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.
4. Leg, Back or Side Pain. Kidney problems can lead to pain in the back, side or even in the leg. Kidney cysts (large, fluid-filled sacs) resulting from polycystic kidney disease that form on kidneys and occasionally on the liver can also cause back and leg pain.