Muscle of Shoulder Flashcards
Trapezius
Attachments:
Superior nuchal line
• External occipital protuberance
• Ligamentum nuchae
• Spinus process of CV7 to TV12
• Lateral 1/3 of clavicle
• Acromion
• Spine of scapula
Action:
elevation, retraction, depression, adduction, and upward rotation of scapula
Innervation: Spinal accessory nerve 11
Blood supply: Superior branch of transverse cervical artery
Rhomboid Major
Attachments:
- Spinous process of TV2 to TV5
- Medial border of scapula between spine and inferior angle
Action: Retracts scapula
Innervation: Dorsal scapular nerve (C4, C5)
Blood supply:Deep branch of transverse cervical artery (aka dorsal scapular artery)
Rhomboid Minor
Attachments:
- Lower portion of ligamentum nuchae, spinal processes of CV7 and T1
- Medial border of scapula at the spine of scapula
Action: Retracts scapula
Innervation:Dorsal scapular nerve (C4, C5)
Blood supply:Deep branch of transverse cervical artery (aka dorsal scapular artery)
Levator Scapulae
Attachments: Transverse processes of CV1-CV4
Posterior surface of medial border of scapula from superior angle to spine of the scapula
Action: elevates scapula
Innervation: Dorsal scapular N. (C5) and anterior rami of C3 and C4
Blood supply: Transverse cervical artery, dorsal scapular artery
Latissimus Dorsi
Attachments: spinous process of TV7-TV12 vertebrae and related interspinous ligaments, thoracolumbar fascia, spinous process of LV4 or LV5, iliac crest, lower 3 or 4 ribs, inferior angle of scapula, intertubercular groove of the humerus
Action: adduction, medial rotation and extension of arm at glenoid humeral joint
Innervation: Thoracodorsal nerve (C6, C7, C8)
Blood supply: Thoracodorsal artery
Teres Major
Attachments: Posterior surface of inferior angle of scapula, medial lip of intertubercular groove on anterior surface of humerus
Action: medial rotation and extension of arm at glenoid humeral joint
Innervation: Inferior subscapular nerve (C5, C6, C7)
Blood supply: Subscapular and circumflex scapular arteries, posterior humeral circumflex artery
Deltiodeus
Attachments: Inferior edge of spine of scapular, lateral margin of acromion, anterior border of 1/3 of clavicle
Action: Major abductor of arm, clavicular fibers assist in flexing arm, posterior fibers assist in extending arm
Innervation: axillary nerve
Blood supply: acromial branch of thoracoacromial artery (trunk), anterior and posterior humeral circumflex artery
Serratus Anterior
Attachments: lateral surfaces of upper 8-9 ribs and deep fascia overlying related intercostal spaces, costal surface of medial border of scapula
Action: protraction and rotation of scapula, stabilizes scapula, accessory breathing muscle when pectoral girdle locked
Innervation: Long thoracic nerve
Blood supply: lateral thoracic artery
Pectoralis Major
Attachments: Clavicular head, sternum, first 7 costal cartilages, sternal end of 6th rib, intertubercular groove of humerus
Action: flexion, adduction, and medial rotation of humerus (arm) at glenohumeral joint; flexion of extended arm at clavicular head; extension of flexed arm at sternocostal head, accessory breathing muscle
Innervation: medial and lateral pectoral nerves (C5 to T1)
Blood supply: pectoral branch of the thoracoacromial trunk
Pectoralis Minor
Attachments: ribs 3 to 5 and deep fascia overlying the related intercostal spaces, coracoid process of scapula
Action: pulls tip of shoulder down, protracts scapula, accessory breathing muscle
Innervation: medial pectoral nerve
Blood supply: pectoral branch of the thoracoacromial trunk
Subclavius
Attachments: first rib and groove on inferior surface of middle 1/3 of clavicle
Action: pulls tip of shoulder down, pulls clavicle medially to stabilize sternoclavicular joint
Innervation: Nerve to subclavius (C5, C6)
Blood supply: thoracoacromial trunk, clavicular branch
