Pelvic girdle pain in pregnancy and early postpartum - prevalence and risk factors in a multi-ethnic cohort.

BACKGROUND: Pelvic girdle pain (PGP) is common during and after pregnancy. It has been assumed that Scandinavian women report more PGP than women of other ethnicities. However, there are few population-based studies on ethnic differences and few with ethnicity as risk factor for PGP. The purposes of the present study were: To examine the prevalence of self-reported PGP through pregnancy and early postpartum in a multi-ethnic cohort. To investigate how ethnicity and patient characteristics were associated with risk of PGP during pregnancy and early postpartum. To investigate if clinical and personal factors obtained in gestation week (GW) 15 were associated with PGP in GW28 and postpartum week (PPW) 14. METHODS: This study analyzed questionnaire data from 823 women from the Stork - Groruddalen mult-iethnic cohort study in Norway. Chi-square tests were used to investigate ethnic differences in prevalence of self-reported PGP, and logistic regression analyses to identify factors associated with self-reported PGP. RESULTS: Women from South-Asia and Middle East reported 10-20% higher prevalence of self-reported PGP at all time points compared with Western women. Ethnicity was associated with PGP in GW15 and PPW14, adjusted for parity. Pain locations in pelvic area (PGP locations) in GW15, especially combined symphysis and posterior PGP, gave the highest risk (OR=7.4) for PGP in GW28 and in PPW14 (OR = 3.9). Being multiparous was a risk for PGP in PPW14 (OR=1.9). CONCLUSIONS: Women of South Asian and Middle Eastern background had higher risk of self-reported PGP than Western women. Ethnicity was associated with PGP in GW15 and PPW14, after adjustments for parity. PGP locations in GW15 was the most prominent risk factor for PGP in GW28 and PPW14, whilst ethnicity was not significant in multivariable analyses.

The association between different outcome measures and prognostic factors in patients with neck pain: a cohort study.

BACKGROUND: Health domains like pain, disability, and health-related quality of life are commonly used outcomes for musculoskeletal disorders. Most prognostic studies include only one outcome, and it is unknown if prognostic factors and models may be generic across different outcomes. The objectives of this study were to examine the correlation among commonly used outcomes for neck pain (pain intensity, disability, and health-related quality of life) and to explore how the predictive performance of a prognostic model differs across commonly used outcomes. METHODS: We conducted an observational prospective cohort study with data from patients with neck pain aged 18-84 years consulting Norwegian chiropractors. We used three different outcomes: pain intensity (Numeric Pain Rating Scale), the Neck Disability Index (NDI), and health-related quality of Life (EQ-5D). We assessed associations between change in outcome scores at 12-weeks follow-up with Pearson's correlation coefficient. We used multivariable linear regression models to explore differences in explained variance and relationship between predictors and outcomes. RESULTS: The study sample included 1313 patients and 941 (72%) completed follow-up at 12 weeks. The strongest correlation was between NDI and EQ-5D (r = 0.57) while the weakest correlation was between EQ-5D and pain intensity (r = 0.39). The correlation between NDI and pain intensity was moderate (r = 0.53) In the final regression models, the explained variance ranged from adjusted R2 of 0.26 to 0.60, highest with NDI and lowest with pain intensity as outcome. The predictive contributions of the included predictors were similar across outcomes. Among the investigated predictors, pain patterns and the baseline measure of the corresponding outcome measure contributed the most to explained variance across all outcomes. CONCLUSIONS: The highest correlation was found between NDI and EQ-5D and the lowest with pain intensity. The same prognostic model showed highest predictive performance with NDI as outcome and poorest with pain intensity as outcome. These results suggest that we need more knowledge on the reasons for the differences in predictive performance variation across outcomes.

Impact of job adjustment, pain location and exercise on sick leave due to lumbopelvic pain in pregnancy: a longitudinal study.

