Bones Of The Hand - Bones Of The Arm - Bones Of The Wrist - Carpal Bones - Radius And Ulna Bones

In this video we discuss the bones of the hand, the bones of the arm and the bones of the wrist. We also cover some of the locations of the joints in this region.


The upper limb or arm and hand contains 30 different bones. The humerus is the largest and longest bone of the upper limb and it makes up the upper portion of your arm.

At the elbow joint it has two curved surfaces. Looking at the skeleton from the front or anterior view, when the skeleton is standing in the anatomical position, face and feet forward and palms facing forward, the outer or lateral curved surface is called the capitulum and the inner or medially curved surface is called the trochea. The capitulum articulates or forms a joint with the radius bone and the trochea articulates with the ulna bone.

The radius and ulna are the bones that make up your forearm. In the anatomical position the radius is located laterally or further from the trunk of the body and the ulna is located closer to the trunk of the body. There are also 2 different joints formed between these two bones called radioulnar joints.

One is located at the upper or proximal parts of the bones near the elbow, and it is called the proximal radioulnar joint and the second is called the distal radioulnar joint and it is near the hand. There is also a membrane called the interosseous membrane between these bones. It is comprised of dense fibrous tissue and it keeps the bones at a fixed distance apart and helps to shift loads or forces between the bones.

At the distal end of the radius, near the hand, is the radiocarpal joint, which is formed between the radius, and 3 of the bones that form part of the wrist. The scaphoid, lunate and triquetrum bones. These 3 bones are called carpals and they form the wrist along with the pisiform, the trapezium, trapezoid, capitates, and hamate bones, giving a total of 8 carpal bones. The distal carpals articulate with the bones of the palm, called the metacarpals.

There are a total of 5 metacarpals, which are denoted by roman numerals 1 thru 5 with 1 located at the base of the thumb and 5 at the base of the little finger. The bones of the fingers are called phalanges. The thumb consists of 2 phalanges with the second thru fifth fingers having 3 phalanges each.

The thumb, also called the pollex has a proximal phalanx of pollex near the palm and a distal phalanx of pollex away from the wrist. Distal meaning away from the body and proximal meaning closer to the body. The second thru fifth fingers each have a proximal phalanx, a middle phalanx and a distal phalanx.

Timestamps
0:00 The humerus bone
0:10 The elbow joint
0:30 The ulna and radius
1:20 The wrist
1:45 The palm of the hand - metacarpal bones
2:00 The fingers - phalanges