The cartography of pain: the evolving contribution of pain maps

Data-driven identification of distinct pain drawing patterns and their association with clinical and psychological factors: a study of 21,123 patients with spinal pain

ABSTRACT

The variability in pain drawing styles and analysis methods has raised concerns about the reliability of pain drawings as a screening tool for nonpain symptoms. In this study, a data-driven approach to pain drawing analysis has been used to enhance the reliability. The aim was to identify distinct clusters of pain patterns by using latent class analysis (LCA) on 46 predefined anatomical areas of a freehand digital pain drawing. Clusters were described in the clinical domains of activity limitation, pain intensity, and psychological factors. A total of 21,123 individuals were included from 2 subgroups by primary pain complaint (low back pain (LBP) [n = 15,465]) or midback/neck pain (MBPNP) [n = 5658]). Five clusters were identified for the LBP subgroup: LBP and radiating pain (19.9%), radiating pain (25.8%), local LBP (24.8%), LBP and whole leg pain (18.7%), and widespread pain (10.8%). Four clusters were identified for the MBPNP subgroup: MBPNP bilateral posterior (19.9%), MBPNP unilateral posterior + anterior (23.6%), MBPNP unilateral posterior (45.4%), and widespread pain (11.1%). The clusters derived by LCA corresponded to common, specific, and recognizable clinical presentations. Statistically significant differences were found between these clusters in every self-reported health domain. Similarly, for both LBP and MBPNP, pain drawings involving more extensive pain areas were associated with higher activity limitation, more intense pain, and more psychological distress. This study presents a versatile data-driven approach for analyzing pain drawings to assist in managing spinal pain.

Reliability of the Pen-on-Paper Pain Drawing Analysis Using Different Scanning Procedures

INTRODUCTION

Pen-on-paper pain drawing are an easily administered self-reported measure that enables patients to report the spatial distribution of their pain. The digitalization of pain drawings has facilitated the extraction of quantitative metrics, such as pain extent and location. This study aimed to assess the reliability of pen-on-paper pain drawing analysis conducted by an automated pain-spot recognition algorithm using various scanning procedures.

METHODS

One hundred pain drawings, completed by patients experiencing somatic pain, were repeatedly scanned using diverse technologies and devices. Seven datasets were created, enabling reliability assessments including inter-device, inter-scanner, inter-mobile, inter-software, intra- and inter-operator. Subsequently, the automated pain-spot recognition algorithm estimated pain extent and location values for each digitized pain drawing. The relative reliability of pain extent analysis was determined using the intraclass correlation coefficient, while absolute reliability was evaluated through the standard error of measurement and minimum detectable change. The reliability of pain location analysis was computed using the Jaccard similarity index.

RESULTS

The reliability analysis of pain extent consistently yielded intraclass correlation coefficient values above 0.90 for all scanning procedures, with standard error of measurement ranging from 0.03% to 0.13% and minimum detectable change from 0.08% to 0.38%. The mean Jaccard index scores across all dataset comparisons exceeded 0.90.

CONCLUSIONS

The analysis of pen-on-paper pain drawings demonstrated excellent reliability, suggesting that the automated pain-spot recognition algorithm is unaffected by scanning procedures. These findings support the algorithm's applicability in both research and clinical practice.

Do metrics derived from self-reported and clinician-reported pain drawings agree for individuals with chronic low back pain?

BACKGROUND

Clinicians commonly use pain drawings to define the spatial extent and location of a person's pain, but limited research has investigated who should perform the drawing.

OBJECTIVES

To establish the inter-rater reliability of pain extent and location derived from three sets of pain drawings for people with chronic low back pain: one self-reported and two clinician-reported. Additionally, convergent validity of pain extent was assessed using the same dataset.

DESIGN

Repeated-measures cross-sectional study.

METHOD

Fifteen patients with chronic low back pain and a pool of eight clinicians were involved to assess the reliability of pain extent and location extracted by self-report and clinician-reported pain drawings. Inter-rater reliability of pain extent was computed using intraclass correlation coefficients (ICC) and Bland Altman analysis. Convergent validity of pain extent was assessed using Spearman's rank correlation. Inter-rater reliability of pain location was assessed using the Jaccard similarity index.

