Shoulder Muscles

Question 1

Trapezius

Answer 1

Origin-Occipital bone, spines of C7 and all Thoracic vertebrae (T1-T12)

Insertion- Clavicle, Acromion and spine of scapula.

Action- Upper fibres=Elevate, and extend head
Middle fibres= Retract scapula
Lower fibres= Rotate scapula and stabilize

Question 2

Pectoralis Minor

Answer 2

Origin- 3rd to 5th rib

Insertion- Coracoid process

Action- Protraction and depression of scapula, elevates the ribs during forced inhalation

Question 3

Serratus Anterior (Boxers)

Answer 3

Origin- 1st - 8th/9th rib

Insertion- VertebrL (medial) border scapula

Action- Abducts and protracted scapula, elevates ribs when scapula is stabilised

Abduction and flexion (punch)

Question 4

Rhomboid major

Answer 4

Origin- T2 to T5

Insertion- vertebral (medial) border of scapula

Action- Elevatea and retracts scapula

Works with other muscles such as traps and levatof scapulae and stratus anterior

Question 5

Rhomboid minor

Answer 5

C7 and T1

Insertion- Vertebral (medial) border of scapula superior to spine

Action- Elevates and retracts scapula

Question 6

Levatof scapulae

Answer 6

Origin- Transverse process C1- C4

Insertion- Vertebral (medial) border of scapula superior to spine

Action Elevates and retracts scapula/ laterally flexes the neck

Question 7

Supraspinatous

Answer 7

Origin- Supraspinatous fossa

Insertion- Greater tubercle

Action- Abduct, stabilizes humerus

Tendon- sitting, hand behind back

Question 8

Infraspinatus

Answer 8

Origin- Infraspinatus fossa

Insertion- greater tubercle

Abducts- laterally rotates, abducts, extends and horizontally extends the shoulder

Question 9

Teres minor

Answer 9

Origin- superior half lateral border of scapula

Insertion- greater tubercle

Action- laterally rotates, abducts, extends, horizontally extends and stabilises the shoulder

Question 10

Subscapularis

Answer 10

Origin- Subscapular fossa

Insertion- lesser tubercle

Action- medially rotates shoulder and stabilises

Side lying, flexion, resist medial rotation

Question 11

Deltoid

Answer 11

Origin-lateral third clavicle, Acromion and spine scapula

Insertion- Deltoid tuberosity

Action- Anterior- flex, medially rotates And horizontally flexes shoulder

Posterior - extend, laterally rotates and horizontally extends and all abduct

Question 12

Teres major

Answer 12

Origin- lateral side of inferior angle and lower border

Insertion- lesser tubercle

Action- extends, abducts and medially rotates shoulder

Lye prone, abduction

Question 13

Pectoral is major

Answer 13

Origin- clavicle, sternum, costal cartilage of 2nd to 6th rib

Insertion- greater tubercle

Action- Abducts and medially rotates

Clavicular fibres - flexes arm, horizontally addicts shoulder

Sterno1 costal fibres- Extends flexes arm against resistance

Question 14

Latissimus dorsi

Answer 14

Origin- lower 6 thoracic, lower 3/4 ribs, thoracolumbar aponeurosis and posterior iliac crest

Insertion- lesser tubercle

Action- Extends, addicts shoulder and medially rotates shoulder

Supine- flexion