Discrepancies in assessing home care workers' working conditions in a Norwegian home care service: differing views of stakeholders at three organizational levels.

BACKGROUND: The present study is a follow-up study of factors contributing to an undesirable quality of work environment and sick leave rate in the home care services in a Norwegian municipality. The underlying assumption is that organizational discrepancies in the perceptions and appraisals of significant factors and processes in an organization have detrimental effects on the management of the organization and on work environment conditions. Thus, the study aim is to explore potential organizational discrepancies in the appraisals of factors relating to home care workers' working conditions. METHODS: The study, using a mixed-methods design, comprised six home care units. It included survey responses of home care workers (80 respondents, response rate 54 %) and qualitative descriptions of stakeholders' appraisals of organizational issues gathered through semi-structured interviews (33 interviews with stakeholders at three organizational levels). RESULTS: Employees at different organizational levels in the home care services expressed divergent appraisals of factors related to the working conditions of home care workers, including impact of organizational measures (i.e. time pressure, work tasks, a new work program, organizational changes, budget model, budget allocation and coping strategies). Survey responses supported interview descriptions by home care workers. Results suggest that organizational discrepancy serve as an important barrier to a sustainable, well-functioning organization in general and to quality-enhancing changes to work procedures in particular. CONCLUSIONS: It is recommended to improve communication channels and facilitate the exchange of information across levels to ensure a common understanding of matters significant to the organization of the home care services and to the work environment of home care workers. The prevalence and impact of organizational discrepancy should be included in organization research, particularly when exploring explanatory factors of an unhealthy organization.

Understanding significant processes during work environment interventions to alleviate time pressure and associated sick leave of home care workers--a case study.

BACKGROUND: Ergonomic and work stress interventions rarely show long-term positive effect. The municipality participating in this study received orders from the Norwegian Labour Inspectorate due to an identified unhealthy level of time pressure, and responded by effectuating several work environment interventions. The study aim is to identify critical factors in the interaction between work environment interventions and independent rationalization measures in order to understand a potential negative interfering effect from concurrent rationalizations on a comprehensive work environment intervention. METHODS: The study, using a historic prospective mixed-method design, comprised 6 home care units in a municipality in Norway (138 respondents, response rate 76.2%; 17 informants). The study included quantitative estimations, register data of sick leave, a time line of significant events and changes, and qualitative descriptions of employee appraisals of their work situation gathered through semi-structured interviews and open survey responses. RESULTS: The work environment interventions were in general regarded as positive by the home care workers. However, all units were simultaneously subjected to substantial contextual instability, involving new work programs, new technology, restructurings, unit mergers, and management replacements, perceived by the home care workers to be major sources of stress. Findings suggest that concurrent changes induced through rationalization resulted in negative exposure effects that negated positive work environment intervention effects, causing an overall deteriorated work situation for the home care workers. CONCLUSIONS: Establishment and active utilization of communication channels from workers to managers are recommended in order to increase awareness of putative harmful and interruptive effects of rationalization measures.

Cardiovascular responses to cognitive stress in patients with migraine and tension-type headache.

BACKGROUND: The purpose of this study was to investigate the temporal relationship between autonomic changes and pain activation in migraine and tension-type headache induced by stress in a model relevant for everyday office-work. METHODS: We measured pain, blood pressure (BP), heart rate (HR) and skin blood flow (BF) during and after controlled low-grade cognitive stress in 22 migraineurs during headache-free periods, 18 patients with tension-type headache (TTH) and 44 healthy controls. The stress lasted for one hour and was followed by 30 minutes of relaxation. RESULTS: Cardiovascular responses to cognitive stress in migraine did not differ from those in control subjects. In TTH patients HR was maintained during stress, whereas it decreased for migraineurs and controls. A trend towards a delayed systolic BP response during stress was also observed in TTH. Finger BF recovery was delayed after stress and stress-induced pain was associated with less vasoconstriction in TTH during recovery. CONCLUSION: It is hypothesized that TTH patients have different stress adaptive mechanisms than controls and migraineurs, involving delayed cardiovascular adaptation and reduced pain control system inhibition.

Autonomic and muscular responses and recovery to one-hour laboratory mental stress in healthy subjects.

