From UK HSE.........
Low back pain is common and can be extremely painful. It can be difficult to cope with the severe pain but fortunately it is rarely due to serious disease. There are things that employers and workers can do to manage back pain and other musculoskeletal disorders (MSDs), in the workplace. People can be helped to remain in work or helped to make an earlier return to work.
Advice for employers
Advice to help you to comply with your legal requirements and minimise the risk to your employees of developing back pain or making existing back pain worse. More on advice for employers. 
Advice for workers
Advice to help you to understand the causes of back pain and give advice on what to do if you are a sufferer. Advice for workers. 
Advice for health professionals
Advice for health professionals who manage patients with acute and chronic back pain. Advice for health professionals. 
Living with back pain
Most back pain is not caused by any serious damage or disease. The pain usually improves within a few weeks, at least enough to allow you to get on with your life. More about living with back pain.