BIO120 APPENDICULAR SKELETON

how many bones are there in the appendicular skeleton?

126 bones

what does the appendicular skeleton compose of?

the pectoral (shoulder) girdles, pelvic, and appendages

what does the pectoral (shoulder) girdle consist of?

the anterior clavicle and posterior scapula

what are the 3 causes for the shoulder girdle's great mobility?

the sternoclavicular joint is the only attachment to the axial skeleton, loose attachments of the scapula allow sliding due to muscular activity, and the shallow glenoid cavity gives little stability for the shoulder joint

what can the flexibility of the shoulder girdle lead to?

easy dislocation of the humerus

clavical

collar bone. if fractured, the upper arm is disabled. acts like a strut

acromial (lateral) end of clavicle

the end that articulates with the acromion of the scapula to form the acromioclavicular (AC) joint

sternal (medial) end of clavicle

articulates with the sternum to form the lateral walls of the jugular notch

conoid tubercle of clavicle

anchors ligaments

medial (vertebral) border of scapula

thin, long border that runs parallel to the vertebral column

lateral (axillary) border of scapula

thick border that is closest to the armpit, ends superiorly with the glenoid cavity

glenoid cavity

shallow socket that holds the humerus. ball and socket joint

corocoid process

attachment point for muscles of upper limbs

suprascapular notch

allows nerves and blood vessels to pass

spine

ridge of bone on the posterior surface, felt through the skin

acromion

articulates with the acromial (lateral) end of the clavicle to form the acromioclavicular (AC) joint

intertubercular sulcus

groove separating the greater and lesser tubercles of the humerus, tendons of the biceps brachii lie in this groove

deltoid tuberosity

attachment site of the deltoid muscle

deltoid muscle

connected to the deltoid tuberosity

radial fossa of humerus

receives head of radius when the forearm is flexed

coronoid fossa of humerus

receives the coronoid process of the ulna when the forearm is flexed

capitulum

condyle that articulates with the radius

trochlea

condyle that articulates with the ulna

medial epicondyle

has the ulnar nerve running in a groove beneath it, aka the funny bone

lateral epicondyle

small condyle proximal to the capitulum

olecranon fossa

accommodates the olecranon process of the ulna

antebrachium

forearm, 2 bones: radius (lateral) and ulna (medial)

radius

articulates with the humerus and ulna proximally, articulates with the carpals (scaphoid + lunate) distally

head of radius

articulates with the capitulum of the humerus

radial tuberosity

point of attachment of the biceps brachii

styloid process of radius

attachment for ligaments of the wrist

ulnar notch of radius

accommodates the head of the ulna (radius + ulna connects here at the distal end)

olecranon process of ulna

articulates with the olecranon fossa of the humerus when the forearm is extended

trochlear notch

articulates with the humerus

coronoid process of ulna

articulates with the trochlea of the humerus

styloid process of ulna

attachment point of ligaments of the wrist

whare the 3 groups of bones in the manus/hand?

carpals (8), metacarpals (5), and phalanges (14)

carpal bones

8 carpals, 2 irregular rows of 4 bones

carpal bones from proximal row, medial to lateral in anatomical position

pisiform, triquetrum, lunate, and scaphoid, all bound together by ligaments; Please Try Learning Skills

carpal bones distal row, medial to lateral

hamate, capitate, trapezoid, and trapezium; Haters Can't Touch This

metacarpals

numbered 1 to 5 from the thumn (pollex) to the pinky, forms the palm of the hand, the head of the metacarpals become knuckles when the hand is in a fist, labeled as 1st metacarpal (right), etc.

phalanges

singular is phalanx, number 1 to 5 from pollex to the pinky, includes the proximal, middle, and distal phalanges. the thumb only has proximal and distal

pelvic girdle

consists of 2 coxal bones, the ossa coxae sacrum and the coccyx. the coxal bones are heavy + massive, attached to the axial skeleton

what is the main function of the pelvic girdle?

weight bearing

each coxal bone is a fusion for which 3 bones?

ilium, ishcium, and pubis

acetabulum

receives the head of the femur, "wine cup", allows movement

ilium

largest of the pelvic bones, connected to the sacrum, comprises of the superior + posterior portion of the pelvis

iliac crest

thick superior margin of bone, felt when you place hands on hips

greater sciatic notches of ilium

allow passage of blood vessels and sciatic nerve

iliac fossa

shallow depression/internal surface of the ilium

sacroiliac joint of ilium

joint where the sacrum meets the ilium

auricular surface of ilium

articulates with the sacrum

arcuate line of ilium

borderline between true and false pelvis

ischium

comprises of the inferior and posterior portion of the coxal bones

ischial tuberosity

bears the weight of the body while sitting

lesser sciatic notch

allows passage of blood vessels and nerves to and from the femur

ischial ramus

narrow portion of the bone that articulates with the pubis

superior pubic ramus

superior extension of the body on the pubis

obturator foramen

allows blood vessels and nerves to run from the pelvic cavity to the thigh

pubic crest

formed by the two pubic bones at the pubic symphysis, forms the pubic arch below

pubic arch

angle formed by the left and right inferior rami of the pubic bones

pubic symphysis

fibrocartilage pad that holds the two pubic bones together, absorbs shock from the weight of the upper body

pubic tubercle

attachment point of the inguinal ligament

articular surface

surface of each pubis that combines with fibrocartilage to form the pubic symphysis

false pelvis

superior to the arcuate line, supports the abdominal viscera

true pelvis

inferior to the arcuate line

pelvic inlet/ brim

opening from the sacral promontory and the arcuate lines

pelvic outlet

inferior margin of the true pelvis

what is the function of the female pelvis?

child bearing, hold reproductive organs

what is the function of the male pelvis?

support heavy bones, hold reproductive organs

what is the true pelvis of females like?

wider, oval from side to side

what is the true pelvis of males like?

narrower, deeper

what is the pubic arch of females like?

80 to 90 degress, broader

what is the pubic arch of males like?

50 to 60 degress, narrower

what is the pelvic inlet/brim of females like?

wider/more oval

what is the pelvic inlet/brim of males like?

narrower, heart shaped

what is the coccyx of females like?

more movable, projected more inferiorly

what is the coccyx of males like?

less movable, projected more anteriorly

what is the pelvic outlet of females like?

wider

what is the pelvic outlet of males like?

narrower

what is the sacrum of females like?

wider/shorter

what is the sacrum of males like?

narrower/longer

what is the acetabulum of females like?

smaller, further apart

what is the acetabulum of males like?

larger, closer together

what are the bones of the female pelvis like?

lighter/thinner

what are the bones of the male pelvis like?

heavier, thicker

what is the tilt of the female pelvis?

more tilted forward

what is the tilt of the male pelvis?

less tilted forward

femur

thigh bone, heaviest and strongest bone in the body

head of femur

ball like, articulates with the acetabulum of pelvic girdle

fovea capitis

small pit in the head of the femur, attachment of small ligaments

neck of femur

weakest point and prone to hip fractures

greater and lesser trochanters

site for muscle attachment

gluteal tuberosity

site of muscle attachment

linea aspera

long vertical ridge of bone on the posterior shaft of the femur

medial and lateral supracondylar lines

two lines that diverge from the linea aspera and travel to their respective condyles

medial and lateral condyles of femur

articulate with the meniscus/tibia, each condyle has a corresponding epicondyle

intercondylar fossa

deep depression between the condyles of the femur, beneath the popliteal surface

adductor tubercle

attachment site for the adductor magnus muscle

patellar surface

articulates with the patella