Do rehabilitation patients with chronic low back pain meet World Health Organisation's recommended physical activity levels?

PURPOSE: Primary: to analyse the time that patients with chronic low back pain (CLBP) admitted to pain rehabilitation spent on moderate to vigorous physical activity (MVPA) and compare this to the WHO recommendations. Secondary: to explore factors that might differentiate between those who do and do not meet the recommendations. MATERIALS AND METHODS: A Cross-sectional study embedded in secondary interdisciplinary rehabilitation of adults with CLBP. PA was measured with a tri-axial accelerometer for 1 week during admission phase. Time spent in each PA level was calculated. MVPA was also analysed in ≥10 min bouts. RESULTS: Complete datasets of 4-6 days recorded accelerometery of n = 46 patients were analysed. Time spent in MVPA was on average 6.0% per day. MVPA per day in ≥10-min bouts occurred on average 0.8 times per day (sd = 0.9; min-max 0-4). Percentage of patients meeting the recommended level of MVPA was 21.7% (10/46) and 84.8% (39/46) for the 2010 and 2020 recommendations, respectively. Most demographic and clinical variables did not seem to differentiate between those who met the WHO recommendations, and those who did not. CONCLUSION: The minority of the patients (22%) met the WHO recommended MVPA level of 2010. The more lenient recommendation of 2020 was met by 85%.

Maximal aerobic capacity is associated with lifting capacity, but not with self-reported functioning measures in patients with primary chronic low back pain: a cross-sectional study.

Objective: Maximal exercise testing is considered the gold standard to assess V̇O2max. However, maximal exercise testing was previously deemed unfeasible and unsafe in chronic low back pain (CLBP) patients. Consequently, most previous studies on aerobic capacity and functioning in patients with CLBP were performed with submaximal testing protocols. A recent study demonstrated the safety, feasibility and tolerance of maximal exercise testing in patients with CLBP. Therefore, the relation between aerobic capacity and functioning should be reevaluated. This cross-sectional study aims to determine the relationship between maximal aerobic capacity and four measures of functioning: lifting capacity, work ability, pain-related disability and physical functioning in patients with CLBP. Methods: The maximal aerobic capacity of patients with CLBP was assessed with a maximal cardiopulmonary exercise test. Functioning was measured with a floor-to-waist lifting capacity test and three questionnaires: Work Ability Score, Pain Disability Index and Physical Functioning subscale of RAND-36. The associations between maximal aerobic capacity and each of the functioning measures were analysed with multiple linear regression analyses while controlling for potential confounders. Results: Data of n=74 patients with CLBP were analysed. After controlling for potential confounders, maximal aerobic capacity was moderately associated with lifting capacity (ß=0.32, p=0.006), but not with any of the other functioning measures (ß=-0.08 to 0.12, p>0.288). Conclusion: A higher level of maximal aerobic capacity is moderately associated with a higher lifting capacity, but not with self-reported work ability, pain-related disability and physical functioning.

Central sensitization and functioning in patients with chronic low back pain: A cross-sectional and longitudinal study.

