Which carpal bone forms the distal row and articulates with the base of the first metacarpal?

Which carpal bone forms the distal row and articulates with the base of the first metacarpal?

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

Answer: (C)

Think about how the carpal bones organize into two rows and how they connect to the metacarpals. The distal row runs from the thumb side to the little finger as trapezium, trapezoid, capitate, and hamate. The bone at the thumb side that directly articulates with the base of the first metacarpal is the trapezium, forming the carpometacarpal joint of the thumb. This joint provides the thumb’s wide range of motion, including opposition. The other bones mentioned occupy different positions: the scaphoid and lunate are in the proximal row and mainly interact with the radius, capitate articulates with the base of the third metacarpal, and hamate with the bases of the fourth and fifth metacarpals.

Think about how the carpal bones organize into two rows and how they connect to the metacarpals. The distal row runs from the thumb side to the little finger as trapezium, trapezoid, capitate, and hamate. The bone at the thumb side that directly articulates with the base of the first metacarpal is the trapezium, forming the carpometacarpal joint of the thumb. This joint provides the thumb’s wide range of motion, including opposition. The other bones mentioned occupy different positions: the scaphoid and lunate are in the proximal row and mainly interact with the radius, capitate articulates with the base of the third metacarpal, and hamate with the bases of the fourth and fifth metacarpals.