Complex Regional Pain Syndrome: Practical Diagnostic and Treatment Guidelines

Key points

• Complex regional pain syndrome (CRPS) is diagnosed with the Budapest criteria, adopted by the International Association for the Study of Pain (IASP) in 2012.
• The Budapest criteria have a sensitivity of 0.99 and a specificity of 0.68, compared with a specificity of only 0.36 for the older 1994 criteria.
• The traditional three sequential stages of CRPS are not supported by evidence; warm and cold presentations are recognised informally and should be noted.
• Interdisciplinary treatment built around functional restoration of the affected limb is the core of management.
• Research on CRPS is generally of low to medium quality with small samples, because the condition is rare.

Overview

This fifth edition of practical guidelines for CRPS (also known as reflex sympathetic dystrophy or causalgia) was written by experts in each discipline involved in its treatment and sponsored by the Reflex Sympathetic Dystrophy Syndrome Association. The authors used a semi-systematic review supplemented by preliminary research and clinical experience, grading evidence from level 1 (meta-analyses and systematic reviews) to level 4 (case reports and clinical experience). The guidelines aim to support, not replace, clinical judgement, and treatment should be tailored to each patient. This overview covers diagnosis, severity assessment and rehabilitation; the guideline's sections on drug treatment, psychological and interventional therapies are not summarised here.

Diagnosis

CRPS is continuing regional pain that is disproportionate to any inciting event, usually with distal sensory, motor, sweating, vasomotor and/or trophic changes. Under the Budapest criteria, the patient must report at least one symptom in three of four categories (sensory, vasomotor, sudomotor/oedema and motor/trophic), show at least one sign at evaluation in two or more categories, and have no other diagnosis that better explains the findings. The criteria were designed as broad and accessible screening criteria, and they are being added to ICD-11. A new subtype, CRPS with remission of some features, covers patients who once met full criteria and still have symptoms needing care; temporarily not meeting the criteria does not mean cure. The distinction between CRPS type I and type II (with major nerve damage) is retained mainly for historical reasons.

Subtypes and severity

Cluster analyses do not support sequential stages. A large international study identified a warm subtype (warm, red, dry, swollen limb) and a cold subtype (cold, blue, sweaty, less swollen limb), with median CRPS duration of 4.7 and 20 months respectively and similar pain intensity. The CRPS Severity Score has 16 items (8 signs and 8 symptoms) scored 0–16; a change of 5 or more points reflects a clinically significant change. An international consortium (COMPACT) has agreed a core outcome data set and is building a clinical research registry.

Interdisciplinary management and rehabilitation

Management centres on functional restoration, following the Malibu algorithm: a gradual progression from motor imagery and gentle active movement to weight bearing, stress loading (scrubbing and carrying), desensitisation and oedema control, aiming at full return to work and daily life. Drugs, sympathetic blocks and psychotherapy are added when patients fail to progress, but are recommended from the outset when there are significant problems such as severe depression or anxiety or pain too severe to engage in therapy. A coordinated interdisciplinary team is preferred; a multidisciplinary approach led by one practitioner is the next best option. In a controlled study of 135 patients with upper limb CRPS, physical and occupational therapy helped manage pain, restore mobility and reduce impairment, and in 28 children exercise therapy reduced or eliminated pain in 92%. Graded motor imagery improved pain in a small trial of 13 patients, but larger follow-up studies failed to show benefit. Physical therapy should stay within the patient's tolerance and is not given when the limb is numb, for example right after a block; overly aggressive therapy, prolonged ice and inactivity can worsen CRPS, and contrast baths are not recommended in advanced cases.

Frequently asked questions

How is CRPS diagnosed?

With the Budapest criteria: disproportionate continuing pain, symptoms in at least three of four categories, signs in at least two categories at examination, and no better explanation for the findings.

Does CRPS progress through fixed stages?

No. Studies do not support the traditional sequential stages, although warm and cold presentations differ and should be recorded.

What is the main treatment approach?

Interdisciplinary functional restoration of the affected limb, with medicines, blocks and psychological support added as needed to help the patient progress.

Source

Harden RN, McCabe CS, Goebel A, Massey M, Suvar T, Grieve S, Bruehl S. Complex Regional Pain Syndrome: Practical Diagnostic and Treatment Guidelines, 5th Edition. Pain Med 2022;23(Suppl 1):S1-S53. DOI: 10.1093/pm/pnac046. Open access under a CC BY licence. Summary prepared by Medpresso from the original publication; it is not a substitute for the full text or for medical advice.