About 10 percent of the time, after [a] patient has recovered … pain persists. It persists for months and oftentimes for years, and when that happens, it is its own disease.

Source: "The Mystery of Chronic Pain." TED2011. Mar. 2011. Conference Presentation. Additional Information: This quote by pediatric anesthesiologist Elliot Krane is from his 2011 TED Talk which explains the bodily processes related to the oft-misunderstood phenomenon of chronic pain. The quote means that in some cases of injury or illness resulting in pain, even after the measurable causes of pain have subsided, the patient continues to experience pain. In such cases, the diagnosis becomes "chronic pain," which is a different condition from the injury or disease that the patient initially had. Though the causes behind chronic pain are not well understood, explains Krane, the condition seems to be related to nervous system feedback loops. Watch the full TED Talk here: Elliot Krane - The Mystery of Chronic Pain