The Value of Indices and Measurements Used for Assessing Functional X-Rays of the Cervical Spine in Clinical Practice

Background: Functional X-ray imaging of the cervical spine in flexion and extension remains a fundamental, objective method for mobility assessment. However, there remains no consensus on how to perform the measurements or which indicators are most useful in clinical practice. Methods: This study included 288 participants (197 female and 91 male); these included patients without CDD signs or with first-degree cervical spine CDD according to the Kellgren-Lawrence criteria. Cobb angle C2-C7, HDI, ROM, CIF, and CIE were measured. Results: The most significant correlations were observed for HDI, and the strongest correlations were between CIF measurements. The greatest mobility was noted for the centrally located segments of the cervical spine, particularly at the C4-C5 level. Conclusions: HDI appears to be the most reliable parameter for characterizing the mobility of the cervical spine. It is precise and has the highest number of correlations with other measurements, but it is very time-consuming. Cobb angle C2-C7 combines ease of performance with good diagnostic value.