Acute vs. Chronic
Pain can be categorized as acute or chronic.
Acute pain is pain of less than three months duration and is generally provoked by a specific disease or injury, is thought to serve a useful biologic purpose and is usually expected to be self-limited.
For further information regarding acute pain, see:
Chronic pain is defined as persistent or recurrent pain lasting longer than 3 months and may be considered a disease state because it outlasts the normal time of healing if associated with a disease or injury. Chronic pain is thought to serves no biologic purpose and have no recognizable end-point.
According to an Institute of Medicine report released in 2011, one in three Americans experiences chronic pain—more than the total number affected by heart disease, cancer, and diabetes combined. In Europe, the prevalence of chronic pain is 20-30%. Currently, the number of Americans with chronic pain has risen to more than 100 million, with 1.5 billion people affected worldwide. Pain is the most common complaint that drives patients to see a clinician.
Recent Center for Disease Control and Prevention (CDC) and National Center for Health Statistics (NCHS) data identifies substantial rates of pain from various causes and that most people in chronic pain have multiple sites of pain. For U.S. adults reporting pain, causes include:
- Low back pain (28.1%)
- Knee pain (19.5%)
- Neck pain (15.1%)
- Severe headache or migraine (16.1%)
- Shoulder pain (9.0%)
- Finger pain (7.6%)
- Hip pain (7.1%)
- Pain Anatomy and Physiology
- Pain Definitions and Terms
- Neurobiology of Pain
- Neuropathic (Nerve) Pain
- Visceral Pain
- Cold Weather & Pain
- Central Sensitization
- Reward Deficiency Syndrome (RDS)
- Reward Deficiency Syndrome (RDS) – Chronic Pain
- Reward Deficiency Syndrome (RDS) – Addiction
Opioids Overview (start here)
- Opioid Tolerance
- Opioid Withdrawal
- Opioid-Induced Hyperalgesia (OIH)
- Withdrawal-Induced Hyperalgesia
- Opioid Blockers for Emergency Treatment of Opioid Overdose
- Alcohol, Pain & Opioids
- Medications for Pain – Overview
- NSAIDs (Non-Steroid Anti-Inflammatory Drugs)
- Gabapentin (Neurontin) & Pregabalin (Lyrica)
- CAM Medications for Pain (Complementary and Alternative)
- NMDA Antagonists – coming soon
- Toll-Like Receptor (TLR-4) Antagonists
- Alpha-2 Adrenergic Agonists:
- Light Therapy
- Dry Mouth (Xerostomia)
- Links to ALL Marijuana Educational Pages
- Marijuana – Medical Use Introduction
- Medical Marijuana – Getting Started
- Medical Marijuana – Introductory Principles
- Cannabinoids and Opioids
Integrating the Management of Pain:
- Integrative & Complementary and Alternative Medicine (CAM)
- CAM Medications for Pain
- Diet & Pain – An Overview
- Diet & Fasting
- Nutrition and Pain
- Diet & Dopamine
- Dopamine Enhancement
Interventional Procedures for neck and LBP:
Surgical Management of Pain:
- Coordinating Post-Operative Pain Management with Surgeon or Dentist
- Surgical Pain, Post-Operative
- Considering Surgery?
- Failed Back Surgery
- Post-Mastectomy Pain
Managing Pain Associated with Specific Diagnoses:
- Acute Intermittent Porphyria
- Arthritis – CAM Treatment
- Dental Pain
- Diabetic Peripheral Neuropathy – see also: Neuropathic (Nerve) Pain
- Ehlers-Danlos Syndrome
- Fibromyalgia – Overview
- Fibromyalgia – CAM Treatment
- Headaches – CAM Treatment
- Headaches – Low CSF Volume
- Traumatic Brain Injury (TBI)
- Loin Pain Hematuria Syndrome (LPHS)
- Low Back Pain (LBP) – Overview
- LBP – Arachnoiditis
- LBP – Superior Cluneal Nerve Entrapment
- LBP – Disc Pain
- LBP – Facet Pain
- LBP – Failed Back Surgery Syndrome
- LBP – Myofascial Pain
- LBP – Sacroiliac (SI) Joint Pain
- LBP – Sciatica
- LBP – Spinal Stenosis
- Mast Cell Activation Disease (MCAD)
- Meralgia Paresthetica
- Morton’s Neuroma
- Myofascial Pain
see below for more diagnoses
Key to Links:
Grey text – handout
Red text – another page on this website
Blue text – journal publication
Introduction to Pertinent Concepts and Terms for Understanding Pain:
Pain is defined as:
“an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.”
