Below are recent papers that have been published with links for further information.
J Neuroimmune Pharmacol. 2012 Aug 25.
Cooper MS, Clark VP.
Complex Regional Pain Syndrome (CRPS) is associated with non-dermatomal patterns of pain, unusual movement disorders, and somatovisceral dysfunctions. These symptoms are viewed by some neurologists and psychiatrists as being psychogenic in origin. Recent evidence, however, suggests that an autoimmune attack on self-antigens found in the peripheral and central nervous system may underlie a number of CRPS symptoms. From both animal and human studies, evidence is accumulating that neuroinflammation can spread, either anterograde or retrograde, via axonal projections in the CNS, thereby establishing neuroinflammatory tracks and secondary neuroinflammatory foci within the neuraxis. These findings suggest that neuroinflammatory lesions, as well as their associated functional consequences, should be evaluated during the differential diagnosis of non-dermatomal pain presentations, atypical movement disorders, as well as other “medically unexplained symptoms”, which are often attributed to psychogenic illness.
J Neural Transm. 2011 Sep;118(9):1301-9. Epub 2011 Feb 18.
Spreading of complex regional pain syndrome: not a random process.
van Rijn MA, Marinus J, Putter H, Bosselaar SR, Moseley GL, van Hilten JJ.
Abstract | Full article – read here
Complex regional pain syndrome (CRPS) generally remains restricted to one limb but occasionally may spread to other limbs. Knowledge of the spreading pattern of CRPS may lead to hypotheses about underlying mechanisms but to date little is known about this process. The objective is to study patterns of spread of CRPS from a first to a second limb and the factors associated with this process. One hundred and eighty-five CRPS patients were retrospectively evaluated. Cox’s proportional hazards model was used to evaluate factors that influenced spread of CRPS symptoms. Eighty-nine patients exhibited CRPS in multiple limbs. In 72 patients spread from a first to a second limb occurred showing a contralateral pattern in 49%, ipsilateral pattern in 30% and diagonal pattern in 14%. A trauma preceded the onset in the second limb in 37, 44 and 91%, respectively. The hazard of spread of CRPS increased with the number of limbs affected. Compared to patients with CRPS in one limb, patients with CRPS in multiple limbs were on average 7 years younger and more often had movement disorders. In patients with CRPS in multiple limbs, spontaneous spread of symptoms generally follows a contralateral or ipsilateral pattern whereas diagonal spread is rare and generally preceded by a new trauma. Spread is associated with a younger age at onset and a more severely affected phenotype. We argue that processes in the spinal cord as well as supraspinal changes are responsible for spontaneous spread in CRPS.
Clin J Pain. 2012 Aug 21. [Epub ahead of print]
Graded Motor Imagery and the Impact on Pain Processing in a Case of CRPS – read here about graded motor imagery
Graded motor imagery (GMI) shows promising results for patients with complex regional pain syndrome (CRPS).
In a case with chronic unilateral CRPS type I, we applied GMI for 6 weeks and recorded clinical parameters and cerebral activation using functional magnetic resonance imaging (fMRI; pre-GMI, after each GMI block, and after 6 mo). Changes in fMRI activity were mapped during movement execution in areas associated with pain processing. A healthy participant served as a control for habituation effects.
Pain intensity decreased over the course of GMI, and relief was maintained at follow-up. fMRI during movement execution revealed marked changes in S1 and S2 (areas of discriminative pain processing), which seemed to be associated with pain reduction, but none in the anterior insula and the anterior cingulate cortex (areas of affective pain processing). After mental rotation training, the activation intensity of the posterior parietal cortex was reduced to one third.
Our case report develops a design capable of differentiating cerebral changes associated with behavioral therapy of CRPS type I study.
Arch Dis Child. 2012 Aug 1.
Complex regional pain syndrome following immunisation.
Richards S, Chalkiadis G, Lakshman R, Buttery JP, Crawford NW.
Complex regional pain syndrome type 1 (CRPS-1) is a clinical syndrome that affects one or more extremities and is characterised by persistent pain disproportionate to any inciting event, and at least one sign of autonomic dysfunction in the affected limb(s). The pathogenesis of this syndrome is poorly understood, but its onset is often precipitated by a physical injury, such as minor trauma, fracture, infection or a surgical procedure. In the literature, there are reports of CRPS-1 following immunisation with rubella and hepatitis B vaccines. Here we present a case series of CRPS-1 following immunisation in adolescents, with either diphtheria-tetanus-acellular pertussis (1 case), or human papillomavirus vaccines (4 cases). Enhanced awareness of this syndrome and its potential to occur following immunisation in the paediatric population is vital to the prompt and effective management of this condition