RESULTS

The inter-reliability analysis for pain extent, derived from self-reported and clinician-reported pain drawings, revealed ICC scores ranging from 0.39 to 0.51, all with wide confidence intervals. The mean Jaccard similarity indexes computed for pain location ranged from 0.60 to 0.65. Moderate to good correlation was found for pain extent derived by the sets of pain drawings.

CONCLUSIONS

Inter-rater reliability of pain extent and pain location derived from self-reported and clinician-reported pain drawings is poor in patients with chronic low back pain. The lack of reliability is also confirmed when considering only clinician-reported PDs. The convergent validity analysis of pain extent revealed that the two pain drawing approaches measure a similar construct.

Musculoskeletal Pain in Family Caregivers: Does a Therapeutic Physical Program in Primary Care Work? A Randomized Controlled Trial

Background: Family caregivers play a crucial role in the overall healthcare system and in our society. The elderly population is significantly increasing, which creates a high demand for family caregivers. Few studies have investigated the impact of caregiving on musculoskeletal pain or proposed an active approach for dealing with it. Objectives: To determine and characterize musculoskeletal pain in female family caregivers (FFCs) and assess the effects of adding a therapeutic exercise program to a family caregiver care program (FCCP) on the quality of life, physical conditions, and psychological well-being of FFCs. Methods: A multicenter randomized controlled clinical trial was conducted with 68 FFCs recruited in two public healthcare areas. The intervention and control groups received the same conventional FCCP for 6 h across 4 sessions. The intervention group received an additional 36 sessions of physical therapeutic exercise (PTE) program over 12 weeks. Results: All caregivers reported having pain in particular locations. Lower back pain and neck pain were the locations most frequently cited, with a prevalence of 69.4% and 56.7%, respectively. In total, 80% of participants presented moderate pain intensity. The intervention group showed a significant decrease in the intensity of the pain (p < 0.001), as well as in anxiety, depression, subjective burden perception (p < 0.01), and quality-of-life variables, including MCS (mental component summary) (p < 0.05) and PCS (physical component summary) (p < 0.001). Conclusions: A PTE program improved the musculoskeletal pain of FFCs in a clinically relevant way. The caregivers who improved the most were those who initially presented the most intense pain, had the greatest levels of disability, and had the lowest quality of life.

Quantification of Digital Body Maps for Pain: Development and Application of an Algorithm for Generating Pain Frequency Maps

BACKGROUND

Pain is an unpleasant sensation that signals potential or actual bodily injury. The locations of bodily pain can be communicated and recorded by freehand drawing on 2D or 3D (manikin) surface maps. Freehand pain drawings are often part of validated pain questionnaires (eg, the Brief Pain Inventory) and use 2D templates with undemarcated body outlines. The simultaneous analysis of drawings allows the generation of pain frequency maps that are clinically useful for identifying areas of common pain in a disease. The grid-based approach (dividing a template into cells) allows easy generation of pain frequency maps, but the grid's granularity influences data capture accuracy and end-user usability. The grid-free templates circumvent the problem related to grid creation and selection and provide an unbiased basis for drawings that most resemble paper drawings. However, the precise capture of drawn areas poses considerable challenges in producing pain frequency maps. While web-based applications and mobile-based apps for freehand digital drawings are widely available, tools for generating pain frequency maps from grid-free drawings are lacking.

OBJECTIVE

We sought to provide an algorithm that can process any number of freehand drawings on any grid-free 2D body template to generate a pain frequency map. We envisage the use of the algorithm in clinical or research settings to facilitate fine-grain comparisons of human pain anatomy between disease diagnosis or disorders or as an outcome metric to guide monitoring or discovery of treatments.

