What is pain?
Pain is usually a protective mechanism that alerts your brain when damage has occurred to your body. Pain isn’t just a sensation, it has emotional effects too – making us feel upset or distressed.
What can cause pain?
Injury or damage to your body
For example damage to cartilage in osteoarthritis.
Chemicals produced by inflammation
Chemicals activate specialised nerve endings, which send pain signals via your spinal cord to your brain. This happens in rheumatoid arthritis, for example.
Damage to nerves or nerve endings
Damage to nerves can cause pain signals to be sent to your spinal cord without a specific stimulus like an injury, or in response to something that wouldn't normally hurt, such as gentle stroking of the skin.
This sometimes happens in complex regional pain syndrome (reflex sympathetic dystrophy) or in peripheral neuropathy (a common problem in diabetes).
Sometimes it's difficult to explain the exact cause of long-term (chronic) pain. This can make it difficult to treat effectively.
This type of pain can sometimes be felt all over the body (chronic widespread pain), for example fibromyalgia.
These conditions can be challenging for both you and your doctor. The fact that it's hard to explain where the pain is coming from doesn’t mean your pain is imaginary or psychological. However, psychological factors can affect the way in which your brain senses physical pain.