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HUMAN ANATOMY AND PHYSIOLOGY The Skeletal System Notes 2 divisions: 1. ____________________________bones that form longitudinal axis 2. _______________________________bones of the limbs and girdles The system includes joints ,cartilage and ligaments. I. Bones:An Overview A. Functions-besides giving body shape and Form: 1. Support-supports body and cradles soft organs 2. Protection-protect soft organs-eg. Protects brain/vertebraespine and ribs for organs of the thoracic cavity 3. Movement-Skeletal muscles attach to bones by _______________and bones work as levers. 4. Storage ______in internal (marrow) cavities of bones Storehouse for minerals-esp.Ca and P….A small amount of Ca must be in blood at all times to reach the nerve tissue for transmission ,so muscles contract and help clot blood.Ca in bones as salts provide Ca 2+ ions for blood Hormones control the movement of Ca to and from blood according to body need…..too much Ca can be a problem 5. Blood Cell Formation or ________________________ in the marrow cavities of certain bones B. Classification of Bones (adult has 206 bones) » There are 2 main types of osseous tissue 1. ____________________________dense and looks smooth and homogeneous 2. ___________________________ made of needlelike pieces of bone and lots of open space 1 » Many sizes and shapes:-eg. Tiny pisiform bone of __________________-size of a pea and at the other extreme-the ________________-thigh bone is ~ 2’ long and has large ,ball shaped head » Shape grouping: 1. _____________________-longer than they are wide;shaft with heads at both ends ;mostly compact bone; bones of limbs (except patella ,wrist and ankle) 2. _________________________-generally cube shaped and mostly spongy bone ;bones of wrist and ankle;____________________bones-within tendonsspecial type of short bone-patella 3. ____________________-thin, flattened and usually curved-2 thin layers of compact bone sandwiching spongy bone-skull,ribs,sternum 4. __________________________don’t fit other categoriesvertebrae and hip Classification of Bones on the Basis of Shape Figure 5.1 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings 2 C. Structure of a long bone GROSS ANATOMY __________________-shaft-makes most of bone length and is __________________bone Diaphysis is covered by fibrous connective tissue membrane_________________________-Hundreds of connective tissue fibers,called perforating or Sharpey’s fibers secure periosteum to underlying bone _______________________at the ends of each long bone…consists of thin compact layer of bone filled with spongy bone…._________________cartilage covers the external surface (glassy hyaline cartilage gives smooth surface to decrease friction at joint surfaces ) Adult bones have a thin line of bony tissue at epiphysis-called ____________________________________-a remnant of epiphyseal( plate of hyaline cartilage in young ,growing bones) epiphyseal plates cause lengthwise growth of long bones At end of puberty,hormones inhibit long bone growth and the epiphyseal plate is completetly replaced w/bone • Cavity of shaft stores adipose tissue--_____________________________,or medullary cavity …In infants this area forms RBC’s-red marrow is there For adults ,red marrow confined in cavities of spongy bone of flat bones and epiphyses of some long bones —Note:Areas of red marrow are more limited in adults—to places such as sternum Surfaces have bumps holes and ridges=__________________________-show where muscles,tendons,and ligaments were attached and where blood vessels and nerves pass 1. projections or processes -grow out from bone surface---goes w/terms beginning w/T 2. depressions or ________________________-indentations in bone---goes w/terms starting w/F(except facet) 3 4 5 Long Bones-MICROSCOPIC ANATOMY ______________________-mature bones cells found in matrix in lacunae cavities Lacunae arranged in concentric circles called____________________around central(Haversian) canals _______________________(or Haversion system) is a complex of central canal and matrix rings Central canals run lengthwise through bony matrix to carry blood vessels and nerves to all of bone ______________________________-tiny canals that radiate outward from central canals to all lacunae-form a transportation system that connects all bone cells to nutrients in matrix -therefore well nourished _____________________________________run into compact bone at right angles to shaft and communicate from outside to interior Bone light in weight,but strong (Ca salts,collagen-give flexibility,but strength) 6 D. Bone Formation,Growth and Remodeling 2 most strong and supportive tissue-bone and cartilage Except for flat bones,most bones develop using hyaline cartilage as model ____________________-bone formation in 2 phases: 1. Hyaline cartilage model is completely covered by bone matrix(a “collar”) by bone forming _________________________.For a while,fetus has cartilage enclosed by bony bones.Enclosed hyaline cartilage model is digested away,forming a medullary cavity 7 2. By birth most hyaline converted to bone.except articular cartilage on ____________________and epiphyseal plates New cartilage is continually on the face of articular cartilages(covering bone ends) and epiphyseal plate surface that faces bone ends.At the same time,old cartlage abutting internal face of articular cartilage and the medullary cavity is BROKEN down and replaced by bony matrix Growing bones must widen as they lengthen---osteoblasts in ______________________add bone tissue to external face of diaphysis as osteoclasts in endosteum remove bone from inner face of diaphysis wall---both occur at same rate /circumference of long bone expands and bone widens….