BACKGROUND: Central sensitization (CS) is present in a subgroup of patients with chronic low back pain (CLBP). Studies on the relationship between CS and functioning have limited operationalizations of CS and functioning. OBJECTIVE: To determine whether CS was related to functioning in patients with CLBP (cross-sectional); and to determine whether changes in CS were related to changes in functioning (longitudinal). METHODS: An observational prospective cohort study with data collected at baseline and discharge of an interdisciplinary pain rehabilitation program was executed. CS indicators: CS Inventory part A (CSI-A), quantitative sensory testing (QST), root mean square of successive differences of heart-rate variability (RMSSD). Functioning measures: lifting capacity, physical functioning subscale of Rand36 (Rand36-PF), Work Ability Score (WAS), Pain Disability Index (PDI). Main analyses included correlation and multiple regression controlling for confounders; cross-sectional with baseline data and longitudinal with deltas (Δ). RESULTS: 76 patients with primary CLBP participated at baseline and 56 at discharge. Most associations were weak (cross-sectional r𝑝𝑎𝑟𝑡𝑖𝑎𝑙=-0.30-0.24; longitudinal r𝑝𝑎𝑟𝑡𝑖𝑎𝑙=-0.37-0.44). Cross-sectional multiple regression significant associations: mechanical pain threshold-QST and lifting capacity (r𝑝𝑎𝑟𝑡𝑖𝑎𝑙=-0.39), parasympathetic/vagal tone-RMSSD and physical functioning-Rand36-PF (r𝑝𝑎𝑟𝑡𝑖𝑎𝑙= 0.26). Longitudinal multiple regression significant associations: Δ parasympathetic/vagal tone-RMSSD and Δ lifting capacity (r𝑝𝑎𝑟𝑡𝑖𝑎𝑙= 0.48), ΔCSI-A and Δdisability-PDI (r𝑝𝑎𝑟𝑡𝑖𝑎𝑙= 0.36). Cross-sectional and longitudinal final regression models explained 24.0%-58.3% and 13.3%-38.0% of total variance. CONCLUSION: CS was weakly related to functioning, and decreases in CS were weakly-moderately related to increases in functioning.

Maximal cardiopulmonary exercise test in patients with chronic low back pain: feasibility, tolerance and relation with central sensitization. An observational study.

PURPOSE: To analyze the feasibility of and pain-related tolerance to a maximal cardiopulmonary exercise test (CPET), and the relationship between the aerobic capacity and central sensitization (CS) in patients with chronic low back pain (CLBP). METHODS: An observational study, combining a cross-sectional and a prospective 24-hour follow-up was performed. Participants underwent a maximal CPET on a cycle ergometer and were assessed with three measures of CS (CS Inventory, quantitative sensory testing and heart rate variability). Before the CPET, immediately afterwards and 24 h after, the Pain Response Questionnaire (PRQ) was filled out. The CPET was considered feasible when >80% performed maximally, and tolerable when <20% reported relevant pain increase, body reactions and additional pain medication use in the PRQ. Multiple regression analyses were applied to assess the relationship between the aerobic capacity (VO2max) and CS measures, corrected for confounders. RESULTS: 74 patients with CLBP participated of which 30 were male, mean age was 40.4 years (SD: 12.4) and median VO2max was 23.9 ml/kg/min (IQR: 18.2-29.4). CPET was completed by 92%. No serious adverse events occurred. A relevant pain increase was reported in the upper legs by 40% immediately after CPET and by 28% 24 h afterwards, 27% reported body reactions after 24 h, and 22% increased pain medication use 24 h after CPET. Very weak and not significant relations (rpartial=-0.21 to 0.05; p > 0.10) were observed between aerobic capacity and CS measures. CONCLUSIONS: A maximal CPET is feasible in patients with CLBP. Most, but not all, tolerated it well. CS was not related to aerobic capacity.Implications for rehabilitationMaximal CPET is feasible in patients with CLBP and well tolerated by most patients.Maximal CPET can be safely applied to assess the aerobic capacity of patients with CLBP.Aerobic capacity is unrelated to central sensitization.Outcomes of a maximal CPET and the pain response to straining activity can be used to provide valid information for the decision-making of exercise therapy.

Lifting capacity is associated with central sensitization and non-organic signs in patients with chronic back pain.

