Dear beazus
How are you? My feeling is the physical examination has not matched up with the sujective assessment yet. From your physical examination, the mind points towards a systemic problem. By vascular issues, I mean compressions of lowerlimb vessels with certain positions akin as you would find in some cyclist who complain of leg pain. I have seen this, and it turned out to be caused by narrowing of vessels flowing from the abdomen to the lowerlimbs...
Again, this reasoning is coming from the physical examinations you have done...it is hard to say unless one sees this lady physically
If I take away your physical examnation and just look at the presentation you describe only, it really looks like aspondylolisthesis... the markers are
1) bilateral inguinal and radiating thigh pain- (I have seen this before)
2) feeling of weakness in the lowerlimbs
3) inability to extend, avoiding prone
4) dffuse pain pattern generally in the lumbar area could suggest several problems,from visceral, inflamatory spine problems, dural matter problems...it can be seen in spondylolisthesis if it has become a larger grade shift as physiobob means...because of irritation of more central structures
you are right, a simple xray should help confirm or refute this hypothesis and yes, you are definitely on point giving more focus on the back...I have suggested anMRI because you could have this same presentation in a large disc herniation, something a simple xray is unlikely to pick up
I would suggest suspending any physiotherapy input until you have the results of even if it is just your xray referral...if it is a spondylolisthesis, those exercises you have given can aggravate the condition
Good luck and keep us posted, it is good to know the actual diagnosis