[Voluntary activity of the neck muscles in patients with spastic torticollis]

The authors investigated the characteristics of motor disorders in patients with spastic torticollis. The study involved registration of volitional tensions of the neck muscles in isometric conditions, i.e., when the patient's head was rigidly fixed with regard to the body. Using a tensometric dynamometer the following three moments of force were measured: one responsible for bending the head forward or backward; the second, for bending the head to the right or left shoulder; and the third, for turning the head round the longitudinal axis. The electrical activity of the neck muscles was recorded with the help of surface electrodes. It has been established that the development of volitional efforts by the neck muscles under isometric conditions is difficult or impossible if directed to the side where the patient's forcible turn of the head is directed.