Main Types of Chronic Pain

Nociceptive pain is pain detected in either the body's soft tissues (such as muscles and skin) or organs by specialized sensory nerves, known as nociceptors. Nociceptors detect painful stimuli, sending information to the spinal cord and brain for interpretation and response.

Nociceptive pain may be somatic or visceral in nature. 

Examples of nociceptive pain:

• Headaches
• Pelvic pain not caused by nerve damage
• Arthritis
• Fibromyalgia

Somatic pain is a type of nociceptive pain. Somatic pain refers to pain detected by sensory nerves in the muscles, skin and soft tissues.

When you experience somatic pain, nociceptors send pain messages to the spinal cord and brain for interpretation. This type of pain is often easy to locate, as sensory nerves are well-distributed throughout ​the soft tissue.

Examples of somatic pain include:

• Tension headaches
• Pelvic pain from joint instability
• Arthritis
• Bone fracture
• Back pain not caused by nerves

Visceral pain is also a type of nociceptive pain. Visceral pain refers to pain detected by nociceptors in the body's internal organs. Like somatic pain, visceral pain detected by sensory nerves is sent to the spinal cord and brain for interpretation.

Sensory nerves in the internal organs are not as widespread as they are in the body's muscles and skin. This can make visceral pain feel dull and hard to localize. Unlike somatic pain, visceral pain may be felt further away from its actual origin.

Some examples of visceral pain include:

• Endometriosis
• Irritable bowel syndrome
• Bladder pain (such as cystitis)
• Prostate pain

Neuropathic pain is also caused by nerves, but it is different from nociceptive pain in that the nerves are often not functioning "normally."

Neuropathic pain is caused by nerve disturbances and spontaneous transmission of pain signals to the spinal cord and brain. Neuropathic pain is often described as sharp, stabbing, shooting, burning, or electrical.

Some possible reasons for neuropathic pain include nerve irritation, nerve damage or the formation of a neuroma.

Examples of neuropathic pain include:

• Peripheral neuropathy (for example, diabetic neuropathy)
• Post-mastectomy pain
• Sciatica

Psychogenic pain is the term for pain caused by a psychological disorder, such as depression or anxiety. Many psychological disorders have physical complications, such as fatigue and muscle aches and pains. Because psychogenic pain does not usually have any physical origin, it is more difficult to treat than nociceptive or neuropathic pain.

Psychogenic pain is real, though it may require a different treatment approach than other physical types of pain. Non-pharmaceutical pain treatments, combined with antidepressants or other psychological medications, are often more effective than traditional painkillers. These include:

• TENS
• Distraction
• Relaxation
• Counseling

Idiopathic pain is pain that exists when there is no known physical or psychological cause. Idiopathic pain cannot be traced back to a nociceptive, neuropathic or psychogenic cause. While the cause of pain may not be detectable with current medical knowledge, it is still very real.

Idiopathic pain is more common in people who have a pre-existing pain disorder. These disorders include TMJ disorders and fibromyalgia.

Because its cause is not apparent, idiopathic pain is often difficult to treat.