Chronic pain can affect any part of the body—from the back and neck to the jaw and pelvic area—and sometimes involves a group of symptoms, or syndrome. Chronic pain and pain syndromes may result from: - Fibromyalgia syndrome - Reflex sympathetic dystrophy syndrome - Temporomandibular joint (TMJ) syndrome - Pelvic pain – Osteoarthritis – Gout - Other musculoskeletal and neurological conditions. Chronic pain and pain syndromes may result from injuries, overuse of joints, disease, neurological or orthopedic causes, and unknown causes.