Chronic Pain

Pain persisting or recurring beyond normal tissue healing time, generally defined as >3 months.

Encompassing chronic primary pain (fibromyalgia, chronic primary headache: pain itself is the primary condition, disproportionate to identifiable tissue damage) and chronic secondary pain (ongoing pain from an identifiable underlying condition: chronic secondary musculoskeletal, cancer, post-surgical/post-traumatic, neuropathic, visceral).

Involves peripheral and central sensitization, altered pain processing, and significant psychosocial dimensions.

• Persistent pain, variable character (aching, burning, shooting), often with functional impairment, sleep disturbance, fatigue, mood impact (anxiety, depression: bidirectional relationship with pain), reduced quality of life.

• Central sensitization features: allodynia (pain from normally non-painful stimuli), hyperalgesia (exaggerated pain response), widespread pain beyond original injury site.

• Full history: pain characteristics, functional impact, psychosocial factors, prior treatments/response, red flags for underlying serious pathology requiring specific workup.

• Physical examination: identify contributing musculoskeletal/neurological findings.

• Investigations: targeted to underlying suspected cause, avoid excessive/repeated imaging without new indication (reinforces pain-focused illness behavior without benefit).

• Screen for depression/anxiety (bidirectional with chronic pain).

Differentials: identify treatable underlying cause where present (this is not "chronic pain" management until reversible/treatable causes addressed) inflammatory arthritis, malignancy, ongoing structural pathology, neuropathic causes.

Biopsychosocial approach: pharmacology alone rarely sufficient for chronic pain:

• Patient education: pain neuroscience education (understanding central sensitization reduces fear/catastrophizing, improves outcomes)

• Physical therapy/graded exercise: maintains function, reduces disability, strong evidence across chronic pain conditions; start low, progress gradually (avoid boom-bust cycling)

• Psychological therapies: CBT, acceptance and commitment therapy (ACT) address pain-related thoughts/behaviors, improve coping, strong evidence base

• Pharmacological (adjunctive, not sole strategy):

  • Neuropathic pain component: gabapentin/pregabalin, duloxetine, amitriptyline

  • Avoid long-term opioids for chronic non-cancer pain; evidence shows limited long-term benefit, significant harm (dependence, hyperalgesia, overdose risk); if trialed, time-limited with clear functional goals and regular review

  • NSAIDs: limited role long-term given GI/renal/cardiovascular risk with chronic use

  • Topical agents: capsaicin, lidocaine patches for localized neuropathic pain

• Multidisciplinary pain management programs: combined physical/psychological/pharmacological approach, strongest evidence for complex chronic pain

• Interventional options (per specific pain generator): nerve blocks, radiofrequency ablation, spinal cord stimulation; specialist pain medicine

• Sleep optimization: bidirectional relationship between poor sleep and pain severity

• Address comorbid depression/anxiety concurrently

Referral: pain management specialist for complex/refractory chronic pain, multidisciplinary program candidacy; psychology/psychiatry for significant comorbid mood disorder; specific specialty per underlying secondary cause.