Comparison of Posteroanterior Spinal Stiffness Measures to Clinical and Demographic Findings at Baseline in Patients Enrolled in a Clinical Study of Spinal Manipulation for Low Back Pain

The PAS system of computer-monitored equipment with human operation performed well in this clinical study of LBP. Spinal stiffness was found to be different between males and females, and age and body mass index were related to PAS. We found no significant relationship between the severity or chronicity of the LBP complaint and spinal stiffness. There was little agreement between the stiff or tender segments identified by the clinicians using palpation and the segment that measured most stiff using the PAS device.