ANP1111 Lecture 7 2024 Bones & Joints Part 2 PDF

https://www.dreamstime.com/illustration/skeleton-waving.html  VERTEBRAL COLUMN 33 bones of which 24 remain separate (flexibility) and the remaining 9 fuse to form 2 composite bones (sacrum & coccyx); ~70 cm long in adult of average height 7 cervical, 12 thoracic, 5 lumbar, 5...

https://www.dreamstime.com/illustration/skeleton-waving.html  VERTEBRAL COLUMN 33 bones of which 24 remain separate (flexibility) and the remaining 9 fuse to form 2 composite bones (sacrum & coccyx); ~70 cm long in adult of average height 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 3/4 coccygeal Fig. 7.16 3 main functions: (1) weight-bearing (2) anchor for muscles & ligaments (3) protection of spinal cord NORMAL CURVATURES resilience & flexibility cervical & lumbar: concave thoracic & sacral: convex Fig. 7-18 ABNORMAL SPINAL CURVATURES SUPPORTING ELEMENTS OF VERTEBRAL COLUMN 1. Ligaments: strap-like; support column of bones so stay upright major supporting ligaments are anterior & posterior longitudinal ligaments continuous bands down front & back of vertebral bodies from neck to sacrum broad anterior is strongly attached to bony vertebrae & the discs; prevents hyperextension of spine posterior is narrow, weaker & attached only to the discs; prevents hyperflexion of spine Fig.7.17b 2. Intervertebral Discs: cushioning between bony vertebral bodies - shock absorbers - 25% length of vertebral column each is circular with nucleus pulposus in centre & annulus fibrosus around periphery nucleus pulposus is like a rubber ball »» elasticity & compressibility annulus fibrosus holds together successive vertebrae & resists tension in spine discs thickest in lumbar/cervical regions » flexibility Fig. 7.17 MRI showing herniated disc  A TYPICAL VERTEBRA: get larger as one descends the column Fig. 7.19 weight-bearing body + vertebral arch vertebral arch = 2 pedicles + 2 laminae arch + body enclose a vertebral foramen (What forms the vertebral canal? What passes through here? ) pedicles have notches on superior & inferior surfaces → intervertebral foramina (what passes through these?) 7 processes from each vertebral arch: 1 spinous process → muscle attachment 2 transverse processes - 1 per side for muscle attachment paired superior & inferior articular processes - link vertebrae above & below; smooth, collagen-coated facets for articulation  CERVICAL VERTEBRAE 7 total; #1 & 2 have unusual structures & no intervertebral disc #3-7 are considered typical: (1) body oval, broader side-to-side than front-to-back (2) spinous process short & split at end (except #7 - sticks out – can be palpated/not split) (3) vertebral foramen is a large (4) each transverse process contains a transverse foramen for passage of the vertebral artery to the brain Typical Cervical Vertebrae (C3-C7): Table 7.2a Fun Fact from Visible Body Fig. 7.20 Atlas, Greek god tasked by Zeus to eternally hold up the heavens Atlas: (Cervical Vertebra #1) no body & no spinous process posterior & anterior neural arches lateral masses with superior & inferior articular facets articulation of superior articular facets with occipital condyles allows “yes” Axis: more like C3-C7, except for dens or odontoid process = pivot [allows ?] dens is “missing” body from atlas Atlas: facet for dens THORACIC VERTEBRAE 12 in all; all have ribs attached; increase in size from first to last (1) body roughly heart-shaped & bears facets for ribs (paired demi-facets) (2) vertebral foramen is circular (3) spinous process long, points  (4) transverse processes have facets for articulation with tubercles of ribs Table 7.2 b LUMBAR VERTEBRAE lower back » major weight-bearing function bodies are kidney-shaped & increase in size from top to bottom (1) pedicles & laminae shorter & thicker than those of other vertebrae (2) spinous processes are flat & short - project directly back (3) vertebral foramen is triangular (4) orientation of inferior & superior facets unique - curved; sup faces in & inf faces out Table 7.2 c  anterior view Fig. 7.22 SACRAL posterior view VERTEBRAE starts as 5 separate vertebrae »» fuse in adolescents = sacrum articulates with 5th lumbar & laterally with hip bones (sacroiliac joint) note: sacral promontory, transverse lines & sacral foramina note: median sacral crest, sacral canal, sacral hiatus COCCYGEAL VERTEBRAE tailbone = 3 or 4 fused coccygeal vertebrae attachment area for some pelvic ligaments, but otherwise quite useless  BONY THORAX thoracic vertebrae + ribs + costal cartilages + sternum protective cage around heart, lungs & major blood vessels supports shoulder girdle & upper limbs provides area of muscle attachment for back, chest & shoulders STERNUM anterior midline of thorax fusion of 3 bones: manubrium, body, xiphoid process manubrium articulates with clavicles via clavicular notches; also with 1st pair of ribs body has notches for articulation with 2nd to 7th ribs attachment of some abdominal muscles to xiphoid process Fig. 7.23 3 important anatomical landmarks: (1) Jugular notch: indentation you can palpate (2) Sternal angle: cartilaginous hinge between manubrium & body of sternum (3) Xiphisternal joint: fusion of sternal body & xiphoid process RIBS 12/side; all attach at back to vertebral column curve inferiorly & anteriorly 7 true ribs attach to sternum directly; remaining 5 are false ribs » ribs 8-10 attach to sternum indirectly via costal cartilages & rib 7 » ribs 11 & 12 are not attached anteriorly = floating ribs RIBS (cont.) typical rib is a bowed, flat 3 bone shaft, head, neck, tubercle 4 main portion is shaft – what is the costal groove? 