Objective: To identify factors associated with sick leave due to lumbopelvic pain (LPP) in pregnancy. Design: Prospective cohort study using participants from a randomized controlled trial (RCT) designed to study the effect of exercise during pregnancy on pregnancy related diseases. Setting: St. Olavs Hospital, Trondheim University Hospital and Stavanger University Hospital, April 2007 to December 2009. Subjects: Healthy pregnant women. Main outcome measures: Self-reported sick leave due to LPP in late pregnancy (gestation week 32-36). Results: In total, 532/716 (74%) women reported LPP at 32-36 weeks of pregnancy, and 197/716 (28%) reported sick leave due to LPP. Not receiving job adjustments when needed (Odds ratio, OR with 95% confidence interval, CI, was 3.0 (1.7-5.4)) and having any pain in the pelvic girdle versus no pain (OR 2.7 (1.3-5.6), OR 2.7 (1.4-5.2) and OR 2.2 (1.04-4.8)) for anterior, posterior and combined anterior and posterior pain in the pelvis respectively, were associated with sick leave due to LPP in late pregnancy. Also higher disability, sick listed due to LPP at inclusion and lower education, were significant explanatory variables. There was a trend of reduced risk for sick leave due to LPP when allocated to the exercise group in the original RCT (OR 0.7 (0.4-1.0)). Conclusion: Facilitating job adjustments when required might keep more pregnant women in employment. Furthermore, pain locations in pelvic area, disability, lower education and being sick listed due to LPP in mid pregnancy are important risk factors for sick leave in late pregnancy. Key points Current awareness: More than half of pregnant women are on sick leave during pregnancy and the most frequently reported cause is lumbopelvic pain. This paper adds: Inability to make job adjustments, pain locations in pelvic area, disability and lower education level were the most important risk factors for sick leave in late pregnancy. Facilitating early job adjustment might be a precaution to keep more pregnant women in work. Allocation to an exercise group tended to reduce the risk of sick leave in late pregnancy.Registration number: Clinical trial gov (NCT00476567).

Protocol for the development of a core outcome set for pelvic girdle pain, including methods for measuring the outcomes: the PGP-COS study.

BACKGROUND: Pelvic Girdle Pain (PGP) is an important cause of disability and economic cost worldwide. There is a need for effective preventative and management strategies. Emerging studies measure a variety of outcomes rendering synthesis and translation to clinical practice difficult. A Core Outcome Set (COS) can address this problem by ensuring that data are relevant, useful and usable for making well-informed healthcare choices. The aim of this study is to develop a consensus-based PGP-COS, including agreement on methods (e.g. instruments) for measuring the construct outcomes in the COS for use in research and clinical practice. Furthermore, as there is uncertainty as to whether incorporating stakeholder interviews in addition to conducting a systematic review to determine an initial list of outcomes for the Delphi survey, or, whether using different rating scales in a Delphi survey impacts on the final COS, we propose to embed two methodological studies within the PGP-COS development process to address these questions. METHODS: The PGP-COS study will include five phases: (1) A systematic review of the literature and semi-structured interviews with 15 patients (three countries) to form the initial list of outcomes for the Delphi survey; (2) A 3-round Delphi including patients, clinicians, researchers and service providers; (3) A systematic review of methods for measuring the outcomes in the preliminary PGP-COS identified in the Delphi survey; (4) A face-to-face consensus meeting to agree on the final PGP-COS and methods for measuring the COS; (5) Global dissemination. To address the methodological questions, we will assess the number and type of outcomes, in the final PGP-COS, that were exclusively derived from the interviews. Secondly, we will randomise Delphi survey participants to either a 5-point or 9-point importance rating scale, and examine potential differences in 'important' ratings between the groups. DISCUSSION: There is currently no COS for measuring/monitoring PGP in trials and clinical practice. A PGP-COS will ensure that relevant outcomes are measured using appropriate measurement instruments for patients with PGP globally. CORE OUTCOME SET REGISTRATION: This PGP-COS was registered with COMET (Core Outcome Measures for Effectiveness Trials) in January 2017 ( http://www.comet-initiative.org/studies/details/958 ).

Characteristics, course and outcome of patients receiving physiotherapy in primary health care in Norway: design of a longitudinal observational project.

