[Simultaneous rotation and lateral inclination of the head. A clinical sign of restricted motion in segment C1/2].

The clinical diagnosis of a restricted motion at the atlanto-axial level is not always easy. Especially in the presence of a painful restricted neck motion, our clinical tests are unreliable. During a clinical controlled study of patients with dorsal fusions C1-2, we noted a constant and very obvious combined motion of the head: The rotation of the head was not only markedly limited, but it was constantly associated with an ipsilateral tilt of the head. This combined motion of the head can be used as a diagnostic sign of a restricted motion at the atlanto-axial level. Clinical pictures and pathomechanism of this phenomenon are explained.