Muscle Name: serratus anterior

AKA:  

Abbreviation:  

Spinal Nerve Roots:
    C5
    C6
    C7

Brachial Plexus Trunks: NA

Brachial Plexus Cords:  NA

Named Nerves:    long thoracic nerve

Proximal Attachment:   Surface of the upper 8 ribs.

Distal Attachment:   Costal aspects of the medial margin of the scapula.

Action:    Protracts the scapula against the thoracic wall.

Needle Insertion:   With the patient lying on their side the needle is inserted into the muscle over the 6th rib located on the midaxillary line.

Activation for EMG:   The patient is asked to push their hand agains the wall.

Pitfalls:  Be aware of the risk of pneumothorax.

Notes: A lesion of the long thoracic nerve will lead to weakness of the serratus anterior and posterior winging of the scapula when the patient is asked to push against a wall.