3Pectoral GirdleAttach the bones of the upper limbs to the axial skeletonConsist of two bones: clavicle and scapulaThe joints are freely movable in many directions
4Clavicle Also known as the collarbone Long, slender S-shaped bone that is horizontally above the first ribTransmits mechanical force from the upper limb to the trunk
5Scapula Also known as the shoulder blade Large, flat triangular bone situated in the posterior part of the thorax
6A sharp ridge, the spine, runs diagonally across the back portion of the scapula body The lateral end of the spine is the acromion, where the scapula articulates with the clavicle
7The glenoid cavity is a depression inferior to the acromion The glenoid cavity is a depression inferior to the acromion. It articulates with the humerus head to form the shoulder joint.The coracoid process is where muscles attach.
9Upper Limb Consists of 30 bones (all paired up) Humerus in the arm Ulna and radius in the forearm8 carpals, 5 metacarpals, and 14 phalanges in the hand
10Humerus Longest and largest bone of the upper limb Articulates with the scapula at the shoulder and both the ulna and radius at the elbow
11Ulna Located on the medial side of the forearm (pinky side) Longer than the radius
12RadiusLocated on the lateral side of the forearm (thumb side)
13Humerus Bone Surface Markings Proximal end consists of a head that articulates with the scapula’s glenoid cavity and an anatomical neck where the epiphyseal plate used to be
14The body contains the deltoid tuberosity, a roughened V-shaped area where the deltoid muscle attaches
15At the distal end, the capitulum articulates with the head of the radius. The radial fossa is a depression that receives the head of the radius when the forearm is bent.
16The trochlea is a spool-shaped surface that articulates with the ulna. The coronoid fossa receives part of the ulna when the forearm is bent.The olecranon fossa is a depression on the back of the bone that receives the ulna when the forearm is straightened.
17Ulna Bone Surface Markings The olecranon forms the prominence of the elbow on the proximal end.The coronoid process along with the olecranon receives the trochlea of the humerus in the trochlear notch.
18The radial notch is a depression for the head of the radius. A styloid process is at the distal end.
19Radius Bone Surface Markings Disc-shaped head at the proximal end articulates with the capitulum of the humerus and radial notch of the ulnaRadial tuberosity is a raised, roughened area that is where the biceps brachii muscle attaches to the bone
20The distal end of the radius articulates with three carpal bones There’s a styloid process at the distal end (similar to the ulna)
21Carpus (Wrist) 8 carpals Held together by ligaments with four bones in each rowNamed for their shapesShort bones
22The carpals in the top row are the: Scaphoid, Lunate, Triquetrum, and PisiformThe carpals in the bottom row are the:Trapezium, Trapezoid, Capitate, and Hamate
23Metacarpus (Palm) 5 metacarpals Each consists of a proximal base, an intermediate body, and a distal headNumbered I-V starting with the thumbLong bones
24Phalanges (Fingers) 14 in each hand Thumb has two (proximal and distal)In each of the other four digits, there are three (proximal, middle, and distal)
32Checkpoint QuestionsWhich bones make up a pectoral girdle? What is the function of the pectoral girdle?With which part of the scapula does the humerus articulate?What part of the ulna is called the “elbow”?What part of which bones are commonly called the “knuckles”?What bones form the upper limb, from proximal to distal?