Normal global motion of the cervical spine: an electrogoniometric study.

Abstract

Establishment of a normal database and clinical reference of active global cervical spine motion ranges and patterns using a commercial electrogoniometer. Three-dimensional cervical motion ranges and patterns were analyzed in 250 asymptomatic volunteers. In vivo out-of-plane motion patterns of the cervical spine have not yet been reported in large populations, but could be of clinical interest. In 250 subjects (aged 14-70 yr), motion range and patterns between the first thoracic vertebra and the head were analyzed for flexion-extension, lateral bending, rotation in neutral sagittal plane position and in full flexion using the CA 6000 Spine Motion Analyzer. Average motion range in the sagittal plane was 122 degrees (SD: 18 degrees ). Flexion was slightly more important than extension. Out-of-plane components were negligible. Global bending range averaged 88 degrees (SD: 16 degrees ), left and right bending being comparable. Homolateral rotation was associated to lateral bending. Its extent was approximately 40% of the bending range. Global rotation range in neutral sagittal plane position was 144 degrees (SD: 20 degrees ), without significant difference between right and left rotations. Associated motion components were small. During rotation in flexed head position, global range (134 degrees, SD: 24 degrees ) was comparable to the one in neutral flexion. But heterolateral bending, averaging 60% of the primary motion, was associated to flexed rotation. Significant reduction of all primary (but not conjunct) motions with age were obtained. Sex had no influence on cervical motion range. Our results agreed with previous observations, validating the methodology used. They thus constitute reference data of cervical out-of-plane motion for clinical applications.