Inter-tester reliability of passive intervertebral and active movements of the cervical spine

Measurements of active range of motion (AROM) and passive intervertebral movements (PIM) of the cervical spine are frequently used for patients with neck pain. However, there is a paucity of studies that investigate the psychometric properties of these measurements. Objectives of this study were to: (1) determine the inter-tester reliability of PIM, AROM, and the effects of AROM on symptom provocation; (2) establish the minimal detectable change (MDC) in cervical AROM; and (3) determine the association between AROM and disability. Thirty subjects (age 41+/- 12) with neck pain participated in this study. Two masked examiners performed the measurements during the same testing session. PIM was assessed manually and recorded as hypomobile or normal. AROM was measured in degrees with a gravity goniometer. The effect of AROM on patient's symptoms was recorded as no change, decreased, increased, centralization, or peripheralization. Measures of AROM had moderate to substantial reliability (.78 - .91) and resulted in a MDC adequate for clinical use (from 9 degrees to 16 degrees). The effect of AROM on symptom provocation resulted in Kappa values that ranged from slight to substantial (.25 - .87). Measures of PIM resulted in substantial and moderate reliability of assessing occipital-atlas mobility, tenderness of the transverse processes of atlas, and symptom provocation during PIM testing of the lower cervical segments. Fair Kappa values were observed during judgment of mobility in the C2 segment and symptom reproduction during PIM of C2 and C5. The additional PIM had Kappa values that ranged from none to slight. Low prevalence of positive findings likely resulted in an artificial deflation of the Kappa statistic during some PIM measures. Measures of AROM in saggital and transverse planes were associated with disability scores (r = .43 and .40, respectively). Findings are relevant to the planning of future studies to establish the criterion validity of these tests to guide the selection of interventions and establish prognosis in patients with neck pain.