Alex Simotas, MD

Hospital for Special Surgery
Board Certified Physiatrist
Specializing In Spine & Sports Medicine

Home > Learning Center > Understanding Pain > Different Faces Of Pain

Different Faces Of Pain

Are there really different kinds of pain? The explosion of discovery in the field of neuroscience is rapidly transforming modern medicine. A big part of this change is the understanding of pain, its causes, and how it should be treated. Here is a list of commonly used terms:
    • Acute pain
    • Chronic pain
    • Sciatic pain
    • Neuropathic pain

Lets review what they mean, how they might be used in different scenarios, and if there is a real difference. The terms are old, but meanings and usage has changed as our understanding of pain has changed. The reality is that most of these distinctions are artificial and maybe even misleading.

Keep in mind the following:

  • The name doesn’t tell you the cause of the pain.
  • The terms are really only descriptive and meant to convey how and where you experience the pain.
  • More recent ideas of the causes of pain suggest that often these labels can be misleading. (See the article: The Painful Truth: The Pain and Spine Systems.)



Chronic simply means you have had it for more than 3 to 6 months and during this time pain occurs on average at least one out of every two days.

  • Acute: less than 3 to 6 months
  • Chronic: more than 3 to 6 months


Pain with no injury present or where any injury has already healed, is sometimes called chronic pain. A better term to be used in this instance is nonstructural pain. (see below). The idea here is that pain has little relationship to damage and exists with no beneficial function.

EPISODIC PAIN: Pain Often Occurs In Periodic Episodes:

  • Episodic pain: pain that lasts for days to weeks but then goes away.
  • Episodic exacerbations: periods of pain worsening that occur on top of a long history of chronic pain. While someone may have only a mild degree of pain everyday that never seems to go away, he or she also experiences periods of sharp worsening.

Other problems with the term CHRONIC PAIN:

  • For many potential reasons chronic pain is often more difficult treat than acute pain.
  • Treatments are often less effective on patients with chronic pain problems than those with acute pain.
  • As a result most patients and clinicians alike are reluctant to label problems as chronic pain. (Even though this term only indicates longevity.)

Considerations about CHRONIC PAIN:

  • The decision to define acute pain turning into chronic at 3 months is quite arbitrary.
  • One basic truth is that all chronic pain started, at some point in time, as acute pain (the first 3 to 6 months).


  1. Chronic pain will never go away and really cannot be cured.
  2. The only window of opportunity to cure pain is while it is still acute, in the first three to six months.
  3. Chronic pain exists only in the head, brain, or the spinal cord.
  4. Acute pain is specifically a problem “in the body” and not in the head, or nervous system.
  5. Chronic and acute pains are completely different types of problems that are caused by completely different factors.



The term structural is meant to relay that pain:

  • Is proportional or is strongly determined by tissue injury severity.
  • Is an indicator of harm or injury
  • Usually can localized to specific areas of musculoskeletal injury or inflammation.
  • Can still result in a varied patient experience because of additional factors.

Whereas the term Nonstructural pain:

  • Has a poor correlation to ongoing tissue injury.
  • Serves no functional purpose.
  • Is not an indicator of harm or injury.

Terms nonstructural and chronic are not synonymous. Chronic pain really only should be used to identify how long a pain problem has been present.



As it turns out, the longer a pain experience continues the more liable that nonstructural sources and influences control the pain problem. These influences include a lack of exercise (physical deconditioning), a person’s thoughts about the pain, as well as emotional states such as depression and anxiety.


Mostly this refers to a specific anatomic location in the musculoskeletal system that is causing the pain disturbance. This is an important feature of diagnosis and treatment. Knowing the areas of potential injury or pain sensitivity can be crucial in effective treatment.

On the other hand, pain often has multiple causes, influences, and mechanisms, so the idea of trying to call one specific spot in the body a pain generator can be misleading. Many studies suggest that a in a majority of cases of back pain, no specific injury can be identified. True or not, localization of specific areas of tissue injury or malfunction is an important part of diagnosis and treatment.


Back pain and sciatic pain are usually terms used for spine related symptoms.

Back Pain:

• If pain occurs mostly trunk, (spine), and buttocks region.

Sciatic Pain:

• If pain symptoms occur in the buttock, thigh, or leg and seem to emanate from the spine.


Neuropathic pain means pain from a disease in the nervous system as opposed to the rest of the body.

Neuro from the Greek nevro, or nerve; pathia, or disease.

Neuropathic pain is used for instances where nerves themselves are diseased and producing pain signals. Some common examples are:

  • Diabetic peripheral neuropathy
  • Post herpetic neuralgia
  • Multiple sclerosis
  • Lyme disease neuropathy

Neuropathic pain often responds to different treatment options than types of pain.

Treatments that appear effective:

  • Anti-convulsants: i.e. gabapentin (Neurontin), pregabalin (Lyrica)
  • Anti-depressants: Cymbalta, Effexor, Pamelor, Elavil
  • Nerve block injections

Treatments not as effective:

• Opioids (such as morphine)
• NSAIDs (such as ibuprofen, COX-2 inhibitors)