The commonest obstacle to the use of this move is the voluntary or involuntary contraction of the neck muscles. The Hook Support, q. v., will limit this resistance by affording a sense of perfect security to the patient. If muscles are _contractured_ a slight “check” will be felt as the head reaches a certain degree of rotation, and beyond this point it will refuse to move though easily movable within the radius limited by the “check.” It is as if the head were held by an inelastic cord. It is best when contracture is present not to attempt moving the head too far but to deliver the movement with the muscles as much relaxed as possible.
[Illustration: Fig. 12. The Rotary, No. 1. Ready for the movement.]
Place patient in position C as described under Technic of Palpation. Stand at head of bench with patient’s head supported by one knee and perhaps also by one hand. Palpate chiefly to discover the numbers of vertebrae, following a record previously made. Finish palpation with the tip of the first finger of either hand resting upon the spinous process of the vertebra to be adjusted.
Consider here which way the vertebra is to be moved; if toward the right use right hand and if toward the left use left hand for adjusting. Draw the adjusting hand straight around until the first finger, about the middle of the proximal phalanx, rests against and _behind_ the transverse process.
It is important that the finger be drawn _straight_ around, and not upward or downward, except with the second Cervical with which the finger may pass slightly upward to the transverse. To insure correct placing of finger let patient’s head be absolutely at rest, supported by the Hook Support with face turned slightly away from the adjusting hand. Reinforce contact finger with the other three fingers held close together behind it. The thumb may or may not be placed against patient’s jaw as desired, but one must be careful not to lose exact contact by drawing adjusting hand upward from a lower Cervical in an attempt to reach the jaw.
Meanwhile the other hand supports the head and holds its weight as described under the Hook Support, q. v.
Next, holding the first finger gently but firmly pressed against the transverse process, turn the head in the direction of the subluxation and away from the adjusting hand. That is, if the vertebra be subluxated to the right turn the face toward the right, the use of the terms “right” or “left” referring to the spinous process.