Which carpal bone forms the floor of the anatomical snuff box?

Which carpal bone forms the floor of the anatomical snuff box?

• A. Lunate
• B. Capitate
• C. Trapezium
• D. Scaphoid

Answer: (D)

The floor of the anatomical snuff box is formed primarily by the scaphoid bone, a prominent proximal carpal bone lying directly beneath that hollow. The trapezium can contribute to the floor on the radial side as well, but the scaphoid is the main structure seen deep to the snuff box. This is why tenderness over the snuff box strongly suggests a scaphoid fracture, since that bone lies right under the area best palpated when the thumb is extended.

The floor of the anatomical snuff box is formed primarily by the scaphoid bone, a prominent proximal carpal bone lying directly beneath that hollow. The trapezium can contribute to the floor on the radial side as well, but the scaphoid is the main structure seen deep to the snuff box. This is why tenderness over the snuff box strongly suggests a scaphoid fracture, since that bone lies right under the area best palpated when the thumb is extended.