BACKGROUND: Physiotherapists (PTs) in primary health care manage patients with large variation in medical diagnosis, age, functional status, disability and prognosis. Lack of knowledge and systematically collected data from patients treated by PTs in primary health care has prompted this longitudinal observational physiotherapy project. This paper aims to describe a method for developing a database of patients managed by PTs in primary health care, with the main purpose to study patients' characteristics, treatment courses and prognostic factors for favourable outcome. METHODS: This is a longitudinal observational project, following patients through their physiotherapy treatment periods in primary health care in Norway and until one year after inclusion. The project involves both private practitioners and municipally employed PTs working in primary health care in nine municipalities in Norway. The patients are recruited to three different cohorts depending on age and whether they are referred to a private practitioner or a municipally employed PT. All data are recorded electronically, transferred and stored securely. For all patients we have included extensive questionnaires to obtain information about demographics, disability and function, pain-related variables, psychosocial factors, treatments and evaluation of treatment as well as response to clinical tests. The PTs have access to use their own patients' data. We have also prepared for linkage to national patient registers and data collected in population-based studies to be able to gather further important data. DISCUSSION: This project will have important implications for physiotherapy services in primary health care. The database contains more than 3000 patients, and data collection is ongoing. Data collected so far suggest that the patients included are representative of the larger population of patients treated by private practitioners or municipally employed PTs in Norway. This large scale prospective physiotherapy project will provide knowledge about the patient groups, applied treatments and short- and long-term outcome of the patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03626389 . Registered on August 13th 2018 (retrospectively registered).

Post-exertional malaise in daily life and experimental exercise models in patients with myalgic encephalomyelitis/chronic fatigue syndrome.

Post-exertional malaise (PEM) is commonly recognized as a hallmark of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and is often used as one of several criteria for diagnosing ME/CFS. In this perspective paper we want to reflect on how PEM is understood, assessed, and evaluated in scientific literature, and to identify topics to be addressed in future research. Studies show that patients use a wide variety of words and concepts to label their experience of PEM in everyday life, and they report physical or mental exertions as triggers of PEM. They also report that PEM may have an immediate or delayed onset and may last from a few days to several months. When standardized exercise tests are used to trigger PEM experimentally, the exacerbation of symptoms has a more immediate onset but still shows a wide variability in duration. There are indications of altered muscular metabolism and autonomic nervous responses if exercise is repeated on successive days in patients with ME/CFS. The decreased muscular capacity appears to be maintained over several days following such controlled exercise bouts. These responses may correspond to patients' experiences of increased exertion. Based on this background we argue that there is a need to look more closely into the processes occurring in the restitution period following exercise, as PEM reaches the peak in this phase.

Clinical indicators for recommending continued care to patients with neck pain in chiropractic practice: a cohort study.

BACKGROUND: Chiropractors' clinical indicators for recommending preventive continued care to patients with low back pain include previous pain episodes, a history of long pain duration and improvement after initial treatment. Our objectives were, in a cohort of patients with neck pain, to examine whether these clinical indicators were associated with being recommended continued care beyond 4 weeks, and if so whether this recommendation was dependent of chiropractor characteristics, as well as if the number of clinical indicators influenced this recommendation. METHODS: In this multi-center observational study, 172 patients seeking care for a new episode of neck pain in chiropractic practice in Norway were included between September 2015 and May 2016. The chiropractors treated their patients as per usual, and for this study, baseline data and 4-week follow-up data were used. Patient data included the clinical indicators (1) previous episodes of neck pain, (2) a history of long duration neck pain and (3) improvement four weeks after initial treatment. The recruiting chiropractors were asked at 4-week follow-up if each patient was recommended continued care, defined as care planned beyond the first 4 weeks. Univariate and multivariable logistic regression models investigated the association between clinical indicators and the continued care recommendation, as well as the influence of chiropractor characteristics on this recommendation. Cross tabulations investigated the relationship between the number of indicators present and recommendation of continued care. RESULTS: Long duration of neck pain was the strongest clinical indicator for being recommended continued care 4 weeks after the initial treatment. Chiropractor characteristics were not associated with this recommendation. In patients with all three clinical indicators present, 39% were recommended continued care. When two and one indicators were present, the percentages of those recommended continued care were 25% and 10%, respectively. CONCLUSION: Chiropractors recommended continued care for patients experiencing neck pain based on their history of long pain duration, and this was not influenced by characteristics of the chiropractor. This differs from previous studies of indicators for maintenance care in patients with low back pain.

