ANP1111 Lecture 6 2022 Bones & Joints Part 1 PDF

 THE SKELETON (Chapter 7) 206 bones in human skeleton - make up about 20% of body weight grouped into axial and appendicular skeletons axial skeleton = bones of skull, vertebral column, rib cage appendicular skeleton = bones of upper & lower limbs + pectoral/pelvic...

 THE SKELETON (Chapter 7) 206 bones in human skeleton - make up about 20% of body weight grouped into axial and appendicular skeletons axial skeleton = bones of skull, vertebral column, rib cage appendicular skeleton = bones of upper & lower limbs + pectoral/pelvic girdles (attach limbs to axial skeleton) AXIAL SKELETON 80 bones SKULL most complex 2 sets of bones: cranial + facial = 22 bones most skull bones are flat bones; (except mandible);united by sutures facial bones form anterior part of skull & cranial bones form the rest skull has eye orbits & paranasal sinuses, houses organs of hearing, has 85 openings for nerves, blood vessels & spinal cord Fig 7.1 A) Cranium: cranium can be divided into a vault & a base vault: forms superior, lateral & posterior aspects of the skull + forehead base: inferior aspect of skull cranium surrounds & protects brain & organs of hearing & balance internally, 3 bony ridges divide the cranial base into 3 distinct areas: anterior (highest) fossa, middle fossa & posterior (lowest) fossa B) Facial bones or Face: form framework of the face contain the cavities for the sensory organs of sight, smell & taste provide openings for passage of air & food secure the teeth anchor the facial muscles that we use to show our feelings Fig. 7.4a Cranium: 8 cranial bones are the paired parietal & temporal bones & the unpaired frontal, occipital, sphenoid & ethmoid bones curvature allows them to be self-bracing; can be strong while being quite thin Fig. 7.5a  Fig. 7.4a Fig. 7.2 (i) Frontal Bone: dome-shaped bone; also forms the roof of the orbits & contributes to the anterior cranial fossa articulates with paired parietal bones posteriorly note supraorbital margin, supraorbital foramen, and glabella area lateral to glabella has left & right frontal sinus  (ii) Parietal Bones paired - form superior & lateral aspects of skull therefore form bulk of cranial vault Fig. 7.4b Fig. 7.5a (iii) Occipital Bone: single bone at base of skull; helps form post aspect of skull also forms walls of the posterior cranial fossa attaches anteriorly to the 2 parietals & 2 temporals & attaches to sphenoid  Fig. 7.6a (iii) Occipital Bone (cont.) large hole at base = foramen magnum (passage for ………...…….) occipital condyles on each side of foramen magnum = site of articulation with first cervical vertebra external occipital protuberance = projection at back of skull - more prominent in males (iv) Temporal Bones paired; form inferior & lateral aspects of skull and parts of the cranial floor located just below the 2 parietal bones; have 3 very different areas or regions Fig. 7.5c 1) Squamous part: flattened forms zygomatic process to cheekbone (zygomatic bone) mandibular fossa receives condyle of mandible 2) Tympanic part: surrounds external acoustic meatus 3) Petrous part is on the internal aspect of the temporal bone contributes to cranial base; houses middle and inner ear cavities mastoid process is attachment Fig. 7.8: Temporal Bone site for some neck muscles styloid process is attachment area for muscles of the tongue & some neck muscles several important foramina associated with this part of the temporal bone: jugular foramen, carotid canal, internal acoustic meatus (v) Sphenoid Bone: complex bone; difficult to visualize; articulates with all other cranial bones forms base of middle cranial fossa; contributes to base of anterior cranial fossa Fig 7.7a: Superior view of floor of cranial cavity  Fig. 7.9 central body which contains sphenoid sinuses 3 projections: greater & lesser wings (orbits, MCF & ACF) pterygoid processes (muscles for ?) optic foramina (canals): for optic nerves superior orbital fissure between greater & lesser wings (cranial nerves for eye movement) Cranial cavity floor showing major fossae www.upstate.edu/cdb/ grossanat/imgs/sklatsb1.jpg From Visible Body: Go into the Library online and search Collections (choose Omni) Enter Visible Body in the box and click Search It will come up as a Data Base right at the top Click on it and then Choose Visible Body: Anatomy & Physiology You may then need to login but then you can launch the software and explore! (vi) Ethmoid bone: approximates a cube that lies deep between the orbits & the nasal cavities cribriform plate forms roof of nasal cavity & floor of anterior cranial fossa; tiny holes (olfactory foramina) transmit olfactory nerves perpendicular plate projects inferiorly to contribute to nasal septum crista galli projects superiorly to attach to dura mater of brain Fig. 7.10 lateral masses contain ethmoid sinuses medially are superior & middle nasal conchae laterally are orbital plates - contribute to medial walls of orbits From Visible Body: Major Cranial Sutures: bones of the adult skull are firmly united by sutures 4 main sutures that connect the cranial bones (1) Coronal suture: frontal bone & 2 parietal bones (2) Squamous suture: parietal bone & temporal bone (3) Lambdoid suture: occipital bone & 2 parietal bones Fig. 7.5c: Midsagittal view of skull (4) Sagittal suture: 2 parietal bones Sutural bones: tiny irregular bones; can occur within cranial suture additional ossification centres that appeared rapidly during fetal development Fig. 7.4b Facial Bones: 14 bones of which mandible & vomer are unpaired paired bones are: maxillae, zygomatic, nasal, lacrimal, palatine & inferior conchae (i) Mandible: lower jawbone - strongest & largest bone of the face body is the horizontal part & contains the chin; the left & right rami join body at the mandibular angle note: mandibular notch, coronoid process (insertion of temporalis muscle), mandibular condyle, alveolar margin (contains tooth sockets), mandibular foramina (nerves to teeth in lower jaw) & mental foramina (blood vessels & nerves to chin & lower lip) Fig. 7.11a  Fig. 7.11b (ii) Maxillary bones: fused medially alveolar margins hold teeth of upper jaw palatine processes project posteriorly forming anterior 2/3 of hard palate note: (incisive fossa) (passage of blood vessels & nerves), frontal processes & zygomatic processes main portion of bone on each side has maxillary sinus - these are the sinuses that often get infected http://www.pathologyoutlines.com/topic/mandiblemaxillanasopalatine.html (iii) Zygomatic bones: = cheekbones articulate with zygomatic processes of maxilla, frontal & temporal bones also contribute to inferolateral margins of the orbit (iv) Nasal bones: 2 tiny, rectangular bones that fuse medially to form bridge of nose articulate with frontal bone superiorly & maxillary bones laterally (v) Lacrimal bones: 2 fingernail-shaped bones in anterior, medial portion of orbit – articulate with: frontal bone ethmoid bone maxillae each has a depression (lacrimal fossa) for lacrimal sac  Orbits: zygomatic Fig. 7.13 frontal maxilla ethmoid lacrimal sphenoid palatine (orbital process)  (vi) Palatine bones: 2 L-shaped bones horizontal plates form part of hard palate vertical plates - nasal cavity & orbit (vii) Vomer: single thin bone forms nasal septum (see Fig. 7.4a) From Fig. 7.8 (viii) Inferior nasal conchae: [Remember: the superior and middle nasal conchae are part of the ethmoid bone] thin, curved bones - project medially largest of 3 pairs of conchae Fig.7.6a Fig. 7.14a: Bones forming the left lateral wall of the nasal cavity:  Fig. 7.14b: Contributions of ethmoid & vomer bones & cartilage to nasal septum: Fig. 7.15 Fig. 7.12 F E S M Paranasal Sinuses: frontal Hyoid: maxillary only bone of the body that does not sphenoid articulate with any other bone ethmoid supports tongue & gives attachment mucosa-lined, air-filled to muscles for swallowing & speech lighten skull and enhance horseshoe-shaped with a body + 2 resonance of voice; connect to pairs of horns nasal cavity so also help to warm & humidify incoming air This is a pretty good site for some basic practice of the easy stuff: https://ltsa.sheridancollege.ca/apps/human-anatomy/quiz_labeling_skull.html?bgImage=