Skeletal system IV

appendicular skeleton

pectoral (shoulder) girdle, upper limb, pelvic girdle, lower limb

pectoral girdle

connects upper limbs to trunk of body; clavicle, scapula, allow for attachment points of muscles; upper limb movement

clavicle

collarbones, sensitive to muscle pull; susceptible to Fractures, attachment site for muscles, braces (hold scapula and arms laterally, away from superior part of thorax), transmit compression forces from upper limbs to axial skeleton

scapula

shoulder blades, triangular on posterior side

glenoid cavity

where humerus (arm bone) and scapula meet

acromion process

point where shoulder joins with clavicle

upper limbs

30 separate bones; three regions: arm, forearm, hand

humerus

main bone; arm region, typical long Bone, between scapula and elbow

ulna

forearm region, medial bone of forearm between elbow and wrist; forms elbow joint

radius

forearm region; lateral bone of forearm (towards thumb); carries wrist

carpal

upper limb hand, bones of wrist, arranged in 2 rows

metacarpals

upper limb hand, bones of palm; one in line with each digit

phalanges

upper limbs hand, bones of fingers/digits; 3 in digits 2-5 and 2 in thumb/pollex

parts of phalanges

distil, middle, proximal

pelvic girdle/hip

transmit weight of upper body to lower limbs and protects visceral organs, some of strongest ligaments, sockets in hip are deeper than shoulder, composed of 2 hip bones held together by cartilage called pubic symphysis