Shoulder patients in primary and specialist health care. A cross-sectional study.

OBJECTIVES: Shoulder pain is a prevalent problem and has a considerable impact on the use of primary and specialist health care in Norway. It is important to improve short-term recovery and reduce long-term consequences regarding pain and disability, the high costs of treatment and the amount of sick-leave. Treatment for non-specific shoulder pain is mainly non-operative. The aims of this study were to investigate if there are differences in main characteristics, pain and disability (SPADI-score) and psycho-social factors between patients in primary and specialist health care. METHODS: This cross-sectional study included patients consulting physiotherapy in primary health care and patients at an outpatient clinic in specialist health care. Well-known and tested questionnaires for these populations were used and variables were divided into clinical, sociodemographic, psycho-social, and shoulder pain and disability. Descriptive statistics were applied. Two-sample t-test and linear regression were used for continuous data whereas chi-square tests and logistic regression were applied to test differences in categorical data between the two study populations. RESULTS: Two hundred and 36 patients were recruited from primary health care (FYSIOPRIM, Physiotherapy In Primary Care) and 167 from specialist health care. Patients in primary health care reported less regular use of pain medication (30.7 vs. 61.3%) and fewer patients had symptom duration >12 months (41.9 vs. 51.0%). Furthermore, they reported lower pain intensity, less shoulder pain and disability (SPADI-score), lower scores on psycho-social factors, but higher on expectations of recovery. CONCLUSIONS: Patients with shoulder pain treated in primary health care and in specialist health care are different according to factors such as duration of symptoms, pain and disability, and some of the psycho-social variables. However, the differences are small and the variations within the two study samples is large. Patients treated in primary health care seemed to be less affected and to have higher expectations concerning their recovery. However, based on our results we may question why many patients are referred to specialist health care rather than continuing treatment in primary health care.

Pelvic girdle pain--associations between risk factors in early pregnancy and disability or pain intensity in late pregnancy: a prospective cohort study.

BACKGROUND: Recent studies have shown high prevalence rates for pelvic girdle pain (PGP) in pregnancy. Some risk factors for developing PGP have been suggested, but the evidence is weak. Furthermore there is almost no data on how findings from clinical examinations are related to subsequent PGP. The main purpose for this study was to study the associations between socio-demographical, psychological and clinical factors measured at inclusion in early pregnancy and disability or pain intensity in gestation week 30. METHODS: This is a prospective cohort study following women from early to late pregnancy. Eligible women were recruited at their first attendance at the maternity care unit. 268 pregnant women answered questionnaires and underwent clinical examinations in early pregnancy and in gestation week 30. We used scores on disability and pain intensity in gestation week 30 as outcome measures to capture the affliction level of PGP. Multiple linear regression analysis was used to study the associations between potential risk factors measured in early pregnancy and disability or pain intensity in gestation week 30. RESULTS: Self-reported pain locations in the pelvis, positive posterior pelvic pain provocation (P4) test and a sum of pain provocation tests in early pregnancy were significantly associated with disability and pain intensity in gestation week 30 in a multivariable statistic model. In addition, distress was significantly associated with disability. The functional active straight leg raise (ASLR) test, fear avoidance beliefs and the number of pain sites were not significantly associated with either disability or pain intensity. CONCLUSIONS: The results suggest that a clinical examination, including a few tests, performed in early pregnancy may identify women at risk of a more severe PGP late in pregnancy. The identification of clinical risk factors may provide a foundation for development of targeted prevention strategies.

Trunk, pelvic and hip kinematics during the Stork test in pregnant women with pelvic girdle pain, asymptomatic pregnant and non-pregnant women.

