Skeletal System 7.10

upper limb

bones of the upper limbs

humerus, radius, ulna, carpals, metacarpals, and phalanges

humerus

long bone that extends from the scapula to the elbow

upper end has a smooth, rounded head that fits into the glenoid cavity of the scapula

below the head are two processes-a greater tubercle on the lateral side and a lesser tubercle on the anterior side

tubercles provide attachments for muscles that move the upper limb at the shoulder

between them is a narrow furrow, the intertubercular sulcus (intertubercular groove)
narrow depression along lower margin of the humerus that separates it from the tubercles called the surgical neck (many fractures occur here)

near middle of bony shaft on the lateral side is a rough, V-shaped area called the deltoid tuberosity —> provides attachment for the deltoid

at lower end of the humerus are two smooth condyles, a lateral capitulum that articulates with the radius and a medial trochlea that articulates with the ulna

above the condyles on either side are epicondyles —> provide attachments for muscles and ligaments of the elbow

between epicondyle anteriorly is a depression, the coronoid fossa. receives process of the ulna (coronoid process) when the elbow bends

depression on the posterior surface, the olecranon fossa, receives a different ulnar process, the olecranon process, when the elbow straightens

radius

crosses over the ulna when the hand is turned so that the palm faces backward

thick, disclike head at the upper end of the radius articulates with the capiulum of the humerus and a notch of the ulna (radial notch) . allows radius to rotate

below the head on the radial shaft is radial tuberosity. attachment for biceps brachii

at distal end of radius, a lateral styloid process provides attachments for ligaments of the wrist

ulna

medial to the radius and longer than the radius

at the proximal end, ulna has a wrenchlike opening, the trochlear notch, that articulates with the trochlea of the humerus

olecranon and coronoid process above and below this notch provide attachment for muscles

at distal end, knoblike head articulates laterally with a notch of the radius (ulnar notch) + disc of fibrocartilage inferiorly

medial styloid process at the distal end of the ulna provides attachments for wrist ligaments

hand

made up of the wrist, palm, and fingers

8 carpal bones in two rows of four bones each. resulting compact mass is called a carpus

carpus articulates with the radius and the fibrocartilaginous disc on the ulnar side

distal side articulates with the metacarpal bones

five metacarpal bones

• cylindrical with rounded distal ends that form the knuckles of a clenched fist

phalanges are finger bones

• each finger has three phalanges - a proximal, middle, and a distal phalanx — except the thumb, which was two (no middle phalanx)

A - surgical neck; B - anatomical neck

on the lateral distal end of the humerus is the __, a round condyle that articulates with the radius

capitulum

A - greater tubercle
B - lesser tubercle

the ____ of the humerus is located just distal to the head while the ___ of the humerus is distal to the tubercles

anatomical neck; surgical neck

on the medial distal end of the humerus is the ___ , a condyle that articulates with the ulna

trochlea

A - head

B - radial tuberosity

C - styloid process

in the humerus, the narrowing between the head and the two tubercles is called the __ neck

anatomical

identify

radial tuberosity

A - olecranon process

B - trochlear notch

C - coronoid process

olecranon process

where is the head of the ulna located?

distal end of the bone