The slow and fast components of postural sway in chronic neck pain

Several studies have reported altered postural control in people with neck pain. The aim of this study was to increase the understanding of the nature of altered postural control in neck pain by studying the slow and fast components of body sway.

Subjects with whiplash associated disorders (WAD, n = 21) and chronic non-specific neck pain (NS, n = 24) were compared to healthy controls (CON, n = 21) in this cross-sectional study. The magnitudes of the slow and fast sway components were assessed in Rhomberg quiet stance for 30 s on a force plate with eyes closed. We also investigated associations between postural sway and symptoms, self-ratings of functioning and kinesiophobia.

Increased magnitude of the slow sway component was found in WAD, but not in NS. Greater magnitude of the slow component in WAD was associated with poorer physical functioning, including balance disturbances, and more severe sensory symptoms.

Increased magnitude of the slow sway component implies an aberration in sensory feedback or processing of sensory information in WAD. The associations between postural sway and self-rated characteristics support the clinical validity of the test. Further investigation into NS, involving a longer test time is warranted.