[Reliability of functional x-ray analysis of cervical vertebrae flexion and extension]

Functional radiographic analysis of the cervical spine in flexion and extension position is increasingly used as screening method for the diagnosis of segmental functional disorders. The objective of this study was to prove Penning's evaluation method for the metrical recording of segmental angles in the sagittal plane for selectivity, reliability and usability. Passive functional radiographs of the cervical spine in flexion and extension were taken of 20 patients with painful limitation of mobility of the cervical spine and 20 subjects, similar in sex and age, without complaints. The radiographs were duplicated. Five physicians measured the angles of segmental mobility in a blind study. Statistical analysis was conducted using the t-test and calculating the correlation coefficient "r". The results of the study prove that the evaluation method by Penning shows a usable and, for segments C3/C4 to C6/C7, significant selectivity. The selectivity of p < or = 0.05 and p < or = 0.01 is sufficient to distinguish patients from healthy subjects. The correlation between the five reviewers showed good to very good results (0.6 < r < or = 0.8; r > 0.8). The measured values, however, have to be considered, in connection with the appropriate clinical symptoms, as still "normal" or "functionally disordered" in the context of segmental hypo-resp. hypermobility.