The hand consists of 54 bones separated into three distinct regions: the wrist (carpals), the palm (metacarpals), and the finger digits (phalanges).
The eight carpal bones are the bones of the wrist. They largely assist in motility and support of the hand .
- The scaphoid bone is slightly larger than the other carpal bones and lies near the thumb. The scaphoid's name is derived from the Greek word "skaphe," meaning boat.
- The lunate bone, also known as the semilunar bone, is a crescent shaped bone. The lunate bone is one of the most frequently dislocated bones of the wrist region. The lunate bone's name is derived from the latin word "luna," meaning moon.
- The triquetral bone is triangular in shape and is thus also known as the triquetrum bone, three-cornered bone, pyramidal bone, and triangular bone.
- The pisiform bone, also known as the lentiform bone, is a small round bone. Unlike many other carpal bones, the pisiform bone is a sesamoid bone since it is located within a tendon. The origin of the pisiform is the Latin word "pīsum," meaning "pea" since the pisiform is shaped somewhat like a pea.
- The trapezium bone is quadrilateral in shape and articulates with the scaphoid bone. The trapezium is also known as the greater multiangular bone.
- The trapezoid bone is a wedge shaped bone. The trapezoid bone is also known as the the lesser multiangular bone and its name is derived from the Greek word "trapezion," meaning irregular quadrilateral.
- The capitate bone is the largest bone of the carpal region and lies in the center of the wrist. The capitate bone's name is derived from the Latin word capitātus, meaning "containing a head," because the capitate contains a rounded surface known as the head.
- The hamate bone, also known as the unciform bone, is a wedge shaped bone. The hamate bone is commonly fractured in sports related injuries. The hamate's name is derived from the Latin word "hamatus," meaning hooked.
Each hand consists of five metacarpal bones . The metacarpal bones are located in the metacarpus (palm region). They lie in between the carpus and the phalanges (fingers). The metacarpal bones' primary functions include hand motion, hand support, and providing the shape of the hand.
The phalanges consist of three sections , the proximal phalanges, the intermediate phalanges, and the distal phalanges. Collectively, these bones make up the structure known as the fingers. All of these bones play an important role in hand motion and function. The proximal phalanges are found at the base of the fingers, closest to the carpus. These bones are longer than the carpal bones. There are five proximal phalanges per hand. The intermediate phalanges are found in between the proximal phalanges and the distal phalanges. There are four intermediate phalanges found on each hand because the thumb lacks an intermediate phalange. The distal phalanges are a series of bones found at the tip of the hand, following the intermediate phalanges. There are five distal phalanges per hand.