The Experience of Pain
The experience of pain is multidimensional – it is not a simple, singular experience – and the most important first step in learning to “reduce pain” requires an understanding of this concept.
The pain experience is comprised of three components:
1. The Sensory Component of Pain
The sensory component of pain is what people primarily relate to when communicating their pain. It represents the severity of pain, the location of pain, the temporal experience or timing of pain as being constant or intermittent and the character of pain: sharp, stabbing, burning, aching, dull etc.
2. The Cognitve Component of Pain
The cognitive component of pain is the awareness of pain. Pain can demand one’s attention to the exclusion of all else or it may be a subtle background annoyance, never actually absent from thought but overlooked when one’s attention if focused elsewhere.
3. The Affective Component of Pain
The affective component of pain is the emotional experience, encompassing the moods, feelings and attitudes toward pain. The affective component reflects the suffering associated with pain and is influenced by the context and experience of the pain and one’s cultural background.
The Integrative Management of Pain
The reason it is vital to comprehend all of these components of pain in order to “gain control” over one’s pain, is that the modulation of the pain experience can – and should – include methods that address each of these three components. It is important to realize that the extent to which one suffers from their pain is not solely related to the intensity of the pain (sensory experience), but suffering can be significantly modified by addressing the cognitive and affective components. Indeed, “Pain is inevitable, Suffering is optional.”
The integrative pain management programs at Accurate Clinic, opioid or non-opioid based, emphasize approaches to all three components of pain. Unfortunately it is all too common for physicians and patients to focus only on reducing the sensory experience of pain. Methods to reduce the sensory experience of pain draw the most effort from most people, including the use of medications, supplements, injections and surgical procedures.
Some medications, for example opioids, reduce both the sensory intensity of pain as well as the affective component. Studies of post-operative pain management with opioids reveal that patients describe being satisfied with their level of pain because it does not bother them although they often still report ‘feeling’ pain. The ability of opioids to dissociate the emotional component of pain is not unique – cannabanoids in marijuana are also proposed to share this property.
Quick and Easy, But…
Reducing the sensory experience may require little effort beyond taking a pill which may result in a rapid response in minutes. But… it is generally the case that the medication or chemical approach to pain results in only transient benefits that do not provide sustained pain relief, requiring frequent repeat dosing indefinitely. It is important therefore to manage chronic pain by engaging methods to reduce the other components of the pain experience to ultimately eliminate, or at least reduce, the reliance on the chemical approach to chronic pain management.
In the section “Using the Mind“ many techniques are presented to reduce not just the intensity of pain but also to reduce the cognitive experience and affective suffering of pain.
Pathological Pain Terminology
- Paresthesias – numbness or tingling
- Dysesthesias – electric shock phenomenon
- Hyperesthesia – increased sensitivity to mild painful stimuli
- Hyperalgesia – increased sensitivity to normally painful stimuli
- Hyperpathia – pain produced by subthreshold stimuli
- Allodynia – pain produced by normally non-painful stimuli
- Phantom – pain perceived to arise from a body part that has been amputated
Chronic pain is inconsistently defined but is generally considered to be pain that persists beyond the normal course of healing, with a time frame usually defined as 3 months or longer.
Chronic Pain Syndrome
Chronic Pain Syndrome is chronic pain associated with signi!cant psychosocial dysfunction. The psychosocial problems may include depression, drug dependence, anxiety, and other manifestations including pain complaints that are out of proportion to the physical findings. Chronic pain syndrome is not synonymous with chronic pain.
Central pain is pain arising from a lesion in the central nervous system – such as thalamic pain following stroke – or deafferentation pain (stemming from loss or interruption of sensory nerve fiber transmissions.
