Relationships between sagittal postures of thoracic and cervical spine, presence of neck pain, neck pain severity and disability.

This was a cross-sectional correlation study to explore the relationships between sagittal postures of thoracic and cervical spine, presence of neck pain, neck pain severity and disability. Moreover, the reliability of the photographic measurement of the sagittal posture of thoracic and cervical spine was investigated. Forty-five subjects without neck pain and forty-seven subjects with neck pain were recruited. Using a photographic method, the sagittal thoracic and cervical postures were measured by the upper thoracic and the craniovertebral (CV) angles respectively. The Numeric Pain Rating Scale (NPRS) and Chinese version Northwick Park Neck Pain Questionnaire (NPQ) were used to assess neck pain severity and disability. The upper thoracic angle was positively correlated (r(s) = 0.63, p < 0.01) while the CV angle was negatively correlated (r(s) = -0.56, p < 0.01) with the presence of neck pain. The upper thoracic angle was negatively correlated with the CV angles (r(s) = -0.62, p < 0.01) in subjects with neck pain. Similar to the CV angle, the upper thoracic angle was moderately correlated with the neck pain severity (r(s) = 0.43, p = 0.01) and disability (r(s) = 0.44, p = 0.02). The upper thoracic angle (OR = 1.37, p < 0.01) was a good predictor for presence of neck pain even better than that of the CV angle (OR = 0.86, p = 0.04).