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A barrier to dissemination of research is that it depends on the end-user searching for or 'pulling' relevant knowledge from the literature base. Social media instead 'pushes' relevant knowledge straight to the end-user, via blogs and sites such as Facebook and Twitter. That social media is very effective at improving dissemination seems well accepted, but, remarkably, there is no evidence to support this claim. We aimed to quantify the impact of social media release on views and downloads of articles in the clinical pain sciences. Sixteen PLOS ONE articles were blogged and released via Facebook, Twitter, LinkedIn and ResearchBlogging.org on one of two randomly selected dates. The other date served as a control. The primary outcomes were the rate of HTML views and PDF downloads of the article, over a seven-day period. The critical result was an increase in both outcome variables in the week after the blog post and social media release. The mean ± SD rate of HTML views in the week after the social media release was 18±18 per day, whereas the rate during the other three weeks was no more than 6±3 per day. The mean ± SD rate of PDF downloads in the week after the social media release was 4±4 per day, whereas the rate during the other three weeks was less than 1±1 per day (p<0.05 for all comparisons). However, none of the recognized measures of social media reach, engagement or virality related to either outcome variable, nor to citation count one year later (p>0.3 for all). We conclude that social media release of a research article in the clinical pain sciences increases the number of people who view or download that article, but conventional social media metrics are unrelated to the effect.

We wanted to find out whether people who suffer from dizziness take longer than people who do not, to perform a motor imagery task that involves implicit whole body rotation. Our prediction was that people in the "dizzy" group would take longer at a left/right neck rotation judgment task but not a left/right hand judgment task, because actually performing the former, but not the latter, would exacerbate their dizziness. Secondly, we predicted that when dizzy participants responded to neck rotation images, responses would be greatest when images were in the upside down orientation; an orientation with greatest dizzy-provoking potential. To test this idea, we used a case-control comparison design. One hundred and eighteen participants who suffered from dizziness and 118 age, gender, arm pain, and neck pain-matched controls took part in the study. Participants undertook two motor imagery tasks; a left/right neck rotation judgment task and a left/right hand judgment task. The tasks were completed using the Recognise program; an online reaction time task program. Images of neck rotation were shown in four different orientations; 0°, 90°, 180°, and 270°. Participants were asked to respond to each "neck" image identifying it as either "right neck rotation" or a "left neck rotation," or for hands, a right or a left hand. Results showed that participants in the "dizzy" group were slower than controls at both tasks (p = 0.015), but this was not related to task (p = 0.498). Similarly, "dizzy" participants were not proportionally worse at images of different orientations (p = 0.878). Our findings suggest impaired performance in dizzy people, an impairment that may be confined to motor imagery or may extend more generally.

Understanding motor imagery of the hands and feet has led to promising new treatments for neurological and chronic pain disorders. We aimed to extend this line of research to the neck with a view to developing the definitive platform study upon which clinical and experimental studies can be based. In a cross-sectional experiment with a convenience sample, volunteers were shown 40 photographs of a model with their head turned to the left or right. Images were presented in random order and orientation. Participants judged the direction of neck rotation. They also completed a left/right hand judgment task. 1361 pain-free participants volunteered. Mean ± standard deviation response time (RT) for making left/right judgments of neck rotation was 1.621 ± 0.501 s. Median accuracy was 92.5%. RT was related to age, gender, and handedness (p < 0.001). That is, RT increased with age, was greater in females than in males and was greater in left-handers than in right-handers. Accuracy reduced with age (p < 0.001), but was unaffected by gender or handedness. Judgments were more accurate when images showed a neck rotated to the right than when they showed a neck rotated to the left (p < 0.001). The magnitude of image rotation affected both response time and accuracy (p < 0.001). In general, the performance parameters established for left/right limb judgments also apply for left/right neck rotation judgments. The current work establishes the definitive normative values against which clinical and experimental groups can be compared and reveals unpredicted effects of the direction neck rotation and the orientation of the image., (Copyright © 2013. Published by Elsevier Ltd.)

Background: There is currently no strong consensus regarding the optimal management of complex regional pain syndrome although a multitude of interventions have been described and are commonly used., Objectives: To summarise the evidence from Cochrane and non-Cochrane systematic reviews of the effectiveness of any therapeutic intervention used to reduce pain, disability or both in adults with complex regional pain syndrome (CRPS)., Methods: We identified Cochrane reviews and non-Cochrane reviews through a systematic search of the following databases: Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (DARE), Ovid MEDLINE, Ovid EMBASE, CINAHL, LILACS and PEDro. We included non-Cochrane systematic reviews where they contained evidence not covered by identified Cochrane reviews. The methodological quality of reviews was assessed using the AMSTAR tool.We extracted data for the primary outcomes pain, disability and adverse events, and the secondary outcomes of quality of life, emotional well being and participants' ratings of satisfaction or improvement. Only evidence arising from randomised controlled trials was considered. We used the GRADE system to assess the quality of evidence., Main Results: We included six Cochrane reviews and 13 non-Cochrane systematic reviews. Cochrane reviews demonstrated better methodological quality than non-Cochrane reviews. Trials were typically small and the quality variable.There is moderate quality evidence that intravenous regional blockade with guanethidine is not effective in CRPS and that the procedure appears to be associated with the risk of significant adverse events.There is low quality evidence that bisphosphonates, calcitonin or a daily course of intravenous ketamine may be effective for pain when compared with placebo; graded motor imagery may be effective for pain and function when compared with usual care; and that mirror therapy may be effective for pain in post-stroke CRPS compared with a 'covered mirror' control. This evidence should be interpreted with caution. There is low quality evidence that local anaesthetic sympathetic blockade is not effective. Low quality evidence suggests that physiotherapy or occupational therapy are associated with small positive effects that are unlikely to be clinically important at one year follow up when compared with a social work passive attention control.For a wide range of other interventions, there is either no evidence or very low quality evidence available from which no conclusions should be drawn., Authors' Conclusions: There is a critical lack of high quality evidence for the effectiveness of most therapies for CRPS. Until further larger trials are undertaken, formulating an evidence-based approach to managing CRPS will remain difficult.

Objective: Graded motor imagery (GMI) shows promising results for patients with complex regional pain syndrome (CRPS)., Methods: 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., Results: 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., Discussion: Our case report develops a design capable of differentiating cerebral changes associated with behavioral therapy of CRPS type I study.

