Clinical assessments can discriminate altered body perception in patients with unilateral chronic low back pain, but not differences between affected and unaffected side

Translation, cross-cultural adaptation, and analysis of the measurement properties of the Fremantle Knee Awareness Questionnaire (FreKAQ) into Brazilian Portuguese for individuals with knee osteoarthritis

OBJECTIVE

This study aimed to translate and cross-culturally adapt the Fremantle Knee Awareness Questionnaire (FreKAQ) into Brazilian Portuguese and evaluate the measurement properties, including internal consistency, construct validity, reliability, and ceiling and floor effects in individuals with knee osteoarthritis (KOA).

METHODS

Translation, cross-cultural adaptation, and analysis of measurement properties were performed according to international recommendations. One hundred thirty-four individuals diagnosed with KOA participated in the study. Of these, 30 participated in the validation process of the pre-final version of the FreKAQ. One hundred four were evaluated with the FreKAQ, the Numeric Pain Rating Scale (NPRS), the Pain Catastrophizing Scale (PCS), the International Knee Documentation Committee (IKDC), and the 36-item short-form survey (SF-36). The construct validity was tested using Spearman's correlation coefficient, and ceiling and floor effects were calculated. A subsample of 54 participants participated in the reproducibility assessment. Internal consistency was calculated using Cronbach's alpha. Reproducibility was assessed using the test-retest model using the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimum detectable change (MDC).

RESULTS

the FreKAQ showed a favorable correlation with the construct's intensity and catastrophizing related to pain and activities of daily living (p < 0.01). It also had the functional capacity, pain, social aspects, and emotional aspects of the SF-36 (p < 0.05). Additionally, it presented excellent ICC (0.91) and adequate internal consistency (0.91) with the SEM and MDC scores, respectively, 2.86 and 7.94. There were no ceiling or floor effects.

CONCLUSION

The FreKAQ showed adequate measurement properties in individuals with KOA, indicating its use as an evaluative measure of body perception of the knee.

Disrupted topological organization of brain connectome in patients with chronic low back related leg pain and clinical correlations

Chronic pain is associated with persistent alterations in brain structure and function. However, existing research has not fully explored the relationship between brain network topological properties and clinical symptoms in patients with chronic low back-related leg pain (cLBLP). In this study, we collected resting-state functional and structural magnetic resonance imaging data, along with clinical symptom evaluation data, from 32 cLBLP patients and 31 healthy controls. A large-scale complex network analysis was conducted to evaluate the global and nodal topological properties of functional and structural brain networks. Statistical analyses were performed to determine the associations between network properties and clinical variables. The results showed significant alterations in both global and nodal topological properties of functional and structural brain networks in cLBLP patients compared to healthy controls. Additionally, a direct correlation was found between structural network properties and spatial discrimination ability, measured by two-point tactile discrimination values, while no significant association was observed between functional connectivity and spatial discrimination. This study demonstrates that cLBLP patients exbibit a decreased local efficiency of functional connectivity network and increased compensatory global efficiency of structural connectivity network. Notably, alterations in the structural connectome, rather than the functional connectome, play a more significant role in deterioration of foot tactile spatial acuity in cLBLP patients. Trial registration: This trial was registered in the Chinese Clinical Trial Registry with the registration number ChiCTR2200055321 on 2022-01-06.

Body awareness disturbances in patients with low back pain: a systematic review

BACKGROUND

The pain-neuroscience literature has recently emphasized body perception or awareness. Impaired body perception results have been reported in many different chronic pain problems. Studies have reported that individuals with low back pain (LBP) also have body perception disturbances related to the lumbar spine.

OBJECTIVES

This review aimed to determine the evidence that body awareness alterations in individuals with LBP.

DESIGN

Systematic review.

METHOD

Studies were searched in PubMed, Cochrane Library, and Pedro databases up to January 2021. Each database was searched independently, according to a specific iteration research string. The protocol record of the systematic review was entered into the PROSPERO system.

RESULTS

Nine studies were included in this research. We found evidence to support more perceptual impairments in patients with LBP than healthy counterparts. In addition, the results of the studies showed an association between disrupted body awareness and pain severity, pain catastrophizing, and disability.

CONCLUSIONS

Body perception disturbances in LBP seem to be a promising path that needs to be further explored, with the ultimate goal of developing treatment contents targeting body awareness as a more comprehensive and valid evaluation and therapeutic method.

TRIAL REGISTRATION

The registration number was CRD42021235934.

