The influence of age, anthropometrics and range of motion on the morphometry of the synovial folds of the lateral atlanto-axial joints: a pilot study

The purpose of this study was to investigate the effect of age, anthropometrics and cervical range of motion upon synovial fold volume. Ten healthy female subjects aged 20–40 years were included in the study. Age, height, body mass, dimensions of the head and neck and cervical range of motion of each subject were measured. Magnetic resonance (MR) images of the cervical spine were acquired; the volume of the ventral and dorsal synovial folds of the right and the left lateral atlanto-axial joints was measured using seed growing and thresholding methods. Using Spearman’s correlation coefficient, it was determined that there was no correlation between synovial fold volume and age. Synovial fold volume was positively correlated with subject height and neck length but negatively correlated with body mass, body mass index and the circumference of the head and neck. The relationship between synovial fold volume and range of cervical motion varied with the plane of movement. The ability to image the synovial folds of the lateral atlanto-axial joints using MR imaging to determine their normal morphology provides the basis for investigating synovial fold pathology in patients with neck pain and headache.