Quantified pain drawing in subacute low back pain. Validation in a nonselected outpatient industrial sample

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.

Activity-related pain predicts pain and functional outcomes in people with knee osteoarthritis: A longitudinal study

Knee Osteoarthritis (OA) is a prevalent musculoskeletal condition, commonly resulting in pain and disability. However, pain and disability in this population are poorly related with the degree of structural joint damage. Underlying pain mechanisms, including activity-related pain and sensitization assessed via Quantitative Sensory Testing (QST), may better predict pain and functional outcomes of those with knee OA. Therefore, the aim of this study was to explore whether activity-related pain and sensitization assessed via QST predict future pain, function, fatigue, physical performance and quality of life outcomes in those living in the community with knee OA. Eighty-six participants with knee OA were recruited in Dunedin, New Zealand. Those eligible to participate underwent baseline testing including QST as well as measures of activity-related pain including Movement-evoked Pain (MEP) and Sensitivity to Physical Activity (SPA). Outcome measures exploring pain, function, fatigue and quality of life outcomes were collected at baseline, and two follow-up periods (two and nine weeks). Univariable linear regression models were developed followed by multivariable linear regression models for each prognostic marker adjusting for age, gender, BMI, OA duration, baseline pain intensity and socioeconomic status. Activity-related measures of pain, including MEP and SPA, demonstrated predictive associations with pain and functional outcomes prospectively in those with knee OA. Therefore, those demonstrating activity-related pain are at future risk of greater pain, disability and reduced quality of life. Larger, externally validated longitudinal studies are required which include individuals with more severe knee OA.

Insurance and Employment Status Are Correlated With the Presence of Waddell Signs

OBJECTIVE

The aim of the study was to determine whether employment or insurance status is associated with the presence and number of Waddell signs.

DESIGN

In this cross-sectional study, adult low back pain patients were seen at a tertiary academic center for thoracic or lumbar back pain, due to a degenerative condition. Frequency data were compared with contingency table analysis, including χ2 and logistic regression.

RESULTS

Of 462 patients, 26% had any Waddell signs and 10% had clinically significant Waddell signs. Nonemployed patients had a higher prevalence of Waddell signs than employed and retired patients (P = 0.0004 and P = 0.001, respectively). Subgroups of Medicaid participants as well as patients with secondary gain issues, including worker's compensation and motor vehicle accident, had a higher prevalence of 1+ Waddell signs than patients of other insurances (P < 0.0001 and P = 0.01, respectively). Medicaid participants had a higher prevalence of 3+ Waddell signs than other insurances (P = 0.002).

CONCLUSIONS

The presence of Waddell signs is associated with employment and insurance status. This suggests that social factors may affect patients' perceptions of their thoracic or low back pain. Clinicians aware of these factors can provide individualized care to their patients prone to poor outcomes.

Assessing physical workload among people with musculoskeletal disorders: validity and reliability of the physical workload questionnaire

Background

Demands of physical work are related to musculoskeletal disorders, and hence, important to assess. The Physical Workload Questionnaire (PWQ) is based on 26 items related to physical workload. The PWQ has been translated into Norwegian, but its psychometric properties have not yet been tested. The aim of this study was to assess the validity and reliability of the PWQ among patients with musculoskeletal disorders.

Methods

A cross-sectional study with a test-retest design was conducted to assess construct validity (structural validity and hypothesis testing) and reliability (internal consistency and test-retest reliability) among employed patients with musculoskeletal disorders. Exploratory factor analysis was performed to assess the structural validity and number of items to be included in the Norwegian version of the PWQ. Hypothesis testing was assessed by 14 a priori hypotheses (“known” group, convergent and discriminant validity). Internal consistency was evaluated using Cronbach’s alpha and test-retest reliability by Intraclass Correlation Coefficient (ICC_2.1), Standard Error of Measurement (SEM_agreement) and Smallest Detectable Change (SDC_95%ind).

Results

In total, 115 patients with a mean age (SD) of 46 (9) years were included, of which 48 were included in the reliability analyses. Exploratory factor analysis resulted in two subscales: “Heavy physical work” (15 items, range 0–100) and “Long-lasting postures and repetitive movements” (7 items, range 0–100). No floor or ceiling effects were seen in the subscales. Twelve of the 14 (85%) predefined hypotheses were confirmed. The internal consistency with Cronbach’s alpha was 0.94 and 0.85 on subscales 1 and 2, respectively. Test-retest reliability analyses demonstrated an ICC_2.1 of 0.96 (95% CI 0.88, 0.98) and 0.92 (95% CI 0.81, 0.96), SEM of 6.9 and 10.0 and SDC_95%ind of 19.2 and 27.7 of subscales 1 and 2, respectively.

Conclusions

The Norwegian version of the PWQ demonstrated good validity and reliability and can be used to evaluate physical workload in patients with musculoskeletal disorders.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05222-y.

Significant other interactions in people with chronic low back pain: Subgrouping and multidimensional profiles

Background: Back pain is complex. Social support and significant other interactions influence the pain experience. Purpose: To statistically derive subgroups of people with chronic low back pain based upon their interactions with significant others, and profile subgroups across multidimensional variables. Research Design: Longitudinal cohort study. Study Sample: People with chronic axial low back pain ( n = 262). Data Collection and Analysis: Latent class analysis of significant other interaction data was used to derive subgroups of people with chronic low back pain. Subgroups were profiled across baseline multidimensional variables and one-year follow-up pain intensity, disability and bothersomeness. Results: Three clusters were identified: Cluster 1 (7.6%) characterised by the lowest distracting, punishing and solicitous interactions. Cluster 2 (16.0%) characterised by the highest distracting and solicitous responses and social support. Cluster 3 (76.3%) characterised by the highest punishing and lowest social support. Cluster 1 reported less disability than Clusters 2 and 3. Mindfulness was significantly different across all subgroups with Cluster 1 being most mindful and Cluster 3 least mindful. Depression, anxiety and stress were significantly higher in Cluster 3 than Cluster 1. Pain catastrophising was higher for Cluster 2 than Clusters 1 and 3. Cluster 2 had lower pressure pain threshold than Clusters 1 and 3. Conclusions: These results support the association between significant other interactions and the experience of back pain. Considering significant other interactions in clinical practice may be important for managing some people’s presentation.

Do chronic low back pain subgroups derived from dynamic quantitative sensory testing exhibit differing multidimensional profiles?

OBJECTIVES

The relationship of pain sensitivity with pain and disability in low back pain (LBP) is complicated. It has been suggested increased understanding of dynamic quantitative sensory testing (QST) might be useful in increasing understanding of these relationships. This study aimed to create subgroups based on participant responses to dynamic QST, profile these subgroups based on multidimensional variables (including clinical measures of pain and disability, psychological and lifestyle variables and static QST), and investigate the association of subgroup membership with levels of pain intensity, LBP-related disability and disability risk at 12-month follow up.

