There are 8 carpal bones that make up the wrist. The bones are arranged in two rows: the proximal bones articulate with the distal ends of the radius and ulna (except for the pisiform, which articulates only with the triquetrum and attaches to the ligaments of a few muscles of the hand and arm); the distal bones articulate with the proximal ends of the metacarpal bones.

Proximal row: The scaphoid gets its name from its boat-like shape. It's on the radial side of the wrist. Immediately medial to the scaphoid is the lunate bone (previously known as the "semilunar" bone because its concave shape resembles a half moon; the modern term means "crescent-shaped"). Next is the triquetrum, which is wedge-shaped (this three-sided bone was previously known as "cuneiform", which means "wedge-shaped"; there is a tarsal cuneiform bone as well and this may be the reason for the change in the name). The most medial carpal bone of the proximal row is the pisiform, so named because it looks just like a pea.

Distal row: Starting on the radial side, the trapezium is an irregular four-sided structure just as its name implies. Medially is the trapezoid, also four-sided but smaller than the trapezium. The capitate, formerly called "os magnum" because it's the largest of the carpal bones, has a head-like form as its modern name would suggest. Finally, the hamate bone is hook-shaped; "hamate" and "unciform" both mean "having the shape of a hook", although "hamate" is the modern term.

It is useful for radiologists, orthopedic surgeons, and any other medical professional who might be involved in a discussion of the bones of the wrist to know both the modern and older versions of the names.

A mnemonic device for remembering the modern names of the carpal bones:

"Some Lovers Try Positions That They Can't Handle."

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