The Shoulder Complex Muscles of the AC Joint

The Shoulder Complex

Muscles of the AC Joint Chapter 4

Movements of the Scapula 1. Elevation 2. Depression 3. Adduction (retraction) 4. Abduction (protraction) 5. Downward rotation 6. Upward rotation

Anterior Muscles § Pectoralis Minor § Serratus Anterior

Pectoralis Minor § Origin: Anterior surface of 3, 4, and 5 ribs § Insertion: Coracoid process § Actions: § AC Abduction § Downward rotation § Depression

Serratus Anterior § Origin: Lateral surface of upper 8 ribs § Insertion: Anterior surface of medial border and inferior angle of scapula. § Actions: § AC Abduction § Upward Rotation

Posterior Muscles § Levator Scapluae § Trapezius § Rhomboid

Levator Scapulae § Origin: Transverse processes of the first 4 cervical vertebrae. § Insertion: Superior angle and medial border of the scapula. § Actions: Elevation

Trapezius § Origin: Occipital bone, ligamentum nuchae, spinous process of the C 7 and all Thorasic vertebrae § Insertion: § 1. Lateral 1/3 of clavicle. § 2. Top of Acromion process. § 3. Upper border of spine of the scapula. § 4. Medial surface of spine of the scapula. § Actions: § Upper – elevation of the scapula § Middle – elevation, upward rotation, & AC adduction § Lower – depression, AC adduction and upward rotation

n Upper – elevation n Middle – elevation, upward rotation, & adduction n Lower – depression, adduction and upward rotation

Pull of the lower fibers Movement of scapula

Rhomboid (major and minor) § Origin: Ligamentum nuchea and spinous process of C 1 -7 and 2 -5 T § Insertion: Medial border of the scapula § Actions: § AC Adduction § Downward rotation, § Elevation

Subclavius § Origin: Superior aspect of first rib § Insertion: Inferior aspect at mid-clavicle § Action § Depression § Stabilization

Muscles of the Shoulder Joint Chapter 5

Anterior Shoulder (GH Joint) Muscles § Coracobrachialis § Pectoralis Major § Subscapularis

Coracobrachialis § O: Coracoid process § I: Anteromedial surface of midshaft of humerus § Actions: § Flexion § Adduction of the shoulder § Horizontal Adduction

Pectoralis Major § Origin: § Medial two-thirds of clavicle § Sternum § Insertion: intertubercular groove § Actions § Upper fibers (Clavicular) § Internal rotation § Horizontal Adduction § Flexion § GH Adduction § [Abduction w/ Arm above 90 degrees] § Lower fibers (Sternal) § Internal Rotation § Horizontal adduction § Extension § GH Adduction

Subscapularis § O: Subscapular fossa § I: Lesser tubercle and crest of humerus § Actions: § § § Internal Rotation GH Adduction Extension from flexed position § Stabilization § Anterior Rotator Cuff Muscle.

Superior Shoulder Muscles § Deltoid § Supraspinatus

Deltoid § Origin § Lateral 1/3 of clavicle (Anterior fibers) § Acromion process (Middle fibers) § Spine of scapula (Posterior fibers) Insertion – deltoid tuberosity § § Actions § Anterior – GH Abduction, Flexion, Horizontal adduction, & Internal rotation. § Middle – GH Abduction § Posterior – GH Abduction, Extension, Horizontal abduction, & External rotation

Supraspinatus § O: Supraspinous fossa § I: Greater tubercle § Action: § GH Abduction § Stabilization § Superior Rotator Cuff Muscle.

