These authors contributed equally to this work.
Force modulation deficits in complex regional pain syndrome: A potential role for impaired sense of force production
Article first published online: 2 JAN 2014
© 2014 European Pain Federation - EFIC®
European Journal of Pain
Volume 18, Issue 7, pages 1013–1023, August 2014
How to Cite
Bank, P.J.M., van Rooijen, D.E., Marinus, J., Reilmann, R. and van Hilten, J.J. (2014), Force modulation deficits in complex regional pain syndrome: A potential role for impaired sense of force production. European Journal of Pain, 18: 1013–1023. doi: 10.1002/j.1532-2149.2013.00446.x
This work was supported by a grant from the Dutch Ministry of Economic Affairs [BSIK03016].
Conflicts of interest
Dr. Reilmann provided consulting services, advisory board functions, clinical trial services, quantitative motor analyses, and/or lectures for Novartis, Pfizer, Siena Bitoech, Neurosearch Inc., Ipsen, Teva, Lundbeck, Medivation, Wyeth, ISIS Pharma, Link Medicine, Prana Biotechnology, the Cure Huntington's Disease Initiative Foundation, MEDA, Temmler, AOP Orphan Pharmaceuticals AG. He serves on the Advisory Board of the ‘Jacques and Gloria Gossweiler Foundation’ and has several responsibilities in the European Huntington's Disease Network (member of the ‘executive committee’ and the ‘clinical trials task force’, lead facilitator of the ‘Neuroprotective Therapy’ and ‘Motor Phenotype’ working groups) and serves as Global Coordinating Principle Investigator of clinical trials. Dr. Reilmann received grant support from the High-Q-Foundation, the Cure Huntington's Disease Initiative Foundation (CHDI), the Deutsche Forschungsgemeinschaft (DFG), the European Union (EU-FP7 program) and the European Huntington's Disease Network (EHDN).
- Issue published online: 8 JUL 2014
- Article first published online: 2 JAN 2014
- Manuscript Accepted: 22 NOV 2013
- Dutch Ministry of Economic Affairs. Grant Number: BSIK03016
Compelling evidence points at both impaired proprioception and disturbed force control in patients with chronic complex regional pain syndrome (CRPS). Because force modulation at least partly relies on proprioception, we evaluated if impaired sense of force production contributes to disturbances of force control in patients with CRPS.
Characteristics of voluntary force modulation were examined in the affected upper extremity in 28 CRPS patients with abnormal postures, in 12 CRPS patients without abnormal postures, and in 32 healthy controls. Isometric grip-force matching was compared between conditions with and without visual feedback to identify potential deficits in the sense of force production in terms of force reproduction errors.
Voluntary force modulation was impaired in CRPS patients, but more so in patients with abnormal postures. In particular, CRPS patients with abnormal postures were characterized by reduced maximum force, reduced ability to increase force output according to task instructions, higher variability of force output and less adequate correction of deviations from the target force. Although effects of visual feedback removal appeared largely similar for the two patient groups and controls, our findings with respect to force reproduction errors suggested that an impaired sense of force production may contribute to the motor dysfunction in CRPS.
CRPS patients, in particular those with abnormal postures, showed impaired voluntary force control and an impaired sense of force production. This suggests that therapeutic strategies aimed at restoration of proprioceptive impairments, possibly using online visual feedback, may promote the recovery of motor function in CRPS.