MIDTERM IBS - APPENDICULAR SKELETON

What is the function of the pectoral (shoulder) girdle?

attach the bones of the upper limbs to the axial skeleton

What bones make up each pectoral girdle?

clavicle and scapula

Do the pectoral girdles articulate with the vertebral column?

No

How are the scapulae held in position?

Muscles that extend from vertebral column and ribs to the scapula

Where is the clavicle located?

• lies horizontally across the anterior part of the thorax

• superior to the first rib

What are the characteristics of the clavicle along its length?

Subcutaneous (under skin) and easily palpable (can be touched) along its length

What is the sternal end of the clavicle?

rounded medial end

What does the sternal end of the clavicle articulate with?

manubrium of the sternum

What joint is formed by the sternal end of the clavicle and the manubrium?

sternoclavicular joint

What is the acromial end of the clavicle?

broad, flat lateral end of clavicle

What does the acromial end of the clavicle articulate with?

acromion of the scapula

What joint is formed by the acromial end of the clavicle and the acromion?

acromioclavicular joint

What is the scapula (shape and type)?

large, triangular, flat bone

Where is the scapula situated?

• superior part of the posterior thorax

• between the levels of the 2nd and 7th ribs

What is the spineous process of the scapula?

• prominent ridge

• runs diagonally across the posterior surface of the scapula

What is the acromion process?

expanded process of the spine

What does the acromion process articulate with?

acromial end of the clavicle

What is the glenoid cavity?

shallow depression inferior to the acromion

What does the glenoid cavity accept?

head of the humerus

What joint is formed by the glenoid cavity and the head of the humerus?

glenohumeral (shoulder) joint

What is the medial (vertebral) border of the scapula?

thin edge of the scapula closer to the vertebral column

What is the lateral (axillary) border of the scapula?

thick edge of the scapula closer to the arm

What is the superior border of the scapula?

superior edge of the scapula

What is the scapular notch?

prominent indentation on the superior border

What passes through the scapular notch?

suprascapular nerve

What is the coracoid process?

Projection of the anterior surface of the superior border of the scapula

What attaches to the coracoid process?

tendons and ligaments

Which bones make up the upper limb (upper extremity)?

humerus

ulna and radius

carpals - 8 in the carpus (wrist)

metacarpals - 5 in the metacarpus (palm)

phalanges - 14 in the digits (fingers).

What is the humerus?

Sole bone of the arm

between the scapula and elbow.

What is the proximal end of the humerus like?

roughly cylindrical

What is the head of the humerus?

Rounded head

What does the head of the humerus articulate with?**

glenoid cavity

What is the anatomical neck of the humerus?

oblique groove distal to the head

What is the greater tubercle of the humerus?

Lateral projection distal to the anatomical neck

What is the lesser tubercle of the humerus?

Anterior projection distal to the anatomical neck

What is the surgical neck of the humerus?

Constriction in the humerus, distal to the tubercles

What is the intertubercular sulcus?

Groove between the two tubercles

What is the deltoid tuberosity?

V-shaped area laterally, at the middle portion of the shaft

What attaches to the deltoid tuberosity?

deltoid muscle tendons

Where is the radial groove located?

posterior surface of the humerus

Where does the radial groove run?

Along the deltoid tuberosity

What does the radial groove contain?

radial nerve

What is the distal end of the humerus like?

broad and flattened

What does the distal end of the humerus articulate with?

ulna and radius to form the elbow joint

What are the medial and lateral epicondyles?

Rough projections on either side of the distal end of the humerus

What is the function of the medial and lateral epicondyles?

attachment point for most of the muscles

Where can the ulnar nerve be palpated?

above the posterior surface of the medial epicondyle.

What is the capitulum?

rounded knob on the lateral aspect of the distal humerus

What does the capitulum articulate with?

head of the radius

Where is the trochlea located?

medial to the capitulum

What does the trochlea articulate with?

trochlear notch of the ulna

What is the radial fossa?

anterior depression above the capitulum

What articulates with the radial fossa during forearm flexion?

head of the radius

What is the coronoid fossa?

anterior depression of humerus

What does the coronoid fossa receive during forearm flexion?

coronoid process of the ulna

What is the olecranon fossa?