Crossing the hands over the midline impairs the ability to correctly judge the order of a pair of tactile stimuli, delivered in rapid succession, one to each hand. This impairment, termed crossed-hands deficit, has been attributed to a mismatch between the somatotopic and body-centred frames of reference, onto which somatosensory stimuli are automatically mapped. Whether or not such crossed-hands deficit occurs also when delivering nociceptive stimuli has not been previously investigated. In this study, participants performed a temporal order judgement (TOJ) task in which pairs of either nociceptive or tactile stimuli were delivered, one to each hand, while their arms were either crossed over the body midline or uncrossed. We observed that crossing the hands over the midline significantly decreases the ability to determine the stimulus order when a pair of nociceptive stimuli is delivered to the hands, and that this crossed-hands deficit has a temporal profile similar to that observed for tactile stimuli. These findings suggest that similar mechanisms for integrating somatotopic and body-centred frames of reference underlie the ability to localise both nociceptive and tactile stimuli in space., (Copyright © 2012 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.)

Objectives: Reconceptualization of pain and reduction of pain-related catastrophizing are primary objectives in chronic pain rehabilitation. Teaching people about the underlying biology of pain has been shown to facilitate these objectives. The objective of this study was to investigate whether written metaphor and story can be used to increase knowledge of the biology of pain and reduce pain-related catastrophizing., Methods: In this randomized single-blind partial cross-over controlled trial, 79 people with chronic pain received either a booklet of metaphors and stories conveying key pain biology concepts or a booklet containing advice on how to manage chronic pain according to established cognitive-behavioral principles. The primary outcome variables, pain biology knowledge and catastrophizing, were measured before randomization, at 3 weeks and at 3 months, at which time the control group was crossed over to receive the metaphors and stories booklet. Pain and disability were secondary outcome variables., Results: The Metaphors group showed larger changes in both variables (time × group interactions: P < 0.01, effect size Cohen d = 0.7 for catastrophizing and 1.7 for pain biology knowledge). Gains were maintained for at least 3 months. Changes were replicated in the Advice group when crossed over. There was no change in pain or self-reported disability in either group., Discussion: We conclude that providing educational material through metaphor and story can assist patients to reconceptualize pain and reduce catastrophizing. Metaphor and story could be used as a precurser to other interventions that target functional capacity.

Cytokine concentrations are thought to be affected by methods of sampling and processing and by storage conditions. In this study we compared 17 cytokine concentrations obtained from plasma and serum at baseline and after a controlled thaw condition. We found that absolute agreement was poor between concentrations of cytokines in plasma and serum, except for MIP1 β . A thaw condition significantly changed the concentrations of most cytokines, but serum appeared less affected by this than plasma was. Closer examination using Bland-Altman analyses revealed that for each comparison, agreement was moderately good for many cytokine concentrations. This is important because measures of agreement must be interpreted based on the required precision, which may differ between clinical and research demands. We also identified that for some cytokines, the relationship between serum and plasma is affected by concentration, thus advocating for the use of appropriate methods when performing such comparisons in studies such as systematic reviews and meta-analyses.

Objectives: To test the proof of principle that active anodal transcranial direct current stimulation (tDCS) applied to the motor cortex reduces pain significantly more than sham stimulation in a group of participants with chronic nonspecific low back pain., Methods: The study utilized a within-participants sham-controlled, interrupted time series design. A sample of 8 participants was recruited. After 3 days of baseline measures, patients entered a 15-day experimental period (Mondays to Fridays) for 3 consecutive weeks. During this period each patient received sham stimulation daily until a randomly allocated day when active stimulation was commenced. Active stimulation was then given daily for the remaining days of the experimental period. Both the participants and the assessors were blinded. The primary outcomes were average pain intensity and unpleasantness in the last 24 hours measured using a visual analogue scale. Secondary outcomes included self-reported disability, depression and anxiety, a battery of cognitive tests to monitor for unwanted effects of stimulation, and patients' perceptions of whether they had received active or sham stimulation. Data were analyzed using generalized estimating equations., Results: No significant effect was seen in the primary outcomes between active and sham stimulation (average pain intensity P = 0.821, unpleasantness P = 0.937) or across any other clinical variables. There was evidence that patients may have been able to distinguish between the active and sham conditions (P = 0.035)., Discussion: These results do not provide evidence that tDCS is effective in the treatment of chronic back pain. The use of a small convenience sample limits the generalizability of these findings and precludes definitive conclusions on the efficacy of tDCS in chronic nonspecific low back pain.

Unlabelled: Graded motor imagery (GMI) is becoming increasingly used in the treatment of chronic pain conditions. The objective of this systematic review was to synthesize all evidence concerning the effects of GMI and its constituent components on chronic pain. Systematic searches were conducted in 10 electronic databases. All randomized controlled trials (RCTs) of GMI, left/right judgment training, motor imagery, and mirror therapy used as a treatment for chronic pain were included. Methodological quality was assessed using the Cochrane risk of bias tool. Six RCTs met our inclusion criteria, and the methodological quality was generally low. No effect was seen for left/right judgment training, and conflicting results were found for motor imagery used as stand-alone techniques, but positive effects were observed for both mirror therapy and GMI. A meta-analysis of GMI versus usual physiotherapy care favored GMI in reducing pain (2 studies, n = 63; effect size, 1.06 [95% confidence interval, .41, 1.71]; heterogeneity, I(2) = 15%). Our results suggest that GMI and mirror therapy alone may be effective, although this conclusion is based on limited evidence. Further rigorous studies are needed to investigate the effects of GMI and its components on a wider chronic pain population., Perspective: This systematic review synthesizes the evidence for GMI and its constituent components on chronic pain. This review may assist clinicians in making evidence-based decisions on managing patients with chronic pain conditions., (Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.)