METHODS

We designed a web-based tool to capture freehand pain drawings using a grid-free 2D body template. Each drawing consisted of overlapping rectangles (Scalable Vector Graphics <rect> elements) created by scribbling in the same area of the body template. An algorithm was developed and implemented in Python to compute the overlap of rectangles and generate a pain frequency map. The utility of the algorithm was demonstrated on drawings obtained from 2 clinical data sets, one of which was a clinical drug trial (ISRCTN68734605). We also used simulated data sets of overlapping rectangles to evaluate the performance of the algorithm.

RESULTS

The algorithm produced nonoverlapping rectangles representing unique locations on the body template. Each rectangle carries an overlap frequency that denotes the number of participants with pain at that location. When transformed into an HTML file, the output is feasibly rendered as a pain frequency map on web browsers. The layout (vertical-horizontal) of the output rectangles can be specified based on the dimensions of the body regions. The output can also be exported to a CSV file for further analysis.

CONCLUSIONS

Although further validation in much larger clinical data sets is required, the algorithm in its current form allows for the generation of pain frequency maps from any number of freehand drawings on any 2D body template.

Pain extent is associated with Central Sensitization Inventory but not widespread pressure pain sensitivity or psychological variables in women with fibromyalgia

OBJECTIVE

To investigate the relationship between pain extent, as a clinical sign of central sensitization, and clinical, psychological, and pressure sensitivity in women with fibromyalgia syndrome (FMS).

METHOD

In this study, 126 females with FMS completed demographic (age, gender, body mass index, height, weight), clinical (pain history, and pain intensity at rest and during daily living activities), psychological (depression and anxiety levels), and neurophysiological [pressure pain threshold (PPT)] assessments. The Central Sensitization Inventory (CSI) was also used to collect self-reported symptoms of sensitization. Pain extent and frequency maps were obtained from pain drawings using customized software. After conducting a multivariable correlation analysis to determine the relationships between variables, a stepwise linear regression model analysis was performed to identify variables associated with pain extent.

RESULTS

Pain extent was positively associated with age (r = 0.17), years with pain (r = 0.27), pain during daily life activities (r = 0.27), and CSI (r = 0.42) (all p < 0.05). The stepwise regression analysis revealed that 27.8% of the pain extent was explained by CSI, age, and years with pain.

CONCLUSIONS

This study found that larger pain extent was associated with self-reported outcomes, i.e. CSI, but not neurophysiological outcomes, i.e. PPTs, of sensitization in women with FMS. Older age and a longer history with pain symptoms were also associated with larger pain extent.

Novel Software for Pain Drawing Analysis

Introduction

Pain drawings (PDs) are an important component of the assessment of a patient with pain. Although analog pain drawings (APDs), such as pen-on-paper drawings, have been extensively used in clinical assessment and clinical research, there is a lack of digital pain drawing (DPD) software that would be able to quantify and analyze the digital pain distribution obtained by the patients. The aim of this work is to describe a method that can quantify the extent and location of pain through novel custom-built software able to analyze data from the digital pain drawings obtained from the patients.

Methods

The application analysis and software specifications were based on the information gathered from the literature, and the programmers created the custom-built software according to the published needs of the pain scientific community.

Results

We developed a custom-built software named “Pain Distribution,” which, among others, automatically calculates the number of the pixels the patient has chosen and therefore quantifies the pain extent, provides the frequency distribution from a group of images, and has the option to select the threshold over which the patient is considered with central sensitization (CS). Additionally, it delivers results and statistics for both every image and the frequency distribution, providing mean values, standard deviations, and CS indicators, as well as the ability to export them in *.txt file format for further analysis.

Conclusion

A novel Pain Distribution application was developed, freely available for use in any setting, clinical, research, or academic.