Inferior Shoulder Muscles § Latissimus Dorsi § Teres Major

Latissimus Dorsi § O: Spinous process of lower 6 thorasic and all lumbar and sacral vertebrae; iliac crest § I: Intertubercular groove § Actions: § Extension § GH Adduction § Horizontal Abduction

Teres Major § O: Inferior angle of scapula § I: Intertubercular groove § Actions: § Extension § GH Adduction § Internal rotation § “Lats little helper”

Posterior Shoulder Muscles § Infraspinatus § Teres Minor

Infraspinatus § O: Infraspinous fossa § I: Greater tubercle § Actions: § External rotation § Horizontal abduction § Extension § Stabilization § Posterior Rotator Cuff Muscle

Teres Minor § O: Upper 2/3 of lateral § § border of scapula I: Greater tubercle Actions: § § External rotation Horizontal abduction Extension Stabilization § Posterior Rotator Cuff Muscle

Practice § Name the actions of the § § § scapula (AC joint) Elevation Depression Adduction (retraction) Abduction (protraction) Upward rotation an Downward rotation. § Name the actions of the § § § § shoulder (GH) joint. Flexion Extension Adduction Abduction Horizontal adduction Horizontal abduction Medial rotation Lateral rotation.

Scapula Adduction Abduction Upward Rotation Trap Pect Minor Serratus (middle) Ant. Trap Serratus Trap (lower) Ant. (middle) Rhomboids Trap (lower) Downward Rotation Pect Minor Rhomboid

Practice § Name the muscles for § § Horizontal Adduction Pect Major (upper) Pect Major (lower) Corachobrachialis Deltoid (anterior) § § Horizontal Abduction Deltoid (post) Infraspinatus Teres minor Lats

Practice § List the muscles the do flexion of the shoulder § List the muscles the do AC adduction

Name the muscle. Coracobrachialis Name the action Adduction of the shoulder

Name the muscle. Pectoralis Major

Name the muscle. Rhomboid Name the action Adduction of scapula

Name the muscle. Pectoralis minor Name the action Depression of the scapula

Name the muscle. Subscapularis Name the action Internal rotation of the shoulder

Name the muscle. Trapezius Name the action Adduction of the scapula Name the action Upward rotation

Name the muscle. Levator scapula Name the action Elevation of the scapula

Name the muscle. Deltoid Name the action Abduction of shoulder

Name the muscle. Infraspinatus Name the action External rotation

Name the muscle. Name the action Teres Major Adduction of scapula

Name the muscle. Serratus Anterior Name the action Abduction of scapula

Name the muscle. Teres Minor Name the action if the humerus move directly to the posterior Extension of the shoulder

Name the muscle. Supraspinatus Name the action Abduction of the shoulder

? Latissimus Dorsi

Coracobrachialis Subscapularis Pect. Major Deltoid

Supraspinatus Teres Major Infraspinatus Teres Minor

Pectoralis Minor Levator Scapula Rhomboid

? § Origin: Occipital bone, ligamentum nuchae, spinous process of the C 7 and all Thorasic v. § Insertion: § § 1. Lateral 1/3 of clavicle. 2. Top of Acromion process. 3. Upper border of spine of the scapula. 4. Medial surface of spine of the scapula. § Actions: § Upper – elevation § Middle – retraction and upward rotation § Lower – depression and upward rotation

? § Origin: Supraspinatus fossa § Insertion: Greater tubercle of the humerus § Action: Weak abduction; stabilization § Name another muscle that abducts the shoulder.

? § Origin: Medial 2/3 of the clavicle; medial portion of the first 6 ribs & the adjoining sternum. § Insertion: Outer lip of the intertubercular groove.

? § Origin: 1) posterior crest of the iliac crest, 2) back of the sacrum and spinous processes of the lumbar and the lower 6 thorasic vertebrae and 3) inferior angle in some § Insertion: Intertubercle groove § Name a muscle that would have the same actions as this one.

? § Origin: Ligamentum nuchea and spinous process of C 1 -7 and 2 -5 T § Insertion: Medial border of the scapula § Actions: Downward rotation, retraction, and elevation

? § Origin: Lateral surface of upper 8 ribs § Insertion: Anterior surface of medial border and inferior angle of scapula. § Actions: Protraction (upper) and Upward Rotation (upper and lower)

? § Origin: lateral 1/3 of clavicle, border of Acromion, lower edge of the spine of the scapula § Insertion: deltoid tuberosity on the lateral side of the humerus § Actions § Anterior – Flexion, medial rotation and abduction § Middle – Abduction § Posterior – Extension, lateral rotation and abduction

? § Origin: Transverse processes of the first 4 cervical vertebrae. § Insertion: Superior angle and medial border of the scapula. § Action: Elevation