The influence of neck torsion and sequence of cycles on intra-trial reliability of smooth pursuit eye movement test in patients with neck pain disorders

The sensory mismatch commonly observed in patients with neck pain disorders could alter intra-trial reliability in simple implicit smooth pursuit eye movement tasks. This could be more pronounced when neck is in torsioned position (SPNT). The aim of this study was to explore the effects of neck torsion, target movement velocity and amplitude on intra-trial reliability of smooth pursuit eye movements in patients with neck pain disorders and healthy individuals. SPNT test was evaluated in 32 chronic neck pain patients and 32 healthy controls. Ten cycles were performed using video-oculography at three different velocities (20 degrees s(-1), 30 degrees s(-1) and 40 degrees s(-1)) and at three different amplitudes (30 degrees, 40 degrees and 50 degrees) of target movement. Intra-trial reliability and differences between average gain and SPNT difference from the second to fifth cycle and from the sixth to ninth cycle were assessed using ICC3.1 and factorial analysis of variance, respectively. Intra-trial reliability for gain and SPNT difference at all target movement amplitudes and velocities proved to be good to excellent in both observed groups. Patients with neck pain disorders presented with a trend of inferior gain performance between the sixth and ninth cycle at 30 degrees s(-1) of target movement as compared to healthy individuals which was only evident when neck was in torsioned position. Although intra-trial reliability of smooth pursuit neck torsion test is good to excellent, the effects of learning are not as pronounced in patients with neck pain disorders.

Automated summary

The study aimed to investigate the effects of neck torsion, target movement velocity, and amplitude on the intra-trial reliability of smooth pursuit eye movements in patients with neck pain disorders and healthy individuals. The results showed that the intra-trial reliability for gain and SPNT difference was good to excellent in both groups, but patients with neck pain disorders showed inferior gain performance between the sixth and ninth cycle at 30 degrees/s of target movement when the neck was in torsion position. The study suggests that learning effects may be less pronounced in patients with neck pain disorders.