Objectives: We conducted a systematic review of the literature with meta-analysis to determine whether complex regional pain syndrome (CRPS) is associated with a specific inflammatory profile and whether this is dependent on the duration of the condition., Methods: Comprehensive searches of the literature using MEDLINE, Embase, Scopus, Web of Science, and reference lists from published reviews identified articles that measured inflammatory factors in CRPS. Two independent investigators screened titles and abstracts, and performed data extraction and risk of bias assessments. Studies were subgrouped by medium (blood, blister fluid, and CSF) and duration (acute and chronic CRPS). Where possible, meta-analyses of inflammatory factor concentrations were performed and pooled effect sizes were calculated using random-effects models., Results: Twenty-two studies were included in the systematic review and 15 in the meta-analysis. In acute CRPS, the concentrations of interleukin (IL)-8 and soluble tumor necrosis factor receptors I (sTNF-RI) and II (sTNF-RII) were significantly increased in blood. In chronic CRPS, significant increases were found in 1) TNFα, bradykinin, sIL-1RI, IL-1Ra, IL-2, sIL-2Ra, IL-4, IL-7, interferon-γ, monocyte chemoattractant protein-1 (MCP-1), and sRAGE (soluble receptor for advanced glycation end products) in blood; 2) IL-1Ra, MCP-1, MIP-1β, and IL-6 in blister fluid; and 3) IL-1β and IL-6 in CSF. Chronic CRPS was also associated with significantly decreased 1) substance P, sE-selectin, sL-selectin, sP-selectin, and sGP130 in blood; and 2) soluble intercellular adhesion molecule-1 (sICAM-1) in CSF. Most studies failed to meet 3 or more of our quality criteria., Conclusion: CRPS is associated with the presence of a proinflammatory state in the blood, blister fluid, and CSF. Different inflammatory profiles were found for acute and chronic cases.

Numerous clinical conditions, including complex regional pain syndrome, are characterized by autonomic dysfunctions (e.g. altered thermoregulation, sometimes confined to a single limb), and disrupted cortical representation of the body and the surrounding space. The presence, in patients with complex regional pain syndrome, of a disruption in spatial perception, bodily ownership and thermoregulation led us to hypothesize that impaired spatial perception might result in a spatial-dependent modulation of thermoregulation and bodily ownership over the affected limb. In five experiments involving a total of 23 patients with complex regional pain syndrome of one arm and 10 healthy control subjects, we measured skin temperature of the hand with infrared thermal imaging, before and after experimental periods of either 9 or 10 min each, during which the hand was held on one or the other side of the body midline. Tactile processing was assessed by temporal order judgements of pairs of vibrotactile stimuli, delivered one to each hand. Pain and sense of ownership over the hand were assessed by self-report scales. Across experiments, when kept on its usual side of the body midline, the affected hand was 0.5 ± 0.3°C cooler than the healthy hand (P < 0.02 for all, a common finding in cold-type complex regional pain syndrome), and tactile stimuli delivered to the healthy hand were prioritized over those delivered to the affected hand. Simply crossing both hands over the midline resulted in (i) warming of the affected hand (the affected hand became 0.4 ± 0.3°C warmer than when it was in the uncrossed position; P = 0.01); (ii) cooling of the healthy hand (by 0.3 ± 0.3°C; P = 0.02); and (iii) reversal of the prioritization of tactile processing. When only the affected hand was crossed over the midline, it became warmer (by 0.5 ± 0.3°C; P = 0.01). When only the healthy hand was crossed over the midline, it became cooler (by 0.3 ± 0.3°C; P = 0.01). The temperature change of either hand was positively related to its distance from the body midline (pooled data: r = 0.76, P < 0.001). Crossing the affected hand over the body midline had small but significant effects on both spontaneous pain (which was reduced) and the sense of ownership over the hand (which was increased) (P < 0.04 for both). We conclude that impaired spatial perception modulated temperature of the limbs, tactile processing, spontaneous pain and the sense of ownership over the hands. These results show that complex regional pain syndrome involves more complex neurological dysfunction than has previously been considered.

Objective: Playing a sport or a musical instrument is presumed to improve motor ability. One would therefore predict that children who play a sport or music are better at motor imagery tasks, which rely on an intact cortical proprioceptive representation and precise motor planning, than children who do not. The authors tested this prediction., Methods: This study involved an online questionnaire and then a motor imagery task. The task measured the reaction time (RT) and the accuracy for left/right-hand judgements in children aged 5 to 17 years. Forty pictured hands (20 left), held in various positions and rotated zero, 90°, 180° or 270°, were displayed on a screen. Participants indicated whether the displayed hands were left or right by pressing keys on a keyboard., Results: Fifty-seven children (30 boys; mean±SD age=10±3.3 years) participated. The mean±SD RT was 3015.4±1330.0 ms and the accuracy was 73.9±16.6%. There was no difference in RT between children who played sport, music, neither or both (four-level one-way analysis of variance, p=0.85). There was no difference in accuracy between groups either (Kruskal-Wallis, p=0.46). In a secondary analysis, participants whose parents rated them as being 'clumsy' were no slower (n.s.) but were about 25% less accurate than those rated coordinated or very coordinated (p<0.05)., Conclusion: The authors conclude against the intuitively sensible and widely held view that participation in a sport or music is associated with better cortical proprioceptive representation and motor planning. Secondary analyses suggest that parent-rated clumsiness is negatively related to motor imagery performance.

Objectives: The aim of this study was to determine whether visualization of the back influenced parameters of movement-related pain in people with chronic nonspecific low back pain., Methods: We used a randomized cross-over experiment in which 25 participants performed repeated lumbar spine movements under 2 conditions. In the visual feedback condition, patients were able to visualize their back as it moved by the use of mirrors. In the control condition, the mirror was covered so no visualization of the back was possible., Results: The average postmovement pain intensity after participants had moved with visual feedback was less (35.5 ± 22.8 mm) than when they moved without visual feedback (44.7 ± 26.0 mm). This difference was statistically significant (mean difference=9.3, 95% confidence interval: 2.8-15.7 F(1,22)=8.82, P=0.007). The average time to ease after participants had moved with visual feedback was shorter (44.5 s ± 53.8) than when they moved without visual feedback (94.4 s ± 80.7). This difference was also statistically significantly (mean difference=49.9, 95% confidence interval: 19.3-80.6, F(1,22)=8.82, P=0.003)., Discussion: Patients with chronic nonspecific low back pain reported less increase in pain and faster resolution of pain when moving in an environment that enabled them to visualize their back. This is consistent with emerging research on the use of mirror visual feedback in other long-standing pain problems and suggests that similar lines of inquiry may be worth pursuing in the chronic nonspecific low back pain population.

