Anatomy Test 2

Fractures

any break in bone

classification of fracture

direction of fracture line: linear or transverse

skin broken (compound = open); skin not broken (closed = simple)

position of bone ends (displaced or nondisplaced)

common fractures

colles fracture

potts fracture

closed reduction: bone fragment manipulated w/o surgery

open reduction: surgery w plates, screws, and pins

stress fracture: break due to repeated strains (microscopic)

pathologic fracture: break associated w weakened bone

colles fracture

occurs at distal radius, common in osteoperosis

potts fracture

distal tibia, fibula, or both

repair of bone

1) formation of fracture hematoma

2) fibrocartilaginous callus formation

3) bony callus formation

4) bone remodeling

joints

how individual bones join (articulate) to permit. body movement

joint classification

-structural classification: type of CT binding the bones, presence/absence of synovial cavity (fibrous, cartilaginous, synovial)

-functional classification: type of movement permitted within joint

• synarthrosis: no movement

• amphiarthrosis: slight movement

• diarthroses: freely moveable

-fibrous joints are generally immoveable whereas synovial joints are moveable

-synarthrosis + amphiarthrosis: restricted movement → support + protection (axial skeleton)

-diarthrosis: free movement (limbs)

fibrous joints

bones held by dense irregular CT

-no synovial cavity

-little material separates bone → synarthrosis or amphiarthrosis

-types: suture, syndesmoses, gomphoses, interosseous membrane

suture

-bone edges have grooves → close and firm fit together → short connecting fibers span small gap

-synarthrosis (amphiarthrosis in children)

*some sutures, fibers may be replaced by bone = synotosis

location of sutures

between flat bones of skull

syndesmoses

held by fibrous CT, but bone ends are farther apart → longer fibers (ligament) → a give between bones

-amphiarthroses

location of syndesmoses

between distal ends of tibia + fibula (allows for supination and pronation)

gomphoses (could be classified as syndesmoses)

peg-and-socket articulation

-location: roots of teeth in alveolar sockets

-synarthrosis (if no disease)

interosseous membrane

-also could be type of semidesmoses

-sheet of CT that binds neighboring long bones

-location: radius — ulna, tibia — fibia

cartilaginous joints

bones united by cartilage

lack synovial fluid

allow little/no movement

types: synchondroses, symphyses

synchondroses

-hyaline cartilage holds bone together

-synarthroses

-locations - temperorary, forming epiphyseal plates

-temporary between 1st rib and manubrium (eventually replaced by bone - synostoses)

-between ribs 2-10 and their costal cartilage

symphyses

fibrocartilaginous pads separating the hyaline cartilage of adj. bones

amphiarthroses (compressible → slight movement)

location: between 2 pubic bone (symphysis pubis), intervertebral disc

synvoial joints

-most joints

-fluid filled joint cavity (synovial cavity)

-diarthrosis: only limited by ligaments, muscles, tendons, and bones

-distingushing features: articular cartilage, synovial cavity, synovial fluid, articular capsule

articular cartilage

thin hyaline cartilage layer covering bone articular surface → reduce friction between bones

synovial cavity

small space separating the articulating bone ends, filled w synovial fluid

synovial fluid

thick fluid produced by the synovial membrane

-nourishes, lubricates cartilage, prevents articular cartilage contact (^ prevent their erosion)

• Normally = thin film over joint surfaces

injury or inflammation (synovial joint)

increase production of synovial fluid → swelling

articular capsule

surrounds and encloses synovial cavity

-double layered

i) fibrous membrane

ii) synovial membrane

fibrous membrane

part of articular capsule, joined to periosteum

synovial membrane

part of articular capsule

-inner layers, folds, lines, cavity

• produces synovial fluid

• not covering articular cartilage or disc surface

additional features of some synovial joints

1) supporting ligaments

2) articular discs

3) labrum

supporting ligaments (synovial joints)

-intrinsic - capsular ligaments; parallel fiber bundles within the outer fibrous layer

-extracapsular ligaments - outside capsule, extend from bone to bone (ex. collateral ligaments of knee)

-intracapsular ligaments - inside synovial cavity (ex. cruciate ligaments of knee)

articular discs

-fibrocartilage extending inward from capsule

-divide synovial cavity into 2 spaces

-absorbs shock and pressure (menisci of knee)

labrum

fibrocartilage lip that deepens the joint socket

muscles and tendons crossing the joint also stabilize

true

synovial membrane structures

-bursae

-tendon sheath

bursae

-flattened, pouch-like synovial membrane sacs filled w synovial fluid

-bonion = enlarged bursa at big toe

where are bursae’s located?

-some subq (between bone and skin), most between tendons and bone

tendon sheath

-facilitates gliding of tendon as it traverses a tunnel (bony or fibrous)

-modified tube-like bursa

structure of tendon sheath

double-walled cushion

-visceral layer of synovial memb folds over tendon surface

-parietal layer lines the formed tunnel

tendon sheath is associated with

strong flexor muscles

limiting factors of movement (synovial joint)

bone structure, ligament tension, associated muscle's’, tension, size, arrangement

movements of synovial joints

-uniaxial: only one axis of motion (elbow knee)

-biaxial: 2 planes of movement (at right angles to e/o)

-triaxial: movement in 3 planes (multiaxial)

