubrium b. body c. xiphoid