PHYT 622 CLINICAL GROSS ANATOMY MYOLOGY Muscles Anatomical Study of Guidelines for the study of muscle 1 name the muscle 2 find a description of its origin this usually will be a location on a bone bones or fascia 3 locate the origin on a skeleton articulated or loose bones 4 palpate the origin when possible on yourself and a partner 5 repeat steps 1 4 for the insertion 6 determine the action of the muscle by palpation and contraction of the muscle on yourself and a partner 7 check the action in a source book 8 note the nerve supply both from the peripheral nerve and root level perspective The Muscles 1 Trapezius superior fibers O 1 external occipital protuberance 2 medial 1 3 of the superior nuchal line of occiput 3 upper aspect of ligamentum nuchae I posterior border of lateral 1 3 of the clavicle A elevation and upper rotation of the scapula N accessory nerve CN XI and branches of C3 C4 Trapezius middle fibers O 1 inferior aspect of ligamentum nuchae 2 spinous proces of 7th cervical and upper thoracic I 1 medial margin of acromion process of scapula 2 superior lip of posterior border of spine of scapula A adduction of scapula N CN XI and C3 C4 Trapezius inferior fibers O spinous process of inferior thoracic vertebrae I medial end of the spine of scapula A depress uprward rotation of the scapula N CN XI and C3 C4 2 Rhomboideus Major and Minor 21 O Minor nuchal ligament and spinous processes of C7 T1 Major spinous processes of T2 T5 I Medial border of scapula from level of spine to inferior angle A Retract scapula rotates it to depress glenoid cavity and fixes scapula to thoracic wall N dorsal scapular nerve C4 C5 3 Levator Scapulae O transverse processes of C1 C4 I Superior part of medial border of scapula A Elevates scapula and tilts its glenoid cavity inferiorly by rotating the scapula N Branches directly from anterior rami of spinal nerves C3 and C4 and by branches C5 from the dorsal scapular nerve 4 Latissimus Dorsi O Spinous processes of T7 T12 thoracolumbar fascia iliac crest and last three or four ribs I Intertubercular groove of humerus A Extends adducts and medially rotates humerus at shoulder N thoracodorsal nerve C6 C7 C8 5 Teres Major O Dorsal surface of inferior angle of scapula I Medial lip of intertubercular groove of the humerus A Adducts arm and medially rotates shoulder N lower subscapular nerve C5 C7 6 Deltoid posterior fibers O posterior border of the spine of the scapula I deltoid tubercle of the humerus A extension horizontal abduction external rotation humerus N axillary C5 C6 Deltoid middle fibers 22 O superior surface of the acromion I deltoid tubercle A abduction of humerus N axillary C5 C6 Deltoid anterior fibers O lateral 1 3 of clavicle I deltoid tubercle A flexion horizontal adduction internal rotation humerus N axillary C5 C6 7 Pectoralis major O medial half of clavicle sternum superior six costal cartilage apponeurosis of external abdominal oblique I lateral lip of the intertubercular groove of humerus A flexes adducts and medially rotates arm at shoulder N medial and lateral pectoral nerves C5 C6 C7 C8 T1 8 Pectoralis minor O third to fifth ribs I coracoid process of scapula A depresses scapula and stabilize it N medial pectoral C6 C7 C8 9 Subclavius O junction of first rib and costal cartilage I inferior surface of clavicle A depresses clavicle N nerve to subclavius C5 C6 10 Serratus anterior O upper eight ribs 23 I medial border of scapula A rotates scapula upwards and pulls it anterior toward thoracic wall N long thoracic C5 C6 C7 11 Coracobrachialis O tip of the coracoid process of scapula I middle third of medial surface of humerus A help to flex and adduct arm at shoulder N musculocutaneus nerve C5 C6 C7 12 Supraspinatus O supraspinatus fossa of scapula I superior facet on greater tubercle of humerus A helps deltoid abduct arm at shoulder and acts with rotator cuff muscles N suprascapular nerve C5 C6 13 Infraspinatus O infraspinatus fossa of scapula I middle facet on greater tubercle of humerus A laterally rotates arm at shoulder and acts with rotator cuff muscles N suprascapular nerve C5 C6 14 Teres Minor O lateral border of scapula I inferior facet on greater tubercle of humerus A laterally rotates arm at shoulder helps to hold head in glenoid cavity N axillary nerve C5 C6 15 Subscapularis O sub scapular fossa of scapula I lesser tubercle of the humerus A medially rotates arm at shoulder and adducts it help to hold humeral head in glenoid cavity N upper and lower subscapular nerve C5 C6 C7 24 16 Biceps brachii O short head apex of coracoid process of scapula long head supraglenoid tubercle of scapula I tuberosity of radius and fascia of the forearm via bicipital apponeurosis A Supinates flexed forearm flexes forearm at elbow N musculocutaneous nerve C5 C6 17 Brachialis O distal half of anterior humerus I coronoid process and tuberosity of ulna A flexes forearm at elbow in all positions N musculocutaneous C5 C6 small contribution by the radial nerve C7 to lateral part of muscle 18 Triceps brachii O 1 long head infraglenoid tubercle of scapula 2 lateral head posterior surface of the humerus 3 medial head posterior surface of humerus inferior to radial groove I proximal end of olecranon of ulna and fascia of forearm A extends forearm at elbow is chief extensor of elbow steadies head of abducted humerus long head N radial nerve C6 C7 C8 19 Anconeus O lateral epicondyle of humerus I lateral surface of olecranon and superior part of posterior surface of ulna A assists triceps in extending elbow abducts ulna during pronation N radial nerve C6 C7 C8 20 Pronator Teres O medial epicondyle of humerus and coronoid process of ulna I middle of lateral surface of the radius 25 A pronates forearm and flex elbow N median nerve C6 C7 21 Flexor carpi radialis O medial epicondyle of humerus I base of 2nd metacarpal bone A flexes hand at wrist and abducts it N median C6 C7 22 Flexor carpi ulnaris O humeral head medial epicondyle of humerus ulnar head olecranon and posterior border of ulna I 1 pisiform bone 2 hook of hamate bone and of 5th metacarpal bone A flexes hand at wrist and adducts it N ulnar nerve C7 C8 T1 23 Palmaris Longus O medial epicondyle of humerus I distal half of flexor retinaculum and palmar aponeurosis A flexes hand at wrist and tightens palmar aponeurosis N median nerve C7 C8 24 Flexor digitorum superficialis O Humeroulnar head medial epicondyle of humerus ulnar collateral ligament and coronoid process of ulna Rradial head superior half