METHODS

Participants (n=273) with dominant axial chronic non-specific LBP with duration of pain >3 months were included in this study. At baseline, eligible participants completed a self-report questionnaire to collect demographic, clinical, psychological and lifestyle data prior to dynamic and static QST. Dynamic QST measures were conditioned pain modulation (CPM) and temporal summation (TS). At 12-months follow up, clinical data were collected, including pain intensity and LBP-related disability. Sub-groups were formed by cross-tabulation. Analysis was undertaken to profile dynamic QST subgroup on demographic, clinical, psychological, lifestyle and static QST measures. Associations between dynamic QST subgroups and follow-up clinical variables were examined.

RESULTS

Based on dynamic QST, participants were allocated into four subgroups; normal CPM and normal TS (n=34, 12.5%); normal CPM and facilitated TS (n=6, 2.2%); impaired CPM and normal TS (n=186, 68.1%); impaired CPM and facilitated TS (n=47, 17.2%). At baseline no differences were demonstrated between subgroups across most clinical variables, or any psychological or lifestyle measures. The two subgroups with impaired CPM were more likely to have a higher number of painful body areas. Cold pain sensitivity was heightened in both the subgroups with facilitated TS. Subgroups did not differ across pain intensity, LBP-related disability and disability risk stratification at follow-up.

CONCLUSIONS

The profiles of people with axial LBP did not vary significantly across dynamic QST subgroups, save for those in groups with impaired CPM being more likely to have more widespread symptoms and those with facilitated TS having heightened cold pain sensitivity. Further, subgroup membership was not related to future pain and disability. The role of dynamic QST profiles in LBP remains unclear. Further work is required to understand the role of pain sensitivity in LBP. The utility of dynamic QST subgrouping might not be in determining of future disability. Future research might focus on treatment modifying effects of dynamic QST subgroups.

Colored Pain Drawing as a Clinical Tool in Differentiating Neuropathic Pain from Non-Neuropathic Pain

OBJECTIVES

This is a prospective, blinded, case-control study of patients with chronic pain using body diagrams and colored markers to show the distribution and quality of pain and sensory symptoms (aching, burning, tingling, numbness, and sensitivity to touch) experienced in affected body parts.

METHODS

Two pain physicians, blinded to patients' clinical diagnoses, independently reviewed and classified each colored pain drawing (CPD) for presence of neuropathic pain (NeuP) vs. non-neuropathic pain (NoP). A clinical diagnosis (gold standard) of NeuP was made in 151 of 213 (70.9%) enrolled patients.

RESULTS

CPD assessment at "first glance" by both examiners resulted in correctly categorizing 137 (64.3% by examiner 1) and 156 (73.2% by examiner 2) CPDs. Next, classification of CPDs by both physicians, using predefined criteria of spatial distribution and quality of pain-sensory symptoms, improved concordance to 212 of 213 CPDs (Kappa = 0.99). The diagnostic ability to correctly identify NeuP and NoP by both examiners increased to 171 (80.2%) CPDs, with 80.1% sensitivity and 80.6% specificity (Kappa = 0.56 [95% confidence interval: 0.44-0.68]). The severity scores for pain and sensory symptoms (burning, tingling, numbness, and sensitivity to touch) on the Neuropathic Pain Questionnaire were significantly elevated in NeuP vs. NoP (P < 0.001).

CONCLUSIONS

This study demonstrates good performance characteristics of CPDs in identifying patients with NeuP through the use of a simple and easy-to-apply classification scheme. We suggest use of CPDs as a bedside screening tool and as a method for phenotypic profiling of patients by the quality and distribution of pain and sensory symptoms.

Digital manikins to self-report pain on a smartphone: A systematic review of mobile apps

BACKGROUND

Chronic pain is the leading cause of disability. Improving our understanding of pain occurrence and treatment effectiveness requires robust methods to measure pain at scale. Smartphone-based pain manikins are human-shaped figures to self-report location-specific aspects of pain on people's personal mobile devices.

METHODS

We searched the main app stores to explore the current state of smartphone-based pain manikins and to formulate recommendations to guide their development in the future.

RESULTS

The search yielded 3,938 apps. Twenty-eight incorporated a pain manikin and were included in the analysis. For all apps, it was unclear whether they had been tested and had end-user involvement in the development. Pain intensity and quality could be recorded in 28 and 13 apps, respectively, but this was location specific in only 11 and 4. Most manikins had two or more views (n = 21) and enabled users to shade or select body areas to record pain location (n = 17). Seven apps allowed personalising the manikin appearance. Twelve apps calculated at least one metric to summarise manikin reports quantitatively. Twenty-two apps had an archive of historical manikin reports; only eight offered feedback summarising manikin reports over time.

CONCLUSIONS

Several publically available apps incorporated a manikin for pain reporting, but only few enabled recording of location-specific pain aspects, calculating manikin-derived quantitative scores, or generating summary feedback. For smartphone-based manikins to become adopted more widely, future developments should harness manikins' digital nature and include robust validation studies. Involving end users in the development may increase manikins' acceptability as a tool to self-report pain.

SIGNIFICANCE

This review identified and characterised 28 smartphone apps that included a pain manikin (i.e. pain drawings) as a novel approach to measure pain in large populations. Only few enabled recording of location-specific pain aspects, calculating quantitative scores based on manikin reports, or generating manikin feedback. For smartphone-based manikins to become adopted more widely, future studies should harness the digital nature of manikins, and establish the measurement properties of manikins. Furthermore, we believe that involving end users in the development process will increase acceptability of manikins as a tool for self-reporting pain.

Computerized quantification of pain drawings

Background and aims

Using a computer algorithm to quantify pain drawings could be useful, especially when large numbers of drawings need to be assessed. Whilst informal visual assessment of pain drawings can give clinicians a quick impression of the extent of pain and its location, formal quantification of pain drawings by computer for research purposes is not necessarily trivial. The current study compared seven different approaches to quantification in a large sample of clinical spinal pain drawings.

Methods

A large number (n = 55,720) of pain drawings were extracted from the SpineData database, a clinical registry of spinal pain patients in the Region of Southern Denmark. Drawings were analyzed both as pixel (raster) and vector based images, with different approaches based on the raw pain drawing, simple encircling polygons, convex-hull encircling polygons and discrete anatomical regions. Data were analyzed using principal component analysis, correlation and linear regression, as well as informal visual inspection of outlier pain drawings.

Results

Eighty-one percent of the variance could be explained by the first principal component, which we interpreted as the true score variance, i.e. the variance attributable to differences in pain area between individuals. The second principal component explained 10% of the variance and was loaded differentially by polygon-based methods and non-polygon-based methods. Correlations between the different approaches ranged from 0.66 to 1.00. Some approaches correlated so strongly as to be interchangeable, others tended to bias area estimates significantly. Visual inspection of outlier pain drawing indicated that when the different approaches to quantification yielded different results, characteristic patterns could be identified in the style and patterns of those pain drawings.

