On average among OECD countries, there are about 14 students. per teacher at the secondary level (Table D2.2). As the differences in student-teacher ratios indicate, there are fewer full-time equivalent students per full-. time equivalent teachers at the secondary level than at the primary level of education.
Causes of Lower Back Pain. Home/Conditions/Causes of Lower Back Pain. Pain in the lower back has a multitude of causes. The discs, facets, pars interarticularis, sacroiliac joints, hip joints and nerves can all cause a form of lower back pain.
How Tight Hips Can Cause Lower Back Pain. In my experience as a personal trainer for 5 years Iâve noticed that tight hips lead to lower back pain. I always like to use the analogy of a hammock when referring to how the body works with regard to tight muscles, connective tissue, tendons and ligaments.