I know, it hurts and that’s all you care about, right? But knowing what kind of pain you have can go a long way to putting together the puzzle of why you have it in the first place. Some pain is quite simple. You hit your thumb with the hammer or your head came into contact with the cupboard door. But not all pain is that easy to solve. Some pain syndromes are made up of different types of pain and are a little more complex to treat. Let’s begin by looking at the different types of pain.
There are two main classifications of pain – Nociceptive and Non-Nociceptive pain:
Nociceptive pain occurs when there is stimulus to localized pain receptors. You hit your head on the cupboard door and the pain receptors where you bump your head let you know that it hurts.
Non-nociceptive pain arises in the central and peripheral nervous systems where pain receptors do not exist. This type of pain happens when nerve cells malfunction.
Nociceptive pain can be further divided into somatic and visceral pain. Somatic pain occurs when the skin, bones, joints, muscles, tendons and ligaments hurt on movement or even while stationary. Cuts, scrapes, sprains, breaks and muscle cramps characterize this type of pain. This pain can be very sharp on movement and return to an ache when the body part is stationary.
Visceral pain usually affects the internal organs of various body cavities. The thoracic cavity contains the heart and lungs; the abdominal cavity contains the liver, gall bladder, spleen, bowels and kidneys; and the pelvic cavity contains the uterus, ovaries and bladder. This type of pain can be quite vague and difficult to localize and is usually characterized by a deep ache. In acute impact injury, the pain can become quite sharp and internal bleeding can occur. The pain can translate to various parts of the back depending on where the painful organ is located.
Non-Nociceptive pain is further divided into Neuropathic Pain and Sympathetic Pain.
Neuropathic pain comes from within the nervous system, like a pinched nerve, or from the peripheral nervous system which is the nerves between the spinal cord and the tissues. It may also come from the central nervous system which is the nerves between the spinal cord and the brain.
There can be any number of causes for neuropathic pain including, multiple sclerosis, stroke, brain hemorrhage, nerve degeneration, nerve pressure, pinched nerve, trapped nerve, slipped or torn disc or a nerve infection such as shingles. When a nerve becomes damaged or injured it becomes unstable electrically and starts firing off signals at random, in a disorderly fashion. These signals are totally hypersensitive and inappropriate. There may be associated numbness, tingling, sensations of cold or hot, and weakness.
The tissue which the nerve is usually associated with may malfunction and not work congruently or consistently. The pain can follow the area to where the nerve would normally supply. The best example of this is sciatic nerve pain, emanating from a slipped disc at L5 that follows the nerve to the outside shin and down to the big toe. Some pain emanating from the spine can be accompanied by intense itching, as well as shooting, burning and shooting pain, which may or may not be accompanied by hypersensitivity.
The second type of non-nociceptive pain is sympathetic pain, usually caused by an overactive sympathetic, central or peripheral nervous system. The sympathetic nervous system controls the effectiveness of the peripheral nervous system as well as blood supply to the extremities in addition to sweating for temperature control.
The most common occurrence of this type of pain is from fractures and soft tissue injuries to the arms and legs. These types of injuries may lead to Complex Regional Pain Syndrome (CRPS). Like neuropathic pain there are no specific pain receptors involved and the development process may be similar to neuropathic pain.
This type of pain results in extreme hypersensitivity in the skin around the location of the injury and may radiate along the limb. It is thought that the original pain may be the result of injury to the small peripheral nerves near the trauma site, which then travels along the limb. There are malfunctions in localized temperature control and sweating. The pain in the limb is usually so great the person cannot use it. Over time, other conditions like muscle wasting, ligament contractures, joint freezing and osteoporosis may occur.