skeletal system Flashcards
cartilage
-one of 4 types of CT, contains no blood vessels or nerves, and is found in many parts of the skeleton
function of cartilage
cushioning and support of body structures, and shape maintenance
what are the 3 types of cartilage
-hyaline: forms most of the embryonic skeleton, covers ends of long bones and joint surfaces. ex. trachea, larynx
-fibrocartilage: pubic symphysis, intervertebral discs, menisci; strong
-elastic: flexible, returns to shape. ex external ear, epiglottis
bone function
provide levers on which muscles act to generate muscles
what are the forces that affect bones
-muscles contract
-gravity
-unloaded
-tension
-compression
-bending
-shear
-torsion
bones are structured to ________ forces acting upon them. and change…..
-resist
-change, size, and thickness to counteract forces with the help of vascularization.
the human skeleton is a _______ around which soft tissue of the body is arranged.
framework
functions of the human skeleton
protection, mobile, motile, strong, breakable, suscpetible to disease
other characteristics of the human skeleton:
-heavily vascularized produces RBS, somewhat regenerative, and has minimal innervation
-bone marrow inside; several
-outside CT is innervated; can feel pain from soft tissue
divisions of the human skeleton
-skull: formed by 28 bones, houses the brain and face; part of axial skeleton
-axial skeleton: trunk; includes ribs, sternum, vertebrae, pelvis, and coccyx
-appendicular skeleton: limbs, includes articulations to axial skeleton: pelvic and shoulder girdles. formed of long, irregular, short bones.
bones of the skull
-come in right and left pairs
-unpaired reside in the midline
appendicular skeleton: the arm
-scapula: 2 shoulder blade
-clavicle: 2 collar bone
-humerus: 2 upper arm
-radius and ulna: 2 each; forarm
-carpals: 16 wrist
-metacarpals 10
-phalanges28; fingers
appendicular skeleton: lower limb
-pelvis: 2 3 fused
-femur: 2 thigh
-tibia and fibula: 2 lower leg
-patella: knee 2
-tarsals: ankle 14
-metatarsals 10 and phalanges 28
axial skeleton bones
-sternum 1
-ribs 24
-vertebrae: cervical 7, thoracic: 17, lumbar: 5, sacrum 1, coccyc, 1
bone shapes; classification
-long bones
-short bones
-flat bones
-irregular bones
bone shapes; classification
-long bones
longer than wide, tubular; a shaft and two ends
ex. humerus and femur
bone shapes; classification
-short bones
cube shaped bones
ex. only wrist and ankle
-sesamoid bones: bones that develop within tendons
-ex. patella
bone shapes; classification
-flat bones
thin, flattened, and slightly curved, protect, produce RBC
ex. sternum, ribs, and most skull bones
irregular bones
bones with complex shapes, determined by articulation
-ex. hip bones and vertebrae
Muscle and ligament attachment points
-tuberosity
-trochanter
-tubercule
Muscle and ligament attachment points
-tuberosity
a large rounded projection, may be roughened. above surface
Muscle and ligament attachment points
-trochanter
a very large, blunt, irregularly shaped process, only present in the femor
Muscle and ligament attachment points
-tubercule
a small rounded projection or process
ligaments attached to muscles =
rough surface
bone to bone joint surface=
smooth surface
Muscle and ligament attachment points
-epichondyle
a raised area on or superior to a condyle (round articular area)
Muscle and ligament attachment points
-spine
a sharp, slender, often pointed projection
Muscle and ligament attachment points
-process
any bone prominence; small
depressions and opening in bones:
-foramen: a round or oval opening through a bone; nerve or vessels travel through it
-fissure: a narrow, slit like opening; nerves and vessels travel through
-fossa: shallow basin; contain something
-sinus: cavity within a bone, filled with air and lined with mucous membrane
bone projections that help form joints
-condyle: a rounded articular projection, often correlates with a corresponding fossa- joint surface
-facet: a smooth nearly flat articular surface where two bones come together
-head: bony expansion carried on a narrow neck- away from the shaft
two types of bone
-compact bone: a dense outer layer that appears smooth and solid, around sponge
-spongy (trabecular) bone: found internally deep to compact layer; a honeycomb network of small pointed flat pieces called trabeculae, where the open spaces are filled with bone marrow
structure of a typical long bone
-diaphysis
a tubular shaft of a bone, core of a bone
-has a medullary cavity: filled with bone marrow, where RBC is made and stored
structure of a typical long bone
-epiphysis
ends of a bone, covered with articular cartilage, bones grow from ends
structure of a typical long bone
-blood vessels
bone tissue is well vascularized
structure of a typical long bone
-periosteum
a well innervated and vascularized CT membrane that covers the outer surface fo each bone except the epiphyseal ends
structure of short, irregular, and flat bones
-similar to long bones : periosteum covered compact bone externally with and endosteum covered spongy bone internally
-contain BW between trabeculae but no marrow cavity is present
-have no shaft and epyphysis
-diploe: internal spongy bone of flat bones, found in the skull
bending compresses the bone on one side and does what to the other?
