CT Scan Study of Atlantoaxial Rotatory Mobility in Asymptomatic Adult Subjects

Abstract

Our results coincide with our previous published ones conducted in children, and lead us to conclude that a CT scan showing wide-but incomplete-rotational facet displacement is not sufficient to define subluxation. We perceive that there is a risk of overdiagnosis and overtreatment (C1-C2 arthrodesis) when evaluating upper cervical spine rotational problems. The concept of both rotatory fixation and subluxation should be revised, and quantifying the rotational angle and contact surface loss between C1-C2 can be very useful.