The center lines of the back and front photography of the hand should be aligned.

The center lines of front and back hand photography should be aligned: the distal end of the second metacarpal bone.

Supplementary information:

Breathing patterns for back and front photography are as follows:

1. Photographing position: The examinee sits on one side of the photographic bed, with wrist joints and fingers straight, palms down, fingers straight and naturally separated, and flat on the IR. The third metacarpal bone is placed in the center of IR, and the upper edge of IR includes phalangeal soft tissue and the lower edge includes wrist joint. When taking pictures with both hands at the same time, the examinee faces the photographic bed, his arms are stretched forward, and the chapter face is placed symmetrically on IR.

2. The midline is aligned with the third metacarpal bone for vertical injection. If both hands are ingested at the same time, the center line is injected vertically through the midpoint of the third metacarpal line of both hands.

3. The image shows that the metacarpophalangeal bones of 2-5 sides are in an upright position, and the metacarpophalangeal bones of the thumb are in an inclined position. Bone trabecular display is clear and soft tissue display is good.

There are 13 bones in the palm, including 5 metacarpals and 8 wrists.

The metacarpal bone is a very small long bone, and the joint related to the phalanx is 1 ~ 5 metacarpal bone from the radial side to the ulnar side (that is, thumb to tail finger).

Carpal bone is a short bone, located at the proximal end of hand bone, divided into two rows, each with 4 pieces, all named after its shape. From radius to ulna, the nearest rows are scaphoid, lunate, triangle and pisiform bone. The distal column has polygonal bone, small polygonal bone, skull and hamate.