Body Image Measured via the Fremantle Awareness Questionnaire in Individuals With and Without Pain: A Systematic Review and Meta-Analysis

Research suggests that pain negatively affects body image, and body image may also influence reported pain levels. This review aims to summarize the literature on differences in body image distortion between individuals with pain compared to pain-free individuals. The review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 statement and an a priori preregistered protocol. The literature was searched using 5 electronic databases. Studies assessing body image with the Fremantle Awareness Questionnaire (FAQ) in individuals with and without pain were eligible for inclusion. Screening and selection of eligible studies were performed by independent reviewers. Methodological quality was assessed with the Joanna Briggs Institute critical appraisal tool. Meta-analyses, meta-correlations, and metamean analyses were performed using random-effect models. The primary outcome was the FAQ score; secondary outcomes were reported pain variables. Data from individuals with pain (n = 2277) and without pain (n = 615) were summarized. Significant body image distortions were found in individuals with pain compared to individuals without pain. Compared to pain-free individuals, the pain group rated significantly higher in the FAQ when experiencing back pain (standardized mean differences=1.33, 95% confidence interval=.88-1.77) or other body parts (standardized mean differences=1.25, 95% confidence interval=.51-1.99). The results of meta-correlation analyses confirmed the positive relationship between body image distortion and pain intensity (r = .31), pain at rest (r = .31), or pain during movement (r = .36), but not for pain duration. A difference in mean FAQ results was observed between individuals with pain in different areas (knee and back). PERSPECTIVE: This review confirms differences in body image distortion between pain and pain-free individuals. Pain intensity was correlated with altered body perception, but not pain duration. A moderate correlation was observed between body image distortion and reported pain variables. Body image was more impaired by knee pain than back pain. REGISTERED PROTOCOL AT PROSPERO: CRD42022309937; https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022309937.

Unraveling the Left-Right Judgment Task in Chronic Low Back Pain: Insights Through Behavioral, Electrophysiological, Motor Imagery, and Bodily Disruption Perspectives

Bodily disruptions have been consistently demonstrated in individuals with chronic low back pain. The performance on the left-right judgment task has been purposed as an indirect measure of the cortical proprioceptive representation of the body. It has been suggested to be dependent on implicit motor imagery, although the available evidence is conflicting. Hence, the aim of this case-control observational study was to examine the performance (accuracy and reaction times) and event-related potentials while performing the left-right judgment task for back and hand images in individuals with chronic low back pain versus healthy controls, along with its relationship with self-reported measurements and quantitative sensory testing. While self-reported data suggested bodily disruptions in the chronic low back pain sample, this was not supported by quantitative sensory testing. Although both groups displayed the same performance, our results suggested an increased attentional load on participants with chronic low back pain to achieve equal performance, measured by a higher N1 peak amplitude in occipital electrodes, especially when the effect of contextual images arises. The absence of differences in the reaction times for the left-right judgment task between both groups, along with inconsistencies in self-reported and quantitative sensory testing data, could question the involvement of implicit motor imagery in solving the task. In conclusion, our results suggest disrupted attentional processing in participants with chronic low back pain to solve the left-right judgment task. PERSPECTIVE: Although there are no differences in the performance of the left-right judgment task (hits, reaction times) between chronic low back pain patients and controls, the analysis of event-related potentials revealed that patients require a higher cognitive load, measured by N1 peak amplitude.

"My Hand Is Different": Altered Body Perception in Stroke Survivors with Chronic Pain

BACKGROUND

Chronic pain and body perception disturbance are common following stroke. It is possible that an interaction exists between pain and body perception disturbance, and that a change in one may influence the other. We therefore investigated the presence of body perception disturbance in individuals with stroke, aiming to determine if a perceived change in hand size contralateral to the stroke lesion is more common in those with chronic pain than in those without.

METHODS

Stroke survivors (N = 523) completed an online survey that included: stroke details, pain features, and any difference in perceived hand size post-stroke.

RESULTS

Individuals with stroke who experienced chronic pain were almost three times as likely as those without chronic pain to perceive their hand as now being a different size (OR = 2.895; 95%CI 1.844, 4.547). Further, those with chronic pain whose pain included the hand were almost twice as likely to perceive altered hand size than those whose pain did not include the hand (OR = 1.862; 95%CI 1.170, 2.962). This was not influenced by hemisphere of lesion (p = 0.190).

CONCLUSIONS

The results point to a new characteristic of chronic pain in stroke, raising the possibility of body perception disturbance being a rehabilitation target to improve function and pain-related outcomes for stroke survivors.

Prediction and trend of tactile acuity, pain and disability in acute LBP: a six-month prospective cohort study

Background

Chronic back pain is known to be associated with altered tactile acuity. Tactile acuity is measured using the Two-Point Discrimination (TPD) test in both clinical and research settings. In subjects with chronic low back pain, the TPD threshold (TPDT) is increased and is associated with persistent pain. It remains unknown, however, whether TPDT is also altered in cases of clinical acute pain, or whether it could be used as a predictor of future pain and disability at an early stage of LBP.