>______________________________growth--bone increasing in diameter. This is controlled by hormones –esp. growth hormones and ,during puberty , sex hormones Overall growth ends at puberty ,when _______________________________are converted to bone Long Bone Formation and Growth Figure 5.4a Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Bones dynamic and active tissue and continuously remodeled in response to : 1. Ca levels in blood-When blood Ca levels drop below homeostatic levels,the ____________________________in throat stimulated to release parathyroid hormones-______-into blood.PTH activates _____________________-giant bone destroying cells in bones to break down bone matrix and release Ca into blood. 8 If blood Ca levels are too high,Ca is deposited into bone matrix as Ca salts 2.In response to gravity and muscle mass-long bones retain normal proportions and strength and bones become thicker and form large projections to increase their strength where muscle is bulky….here _______________________lay down new matrix and become trapped w/in it….now,trapped, becoming osteocytes-mature bone cells Long Bone Formation and Growth Figure 5.4b Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Those that are bedridden and /or weakened lose mass.bone no longer subjected to stress and atrophy occurs Ca uptake and release and bone remodeling work together Rickets-look up p.141________________________________________________ ____________________________________________________ ____________________________________________________ ______________________________________ E.Bone Fractures Bones amazingly strong _____________________= breaks---in young due to activity level and in older people due to thin and weakened bones_ 1. Closed fracture-clean break that does not penetrate skin 9 2. _____________________________is when the broken bone breaks the skin Common Types of Fractures Table 5.2 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings A fracture is treated by ________________-where the realignment of break happens.In closed reduction,the ends are coaxed back into their position by M.D.For OPEN reductions,surgery is performed and pins or wires are used.After reduction it is _________________________by cast or tractionallowing healing to begin Simple fracture takes 6-8 weeks to heal….bot longer for large bones and bones of older people(due to their poorer circulation) 4 Events for bone repair: 1. Blood vessels are ruptured as the bone breaks…._________________________forms and blood cells deprived of nutrition die 2. The break is splinted by a ___________________________________________________________growth of new capillaries(granulation tissue) into hematoma at site of 10 damage./phagocytes dispose of dead tissue/as this happens, connective tissue of various types form a mass called fibrocartilage callus--containing some cartilage matrix ,some bony matrix, collagen and acts to splint the bone, closing the gap 3. bony callus forms-more osteoblasts and osteoclasts come to area and multiply-the fibrocartilage callus is gradually replaced by one made of spongy bone 4. Bone remodeling occurs-weeks to months-forms strong ,permanent bone patch at fracture site 11 HUMAN ANATOMY_SKELETON CONTINUED II. Axial Skeleton Forms longitudinal axis of body A. Skull Formed by cranium –protects brain and ____________________-hold eyes in anterior position and allow facial muscles to show expression All but one bone of skull is joined by ____________-interlocking , immovable joints(mandible has a freely movable joint) 1. Cranium-8 large ,flat bones ___________________________forms forehead,bony projections under eyebrows,and superior portion of orbit ____________________________paired,forms superior and lateral walls of cranium;include _________________________and ____________suture Temporal Bones(pair) lie inferior to parietal and join at ___________________________________ Temporal bone markings: a-External acoustic meatus- sound enters ear -leads to eardrum- and middle earb-Styloid process-sharp/,needlelike, attachment for many neck muscles c-__________________-process bridge of bone that joins with cheek bone(zygomatic bone) anteriorly d-Mastoid process-full of air cavities(mastoid sinuses)-rough projection posterior and inferior to external acoustic meatussome neck muscles attach here---The