Development and Validation of the Pain and State of Health Inventory (PHI): Application for the Perioperative Setting

Currently, general measurements and evaluations of the quality of recovery are difficult because no adequate measuring tools are available. Therefore, there is an urgent need for a universal tool that assesses patient-relevant criteria-postoperative pain, state of health, and somatic parameters. For this purpose, a pain and state of health inventory (PHI, Schmerz- und Befindlichkeitsinventar (SBI) in German) has been developed. In this study, we describe its development and validation. The development phase was led by an expert panel and was divided into three subphases: determining the conceptual structure, testing the first editions, and adjusting the inventory for a finalized edition. For the purpose of validation, the PHI was filled in by 132 patients who have undergone total knee replacement and was analyzed using principal component analysis. Construct validity was tested by correlating the items with validated questionnaires. The results showed that the inventory can test pain, state of health, and somatic parameters with great construct validity. Furthermore, the inventory is accepted by patients, map changes, and supports to initiate adequate treatment. In conclusion, the PHI is a universal tool that can be used to assess the quality of recovery in the perioperative setting and allow immediate intervention.

Clinical Significance and Diagnostic Value of Pain Extent Extracted from Pain Drawings: A Scoping Review

The current scoping review aimed to map current literature investigating the relationship between pain extent extracted from pain drawings with clinical, psychological, and psycho-physiological patient-reported outcome measures in people with pain. Electronic databases were searched for cross-sectional cohort studies that collected pain drawings using digital technology or a pen-on-paper approach and assessed for correlations between pain extent and clinical, psychological or psycho-physical outcomes. Data were extracted by two different reviewers. The methodological quality of studies was assessed using the Newcastle–Ottawa Quality Assessment Scale. Mapping of the results included: 1, description of included studies; 2, summary of results; and 3, identification of gaps in the existing literature. Eleven cross-sectional cohort studies were included. The pain disorders considered were heterogeneous, ranging from musculoskeletal to neuropathic conditions, and from localized to generalized pain conditions. All studies included pain and/or pain-related disability as clinical outcomes. Psychological outcomes included depression and anxiety, kinesiophobia and catastrophism. Psycho-physical measures included pressure or thermal pain thresholds. Ten studies were considered of high methodological quality. There was heterogeneity in the associations between pain extent and patient-reported outcome measures depending on the pain condition. This scoping review found that pain extent is associated with patient-reported outcome measures more so in patients presenting with musculoskeletal pain, e.g., neck pain or osteoarthritis, rather than for those with neuropathic pain or headache.

Therapeutic Sensations: A New Unifying Concept

Physical sensations of tingling, warmth, dull pain, and heaviness are a common phenomenon in mind-body interventions, such as acupuncture, hypnotherapy, osteopathy, qigong, meditation, and progressive muscle relaxation. Even though there are striking parallels between sensations produced by many different interventions, no attempt has yet been made to understand them from a unifying perspective that combines information from different therapies and practices. Therefore, this narrative systematic review introduces the concept of therapeutic sensations and summarizes studies of their sensory quality, bodily topography, and the meaning that patients attach to them. Furthermore, it highlights the essential role of therapeutic sensations in the development of vital energy concepts, such as qi, prana, pneuma, and orgone, in various traditional medicine systems, body-oriented psychotherapy, and so-called energy medicine. Finally, the assessment of therapeutic sensations may help to gain a deeper understanding of such concepts, finding a common language between scientists, patients and practitioners, and bridging the wide gap between materialistic and vitalistic views.

From Paper to Digital Applications of the Pain Drawing: Systematic Review of Methodological Milestones

Background

In a pain drawing (PD), the patient shades or marks painful areas on an illustration of the human body. This simple yet powerful tool captures essential aspects of the subjective pain experience, such as localization, intensity, and distribution of pain, and enables the extraction of meaningful information, such as pain area, widespreadness, and segmental pattern. Starting as a simple pen-on-paper tool, PDs are now sophisticated digital health applications paving the way for many new and exciting basic translational and clinical applications.

Objective

Grasping the full potential of digital PDs and laying the groundwork for future medical PD apps requires an understanding of the methodological developments that have shaped our current understanding of uses and design. This review presents methodological milestones in the development of both pen-on-paper and digital PDs, thereby offering insight into future possibilities created by the transition from paper to digital.

Methods

We conducted a systematic literature search covering PD acquisition, conception of PDs, PD analysis, and PD visualization.

