Shoulder Flashcards
Pectoralis major
O: clavicular head - medial half clavicle
Sternocostal head - anterior surface of sternum and costal cartilage of the first 6-7ribs
Abdominal head - integrate with external oblique muscles
I: lateral lip of intertubercular groove
F: flexion, adduction, medial rotation
Clavicular head: flex an extended arm
Sternocostal head: extend a flexed arm
Reverse function: expand chest for inhalation
I: medial and lateral pectoral nerves
Pectoralis minor
O: anterior surface of ribs 3-5
I: coracoid process
I: medial pectoral nerve
F: produces downward rotation and protraction
Subclavius
O: superior first rib and costal cartilage
I: subclavius groove
I: direct branch of brachial plexus
F: pulls tip of shoulder down, stabilizes sternoclavicular by pulling clavicle medially, posterior axial rotation (after 90 degrees of abduction and flexion)
Deltoid
O: spine of scap, lateral margin of acromion and lateral 1/3 clavicle
I: deltoid tuberosity
I: axillary nerve
F: prime mover abduction between 30-90 degrees
Supraspinatus
O: suprspinus fossa
I: greater tubercle superior aspect
I: suprascapular nerve
F: prime mover abduction first 15-30degrees
Infraspinatus
O: infraspinus fossa
I: posterior surface greater tubercle
I: suprascapular nerve
F: prime mover lateral rotation
Teres minor
O: lower 2/3 lateral border of scapular
I: posterior surface of greater tubercle
I: axillary nerve
F: lateral rotation and adduction
Teres major
O: posterior surface of inferior scap angle
I: medial lip intertubercular groove
I: lower subscapular nerve
F: medial rotation, and extension and some adduction
Subscapularis
O: Subscapular fossa
I: lesser tubercle
I: upper and lower subscapular nerve
F: prime mover medial rotation
Serratus anterior
O: lateral surface of upper 8-9 ribs
I: medial border of scap, most of them lower 1/3
I: long thoracic nerve
F: protraction and upward rotation, stabilizes scap by keeping scap attached to thoracic wall
Name of trunks and their roots
Upper trunk - C5 and C6
Middle Trunk - C7
Lower trunk - C8 and T1
Name the chords and their divisions
Lateral cord - anterior division from upper and middle trunk
Posterior - All 3 posterior divisions
Medial - anterior division from lower trunk
Location of trunk, division and cords
Trunk - posterior triangle
Divisions - behinds clavicle
Cords - within axial and relative to axillary artery (eg posterior cord in posterior to axillary artery)
Supraclavicular branches arise from ____ of brachial plexus and are positioned ____ relative to clavicle
Upper trunk or roots
Superior
Infraclavicular branches arise from ____ of brachial plexus and are positioned ____ relative to clavicle
Cords
Inferior
Supraclavicular branches
Dorsal scapular
Long thoracic
Nerve to subclavius
Suprascapular
Infraclavicular branches from lateral cord
Lateral pectoral N -
Musculocutaneus
Median N
Lateral root of median N
Infraclavicular branches of medial cord
Medial pectoral
Medial cutaneous nerve of arm
Intercostobrachial
Medial cutaneous nerve of forearm
Ulnar N
Medial root of median nerve
Posterior cord branches of Infraclavicular group
Upper subscapular
Thoracodorsal
Lower subscapular
Axillary
Radial
Dorsal scapular
Supraclavicular
Root of C5
Pure motor
Levator scap, rhomboids
Long thoracic N
Supraclavicular
C5-C7 roots
Pure motor to serratus anterior
Upper Subscapular
C5, C6
Posterior cord
pure motor to upper half of subscapula
Thoracodorsal
Segment C6-C8,
Posterior cord
pure motor to Lat
Lower subscapular N
C5-C6
Posterior cord
motor to lower 1/2 subscap and teres major