Chronic Pain – Symptom or Disease?

Pain: An Unmet Medical Need

• 1 in 8 people will experience unrelieved, persistent pain at some point in their lives

• Only 50% of patients with postoperative pain are satisfied with their pain treatment

• Chronic unrelieved pain leads to a morbid state with progressive physical and social dysfunction

• The two main categories of analgesics (opioids & NSAIDs) were developed over two centuries ago

What Is Pain?

Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.
(IASP definition, Subcommittee on Taxonomy, 1979)

Acute Pain

A biological symptom, an automatic response to a noxious stimulus, tissue injury, or trauma.
It is a multidimensional individual experience with multifactorial clinical presentation, influenced by tissue damage, emotional shifts, expectations, motivation, and psychological factors.

Chronic Pain

Chronic pain is considered a disease and is defined as pain lasting longer than the expected course of healing—typically beyond 3 to 6 months.
It is now widely accepted that the traditional biomedical model is inadequate for managing typical chronic pain (CP) patients.

Pain Models

• Biomedical – Focuses on causality and pathophysiology

• Psychogenic – Pain as a manifestation of psychological disorders

• Biopsychosocial – Integrates mechanical & physiological processes with psychological & social variables

Chronic pain is now understood as a biopsychosocial phenomenon, comprising sensory, emotional, and cognitive-evaluative components.

What Is Chronic Pain Syndrome (CPS)?

Persistent pain associated with:

• Progressive functional decline at home, work, and in society

• Increasing use of medications and medical interventions

• Mood disorders, anger, and hostility

Common Chronic Pain Syndromes

• Complex Regional Pain Syndrome (CRPS)

• Fibromyalgia

• Radiculopathy (chronic spinal pain)

• Piriformis Syndrome (chronic low back pain)

• Chronic Pelvic Pain

• Phantom Limb Pain

• Psychogenic Pain

Epidemiology of Chronic Pain

• Leads to disability

• Rising concern in healthcare, a major economic burden

• Affects 1/3 of the population

Bonica: Headaches are most frequent and disabling, but chronic low back pain (CLBP) incurs higher medical costs

Stewart et al.: 75% of productivity loss due to CP occurs while working, not from absenteeism

Chronic arthritis and musculoskeletal disorders:

• High disability risk

• By 2030, medically diagnosed arthritis and disability will affect 71 million Americans due to aging

Secondary CP (in >70% of patients with):

• Spinal cord injury, stroke, cerebral palsy, TBI, MS, amputation

  • 70–80% spinal cord injury

  • 67–85% amputation

  • 44–66% MS

Socioeconomic Impact of CP

• Hospitalization, lost wages, productivity losses, compensations, and disability benefits

• Annual cost of CP in the U.S.: $70–120 billion

  • 90 million medical visits

  • 14% of prescriptions

  • 50 million workdays lost

  • Total economic cost: ~$100 billion

Chronic Low Back Pain (CLBP) Epidemiology

• Lifetime prevalence: 60–90%

• Annual prevalence: 5%

• Annual cost: >$50 billion

• 10% of CLBP claims = 80% of total costs

• 1–2% of North American workforce files disability claims due to CLBP

• Germany (1998): €24 billion in disability claims, €10 billion in treatment

• Only 5–15% of acute LBP cases progress to chronic

• #1 cause of disability <45 years, #3 in >45 (after arthritis)

Chronic Pain: A Complex Condition

Chronic pain is multifaceted, with medical and psychosocial dimensions, requiring an interdisciplinary and comprehensive approach.
It can be as disabling as alcoholism, stroke, or spinal cord injury and must be treated accordingly.

Ideal Pain Clinic Model

• Interdisciplinary with a wide range of therapeutic techniques

• The Director provides overall clinical guidance

• The Coordinator manages daily patient care

Typical team includes:

• Physiatrist / Pain Specialist

• Clinical Psychologist

• Physiotherapist

• Occupational Therapist

• Vocational Counselor

• Social Worker

• Recreation Therapist

• Dietitian

• Rehabilitation Nurse

• Consulting Physicians (as needed)

Ideal candidates:

• Motivated CP patients

• No secondary gain

• Accept program goals

Clinical Evaluation

Patients with CPS may be labeled “chronic complainers.”
Thorough history and detailed physical exam are essential.

Medical History should focus on:

• Onset, duration, intensity, and location of pain

• Functional status before pain onset

• Reactions to prior interventions (predictors of treatment response)

• History of addiction or dependency

• Relationships, stressors, and possible secondary gain

• Response to previous medications

Waddell’s Yellow Flags
Beliefs & Attitudes

• Catastrophic thinking

• Passive attitude

• Belief that pain is harmful

Behaviors

• Poor sleep

• Activity avoidance

• Smoking, alcohol use

• Dramatic pain reports

Emotions

• Helplessness

• Hopelessness

• Fear of pain escalation

Family Response

• Overprotectiveness

• Lack of social support

Physical Exam

• Focus on neurological and musculoskeletal systems

• Includes Waddell’s non-organic signs:

  • Simulation, distraction, tenderness, overreaction, regional disturbances

Diagnostic Testing

Use tests selectively based on clinical findings.
Avoid unnecessary repetition of past tests.

Lab Tests

• Often normal unless underlying disease is present

Imaging

• X-rays, MRI, CT widely used due to non-invasive nature

Other Tests

• EMG, nerve conduction studies, bone scans, thermography (as needed)

Psychological Evaluation

Helpful when pain disrupts emotional, social, or occupational functioning.
Goals: identify emotional, cognitive, behavioral, and vocational factors influencing pain perception.

Patient Education is crucial to reduce resistance and misconceptions (e.g., “I’m not crazy”).

Tools used:

• McGill Pain Questionnaire

• Multidimensional Pain Inventory

• MMPI

• Symptom Checklist-90

• Beck Depression Inventory

• State-Trait Anxiety Inventory

Treatment

Goals

• Complete elimination of pain is often unrealistic

• Focus on breaking pain behavior cycle and improving quality of life

Key objectives:

• Reduce medication use

• Modify pain perception

• Increase physical activity

• Change behavior toward pain

• Reduce disability

• Improve quality of life

Behavioral Therapy

Focuses on retraining behavior toward pain through:

• Patient education

• Skill development

• Activity planning

• Cognitive-behavioral strategies

Pharmacotherapy

• CP patients often undertreated for acute and overmedicated for chronic pain

• Aim: Reduce or eliminate opioids, sedatives, and hypnotics

• May require detoxification in pain clinic setting

Pain Modification Techniques

Non-drug, adjunctive methods that:

• Can be used at home

• Encourage active participation

• Are time-limited

Examples:

1. TENS (Transcutaneous Electrical Nerve Stimulation)

2. Thermal Modalities (Heat/Cold)

3. Biofeedback (BFB)

4. Invasive Interventions: nerve blocks, facet joint injections, epidurals

5. Spinal Cord Stimulation

Increasing Physical Activity

Therapeutic exercise is critical for restoring function and physical condition.
Fear of movement leads to deconditioning: joint stiffness, reduced endurance, muscle atrophy.
Goal: restore musculoskeletal and cardiovascular health

Psychosocial Interventions

Combined with medical and physical therapies, they improve outcomes.

Includes:

• Psychotherapy

• Psychoeducation

• Biofeedback and relaxation training

• Vocational counseling

Conclusion

Patients with chronic pain are often challenging to manage.
A multidisciplinary pain clinic, based on comprehensive, team-based care, is the most effective model for assessment and rehabilitation.

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