Jan Hartvigsen

A Consensus Approach Toward the Standardization of Back Pain Definitions for Use in Prevalence Studies

Study Design. A modified Delphi study conducted with 28 experts in back pain research from 12 countries. Objective. To identify standardized definitions of low back pain that could be consistently used by investigators in prevalence studies to provide comparable data. Summary of Background Data. Differences in the definition of back pain prevalence in population studies lead to heterogeneity in study findings, and limitations or impossibilities in comparing or summarizing prevalence figures from different studies. Methods. Back pain definitions were identified from 51 articles reporting population-based prevalence studies, and dissected into 77 items documenting 7 elements. These items were submitted to a panel of experts for rating and reduction, in 3 rounds (participation: 76%). Preliminary results were presented and discussed during the Amsterdam Forum VIII for Primary Care Research on Low Back Pain, compared with scientific evidence and confirmed and fine-tuned by the panel in a fourth round and the preparation of the current article. Results. Two definitions were agreed on a minimal definition (with 1 question covering site of low back pain, symptoms observed, and time frame of the measure, and a second question on severity of low back pain) and an optimal definition that is made from the minimal definition and add-ons (covering frequency and duration of symptoms, an additional measure of severity, sciatica, and exclusions) that can be adapted to different needs. Conclusion. These definitions provide standards that may improve future comparisons of low back pain prevalence figures by person, place and time characteristics, and offer opportunities for statistical summaries.

Responsiveness and minimal clinically important difference for pain and disability instruments in low back pain patients

BackgroundThe choice of an evaluative instrument has been hampered by the lack of head-to-head comparisons of responsiveness and the minimal clinically important difference (MCID) in subpopulations of low back pain (LBP). The objective of this study was to concurrently compare responsiveness and MCID for commonly used pain scales and functional instruments in four subpopulations of LBP patients.MethodsThe Danish versions of the Oswestry Disability Index (ODI), the 23-item Roland Morris Disability Questionnaire (RMQ), the physical function and bodily pain subscales of the SF36, the Low Back Pain Rating Scale (LBPRS) and a numerical rating scale for pain (0–10) were completed by 191 patients from the primary and secondary sectors of the Danish health care system. Clinical change was estimated using a 7-point transition question and a numeric rating scale for importance. Responsiveness was operationalised using standardardised response mean (SRM), area under the receiver operating characteristic curve (ROC), and cut-point analysis. Subpopulation analyses were carried out on primary and secondary sector patients with LBP only or leg pain +/- LBP.ResultsRMQ was the most responsive instrument in primary and secondary sector patients with LBP only (SRM = 0.5–1.4; ROC = 0.75–0.94) whereas ODI and RMQ showed almost similar responsiveness in primary and secondary sector patients with leg pain (ODI: SRM = 0.4–0.9; ROC = 0.76–0.89; RMQ: SRM = 0.3–0.9; ROC = 0.72–0.88). In improved patients, the RMQ was more responsive in primary and secondary sector patients and LBP only patients (SRM = 1.3–1.7) while the RMQ and ODI were equally responsive in leg pain patients (SRM = 1.3 and 1.2 respectively). All pain measures demonstrated almost equal responsiveness. The MCID increased with increasing baseline score in primary sector and LBP only patients but was only marginally affected by patient entry point and pain location. The MCID of the percentage change score remained constant for the ODI (51%) and RMQ (38%) specifically and differed in the subpopulations.ConclusionRMQ is suitable for measuring change in LBP only patients and both ODI and RMQ are suitable for leg pain patients irrespectively of patient entry point. The MCID is baseline score dependent but only in certain subpopulations. Relative change measured using the ODI and RMQ was not affected by baseline score when patients quantified an important improvement.

Is sitting-while-at-work associated with low back pain? A systematic, critical literature review.

