The serratus anterior originates from which ribs?

• A. External surfaces of the 8th and 9th ribs
• B. First through second ribs
• C. Third through fourth ribs
• D. Tenth through eleventh ribs

Answer: (A)

Serratus anterior attaches to the external surfaces of the ribs along the lateral chest wall, with origin on the upper portion of the rib cage. The broad, fan-shaped fibers originate from several ribs and then sweep to the medial border of the scapula. In many exam contexts this broad origin is summarized as coming from the upper ribs, and among the given options the one listing the 8th and 9th ribs best reflects this general region of attachment. The other options point to rib levels that are too high or too low to represent the typical origin span. Knowing this, remember that the serratus anterior’s role is to protract the scapula and hold it against the thoracic wall, with innervation by the long thoracic nerve.