Pain describes unpleasant  experiences that everyone would rather avoid. Pain demands attention and pain relief is a principle goal of medical therapeutics. Pain comes in different shapes and sizes and is not easy to define. No human escapes pain experiences and chronic pain is now the most prevalent human symptoms. Pain relievers are not always effective and usually have negative effects. 

Norman J. Marcus, M.D. stated that "we need to recognize that pain is an epidemic of sorts and that we are not adequately handling patients with pain."  Marcus estimated that headaches disrupt productivity in 40-million Americans each year, while back pain interferes with work in 36-million people, muscle pain affects 24-million people and neck pain affects 20-million people. For persistent pain in general, the cost estimates are around $100 billion per year.  The cost of back pain is estimated to be $16-20 billion per year. Marcus stated: "Back pain is a problem of fitness…if we made weight loss and exercise a national priority, the result would filter down in tremendous savings for our beleaguered health care system…Even something as simple as walking the equivalent of two miles per day could reduce utilization and cost of medical services."

Musculoskeletal and rheumatic complaints account for approximately 15% of the patients seen by primary care physicians. These complaints include muscle pain and weakness, regional pain syndrome such as back or neck pain, rheumatoid arthritis, gout, ankylosing spondylitis and lupus erythematosus.  More aggressive muscle pain associated with muscle inflammatory activity is less common and occurs in patients with the autoimmune disorders, polymyalgia rheumatica and polymyositis.

Generalized Aching and Stiffness

In many patients, pain, stiffness and loss of function occur without demonstrable inflammation. Their diagnoses include chronic low-back pain, fibrositis, fibromyalgia, fibromyositis, myofacial pain syndrome and idiopathic myalgia. The pain seems to originate from muscles and connective tissue with little or no evidence of tissue changes. Blood tests are normal, even when the disability from pain, weakness, and stiffness is severe. Aching is often associated with fatigue and other symptoms. Gastrointestinal Tract symptoms are especially common. Patients with these diagnoses are usually offered drugs by their physicians. Pain-relievers, NSAIDs, muscle relaxants, tranquilizers and anti-depressant drugs are all popular, but none are particularly helpful