Validity study of head and neck flexion-extension motion comparing measurements of a pendulum goniometer and roentgenograms

Abstract

Physical therapists measure head and neck flexion-extension with goniometers, assuming that such measures are an accurate appraisal of joint motion. The only universally accepted, reliable, and objective method of measuring joint motion, however, is by roentgenograms, which have potentially harmful effects and are too expensive to be used routinely for assessing changes in motion. A method is discussed for computing head-tilt on neck and neck flexion-extension motion from roentgenograms. Radiographic measures were compared to pendulum goniometer measures for total head and neck motion (i.e., head-tilt on neck plus neck motion in both the flexed and extended positions) showing good correlation (Pearson=0.97) and good agreement [intraclass correlation (ICC)=0.98] between measures. This study validated that the pendulum goniometer and roentgenograms obtain the same measures for head and neck motion in the sagittal plane.