BACKGROUND: Stress is a risk factor for musculoskeletal pain. We wanted to explore stress related physiology in healthy subjects in order to gain insight into mechanisms of pain development which may relate to the pathophysiology of musculoskeletal pain disorders. METHODS: Continuous blood pressure, heart rate, finger skin blood flow, respiration, surface electromyography together with perception of pain, fatigue and tension were recorded on 35 healthy women and 9 healthy men before, during a 60 minute period with task-related low-grade mental stress, and in the following 30 minute rest period. RESULTS: Subjects responded physiologically to the stressful task with an increase in trapezius and frontalis muscle activity, increased blood pressure, respiration frequency and heart rate together with reduced finger skin blood flow. The blood pressure response and the finger skin blood flow response did not recover to baseline values during the 30-minute rest period, whereas respiration frequency, heart rate, and surface electromyography of the trapezius and frontalis muscles recovered to baseline within 10 minutes after the stressful task. Sixty-eight percent responded subjectively with pain development and 64% reported at least 30% increase in pain. Reduced recovery of the blood pressure was weakly correlated to fatigue development during stress, but was not correlated to pain or tension. CONCLUSION: Based on a lack of recovery of the blood pressure and the acral finger skin blood flow response to mental stress we conclude that these responses are more protracted than other physiological stress responses.

Low-amplitude trapezius activity in work and leisure and the relation to shoulder and neck pain.

The aim of this study is to obtain evidence supporting or negating the hypothesis that muscle pain is associated with sustained activation of low-threshold motor units. Long-term surface electromyographic (EMG) recordings of trapezius activity pattern were related to subjectively reported shoulder and neck pain in work and leisure. Recordings from 118 female subjects (73 recorded both during work and leisure) were analyzed. Computer operators, secretaries, and health care and retail workers were represented in the material. The recordings were calibrated by the root-mean-square-detected response at maximal voluntary contraction (%maximum EMG). The analysis was performed by quantifying duration and amplitude of surface EMG activity exceeding 2% maximum EMG ("EMG bursts"). Three response categories were defined by duration of the burst periods during work: low- (<50%), intermediate- (50-70%), and high-response (>70%) groups. Shoulder and neck pain was assessed by hourly visual analog score throughout work and leisure and by pain score for the last 6 mo. Shoulder and neck pain was higher at work than leisure for subjects with long-term pain in both the high- and the low-response groups. Persistent pain, defined by the 6-mo score, was more prevalent in the high- than the low- and intermediate-response groups (73 vs. 37%); relative risk was 2.0. Trapezius activity was reduced from work to leisure for the high- but not the low-response group. The activity pattern is consistent with low-threshold motor unit overexertion for the high- but not the low-response group. We speculate that different mechanisms of muscle pain causation, dependent and independent of motor activity pattern, coexist.

Long-term electromyographic activity in upper trapezius and low back muscles of women with moderate physical activity.

The habitual activity patterns of trapezius and postural back muscles (multifidus, iliocostalis, longissimus) of 23 female subjects with moderate physical activity were studied. Bilateral surface electromyographic (sEMG) recordings from start of work until bedtime were analyzed. The activity level was calibrated as percentage of root mean square-detected muscle activity at maximal voluntary contraction (EMG(max)). Sixty-six previous trapezius recordings of women with moderate physical activity were included in some analyses to pursue the full range of variation in trapezius activity. Twenty-six of these were recorded twice, separated by 16-28 mo. Median activity level and duration of periods with sEMG activity of <0.5% EMG(max) ("rest time"; only trapezius) and exceeding 2 ("burst time"), 10, 30, and 50% EMG(max) was determined. The trapezius median activity level ranged from 0.6 to 8.8% EMG(max), burst time from 9 to 84%, and rest time from 2 to 84%. The activity patterns of the back muscles showed similar large interindividual variation. Repeated trapezius recordings of the same subject showed high consistency; intraclass correlation coefficients ranged from 0.62 to 0.79 for different sEMG variables. Periods with high sEMG amplitude were of short duration; 7% of the trapezius recordings did not present time intervals (0.2-s duration) above 50% EMG(max). The activity patterns of the postural muscles, despite large interindividual variability, were distinctly different from activity patterns of upper and lower limb muscles reported by others (e.g., mean burst time 40-50 vs. 10-20%). We conclude that postural trunk muscles show idiosyncratic activity patterns with large interindividual variation. High-threshold motor units are activated to a very minor extent.

The activity patterns of neck muscles in professional classical singing.