Objectives: Tactile dysfunction in chronic pain is explained as disruption in somatotopically based processing of stimuli. We hypothesized that people with chronic back pain also demonstrate a spatially defined disruption of tactile processing., Methods: In 3 cross-sectional experiments, 26 patients with unilateral low back pain and 12 healthy controls made temporal order judgments of pairs of tactile stimuli. We analyzed the stimulus onset asynchrony at which participants perceived them to be simultaneous (PSS). Stimuli were delivered to either side of the back or to both index fingers. For hand stimuli, the position of the hands were 1) one either side of the back or 2) in front of the body, 3) one behind the back and one in front on the affected side or 4) on the unaffected side., Results: In patients, mean ± SD PSS for stimuli to either side of the lower back occurred when the affected side received the stimulus 25 ± 25 msec before the unaffected side. PSS for stimuli to the hands with one hand held near the affected area was similar when the other hand was behind the back on the opposite side of the midline (17 ± 17 msec) or in front of the body on the affected side (31 ± 21 msec). These PSS values were greater than that for all other conditions and in healthy controls (p < 0.01), which approached zero., Conclusions: Spatial representation of vibrotactile stimuli is disrupted in chronic unilateral back pain.

Recent neuroscientific evidence has confirmed the important role of cognitive and behavioral factors in the development and treatment of chronic pain. Neuropathic and musculoskeletal pain are associated with substantial reorganization of the primary somatosensory and motor cortices as well as regions such as the anterior cingulate cortex and insula. What is more, in patients with chronic low back pain and fibromyalgia, the amount of reorganizational change increases with chronicity; in phantom limb pain and other neuropathic pain syndromes, cortical reorganization correlates with the magnitude of pain. These findings have implications for both our understanding of chronic pain and its prevention and treatment. For example, central alterations may be viewed as pain memories that modulate the processing of both noxious and nonnoxious input to the somatosensory system and outputs of the motor and other response systems. The cortical plasticity that is clearly important in chronic pain states also offers potential targets for rehabilitation. The authors review the cortical changes that are associated with chronic pain and the therapeutic approaches that have been shown to normalize representational changes and decrease pain and discuss future directions to train the brain to reduce chronic pain.

A systematic review identified tactile assessments used in children with cerebral palsy (CP), but their reproducibility is unknown. Sixteen children with unilateral CP and 31 typically developing children (TDC) were assessed 2-4 weeks apart. Test-retest percent agreements within one point for children with unilateral CP (and TDC) were Semmes-Weinstein monofilaments: 75% (90%); single-point localization: 69% (97%); static two-point discrimination: 93% (97%); and moving two-point discrimination: 87% (97%). Test-retest reliability for registration and unilateral spatial tactile perception tests was high in children with CP (intraclass correlation coefficient [ICC] = 0.79-0.96). Two tests demonstrated a learning effect for children with CP, double simultaneous and tactile texture perception. Stereognosis had a ceiling effect for TDC (ICC = 0) and variability for children with CP (% exact agreement = 47%-50%). The Semmes-Weinstein monofilaments, single-point localization, and both static and moving two-point discrimination are recommended for use in practice and research. Although recommended to provide a comprehensive assessment, the measures of double simultaneous, stereognosis, and tactile texture perception may not be responsive to change over time in children with unilateral CP.

Background: There is good evidence from studies conducted in a single-centre research setting for the efficacy of graded motor imagery (GMI) treatment, a complex physiotherapy intervention, to reduce pain in long-standing complex regional pain syndrome (CRPS). However, whether GMI is effective in clinical practice is not established., Aim: To establish whether GMI is effective in clinical practice., Methods: We undertook a prospective audit of GMI treatment at two UK centres with a special interest in the management of patients with CRPS. All patients received GMI, in conjunction with a range of other 'best practice' physical and psychological interventions., Results: The patients' average pain intensities did not improve with treatment [centre 1: n = 20, pre-post numeric rating scale (NRS) difference 0.6 [confidence interval (CI) -0.3 to 1.5]; centre 2: n = 12, pre-post NRS difference 0.2 (CI: -0.9 to 1.2)]. Patients at centre 1 reported significant functional improvement. Improved performance on left/right judgement replicated in both centres seen in the clinical trials., Conclusions: The failure of our real-world implementation of GMI suggests that better understanding of both the GMI methodology and its interaction with other treatment methods is required to ensure that GMI research results can be translated into clinical practice. Our results highlight challenges with the translation of complex interventions for chronic pain conditions into clinical practice., (© 2011 European Federation of International Association for the Study of Pain Chapters.)

Objective: To determine the relationship between tactile function and upper-limb function in children with unilateral cerebral palsy (CP)., Design: Cross-sectional study., Setting: Assessments were performed in community or hospital venues or in participants' homes., Participants: Recruitment information was sent to 253 possible participants with unilateral CP (aged 8-18 y), and N=52 participated (median age [interquartile range], 12 y [9-14 y]; Gross Motor Functional Classification System level I=34; II=18; Manual Abilities Classification Scale level I=36; II=16)., Interventions: Not applicable., Main Outcome Measures: Tactile assessment included 1 test of registration, 5 tests for spatial perception, and 1 test for texture perception. Upper-limb motor function was assessed using 2 unimanual tests, the Melbourne Unilateral Upper Limb Assessment (MUUL) and Jebsen-Taylor Test of Hand Function (JTTHF), and 1 bimanual test, the Assisting Hand Assessment (AHA)., Results: Tactile registration and all tests of spatial perception were moderately related to the MUUL, JTTHF, and AHA (P<.001). Texture perception was not related to upper-limb motor function. Regression analysis showed that single point localization, a unilateral tactile spatial perception test, contributed most strongly to unimanual capacity (29% explained variance in MUUL and 26% explained variance in JTTHF), whereas double simultaneous, a bilateral tactile spatial perception test, contributed most strongly to bimanual performance (33% for the AHA)., Conclusions: Spatial tactile deficits account for approximately 30% of the variance in upper-limb motor function in children with unilateral CP. This emphasizes the need for routine tactile assessment and targeted treatment of tactile spatial deficits in this population., (Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: Chronic pain is a common problem that is associated with mood disorders such as depression. The Depression, Anxiety, and Stress Scales (DASS-21) questionnaire is commonly used to help measure disordered mood. In this study, we used Rasch analysis to analyze the clinimetric properties of the DASS-21 in a chronic low back pain sample., Study Design and Setting: A Rasch analysis was conducted on data collected as a part of a randomized hospital-based placebo-controlled trial. DASS-21 questionnaires were completed by the 154 enrolled participants., Results: The DASS-21 subscales fit the Rasch model. No differential item functioning was detected for age, gender, pain severity, or disability. Reliability for individual use was supported for the depression subscale (Person Separation Index [PSI]=0.86) but group use only for the anxiety (PSI=0.74) and stress (PSI=0.82) subscales. A DASS-21 aggregate score of "negative affect" lacked fit to the Rasch model (χ(2)=191.48, P<0.001)., Conclusion: This is the first study that used Rasch analysis to demonstrate that the DASS-21 subscales demonstrate adequate measurement properties for research involving groups with chronic pain. Only the DASS-21 depression subscale demonstrated adequate reliability for use with individuals with chronic pain. The use of a single DASS-21 aggregate score as a measure of "negative affect" was not supported., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Illusions that induce a feeling of ownership over an artificial body or body-part have been used to explore the complex relationships that exist between the brain's representation of the body and the integrity of the body itself. Here we discuss recent findings in both healthy volunteers and clinical populations that highlight the robust relationship that exists between a person's sense of ownership over a body part, cortical processing of tactile input from that body part, and its physiological regulation. We propose that a network of multisensory and homeostatic brain areas may be responsible for maintaining a 'body-matrix'. That is, a dynamic neural representation that not only extends beyond the body surface to integrate both somatotopic and peripersonal sensory data, but also integrates body-centred spatial sensory data. The existence of such a 'body-matrix' allows our brain to adapt to even profound anatomical and configurational changes to our body. It also plays an important role in maintaining homeostatic control over the body. Its alteration can be seen to have both deleterious and beneficial effects in various clinical populations., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The sense of body ownership can be easily disrupted during illusions and the most common illusion is the rubber hand illusion. An idea that is rapidly gaining popularity in clinical pain medicine is that body ownership illusions can be used to modify pathological pain sensations and induce analgesia. However, this idea has not been empirically evaluated. Two separate research laboratories undertook independent randomized repeated measures experiments, both designed to detect an effect of the rubber hand illusion on experimentally induced hand pain. In Experiment 1, 16 healthy volunteers rated the pain evoked by noxious heat stimuli (5 s duration; interstimulus interval 25 s) of set temperatures (47°, 48° and 49°C) during the rubber hand illusion or during a control condition. There was a main effect of stimulus temperature on pain ratings, but no main effect of condition (p = 0.32), nor a condition x temperature interaction (p = 0.31). In Experiment 2, 20 healthy volunteers underwent quantitative sensory testing to determine heat and cold pain thresholds during the rubber hand illusion or during a control condition. Secondary analyses involved heat and cold detection thresholds and paradoxical heat sensations. Again, there was no main effect of condition on heat pain threshold (p = 0.17), nor on cold pain threshold (p = 0.65), nor on any of the secondary measures (p<0.56 for all). We conclude that the rubber hand illusion does not induce analgesia.