OBJECTIVES To present a critical review and evaluate recent reports investigating sitting-while-at-work as a risk factor for low back pain (LBP). METHODS The Medline, Embase and OSH-ROM databases were searched for articles dealing with sitting at work in relation to low back pain for the years 1985-97. The studies were divided into those dealing with sitting-while-working and those dealing with sedentary occupations. Each article was systematically abstracted for core items. The quality of each article was determined based on the representativeness of the study sample, the definition of LBP, and the statistical analysis. RESULTS Thirty-five reports were identified, 14 dealing with sitting-while-working and 21 with sedentary occupations. Eight studies were found to have a representative sample, a clear definition of LBP and a clear statistical analysis. Regardless of quality, all but one of the studies failed to find a positive association between sitting-while-working and LBP. High quality studies found a marginally negative association for sitting compared to diverse workplace exposures, e.g. standing, driving, lifting bending, and compared to diverse occupations. One low quality study associated sitting in a poor posture with LBP. CONCLUSIONS The extensive recent epidemiological literature does not support the popular opinion that sitting-while-at-work is associated with LBP.

Pain in the lumbar, thoracic or cervical regions: do age and gender matter? A population-based study of 34,902 Danish twins 20–71 years of age

BackgroundIt is unclear to what extent spinal pain varies between genders and in relation to age. It was the purpose of this study to describe the self-reported prevalence of 1) pain ever and pain in the past year in each of the three spinal regions, 2) the duration of such pain over the past year, 3) pain radiating from these areas, and 4) pain in one, two or three areas. In addition, 5) to investigate if spinal pain reporting is affected by gender and 6) to see if it increases gradually with increasing age.MethodA cross-sectional survey was conducted in 2002 on 34,902 twin individuals, aged 20 to 71 years, representative of the general Danish population. Identical questions on pain were asked for the lumbar, thoracic and cervical regions.ResultsLow back pain was most common, followed by neck pain with thoracic pain being least common. Pain for at least 30 days in the past year was reported by 12%, 10%, and 4%, respectively. The one-yr prevalence estimates of radiating pain were 22% (leg), 16% (arm), and 5% (chest). Pain in one area only last year was reported by 20%, followed by two (13%) and three areas (8%).Women were always more likely to report pain and they were also more likely to have had pain for longer periods. Lumbar and cervical pain peaked somewhat around the middle years but the curves were flatter for thoracic pain. Similar patterns were noted for radiating pain. Older people did not have pain in a larger number of areas but their pain lasted longer.ConclusionPain reported for and from the lumbar and cervical spines was found to be relatively common whereas pain in the thoracic spine and pain radiating into the chest was much less common. Women were, generally, more likely to report pain than men. The prevalence estimates changed surprisingly little over age and were certainly not more common in the oldest groups, although the pain was reported as more long-lasting in the older group.

A Systematic, Critical Review of Manual Palpation for Identifying Myofascial Trigger Points: Evidence and Clinical Significance

OBJECTIVE To determine the reproducibility of manual palpation in identifying trigger points based on a systematic review of available literature. DATA SOURCES Medline (1965-2007), CINHAL (1982-2007), ISI Web of Science (1945-2007), and MANTIS (1966-2007) databases and reference lists of articles. STUDY SELECTION Reproducibility studies relating to identification and diagnosis of trigger points through palpation. Acceptable studies were required to specifically consider either inter- or intrarater reliability of trigger point identification through manual palpation and include kappa statistics as part of their statistical assessment. DATA EXTRACTION Three independent reviewers considered the studies for inclusion and rated their methodologic quality based on the Standards for Reporting of Diagnostic Accuracy guidelines for the reporting of diagnostic studies. DATA SYNTHESIS Eleven studies were initially included; however, 5 were subsequently excluded based on the inclusion and exclusion criteria. Only 2 studies were judged to be of high quality, and the level of evidence criteria suggested that, at best, moderate evidence could be found from which to make pronouncements on the literature. Only local tenderness of the trapezius (kappa range, .15-.62) and pain referral of the gluteus medius (kappa range, .298-.487) and quadratus lumborum (kappa range, .36-.501) were found to be reproducible. CONCLUSIONS The methodologic quality of the majority of studies for the purpose of establishing trigger point reproducibility is generally poor. More high-quality studies are needed to comment on this procedure. Clinicians and scientists are urged to move toward simpler, global assessments of patient status.