Central Pain Syndrome
Central pain syndrome is defined by the National Institute of Neurological Disorders and Stroke (NINDS) as “a neurological condition caused by damage to or dysfunction of the central nervous system.” Central Pain Syndrome can occur as a result of stroke, multiple sclerosis, neoplasm, epilepsy, CNS trauma, or Parkinson’s disease. Patients with central pain syndrome may experience localized pain, burning, and/or numbness in speci!c parts of the body, or throughout the body.
Types of Pain
Because the preferred choices of treatment for pain are based at least in part on the type of pain, it is important to understand the different types of pain and how to distinguish one type from the other. The experience of pain is often a combination of different types and therefore the treatment of pain often benefits from the use of more than one appproach and/or type of pain medication.
The term “nociception” is defined as the sensation relating to activity induced by activation of the nociceptor (pain receptor) and nociceptive (pain) pathways arising from actual or threatened damage to tissue (i.n other words, the neural process of encoding noxious stimuli). The transformation of nociception into pain, and acute pain into chronic pain is complex and difficult to define.
Nociceptive pain is caused by activation of neural pathways in response to damaging or potentially damaging stimuli to body tissue such as occurs with chemical or mechanical trauma or burns. Nociceptive pain generally diminishes once the peripheral driving force is removed and tissue damage repaired.
Nociceptive pain is usually described as a dull, aching, or throbbing pain, sometimes sharp. Nociceptive pain is further divided into “visceral” pain, originating from the organs inside the body, and “somatic” pain, originating from muscles, bone and skin. Visceral pain is often vague, difficult to describe and hard to localize. Nocicptive pain is usually a symptom of a disease process. Nociceptive pain, either visceral or somatic, can also produce “referred pain (see below), defined as pain perceived as occurring in a region of the body topographically distinct from the region in which the actual source of pain is located. As the source of spinal referred pain lies in the somatic tissues of the lumbar spine, it is often called somatic referred pain. Somatic referred pain is generally perceived in regions that share the same segmental innervation as the source. Nociceptive and somatic referred pain do not involve injury or disease of nerves and/or nerve roots.
With respect to back or neck pain, nociceptive pain arises from noxious stimulation of structures in the vertebral column and/or its surrounding structures including the facet joints, ligaments and tendons, muscles and the surrounding fascia.
Neuropathic Pain (“Nerve Pain”)
“Neuropathic” or nerve pain is pain initiated or caused by a primary lesion or dysfunction in a nerve or in the nervous system or pain arising as a direct consequence of a lesion or disease affecting the nervous system. Nerve pain is usually perceived as burning, electric, shock-like, tingling or sharp and may start at one location and shoot, or “radiate” to another location (like sciatica). Neuropathic pain can be “peripheral,” (outside the central nervous system),” like carpal tunnel pain or “central,” originating in the spinal cord or brain. Neuropathic pain is often a disease process, not simply the symptom of one.
For more information:
Inflammatory Pain (“Arthritis”)
Inflammatory pain is increased pain sensitivity due to an inflammatory process associated with chemical mediators that lower the threshold of nociceptors that innervate the damaged and inflamed tissue; it is also associated with exaggerated responses to normal sensory inputs and persists until the wound is healed and the inflammation resolves.
The pain associated with arthritis is sometimes referred to as inflammatory pain due to the underlying component of inflammation contributing to the pain and disease process. While not strictly a separate type of pain, arthritis pain is often treated differently due to the focus on reducing inflammation thereby reducing the associated pain. Recent research however show us that the pain and disease process of arthritis also involves the underlying bone of the affected joint and there is a neuropathic component to the pain of arthritis. The use of neuropathic pain agents has been shown to be helpful in arthritis pain. Treating arthritis with NSAIDs offers both analgesic and inflammatory benefits although the dosage and duration of treatment may vary between the two (see: NSAIDs).
The pain associated with internal organs and tissues is referred to as “visceral” pain. It tends to be somewhat vague when attempting to localize where it arises and it is often perceived as dull, aching or cramping although it may be burning or sharp and stabbing. Visceral pain is often perceived in a different location than where the problem originates (see “referred pain,” below). For example, the pain associated with a heart attack is often perceived down the left (or right) arm.
Some common conditions associated with visceral pain include chronic pancreatitis, endometriosis, interstitial cystitis, chronic prostatitis, chronic pelvic pain and irritable bowel syndrome. Visceral pain is now believed to often be accompanied by a hypersensitivity to pain as well as associated with central sensitivity that leads to a spread of symptoms beyond the specific organs involved in the primary condition.
