Prince of Fatness
I'm not a regular poster on the daily but remember you having these problems for a while. This hits close to home for me since I have had lower back / hamstring issues for almost two months now and have had to cut back on my running. It is very frustrating not having an answer and consequently a timetable for getting back on the roads. So I suppose I feel your pain to a small degree.
I hope you find an answer and get back to running regularly again. Good luck.
Not at it at all.