WHAT IS CHRONIC PAIN?

When you strain your back or burn your arm, receptor cells send messages along your nerve pathways to your brain. This results in a feeling of pain, a signal from your body that you must tend to it; when you get better, the pain should subside. But for an estimated one in five American adults, pain remains a constant companion.

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Chronic pain is defined as pain that lasts at least three months, often persisting well after any original injury has resolved.

In some cases the pain comes on without a known cause. “Chronic pain is a physical and an emotional response not only to actual tissue damage but also to perceived tissue damage,” says Leena Mathew, M.D., a pain management specialist at Columbia University Medical Center.

Where it shows up