4 note head with 2 facets - one articulates with the demi-facet on the body of the same-numbered thoracic vertebra, other with that on the body of superior vertebra tubercle articulates with transverse process of same-numbered thoracic 4 vertebra Fig. 7.24 a & b  APPENDICULAR SKELETON Fig. 7.25 pectoral girdle; pelvic girdle plus upper & lower limbs PECTORAL GIRDLE 2 pairs of bones: clavicles & scapulae - almost a complete circle around upper trunk to make shoulders: glenoid cavity » anteriorly: ……………………………….. » laterally: ………………………………… » posteriorly: …………………………… bones are light & very movable - attachment points of muscles to move upper limbs Clavicles: (= collarbones) (1) scapulae attached to other bones only mildly S-shaped laterally insertion points for muscles, also (2) socket of shoulder joint (glenoid a brace to push arms laterally cavity) is shallow & poorly reinforced curvature ensures outward fracture, away from subclavian artery  Fig. 7.27a right scapula; anterior view Scapulae (= shoulder blades) thin, triangular, flat bones dorsally, between ribs 2 & 7 note superior, medial & lateral borders note spine acromion (articulates with acromial end of clavicle), coracoid process (biceps muscle) UPPER LIMB 30 separate bones: arm, forearm, wrist, and hand Table 7.3 Humerus: longest bone of upper limb and the only bone of the “arm” articulates with scapula proximally & radius + ulna distally NOTE: head (inserts into glenoid cavity - in what way?), anatomical neck, greater tubercle, lesser tubercle (what attach here?), intertubercular sulcus, surgical neck (what happens here?), deltoid tuberosity Fig. 7.28: right humerus (anterior and posterior) 2 condyles & 2 epicondyles: trochlea: articulates with ulna capitulum: articulates with radius ulnar nerve runs behind the medial epicondyle  O Forearm: 2 parallel long bones: radius & ulna articulates with humerus & wrist bones; also articulate with each other at proximal & distal radio-ulnar joints what is the interosseous membrane? Ulna: (elbow joint!) slightly longer than radius olecranon & coronoid process locking of olecranon prevents elbow hyperextension radial notch on coronoid process styloid process has ligament to wrist Fig. 7.29: Right forearm Radius: (wrist joint!) head at proximal end; distal end is the wider end distal end has medial ulnar notch & lateral styloid process  Fig. 7.28 d & e: Articulation at the elbow Fig. 7.29e  Anterior view of right hand Fig. 7.30 HAND 27 bones in total includes bones of carpus, metacarpus & phalanges Carpus (wrist) 8 carpels only scaphoid & lunate articulate with radius “So Long To Pittsburgh” (scaphoid, lunate, triquetrum, pisiform) “Time To Call Home” (trapezium, trapezoid, capitate, hamate) “Sally Left The Party To Take Cathy Home”  thumb = pollex IV III II V I Metacarpus: 5 long bones - distal ends are knuckles numbered 1-5 from thumb to little finger proximal ends are articulated with wrist bones Phalanges (phalanx in the singular): 3/finger & 2/thumb = miniature long bones numbered 1-5 from thumb to little finger proximal, middle & distal except for thumb which has only proximal & distal PELVIC GIRDLE attaches lower limbs, transmits weight of upper body to lower limbs, supports visceral organs of pelvis forms a complete circle left & right hip bones (coxal bones) unite anteriorly & with sacrum at back each os coxa consists of 3 bones that fuse at puberty: ilium, ischium, pubis acetabulum is area where all 3 bones join »» forms socket of hip joint Fig. 7.31 Ilium: large flaring bone that forms most of os coxa note iliac crest (superior border); iliac spines (attachment of muscles) pelvic brim is superior margin of true pelvis anteriorly, the body of the ilium joins the ischium and the pubis Ischium: postero-inferior part of hip bone superior body joining ilium and thinner, inferior ramus What is the ischial tuberosity? Pubis: anterior part of ox cosa 2 pubic bones unite at pubis symphysis note pubic crest, obturator foramen (blood vessels & nerves) Fig. 7.32a: Lateral view of right hip bone  LOWER LIMB: thigh, leg & foot Thigh: femur = largest, longest & strongest bone Note: head, fovia capitis (ligament to acetabulum) neck (angles laterally to shaft; weak →??) linea aspera, lat & med condyles (articulate with tibia), Where are the lat & med epicondyles (muscles), greater and lesser patellar surface (between condyles) trochanters? Patella Fig. 7.34: Right femur Anterior Posterior Leg: 2 parallel bones: tibia & fibula interosseus membrane + proximal & distal tibiofibular joints (rigid) the fibula is not a contributor to the knee joint Tibia: transfers weight from femur to foot; next largest & strongest bone NB: med & lat condyles, anterior border, tibial tuberosity (patellar ligament) Fibula: note head & lateral malleolus Fig. 7.35 Foot: total of 26 bones: tarsus (ankle bone), metatarsus & phalanges Tarsus: 7 tarsal bones: largest is the calcaneus (heel bone) and second largest is the talus (part of ankle joint) Fig. 7.36 Metatarsus: 5 miniature long bones numbered 1-5 (medial great toe = +1) Phalanges: big toe (hallux) has two & remaining toes have 3 each - proximal, middle & distal Which phalanx is the big toe missing?? Fig. 7.36a