Validation of the Cervical Torsion Test and Head Neck Differentiation Test in Patients with Peripheral Vestibular Hypofunction.

Abstract

This study compared adults with peripheral vestibular hypofunction (VH) to healthy controls and assessed the sensitivity and specificity of the Cervical Torsion Test (CTT) and the Head Neck Differentiation Test (HNDT). This study aimed to determine whether neck problems affected primary outcomes. This cross-sectional study included adults from a specialist consultation for dizziness. VH had been diagnosed with the video Head Impulse Test. Exclusion criteria were conditions following head or neck trauma and diseases of the central nervous system. Sensitivity and specificity of the index tests were calculated, and regression analyses were performed to test for contributing factors. A total of 19 patients with VH and a historical cohort of 19 matched healthy controls were included. Most patients with VH (84.2%) experienced symptoms in at least 1 test component, compared to 5.2% of the control group. Of patients with VH, 78.9% had symptoms during the HNDT "en bloc" (en bloc = head and trunk rotated together) whereas only 26.3% reported symptoms during the CTT en bloc. Best discriminatory validity was found for the HNDT en bloc, with a sensitivity of 0.79 (95% CI = 0.54-0.94), a specificity of 0.86 (95% CI = 0.65-0.97), and a positive likelihood ratio of 5.79 (95% CI = 1.97-17.00). The number of symptoms of CTT "in torsion" (in torsion = trunk rotated actively with fixed head) was increased by a factor of 1.13 (95% CI = 1.01-1.27) for every additional point on the Neck Disability Index. The CTT and HNDT can serve as nonlaboratory tests in patients with dizziness. The HNDT en bloc has the best discriminatory validity, finding those with and those without VH. Symptom reproduction during torsion may help to identify when neck problems may contribute to dizziness. The HNDT en bloc may be useful for ruling VH in or out in patients with dizziness. Positive CTT and HNDT in torsion components may verify the likelihood of additional neck involvement.