Results

The literature search yielded 435 potentially relevant papers, from which 53 methodological milestones were identified. These milestones include, for example, the grid method to quantify pain area, the pain-frequency maps, and the use of artificial neural networks to facilitate diagnosis.

Conclusions

Digital technologies have had a significant influence on the evolution of PDs, whereas their versatility is leading to ever new applications in the field of medical apps and beyond. In this process, however, there is a clear need for better standardization and a re-evaluation of methodological and technical limitations that no longer apply today.

Abstract Animations for the Communication and Assessment of Pain in Adults: Cross-Sectional Feasibility Study

BACKGROUND

Pain is the most common physical symptom requiring medical care, yet the current methods for assessing pain are sorely inadequate. Pain assessment tools can be either too simplistic or take too long to complete to be useful for point-of-care diagnosis and treatment.

OBJECTIVE

The aim was to develop and test Painimation, a novel tool that uses graphic visualizations and animations instead of words or numeric scales to assess pain quality, intensity, and course. This study examines the utility of abstract animations as a measure of pain.

METHODS

Painimation was evaluated in a chronic pain medicine clinic. Eligible patients were receiving treatment for pain and reported pain more days than not for at least 3 months. Using a tablet computer, participating patients completed the Painimation instrument, the McGill Pain Questionnaire (MPQ), and the PainDETECT questionnaire for neuropathic symptoms.

RESULTS

Participants (N=170) completed Painimation and indicated it was useful for describing their pain (mean 4.1, SE 0.1 out of 5 on a usefulness scale), and 130 of 162 participants (80.2%) agreed or strongly agreed that they would use Painimation to communicate with their providers. Animations selected corresponded with pain adjectives endorsed on the MPQ. Further, selection of the electrifying animation was associated with self-reported neuropathic pain (r=.16, P=.03), similar to the association between neuropathic pain and PainDETECT (r=.17, P=.03). Painimation was associated with PainDETECT (r=.35, P<.001).

CONCLUSIONS

Using animations may be a faster and more patient-centered method for assessing pain and is not limited by age, literacy level, or language; however, more data are needed to assess the validity of this approach. To establish the validity of using abstract animations ("painimations") for communicating and assessing pain, apps and other digital tools using painimations will need to be tested longitudinally across a larger pain population and also within specific, more homogenous pain conditions.

Designing a Tablet-Based Software App for Mapping Bodily Symptoms: Usability Evaluation and Reproducibility Analysis

Background

Symptom drawings are widely used as a qualitative and quantitative method of assessing pain symptoms for both clinical and research purposes. As electronic drawings offer many advantages over classical pen-and-paper drawings, the last years have seen a shift toward tablet-based acquisition of symptom drawings. However, software that is used in clinical care requires special attention to usability aspects and design to provide easy access for physically impaired or elderly patients.

Objective

The aims of this project were to develop a new tablet-based software app specifically designed to collect patients’ and doctors’ drawings of pain and related bodily symptoms and test it for usability in 2 samples of chronic pain patients (Aim 1) and their treating doctors (Aim 2) as well as for test-retest reliability (Aim 3).

Methods

In 2 separate studies, symptom drawings from 103 chronic pain patients and their treating doctors were collected using 2 different versions of the app. Both patients and doctors evaluated usability aspects of the app through questionnaires. Results from study 1 were used to improve certain features of the app, which were then evaluated in study 2. Furthermore, a subgroup of 25 patients in study 2 created 2 consecutive symptom drawings for test-retest reproducibility analysis. Usability of both app versions was compared, and reproducibility was calculated for symptom extent, number of symptom clusters, and the whole symptom pattern.

Results

The changes we made to the app and the body outline led to significant improvements in patients’ usability evaluation regarding the identification with the body outline (P=.007) and the evaluation of symptom depth (P=.02), and the overall difficultness of the drawing process (P=.003) improved significantly. Doctors’ usability evaluation of the final app showed good usability with 75.63 (SD 19.51) points on the System Usability Scale, Attrakdiff 2 scores from 0.93 to 1.41, and ISONORM 9241/10 scores from −0.05 to 1.80. Test-retest analysis showed excellent reproducibility for pain extent (intraclass correlation coefficient, ICC=0.92) and good results for the number of symptom clusters (ICC=0.70) and a mean overlap of 0.47 (Jaccard index).

