Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage.

Pain results from the interaction between three components of the nervous system: the peripheral nerves, spinal cord and brain. Pain messages are sent from the peripheral nerves to a section of the spinal cord called the dorsal horn. Messages are then sent to a section of the brain called the thalamus.

In recent years, the medical community has recognized that psychological factors play a role in pain. Under the gate control theory of pain developed in the 1960s, pain is “gated” or shaped by past experience.

Nociceptive pain occurs when nerve receptors that sense tissue damage are stimulated by an unpleasant sensation. Neuropathic pain is caused by damage to the peripheral or central nervous system. Acute pain is temporary, whereas chronic pain is persistent and long-lasting. Pain can be experienced in many body parts, such as the head, neck, back, chest, arms and legs.

Pain is caused by a wide variety of injuries, conditions and diseases. Conditions that cause chronic pain include arthritis, fibromyalgia, lupus, chronic fatigue syndrome and carpal tunnel syndrome. Acute pain may be caused by an injury, such as a broken bone.

After asking a patient to describe the pain, including its location, severity and duration, a physician may document the pain using a pain diagram or other pain assessment. A number of tests may be performed to diagnose an underlying condition, including blood tests, x-rays, CAT scan, MRI or electromyography.

The many options for pain management include:

• Lifestyle changes such as exercise and weight loss
  
  
• Medications including analgesics and anti-inflammatories
  
  
• Therapies such as physical therapy, manipulation therapy, occupational therapy and cognitive behavioral therapy
  
  
• Modalities such as heat therapy, cold therapy, water therapy or electrical therapy
  
  
• Complementary and alternative treatments such as acupuncture and biofeedback
  
  
• Injection therapy such as epidural injections, nerve blocks or facet joint injections
  
  
• Surgeries such as arthroscopy, arthroplasty, carpal tunnel release or spine surgery