Nociceptive pain
Nociceptive pain is caused when special nerve endings called nociceptors are irritated. These receptors sense temperature (hot/cold), vibration, stretch, and chemicals released from damaged cells. Nociceptors are the nerves which sense and respond to parts of the body which suffer from damage. They signal tissue irritation, impending injury, or actual injury. When activated, they transmit pain signals (via the peripheral nerves as well as the spinal cord) to the brain.
Nociceptive pain is caused by damage to body tissue and usually described as a sharp, aching, or throbbing pain. This kind of pain can be due to benign pathology; or by tumors or cancer cells that are growing larger and crowding other body parts near the cancer site. Nociceptive pain may also be caused by cancer spreading to the bones, muscles, or joints, or that causes the blockage of an organ or blood vessels.
Examples of nociceptive pain include sprains, bone fractures, burns, bumps, bruises, inflammation (from an infection or arthritic disorder), obstructions, and myofascial pain (which may indicate abnormal muscle stresses). The pain is typically well localized, constant, and often with an aching or throbbing quality. The pain is usually time limited, meaning when the tissue damage heals, the pain typically resolves.
Nociceptive pain can be classified into two categories:
• Somatic – somatic pain is initiated by stimulation of nociceptors in ligaments, tendons, bones, blood vessels, fasciae and muscles, and is dull, aching, poorly localized pain .The term musculo-skeletal pain means somatic pain. Somatic pain is generally sharp and well localized – if you touch it or move the affected area the pain will worsen.
• Visceral – Visceral pain is the subtype of nociceptive pain that involves the internal organs. It is felt in the internal organs and main body cavities. The cavities are divided into the thorax (lungs and heart), abdomen (bowels, spleen, liver and kidneys), and the pelvis (ovaries, bladder, and the womb). The sensation of visceral pain is more likely to be a vague deep ache. It is commonly refers to some type of back pain.