Conclusions

We developed a tablet-based symptom drawing app and improved it based on usability assessment in a sample of chronic pain patients and their treating doctors. Increases in usability of the improved app comprised identification with the body outline, symptom depth evaluation, and difficultness of the drawing process. Test-retest reliability of symptom drawings by chronic pain patients showed fair to excellent reproducibility. Patients’ usability evaluation is an important factor that should not be neglected when designing apps for mobile or eHealth apps.

Impaired sleep predicts onset of low back pain and burnout symptoms: evidence from a three-wave study

In a three-wave questionnaire study of 405 working participants, who were initially free of low back pain (LBP) and emotional exhaustion, sleep problems were evaluated as a potential risk factor for the development of LBP and burnout up to three years later. Prospective risk paths were compared between the sexes and between two age-groups (18 to 45 years and older than 45 years). A longitudinal structural equation model showed a good fit with empirical data (RMSEA = .04, SRMR = .06, CFI = .97). Prospective risk paths between the latent constructs showed sleep problems to significantly predict self-reported LBP (β = .15, p = .011) and burnout (β = .24, p < .001) two years later. Sleep problems also predicted the occurrence of burnout three years later (β = .18, p = .002). Sleep-related risk of burnout after two years was greater in older than younger participants (β_older = .42 vs. β_younger = .13, p < .001). Sleep problems seem to precede LBP and burnout in working individuals. Health promotion initiatives should use sleep quality as an important early risk indicator, and interventions should focus on promoting better quality sleep, in an attempt to reduce the incidence of LBP and burnout.

Test-retest Reliability in Reporting the Pain Induced by a Pain Provocation Test: Further Validation of a Novel Approach for Pain Drawing Acquisition and Analysis

BACKGROUND

Pain drawings (PD) are frequently used in research to illustrate the pain response to pain provocation tests. However, there is a lack of data on the reliability in defining the extent and location of pain. We investigated the test-retest reliability in reporting an acute painful sensation induced by a pain provocation test using a novel approach for PD acquisition and analysis in healthy volunteers.

METHODS

Forty healthy volunteers participated. Each participant underwent 2 upper limb neurodynamic tests 1 (ULNT1), once to the point of pain onset (PO) and once until the point of submaximal pain (SP). After each ULNT1, participants completed 2 consecutive PD with an interval of 1 minute. Custom software was used to quantify the pain extent and analyze the pain overlap. The test-retest reliability of pain extent was examined using Intraclass Correlation Coefficient (ICC _2,1 ) and Bland-Altman plots. Pain location reliability was examined using the Jaccard similarity coefficient (JSC).

RESULTS

The ICC values for PO and SP were 0.98 (95% CI: 0.96-0.99) and 0.97 (95% CI: 0.95-0.98), respectively. The mean difference and 95% limits of agreement (± 1.96 SD) in the Bland-Altman plots were 14 pixels (-1080;1110) for PO, and 145 (-1610;1900) for SP. The median JSCs (Q1;Q3) were 0.73 (0.64;0.80) for PO and 0.76 (0.65;0.79) for SP.

CONCLUSIONS

Pain drawings is a reliable instrument to investigate pain extent and pain location in healthy individuals experiencing an acute painful sensation induced by a pain provocation test.

Validity of pain drawings for predicting psychological status outcome in patients with recurrent or chronic low back pain

OBJECTIVES

To investigate the association between baseline pain drawings and future psychological status, and estimate the prognostic value of pain drawing assessment for predicting somatization, distress, and depression at one-year follow-up, in patients with recurrent or chronic low back pain (RCLBP).

METHODS

This was a multi-center prospective cohort study of 138 patients with RCLBP. Participating patients completed at baseline and one-year follow-up: a blank pain drawing; the Modified Somatic Perceptions Questionnaire; modified Zung Depression Scale; and Distress and Risk Assessment Method. Pain drawings were analyzed quantitatively using the Pain Sites Score (PSS) and Simple Body Region (SBR) method. The association between baseline pain drawing assessment and one-year psychological status was estimated using correlation and Relative Risk (RR) statistics.

