Confusing and Substantially Overinterpreted

Letters to the Editor Modern Principles of Diagnosis and Treatment in Complex Regional Pain Syndrome by Alexandra Melf-Marzi, Dr. med. Bettina Böhringer, Dr. med. Matthias Wiehle, and Prof. Dr. med. Constanze Hausteiner-Wiehle in issue 51–52/2022

While a CME article about the difficult pathology of complex regional pain syndrome (CRPS) is very welcome, the mixture of long disproved theories regarding the pathogenesis and symptoms and confirmed factors is a source of irritation (1). Several statements, especially regarding the diagnosis, but also the treatment wrongly imply the possibility of a purely psychogenic origin. Stressful life events without a tissue injury do not trigger CRPS, whose initial symptoms can be explained with an imbalance of pro-inflammatory and anti-inflammatory cytokines (2). Regardless of this, psychological factors can have an unfavorable effects on the disease course, but they cannot trigger it. Furthermore, the differential diagnosis regarding psychiatric disorders can be difficult for colleagues who do not have any experience of the disorder. The objectifiable clinical findings stipulated in the clinical diagnostic criteria are, however, clearly labelled/named—where these are not present, no CRPS can be diagnosed (3). In findings that are difficult to objectify or discrepant , differential diagnoses have to be considered (for example, regarding a functional disorder) (4). Some of the examination findings shown in Box 3—such as the tendency to generalize and other non-specific behavioral changes—were over-interpreted by the authors. Even if CRPS can “jump across” to other limbs, the Budapest criteria that are obligatory for making a diagnosis also have to apply separately for each individual limb (2).

Even though the authors pointed out the selective literature search it is of note that many statements in the article are based on case reports and provide a somewhat one-sided perspective. Furthermore, some statements are not presented in the citations in the form that the authors referred to. This kind of CME presentation is not helpful in the context of the difficult diagnosis, therapy, and often required assessment of CRPS.

DOI: 10.3238/arztebl.m2023.0063

Prof. Dr. med. Elena Enax-Krumova, Prof. Dr. med. Martin Tegenthoff

Neurologische Klinik, BG Universitätsklinikum Bergmannsheil,
Ruhr-Universität Bochum

Prof. Dr. med. Elena Enax-Krumova

Mitglied der Klinischen Kommission „Schmerz“ der Deutschen Gesellschaft
für Neurologie

Dr. Dr. Andreas Schwarzer

Abteilung für Schmerzmedizin, BG Universitätsklinikum Bergmannsheil,
Ruhr-Universität Bochum

Prof. Dr. med. Martin Tegenthoff

Präsident der Deutschen Gesellschaft für Neurowissenschaftliche
Begutachtung

Prof. Dr. med. Christian Maihöfner, Prof. Dr. med. Heidrun H. Krämer

Sprecher und Sprecherin der Klinischen Kommission „Schmerz“ der
Deutschen Gesellschaft für Neurologie

Prof. Dr. med. Christian Maihöfner

Klinik für Neurologie, Klinikum Fürth

Mitglied im Ständigen Beirat der Deutschen Schmerzgesellschaft

Prof. Dr. med. Heidrun H. Krämer

Klinik für Neurologie, Universitätsklinikum Gießen

On behalf of the authors:

Prof. Dr. med. Janne Gierthmühlen

Interdisziplinäre Schmerz- und Palliativambulanz,
Klinik für Anästhesiologie und Operative Intensivmedizin,
Universitätsklinikum Schleswig-Holstein, Campus Kiel

Präsidentin der CRPS-Special Interest Group der
Internationalen Schmerzgesellschaft (IASP)

Conflict of interest statement

CM received lecture honoraria from Grünenthal.

The remaining authors declare that no conflict of interest exists.

References

1. Melf-Marzi A, Böhringer B, Wiehle M, Hausteiner-Wiehle C: Modern principles of diagnosis and treatment in complex regional pain syndrome. Dtsch Arztebl Int 2022; 119: 879–86

2. Bharwani KD, Kersten AB, Stone AL, et al.: Denying the truth does not change the facts: a systematic analysis of pseudoscientific denial of complex regional pain syndrome. J Pain Res 2021; 14: 3359–76

3. Goebel A, Birklein F, Brunner F, et al.: The valencia consensus-based adaptation of the IASP complex regional pain syndrome diagnostic criteria. Pain 2021; 162: 2346–8

4. Enax-Krumova E, Tegenthoff M: Diagnosesicherung bei der Begutachtung des komplexen regionalen Schmerzsyndroms (CRPS). MedSach 2017; 05: 222.