BACKGROUND: Pelvic girdle pain is prevalent during pregnancy, and women affected report weight-bearing activities to be their main disability. The Stork test is a commonly used single-leg-stance test. As clinicians report specific movement patterns in those with pelvic girdle pain, we aimed to investigate the influence of both pregnancy and pelvic girdle pain on performance of the Stork test. METHODS: In this cross-sectional study, 25 pregnant women with pelvic girdle pain, 23 asymptomatic pregnant and 24 asymptomatic non-pregnant women underwent three-dimensional kinematic analysis of the Stork test. Linear mixed models were used to investigate between-group differences in trunk, pelvic and hip kinematics during neutral stance, weight shift, leg lift and single leg stance. FINDINGS: Few and small significant between-group differences were found. Pregnant women with pelvic girdle pain had significantly less hip adduction during single leg stance compared to asymptomatic pregnant women (estimated marginal means (95% confidence intervals) -1.1° (-2.4°, 0.3°) and 1.0° (-0.4°, 2.4°), respectively; P = 0.03). Asymptomatic pregnant women had significantly less hip internal rotation compared to non-pregnant women 4.1° (1.6°, 6.7°) and 7.9° (5.4°, 10.4°), respectively (P = 0.04) and greater peak hip flexion angle of the lifted leg in single leg stance 80.4° (77.0°, 83.9°) and 74.1° (70.8°, 77.5°), respectively (P = 0.01). Variation in key kinematic variables was large across participants in all three groups. INTERPRETATION: Our findings indicate that trunk, pelvic and hip movements during the Stork test are not specific to pregnancy and/or pelvic girdle pain in the 2nd trimester. Instead, movement strategies appear unique to each individual.

Novel approach towards musculoskeletal phenotypes.

BACKGROUND: The multidimensional array of clinical features and prognostic factors makes it difficult to optimize management within the heterogeneity of patients with common musculoskeletal pain. This study aimed to identify phenotypes across prognostic factors and musculoskeletal complaints. Concurrent and external validity were assessed against an established instrument and a new sample, respectively, and treatment outcome was described. METHODS: We conducted a longitudinal observational study of 435 patients (aged 18-67 years) seeking treatment for nonspecific complaints in the neck, shoulder, low back or multisite/complex pain in primary health care physiotherapy in Norway. Latent class analysis was used to identify phenotypes based on 11 common prognostic factors within four biopsychosocial domains; pain, beliefs and thoughts, psychological and activity and lifestyle. RESULTS: Five distinct phenotypes were identified. Phenotype 1 (n = 77, 17.7%) and 2 (n = 142, 32.6%) were characterized by the lowest scores across all biopsychosocial domains. Phenotype 2 showed somewhat higher levels of symptoms across the biopsychosocial domains. Phenotype 3 (n = 89, 20.5%) and 4 (n = 78, 17.9%) were more affected across all domains, but phenotype 3 and 4 had opposite patterns in the psychological and pain domains. Phenotype 5 (n = 49, 11.3%) were characterized by worse symptoms across all domains, indicating a complex phenotype. The identified phenotypes had good external and concurrent validity, also differentiating for the phenotypes in function and health-related quality of life outcome at 3-month follow-up. CONCLUSION: The phenotypes may inform the development of targeted interventions aimed at improving the treatment efficiency in patients with common musculoskeletal disorders. SIGNIFICANCE: This observational prospective study identified five distinct and clinically meaningful phenotypes based on biopsychosocial prognostic factors across common musculoskeletal pain. These phenotypes were independent of primary pain location, showed good external validity, and clear variation in treatment outcome. The findings are particularly valuable as they describe the heterogeneity of patients with musculoskeletal pain and points to a need for more targeted interventions in common musculoskeletal disorders to improve treatment outcome.

Prognostic factors for recovery from postpartum pelvic girdle pain.