RESULTS

We obtained complete data from 81 patients (59%). Psychological status and pain drawings did not differ significantly between completers and non-completers. Pain drawing area at baseline was associated with depression and somatization at one-year follow-up (Spearman's Rho 0.25, P = 0.022; 0.31 P = 0.006, respectively). Stronger associations resulted from analyses using the PSS, compared with the SBR. Patients with abnormal PSS pain drawings at baseline had significantly greater RR of depression (RR 6.1, 95% CI 1.1, 33.5), somatization (RR 4.1, 95% CI 1.7, 9.9) and distress (RR 6.8, 95% CI 1.9, 25.3) at one-year follow-up.

DISCUSSION

These results provide the first evidence that abnormal baseline pain drawings predict greater risk of abnormal psychological states or poor psychological outcome at one-year follow-up, in patients with RCLBP.

Pictures of pain: their contribution to the neuroscience of empathy

The study of empathy, a translation of the term 'Einfühlung', originated in 19th century Germany in the sphere of aesthetics, and was followed by studies in psychology and then neuroscience. During the past decade the links between empathy and art have started to be investigated, but now from the neuroscientific perspective, and two different approaches have emerged. Recently, the primacy of the mirror neuron system and its association with automaticity and imitative, simulated movement has been envisaged. But earlier, a number of eminent art historians had pointed to the importance of cognitive responses to art; these responses might plausibly be subserved by alternative neural networks. Focusing here mainly on pictures depicting pain and evoking empathy, both approaches are considered by summarizing the evidence that either supports the involvement of the mirror neuron system, or alternatively suggests other neural networks are likely to be implicated. The use of such pictures in experimental studies exploring the underlying neural processes, however, raises a number of concerns, and suggests caution is exercised in drawing conclusions concerning the networks that might be engaged. These various networks are discussed next, taking into account the affective and sensory components of the pain experience, before concluding that both mirror neuron and alternative neural networks are likelyto be enlisted in the empathetic response to images of pain. A somewhat similar duality of spontaneous and cognitive processes may perhaps also be paralleled in the creation of such images. While noting that some have repudiated the neuroscientific approach to the subject, pictures are nevertheless shown here to represent an unusual but invaluable tool in the study of pain and empathy.

Building a diagnostic algorithm on localized neuropathic pain (LNP) and targeted topical treatment: focus on 5% lidocaine-medicated plaster

Within the broad definition of neuropathic pain, the refinement of clinical diagnostic procedures has led to the introduction of the concept of localized neuropathic pain (LNP). It is characterized by consistent and circumscribed area(s) of maximum pain, which are associated with negative or positive sensory signs and/or spontaneous symptoms typical of neuropathic pain. This description outlines the clinical features (currently lacking in guidelines and treatment recommendations) in patients for whom topical targeted treatment with 5% lidocaine-medicated plaster is suggested as first-line therapy. Few epidemiologic data are present in the literature but it is generally estimated that about 60% of neuropathic pain conditions are localized, and therefore identifiable as LNP. A mandatory clinical criterion for the diagnosis of LNP is that signs and symptoms must be present in a clearly identified and defined area(s). Cartographic recordings can help to define each area and to assess variations. The diagnosis of LNP relies on careful neurological examination more than on pain questionnaires, but it is recognized that they can be extremely useful for recording the symptom profiles and establishing a more targeted treatment. The most widely studied frequent/relevant clinical presentations of LNP are postherpetic neuralgia, diabetic neuropathy, and neuropathic postoperative pain. They successfully respond to treatment with 5% lidocaine-medicated plaster with equal if not better pain control but with fewer side effects versus conventional systemic treatments. Generally, the more localized the pain (ie, the area of an A4 sheet of paper) the better the results of topical treatment. This paper proposes an easy-to-understand algorithm to identify patients with LNP and to guide targeted topical treatments with 5% lidocaine medicated plaster.

