Thank you so much for these nice well explained videos

Thank you!!! This helps so much

Your oblique is more like an oblique abdomen. The standard in Australia is to use an 18x24 (10x8) with a slight up tilt. it is always easier to do it PA as the spine can be directly palpated.

Flexion and extentions should be Standing,,,Peter for Radiologist.

Lead backing to reduce scatter radiation? It is one of those unfortunate traditions passed on through the generations that does nothing at all. In particular, it stops no scatter radiation from the patient from hitting the collector because the grid will deal with that. It will stop a tiny amount of scatter produced extra focal, from tube filtration and from the collimator, but that wouldn't affect image quality anyway. Don't take my word for it. Do some experiments of your own.