Risk factors in Klippel-Feil syndrome

This study kinematically evaluated radiographs of the cervical spine of patients with the Klippel-Feil syndrome in flexion and in extension to determine alterations from normal motion and potential risk.

The results in the study group were compared with those of a control group and with published standards for expected motion of the cervical spine.

The body of orthopedic and neurologic literature suggests a significant problem with neurologic deficit in patients with Klippel-Feil syndrome. No previous study has evaluated the kinematics of the cervical spine with a control group of normal individuals and published standards.

Lateral flexion-extension radiographs of the cervical spine of 111 patients with Klippel-Feil syndrome were kinematically evaluated to determine the motion of each open interspace and to compare motion with that of a control group and published standards.

A statistically significant difference of increased motion per open interspaces in the upper cervical segment was noted in individuals with Klippel-Feil syndrome when compared with the control population. Conversely, total motion of the lower cervical segment was significantly decreased in the Klippel-Feil population when compared with normal controls. Lower segment motion per open interspace was not significantly different when the two groups were compared.

The results of this study suggest that individuals with Klippel-Feil syndrome with hypermobility of the upper cervical segment are at risk for neurologic sequelae, whereas those with alteration in motion of the lower cervical segment are predisposed to degenerative disease.