Purpose: Tactile deficits have been understudied in children with unilateral cerebral palsy (UCP) using a limited range of tactile assessments. This study aims to characterize performance across a comprehensive battery of tactile registration and perception assessments in children with UCP and typically developing children (TDC)., Methods: Fifty-two children with UCP (Gross Motor Function Classification System I = 34, II = 18; Manual Ability Classification System I = 36, II = 16) and 34 TDC were assessed using Semmes Weinstein Monofilaments (tactile registration), and single-point localization, double simultaneous, static and moving two-point discrimination, stereognosis, and texture perception (tactile perception)., Results: Children with UCP performed consistently worse with their impaired hand than their unimpaired hand (Z = 2.77-5.61; p < 0.005). Both hands of children with UCP performed worse than either hand of TDC (Z = -2.08 to 5.23; p = 0.037-< 0.001). Forty percent of children with UCP had tactile registration and perception deficits, 37% had perception deficits only and 23% had no tactile deficit. The larger the tactile registration deficit, the poorer the performance on all tactile perceptual tests (r = 0.568-0.670; p < 0.001)., Conclusions: Most children with UCP demonstrate poor tactile perception and over one-third also demonstrate poor tactile registration. We contend that tactile dysfunction may contribute to functional impairment and is a possible target for intervention. [, Implications for Rehabilitation: • Cerebral palsy (CP) is the most prevalent physical disability in childhood, with an incidence of approximately 2 cases per 1000 live births; about 35% of children with CP have unilateral cerebral palsy (UCP).• Assessment and treatment has been focused on the motor impairment; however, it is known that children with UCP are also likely to have sensory impairment.• Understanding the nature and severity of sensory, specifically tactile, impairment in children with UCP will assist therapists to direct treatment accordingly and possibly impact the motor impairment.]

Background: Many double-blind clinical trials of transcranial direct current stimulation (tDCS) use stimulus intensities of 2 mA despite the fact that blinding has not been formally validated under these conditions. The aim of this study was to test the assumption that sham 2 mA tDCS achieves effective blinding., Methods: A randomised double blind crossover trial. 100 tDCS-naïve healthy volunteers were incorrectly advised that they there were taking part in a trial of tDCS on word memory. Participants attended for two separate sessions. In each session, they completed a word memory task, then received active or sham tDCS (order randomised) at 2 mA stimulation intensity for 20 minutes and then repeated the word memory task. They then judged whether they believed they had received active stimulation and rated their confidence in that judgement. The blinded assessor noted when red marks were observed at the electrode sites post-stimulation., Results: tDCS at 2 mA was not effectively blinded. That is, participants correctly judged the stimulation condition greater than would be expected to by chance at both the first session (kappa level of agreement (κ) 0.28, 95% confidence interval (CI) 0.09 to 0.47 p=0.005) and the second session (κ=0.77, 95%CI 0.64 to 0.90), p=<0.001) indicating inadequate participant blinding. Redness at the reference electrode site was noticeable following active stimulation more than sham stimulation (session one, κ=0.512, 95%CI 0.363 to 0.66, p<0.001; session two, κ=0.677, 95%CI 0.534 to 0.82) indicating inadequate assessor blinding., Conclusions: Our results suggest that blinding in studies using tDCS at intensities of 2 mA is inadequate. Positive results from such studies should be interpreted with caution.

This review evaluates the clinimetric properties of tactile assessments for children with cerebral palsy. Assessment of registration was reported using Semmes Weinstein Monofilaments (SWMs) or exteroception. Assessment of two-point discrimination was reported using the Disk-Criminator® or paperclip methods; Single point localization and double simultaneous were reported from the Neurosensory Motor Developmental Assessment (NSMDA); graphaesthesia was reported from the Sensory Integration and Praxis Test (SIPT); and stereognosis was assessed using Manual Form Perception from the SIPT and the Klingels method (Klingels, K. et al. (2010). Upper limb motor and sensory impairments in children with hemiplegic cerebral palsy. Can they be measured reliably? Disability and Rehabilitation, 32(5), 409-416) and the Cooper method (Cooper, J., Majnemer, A., Rosenblatt, B., & Birnbaum, R. (1995). The determination of sensory deficits in children with hemiplegic cerebral palsy. Journal of Child Neurology, 10, 300-309). The SIPT and NSMDA demonstrated stronger content validity. Inter-rater reliability was excellent for SIPT (ICC = 0.99) and exteroception (k = 0.88). Test-retest reliability was excellent for exteroception (k = 0.89) and stereognosis (ICC = 0.86; 100%), moderate for SIPT (r = 0.69-0.74) and poor for SWM (k = 0.22). Together these assessments measure tactile registration and spatial perception. Temporal and textural tests are to be developed for comprehensive tactile examination.

