CLAVICLE

long, slender bone that lies horizontally across the root of the neck just beneath the skin

articulates with the:

sternum and 1st costal cartilage (medially)

with the acromion process of the scapula (laterally)

acts as a strut that holds the arm away from the trunk

transmits forces from the upper limb to the axial skeleton and provides attachment for muscles

the medial two thirds of the clavicle is convex forward and its lateral third is concave forward.

a flat triangular bone

lies on the posterior chest wall between the 2nd and 7th ribs.

On its posterior surface, the spine of the scapula projects backward.

The lateral end of the spine is free and forms the acromion

The inferior angle of the scapula can be palpated easily in the living subject and marks the level of the 7th rib and the spine of the 7th thoracic vertebra

Acromion

articulates with the clavicle

Glenoid Cavity or Fossa

pear-shaped

formed by superolateral angle of the scapula

articulates with the head of the humerus at the shoulder joint

Coracoid Process

projects upward and forward above the glenoid cavity

provides attachment for muscles and ligaments

Suprascapular Notch

medial to the base of the coracoid process

Subscapular Fossa

shallow

formed by the concave anterior surface of the scapula

Supraspinous Fossa (above) & Infraspinous Fossa (below)

divided by the spine at the posterior surface of the scapula

articulates with the scapula at the shoulder joint

articulates with the radius and ulna at the elbow joint

Head

upper end of the humerus

forms about one third of a sphere and articulates with the glenoid cavity of the scapula.

Lesser Tuberosities

immediately below the head

Bicipital Groove

separates the lesser tuberosities from each other

Surgical Neck

narrow

where the upper end of the humerus joins the shaft

Deltoid Tuberosity

about halfway down the lateral aspect of the shaft

a roughened elevation

Spiral Groove

behind and below the tuberosity

accommodates the radial nerve

Medial and Lateral Epicondyles

lower end of the humerus

for the attachment of muscles and ligaments

Capitulum

rounded

for articulation with the head of the radius

Trochlea

pulley-shaped

for articulation with the trochlear notch of the ulna

Radial Fossa

above the capitulum

receives the head of the radius when the elbow is flexed

Coronoid Fossa

above the trochlea anteriorly

receives the coronoid process of the ulna in elbow flexion

Olecranon Fossa

above the trochlea posteriorly

receives the olecranon process of the ulna when the elbow joint is extended