-nonaxial: movement do not follow particular axis (smaller joints)

types of movement at synovial joint

gliding, angular movement, rotation, special movement

gliding

simple motion where surfaces of adjoining move back and forth in relation to e/o

ex. carpal, tarsal

angular movement

-up or down movement between 2 bones moving in a single plane

-4 types of angular movement

• flexion

• extension

• abduction

• adduction

• circumduction

flexion

bone moved in posterior anterior plane, decrease angle between it and adj bone

-ex, bending elbow, bringing thigh towards abdomen (hip flexion), calf toward back of thigh (knee flexion)

dorsiflexion

ankle flexion (raising toe towards shin)

extension

increase angle between adj bones (when flexed joint is moved back to anatomical position)

ex. straighten arm or leg

hyperextension

movement beyond the straight position

-bring limbs posterir

plantar flexion

-type of extension

-bend ankle to lower toe region

abduction

-body moved away from midline

-ex. moving fingers away from midline of hand (move away from 3rd finger)

adduction

movement towards the midline of body (hand/foot)

circumduction

joint motion delineates a cone (apex of cone in articular cavity)

-sequential combo of flexion, abduction, extension, and adduction (ex. hip, shoulders)

rotation (pivot joint)

motion of bone around a central axis w/o any displacement of that axis

-ex. supination (outward rotation of forearm (palm face up, radius/ulna parallel), pronation (inward rotation of forearm → palm faces downward/backward → distal end of radius crossing over ulna)

special movements

elevation

depression

elevation

raises bones vertically ex. mandible and clavicles

depression

lowers bone

opening jaw, shrugging shoulders

protraction

bone moves forward in horizontal plane

ex. mandible, shoulders (blades)

retraction

posterior movement of protracted part

lateral excursion

sideways movement

ex. jaw

medial excursion

movement back to midline

opposition

thumb movement to touch or approach fingertips

reposition

thumb movement back to anatomical position

inversion

foot sole turned medially

eversion

foot sole turned laterally

types of synovial joints

6 types of movements

plane joints, hinge joints, pivot joints, condyloid joints, saddle joints, ball and socket joints

plane joints (athrodial, gliding)

-nonaxial

-opposition of flat articular surface

-movement: side to side, back and forth gliding

location of nonaxial joints

articular processes of vertebral, between carpals, between tarsals

hinge joints

convex surface of one bone fits in concave surface of another

-allows for flexion and extension

-location: knees, elbows, interphalangeal joints

-uniaxial

pivot joint

-movement: rotation around longitudinal axis of bones

-uniaxial

location of pivot joints

1) c1 vertebrae (atlas), 2) c2 vertebrae (axis), radial/ulnar joint (supination/pronation)

condyloid (ellipsoid joint)

-one articular surface is concave and other is sl. convex

-movement in 2 planes (biaxial), flexion/extension, abuduction/adduction, circumduction

location of condyloid joints

radius/carpal, occipital condyle, C1, metacarpophalangeal jts, metatarsalphalangeal jts

saddle joints

same movement as condyles

biaxial

saddle joint example

carpometacarpal joint of thumb (trapeziometacarpal jt)

ball and socket joints

-multiaxial

-spherical head of one bone fits into cup-shaped cavity of other

-movement: flexion/extension, abduction/adduction, circumduction, medial/lateral rotation

location of ball and socket

shoulder, hips

ligaments of elbow

annular ligament: encircles head of radius and holds it against ulna

ulnar collateral ligament: connect humerus to ulna

radial collateral ligament: connect humerus (deep to annular) to radius

ligaments of knee

cruciate ligament

collateral ligament

tranverse ligament

ligaments of the hip

iliofemoral ligament

ischiofermoral ligament

pubofermoral ligament

athroplasty

replacement of a joint (hip)

rheumatoid athritis

painful autoimmune disease, attack lining of joints, hurts in the morning

osteoarthritis

wear and tear, knee/big joints

-gets worse throughout the day

gouty athritis

uric acid deposited in soft tissue of the joints

sprain

torn ligament

price for sprain

protection, rest, ice, compress, elevate

strain

torn tendon

dislocation

displacement of a bone from a joint

-elbow most common in children

athralgia

pain in joint

bursectomy

removal of bursa

chondritis

inflammation of cartilage

sublaxation

partial/incomplete dislocation

osteopenia

weakening of bone (bone mineral less than normal), can lead to osteoperosis)

osteosarcoma

rare aggressive tumor that begins in bone forming cells and creates immature bone tissue (osteoids)

endoskeleton

lies within soft tissues of the body

axial skeleton

bones of head, vertebral column, ribs and sternum

appendicular skeleton

bones of the extremeities, bones of pectoral/pelvic girdle

basic function of skeleton (206)

1) protect

2) support

3) movement (levers which muscles act on)

4) mineral resevoir: Ca++, PO4-, Mg-, electrolyte balance

5) hemopoesis (blood cell formation)

6) triglyceride storage (yellow BM)

chemical comp of bone

type of ct, composed of living cells + intercellular matrix

-inorganic and organic parts

organic component of bone

GAGs, collagen fibers (osteoids - devoid of minerals for bone)

-help resist stretching, tensile strength, add flexibility + support

-CELLS ARE ORGANIC (osteoclast, osteoblast, osteocyte)

inorganic component of bone

mineral salts (ex. calcium phosphate + calcium hydroxide → hydroxyapetite: hardening mineral) provides compressive strength (cement)

osteoblast, osteoclast, osteocyte

osteoblast: build/produce bone

osteoclast: carve/breakdown bone

osteocyte: mature cells

classification of bone

according to their shape

-long bone, short bone, irregular bone, flat bone, sesamoid bone, structural bone