Measurement of the Kinematics of the Lumbar Spine in vivo

Low back pain is a very common problem, particularly in industrialised countries. In addition to the enormous cost to the economy, the scale of the misery arising is considerable. Mechanical damage is often felt to be an underlying cause of the pain and, certainly, lumbar spine instability is a topic of much current interest. Determination and characterisation of instability is, however, fraught with problems, not least being the difficulty if observing spine motion.