Posterior depression of humerus

What does the olecranon fossa receive during forearm extension?

olecranon of the ulna

On which side of the forearm is the ulna located?

medial aspect of the forearm, on the little-finger side

How does the ulna compare in length to the radius?

ulna is longer than the radius

What is the olecranon of the ulna?

forms the prominence of the elbow

What is the coronoid process of the ulna?

anterior projection of the olecranon

What does the coronoid process of the ulna articulate with?

humerus trochlea

Where is the ulnar tuberosity located?

inferior to the coronoid process

What attaches to the ulnar tuberosity?

biceps brachii muscle

What is the radial notch of the ulna?

depression inferior to the trochlear notch

What does the radial notch articulate with?

head of the radius

What does the distal head of the ulna articulate with?

ulnar notch of the radius

Where is the styloid process of the ulna located?

on the posterior side

What attaches to the styloid process of the ulna?

ulnar collateral ligament to the wrist

On which side of the forearm is the radius located?

lateral aspect of the forearm, on the thumb side

What are the characteristics of the radius?

narrow proximal end and broad distal end

What is the head of the radius like?

Disc-shaped

What does the head of the radius articulate with?

capitulum of the humerus and the radial notch of the ulna

Where is the neck of the radius located?

inferior to the head

What is the radial tuberosity?

roughened area inferior to the neck - radius

What attaches to the radial tuberosity?

tendons of the biceps brachii muscle

What are the key features of the distal radius?

• Ulnar notch (articulates with the head of the ulna) narrow concavity

• styloid process (thumb side, attaches brachioradialis and radial collateral ligament)

What is the most common fracture in adults?

Fracture of the distal end of the radius

What is the interosseous membrane?

broad, flat, fibrous connective tissue

joins shafts of the ulna and radius

What are the proximal and distal radioulnar joints? **

• proximal: radius head articulates with the ulna’s radial notch

• distal: ulna head articulates with the radius’s ulnar notch

What forms the radiocarpal (wrist) joint?

distal radius articulates with lunate, scaphoid, and triquetrum

distal ulna is separated from wrist by a fibrocartilage disc

What is the carpus, and how is it arranged?

proximal region of the hand

8 small carpal bones - arranged in two transverse rows of four

joined by ligaments

What are intercarpal joints?

Articulations among carpal bones

What are radiocarpal (wrist) joints?

Articulates with the distal ends of the ulna and radius

Which bones form the proximal row of carpals?

• scaphoid (boatlike)

• lunate (moon-shaped)

• triquetrum (triangular)

• pisiform (pea-shaped)

Which bones form the distal row of carpals?

• trapezium (little table)

• trapezoid (four-sided)

• capitate (head-shaped)

• hamate (hooked)

What is the metacarpus, and how are its bones numbered?

intermediate region of hand (palm)

5 metacarpals numbered I–V, starting with the thumb

What are the parts and articulations of a metacarpal bone?

proximal base articulates with the distal carpal row - form carpometacarpal joint

distal head articulates with proximal phalanges - form metacarpophalangeal joints

What are phalanges, and how many are there?

• bones of the digits, distal part of the hand

• 14 phalanges in the 5 digits

How are phalanges arranged in the fingers and thumb?

3 - proximal, middle, and distal

thumb has NO middle phalanx

What are the parts of a phalanx?

proximal base, shaft, distal head

What are the joints between phalanges called?

Interphalangeal joints

What forms the pelvic (hip) girdle, and what are its functions?

pair of hip bones

• support vertebral column and visceral organs of the pelvis

• connect the bones of the lower limbs

What are the hip bones also called?

Coxal bones - coxa - pelvic bones

How do hip bones develop?

In newborns, each consists of 3 bones separated by cartilage:

• superior ilium, anterior pubis, posterior ischium

• fuse by age 23

Where do the hip bones unite? Anteriorly and posteriorly?

anteriorly - pubic symphysis

posteriorly - sacrum at the sacroiliac joints

What structures compose the bony pelvis?

• deep (basin-like) structure forming a complete ring

• pair of hip bones (ilium, pubis, and ischium)

• pubic symphysis

• sacrum

• coccyx

What are the two parts of the ilium, and what is the iliac crest?

ilium - superior ala and inferior body

iliac crest superior border of ilium

What are the four iliac spines?

anterior superior iliac spine (blunt)

anterior inferior iliac spine (below it)

posterior superior iliac spine (sharp)

posterior inferior iliac spine (below it)

What is the function of the iliac spines?

attachment points for muscles - trunk, hip, thighs