While visceral pain may respond well to NSAIDs, especially menstrual pain, the hypersensitivity to pain in these conditions may respond to neuropathic pain agents such as gabapentin (Neurontin), pregabalin (Lyrica) and tricyclic antidepressants such as amitriptyline (Elavil)..
“Referred” Pain (“shooting pains”)
Referred pain often makes establishing a diagnosis challenging. When the pain originates in one location but is perceived in, or travels to, another location it is termed “referred” pain. Referred pain arises from central nervous system processing of afferent activity (nerve impulses traveling to the spine or brain) in intact nerves; it is not considered nerve (or neuropathic) based pain. The mechanism of referred pain is believed to consist of convergence of inputs from two tissues onto the same spinal neuron, and projection of the resulting pain sensation into the wrong tissue (i.e. not the one where the injury is located).
Many people with chronic low back pain also experience “sciatica,” pain that originates in the low back and travels down one or both legs – a common example of referred pain.
The source of referred pain is often difficult to identify accurately. “Sciatica,” so named after the sciatic nerve, implying that pain traveling from the low back into the lower extremities is generated by compression or other pathology of the sciatic nerve. Unfortunatly, it is not so simple. Many tissues have the capacity to refer pain to a different location. Best known of the referred pains are the dermatomal patterns of pain generated from a specific nerve root in the lower back that give rise to specific patterns of pain from the low back to the great toe for example. This is a “true” sciatica, referred pain from the sciatic nerve.
Somatic Referred Pain
However, somatic tissues in the back including the facet joints in the spine, muscles and fascia (the tissue surrounding muscles) can also refer pain below the waist and/or to the lower extremities. This is called somatic referred pain. Somatic referred pain is generally perceived in regions that share the same segmental innervation as the source. Nociceptive and somatic referred pain do not involve injury or disease of nerves and/or nerve roots.
Neuropathic Referred Pain
Referred nerve pain is likely to be perceived as typical neuropathic pain: burning, electric, tingling and usually well localized. Referred pain from the facet joints is more likely to be sharp or dull and aching and likely to be more vaguely localized, usually not below the knees. This case in point underscores the need to evaluate any pain carefully, especially referred pain, to establish an accurate diagnosis. If the diagnosis is wrong, the treatment is unlikely to be effective as many patients victimized by unsuccessful lumbar surgery for “sciatic” pain will attest to.
Identifying the Source of Pain
The greatest challenge to a physician can be establishing the source and cause of pain. While this web site is not how to diagnose pain, it is important to emphasize that there is no singular, reliable means of accurately diagnosing pain. Nothing is completely reliable, not an MRI, x-ray or other imaging, not the physical exam or laboratory testing and not obtaining a history. The answer, when it can be found, lies in integrating all available information to identify a pain. The responsibility of the patient is to assist by carefully providing their clinician with as much information as possible as to the nature of the pain, when it starts/stops, where it starts/stops, what makes it better/worse, how it feels (sharp, burning etc.) and any other additional information available. The patient and clinician working as a team will be much more effective in both diagnosing and treating pain.
To better understand how your clinician treats your pain and why specific medications or treatments may be advised,
please explore: Neurobiology of Pain.
Central Sensitization is a process of hyper-responsiveness to sensory stimuli which is a result of chronic pain-induced changes in the spinal cord and brain. It can be an important contributing process to the chronic pain experience.
For more information: Assessment and Management of Central Sensitization
Hyperalgesia is an exaggerated, increased painful response to a stimulus which is normally painful. Hyperalgesia can be a consequence of central sensitization and is also thought to occur with chronic exposure to opioids, although the clincal significance of this is uncertain.
For more information: Assessment and Management of Opioid Induced Hyperalgesia
Allodynia is a term that describes the experience of pain from a stimulus which does not normally provoke pain. Like hyperalgesia, allodynia can be a consequence of central sensitization. It commonly accompanies fibromyalgia and chronic headaches.
