Objective: To quantitatively describe the postural alignment of the head and shoulders and the surface curvature of the thoracic spine in comfortable erect standing and to examine the effect of age and gender on head and shoulder alignment.
Design: Descriptive survey.
Setting: Gait research laboratory.
Participants: One hundred sixty asymptomatic volunteers aged between 17 and 83 years.
Main outcome measures: Five photographic measurements of head and shoulder posture in the coronal and sagittal planes and a photographic measurement of the surface curvature of the thoracic spine in the sagittal plane.
Results: Mean values of coronal head tilt, coronal shoulder angle, sagittal head tilt, sagittal C7-tragus angle, and sagittal shoulder-C7 angle were 180.1 degrees, 181 degrees, 172.1 degrees, 131.1 degrees, and 53.7 degrees, respectively. The 95% confidence intervals for the means ranged between 1 degree and 3.8 degrees. For each of the head and shoulder measurements there was no significant gender difference (p = .33 to .99). Of the five measurements, only sagittal C7-tragus angle was significantly correlated with age (r = .44), and none was correlated with surface curvature of the thoracic spine.
Conclusions: Head and shoulder posture was similar between genders. Only one postural description that has been described anecdotally was identified, i.e., that age was related to the position of the head with respect to the trunk in the sagittal plane, although the strength of the association was of questionable clinical significance. In contrast, other longstanding assumptions were not supported, and accordingly, a forward head was not associated with increased thoracic curvature or upper cervical spine extension.