Anatomy/Bones of the Upper Limb
Bones of the Shoulder
The shoulder is comprised of the scapula (shoulder blade), and the clavicle (collar bone).
Bones of the Arm
The bone in the arm is the humerus.
Bones of the Forearm
The forearm is comprised of the radius and the ulna, which run parallel to each other. The radius is lateral to the ulna.
Bones of the Hand
The wrist is comprised of the carpal bones, a number of relatively small bones roughly arranged in two rows of four, which are known collectively as the carpus. The proximal row is the first row, and is comprised of (in order from lateral to medial side):
- Scaphoid (navicular) bone
- Lunate bone
- Triquetral (triangular) bone
- Pisiform bone: Anterior to the triquetral bone.
The distal row is comprised of:
- Trapezial (greater multangular) bone
- Trapezoid (lesser multangular) bone
- Capitate bone
- Hamate bone
The carpal bones can be remembered using the following (somewhat humerous - no pun intended) rhymes:
- Sometimes lovers try positions that they cannot handle. or
- She looks too pretty. Try to catch her. or
"So long to pinky, here comes the thumb."
- Sam Likes To Push The Toy Car Hard.
Distal to the carpal bones is the metacarpus, comprised of the metacarpal bones. These run through the palm of the hand, and connect the fingers to the carpus. There are five metacarpals, and they are numbered starting with the lateral side from one to five, the first metacarpal running to the thumb.
Distal to the metacarpus are phalanx bones, or the phalanges. These are the digital bones, consisting of three in each finger, except for the thumb which contains only two. As the phalanges are arranged in rows, they are referred to by their row number, and finger number. Each finger is numbered similarly to the metacarpals, from one to five beginning with the lateral thumb. The first row of phalanges are called the proximal phalanges, the second row as the middle phalanges, and the third row as the distal phalanges. For example, the second middle phalanx is the middle bone of the index finger. As the thumb contains only two phalanges, these are referred to as the first proximal and first distal phalanges.