Study design: Cross-sectional study.
Objective: To investigate associations between subclinical neck pain/discomfort, and range of motion and physical dimensions of the cervicothoracic spine.
Summary of background data: Despite the high prevalence of neck problems, few studies are available indicating any physical associations with the development of neck pain, or information regarding early signs of pathology from neck pain for subjects not in treatment.
Methods: Forty healthy volunteers, between 19 and 42 years of age (mean age 28 years), were recruited. The dimensions of the cervicothoracic spine measured were as follows: spinal posture, active cervical range of motion, and segment length of the neck. All measurements were taken twice from each subject by different testers, on the same occasion. Cervical muscle endurance was measured by a modified Biering-Sørensen Test. Finally, subjects were questioned about any recurrent neck pain/discomfort.
Results: Fourteen subjects reported experiencing low-level neck pain/discomfort on a recurrent basis. Neck muscle endurance time (F1,38 = 6.75, P = 0.01) and left rotation end-of-range (F1,38 = 4.56, P = 0.04) were found to be significantly lower for subjects with neck pain. Extension end-of-range showed a group-specific change at retest, increasing for subjects without pain, but decreasing for those with neck pain (F1,38 = 4.67, P = 0.04). This same group had a greater range of retraction than the asymptomatic group (F1,38 = 4.56, P = 0.04). Subjects overall, irrespective of pain classification, demonstrated greater left rotation than right rotation (F1,38 = 4.34, P = 0.04) and also showed reduced side flexion on the left (F1,38 = 5.10, P = 0.03) and right (F1,38 = 5.27, P = 0.03) with repeated measurement.
Conclusions: Between-groups differences were observed as lower neck muscle endurance time, reduced left rotation, relatively reduced extension at second test, but greater range of retraction, when the subclinical and normal groups were compared. These data suggest that there are early range changes associated with the development of neck pain.