Figure 1From: Study protocol for patient response to spinal manipulation – a prospective observational clinical trial on physiological and patient-centered outcomes in patients with chronic low back pain Illustration of spinal stiffness assessment tests. Skin marks over bony landmarks of the T11-L5 spinous processes and posterior superior iliac spine (A), palpatory stiffness assessment (B), stiffness assessment with a hand-held device (C); and stiffness assessment with an automated device (D).Back to article page