SERRATUS ANTERIOR
| ORIGIN Upper eight ribs and anterior intercostal membranes from midclavicular line. Lower four interdigitating with external oblique |
 |
| INSERTION Inner medial border scapula. 1 and 2: upper angle; 3 and 4: length of costal surface ; 5-8: inferior angle |
|
| ACTION Laterally rotates and protracts scapula |
|
| NERVE Long thoracic nerve (C5, 6, 7) (from roots) slips from ribs 1 and 2: C5; 3 and 4: C6; 5-8: C7) |