proximity to middle ear makes these sinuses a hot spot for infections__________________________---also could spread to the brain e-______________foramen allows passage of jugular vein(largest vein of head-drains the brain)/junction of temporal and occipital bones-anterior to this is the e_____________________________________-transmits cranial nerves VII and VIII-facial and vestibulocochlear nerves…. g- anterior to foramen is carotid canal that carotid artery brings most of the blood to the brain 12 Occipital bone-most posterior of cranium-floor and back wall of skull a._________________________suture joins this bone with parietals/base of bone b. ______________________magnum allows spinal cord to connect to brain c._____________________________________ rest on 1st vertebra/rockerlike on each side Sphenoid bone-butterfly shaped-spans width of skull and is some of floor of cranial cavity a. ________________________”Turk’s saddle”-encloses pituitary gland---depression in middle of spenhoid b. Foramen ovale allows cranial nerve v(trigeminal)to pass to chewing muscles of mandible. c. Parts form part of eye orbit-w/2 openings to eye d. 1-______________________allows optic nerve to pass and 2-_____________________through which cranial nerves III,IV,VI pass to control eye movement Many air cavities--_________________________________in central sphenoid Ethmoid Bone-anterior to sphenoid-roof of nasal cavity and part of medial walls of orbit a-__________________________”cocks comb”outermost covering of brain attaches here b-Small holes on each side of crista galli__________________________________-for olafactory nerves c-Extensions form superior and __________________________________________-lateral parts of walls of nasal cavity-and increase turbulence of air here(through nasal passages 2. facial bones-14 bones-12 are paired plus mandible and vomer Maxillae(maxillary)-2 fuse to form upper jaw-main – or keystone bones of the face-carry upper teeth in a)alveolar margin/alveolar processes b)palatine processes-form anterior part of hard palate of __________________c) ________________________sinuses drain into nasal cavity,lighten skull bones and amplify sound we make….mucosa continue into nose and throat and is a source of __________________________-infection of sinuses /headache and/or upper jaw pain 13 ______________________paired-posterior part of hard plate-failure to fuse medially is called ___________________________________ __________________________________cheekbonesalso border of eye sockets Lacrimal bones-finger-sized bones-part of medial wall of each orbit-each has a groove for tears(lacrimate) ________________________-small rectangular making bridge of nose—lower part is cartilage Vomer bone-single bone in median of nasal cavitymost of nasal septum Inferior nasal conchae-thin,curved-lateral walls of nasal cavity(project medially) _____________________-lower jaw-largest and strongest bone of face….meets temporal bone and is onlu freely movable joint of face ---lower teeth lie in ______________________ 3.Hyoid Bone-not really skull,but closely related to mandible and temporal bones-movable base for tongue and attachment for neck muscles/only bone that does not attach direactly w/ another bone/suspended in midneck region about 2 cmabove larynx-anchored by ligaments to styloid process of temporal/Hyoid has body and 2 pr of horns(cornua)that raise and lower larynyx when we swallow and speak *****Fetal Skull—face small compared to cranium,but skull large compared to infant’s body(1/8 of body length in adult and _____body length in infant 14 _________________________fibrous membranes connecting cranial bones-“soft spots’-allow compression during birth and allows for brain growth in late pregnancy and early infancy--fontanels replaced by bone by 2224 mos. after birth FETAL SKULL 15 16 17 B. Vertebral Column-Spine o Axial support of body-goes from skull(support) to pelvis-where it transmits weight o 26 irregular bones connected and reinforced by ligaments-resulting in flexible,curved structure o Surrounds and protects spinal cord o Before birth is 33 vertebrae-9 fuse to form __________________ and _________________________inferior vertebral column o There are 7 in neck_____________________________;12__________________________;and 5 in lower back-lumbar o Individual vertebrae separated by flexible pads of fibrocartilage_____________________________-allow flexibility and absorb shocks o Intervertebral discs 90 % water in youth and are spongy and compressible---water amount decreases w/ age and less compressible o _______________________disks is a slipped disc-occurs w/age and/or great twisting force/may come from twisting forces/can press on spinal cord or spinal nerves causing great pain o The discs and the “S” shape to spine function to prevent shock to head o The curvature in thoracic and sacral regions are called __________________________________because they are present at birth---a”C” in a newborn o The curvature in cervical and lumbar regions are called _______________________________________ because they develop when the baby is ready to walk(cervical appears when baby raises head)….see fig 518 o ABNORMAL SPINAL CURVATURES: (see p.154)_______________________,lordosis and __________________-may be congenital or from diseases…from poor posture or unequal muscle pull on spine. COMMON FEATURES OF VERTEBRAE 1. Body or ___________________-disclike,weightbearingfacing anteriorly 2. ____________________________arch formed from joining of all posterior extensions_________________________________ 3. ______________________________-canal through which spinal cord passes 4. Transverse processes-2 lateral projections from thr arch 18 5. ______________________________-single projection from post. Aspect of arch(= fused laminae 6. __________________________________________ __________________-paired projections Lateral to vertebral foramen-allows a vertebra to form joints w/ adjacent vertebrae Vertebral Regions: i. CERVICAL7 1st 2 atlas and___________.Atlas has no body;Transverse processes contain lg depressionsto receive occipital condyles of skull—allows nodding (“yes”)/Axis is a pivot for rotatopn of atlas and skull ______pivot point on axis Joint between____________allow you to rotate head from side to side(“no) C3 through C 7 lightest and smallest vertebrae;usually spinosous process short and in 2 branches______________________contain foramina(for vertebral arteries)-on way to brain ii. THORACIC12(T1-T12)-all typical Only vertebrae to articulate with ribs Body somewhat heart –shaped and has 2 costal facets(articulating surfaces) on ea. Side receiving heads of ribs 19 Transverse processes articulate w/knoblike tubercles of ribs Spinous process long and hooks sharply downward-(“giraffe’s head” from side) iii. Lumbar(L1-L5) o Massive blocklike bodies;short spinous processes (“moose head”) o Sturdiest vertebrae because receives most stress SACRUM(see sacrum picture 5.21) From fusion of 5 vertebrae Superiorly articulates w/L5 and inferiorly connects w/coccyx Winglike _________articulate laterally w/hip booone,making sacroiliac joints Posterior wall of pelvis _________________________________fused spinous process of sacral vertebrae Laterally-_________________________________ Sacral canal terminates in ______________________________opening COCCYX: Fusion of 3-5 tiny vertebrae Tailbone 20 21 C.THORACIC CAGE Sternum,ribs and thoracic vertebrae=______________________________,also called thoracic cage-protective cone around thoracic organs Sternum(breastbone) 22 Flat and is the fusion of 3 bones:______________________________________________ Attaches to the 1st 7 prs. of ribs Bony landmarks: 1. ______________________________concave upper border of manubriumlevel of T3 2. _____________________________from manubrium body meeting at slight angle to each other,making transverse ridge-level of 2nd rib 3. _______________________________-pt. where sternal body and xiphoid process fuse-level of 9th vertebrae _____________________________taking marrow sample at sternum for diagnoses of blood diseases Ribs-12 pairs All articulate with vertebral column and then curve downward ________________________-1st 7 pairs attach directly to sternum by __________________________________ __________________________-next 5 pairs either not attached to sternum or indirectly.Last 2 pair are called ______________________________sometimes(lack sternal attachment) Intercostals spaces attach to intercostals muscles-aid in breathing 23 24 III. Appendicular Skeleton 126 bones of limbs and pectoral or pelvic girdle(which attach limbs to axial skeleton) A. Bones of Shoulder Girdle 2 bones:______________________and _____________________ 1. CLAVICLE Also called ______________________ Slender ,doubly curved and attaches to manubrium and to scapula(shoulder joint Brace against arm touching top of thorax and helps prevent________________ w/o it shoulder caves in 2. SCAPULAE -shoulder blades-triangular and commonly called ____________________because they flare when we move our arms posteriorly Each has a flattened body with __________________process-enlarged spine of scapula-connects clavicle at acromialclavicular joint and beaklike _____________________________________ That points over top of shoulder and anchors some arm muscles ____________________________-serves as nerve passageway Scapula loosely held by trunk muscles 25 Scapula has 3 borders_______________________________________ _ and 3 angles:superior,inferior and lateral ________________________________-shallow socket receives head of arm bone-in lateral angle Shoulder girdle is light and allows upper limb free movement due to 3 factors: 1. each shoulder girdle attaches at one point to axial skeleton________________________________ 2. loose attachment of scapula allows it to slide back and forth against thorax as muscle attchment 3. ___________________________is shallow and shoulder joint is poorly reinforced by ligaments *****drawback to so much flexibility is ___________________________________________________ B.Bones of the Upper Limbs-30 bones-arms,forearms and hands 1. ARM Humerus-head fits into glenoid cavity,_________________________;2 bony projections separated by intertubercular sulcus and _______________________________________-sites of muscle attachment;also ____________________________-most frequently fractured part of bone;___________________________roughened area in midshaft-deltoid muscle attaches ;___________________________runs down posterior aspect of shaft,marking the place for the radial nerve;distal is the ________________-spool-like;ballike capitulum;coronoid and olecranon fossae-depressions that articulate w and medial and ______________________allow ulna to move freely when elbow is bent and extended 26 2.