Conclusions

The different approaches reflected the same underlying construct (pain area), but could not be relied upon to produce the same area estimates and were affected by the interaction between drawing style and quantification approach. To some extend, the “correct” choice of quantification method is specific to and dictated by the style of each pain drawing. A differentiated approach is required in which the results of quantification and the drawing style are considered in combination. We provide suggestions for such differentiated approaches taking into account the nature of the drawing data (raster vs. vector) and the method of analysis (partly vs completely automated).

Implications

The chosen method of quantifying pain drawings in combination with the drawing style of the individual patient, can impact the resulting area estimate to a significant degree. These issues should be considered before undertaking computerized area estimation of pain drawings.

Spinal Stenosis Patients' Visual and Verbal Description of the Comprehension of Their Surgery

BACKGROUND

Spine surgery patients have difficulty comprehending the patient education aimed at preparing for surgery.

PURPOSE

To assess the effect of a specific preoperative education approach (Knowledge Test Feedback Intervention, KTFI) on patients' verbal and visual understanding of their surgery.

METHODS

In this randomized controlled trial, the intervention group (n = 50) went through the KTFI and routine education, whereas the control group (n = 50) received only routine patient education. Written description of the surgical procedure and drawing of incision were used as outcome measures at baseline, at hospitalization, at discharge, and 3 and 6 months after surgery.

RESULTS

At baseline, half of the participants showed verbal and visual understanding of their surgery. During follow-up, understanding improved significantly with no statistically significant differences between the groups.

CONCLUSION

Spinal stenosis patients' understanding of their surgical procedure is imperfect. Patient educators need to ensure patient learning by evaluating comprehension outcomes.

Chronic low back pain is highly individualised: patterns of classification across three unidimensional subgrouping analyses

BACKGROUND AND AIMS

Chronic low back pain (CLBP) is a complex disorder where central and peripheral nociceptive processes are influenced by factors from multiple dimensions associated with CLBP (e.g. movement, pain sensitivity, psychological). To date, outcomes for treatments matched to unidimensional subgroups (e.g. psychologically-based) have been poor. Therefore, unidimensional subgrouping may not reflect the complexity of CLBP presentations at an individual level. The aim of this study was therefore to explore patterns of classification at an individual level across the three previously-published, data-driven, within-dimension subgrouping studies.

METHODS

Cross-sectional, multidimensional data was collected in 294 people with CLBP. Statistical derivation of subgroups within each of three clinically-important dimensions (pain sensitivity, psychological profile, pain responses following repeated spinal bending) was briefly reviewed. Patterns of classification membership were subsequently tabulated across the three dimensions.

RESULTS

Of 27 possible patterns across these dimensions, 26 were represented across the cohort.

CONCLUSIONS

This result highlights that while unidimensional subgrouping has been thought useful to guide treatment, it is unlikely to capture the full complexity of CLBP. The amount of complexity important for best patient outcomes is currently untested.

IMPLICATIONS

For clinicians this study highlights the high variability of presentations of people with CLBP at the level of the individual. For example, clinician's should not assume that those with high levels of pain sensitivity will also have high psychological distress and have pain summation following repeated spinal bending. A more flexible, multidimensional, clinically-reasoned approach to profile patient complexity may be required to inform individualised, patient-centred care. Such individualised care might improve treatment efficacy. This study also has implications for researchers; highlighting the inadequacy of unidimensional subgrouping processes and methodological difficulties in deriving subgroups across multidimensional data.

The presence of Waddell signs depends on age and gender, not diagnosis

Aims

The aim of this study was to determine if positive Waddell signs were related to patients’ demographics or to perception of their quality of life.

Patients and Methods

This prospective cross-sectional study included 479 adult patients with back pain from a university spine centre. Each completed SF-12 and Oswestry Disability Index (ODI) questionnaires and underwent standard spinal examinations to elicit Waddell signs. The relationship between Waddell signs and age, gender, ODI, Mental Component Score (MCS), and Physical Component Score (PCS) scores was determined.

Results

Of the 479 patients, 128 (27%) had at least one positive Waddell sign. There were significantly more women with two or more Waddell signs than men. The proportion of patients with at least one positive Waddell sign increased with age until 55 years, and then declined rapidly; none had a positive sign over the age of 75 years. Functional outcome scores were significantly worse in those with a single Waddell sign (p < 0.01). With one or more Waddell signs, patients’ PCS and ODI scores indicated a perception of severe disability; with three or more Waddell signs, patients’ MCS scores indicated severe disability. With five Waddell signs, ODI scores indicated that patients perceived themselves as crippled.

Conclusion

Positive Waddell signs, a potential indicator of central sensitization, indicated a likelihood of having functional limitations and an impaired quality of life, particularly in young women. Cite this article: Bone Joint J 2018;100-B:219–25.

Antibiotic treatment In patients with chronic low back pain and Modic changes (the AIM study): study protocol for a randomised controlled trial

Background

A previous randomised controlled trial (RCT) of patients with chronic low back pain (LBP) and vertebral bone marrow (Modic) changes (MCs) on magnetic resonance imaging (MRI), reported that a 3-month, high-dose course of antibiotics had a better effect than placebo at 12 months’ follow-up. The present study examines the effects of antibiotic treatment in chronic LBP patients with MCs at the level of a lumbar disc herniation, similar to the previous study. It also aims to assess the cost-effectiveness of the treatment, refine the MRI assessment of MCs, and further evaluate the impact of the treatment and the pathogenesis of MCs by studying genetic variability and the gene and protein expression of inflammatory biomarkers.

Methods/design

A double-blinded RCT is conducted at six hospitals in Norway, comparing orally administered amoxicillin 750 mg, or placebo three times a day, over a period of 100 days in patients with chronic LBP and type I or II MCs at the level of a MRI-confirmed lumbar disc herniation within the preceding 2 years. The inclusion will be stopped when at least 80 patients are included in each of the two MC type groups. In each MC type group, the study is designed to detect (β = 0.1, α = 0.05) a mean difference of 4 (standard deviation 5) in the Roland Morris Disability Questionnaire score between the two treatment groups (amoxicillin or placebo) at 1-year follow-up. The study includes cost-effectiveness measures. Blood samples are assessed for security measures and for possible inflammatory mediators and biomarkers at different time points. MCs are evaluated on MRI at baseline and after 12 months. A blinded intention-to-treat analysis of treatment effects will be performed in the total sample and in each MC type group.

Discussion

To ensure the appropriate use of antibiotic treatment, its effect in chronic LBP patients with MCs should be re-assessed. This study will investigate the effects and cost-effectiveness of amoxicillin in patients with chronic LBP and MCs at the level of a disc herniation. The study may also help to refine imaging and characterise the biomarkers of MCs.

Trial registration

ClinicalTrials.gov, ID: NCT02323412. Registered on 21 November 2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2306-8) contains supplementary material, which is available to authorized users.