PURPOSE: To analyze the associations between lifting capacity, and central sensitization (CS) and non-organic signs (NOS) in patients with chronic back pain (CBP) attending vocational rehabilitation. MATERIALS AND METHODS: Cross-sectional observational multicenter study among patients with CBP undergoing a return to work assessment within care as usual. Main analyses: step 1: partial correlation between lifting capacity, and CS, NOS, and additional variables; step 2: multiple regression in stepwise forward method for dependent variable lifting capacity, and for independent variables CS and NOS, and additional variables significant (p < 0.05) at step 1. All analyses were controlled for sex. RESULTS: Fifty-six patients of mean age 42.5 years and 59% women participated in the study. Correlations between lifting capacity and CS and NOS were r = -0.53 and r = -0.50, respectively. CS and NOS, as well as age and sex, contributed significantly to the final regression model, which explained 57.6% of variance. CONCLUSIONS: After controlling for confounders, CS and NOS were negatively associated with lifting capacity in patients with CBP. Explained variance was substantially higher than previously reported studies.Implications for RehabilitationThe identification of central sensitization and non-organic signs (NOS) in patients with chronic back pain can alert clinicians about central nervous system being in a hypersensitive state and about pain behavior.Central sensitization and NOS are relevant determinants of lifting capacity.Better understanding of the factors affecting lifting capacity lead to better design and tailoring of interventions, resulting in optimized vocational rehabilitation programs and faster return to work.

Central Sensitisation and functioning in patients with chronic low back pain: protocol for a cross-sectional and cohort study.

INTRODUCTION: A relevant subsample of patients with chronic low back pain (CLBP) have manifested augmented central pain processing, central sensitisation (CS). Patients with CLBP have limited functioning and participation. Theoretically, physical functioning in patients with CLBP can plausibly be linked to CS; however, evidence to explain such association is scarce. Moreover, there is no gold standard for CS diagnosis. The objectives of the study are: (1) to analyse the association between instruments assessing reference symptoms and signs attributed to CS; (2) to analyse whether reference symptoms and signs attributed to CS are associated with functioning measurement outcomes; and (3) to analyse whether changes (between baseline and discharge) in reference symptoms and signs attributed to CS are related to changes in each of the functioning measurement outcomes. METHODS AND ANALYSIS: A cross-sectional and longitudinal observational study is performed with measurements taken at baseline and discharge of an interdisciplinary rehabilitation programme. A sample size of 110 adult patients with CLBP has been calculated for the study. CS measurements are: Central Sensitisation Inventory, quantitative sensory testing and heart rate variability. Functioning measurements are: lifting capacity, maximal aerobic capacity, accelerometry and reported functioning. Statistical analyses to be performed are: (1) correlation between CS measurements, (2) multiple regression between functioning (dependent variable) and CS measurements (independent variable), and (3) multiple regression between changes in scores of functioning (dependent variable) and CS measurements (independent variable), and corrected for sex and age. ETHICS AND DISSEMINATION: The study obtained the clearance to its implementation from the Medical Research Ethics Committee of the University Medical Center Groningen in July 2017. The results will be disseminated through scientific publications in peer-reviewed journals, presentations at relevant conferences, and reports to stakeholders. TRIAL REGISTRATION NUMBER: NTR7167/NL6980.

Association between social factors and performance during Functional Capacity Evaluations: a systematic review.

Purpose: Determine the association of different social factors with Functional Capacity Evaluation (FCE) performance in adults. Materials and methods: A systematic literature search was performed in MEDLINE, CINAHL, and PsycINFO electronic databases. Studies were eligible if they studied social factor's association with the performance of adults undergoing FCE. Studies were assessed on methodological quality and quality of evidence. The review was performed using best-evidence synthesis methods. Results: Thirteen studies were eligible and 11 social factors were studied. Considerable heterogeneity regarding measurements, populations, and methods existed among the studies. High quality of evidence was found for the association of FCE performance with the country of FCE and examiner's fear behavior; moderate quality of evidence with previous job salary; and low or very low quality of evidence with compensation status, litigation status, type of instruction, time of day (workday), primary or mother language, and ethnicity. Other social factors were not studied. Conclusions: Evidence for associations of various social factors with FCE performance was found, but robust conclusions about the strength of the associations cannot be made. Quality of evidence ranged from high to very low. Further research on social factors, also within a biopsychosocial context, is necessary to provide a better understanding of FCE performance. Implications for Rehabilitation Research on Functional Capacity Evaluation (FCE) performance and its association with biopsychosocial factors have scarcely addressed the impact of social factors, limiting full understanding of FCE results. The social factors, healthcare (examiner's fear behavior and type of instruction), personal or cultural systems (country of FCE, primary or mother language, and ethnicity), workplace system (previous job salary, time of day (workday)), and legislative and insurance system (compensation and litigation status), have a bearing in FCE performance. Better understanding of factors associating with functional capacity provide insights in FCE, allowing clinicians to improve the evaluations and interpretations of the assessment and better design the rehabilitation program. Better understanding of factors that influence FCE performance, and of unstudied factors, will allow researchers guidance to further investigate the construct of functional capacity.

