What is Complex Regional Pain Syndrome (CRPS)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: June 16, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Complex Regional Pain Syndrome (CRPS) is a chronic pain condition characterized by excruciating pain, usually following an injury, and is described as being made worse by touch or stimulation, with sympathetic dysregulation proposed to play a role 1.

Key Characteristics of CRPS

  • Typically follows an injury, often minor
  • Described as excruciating and made worse by touch or stimulation
  • Pain gradually increases in intensity and size in the affected limb
  • Sometimes spreads to the contralateral limb
  • Associated with hair loss, tissue changes, and skin discoloration at the site of the pain

Diagnosis and Treatment

CRPS can be challenging to diagnose, and its exact cause remains unclear, but it appears to involve abnormal inflammation, immune system dysfunction, and changes in how the brain processes pain signals. Treatment typically involves a multidisciplinary approach, but there is limited information on the most effective treatment options for CRPS, especially in patients living with HIV 1.

Important Considerations

  • Little is known about the prevalence of CRPS, but it has been reported in patients living with HIV 1
  • CRPS does not have noticeable placebo analgesia, except at very early time points 1

From the Research

Definition and Characteristics of CRPS

  • Complex Regional Pain Syndrome (CRPS) is a chronic pain condition characterized by significant sensory, motor, and autonomic dysfunction, often following trauma or nerve injury 2.
  • It is historically known as causalgia and reflex sympathetic dystrophy, and manifests as severe, disproportionate pain, often accompanied by hyperalgesia, allodynia, trophic changes, and motor impairments 2.
  • CRPS is classified into type I (without nerve injury) and type II (associated with nerve damage) 2, 3.

Pathophysiology and Diagnosis

  • The pathophysiology of CRPS involves peripheral and central sensitization, neurogenic inflammation, maladaptive brain plasticity, and potential autoimmune and psychological influences 2.
  • The diagnosis relies primarily on clinical evaluation using criteria such as the Budapest Criteria, supported by supplementary tests to exclude differential diagnoses 2.
  • However, its overlapping features with other conditions complicate diagnostic accuracy 2, 4.

Treatment and Management

  • The management of CRPS necessitates a multidisciplinary approach combining physical therapy, psychological support, and pharmacotherapy 2, 5.
  • Physical therapies, including graded motor imagery and mirror therapy, are essential for preserving function and preventing complications 2, 3.
  • Pharmacological treatments target neuropathic pain and inflammatory components, utilizing agents such as gabapentinoids, corticosteroids, and bisphosphonates 2, 5.
  • In refractory cases, interventional modalities like spinal cord stimulation and dorsal root ganglia stimulation provide promising options, although their efficacy remains variable 2, 5.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

The complex regional pain syndrome.

Handbook of clinical neurology, 2015

Research

Complex regional pain syndrome in adults.

Rheumatology (Oxford, England), 2011

Research

Complex regional pain syndrome: a review.

Annals of vascular surgery, 2008

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.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.