Predictors of low back pain in nursing home workers after implementation of a safe resident handling programme

OBJECTIVES

Healthcare workers have high rates of low back pain (LBP) related to handling patients. A large chain of nursing homes experienced reduced biomechanical load, compensation claims and costs following implementation of a safe resident handling programme (SRHP). The aim of this study was to examine whether LBP similarly declined and whether it was associated with relevant self-reported occupational exposures or personal health factors.

METHODS

Worker surveys were conducted on multiple occasions beginning with the week of first SRHP introduction (baseline). In each survey, the outcome was LBP during the prior 3 months with at least mild severity during the past week. Robust Poisson multivariable regression models were constructed to examine correlates of LBP cross-sectionally at 2 years (F3) and longitudinally at 5-6 years (F5) post-SRHP implementation among workers also in at least one prior survey.

RESULTS

LBP prevalence declined minimally between baseline and F3. The prevalence was 37% at F3 and cumulative incidence to F5 was 22%. LBP prevalence at F3 was positively associated with combined physical exposures, psychological job demands and prior back injury, while frequent lift device usage and 'intense' aerobic exercise frequency were protective. At F5, the multivariable model included frequent lift usage at F3 (relative risk (RR) 0.39 (0.18 to 0.84)) and F5 work-family imbalance (RR=1.82 (1.12 to 2.98)).

CONCLUSIONS

In this observational study, resident lifting device usage predicted reduced LBP in nursing home workers. Other physical and psychosocial demands of nursing home work also contributed, while frequent intense aerobic exercise appeared to reduce LBP risk.

Use of pain drawing as an assessment tool of sciatica for patients with single level lumbar disc herniation

The objectives of this study were to examine the diagnostic accuracy of pain drawing (PD) in determining the level of involvement and to investigate how the quantitative evaluation results of PD using a grid score (GS) correlates with the results of other clinical evaluation measures in diagnosis and assessment of patients with lumber disc herniation (LDH) involving a single nerve root. Thirty-one patients with single level LDH who were diagnosed and conservatively treated by the first author constituted the study population. In order to assess the diagnostic accuracy of PD, the level of involvement as determined by PD was compared to the final diagnosis. In 26 of the 31 patients who could be followed for more than 6 months of conservative treatment, the GS in PD evaluation was compared to the score assessed by the Japanese Orthopaedic Association scoring system for low back pain (JOA score) and the visual analog scale (VAS) both before and after the treatment. The overall diagnostic accuracy of PD for the determination of the affected level averaged 68.8 %, and the accuracy was higher at the L4/5 and L5/S levels than the L2/3 and L3/4 levels. The average values of VAS and GS significantly decreased and the JOA score significantly improved after the treatment. Moreover, a significant correlation was demonstrated between the scores derived from these three evaluation measures. The present study indicated the potential usefulness of PD in clinical assessment during the treatment course.

Reduced pain perception in children and adolescents with ADHD is normalized by methylphenidate

BACKGROUND

The present study examined pain perception in children and adolescents with ADHD and the interaction between pain perception and the administration of methylphenidate (MPH) in order to generate hypotheses for further research that will help to clarify the association between ADHD diagnosis, MPH treatment and pain perception.

METHODS

We included 260 children and adolescents of the "German Health Interview and Examination Survey for Children and Adolescents" (KiGGS) and analyzed parent's assessments of children's pain distribution and pain perception, as well as the influence of MPH administration on pain perception in affected children and adolescents.

RESULTS

Pain perception was associated with ADHD and MPH administration, indicating that children and adolescents suffering from ADHD without MPH treatment were reported to have lower pain perception compared to both, healthy controls (HC) and ADHD patients medicated with MPH.

CONCLUSION

We suggest that reduced pain perception in children and adolescents with ADHD not medicated with MPH may lead to higher risk tolerance by misjudgments of dangerous situations, expanding the importance of MPH administration in affected children and adolescents.

Clinical values of control over pain and pain coping strategies in surgical treatment for patients with lumbar spinal stenosis

BACKGROUND

Control over pain and pain coping strategies are associated with pain intensity as well as psychological status and subjective disability in patients experiencing pain. The present study assessed the clinical values of control over pain and pain coping strategies in surgical treatment for patients with lumbar spinal stenosis using mediation analysis.

METHODS

Sixty-two patients with lumbar spinal stenosis (median age, 70 years; 34 men, 28 women) were evaluated before surgery. The pain intensity and area, psychological status/subjective disability (Japanese Orthopaedic Association Back Pain Evaluation Questionnaire), and control over pain/pain coping strategies (Coping Strategies Questionnaire) were assessed. Mediation analysis, which consisted of serial regression analyses, mainly tested whether (1) control over pain/pain coping strategies were predicted by pain characteristics and (2) control over pain/pain coping strategies predicted psychological status/subjective disability after controlling for pain characteristics.

RESULTS

Control over pain was predicted by pain intensity (regression coefficient, -0.33; p = 0.01); moreover, it predicted walking ability (standardized partial regression coefficient, 0.31; p = 0.01) and social function (0.38; p = 0.00) after controlling for pain intensity. Although increasing activity level, one pain coping strategy, was predicted by pain intensity (regression coefficient, -0.30; p = 0.02), it did not predict walking ability (standardized partial regression coefficient, 0.07; p = 0.53) or social function (0.13; p = 0.33) when considering pain intensity.

CONCLUSIONS

In this cohort, mediation analysis demonstrated that pain intensity did not directly affect perceived walking ability or social function, but did affect control over pain; moreover, control over pain affected walking ability and social function.

CLINICAL RELEVANCE

These findings are useful for a deep understanding of the relationships between pain and subjective disability in preoperative patients with lumbar spinal stenosis. More attention should be given to patients' thoughts about pain such as control over pain.

The pain drawing as an instrument for identifying cervical spine nerve involvement in chronic whiplash-associated disorders

Objective

The aim of the study was to investigate the psychometric properties of a standardized assessment of pain drawing with regard to clinical signs of cervical spine nerve root involvement.

Design

This cross-sectional study included data collected in a randomized controlled study. Patients: Two hundred and sixteen patients with chronic (≥6 months) whiplash-associated disorders, grade 2 or 3, were included in this study.

Methods

The validity, sensitivity, and specificity of a standardized pain drawing assessment for determining nerve root involvement were analyzed, compared to the clinical assessment. In addition, we analyzed the interrater reliability with 50 pain drawings.

Results

Agreement was poor between the standardized pain drawing assessment and the clinical assessment (kappa =0.11, 95% CI: −0.03 to 0.20). Sensitivity was high (93%), but specificity was low (19%). Interrater reliability was good (kappa =0.64, 95% CI: 0.53 to 0.76). Conclusion: The standardized pain drawing assessment of nerve root involvement in chronic whiplash-associated disorders was not in agreement with the clinical assessment. Further research is warranted to optimize the utilization of a pain/discomfort drawing as a supportive instrument for identifying nerve involvement in cervical spinal injuries.

Self-Reported and Tested Function in Health Care Workers with Musculoskeletal Disorders on Full, Partial or Not on Sick Leave

PURPOSE

The aim of this study was to describe self-reported and physically tested function in health care workers with musculoskeletal disorders (MSDs) and to examine how function was associated with work participation.

