Deltoid vs Pectoralis major
| Property | Deltoid | Pectoralis major |
|---|---|---|
| Latin Name | Musculus deltoideus | Musculus pectoralis major |
| Type | Muscle | Muscle |
| Body System | Muscular | Muscular |
| Body Region | Shoulder | Thorax |
| Function | The primary abductor of the shoulder joint. The anterior fibers flex and medially rotate the arm. The posterior fibers extend and laterally rotate the arm. Gives the shoulder its rounded … | A powerful adductor, flexor, and medial rotator of the arm at the shoulder. Essential for pushing movements, climbing, and arm-swinging activities. |
| Clinical Significance | Deltoid paralysis from axillary nerve injury prevents arm abduction. The deltoid is a common site for intramuscular injections. Rotator cuff tears may cause compensatory deltoid overuse. | Pectoralis major rupture occurs during heavy bench pressing. Poland syndrome involves congenital absence of the pectoralis major. The muscle is used in pectoralis major flap reconstructive surgery. |
| FMA ID | 32521 | 9627 |