An exploratory study examining factors underpinning postural instability in older adults with idiopathic neck pain.

There is limited understanding of potential mechanisms underpinning postural control deficits in people with neck pain. This study examined several characteristics that might explain impaired postural stability in a group of older adults with neck pain, and compared the results in this cohort with that of asymptomatic controls. In this cross-sectional study we compared physical activity, lower limb motor and sensory function, vestibular and visual function, falls efficacy and dizziness handicap in 84 older adults with (n=35, age 69.6±6.3) and without (n=49, age 69.4±4.7) idiopathic neck-pain. Additionally, dynamic balance was assessed using the dynamic gait index (DGI) and standard and wavelet analysis of static balance was computed after data capture. Physical activity levels, lower limb motor and sensory function, vestibular function and visual contrast sensitivity were not different between groups (p>0.05). The neck-pain group demonstrated higher falls efficacy (p=0.01), greater levels of dizziness handicap (p<0.01), and higher CoP velocity measures in the moderate (1.56-6.25Hz) and low (0.39-1.56Hz) frequency bandwidths. Our results suggest that neck-pain induced postural control deficits in older adults may not be associated with the physical activity levels, lower limb motor and sensory function, or vestibular and visual function. Inferring from wavelet analysis results, we speculated that sensory re-weighting may have occurred to compensate for the deficits in neck proprioception. Further research is warranted to determine neck specific mechanisms underpinning postural control dysfunction in neck pain.