Abstract

OBJECTIVE:

To investigate the reliability and discriminative ability of a new test designed to detect accuracy of neck movements.

DESIGN:

Repeated-measures. Case-control.

SETTING:

University musculoskeletal research clinic in Iceland.

PARTICIPANTS:

Twenty women (mean age +/- standard deviation [SD], 30.8+/-9.1 y; range, 18-49 y) with chronic whiplash-associated disorders (WAD) grades I and II (duration, 6 mo-6 y), with current pain score on a visual analog scale of 46.8+/-21.8, and a disability score on the Northwick Park Neck Pain Disability Index of 45%+/-14%. Twenty asymptomatic women (mean age +/- SD, 29.3+/-8.6 y; range, 18-48 y) with no history of whiplash or insidious onset neck pain served as controls.

INTERVENTION:

A slowly moving object appeared on a computer screen and traced an unpredictable movement path that the subjects were required to follow by moving their heads. Three randomly ordered movement patterns were tested.

MAIN OUTCOME MEASURE:

A new software program connected to a 3Space Fastrak system was used to measure the mean absolute error (in millimeters) of 3 trials in each movement pattern.

RESULTS:

The mean differences (+/-2 SD) between days 1 and 2 were.01+/-.64 mm for the asymptomatic group and.33+/-1.80 mm for the WAD group. The between-day intraclass correlation coefficients were between.60 and.77 for the asymptomatic group and.79 and.86 for the WAD group. Repeated-measures analysis of variance revealed a significant difference between groups (P=.02). The Tukey post hoc test showed significant between-group differences for each movement pattern (P</=.05). In each successive trial, a slight improvement for the asymptomatic group and a slight worsening for the WAD group were detected.

CONCLUSIONS:

Better reliability was detected for the asymptomatic group than for the WAD group. The test could discriminate between the asymptomatic group versus the chronic WAD group.