The displacement, velocity and frequency profile of the frontal plane motion produced by the cervical lateral glide...

To investigate the specificity of linear and angular displacement, peak velocity and frequency of oscillation of the frontal plane motion produced by the lateral glide treatment technique of the cervical spine.

A within-subjects design was used.

The lateral glide treatment technique of the cervical spine has previously been shown to produce specific neurophysiological effects, whereas the technique's biomechanical effects remain uninvestigated. A relationship may exist between a technique's biomechanical effects and its clinical outcome.

Eight asymptomatic subjects participated in the study. Retroreflective markers were placed dorsally at the occiput, and the C5, T1, T3 and T5 vertebrae. Movement of these markers was recorded by a video processor. The same physiotherapist applied the treatment technique to each subject.

Linear displacement (3.336 cm) and peak velocity (13.643 cm/s) between C5 and T1 markers was greater than between T1 and T3, Occiput and C5, and T3 and T5. Angular displacement about C5 (26.5 degrees ) was twice that about T1 and T3, but unlike T1 and T3 occurred in the opposite direction to that of the treatment technique. Frequency of oscillation was 1. 255 Hz.

The lateral glide treatment technique produced a characteristic ipsilateral displacement rather than side flexion, predominantly at its region of application.

This study provides the basis for further investigations of the mechanisms of action of the lateral glide treatment technique. It also provides clinicians with guidelines for the application of this technique.