Pelvic girdle pain (PGP) has a high incidence during pregnancy and in some women pain will persist for years. Most studies have used pain as the outcome measure, and little attention is given to functioning or disability. A better understanding of prognostic factors for recovery seems important for clinical care and treatment. The aim of the present paper was to identify prognostic factors for recovery from postpartum PGP and disability, and to determine the impacts of prognostic factors when pain intensity and disability are used as outcome measures. Seventy-eight women with diagnosed PGP were included 6-16 weeks postpartum. Possible prognostic factors were obtained through clinical tests and questionnaires at baseline. The clinical tests were posterior pelvic pain provocation (P4) test, active straight leg raise (ASLR) test and pain provocation of long dorsal sacroiliac ligament (LDL). One year postpartum outcome measures were obtained by Oswestry disability index (ODI ver 2.0) and worst evening pain (VAS 0-100). Multiple linear regression and logistic regression analyses were used to identify significant prognostic factors. At baseline 60% believed they would recover and 40% were uncertain or believed they would not recover. Fifty per cent had a history of low back pain (LBP), and 20% had high emotional distress (HSCL25-item > or =1.75). About 75% had positive LDL and P4 at both sides and 24% had pain located to all three pelvic joints. Forty per cent had ASLR scores of at least 4 (sum score range 0-10). Multivariate analyses showed consistently that ASLR and belief in improvement were statistical significant predictors for both disability and pain as outcome measures. ASLR score <4 predicted 10 points lower ODI and 19 points lower evening pain compared with having ASLR score of at least 4. Pain location was a statistical significant predictor in only one analysis. History of LBP or high psychological distress was not prognostic for recovery. ASLR test and belief in improvement are predictors of clinical significance in women having PGP postpartum.

The effects of High- versus Moderate-Intensity Exercise on Fatigue in Sarcoidosis.

BACKGROUND: Fatigue is a common symptom in patients with sarcoidosis. Despite lacking evidence on whether high-intensity interval training (HIIT) will aggravate fatigue, moderate-intensity exercise is often recommended. This study aimed to investigate whether a single session of HIIT would affect fatigue differently from a single session of moderate-intensity continuous training (MICT). METHODS: Forty-one patients with pulmonary sarcoidosis were recruited to a cross-over study. All patients completed one treadmill session of HIIT (85% of peak heart rate (HRpeak)) and one of MICT (70% of HRpeak). Fatigue was assessed with the Visual Analogue Scale 0⁻100 mm, before (T0), after (T1), and 24 hours after (T2) each exercise session. Paired sample t-test was used to compare changes in fatigue from T0 to T1 and from T0 to T2 between HIIT and MICT. RESULTS: No statistically significant difference in fatigue levels was found between HIIT and MICT, either at T1 (3.6 (13.5) and 1.4 (13.5)) or at T2 (8.2 (17.0) and 2.1 (17.1)). CONCLUSIONS: A single session of HIIT did not affect fatigue differently than a single session of MICT. These preliminary findings support the need for further research on the long-term effect of HIIT on fatigue in patients with sarcoidosis.

The Timed Up & Go test in pregnant women with pelvic girdle pain compared to asymptomatic pregnant and non-pregnant women.

BACKGROUND: The Timed Up and Go (TUG) test, a standardized functional mobility test, has been proposed as a physical performance-based measure in pregnant women with pelvic girdle pain (PGP). OBJECTIVES: This cross-sectional study aimed to investigate physical function by the use of TUG in pregnant women with PGP compared to asymptomatic pregnant and non-pregnant women, and to identify factors associated with increased TUG. METHODS: In total, 25 pregnant women with PGP, 24 asymptomatic pregnant and 25 asymptomatic non-pregnant women participated. One-way analysis of variance was used to explore difference in TUG between the groups and multiple linear regression analyses to explore associations between TUG and potential explanatory variables. RESULTS: The time on TUG varied among pregnant women with PGP, and was significantly higher (mean (95% CI) 6.9 (6.5, 7.3) seconds) than for asymptomatic pregnant (5.8 (5.5, 6.0), p < 0.001) and non-pregnant (5.5 (5.4, 5.6), p < 0.001) women. In the total study sample, group, increased BMI and sick leave were significantly associated with increased TUG (p-values≤0.02). In pregnant women with PGP, pain intensity was the only significant clinical factor associated with increased TUG (p = 0.002). CONCLUSION: Pregnant women with PGP used longer time and showed larger variation in TUG than asymptomatic pregnant and non-pregnant women, this underpins that TUG targets activities relevant to PGP. Our results provide new knowledge about factors influencing TUG time. Importantly, multivariable analyses suggest that pain intensity should be considered when interpreting TUG time in pregnant women with PGP.

Kinematic and spatiotemporal gait characteristics in pregnant women with pelvic girdle pain, asymptomatic pregnant and non-pregnant women.

