For patients having a history of lumbar surgeries and chronic back pain, you can try initially to put support under their knees to minimise lumbar strain, if it does not help then you can try the prone position though difficult in an ergonomic design machine.
Wrap the cuffs with the patient lying on his back (without the hoses attached to the treatment table), and then turn him on his abdomen. Long hoses have to be used on all the cuffs. Initially, his torso can be supported with a foam wedge, with his head resting on his forearms. A small pillow can be placed under his shins. The ECG electrodes should be placed posterior to avoid artefacts from the pressure of lying on his torso. This position is well tried and will do well, and the biggest and best surprise would be that the augmentation will be just as good.