For more information: Assessment and Management of Central Sensitization
Additional Links to this Website and handout downloads:
Accurate Pain Management Program
- Program Information – for the patient
- Program Information – for the patient’s family
- Program Information – for the patient’s other physicians
Education Resources for Pain Clinicians and Pain Patients
- Academy of Integrative Pain Management (formerly American Academy of Pain Management)
- American Academy of Pain Medicine
General Pain Education Resources
- Academy of Integrative Pain Management (formerly American Academy of Pain Management)
- American Academy of Pain Medicine
- American Chronic Pain Association
- American Pain Foundation
- National Pain Foundation
- Taking Charge of Your Pain – Back in Control
- Global Pain Initiative
Couching for Pain Management
Support Groups for Pain Management
Patient Management – Overview
- Providing chronic pain management in the “Fifth Vital Sign” Era – Historical and treatment perspectives on a modern-day medical dilemma – 2017
- Pharmacological Management of Adults with Chronic Non-Cancer Pain in General Practice – 2020
Patient Education – Pain
- How to explain central sensitization to patients with ‘unexplained’ chronic musculoskeletal pain – Practice guidelines – 2011
- The efficacy of pain neuroscience education on musculoskeletal pain A systematic review of the literature – 2016
- Retention of pain neuroscience knowledge – a multi-centre trial – 2016
- Pain as a disease – an overview – 2017
- Visceral Pain – The Neurophysiological Mechanism – 2009
- What is different about spinal pain? – 2012
Relieving Pain in America: A Blueprint for Transforming Prevention, Care, Education, and Research (Free PDF book)
Pain – Diagnoses
- Headaches – CAM
- Migraine Triggers – handout
- Aneurysms – A Patient Guide to Recovery
- A Comprehensive Review of Central Post-Stroke Pain – 2015
- Central Post-stroke Pain and Pharmacological Treatment – Work in Progress – 2015
- Bisphosphonate therapy for osteogenesis imperfecta. – PubMed – NCBI
- Decrease in outpatient department visits and operative interventions due to bisphosphonates in children with osteogenesis imperfecta – 2011
- Bisphosphonates and their influence on fracture healing: a systematic review. – PubMed – NCBI
- Comprehensive therapy in osteoporosis using a single drug: from ADF… – PubMed – NCBI
- Effect of osteoporosis medications on fracture healing. – PubMed – NCBI
- Evaluation and Management of Vertebral Compression Fractures – 2012
- HOW DO BISPHOSPHONATES AFFECT FRACTURE HEALING? – 2017
- Treatment of Low Bone Density or Osteoporosis to Prevent Fractures in Men and Women – A Clinical Practice Guideline Update From the American College of Physicians – 2017
- Treatment of primary osteoporosis in men
Muscle Pain (Myofascial Pain) and Trigger Points
Diabetic Neuropathy (see Neuropathic Pain)
Burning Mouth Syndrome
Pain – Treatment
Planning Pain Management for Upcoming Surgery
- Massage – Types of Massage Therapy – handout
- Muscle Release – handout
Pain – Genetics
Genetic Testing in Private Practice
Publications co-authored by Eric Ehlenberger MD:
Opioid Addiction/Abuse Risk
Pain – Diet & Supplements
Emphasis on Education
Accurate Clinic promotes patient education as the foundation of it’s medical care. In Dr. Ehlenberger’s integrative approach to patient care, including conventional and complementary and alternative medical (CAM) treatments, he may encourage or provide advice about the use of supplements. However, the specifics of choice of supplement, dosing and duration of treatment should be individualized through discussion with Dr. Ehlenberger. The following information and reference articles are presented to provide the reader with some of the latest research to facilitate evidence-based, informed decisions regarding the use of conventional as well as CAM treatments.
For medical-legal reasons, access to these links is limited to patients enrolled in an Accurate Clinic medical program.
Should you wish more information regarding any of the subjects listed – or not listed – here, please contact Dr. Ehlenberger. He has literally thousands of published articles to share on hundreds of topics associated with pain management, weight loss, nutrition, addiction recovery and emergency medicine. It would take years for you to read them, as it did him.
For more information, please contact Accurate Clinic.
Supplements recommended by Dr. Ehlenberger may be purchased commercially online or at Accurate Clinic.
Please read about our statement regarding the sale of products recommended by Dr. Ehlenberger.
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