METHODS

A cross-sectional study was conducted. 250 health care workers attended an evaluation where self-reported and physical function were measured. Differences between groups (full sick leave, partial sick leave, not on sick leave/working) were analyzed for categorical data (Chi square exact test) and continuous variables (Kruskal-Wallis and Mann-Whitney U tests). Logistic regression analysis was performed to examine which factors were associated with being on sick leave.

RESULTS

Participants on full sick leave had statistically significant poorer function compared to those working and the group on partial sick leave. Logistic regression showed that a reduced level of the physical dimension of SF-12 and a high lift test were significantly related to full sick leave (OR 0.86, p < 0.001) (OR 0.79, p = 0.002). The physical dimension of SF-12 was the only variable that was associated to partial sick leave (OR 0.91, p = 0.005).

CONCLUSION

Health care workers on full sick leave due to MSDs have reduced function on self-reported and physically tested function, compared to those working despite MSDs, as well as when compared to those on partial sick leave. More knowledge about work ability in occupational sub-groups is needed.

Evaluative measurement properties of the patient-specific functional scale for primary shoulder complaints in physical therapy practice

STUDY DESIGN

Clinical measurement, longitudinal.

OBJECTIVES

To assess the test-retest reliability, construct validity, and responsiveness of the Patient-Specific Functional Scale (PSFS) in patients with a primary shoulder complaint.

BACKGROUND

Health measurement outcomes have become increasingly important for evaluating treatment. Patient-specific questionnaires are useful tools for determining treatment goals and evaluating treatment in individual patients. These questionnaires have not yet been validated in patients with nonspecific shoulder pain.

METHODS

Patients completed the PSFS, the numeric pain rating scale, and the Shoulder Pain and Disability Index at baseline, and after 1 week and 4 to 6 weeks. Test-retest reliability was determined using intraclass correlation coefficients. To assess convergent validity, change scores of the PSFS were correlated with the numeric pain rating scale and Shoulder Pain and Disability Index change scores. Responsiveness was assessed by calculating the area under the curve, the minimal clinically important change, and minimal detectable change, using the global rating of change as an external criterion.

RESULTS

Fifty patients (37 men; mean age, 47.7 years) participated in the study. Reliability was high (intraclass correlation coefficient = 0.87; 95% confidence interval [CI]: 0.72, 0.94). The correlations between the change scores of the PSFS and those of the Shoulder Pain and Disability Index and numeric pain rating scale were 0.45 (95% CI: 0.17, 0.80) and 0.55 (95% CI: 0.29, 0.73), respectively. The area under the curve for the PSFS was 0.67 (95% CI: 0.51, 0.83). The minimal detectable change and minimal clinically important change were 0.97 and 1.29 points, respectively.

CONCLUSION

These results suggest that the PSFS is a reliable, valid, and responsive instrument that can be used as an evaluative instrument in patients with a primary shoulder complaint.

How fast pain, numbness, and paresthesia resolves after lumbar nerve root decompression: a retrospective study of patient's self-reported computerized pain drawing

STUDY DESIGN

A single-center retrospective study.

OBJECTIVE

To compare the speed of recovery of different sensory symptoms, pain, numbness, and paresthesia, after lumbar nerve root decompression.

SUMMARY OF BACKGROUND DATA

Lumbar radiculopathy is characterized by different sensory symptoms like pain, numbness, and paresthesia, which may resolve at different rates after surgical decompression.

METHODS

Eighty-five cases with predominant lumbar radiculopathy treated surgically were reviewed. Oswestry Disability Index score, 36-Item Short Form Health Survey scores (Physical Component Summary and Mental Component Summary), and pain drawing at preoperative and at 6 weeks, 3 months, 6 months, and 1-year follow-up were reviewed. Recovery rate between different sensory symptoms were compared in all patients, and between the short-term compression (<6 mo) and long-term compression groups.

RESULTS

At baseline, 73 (85.8%) patients had pain, 63 (74.1%) had numbness, and 38 (44.7%) had paresthesia; 28 (32.9%) had all these 3 component of sensory symptoms. Mean pain score improved fastest (55.3% at 6 wk); further resolution until 1 year was slow and not significant compared with each previous visit. Both numbness and paresthesia scores showed a trend of faster recovery during the initial 6-week period (20.5% and 24%, respectively); paresthesia recovery reached a plateau at 3 months postoperatively, but numbness continued a slow recovery until 1-year follow-up. Both Oswestry Disability Index score and Physical Component Summary scores (54.02 ± 1.87 and 26.29 ± 0.93, respectively, at baseline) improved significantly compared with each previous visits at 6 weeks and 3 months postoperatively, but further improvement was insignificant. Mental Component Summary showed a similar trend but smaller improvement. The short-term compression group had faster recovery of pain than the long-term compression group.

CONCLUSION

In lumbar radiculopathy patients after surgical decompression, pain recovers fastest, in the first 6 weeks postoperatively, followed by paresthesia recovery that plateaus at 3 months postoperatively. Numbness recovers at a slower pace but continues until 1 year.

LEVEL OF EVIDENCE

4.

The association between pain diagram area, fear-avoidance beliefs, and pain catastrophising

BACKGROUND

The development of clinical practice guidelines for managing spinal pain have been informed by a biopsychosocial framework which acknowledges that pain arises from a combination of psychosocial and biomechanical factors. There is an extensive body of evidence that has associated various psychosocial factors with an increased risk of experiencing persistent pain. Clinicians require instruments that are brief, easy to administer and score, and capable of validly identifying psychosocial factors. The pain diagram is potentially such an instrument. The aim of our study was to examine the association between pain diagram area and psychosocial factors.

METHODS

183 adults, aged 20-85, with spinal pain were recruited. We administered a demographic checklist; pain diagram; 11-point Numerical Rating Scale assessing pain intensity; Pain Catastrophising Scale (PCS); MOS 36 Item Short Form Health Survey (SF-36); and the Fear Avoidance Beliefs Questionnaire (FABQ). Open source software, GIMP, was used to calculate the total pixilation area on each pain diagram. Linear regression was used to examine the relationship between pain diagram area and the following variables: age; gender; pain intensity; PCS total score; FABQ-Work scale score; FABQ-Activity scale score; and SF-36 Mental Health scale score.

RESULTS

There were no significant associations between pain diagram area and any of the clinical variables.

CONCLUSION

Our findings showed that that pain diagram area was not a valid measure to identify psychosocial factors. Several limitations constrained our results and further studies are warranted to establish if pain diagram area can be used assess psychosocial factors.

The use of weekly text messaging over 6 months was a feasible method for monitoring the clinical course of low back pain in patients seeking chiropractic care

OBJECTIVE

This study critically evaluates a new method of collecting frequent data using mobile phones and text messages. Fluctuating conditions such as low back pain (LBP) need frequent monitoring to describe the clinical course in detail and to account for individual and subgroup variations.

