What is Complex Regional Pain Syndrome (CRPS)?

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From the Guidelines

Complex Regional Pain Syndrome (CRPS) is a chronic pain condition characterized by excruciating pain, usually following an injury, and is often accompanied by changes in skin color, temperature, and swelling in the affected limb. This condition can be described as sympathetically maintained pain, causalgia, or reflex sympathetic dystrophy (RSD), and its prevalence is not well understood, although it has been reported in patients living with HIV 1. The pain associated with CRPS can gradually increase in intensity and size, sometimes spreading to the contralateral limb, and is proposed to be related to sympathetic dysregulation 1.

Key Characteristics of CRPS

  • Intense, burning pain that is disproportionate to the original injury
  • Changes in skin color, temperature, and swelling in the affected area
  • Hair loss, tissue changes, and skin discoloration at the site of the pain
  • Sympathetic dysregulation is proposed to play a role in the development of CRPS 1
  • CRPS can be associated with significant emotional distress and functional limitations, impacting quality of life

Treatment Approach

Treatment of CRPS usually requires a multidisciplinary approach, including:

  • Medications such as anticonvulsants, antidepressants, and sometimes opioids
  • Physical therapy to maintain movement
  • Sympathetic nerve blocks
  • Spinal cord stimulation
  • Psychological support Early diagnosis and treatment are crucial for better outcomes, as CRPS can become more difficult to treat over time 1. While some patients experience improvement or remission, others may have persistent symptoms requiring ongoing management.

From the Research

Definition and Characteristics of Complex Regional Pain Syndrome

  • Complex regional pain syndrome (CRPS) is a debilitating pain condition that often requires a multidisciplinary approach to restore the patient's quality of life 2
  • CRPS is characterized by spontaneous or stimulus-induced pain that is disproportional to the inciting event and accompanied by autonomic and motor disturbances 3
  • The syndrome is distinguished into two types: CRPS-I (without a nerve injury) and CRPS-II (with a nerve injury) 3, 4

Clinical Features and Pathophysiology

  • CRPS is a perplexing painful syndrome of the extremities, usually following a harmful event, with the upper limb being the most commonly affected extremity 5
  • The clinical picture unfolds across several domains: sensory, motor, autonomic, and trophic, with pain being the dominating feature 5
  • The pathophysiology of CRPS is still obscure, but it likely involves inflammation mediated by cytokines and neuropeptides, changes in the autonomic and central nervous system, psychological mechanisms, and autoimmunity 3, 5, 4

Diagnosis and Treatment

  • There are no established imaging or laboratory tests for the diagnosis of CRPS, and recently proposed diagnostic criteria have not yet been validated 3, 5
  • Treatment modalities include medication, physical therapy, occupational therapy, psychological therapy, and interventional procedures, with sympathetic nerve blocks being a first-line interventional treatment option 2
  • Other effective treatments may include bisphosphonates, glucocorticoids, vasoactive mediators, and spinal cord stimulation, as well as physical and occupational therapies such as mirror therapy and graded motor imagery 5, 4

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Interventional Modalities to Treat Complex Regional Pain Syndrome.

Current pain and headache reports, 2021

Research

Complex Regional Pain Syndrome: An update.

Mediterranean journal of rheumatology, 2019

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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