Which carpal bone sits on top of the Triquetrum?

Which carpal bone sits on top of the Triquetrum?

• A. Pisiform
• B. Lunate
• C. Scaphoid
• D. Hamate

Answer: (A)

The important idea here is how the carpal bones relate to each other in the proximal row. The triquetrum is a small triangular bone on the ulnar side of that row. The pisiform is a tiny sesamoid bone embedded in the tendon of the flexor carpi ulnaris and sits on the front (palmar) surface of the triquetrum, effectively resting on top of it. This position is why the pisiform is the bone described as sitting on top of the triquetrum. The other bones—lunate and scaphoid are adjacent in the proximal row but do not sit on the top of the triquetrum, and the hamate is in the distal row toward the pinky side.

The important idea here is how the carpal bones relate to each other in the proximal row. The triquetrum is a small triangular bone on the ulnar side of that row. The pisiform is a tiny sesamoid bone embedded in the tendon of the flexor carpi ulnaris and sits on the front (palmar) surface of the triquetrum, effectively resting on top of it. This position is why the pisiform is the bone described as sitting on top of the triquetrum. The other bones—lunate and scaphoid are adjacent in the proximal row but do not sit on the top of the triquetrum, and the hamate is in the distal row toward the pinky side.