STUDY DESIGN AND SETTING

In this multicentre prospective observational study, 262 subjects with nonspecific LBP were followed with weekly text messages for 6 months, with the question "How many days this previous week has your low back pain been bothersome?" The text replies were instantly recorded in a data file to be merged with baseline and follow up data (age, gender, pain intensity, duration, and self- rated health) collected through ordinary questionnaires. The response rate, user-friendliness, and compliance of this method were evaluated.

RESULTS

The mean response rate for the text messages throughout the study was 82.5% and was unaffected by season. The method was found to be user friendly. Dropout was not affected by age and gender, but compliance was possibly somewhat affected by outcome.

CONCLUSION

Weekly text messages are a useful method of data collection to examine the clinical course of LBP in the primary care sector.

Clustering patients on the basis of their individual course of low back pain over a six month period

Background

Several researchers have searched for subgroups in the heterogeneous population of patients with non-specific low back pain (LBP). To date, subgroups have been identified based on psychological profiles and the variation of pain.

Methods

This multicentre prospective observational study explored the 6- month clinical course with measurements of bothersomeness that were collected from weekly text messages that were sent by 176 patients with LBP. A hierarchical cluster analysis, Ward's method, was used to cluster patients according to the development of their pain.

Results

Four clusters with distinctly different clinical courses were described and further validated against clinical baseline variables and outcomes. Cluster 1, a "stable" cluster, where the course was relatively unchanged over time, contained young patients with good self- rated health. Cluster 2, a group of "fast improvers" who were very bothered initially but rapidly improved, consisted of patients who rated their health as relatively poor but experienced the fewest number of days with bothersome pain of all the clusters. Cluster 3 was the "typical patient" group, with medium bothersomeness at baseline and an average improvement over the first 4-5 weeks. Finally, cluster 4 contained the "slow improvers", a group of patients who improved over 12 weeks. This group contained older individuals who had more LBP the previous year and who also experienced most days with bothersome pain of all the clusters.

Conclusions

It is possible to define clinically meaningful clusters of patients based on their individual course of LBP over time. Future research should aim to reproduce these clusters in different populations, add further clinical variables to distinguish the clusters and test different treatment strategies for them.

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.

Are prognostic indicators for poor outcome different for acute and chronic low back pain consulters in primary care?

Few studies have investigated whether prognostic indicators, which contribute to the transition from acute to chronic low back pain (LBP), are also those which contribute to continuing persistence of chronic LBP. We compared the contribution of physical, psychological and social indicators to predicting disability after one year between consulters with LBP of less than 3 months duration and more than 3 months duration. Data from two large prospective cohort studies of consecutive patients consulting with LBP in general practices were merged, providing complete data for 258 cases with acute/subacute LBP and 668 cases with chronic LBP at 12 months follow-up. There were significant differences between the two LBP groups in baseline characteristics and clinical course of disability, assessed by Roland Morris Disability Questionnaire, during the year of follow-up. Adjusted associations between potential prognostic indicators and disability at 12months were carried out in the two LBP subgroups. The final multivariable regression models showed that being non-employed, having widespread pain, a high level of Chronic Pain Grade, and catastrophising were the strongest prognostic indicators for disability at 12 months in both LBP groups. Fear of pain was significantly associated with disability in chronic LBP. Importantly, beyond baseline disability, the effect size of the other prognostic indicators for poor outcome was rather low. These findings must continue to challenge researchers to identify useful early predictors of outcome in persons with disabling back pain, as screening and targeted treatment approaches are dependent upon prognostic indicators with clinical significance.

Are MRI high-signal changes of alar and transverse ligaments in acute whiplash injury related to outcome?

Background

Upper neck ligament high-signal changes on magnetic resonance imaging (MRI) have been found in patients with whiplash-associated disorders (WAD) but also in non-injured controls. The clinical relevance of such changes is controversial. Their prognostic role has never been evaluated. The purpose of this study was to examine if alar and transverse ligament high-signal changes on MRI immediately following the car accident are related to outcome after 12 months for patients with acute WAD grades 1-2.

Methods

Within 13 days after a car accident, 114 consecutive acute WAD1-2 patients without prior neck injury or prior neck problems underwent upper neck high-resolution proton-weighted MRI. High-signal changes of the alar and transverse ligaments were graded 0-3. A questionnaire including the impact of event scale for measuring posttraumatic stress response and questions on patients' expectations of recovery provided clinical data at injury. At 12 months follow-up, 111 (97.4%) patients completed the Neck Disability Index (NDI) and an 11-point numeric rating scale (NRS-11) on last week neck pain intensity. Factors potentially related to these outcomes were assessed using multiple logistic regression analyses.

Results

Among the 111 responders (median age 29.8 years; 63 women), 38 (34.2%) had grades 2-3 alar ligament changes and 25 (22.5%) had grades 2-3 transverse ligament changes at injury. At 12 months follow-up, 49 (44.1%) reported disability (NDI > 8) and 23 (20.7%) neck pain (NRS-11 > 4). Grades 2-3 ligament changes in the acute phase were not related to disability or neck pain at 12 months. More severe posttraumatic stress response increased the odds for disability (odds ratio 1.46 per 10 points on the impact of event scale, p = 0.007) and so did low expectations of recovery (odds ratio 4.66, p = 0.005).

Conclusions

High-signal changes of the alar and transverse ligaments close after injury did not affect outcome for acute WAD1-2 patients without previous neck problems. High-resolution upper neck MRI has limited value for the initial examination and follow-up of such patients.

The cartography of pain: the evolving contribution of pain maps

Pain maps are nowadays widely used in clinical practice. This article aims to critically review the fundamental principles that underlie the mapping of pain, to analyse the evolving iconography of pain maps and their sometimes straightforward and sometimes contentious nature when used in the clinic, and to draw attention to some more recent developments in mapping pain. It is concluded that these maps are intriguing and evolving cartographic tools which can be used for depicting not only the spatial features but also the interpretative or perceptual components and accompaniments of pain.

Pain patterns and descriptions in patients with radicular pain: does the pain necessarily follow a specific dermatome?

Background

It is commonly stated that nerve root pain should be expected to follow a specific dermatome and that this information is useful to make the diagnosis of radiculopathy. There is little evidence in the literature that confirms or denies this statement. The purpose of this study is to describe and discuss the diagnostic utility of the distribution of pain in patients with cervical and lumbar radicular pain.

Methods

Pain drawings and descriptions were assessed in consecutive patients diagnosed with cervical or lumbar nerve root pain. These findings were compared with accepted dermatome maps to determine whether they tended to follow along the involved nerve root's dermatome.

Results

Two hundred twenty-six nerve roots in 169 patients were assessed. Overall, pain related to cervical nerve roots was non-dermatomal in over two-thirds (69.7%) of cases. In the lumbar spine, the pain was non-dermatomal in just under two-thirds (64.1%) of cases. The majority of nerve root levels involved non-dermatomal pain patterns except C4 (60.0% dermatomal) and S1 (64.9% dermatomal). The sensitivity (SE) and specificity (SP) for dermatomal pattern of pain are low for all nerve root levels with the exception of the C4 level (Se 0.60, Sp 0.72) and S1 level (Se 0.65, Sp 0.80), although in the case of the C4 level, the number of subjects was small (n = 5).

