Relating a manual medicine diagnostic test of cervical motion function to specific three-dimensional kinematic variables

Abstract

Background The Bone and Joint Decade 2000–2010 Task Force on Neck Pain and its Associated Disorders (BJD) indicates that there is a significant shortage of scientific research to support manual therapies in diagnosis and treatment, specifically for the cervical region. Objective The purpose of this research was to quantify motions associated with the palpatory diagnostic procedure of cervical lateral flexion using three-dimensional (3-D) motion capture techniques. Further, these data were examined for relationships with the clinical diagnosis. Design setting 3-D kinematic data were examined for relationships to a palpatory diagnostic test of cervical lateral flexion. Methods A five-camera video based motion system was used to collect 3-D data during passive cervical lateral flexion. These data were then used to compute head movements relative to the thorax. Statistical analysis of the angular data included non-parametric tests, binary logistical regression and cluster analysis. Subjects Eighty-five subjects were classified into two groups: asymptomatic ( n = 76) with a VAS < 4, and symptomatic (reporting neck pain on the day of the experiment) with a VAS ≥ 4/10 ( n = 9). Only asymptomatic subjects with symmetrical passive cervical lateral flexions as determined by the blinded consensus of two experienced and trained examiners were included in the study ( n = 10). Results Symptomatic subjects exhibited significantly greater kinematic differences between repeat trials of the diagnostic test as compared to asymptomatic subjects. The data also suggests a trial dependent “warm up” effect. Further, the cluster analysis of the difference measure showed the potential of kinematic analysis to discern between the two subject groups. Conclusions Results from this study demonstrate the ability to generate objective data that can be related to a manual medicine diagnostic test. This methodological approach may serve as a foundation for additional kinematic studies of manual medicine techniques, as well supporting work for documenting treatment outcomes and to assisting in teaching and training clinicians.