Purpose of Review: Phantom pain is a frequent consequence of amputation or deafferentation. There are many possible contributing mechanisms, including stump-related pathology, spinal and cortical changes. Phantom limb pain is notoriously difficult to treat. Continued consideration of the factors associated with phantom pain and its treatment is of utmost importance, not only to advance the scientific knowledge about the experience of the body and neuropathic pain, but also fundamentally to promote efficacious pain management., Recent Findings: This review first discusses the mechanisms associated with phantom pain and summarizes the current treatments. The mechanisms underlying phantom pain primarily relate to peripheral/spinal dysfunction, and supraspinal and central plasticity in sensorimotor body representations. The most promising methods for managing phantom pain address the maladaptive changes at multiple levels of the neuraxis, for example, complementing pharmacological administration with physical, psychological or behavioural intervention. These supplementary techniques are even efficacious in isolation, perhaps by replacing the absent afferent signals from the amputated limb, thereby restoring disrupted bodily representations., Summary: Ultimately, for optimal patient outcomes, treatments should be both symptom and mechanism targeted.

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.

A recent study has found that activity in multisensory brain areas, namely the premotor cortex, intraparietal cortex and the putamen, mirrors the vividness of ownership over a mannequin, induced by the body-swap illusion., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

A complex regional pain syndrome (CRPS)--multiple system dysfunction, severe and often chronic pain, and disability--can be triggered by a minor injury, a fact that has fascinated scientists and perplexed clinicians for decades. However, substantial advances across several medical disciplines have recently improved our understanding of CRPS. Compelling evidence implicates biological pathways that underlie aberrant inflammation, vasomotor dysfunction, and maladaptive neuroplasticity in the clinical features of CRPS. Collectively, the evidence points to CRPS being a multifactorial disorder that is associated with an aberrant host response to tissue injury. Variation in susceptibility to perturbed regulation of any of the underlying biological pathways probably accounts for the clinical heterogeneity of CRPS., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The sense of body ownership, knowledge that parts of our body ‘belong’ to us, is presumably developed using sensory information. Cutaneous signals seem ideal for this and can modify the sense of ownership. For example, an illusion of ownership over an artificial rubber hand can be induced by synchronously stroking both the subject’s hidden hand and a visible artificial hand. Like cutaneous signals, proprioceptive signals (e.g. frommuscle receptors) exclusively signal events occurring in the body, but the influence of proprioceptors on the sense of body ownership is not known. We developed a technique to generate an illusion of ownership over an artificial plastic finger, using movement at the proximal interphalangeal joint as the stimulus. We then examined this illusion in 20 subjects when their index finger was intact and when the cutaneous and joint afferents from the finger had been blocked by local anaesthesia of the digital nerves. Subjects still experienced an illusion of ownership, induced by movement, over the plastic finger when the digital nerves were blocked. This shows that local cutaneous signals are not essential for the illusion and that inputs arising proximally, presumably from receptors in muscles which move the finger, can influence the sense of body ownership. Contrary to other studies, we found no evidence that voluntary movements induce stronger illusions of body ownership than those induced by passive movement. It seems that the congruence of sensory stimuli ismore important to establish body ownership than the presence of multiple sensory signals.

The ability to determine precisely the location of sensory stimuli is fundamental to how we interact with the world; indeed, to our survival. Crossing the hands over the body midline impairs this ability to localize tactile stimuli. We hypothesized that crossing the arms would modulate the intensity of pain evoked by noxious stimulation of the hand. In two separate experiments, we show (1) that the intensity of both laser-evoked painful sensations and electrically-evoked nonpainful sensations were decreased when the arms were crossed over the midline, and (2) that these effects were associated with changes in the multimodal cortical processing of somatosensory information. Critically, there was no change in the somatosensory-specific cortical processing of somatosensory information. Besides studies showing relief of phantom limb pain using mirrors, this is the first evidence that impeding the processes by which the brain localises a noxious stimulus can reduce pain, and that this effect reflects modulation of multimodal neural activities. By showing that the neural mechanisms by which pain emerges from nociception represent a possible target for analgesia, we raise the possibility of novel approaches to the treatment of painful clinical conditions. Crossing the arms over the midline impairs multimodal processing of somatosensory stimuli and induces significant analgesia to noxious hand stimulation., (Copyright © 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.)

Background: Complex regional pain syndrome (CRPS) may occur after trauma, usually to one limb, and is characterized by pain and disturbed blood flow, temperature regulation and motor control. Approximately 25% of cases develop fixed dystonia. Involvement of dysfunctional GABAergic interneurons has been suggested, however the mechanisms that underpin fixed dystonia are still unknown. We hypothesized that dystonia could be the result of aberrant proprioceptive reflex strengths of position, velocity or force feedback., Methods: We systematically characterized the pattern of dystonia in 85 CRPS-patients with dystonia according to the posture held at each joint of the affected limb. We compared the patterns with a neuromuscular computer model simulating aberrations of proprioceptive reflexes. The computer model consists of an antagonistic muscle pair with explicit contributions of the musculotendinous system and reflex pathways originating from muscle spindles and Golgi tendon organs, with time delays reflective of neural latencies. Three scenarios were simulated with the model: (i) increased reflex sensitivity (increased sensitivity of the agonistic and antagonistic reflex loops); (ii) imbalanced reflex sensitivity (increased sensitivity of the agonistic reflex loop); (iii) imbalanced reflex offset (an offset to the reflex output of the agonistic proprioceptors)., Results: For the arm, fixed postures were present in 123 arms of 77 patients. The dominant pattern involved flexion of the fingers (116/123), the wrists (41/123) and elbows (38/123). For the leg, fixed postures were present in 114 legs of 77 patients. The dominant pattern was plantar flexion of the toes (55/114 legs), plantar flexion and inversion of the ankle (73/114) and flexion of the knee (55/114).Only the computer simulations of imbalanced reflex sensitivity to muscle force from Golgi tendon organs caused patterns that closely resembled the observed patient characteristics. In parallel experiments using robot manipulators we have shown that patients with dystonia were less able to adapt their force feedback strength., Conclusions: Findings derived from a neuromuscular model suggest that aberrant force feedback regulation from Golgi tendon organs involving an inhibitory interneuron may underpin the typical fixed flexion postures in CRPS patients with dystonia.

