Myology Specific Muscles Flashcards
Trapezius
Divisions
Upper
Middle
Lower
Because their attachments and actions are different
Trapezius - three different parts
Upper fibers
A, O, I
A -
bilaterally: extend the head and neck
Unilaterally: elevate the scapula (scapulothoracic joint) & upwardly rotate the scapula (s/t) joint
O - superior nuchal line, EOP (external occipital protuberance) and nuchal ligament (axial)
I - lateral 1/3 clavicle (anterior surface/appendicular)
Named for its shape
Trapezius
Middle
O: Nuchal ligament at C6 spinal process (S.P.) C7 - T3
I: acromion process and spine of the scapula
A: retraction of the scapula (adduction)
Trapezius
Lower
O: S.P. of T4-T12
I: tubercle of the spine of the scapula
A: depression of the scapula (abduction)/ upward rotation of the scapula
Rhonboids
A, I, O
Minor
A-retraction of the scapula (adduction)
O-SP of C7 and T1
I-medial/vertebral border of the scapula level with the root spine of the scapula
Named for geometric shape
Rhomboid major
A, I, O
A- retraction of the scapula (adduction)
O- SP of T2 to T5
I-medial/vertebral border of the scapula between the spine and the inferior angle
Named for geometric shape
levator scapula
A, I, O
A- elevate the scapula
O- TRanverse process of C1-4
I - superior angle of the scapula
Splenius cervicis
A, I, O
O - SP of T3-T6
I - TP OF C1-C3
A - unilaterally ipsilateral flexion and ipsilateral rotation head and neck
Bilaterally - extend/hyperextended the neck HYPEREXTENSION
Splenius - bandage ,
Splenius capitis
A, I, O
A- bilateral: extension of head and neck
Unilateral : ipsilateral rotation and lateral flexion
O - lower portion of the nuchal ligament and spinous process of C7-T3
I - mastoid process of the superior nuchal line (lateral) of occipital bone
Second layer of posterior cervical muscles
Sternocleidomastoid
SCM
A, I, O
Named for it’s attachment. Sterno- sternum Clavicular- clavical mastoid - mastoid process
I: mastoid process of the temporal bone and lateral portion of the superior nuchal line of occiput
O: sternal head: top of the manubrium
Clavicular head: medial one third of the clavicle
Unilaterally: contralateral rotation of the head, ipsilateral flexion of the head/neck
Bilaterally: flexion of the neck, extension of the head
anterior deltoid
A, O, I
O - lateral 1/3 of clavicle
A- all fibers: abduct the shoulder joint
Anterior: flex the humerus, medially rotate the shoulder joint, horizontally adduct the shoulder joint
I- deltoid tuberosity
middle deltoid
A, O, I
O - acromion
I- deltoid tuberosity
A- all fibers: abduct the shoulder joint
Posterior deltoid
A, O, I
O - spine of the scapula
I - deltoid tuberosity
A - all fibers: abduct the shoulder joint
Posterior: extend the humerus, laterally rotate the shoulder joint, horizontally abduct the shoulder joint
Triceps brachii
A, I, O
A - extends the elbow
O - long head - infraglenoid tubercle;
lateral head - posterior proximal 1/2 humerus lateral to radial/spiral groove;
medial head - posterior distal 1/2 humerus medial to radial/spiral groove
I - olecranon process of ulna for all three heads
Named for three heads, arm
Extensior carpi radialis longus
A, I, O
Origin - distal 1/3 lateral supracondylar ridge (humerus) and lateral epicondyle via common extensor tendon
I - base 2nd metacarpal
A - extension and radial deviation of wrist
Extensor carpi radialis brevis
A, I, O
O - Lateral epicondyle via common extensor tendon
I - base of 3rd metacarpal
A - extension and radial deviation of wrist
Extensor carpi ulnaris
A, I, O
I- base of 5th metacarpal and hamate
O. - lateral epicondyle of humerus via the common extensor tendon and proximal posterior boarder ulna
A. - wrist extension and ulnar deviation or adduction of the wrist (combined action)
Named for location and action
Flexor carpi radialis
A, O, I
Named for action and location
A: flexion of wrist and Abduction of wrist (towards radius)
I: base of 2nd and 3rd metacarpal
O: medial epicondyle of humerus via the flexor tendon
Palaris longus
A, I, O
O - medial epicondyle via the flexor tendon
I - palmar aponeurosis
A - flexion of wrist
- not present in everyone
- *only tendon not under flexor retinaculum
Flexor carpi ulnaris
A, I, O
I- base of 5th metacarpal, hamate, and pisiform
O- medial epicondyle of humerus via the flexor tendon (humeral head); olecranon process ulna (ulnar head)
A - wrist flexion and ulnar deviation or adduction of the wrist (combined action)
Named for location and action