The hand is a complex of multiple bones of your palms and fingers. The bones in your palm are also called carpal bones. There are eight carpal bones, each with its own shape, function, and location. Within the carpal bones you have eight bones:
- Scaphoid– this bone is located in your wrist, closest to your radius. It is important in creating the wrist joint and helps the mobility of the wrist.
- Lunate– this bone is located in the center of your wrist and helps form its shape as well as aid in flexibility. It is a part of the radiocarpal joint and helps with the movement of your wrist.
- Triquetrum– this bone is important in creating the carpel arch for the carpal tunnel. It is located laterally to the lunate and is a major site of ligament attachment.
- Pisiform– this bone is actually considered a sesamoid bone and functions for attachment of ligaments and tendons. It also acts as a smooth surface for the flexor carpi ulnaris to glide over
- Trapezium– this bone is located just below the thumb joint and plays a role in the stability and movement of the first metacarpal. This bone also touches the scaphoid and the trapezoid.
- Trapezoid– this bone is vital to the movement of the wrist and is a part of the SST joint.
- Capitate– this bone is located in the middle of the carpal bones and functions heavily in the movement of the wrist. It is also a major site of attachment.
- Hamate– this bone is a major bone in the formation of the carpal arch for the carpal tunnel as well as an attachment for the transverse carpal ligament.
Distal of the carpal bones you begin to move into more of a finger-like projection. The next category of bones in your hand is the Metacarpals. The Metacarpals are the tubular bones located distal to the carpal bones and proximal to the phalanges. Within a singular hand, there are five metacarpals numbers I-V.
Each metacarpal is divided into three sections. The first is the head. The head is the most distal part of the metacarpal and creates the joint between the metacarpal and phalange. On the most proximal part of the metacarpal is the base. The base creates the joints between carpal bones and metacarpals. The last part of the metacarpal is the shaft. The shaft is the long middle part of the bone that connects the base and head. The metacarpals are numbers I-V from starting with the pollex.
The final bones of your body are the phalanges. These are the most distal bones in your hand. There are a total of 14 phalange bones found per hand and are also found in your feet. The phalanges are numbered the same as metacarpals. The first phalanges are the bones of the pollex and then move laterally from there. Within each finger, there are 3 bones found, except for in the pollex. The pollex only contains 2 phalanges bones.
The three bones that are found in all the phalanges except for the pollex are categorized as Distal, Intermediate, and Proximal. The Distal Phalange is the furthest bone. The Intermediate phalange is proximal to the distal phalange, except in the pollex where the proximal phalange is proximal to the distal phalange. After the intermediate phalange, the proximal phalange is found.