What are the diagnostic criteria for Chronic Pain Syndrome (CPS)?

Diagnostic Criteria for Chronic Pain Syndrome

Chronic Pain Syndrome (CPS) is defined as pain of any etiology not directly related to neoplastic involvement, associated with a chronic medical condition or extending in duration beyond the expected temporal boundary of tissue injury and normal healing, and adversely affecting the function or well-being of the individual. 1

Core Diagnostic Components

Duration Criteria

• Pain persisting for more than 3 months 2
• Pain extending beyond the expected temporal boundary of tissue healing 1

Functional Impact Assessment

• Significant emotional distress and/or functional disability 2
• Adverse effects on physical functioning, psychosocial well-being, and quality of life 1
• Impaired ability to perform activities of daily living 1

Pain Characteristics Evaluation

• Detailed pain history including onset, quality, intensity, distribution, duration, and course 1
• Assessment of sensory and affective components of pain 1
• Documentation of exacerbating and relieving factors 1
• Evaluation of associated symptoms (e.g., motor, sensory, and autonomic changes) 1

Comprehensive Assessment Requirements

Medical History Components

• Review of available medical records 1
• Complete medical and surgical history 1
• Social history, including substance use patterns 1
• Family history of pain conditions 1
• History of allergies 1
• Current medications including use patterns 1
• Review of systems 1

Physical Examination Elements

• Appropriately directed neurological examination 1
• Musculoskeletal evaluation 1
• Assessment of other body systems as indicated by symptoms 1
• Evaluation for asymmetric findings, sensory disturbances, and musculoskeletal changes 3

Psychosocial Evaluation

• Assessment of psychological symptoms (anxiety, depression, anger) 1
• Evaluation of psychiatric disorders 1
• Assessment of personality traits and coping mechanisms 1
• Evaluation of sleep patterns 1
• Assessment for addictive or aberrant behaviors 1
• Evaluation of interpersonal relationships 1
• Documentation of family, vocational, or legal issues 1
• Assessment of patient expectations and beliefs about pain 1

Diagnostic Testing Considerations

Imaging and Diagnostic Procedures

• Diagnostic testing only if indicated by specific clinical findings 1
• Imaging only when severe or progressive neurologic deficits are present 1
• Diagnostic testing when serious underlying conditions are suspected 1
• Pain specialty consultation for complex pain syndromes 1

Pain Mechanism Classification

• Categorization as neuropathic (e.g., diabetic neuropathy, postherpetic neuralgia, fibromyalgia) 1
• Categorization as nociceptive (e.g., osteoarthritis, muscular back pain) 1
• Identification of mixed pain mechanisms when present 1

Exclusion Criteria

• Pain is better accounted for by another specific condition 2
• Pain directly related to neoplastic involvement 1
• Pain better explained as a symptom secondary to an underlying disease (chronic secondary pain) 2

Special Considerations for Specific Pain Syndromes

Fibromyalgia Criteria

• Chronic widespread pain of at least 3 months' duration 4
• Poor sleep and/or fatigue 4
• Multiple somatic symptoms 4
• No diagnostic laboratory test; diagnosis based on clinical criteria 4

Complex Regional Pain Syndrome (CRPS)

• For chronic CRPS: fulfillment of Budapest Criteria for at least 12 months 3
• Asymmetric limb findings 3
• Sensory disturbances and musculoskeletal changes 3
• Optional diagnostic testing may include intraepidermal nerve fiber density assessment and imaging evidence of regional bone demineralization 3

Clinical Pitfalls and Caveats

• Failure to recognize CPS as a psychologic-physiologic disability may lead to ineffective treatment 5
• Treating chronic pain syndrome as an acute problem often leads to unsuccessful outcomes 5
• Lack of a diagnosis can significantly impact sufferers' daily lives 1
• Overreliance on diagnostic testing without appropriate clinical correlation may lead to unnecessary procedures 1
• Failure to distinguish between acute and chronic pain can result in inappropriate management strategies 5, 3