Visual pain mapping in endometriosis

PURPOSE

To construct pain maps in order to describe the distribution of pelvic pain in a group of endometriosis patients and endometriosis-free patients, to assess the feasibility of this method.

METHODS

A total of 159 patients with pelvic pain who were scheduled for diagnostic laparoscopy.

RESULTS

A total of 117 patients with and 42 patients without endometriosis were included. The pain distribution between these two patient groups appeared to differ in some peripheral anatomical structures. In the endometriosis patients, the pain was most frequently located in the rectouterine pouch.

CONCLUSIONS

In endometriosis patients, pain mapping to assess preoperative pain sensations relative to the anatomic location of endometriotic lesions is feasible. The pain provoked by vaginal examination is frequently perceived as median relative to the actual anatomic location of the endometriotic lesions. Several anatomic and neurophysiological factors may explain this phenomenon.

Computer-aided surface estimation of pain drawings - intra- and inter-rater reliability

Pain drawings are often utilized in the documentation of pain conditions. The aim here was to investigate intra- and inter-rater reliability of area measurements performed on pain drawings consecutively, using the computer program Quantify One. Forty-eight patients with chronic nonmalignant pain had shaded in their experienced pain on the front and back views of a pain drawing. The templates were scanned and displayed on a 17-inch computer screen. Two independent examiners systematically encircled the shaded-in areas of the pain drawings with help of a computer mouse, twice each on two separate days, respectively. With this method it is possible to encircle each marked area and to obtain immediate details of its size. The total surface area (mm²) was calculated for each pain drawing measurement. Each examiner measured about 2400 areas, and as a whole, the number of areas measured varied only by 3%. The intra-rater reliability was high with intraclass correlation coefficients 0.992 in Examiner A and 0.998 in Examiner B. The intra-individual absolute differences were small within patients within one examiner as well as between the two examiners. The inter-rater reliability was also high. Still, significant differences in the absolute mean areas (13%) were seen between the two examiners in the second to fourth measurement sessions, indicating that one of the examiners measured systematically less. The measurement error was ≤10%, indicating that use of the program would be advantageous both in clinical practice and in research, but if repeated, preferably with the same examiner. Since pain drawings with this method are digitized, high quality data without loss of information is possible to store in electronic medical records for later analysis, both regarding precise location and size of pain area. We conclude that the computer program Quantify One is a reliable method to calculate the areas of pain drawings.

Low back pain at school: unique risk deriving from unsatisfactory grade in maths and school-type recommendation

Psychosocial stress and pain may relate to educational selection. At the end of primary school (International Standard Classification of Education: ISCED level 1) children are recommended for one of three performance-based lower secondary level types of school (ISCED level 2). The study examines the association of educational selection and other risk factors with pain in the upper back (UBP), lower back pain (LBP), peripheral (limb) pain (PP), and abdominal pain (AP). Teacher reports of unsatisfactory grades in mathematics, and official school-type recommendation are included as objective psychosocial risk factors. One hundred and ninety-two schoolchildren, aged between 10 and 13 from 11 classes of 7 schools in Switzerland participated in the cross-sectional study. In logistic regression analysis, predictor variables included age, sex, BMI, participation in sport, physical mobility, weight of satchel, hours of daily TV, video, and computer use, pupils' back pain reported by the mother and father, psychosocial strain, unsatisfactory grade in mathematics, and school-type recommendation. Analysis of pain drawings was highly reliable and revealed high prevalence rates of musculoskeletal pain in the last 4 weeks (UBP 15.3%, LBP 13:8%, PP 33.9%, AP 20.1%). Psychosocial risk factors were uniquely significant predictors of UBP (psychosocial strain), LBP (psychosocial strain, unsatisfactory grade in mathematics, school-type recommendation), and AP (school-type recommendation). In conclusion, selection in terms of educational school system was uniquely associated with LBP in schoolchildren. Stress caused by educational selection should be addressed in primary prevention of musculoskeletal pain in schoolchildren.