Functional Capacity Evaluation in Different Societal Contexts: Results of a Multicountry Study.

Purpose To examine factors associated with Functional Capacity Evaluation (FCE) results in patients with painful musculoskeletal conditions, with focus on social factors across multiple countries. Methods International cross-sectional study was performed within care as usual. Simple and multiple multilevel linear regression analyses which considered measurement's dependency within clinicians and country were conducted: FCE characteristics and biopsychosocial variables from patients and clinicians as independent variables; and FCE results (floor-to-waist lift, six-minute walk, and handgrip strength) as dependent variables. Results Data were collected for 372 patients, 54 clinicians, 18 facilities and 8 countries. Patients' height and reported pain intensity were consistently associated with every FCE result. Patients' sex, height, reported pain intensity, effort during FCE, social isolation, and disability, clinician's observed physical effort, and whether FCE test was prematurely ended were associated with lift. Patient's height, Body Mass Index, post-test heart-rate, reported pain intensity and effort during FCE, days off work, and whether FCE test was prematurely ended were associated with walk. Patient's age, sex, height, affected body area, reported pain intensity and catastrophizing, and physical work demands were associated with handgrip. Final regression models explained 38‒65% of total variance. Clinician and country random effects composed 1-39% of total residual variance in these models. Conclusion Biopsychosocial factors were associated with every FCE result across multiple countries; specifically, patients' height, reported pain intensity, clinician, and measurement country. Social factors, which had been under-researched, were consistently associated with FCE performances. Patients' FCE results should be considered from a biopsychosocial perspective, including different social contexts.

Correction to: Functional Capacity Evaluation in Different Societal Contexts: Results of a Multicountry Study.

The original version of this article unfortunately contained a mistake in the Table 2. The data under column head "Left handgrip strength (n = 336)" was erroneously omitted during the production process. The corrected Table 2 is given below.

Age-related differences in women's foot shape.

PURPOSE: Describe age-related differences in women's foot shape using a wide range of measurements and ages. STUDY DESIGN: Cross-sectional, observational study. MAIN OUTCOME MEASUREMENTS: Six foot-shape measurements of each foot: foot lengths, ball widths, ball circumferences, low instep circumferences, high instep circumferences, and heel instep circumference. RESULTS: 168 women from 20 to over 80 years of age, divided into seven age categories, were included. Older women had significantly greater foot-shape measurements, even after adjusting for Body Mass Index. Ball widths increased 3.1-4.0mm per decade, ball circumferences 5.6-7.4mm per decade, high instep circumferences 0.4-4.8mm per decade, and heel instep circumferences 1.8-1.9mm per decade. Ball widths, ball circumferences, and left high instep circumference plateaued in the 70-75 years-of-age category, and decreased in the oldest age category. For low instep circumference, age did not prevail significantly over Body Mass Index. Foot length was not associated with age. CONCLUSION: This study described women's progressive foot-shape changes with age. The findings provide a better understanding of foot-shape changes, mainly found in the forefoot. It demonstrates that for a good fit, shoe design for older adults and for younger adults should differ.