Quantification of lumbar function. Part 5: Reliability of range-of-motion measures in the sagittal plane and an in vivo torso rotation measurement technique.

Intra- and intertester reliability of a previously described technique for measurement of sagittal plane lumbar spine motion was assessed. Results demonstrated a high degree of reliability of this technique. Sagittal plane norms for men and women are also presented. In addition, a pilot study of a simple in vivo measurement method for lumbar torsion is described and tested on a group of control subjects and a group of chronic low-back pain patients.