Clinical assessment techniques for detecting ligament and membrane injuries in the upper cervical spine region--a comparison with MRI results

In this study we examined whether results from a clinical test of passive mobility of soft tissue structures in the upper cervical spine, corresponded with signs of physical injuries, as judged by magnetic resonance imaging (MRI). Results were based on examinations of 122 study participants, 92 with and 30 without a diagnosis of whiplash-associated disorder, type 2. The structures considered were the alar and the transverse ligaments, and the tectorial and the posterior atlanto-occipital membranes. Ordinary and weighted kappa coefficients were used as a measure of agreement, whereas McNemar's test was used for evaluating differences in rating. The clinical classification and the MRI examination both comprised four response categories (grades 0-3), with 0 representing a normal structure, and 3 indicating a structure with pronounced abnormality. In our sample, an abnormal clinical test reflected a hyper- rather than hypo-mobility. Considering all four-response categories, the kappa coefficient indicated moderate agreement (range 0.45-0.60) between the clinical and the MRI classification. The results for the membranes appeared somewhat better than for the ligaments. When there was disagreement, the classifications obtained by the clinical test were significantly lower than the MRI grading, but mainly within one grade difference. When combining grade 0-1 (normal) and 2-3 (abnormal), the agreement improved considerably (range 0.70-0.90). Although results from the clinical test seem to be slightly more conservative than the MRI assessment, we believe that a clinical test can serve as valuable clinical tool in the assessment of WAD patients. However, further validity- and reliability studies are needed.