The study aimed to characterize the activity patterns of neck muscles during classical singing. Muscle usage during inhalation and phonation and the relationship to changes in pitch and vocal loudness was of particular interest. Five professional opera singers (2 males, 3 females) participated. Surface electromyographic activity (EMG) was recorded from the upper trapezius (TR), the sternocleidomastoideus (STM), and the scalenus (SC) muscles and the muscles in the posterior neck region (PN). EMG activity in TR and STM was lowered by EMG biofeedback (BF), and the possible effect of lowered EMG activity in these muscles on the EMG activity of SC and PN was analyzed. A strain gauge sensor recorded the chest circumference of the thorax. Three singing tasks were performed. Each task was performed three times with variation in vocal loudness and pitch. After the first performance of the singing tasks, the BF session was carried out. Thereafter muscle activity was recorded in repeat performances of the same tasks, and the EMG amplitude of all muscles was compared before and after BF. We conclude that STM and SC showed correlated activity patterns during inhalation and phonation by classical singers. Second, substantial muscle activity was observed in PN during inhalation and phonation. BF performed on TR and STM had a secondary effect of lowering EMG activity in SC and PN. The activity of all neck muscles was markedly elevated when singing in the highest pitch. There was no consistent task-based difference in EMG amplitude for the other singing tasks.

Work demands and health consequences of organizational and technological measures introduced to enhance the quality of home care services--A subgroup analysis.

This study of home care workers in a Norwegian municipality aimed to examine the effect of two measures involving organizational (job checklists) and technological (personal digital assistants) job aids on perceived work demands and musculoskeletal health. Questionnaire data was collected in 2009 (n = 138, response rate 76.2%) and 2011 (n = 80, response rate 54%). Forty-six home care workers responded at both waves. Respondents were assigned into 'high', 'moderate' and 'low' strain groups based on their responses to open and closed survey questions regarding impact of the two measures. One-way ANOVA with post-hoc t-tests and regression analyses investigated group differences and examined development in variables. Perceived work demands and health effects over the two-year study period were unchanged overall, yet significant differences between subgroups were highlighted. Work demands and shoulder-neck pain remained high for high-strain workers, but were reduced for low and moderate strain workers. Management should be aware of diversity in worker responses to rationalizations and give priority to supplementary, targeted measures to counteract adverse effects.

Exploring perceived tension as a response to psychosocial work stress.

UNLABELLED: This study extends the concept of tension, in part by observing changes in tension during the workday, to identify episodes causing elevated tension and relate them to bodily responses. Methods Both questionnaires and qualitative interviews were used to describe the tension concept. Tension was scored on a visual analogue scale (VAS) every hour, and trapezius muscle activity and heart rate were recorded. Ninety-four female workers from four service occupations participated. RESULTS: Tension was described as a musculoskeletal activation response involving the upper body regions, but also autonomic activation responses were described. The cause of elevated tension comprised a variety of situational demands; however, contact with other people causing negative emotions was a common factor. Averaged muscular activity and heart rate responses did not correlate with prolonged perceived tension, but the differential tension score between high- and low-tension periods correlated with the corresponding differential trapezius activity responses. The regression line indicated no effect of short-term variation in perceived tension on median muscle activity for differential VAS scores of < or = 2 cm. An increase of 2% of maximal electromyographic activity for a differential VAS score of 4-5 cm was indicated. CONCLUSIONS: This study identifies work exposures that cause tension, and it demonstrates a physiological correlate with the subjective perception of tension in the short term. The low recorded muscle activationresponse does not represent a risk factor for pain by the traditional standards used for recording and evaluating muscle activity responses, but it may point to underlying pain-inducing mechanisms, such as low-threshold overexertion of motor units.

Perceived occupational exposures of home care workers and the association to general tension, shoulder-neck and low back pain.

BACKGROUND: Home care workers are at risk of various harmful occupational exposures, health complaints and sick leave. OBJECTIVE: Identifying occupational exposures related to shoulder-neck and low back pain, and assessing the comparative importance of such exposures, for home care workers. METHODS: One hundred and thirty-eight home care workers in a large municipality in Norway participated in the study (response rate 76.2%). Questionnaire comprised a combination of standardized items and context-specific VAS scales on mental, social, emotional and physical work demands, perceived general tension and pain in shoulder-neck and low back. RESULTS: Severe pain scores for both shoulder-neck and low back regions were common, with individual variations. All VAS measures on occupational exposures were significantly correlated with shoulder-neck pain and all except social demands were significantly correlated with low back pain. However, stronger associations were found with perceived general tension, which proved to be the strongest predictor of shoulder-neck and low back pain, indicating a mediating effect in the relationship between occupational exposures and musculoskeletal pain. CONCLUSIONS: Identifying and alleviating occupational exposures is important to ensure a healthy and sustainable work environment. Special attention should be drawn to early signs of symptoms, such as general tension, preventing further development of musculoskeletal pain.