The main objective of this study was to investigate the predictive value of baseline TPDT for pain and disability at 3 and 6 months after the onset of acute LBP. The TPDT in acute low back pain (LBP) and the development of TPDT over 6 months has also been assessed.

Methods

LBP participants (n = 124) with acute LBP (< 4 weeks) were included. Subjects were examined within 4 weeks of pain onset and followed-up after 3 and 6 months of pain onset. Horizontal and vertical TPDTs of the lower back were collected. Linear mixed models were subsequently used to evaluate the association of TPDT with pain and disability over time.

Results

The vertical TPDT showed a mean (SD) of 4.9 cm (1.6) and the horizontal TPDT a mean (SD) of 6.0 cm (1.5) at baseline. The vertical TPDT altered from baseline up to 6 months from 4.9 to 4.6 cm and the horizontal TPDT from 6.0 to 5.4 cm. The association between the TPDT and the Oswestry Disability Index (ODI) after 6 months was moderate. Linear mixed models revealed no association between TPDT, pain and disability over the progression of LBP.

Conclusion

TPDTs appear to be raised in subjects with acute LBP. However, our study revealed no predictive capability of the TPDT for disability and pain. No comparisons are possible in the absence of similar studies, indicating the need for further research is in this area.

Sensorimotor and body perception assessments of nonspecific chronic low back pain: a cross-sectional study

BACKGROUND

Low back pain (LBP) is one of the most common musculoskeletal disorders, causing significant personal and social burden. Current research is focused on the processes of the central nervous system (particularly the sensorimotor system) and body perception, with a view to developing new and more efficient ways to treat chronic low back pain (CLBP). Several clinical tests have been suggested that might have the ability to detect alterations in the sensorimotor system. These include back-photo assessment (BPA), two-point discrimination (TPD), and the movement control tests (MCT). The aim of this study was to determine whether the simple clinical tests of BPA, TPD or MCT are able to discriminate between nonspecific CLBP subjects with altered body perception and healthy controls.

METHODS

A cross-sectional study was conducted. At one point in time, 30 subjects with CLBP and 30 healthy controls were investigated through using BPA, TPD and MCT on the lower back. Correlations among the main covariates and odds ratios for group differences were calculated.

RESULTS

MCT showed an odds ratio for the presence of CLBP of 1.92, with a statistically significant p-value (0.049) and 95%CI. The TPD and BPA tests were unable to determine significant differences between the groups.

CONCLUSIONS

Of the three tests investigated, MCT was found to be the only suitable assessment to discriminate between nonspecific CLBP subjects and healthy controls. The MCT can be recommended as a simple clinical tool to detect alterations in the sensorimotor system of nonspecific CLBP subjects. This could facilitate the development of tailored management strategies for this challenging LBP subgroup. However, further research is necessary to elucidate the potential of all the tests to detect alterations in the sensorimotor system of CLBP subjects.

TRIAL REGISTRATION

No trial registration was needed as the study contains no intervention. The study was approved by the Swiss Ethics Commission of Northwest and Central Switzerland (EKNZ) reference number 2015-243.

Laterality judgements in patients with frequent episodic migraine

INTRODUCTION

Migraine is a cyclic disorder but also a chronic pain condition. Left-right recognition tasks have been shown to be impaired in patients with chronic pain.

OBJECTIVES

To investigate whether laterality judgements of migraine patients depend on the status within the migraine cycle.

METHODS

34 episodic migraine patients completed a laterality recognition task on 30 consecutive days using the Recognise™ software. Reaction time and number of mistakes of recognising the left or right side of a face or neck movements to the right or left were recorded and analysed longitudinally. Ictal days (48 h and 24 h prior to the attack; during the headache phase; 24 h after the attack) were contrasted against interictal days using repeated measures ANOVAs. 4 headache-free controls served to investigate the natural fluctuation over time and to compare migraine versus non-migraine data in a secondary exploratory analysis.

RESULTS

1691 data sets from migraine patients and 183 from control participants were included in the analyses. Results indicated that performance varied throughout the migraine cycle but only showed a clear pattern of prolonged response times for images of movements to the right (F(4,1690) = 2.412; p = 0.047), while data for frequency of correct answers and for the left side remained inconclusive. Migraine patients had a reduced frequency of correct answers (right: F(1,1873) = 11.426; p = 0.001; left: F(1,1873) = 5.873; p = 0.015). Response times where unaffected. Laterality judgements were not correlated with the dominant headache side.

CONCLUSIONS

The current data shows that laterality judgements can depend on the status within the migraine cycle. Laterality judgements of migraine patients where comparable to other chronic pain conditions.