-forearm – _______________________-lateral bone on thumb side Both bones of forearm articulate at radioulnar joints 2 bones connected by ________________________________________ Both have _______________________at distal end ______________________________-below head-tendon of biceps muscle attaches ________________________medial bone on little finger side Proximal end has ___________________ and posterior olecranon process,separated by trochlear notch-grip trochlea 27 (like a pliers)of humerous pliers-like joint in 2. .hand-carpals,metacarpals and phalanges 8 _____________bones-2 irregular rows of 4 bones ea.-form carpus(wrist)-bound by ligaments to restrict movement between them(see 8 names p.1620) Palm consists of _____________________________#’ed 1-5(thumb side outward);heads are knuckles Ea. hand has 14 phalanges(3 ea. Finger-thumb has 2) Proximal,medial .and distal 28 C.bones of the Pelvic Girdleformed by 2 coxal(_____________________)-hip bones;form bony pelvis w/sacrum and coccyx bony pelvis=2 coxal bones,sacrum and coccyx; whereas pelvic girdle=2coxal bones and sacrum large and heavy and attached securely to axial skeleton via sacral attachment to lower lumbar,attaching to girdle___________________________ sockets deep and securely attached by ligaments most important function is ____________________________ and protect organs each hip bone formed by fusion of 3 bones:________________________________________ illium +connects posteriorly w/ sacrum____________________joint-forms most of hip bone;alae are winglike portions of ilia-upper portion= _____________________ and ends at anterior superior iliac spine and posteriorly w/posterior iliac spine ischium-_______________________-interior of coxal bone;________________________________roughened area receiving weight when sitting;ischial spine-superior to tuberosity-THIS NARROWS THE OUTLET OF PELVIS FOR PASSAGE OF BABY IN CHILDBIRTH ! ----____________________________allows blood vessels and lg sciatic nerve to pass from pelvis posteriorly into thigh--injections must stay clear of this area _______________________most anterior of coxal;__________________________________-opening that allows blood vessels and nerves to pass to ant. Thigh;each 29 pubis joins to form cartilaginous joint__________________________________ Ilium,ischium and pubis fuse at deep socket:__________________________________-“vinegar cup”-receives head of thigh bone Bony pelvis divided into false and true pelvis-which must large enough to allow passage of infants head in women for childbirth-_______________________measured by obgyn(outlet inferior and inlet superior) Individual pelvic measurements vary,but stark difference in male and female Female inlet larger and more circular Fem. pelvis as a whole more shallow and bones lighter and thinner Fem ilia flare more laterally Her sacrum shorter and less curved Her ischial spines shorter and farther apart-thus outlet larger 30 Her pubic arch rounder because angle of pubic arch greater D.Bones of Lower limbs-carry total body weight when erect-thus very thick and stronger 31 Thigh=________________heaviest and strongest bone of body Proximal has ball-like head,neck and _____________________________________________-separated anteriorly by intertrochanteric line and posteriorly by intertrochanteric crest-----along w/ gluteal tuberosity form sites for muscle attachment;head articulates w/ acetabulum-but also a big fracture site-esp. in elderly;slants medially to bring in line w/center of gravity;lateral and medial condyles distally-articulate w/tibia below……these condyles separated by deep intercondylar fossa/anterior is smooth ______________________-forms joint w/patella-knee 32 Leg -tibia and fibula connected by ______________________ ___________-tibia is shin bone-condyles proximally and articulate w/distal femur to make ________joint-patellar ligament attaches to _____________________distally________________ _____forms inner bulge of ankle-ant. tibia is sharpanterior border for muscles ________________-lies alongside tibia and joints proximally and distally-NO PART Of KNEE JOINTlateral malleolus outer part of ankle FOOT Tarsals,metatarsals and phalanges 33 Mostly carry body weight 2 most important functions_______________ ______________________ Tarsus-post. 1/2 of foot-7 tarsal bones ________________heelbone ______________lies between tibia and calcaneus 5 metatarsals and 14 phalanges-each toe has 3 phalanges and big toe has 2 Form 3 strong archesbound by ligaments and tendons(for muscles)-fallen arches or flat feet occur-see fig 5.35/p.165 34 IV.Joints= articulations *****Except for hyoid,all bones form joints with at least 1 other bone 2 functions:___________________________ and give rigid skeleton mobility 2 classifications;1)functionally-focuses on movement.There are ****__________________immovable and ________________________________slightly movable(1st 2 in axial skeleton) and _______________________freely movable(limbs) 2)structurally-based on whether fibrous tissue,cartilage or synovial joint cavity separate bony regionsfibrous,cartlagenous and synovial A. Fibrous Joints-united by fibrous tissue-ex. Sutures of skullbound by connective tissue fibers w/no movement 35 _______________________-connective fibers longer than sutures-so has more “give”-joint connecting distal sides of tibia and fibula B.Catilagenous Joints-connected by fibrocartilage-slightly movable-ex;pubic symphysis of pelvis and __________________________________pads of fibrocartilage—also epiphyseal plates and synarthrotic-immovable-joints of 1st ribs and sternum C. Synovial Joints-joint cavity contains synovial fluid 36 4 features: 1. _______________________________-hylaline-covers end of joint bones 2. _______________________________________-joint surfaces enclosed by sleeve of fibrous connective tissue and capsule lined w./synovial membrane 3. Joint cavity-articular capsule encloses a cavity-containing lubricating fluid 4. ______________________________-fibrous capsule reinforced w/ligaments _______________flattened fibrous sacs w/ thin film of synnovial fluidcommon where ligaments,muscles,skin,tendons or bones agitate __________________________elongated bursa that wraps completely around a tendon _________________________-bone forced out of normal position 37 C. Types of synovial joints based on Shape: o _____________________________-articular surface flat-short slipping and gliding-nonaxial—intercarpal wrist joints o _____________________________-cylindrical end of one bone fits into trough-shaped surface of another-angular movement in 1 plane----elbow,ankle and fingers-uniaxial-1axis o __________________________-rounded end of one bone fits into sleeve or ring of another of bone and maybe ligaments-uniaxial— 38 examples:proximal radioulnar joint and joint between atlas and _______________of axis o ____________________________”knuckle-like”—egg-shaped surface into oval cavity-side to side or back and forth-can’t rotate around long axis-biaxial-knuckle joints o Saddle joints-convex and concave area on both surfaces-thumbtwiddling thumbs o ____________________________head of one bone in round socket of another-multiaxial-shoulder and hips 39 Homeostatic Imbalance __________________________-inflammation of bursae or synovial membrane ________________________-ligaments or tendons damaged by stretching-or tornheal slowly due to poor blood supply 40 ________________________> 100 different inflammatory or degenerative joint diseases---possibly bacterial invasion(Acute arthritis) Chronic Arthritis __________________________(OA)-most common arthritis-chronic and degenerative ,typically affects aged(85%)-affects articular cartilage-cartilage softens,frays,and breaks down,exposed bone thickens and bone spurs grow on margin of joint-make crunching-___________________-noise----affects fingers,C and L spine and knees and hips;slow and irreversible,but rarely crippling;can be treated symptomatically for pain and inflammation….possible treatments(?)capsaicin or glucosamine sulfate ____________________________(RA)-a chronic inflammatory disorder-usually begins 40-50,but there is a juvenile form;3x as many women as men-many joints affected and usually symmetrically;course varies.It is _________________________destroy own tissue-trigger unknown;begins w/ inflammation of synovial membranes and fluid accumulates and destroy tissue;PANNUS-abnormal tissue clings to joint and erodes articular cartilage;scar tissue forms and ossifies and bone ends become formly fused________________________________-not all cases reach this stage.Treatment includes immunosuppressant drugs and symptomatic treatment ________________________-uric acid(normal waste of nucleic acid metabolism) accumulates in blood and may deposit as crystals in joints-extreme pain….more common in men,usually after 30-untreated bones fuse and joint is immobilized….several drugs prevent acute gout-colchicine,ibuprofen and dietary recommendations Osteoporosis-bonethinning-1/2 of women over 65-fractures easily---estrogen helps maintain bone health…also risks by smoking,poor diet and insufficient exercise 41 V.Developmental aspects Young fetus is _________________________ and fibrous membranes Bone growth along epiphyseal plates as one matures Changes from”C” spine to “S” spine __________________________-bone thinning disease- READ THIS SECTION AND TAKE ADDITIONAL NOTES 42 43