Background: Voluntary lumbopelvic control is compromised in patients with back pain. Loss of proprioceptive acuity is one contributor to decreased control. Several reasons for decreased proprioceptive acuity have been proposed, but the integrity of cortical body maps has been overlooked. We investigated whether tactile acuity, a clear clinical signature of primary sensory cortex organisation, relates to lumbopelvic control in people with back pain., Methods: Forty-five patients with back pain and 45 age- and sex-matched healthy controls participated in this cross-sectional study. Tactile acuity at the back was assessed using two-point discrimination (TPD) threshold in vertical and horizontal directions. Voluntary motor control was assessed using an established battery of clinical tests., Results: Patients performed worse on the voluntary lumbopelvic tasks than healthy controls did (p<0.001). TPD threshold was larger in patients (mean (SD)=61 (13) mm) than in healthy controls (44 (10) mm). Moreover, larger TPD threshold was positively related to worse performance on the voluntary lumbopelvic tasks (Pearson's r=0.49; p<0.001)., Discussion: Tactile acuity, a clear clinical signature of primary sensory cortex organisation, relates to voluntary lumbopelvic control. This relationship raises the possibility that the former contributes to the latter, in which case training tactile acuity may aid recovery and assist in achieving normal motor performance after back injury.

Background: To test whether working body schema of the trunk is disrupted in people with back pain using a motor imagery task in which one decides whether a pictured model has their trunk rotated to the left or to the right. The authors hypothesised that chronic back pain is associated with reduced accuracy of left/right trunk rotation judgements., Methods: 21 Patients with back pain and 14 controls completed two tasks, each involving two trials of 40 images: a left/right hand judgement task, which was used as a control task, and the left/right trunk rotation judgement task. Two (task) × three (group: bilateral back pain, unilateral back pain and control) analyses of variance were undertaken on mean response time and accuracy., Results: Response time was similar across participants and tasks (NS). Accuracy was not. The patients with bilateral back pain made more mistakes on the left/right trunk rotation task than patients with unilateral back pain, who in turn made more mistakes on that task than the controls (body part × group interaction; p<0.001). The mean (95% CI) accuracy for left/right trunk rotation judgements was 53.4% (44.5% to 62.3%) for the patients with bilateral back pain, 67.2% (60.2% to 74.1%) for the patients with unilateral back pain and 87% (75% to 98%) for the control participants. This pattern was not observed on the left/right-hand judgement task, on which all three groups made correct judgements about 83% of the time (NS)., Discussion: Chronic back pain is associated with disruption of the working body schema of the trunk. This might be an important contributor to motor control abnormalities seen in this population.

There is increasing evidence that chronic pain problems are characterised by alterations in brain structure and function. Chronic back pain is no exception. There is a growing sentiment, with accompanying theory, that these brain changes contribute to chronic back pain, although empirical support is lacking. This paper reviews the structural and functional changes of the brain that have been observed in people with chronic back pain. We cast light on the clinical implications of these changes and the possibilities for new treatments but we also advise caution against concluding their efficacy in the absence of solid evidence to this effect., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Purpose:  Visual perception difficulties are common in children with cerebral palsy - hemiplegia, however it is not known which assessment tool is the best for this population. This systematic review evaluates the clinimetric properties of visual perception assessments for children with hemiplegia., Method: Databases were searched for assessments that: (i) measured visual perception; (ii) were reported in studies with children with hemiplegia and (iii) had clinimetric data available to assessors., Results:  Three assessments met criteria: the Test of Visual Perceptual Skills (TVPS), Motor-Free Visual Perceptual Test (MVPT) and Developmental Test of Visual Perception (DTVP). Factor analysis has been completed for the TVPS and DTVP, with both assessments and especially the TVPS, demonstrating some subtests that do not load significantly for the first factor of motor-free visual perception. All three assessments demonstrate variable construct and criterion validity with other clinical assessments. The DTVP, MVPT and TVPS demonstrate high test-retest reliability for total scores, but individual TVPS subtests are less reliable., Conclusions:  The MVPT and DTVP show the best clinimetric data, however, less research has been completed on these tests than the TVPS. Further research is required to confirm the validity and reliability of the MVPT and DTVP for children with hemiplegia.

Study Design: Cross-sectional design., Objective: To compare lumbar multifidus electromyographic activity (EMG) during predictable and unpredictable trunk loading between people with and without recurrent unilateral low back pain (LBP) during symptom remission., Summary of Background Data: Unpredictable loading is a common injury mechanism for LBP. Paraspinal muscle responses to trunk loading differ between people with and without a history of LBP, but whether the response differs between specific regions within the paraspinal muscles is unclear. Differences between deep (DM) and superficial fibers (SM) of multifidus have been implicated in other tasks. It is unknown whether DM and SM EMG differ between people in remission from recurrent LBP and healthy people during trunk loading., Methods: DM and SM EMG was recorded bilaterally at L5 with intramuscular electrodes during predictable and unpredictable trunk loading and compared during 10 milliseconds epochs (250 milliseconds before to 150 milliseconds after loading) between sides, loading conditions, and groups., Results: DM EMG increased above baseline before and after predictable load onset, but returned to baseline at the time of impact. Both DM EMG bursts were less in the remission group and less on the non-painful side. Peak SM EMG amplitude on the previously painful side was earlier in the remission group than healthy participants. DM and SM EMG were less after unpredictable load onset in the remission group than healthy participants., Conclusion: Despite symptom remission, DM EMG during predictable loading and DM and SM EMG during unpredictable loading were less in people with recurrent LBP than healthy participants.