Conclusion

In most cases nerve root pain should not be expected to follow along a specific dermatome, and a dermatomal distribution of pain is not a useful historical factor in the diagnosis of radicular pain. The possible exception to this is the S1 nerve root, in which the pain does commonly follow the S1 dermatome.

The effect of two exercise regimes; motor control versus endurance/strength training for patients with whiplash-associated disorders: a randomized controlled pilot study

Objective: To compare the effect of exercise regimes with focus on either motor control training or endurance/strength training for patients with whiplash-associated disorders in subacute phase.

Design: Randomized controlled trial.

Setting: An outpatient spine clinic in Norway.

Participants: Twenty-five subjects with a whiplash-associated disorder still having symptoms or disability six weeks after injury.

Interventions: The participants received 6—10 sessions of physiotherapy for six weeks with focus on either motor control or endurance and strength of neck muscles.

Measurements: The primary outcome measure was the Neck Disability Index. Secondary outcome measures were pain intensity, neck functioning and sick leave.

Results: No statistical significant differences concerning primary and secondary outcome measures were demonstrated between the groups. Approximately half of the participants in both groups obtained a clinically important change (improvement) on perceived disability assessed by Neck Disability Index at six weeks and one-year follow-up. The changes within both groups were statistically significant at six weeks, but not at one-year follow-up. For most pain-related variables clinical significant improvement was demonstrated in both groups at six weeks, but for fewer participants at one year. There was also statistical significant improvement within groups in some of the physical performance tests at one-year follow-up.

Conclusion: The changes associated with motor control training and endurance/ strength training of neck muscles were similar for reduced disability, pain and for improving physical performance. With a low number of participants and no control group, however, we cannot be sure whether the improvements are due to interventions or other reasons.

A prospective, masked 18-month minimum follow-up on neurophysiologic changes in persons with spinal stenosis, low back pain, and no symptoms

OBJECTIVES

To describe neurophysiologic changes over time in persons with and without spinal complaints and to assess whether paraspinal denervation predicts change in stenosis on magnetic resonance imaging (MRI) and clinical course.

DESIGN

Prospective, controlled, masked trial.

SETTING

University spine program.

PARTICIPANTS

Persons aged 55 to 80 years, screened for polyneuropathy and determined on clinical examination to have spinal stenosis, mechanical low back pain, or no spinal symptoms.

INTERVENTIONS

A comprehensive codified history was obtained and subjects underwent physical examination, ambulation testing, masked electrodiagnostic testing including paraspinal mapping, and MRI, repeated at greater than 18 months. This study presents detailed technical information and additional analyses not reported previously.

MAIN OUTCOME MEASUREMENTS

Change in electrodiagnostic findings. Among persons with clinical stenosis, relationship of change in paraspinal mapping scores to MRI findings and clinical changes.

RESULTS

Of 149 initial subjects, 83 (79.3% of eligible subjects) repeated testing at 20 (+/-2 SDs) months. No significant change in limb muscle spontaneous activity or motor unit pathology was noted in any group. In 23 persons with initial diagnosis of stenosis, paraspinal mapping electromyography related to change in diagnosis over time (analysis of variance F = 3.77, P = .037), but not to most initial magnetic resonance imaging measurements or to change in spinal canal diameter.

CONCLUSIONS

Clinical spinal stenosis is neurophysiologically stable in most persons. Paraspinal electromyographic changes reflect large changes in clinical course, but neither neurophysiologic nor clinical changes relate to change in spinal geometry over 20 months.

Parents with chronic pain: are children equally affected by fathers as mothers in pain? A pilot study

This study compared the psychological and physical functioning of 12 children in each of three groups: mothers with chronic pain, fathers with chronic pain and a control, pain-free parents. Parents completed a number of questionnaires including the RAND-36 Health Status Inventory, a child health scale and the Child Behavior Checklist. Children completed the Revised Child Manifest Anxiety Scale and a scale measuring pain and sickness behaviour. Children of mothers with chronic pain reported the most physical and psychological problems, followed by children of fathers with chronic pain and children from the control group. Pain reports between children and parents with chronic pain were significantly correlated, suggesting support for a familial pain model. Social learning may explain the concordance between parent and child health in families experiencing parental chronic pain.

Sex differences in pain drawing area for individuals with chronic musculoskeletal pain

STUDY DESIGN

Cross-sectional.

OBJECTIVES

To (1) determine the association between pain severity and pain drawing area for men and women; (2) determine if sex differences exist in pain severity or pain drawing area; (3) determine the relative influence of pain severity, anatomical location of pain, personality, and psychological coping factors on pain drawing area for men and women.

BACKGROUND

Pain drawings have been postulated to assist in clinical decision making regarding classification and treatment of musculoskeletal pain. Prior studies have been ambiguous on this topic, possibly because they have not considered if sex differences exist for pain drawing area.

METHODS AND MEASURES

One hundred twenty-six subjects referred to a multidisciplinary chronic pain clinic with chronic musculoskeletal pain were included in this study. Subjects completed a pain drawing, the Multidimensional Pain Inventory (MPI), the Coping Strategies Questionnaire (CSQ), and the Minnesota Multiphasic Personality Inventory (MMPI-2). Pearson correlations investigated the associations of pain severity and pain drawing area, independent t tests investigated sex differences in pain severity and pain drawing area, and multiple regression investigated factors that influenced pain drawing area.

RESULTS

P a in severity w as positively correlated with pain drawing area for men (r = 0.38, P = .003) and women (r = 0.23, P = .052), accounting for approximately 14% and 5% of the total variance, respectively. There was no significant sex difference in pain severity ratings, but women reported a significantly larger area of symptoms on the pain drawings (effect size, 0.61; P = .002). The sex difference in pain drawing area was consistent across different anatomical locations of pain. In women, the final regression model accounted for 39% (P < .001) of the variance in pain drawing area, with anatomical location of pain (beta = .42, P < .001) and hypochondriasis (beta = .31, P = .005) as the only unique predictors in the final model. In men, the regression model accounted for 27% (P = .003) of the variance in pain drawing area, with pain severity (beta = .32, P = .021) and a coping style of ignoring pain (beta = -.32, P = .018) as the only unique predictors in the final model.

CONCLUSIONS

Women had larger pain drawing area and this area was significantly associated with anatomical location of pain and hypochondriasis. Men had smaller pain drawing area and this area was associated with pain severity and a coping style of ignoring pain. These findings suggest that clinicians interpreting pain diagram area should consider the sex of the individual.

