Head and neck position sense in whiplash patients and healthy individuals and the effect of the cranio-cervical flexion action

Background. Whiplash may damage structures within the neck that can affect position sense. Deep neck flexor muscle retraining may improve position sense. The current study compared range of motion and position sense in whiplash and control subjects and investigated the effects of a muscle training session on position sense. Methods. Twenty-three subjects with whiplash were compared with a matched control group. Range of motion and neck position sense measures were recorded using the 3-Space Fastrak. Measures of function were also assessed in the whiplash group. Subjects were then randomised into experimental and control groups and the former group received a training session to activate the deep neck flexor and scapular stabilising muscles (the cranio-cervical flexion action) during head and neck movements. After training, position sense measures were re-evaluated. Findings. Results showed significant reductions (P < 0.05) in active range of motion in the whiplash group when compared to the healthy group. No significant differences (P > 0.05) between whiplash and healthy groups in position matching accuracy were observed. Functional outcome scores indicated the whiplash group to be mildly disabled. No effect on error scores was observed when position-matching tasks were performed with and without the cranio-cervical flexion action. Correlations between functional measures or range of motion, and position sense were not significant. Interpretation. There was no evidence of position sense impairment in the mildly disabled whiplash subjects. The performance of the cranio-cervical flexion action had no effect on position sense, and hence clinical improvements observed from using this action may be more associated with mechanical stabilisation.