Discriminative validity of sensory evaluation in a whiplash-associated disorder II population

Methods: Single-blinded, case control observational study using a convenience sample of 20 participants (median age 28.5 years, low disability) with chronic grade II whiplash-associated disorder (CWADII) and 22 control participants (median age 26 years) with no history of whiplash/neck injury. Outcome measures included vibration and cold pain perception threshold, and joint position error.

Aim: Evidence suggests chronic whiplash is associated with sensory hypersensitivity. Understanding the degree of sensory impairment could enhance rehabilitation strategies. This preliminary study determined whether differences in sensory evaluation occur post whiplash injury.

Results: Significant associations using Kendall’s tau correlation coefficient were found between: vibration thresholds (thenar and hypothenar eminences) for the CWADII group (p<0.01); cold pain thresholds (thenar, 5th metacarpophalangeal, mid cervical spine) in both groups (p<0.01); joint positioning errors (global positioning following right/left rotations, left rotation/extension) (p<0.01) in the CWADII group; and between vertical direction errors (following right/left rotation) in both groups (p<0.01). Discrimination between groups was not identified using separate logistic regressions on vibration or cold pain thresholds (thenar eminence) or on global flexion/extension/right rotation position errors (p>0.01).

Conclusions: The findings do not support the use of vibration, cold pain threshold or joint position error to identify individuals with CWADII with low disability.