Electromyographic and magnetic resonance imaging to predict lumbar stenosis, low-back pain, and no back symptoms

BACKGROUND

Magnetic resonance imaging is commonly used to diagnose lumbar spinal stenosis. Some persons without symptoms have a small lumbar spinal canal. Electrodiagnosis has been used to diagnose spinal stenosis for over sixty years, but we are aware of no masked, controlled trials of the use of electrodiagnosis for that purpose. This study was performed to evaluate the relationships of magnetic resonance imaging measures and electrodiagnostic data with the clinical syndrome of spinal stenosis.

METHODS

One hundred and fifty persons between the ages of fifty-five and eighty years old, including asymptomatic volunteers and persons referred for lumbar magnetic resonance imaging, underwent clinical examination, electrodiagnosis, and magnetic resonance imaging. Subjects were excluded if they had neuromuscular disease, sacral cancer, or inadequate test results, which left 126 subjects for the final analysis. The final cohort was divided into three groups--no back pain, mechanical back pain, and clinical spinal stenosis--on the basis of the impression of the examining physician, for whom the results of the magnetic resonance imaging and electrodiagnostic testing were masked. A spine surgeon also reviewed both the imaging and clinical examination data.

RESULTS

The examining physician's diagnosis of clinical spinal stenosis was significantly related to the neurological findings on examination (p < 0.05) and to the spine surgeon's diagnosis (p < 0.001). The diagnosis of clinical spinal stenosis was also significantly related to the presence of fibrillations on electrodiagnostic testing (p < or = 0.003), the minimum anteroposterior diameter of the spinal canal on the magnetic resonance images (p = 0.016), and the average of the two smallest spinal canal diameters (p = 0.008) on the images. Measurements on magnetic resonance imaging did not differentiate subjects with clinical spinal stenosis from controls better than chance, whereas paraspinal mapping electrodiagnosis scores did.

CONCLUSIONS

This prospective, controlled, masked study of electrodiagnosis and magnetic resonance imaging for older subjects showed that imaging does not differentiate symptomatic from asymptomatic persons, whereas electrodiagnosis does. We believe that radiographic findings alone are insufficient to justify treatment for spinal stenosis.

Functional restoration for a chronic lumbar disk extrusion with associated radiculopathy

BACKGROUND AND PURPOSE

The effectiveness of functional restoration (FR) for patients with lumbar disk herniation with associated radiculopathy (LDHR) is unclear. This case report describes how an FR program was used to rehabilitate a patient with such an injury.

CASE DESCRIPTION

The patient was a 26-year-old female child care worker with a 12-month history of back pain and a 4-month history of unremitting left leg symptoms. She had clinical and radiological evidence of an L5-S1 disk extrusion with associated left S1 radiculopathy. Interventions. The patient completed a 9-week FR program supervised by a physical therapist. Exercises then were continued more independently for a 2-year period at a public gymnasium.

OUTCOMES

Following 9 weeks of supervised FR, the patient demonstrated marked improvement in symptoms and functional ability, and resolution of neurological signs. Fourteen months after commencing FR, a follow-up magnetic resonance imaging scan demonstrated resolution of the L5-S1 disk extrusion and relief of S1 nerve root compression. Functional improvements continued and were maintained 2 years following the start of intervention.

DISCUSSION

A patient with chronic LDHR who underwent FR made significant improvements. Research is needed to determine the efficacy of an FR approach for treating such patients.

Predictors of pain and function in persons with spinal stenosis, low back pain, and no back pain

STUDY DESIGN

Longitudinal masked, double-controlled cohort study.

OBJECTIVES

To determine prognosis and predictors of function and pain in persons with spinal stenosis.

SUMMARY OF BACKGROUND DATA

The clinical syndrome of spinal stenosis is common and disabling, but not clearly related to anatomic measures. Prognosis not well studied.

METHODS

Persons 55 to 80 years of age with and without stenosis on preliminary review of magnetic resonance imaging (MRI), and asymptomatic volunteers underwent screening, questionnaires, physical examination, ambulation testing, masked electromyogram (EMG), and masked MRI scans; these were repeated at >18 months.

RESULTS

Twenty-three asymptomatic, 28 back pain, and 32 clinically diagnosed stenosis subjects underwent follow-up. Although initial and follow-up diagnosis tended to agree (kappa = 0.394, P < 001), there were substantial shifts between the three groups. Among persons with clinically diagnosed stenosis, every measure trended for improvement, including significant changes in pain, ambulation, and EMG. Ambulation velocity and Pain Disability Index at follow-up were predicted by initial disability measures. Pain was predicted by initial sleep difficulty but not initial pain. EMG and MRI did not predict function or pain.

CONCLUSION

Clinically recognized spinal stenosis is fluctuating and largely improving, and in continuum with back pain and no symptoms. Since anatomic and neurologic deficits do not predict future function, they should not be weighed heavily in surgical risk-benefit discussions.

Pain drawing scoring is not improved by inclusion of patient-reported pain sensation

STUDY DESIGN

This is a retrospective study of 250 patients who describe low back pain with pain drawings. A computer application using artificial neural networks was designed to analyze pain drawings and evaluate the contribution of pain sensation to drawing classification.

OBJECTIVE

The primary goal of this study was to assess the contribution of patient recorded pain sensation marks in classifying pain drawings into one of five broadly defined categories. The hypothesis was that including pain sensation would improve classification.

SUMMARY OF BACKGROUND DATA

With no perfect diagnostic test for patients with low back pain, many approaches have been proposed and are used. One common diagnostic tool is the pain drawing. Several quantitative methods have been proposed to score the drawings. Some methods use pain sensation in the scoring; however, the contribution of pain sensation has not been defined.

METHODS

A custom computer application classified the pain drawing. Data consisted of 250 pain drawings from patients with low back pain.

RESULTS

Patient recorded pain sensation is not necessary in computer-based scoring of pain drawings.

CONCLUSION

Patient-reported pain sensation does not improve classification when quantitatively scoring pain drawings.

Prediction of sickness absence in patients with chronic low back pain: a systematic review

OBJECTIVES

To provide evidence of predictors for sickness absence in patients with non-specific chronic low back pain (CLBP), distinguishing predictors aimed at the decision to report sick (absence threshold) and decision to return to work (return to work threshold).

METHODS

Medical and psychological databases were searched, as well as citations from relevant reviews. In- and exclusion criteria were applied. Two reviewers assessed the methodological quality of the papers independently.

RESULTS

Many different predictors were studied, and few factors were studied more than once. Consistent evidence was found for own expectations of recovery only as predictor for the decision to return to work. Patients with higher expectations had less sickness absence at the moment of follow-up measurement. As expected, different predictors were found aiming at the absence threshold or the return to work threshold. Furthermore, predictors varied also with the measurement instruments used, timing of follow-up measurements, and definition of outcomes. Until now, too few studies are available to overcome several potential sources of heterogeneity.

CONCLUSIONS

No core set of predictors exists for sickness absence in general. The characteristics of the study including the decision to report sick or to return to work determined the influence of several predictors on sickness absence in patients with CLBP. Further research and use of a core set of measurements and uniform definitions are needed to predict sickness absence and return to work in patients with CLBP.