The feeling we have of our own body, sometimes called "body image," is fundamental to self-awareness. However, by altering sensory input, the body image can be modified into impossible configurations. Can impossible movements of the body image be conjured solely via internally generated mechanisms, and, if so, do the structural characteristics of the body image modify to accommodate the new movements? We encouraged seven amputees with a vivid phantom arm to learn to perform a phantom wrist movement that defied normal anatomical constraints. Four reported success. Learning the impossible movement coincided in time with a profound change in the body image of the arm, including a sense of ownership and agency over a modified wrist joint. Remarkably, some previous movements and functional tasks involving the phantom arm became more difficult once the shift in body image had occurred. Crucially, these introspective reports were corroborated by robust empirical data from motor imagery tasks, about which amputees were naïve and to which assessors were blind. These results provide evidence that: a completely novel body image can be constructed solely by internally generated mechanisms; that the interdependence between movement repertoire and structural constraints of the body persists even when the structural constraints imparted by the body do not--the body image we construct still constrains imagined movements; and that motor learning does not necessarily need sensory feedback from the body or external feedback about task performance.

Complex regional pain syndrome (CRPS) occurs after stroke, but most cases develop after peripheral trauma and without evidence of brain trauma. However, CRPS is associated with symptoms that appear similar to those observed in patients suffering from hemispatial neglect. Ten participants (four males) with CRPS of one arm performed temporal order judgements of pairs of vibrotactile stimuli, one delivered to each hand, at one of 10 possible stimulus onset asynchronies, under two conditions: arms held each side of the midline and arms crossed over the midline. Participants released a foot switch to indicate which hand had been stimulated first. The order of conditions was randomized and the foot under which the switch was positioned was counterbalanced. There were two blocks of 150 trials in each condition. The stimulus onset asynchronicity at which the participants were equally likely to select either hand, the point of subjective simultaneity (PSS), was compared between conditions and between those with left or right-sided symptoms. When arms were not crossed, the participants prioritized stimuli from the unaffected limb over those from the affected limb (mean +/- SD PSS = 25 +/- 7.5 ms) and the magnitude of the PSS strongly related to the degree to which the affected hand was cooler than the unaffected hand (r = 0.942, P < 0.001). When the arms were crossed, the effect was reversed: the participants prioritized stimuli from the affected limb over those from the unaffected limb [PSS = -18 +/- 13 ms; main effect of condition F (1, 9) = 98.6, P < 0.001]. There was no effect of the side of symptoms. These results show that CRPS is associated with a deficit in tactile processing that is defined by the space in which the affected limb normally resides, not by the affected limb itself, and which relates to the relative cooling of the affected limb. This pattern is consistent with data from those with hemispatial neglect after stroke and raises the possibility that chronic CRPS involves a type of spatial neglect.

There is a lack of quantitative evidence for spinal postures that are advocated as 'ideal' in clinical ergonomics for sitting. This study quantified surface spinal curves and examined whether subjects could imitate clinically 'ideal' directions of spinal curve at thoraco-lumbar and lumbar regions: (i) flat - at both regions (ii) long lordosis - lordotic at both regions (iii) short lordosis - thoracic kyphosis and lumbar lordosis. Ten healthy male subjects had 3-D motion sensors adhered to the skin so that sagittal spinal curves were represented by angles at thoracic (lines between T1-T5 and T5-T10), thoraco-lumbar (T5-T10 and T10-L3) and lumbar regions (T10-L3 and L3-S2). Subjects attempted to imitate pictures of spinal curves for the flat, long lordosis, short lordosis and a slumped posture, and were then given feedback/manual facilitation to achieve the postures. Repeated measures analysis of variance was used to compare spinal angles between posture and facilitation conditions. Results show that although subjects imitated postures with the same curve direction at thoraco-lumbar and lumbar regions (slumped, flat or long lordosis), they required feedback/manual facilitation to differentiate the regional curves for the short lordosis posture. Further study is needed to determine whether the clinically proposed 'ideal' postures provide clinical advantages.

Study Design: Exploratory study of regional muscle activity in different postures., Objective: To detail the relationship between spinal curves and regional muscle activity., Summary of Background Data: Sagittal balanced spinal posture (C7 above S1 in the sagittal plane) is a goal for spinal surgery and conservative ergonomics. Three combinations of thoracolumbar and lumbar spinal curves can be considered sagittal balanced postures: (i) flat-at both regions, (ii) long lordosis-lordotic at both regions, and (iii) short lordosis-thoracic kyphosis and lumbar lordosis. This study compares regional muscle activity between these 3 sagittal balanced postures in sitting, as well as a slump posture., Methods: Fine-wire electromyography (EMG) electrodes were inserted into the lumbar multifidus (deep and superficial), iliocostalis (lateral and medial), longissimus thoracis, and transversus abdominis in 14 healthy male volunteers. Fine-wire or surface EMG electrodes were also used to record activity of the obliquus internus, obliquus externus, and rectus abdominis muscles. Root mean square EMG amplitude in the flat, long lordosis, short lordosis, and slump sitting postures were normalized to maximal voluntary contraction, and also to the peak activity across the sitting postures. Muscle activity was compared between postures with a linear mixed model analysis., Results: Of the extensor muscles, it was most notable that activity of the deep and superficial fibers of lumbar multifidus increased incrementally in the 3 sagittal balanced postures; flat, long lordosis, and short lordosis (P < 0.05). Of the abdominal muscles, obliquus internus was more active in short lordosis than the other postures (P < 0.05). Comparing the sagittal balanced postures, the flat posture showed the least muscle activity (similar to the slump posture at most muscles examined)., Conclusion: Discrete combinations of muscle activity supported the 3 different sagittal balanced postures in sitting, providing new detail for surgeons, researchers, and therapists to distinguish between different sagittal balanced postures.

Threatening stimuli are thought to bias spatial attention toward the location from which the threat is presented. Although this effect is well-established in the visual domain, little is known regarding whether tactile attention is similarly affected by threatening pictures. We hypothesised that tactile attention might be more affected by cues implying physical threat to a person's bodily tissues than by cues implying general threat. In the present study, participants made temporal order judgments (TOJs) concerning which of a pair of tactile (or auditory) stimuli, one presented to either hand, at a range of inter-stimulus intervals, had been presented first. A picture (showing physical threat, general threat, or no threat) was presented in front of one or the other hand shortly before the tactile stimuli. The results revealed that tactile attention was biased toward the side on which the picture was presented, and that this effect was significantly larger for physical threat pictures than for general threat or neutral pictures. By contrast, the bias in auditory attention toward the side of the picture was significantly larger for general threat pictures than for physical threat pictures or neutral pictures. These findings therefore demonstrate a modality-specific effect of physically threatening cues on the processing of tactile stimuli, and of generally threatening cues on auditory information processing. These results demonstrate that the processing of tactile information from the body part closest to the threatening stimulus is prioritized over tactile information from elsewhere on the body.