Comparison of subjective motor imagery abilities in CRPS compared to chronic limb pain and healthy controls: a cross sectional study

Complex Regional Pain Syndrome (CRPS) is a chronic pain syndrome that affects brain structure and function such as motor imagery. However it is not known whether CRPS patients have a subjective MI deficit. In this single-center observational study, 123 patients were recruited (CRPS = 40, chronic limb pain, CLP = 40 and healthy individuals = 43). Participants completed the Motor Imagery Questionnaire - Revised Second (MIQ-RS) once on each side to assess their subjective kinesthetic (KMI) and visual (VMI) MI abilities. MIQ-RS total score and KMI and VMI subscores were compared between groups and between healthy and painful sides. There was no difference between or within groups (p>0.05; 95% CI) for all scores. Bayesian analysis suggested moderate evidence that CRPS patients had the same MI abilities as healthy individuals for the KMI scores (BF01 > 3), and that CLP patients had the same subjective MI abilities as healthy participants for all scores. This approach allowed us to conclude that CRPS patients are probably not deficient in their MI abilities despite a possible lack of power, however motor imagery training appears to be effective in rehabilitation programs, but not to improve a deficit. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethics committee of Full Institution: French Research Commitee "Comite de Protection des Personnes Sud Mediterrannee IV" gave ethical approval for this work I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present work are contained in the manuscript