Evaluation of age-related changes in lumbar facet joints using T2 mapping.

BACKGROUND

The purpose in this study is to investigate the T2 value of lumbar facet joint (FJ) in subjects without lumbar spinal disorders, age from 20s to 70s, using T2 mapping, and to evaluate the correlation between age and T2 value. And also, we investigated the T2 value of lumbar intervertebral disc (IVD) in the same way as FJ, and evaluated the correlation between the T2 value of FJ and that of IVD.

METHODS

We investigated 60 volunteers (30 male, 30 female), who were recruited from six age groups, 20s-70s (10 subjects in each decade; 5 male, 5 female). We measured the T2 values of FJ at the L4/5 level in axial image and those of IVD (nucleus pulposus; NP, anterior and posterior annulus fibrosus; AAF and PAF) at the L4/5 level in midline sagittal image. We investigated the correlation between age and T2 value of FJ, and the correlation between the T2 value of FJ and that of IVD.

RESULTS

There was a strong positive correlation between age and T2 value of FJ (r = 0.717). Age and T2 values of IVD were negatively correlated (NP; r = -0.728, AAF; r = -0.696, PAF; r = -0.580). There was a negative correlation between T2 value of FJ and that of IVD (NP; r = -0.575, AAF; r = -0.617, PAF; r = -0.492).

CONCLUSIONS

T2 value of FJ was significantly increased as age rose. Our results suggest that T2 mapping could detect the degenerative changes of FJ related to aging even in subjects without lumbar spinal disorders. The results of this study will be the reference data of FJ T2 value in order to evaluate the relationship between low back pain and FJ using T2 mapping.