OBJECTIVE: To determine whether vestibular or cervical proprioceptive information influence the cervicocephalic relocation test to the neutral head position, by comparing head repositioning errors obtained in asymptomatic, unimpaired control subjects with those obtained in bilateral labyrinthine-defective patients and chronic, nontraumatic neck pain patients. DESIGN: A group-comparison study. SETTING: University medical bioengineering laboratory. PARTICIPANTS: Labyrinthine-defective patients (n=7; mean age+/-SD, 67+/-15 y), nontraumatic neck pain patients (n=7; 56+/-9 y), and asymptomatic, unimpaired control subjects (n=7; 64+/-12 y). INTERVENTIONS: Participants were asked to relocate the head on the trunk, as accurately as possible, after full active cervical rotation to the left and right sides. Ten trials were performed for each rotation side. MAIN OUTCOME MEASURES: Absolute and variable errors were used to assess accuracy and consistency of the repositioning, respectively. RESULTS: No significant difference in repositioning errors was observed between labyrinthine-defective patients and control subjects, whereas nontraumatic neck pain patients demonstrated significantly increased absolute errors in horizontal and global components and higher variable errors in horizontal component. CONCLUSIONS: These findings suggest that the vestibular system is not involved in the performance of the cervicocephalic relocation test to neutral head position, and further support this test as a measure of cervical proprioceptive acuity.
OBJECTIVE: To determine whether vestibular or cervical proprioceptive information influence the cervicocephalic relocation test to the neutral head position, by comparing head repositioning errors obtained in asymptomatic, unimpaired control subjects with those obtained in bilateral labyrinthine-defective patients and chronic, nontraumatic neck painpatients. DESIGN: A group-comparison study. SETTING: University medical bioengineering laboratory. PARTICIPANTS: Labyrinthine-defective patients (n=7; mean age+/-SD, 67+/-15 y), nontraumatic neck painpatients (n=7; 56+/-9 y), and asymptomatic, unimpaired control subjects (n=7; 64+/-12 y). INTERVENTIONS:Participants were asked to relocate the head on the trunk, as accurately as possible, after full active cervical rotation to the left and right sides. Ten trials were performed for each rotation side. MAIN OUTCOME MEASURES: Absolute and variable errors were used to assess accuracy and consistency of the repositioning, respectively. RESULTS: No significant difference in repositioning errors was observed between labyrinthine-defective patients and control subjects, whereas nontraumatic neck painpatients demonstrated significantly increased absolute errors in horizontal and global components and higher variable errors in horizontal component. CONCLUSIONS: These findings suggest that the vestibular system is not involved in the performance of the cervicocephalic relocation test to neutral head position, and further support this test as a measure of cervical proprioceptive acuity.