BACKGROUND: Walking difficulties are common among pregnant women with pelvic girdle pain. This cross-sectional study investigated the influence of pelvic girdle pain, pregnancy and speed on spatiotemporal and trunk, pelvic and hip kinematics during gait in the 2nd trimester of pregnancy. METHODS: Three-dimensional gait analysis at self-selected speed was performed in 25 pregnant women with pelvic girdle pain, 24 asymptomatic pregnant and 24 non-pregnant women. Linear mixed models were used to investigate between-group differences in gait variables. Adjustment for gait speed was included in the analysis. Correlations between speed and fear of movement, disability and pain were examined using Spearman correlation coefficient (rs). FINDINGS: Pregnant women with pelvic girdle pain walked 18% slower (estimated marginal means (95% confidence intervals) 1.18 (1.22, 1.24) meter/s) compared to asymptomatic pregnant women (1.44 (1.38, 1.50) meter/s) (P < 0.001). Moreover, with longer double limb support (5%, P = 0.04), shorter contralateral step length (3%, P = 0.03) and more restricted pelvic and hip kinematics (0.001 ≤ P ≤ 0.01) adjusted for speed. Only stance, double limb support and thoracic rotation (0.001 ≤ P ≤ 0.04) differed between asymptomatic pregnant and non-pregnant women. Speed was negatively correlated with fear of movement (rs = -0.63, P = 0.01) and disability (rs = -0.46, P = 0.03) in the pelvic girdle pain group. INTERPRETATION: Gait is primarily influenced by pelvic girdle pain and less by pregnancy. Pregnant women with pelvic girdle pain walked slower and with a more rigid gait pattern compared to asymptomatic pregnant women, presumably related to altered load transfer. Our results may assist clinical evaluation of pelvic girdle pain, as well as direct future research.

Contraction coupling efficiency of human first dorsal interosseous muscle.

During working contractions, chemical energy in the form of ATP is converted to external work. The efficiency of this conversion, called 'contraction coupling efficiency', is calculated by the ratio of work output to energy input from ATP splitting. Experiments on isolated muscles and permeabilized fibres show the efficiency of this conversion has a wide range, 0.2-0.7. We measured the work output in contractions of a single human hand muscle in vivo and of the ATP cost of that work to calculate the contraction coupling efficiency of the muscle. Five subjects performed six bouts of rapid voluntary contractions every 1.5 s for 42 s (28 contractions, each with time to peak force < 150 ms). The bouts encompassed a 7-fold range of workloads. The ATP cost during work was quantified by measuring the extent of chemical changes within the muscle from (31)P magnetic resonance spectra. Contraction coupling efficiency was determined as the slope of paired measurements of work output and ATP cost at the five graded work loads. The results show that 0.68 of the chemical energy available from ATP splitting was converted to external work output. A plausible mechanism to account for this high value is a substantially lower efficiency for mitochondrial ATP synthesis. The method described here can be used to analyse changes in the overall efficiency determined from oxygen consumption during exercise that can occur in disease or with age, and to test the hypothesis that such changes are due to reduced contraction coupling efficiency.

Prognostic factors in first-time care seekers due to acute low back pain.

There is limited knowledge on prognostic factors for developing chronic low back pain (LBP) at an early stage of LBP. The objectives of this study were to investigate the clinical course of pain and disability, and prognostic factors for non-recovery after 1-year, in patients seeking help for the first time due to acute LBP. An inception cohort study included 123 patients with acute LBP lasting less than 3 weeks and consulting primary care for the first time. Main outcome measures were pain intensity, Roland-Morris disability questionnaire (RMQ), and sickness absence. Eleven patients (9%) did not return for the 12-month follow-up. There were large and significant reductions in pain intensity (P<0.001) and RMQ scores (P<0.001) during follow-up. Patients with neurological signs showed significantly less improvement in pain (P=0.001) and RMQ (P=0.004) compared with those without neurological signs. The proportions with sickness absence due to LBP at 6, 9, and 12 months were 7%, 8%, and 9%, respectively. At 12 months, 17% of patients had not fully recovered. Multivariate logistic regression analyses showed that high scores on a psychosocial screening (acute low back pain screening questionnaire) and emotional distress (Hopkin's symptom check list) were significantly associated with non-recovery at 12 months, with odds ratios of 4.4 (95% confidence interval 1.1-17.4) and 3.3 (1.1-10.2), respectively.

