| Muscle of upper torso |
Origin |
Insertion |
Action |
| Deltoid - anterior - lateral - posterior | clavicle and scapula | humerus | shoulder abduction - flexion - extension & rotation |
| Pectoralis major | clavicle, sternum and ribs | humerus | shoulder adduction (horizontal) |
| rhomboids major & minor (back between shoulder blades) | cervical and thoracic vertebrae | scapula | shoulder girdle retraction (squeeze shoulder blades together) |
| trapezius upper | base of skull and cervical vertebrae | clavicle and scapula | lateral flexion of the neck roation of the neck adduction of scapula rotation of scapula |
| trapezius middle | thoracic vertebrae | scapula | adducts scapula elevates scapula |
| trapezius lower | thoracic vertebrae | scapula | depresses scapula |
| supra.spinatus (rotator cuff) | scapula | humerus | assist deltoid in shoulder abduction |
| infran.spinatus (rotator cuff) | scapula | humerus | laterally rotates & adducts shoulder |
| teres major & minor (beneath rhomboids) | scapula | humerus | shoulder extension & adduction |
| pectoralis minor (front chest) | ribs | scapula | depresses scapula elevates ribs 3-5 during forced inspiration |
