The back and the nape of the neck are projected on the upper part of the hand and foot.

In the Main system the projection of the back is divided into two parts. On the thumbs and the big toes the neck (on the second phalanx) and the part of the back to the 8th thoracic vertebra (on the first bone before the wrist and the first bone before the foot) are projected. The rest of the back, from the 9th thoracic vertebra downwards, is projected on the adjoining to the thumbs upper part of the palm and the foot.

In the “Insect” system the neck is projected on a small area between the first and second phalanges of the fingers and toes. On the middle phalanges of the fingers and toes the part of the back from 8th thoracic vertebra is projected, and on the proximal (third) phalanx – the part of the back from 9th thoracic vertebra downwards.