7 橈動脈經過解剖學鼻煙盒（anatomical snuff box）後，穿過下列何者進入手掌？

對掌拇肌（opponens pollicis） 第一掌側骨間肌（lst. palmar interosseous m.）

第一背側骨間肌（lst. dorsal interosseous m.） 外展拇短肌（abductor pollicis brevis）

ANS 第一背側骨間肌（lst. dorsal interosseous m.

The anatomical snuffbox, or radial fossa, (in Latin Foveola radialis), is a triangular deepening on the radial,dorsal aspect of the hand—at the level of the carpal bones, specifically, the scaphoid and trapezium bones forming the floor. The name originates from the use of this surface for placing and then sniffing powderedtobacco, or “snuff.”