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.
View ArthritisVideos. Hip osteoarthritis, a breakdown of cartilage in the hip joint, can often cause symptoms of back, hip, and leg pain. Often, patients with arthritis in the back will also have it in other joints, and it can be difficult to distinguish which area may in fact be the cause of the patient's pain.In fact, a missed diagnosis of hip osteoarthritis as the source of pain is one of the most common causes of failed low back decompression.ip osteoarthritis, a breakdown of cartilage in the hip joint, can often cause symptoms of back, hip, and leg pain.