stretches the other side
compression and tension are greatest at
external surfaces
to resist stress:
-strong compact bone is found on the external portion of the bone
-the trabeculae of spongy bone align along stress lines in a support pattern
structural classifications of joints: (material uniting the joint)
-fibrous
-cartilaginous
-synovial
functional classifications of joints: (movement)
-synarthrosis
-amphiarthrosis
-diarthrosis
structural joint:
-fibrous joint
bones united by fibrous CT
-ex. cranial vault structures, syndesmoses, gomphoses
structural joint:
-cartilagenous joint:
bones united by hyaline cartilage (synchrondroses) or fibrocartilage (symphyses), strong and less mobile
-ex. epiphyseal plates, intervertebral discs, pubic symphysis
functional classifications of joints:
-synarthrosis
immovable
-ex. cranial vault sutures
functional classifications of joints:
-amphiarthrosis
slightly moveable
-ex. IV discs, pubic symphysis of pelvis
functional classifications of joints:
-diarthrosis
bone articulation permits free motion, most common
-ex. glenohumeral joint
synovial joint:
-fibrous joint capsule lined with synovial membrane which forms a synovial cavity; weight bearing surfaces lined with articular cartilage
-most common and important
-present in limbs
-outside: ligaments, tendons nerves
key element with synovial joints
unites at least two bones that contains a synovial joint capsule outside, with synovial fluid inside, articulating cartilage, and includes hyaline cartilage in the bones.
synovial joint classifications based on shape
-plane, hinge, pivot, condyloid, saddle, ball and socket
synovial joint shapes
-plane joints
short gliding movements
-flat cube shapes bones
-moves any axis
location: wrist bones and ankle
synovial joint shapes
-hinge joints
allow angular movements
-uniaxial movement: flexion and extension
location: elbow
synovial joint shapes
-pivot joints
allow rotational movements
-associated with pronation and supination
location: wrist and elbow
synovial joint shapes
-condyloid joints:
abduction, adduction, flexion, extension
location: phalanges
synovial joint shapes
-saddle joint
abduction, adduction, flexion, extension
-more restrictive, narrow window
-location: first carpometacarpal joint in the ball of the thumb
synovial joint shapes
-ball and socket joint
movements in all directions
-location: shoulder
trade of between joint stability and mobility
multiaxial: less stable, more mobile
uniaxial: most stable, less mobile
ossification
bone tissue formation, begins in the embryo and proceeds to adolescence and slower at adult.
Week 8 in embryo
bone tissue first develops and replaces hyaline cartilage and some membranes of the mesenchyme
membrane bones in embryo
formed directly from mesenchyme; all bone of the skull except fo rbase
intramembranous ossification
-endochondral ossification: all the other bones inferior to the basicranium, except for clavicles, dev. as hyaline cartilagem
during childhood and adolescence
-bone lengthen entirely by growth of epiphyseal plate
-cartilage is replaced with bone as quickly as it grows
-epiphyseal plates maintain constant thickness
-the entire bone lengthens
simple fracture
the bones break cleanly but does not penetrate the skin
compound fracture
the broken ends of the bone protrude through the skin
comminuted facture
bone fragments into three or more pieces
-older age, lost mineral content
compression fracture
bone is crushed
-more common in brittle
spiral fracture
ragged break occurs when excessive twisting forces are applied to a bone
sports
debilitating, takes a long time to hear
epiphyseal fracture
epiphysis separates from the diaphysis along the epiphyseal plate
-tends to occur where cartilage cells are dying and calcification of the matrix is occuring
depressed fracture
broken bone is pressed inward
-skull
greenstick fracture
bone breaks incompletely, only one side breaks
