The trapezium bone is one of the eight small bones that make up the wrist, known as the carpal bones. It is located at the base of the thumb and plays a crucial role in thumb movement and function. The trapezium articulates with the first metacarpal bone, allowing for a wide range of motion, including opposition, which is essential for grasping and pinching. This bone is shaped like a trapezoid, which is where it gets its name. It is situated on the radial side of the wrist, next to the scaphoid and trapezoid bones. Injuries or conditions affecting the trapezium can lead to pain and reduced mobility in the thumb, impacting daily activities.