osteology

clavicle

Plan

· medial 2/3

· rounded in section

· convex forward to clear NV bundle

· lateral 1/3

· flat

· curves back to meet scapula

Sternal end

· facet for disc of SC jt

· attached along upper and posterior margin

· articular surface

· covered with fibrocartilage

· extends to undersurface for 1st costal cartilage

· capsule and synovial membrane attach to margin

Posterior surface

· origin of sternohyoid

· extends in line from SC jt

· neurovascular bundle more lateral

· subclavian vein medially

· cords of brachial plexus laterally

· trapezius takes origin from lateral 1/3

Acromial end

· facet for AC jt

Anterior surface

· deltoid takes origin from lateral 1/3

· may leave deltoid tubercle

· pectoralis major takes origin from medial 1/2

Upper surface

· clavicular head of sternomastoid takes origin from medial 1/3

Under surface

· plateau for attachment of costoclavicular ligament medially

· just lateral to sternal end

· groove for subclavius in middle

· from costoclavicular pit to conoid tubercle

· conoid tubercle at posterior part of flattened 1/3

· trapezoid ridge extends forward from conoid tubercle

scapula

Plan

· triangular blade

· lateral angle thickened as glenoid

· projected upwards as coracoid

· triangular spine from dorsal surface

· projected forward as acromion

Costal surface

· concave

· 3 or 4 ridges from vertebral edge to lateral angle

· attach fibrous septae for subscapularis

· subscapularis attached to

· costal surface

· lateral border to infraglenoid tubercle along ridge

· lateral angle bare

· separated from subscapularis by bursa

· serratus anterior attached to medial margin of costal surface

· upper 2 digitations - superior angle to base of spine

· next 2 digitations - base of spine to inferior angle

· last 4 digitations - costal surface on inferior angle

Upper border

· extends to base of coracoid

· dips into scapular notch

· transmits suprascapular nerve

· bridged by transverse scapular ligament

· ligament gives rise to inferior belly of omohyoid

Medial border

· gives rise to

· levator scapulae - upper angle

· rhomboid minor - down to base of spine

· rhomboid major - down to inferior angle via fibrous arch

Lateral border

· extends from glenoid fossa to inferior angle

· long head of triceps attached to infraglenoid tubercle

· roughened area below glenoid fossa

· ridge extends from infraglenoid tubercle to inferior angle

· teres major attaches to oval area at inferior angle below ridge

· teres minor attaches to elongated area below ridge more laterally

· origin may be bisected by groove for circumflex scapular vessels

· fascia over infraspinatus and teres minor attached to ridge

Spine

· projects back from dorsal surface of blade

· projects forwards as acromion

· rectangular

· carries facet for AC jt

· suprascapular vessels and nerve pass between glenoid and lateral edge of spine

· trapezius attaches to medial border of acromion and upper edge of spine

· on 5 mm wide bevelled surface

· ends at deltoid tubercle

· tubercle is lip on inferior margin of spine 3 mm from medial end

· deltoid tubercle attaches

· along inferior spine from deltoid tubercle laterally

· posterior, lateral and anterior borders of acromion to AC jt

· continues across joint to lateral clavicle

· acromion shows 4 ridges on lateral border for fibrous septae of deltoid

· coracoacromial ligament attaches to anterior margin of acromion

Lateral angle

· upper part of neck projected as coracoid process

· broadens from neck to margins of glenoid fossa

· pear-shaped

· faces forwards

· long head of biceps attaches to supraglenoid tubercle

· long head of triceps attaches to infraglenoid tubercle

· capsule attaches to labrum and surrounding bone

Coracoid process

· curves forwards and laterally from base

· 4 ligaments and 3 muscles

· conoid ligament attached to knucle

· trapezoid ligament attached to ridge that runs towards tip

· coracoacromial ligament attached to posterior edge

· coracohumeral ligament attached to inferior surface

· pectoralis minor attached to anterior surface

· short head of biceps attached to lateral facet of tip

· coracobrachialis attached to medial facet of tip