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.
most common is arthritis. Hip and lower back pain can have many causes, but most common is arthritis. You may have arthritis in your hip as well as your back. It is often difficult to distinguish hip and back arthritis, from back pain with sciatica in conditions such as spinal stenosis or a herniated disc.