Screening for yellow flags in first-time acute low back pain: reliability and validity of a Norwegian version of the Acute Low Back Pain Screening Questionnaire.

OBJECTIVES: The purpose of this study was to evaluate the reliability and construct and predictive validity of the Norwegian version of the Acute Low Back Pain Screening Questionnnaire (ALBPSQ). METHODS: A prospective study with a 12-month follow-up was conducted on 123 patients with acute low back pain (LBP) seeking help in primary health care for the first time and 50 patients with chronic LBP for more than 3 months. RESULTS: Test-retest reliability was high with intraclass correlation coefficients of 0.90, minimal detectable change of 12 points (of a total score of 210), and coefficient of variation of 4%. Internal consistency was 0.95. Principal-components analysis revealed 3 factors explaining 49% of the variance. The ALBPSQ score correlated highly (r> or =0.60) with disability variables, moderately (0.30

Reliability, validity and responsiveness of the fear-avoidance beliefs questionnaire: methodological aspects of the Norwegian version.

OBJECTIVE: To evaluate reliability, validity and responsiveness of the Fear-Avoidance Beliefs Questionnaire (FABQ) for use in Norwegian patients with low back pain. DESIGN: A prospective cohort study with 2 groups. PATIENTS: The questionnaire was tested in 123 patients with acute low back pain and 50 patients with chronic low back pain. METHODS: A translation and cross-cultural adaptation was performed. Test-retest reliability was assessed in 28 patients with chronic low back pain. Responsiveness was assessed in acute low back pain. RESULTS: Two factors for the FABQ were confirmed; fear-avoidance beliefs about work (FABQ-Work) and physical activity (FABQ-PA), accounting for 60% and 54% of the total variance in acute and chronic low back pain, respectively. For FABQ-Work and FABQ-PA internal consistency was 0.90 and 0.79, intra-class correlation coefficients 0.82 and 0.66, minimal detectable changes 12 and 9 points, and coefficients of variation were 16% and 23%. The FABQ correlated weakly to moderately with pain, disability, distress, and clinical variables. Standardized response means were low for FABQ-Work (0.32) and moderate (0.56) for FABQ-PA. Both FABQ subscales showed initially floor and/or ceiling effects. CONCLUSION: The Norwegian FABQ version had acceptable factor structure, internal consistency, test-retest reliability and construct validity. The responsiveness of the FABQ-Work was low, and for the FABQ-PA moderate, in the acute sample.

Assessment of everyday functioning in young children with disabilities: an ICF-based analysis of concepts and content of the Pediatric Evaluation of Disability Inventory (PEDI).

BACKGROUND: Assessment of everyday functioning in children may depend to a considerable extent on the framework used to conceptualise functioning and disability. The Pediatric Evaluation of Disability Inventory (PEDI) has incorporated the mediating role of the environment on disability, using different measurement scales. The construction of the Functional Skills scales, which measure capability, and the Caregiver Assistance scales, which measure performance, was based on the Nagi disablement scheme. The International Classification of Functioning, Disability and Health (ICF) represents a new framework of functioning and disability that could be used to compare the measurement constructs and the content of different outcome measurements. PURPOSE: To examine the conceptual basis and the content of the PEDI using the ICF. METHOD: Phrases that describe the conceptual basis of the PEDI scales and of the ICF classifications were systematically collected and compared. Two researchers classified the item content of the Functional Skills scales independently before consensus was reached. RESULTS: The analyses indicate that the conceptual basis of the PEDI scales to a large extent match the ICF concepts of activity, participation and environmental factors. Both the PEDI and the ICF use the constructs of capacity and performance, but differ in how to operationalise these constructs. The classification of the Functional Skills scales shows that the PEDI primarily is a measure of activities and participation. The frequently use of environmental codes to classify the context of the requested functions demonstrates that the PEDI has incorporated the environment into the assessment. CONCLUSIONS: Our analyses indicate that the ICF could serve as a conceptual framework to clarify the measurement construct of the PEDI scales, and as taxonomy to describe and clarify the item content of the Functional Skills scales. Both as framework and taxonomy the ICF showed limitations in covering functioning in early childhood.