Which bone is labeled D on a wrist radiograph?

Which bone is labeled D on a wrist radiograph?

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

Answer: (A)

In the wrist, the proximal row of carpal bones runs from the thumb side to the little finger as scaphoid, lunate, triquetrum, and pisiform. The bone labeled D is the small, rounded bone on the ulnar side that sits on top of the triquetrum—the pisiform. It’s a sesamoid bone within the tendon of flexor carpi ulnaris, which is why it appears as a distinct round projection on standard wrist radiographs.

In the wrist, the proximal row of carpal bones runs from the thumb side to the little finger as scaphoid, lunate, triquetrum, and pisiform. The bone labeled D is the small, rounded bone on the ulnar side that sits on top of the triquetrum—the pisiform. It’s a sesamoid bone within the tendon of flexor carpi ulnaris, which is why it appears as a distinct round projection on standard wrist radiographs.