Systematic review of the prognosis after mild traumatic brain injury in adults: cognitive, psychiatric, and mortality outcomes: results of the International Collaboration on Mild Traumatic Brain Injury Prognosis.

OBJECTIVE To synthesize the best available evidence on objective outcomes after adult mild traumatic brain injury (MTBI). DATA SOURCES MEDLINE and other databases were searched (2001-2012) for studies related to MTBI. Inclusion criteria included published, peer-reviewed articles in English and other languages. References were also identified from the bibliographies of eligible articles. STUDY SELECTION Randomized controlled trials and cohort and case-control studies were selected according to predefined criteria. Studies had to have a minimum of 30 MTBI cases and assess objective outcomes in adults. DATA EXTRACTION Eligible studies were critically appraised using a modification of the Scottish Intercollegiate Guidelines Network (SIGN) criteria. Two reviewers independently reviewed each study and extracted data from accepted articles into evidence tables. DATA SYNTHESIS Evidence was synthesized qualitatively according to modified SIGN criteria, and studies were categorized as exploratory or confirmatory based on the strength of their design and evidence. After 77,914 records were screened, 299 were found to be relevant and critically reviewed, and 101 were deemed scientifically admissible. Of these, 21 studies that were related to the objective outcomes form the basis of this review. Most evidence indicates the presence of cognitive deficits in the first 2 weeks post-MTBI, and some evidence suggests that complete recovery may take 6 months or a year. A small number of studies indicate that MTBI increases the risk of psychiatric illnesses and suicide. CONCLUSIONS Early cognitive deficits are common, and complete recovery may be prolonged. Conclusions about mortality post-MTBI are limited. This review has implications for expected recovery after MTBI and MTBI-related health sequelae. Well-designed confirmatory studies are needed to understand the medium- to long-term consequences of MTBI and to further evaluate the effect of prior MTBI and injury severity on recovery.

Systematic Review of Self-Reported Prognosis in Adults After Mild Traumatic Brain Injury: Results of the International Collaboration on Mild Traumatic Brain Injury Prognosis

OBJECTIVE To update the mild traumatic brain injury (MTBI) prognosis review published by the World Health Organization Task Force in 2004. DATA SOURCES MEDLINE, PsycINFO, Embase, CINAHL, and SPORTDiscus were searched from 2001 to 2012. We included published, peer-reviewed studies with more than 30 adult cases. STUDY SELECTION Controlled trials and cohort and case-control studies were selected according to predefined criteria. Studies had to assess subjective, self-reported outcomes. After 77,914 titles and abstracts were screened, 299 articles were eligible and reviewed for scientific quality. This includes 3 original International Collaboration on MTBI Prognosis (ICoMP) research studies. DATA EXTRACTION Eligible studies were critically appraised using the Scottish Intercollegiate Guidelines Network criteria. Two reviewers independently reviewed each study and tabled data from accepted articles. A third reviewer was consulted for disagreements. DATA SYNTHESIS Evidence from accepted studies was synthesized qualitatively into key findings, and prognostic information was prioritized according to design as exploratory or confirmatory. Of 299 reviewed studies, 101 (34%) were accepted and form our evidence base of prognostic studies. Of these, 23 addressed self-reported outcomes in adults, including 2 of the 3 original ICoMP research studies. These studies show that common postconcussion symptoms are not specific to MTBI/concussion and occur after other injuries as well. Poor recovery after MTBI is associated with poorer premorbid mental and physical health status and with more injury-related stress. Most recover over 1 year, but persistent symptoms are more likely in those with more acute symptoms and more emotional stress. CONCLUSIONS Common subjective symptoms after MTBI are not necessarily caused by brain injury per se, but they can be persistent in some patients. Those with more initial complaints and psychological distress recover slower. We need more high-quality research on these issues.

