Back pain, particularly low back pain is the most common musculoskeletal condition for which patients present to their doctors. It can be caused by mechanical or non-mechanical conditions and comes in two forms: complicated and uncomplicated. Mechanical back pain is associated with joints, connective tissue, nerves and discs. Non-mechanical back pain can be associated with visceral disease, tumors, cancer and infection. Complicated back pain includes sciatica which is leg pain that can be accompanied with numbness and weakness. This is usually associated with a disc herniation. Uncomplicated low back pain does not include sciatica and is usually related to joint, muscle or tendon inflammation. Although, it can be cause by an inflamed disc that has not yet herniated.