Review Article: Is sitting-while-at-work associated with low back pain? A systematic, critical literature review

Objectives: To present a critical review and evaluate recent reports investigating sitting-while-at-work as a risk factor for low back pain (LBP). Methods: The Medline, Embase and OSH-ROM databases were searched for articles dealing with sitting at work in relation to low back pain for the years 1985-97. The studies were divided into those dealing with sitting-while-working and those dealing with sedentary occupations. Each article was systematically abstracted for core items. The quality of each article was determined based on the representativeness of the study sample, the definition of LBP, and the statistical analysis. Results: Thirty-five reports were identified, 14 dealing with sitting-while-working and 21 with sedentary occupations. Eight studies were found to have a representative sample, a clear definition of LBP and a clear statistical analysis. Regardless of quality, all but one of the studies failed to find a positive association between sitting-while-working and LBP. High quality studies found a marginally negative association for sitting compared to diverse workplace exposures, e.g. standing, driving, lifting bending, and compared to diverse occupations. One low quality study associated sitting in a poor posture with LBP. Conclusions: The extensive recent epidemiological literature does not support the popular opinion that sitting-while-at-work is associated with LBP.

The Association Between Physical Workload and Low Back Pain Clouded by the "Healthy Worker" Effect : Population-Based Cross-Sectional and 5-Year Prospective Questionnaire Study

Study Design. A population-based cross-sectional and 5-year prospective questionnaire study. Objective. To investigate self-reported physical workload as a risk factor for low back pain. Summary of Background Data. Both physical and psychosocial workplace factors are considered risk factors for low back pain. However, today no consensus has been reached regarding the exact role of these factors in the genesis of low back pain. Methods. Questionnaire data were collected at baseline for 1397 (and after 5 years for 1163) men and women aged 31–50 years at baseline. Low back pain (“any low back pain within the past year,” “low back pain ≤ 30 days in total during the past year,” “low back pain > 30 days in total during the past year”) was analyzed in relation to physical workload (sedentary, light physical, and heavy physical work) using logistic regression and controlling for age, gender, and social group. The proportions of workers changing between the workload groups over the 5-year period were analyzed in relation to low back pain status. Results. At baseline no statistically significant differences in low back pain outcomes were found for workers exposed to sedentary, light physical, or heavy physical work. This was true for all age, gender, and social groups. At follow-up there was a statistically significant dose–response association between any low back pain and longstanding low back pain within the past year and increasing physical workload at baseline also after controlling for age, gender, and social group. Subjects with heavy physical workload at baseline changed statistically significantly more often to sedentary work if they experienced low back pain for more than 30 days out of the past year. Conclusions. Having a sedentary job might have a protective or neutral effect in relation to low back pain, whereas having a heavy physical job constitutes a significant risk factor. Because of migration between exposure groups (the “healthy-worker” effect), longitudinal studies are necessary for investigating the associations between physical workload and low back pain.

Categorising the severity of neck pain: establishment of cut-points for use in clinical and epidemiological research.

Abstract Grading pain intensity scales into simple categories provides useful information for both clinicians and epidemiologists and methods to classify pain severity for numerical rating scales have been recommended. However, the establishment of cut‐points is still in its infancy and little is known as to whether cut‐points are affected by age or gender. The objectives of this paper were to establish optimal cut‐points in pain severity in individuals with neck pain (NP) and to investigate if the cut‐points were influenced by gender, age, and NP duration. Data from the population‐based ‘Funen Neck and Chest Pain Study’ was used. Univariate and multivariate analyses of variance were performed to calculate optimal single and double cut‐points for three different pain intensity scores within the past 2 weeks relative to two neck disability scales (‘global assessment of NP’ and the ‘Copenhagen Neck Functional Disability Scale’). The two disability scales showed small differences in optimal cut‐points. Furthermore, cut‐points changed for each of the three pain intensity scales. Only small gender differences in cut‐points were seen and no specific trend was noted in either single or double cut‐points in different age groups. The cut‐points were almost identical for acute, subacute, and chronic NP. This paper has implications for understanding the impact of using different pain intensity scales and provides reference cut‐points in NP for use in future clinical and epidemiological research.