Systematic evaluation of observational methods assessing biomechanical exposures at work.

OBJECTIVES: This systematic review aimed to identify published observational methods assessing biomechanical exposures in occupational settings and evaluate them with reference to the needs of different users. METHODS: We searched scientific databases and the internet for material from 1965 to September 2008. Methods were included if they were primarily based on the systematic observation of work, the observation target was the human body, and the method was clearly described in the literature. A systematic evaluation procedure was developed to assess concurrent and predictive validity, repeatability, and aspects related to utility. At least two evaluators independently carried out this evaluation. RESULTS: We identified 30 eligible observational methods. Of these, 19 had been compared with some other method(s), varying from expert evaluation to data obtained from video recordings or through the use of technical instruments. Generally, the observations showed moderate to good agreement with the corresponding assessments made from video recordings; agreement was the best for large-scale body postures and work actions. Postures of wrist and hand as well as trunk rotation seemed to be more difficult to observe correctly. Intra- and inter-observer repeatability were reported for 7 and 17 methods, respectively, and were judged mostly to be good or moderate. CONCLUSIONS: With training, observers can reach consistent results on clearly visible body postures and work activities. Many observational tools exist, but none evaluated in this study appeared to be generally superior. When selecting a method, users should define their needs and assess how results will influence decision-making.

Back posture and low back muscle activity in female computer workers: a field study.

BACKGROUND: Few studies have investigated sitting posture and low back muscle activity in occupational settings. This study aims to determine back posture and its influence on low back muscle activity in computer workers, and to investigate whether the work situation is associated with exacerbation of low back pain. METHODS: Twenty-one female computer workers participated. Surface electromyographic activity was recorded from lumbar multifidus, longissimus, and iliocostalis throughout the workday. Simultaneous inclinometer recordings from pelvis, upper trunk, and left thigh were used to determine back posture and identify periods with sitting, standing, and walking. Low back pain intensity was recorded by visual analogue scale every hour throughout the work and leisure periods. FINDINGS: All subjects adopted a markedly flexed back posture while seated at work. Surface electromyographic activity was very low for all muscles during sitting (group median <1.4% of root-mean-square-detected response at maximal voluntary contraction). Back posture moderately influenced electromyographic activity, accounting for 19% (sitting) to 38% (standing) of intra-individual variation in muscle activity. Subjects reporting aggravating low back pain (n=10) during the workday were not distinguished by duration of sitting, sitting posture, or low back muscle activity. Low back pain was markedly reduced from the last hour of work to the first hour of leisure, accompanied by an increase in low back muscle activity. INTERPRETATION: Low back muscle activity was very low during seated posture, presumably due to the flexion-relaxation phenomenon. Sustained stretch of passive lumbar structures in combination with essentially silent muscles may exacerbate low back pain in sedentary workers.

The influence of body posture, arm movement, and work stress on trapezius activity during computer work.

The study aimed to determine the influence of arm posture and movement on trapezius activity of computer workers, considering the full workday. A second aim was to investigate if work periods perceived as stressful were associated with elevated or more sustained muscle activity pattern. Twenty-six computer workers performing call-center (n=11), help desk (n=7), or secretarial (n=8) work tasks participated. Bilateral trapezius surface electromyographic (sEMG) activity and heart rate was recorded throughout the workday. Simultaneous inclinometer recordings from left thigh and upper arms identified periods with sitting, standing, and walking, as well as arm posture and movement. Perceived work stress and tension were recorded on visual analog scales (VAS) every hour. Trapezius sEMG activity was low in seated posture [group median 1.8 and 0.9% of activity at maximal voluntary contraction (%EMGmax) for dominant and non-dominant side] and was elevated in standing (3.0 and 2.5% EMGmax) and walking (3.9 and 3.4% EMGmax). In seated posture (mean duration 79% of workday) arm movement consistently influenced trapezius activity, accounting for approximately 20% of intra-individual variation in trapezius activity. Arm elevation was on average not associated with trapezius activity when seated; however, considerable individual variation was observed. There was no indication of increase in trapezius activity or more sustained activity pattern, nor in heart rate, in high-stress versus low-stress periods, comparing periods with seated posture for the subjects reporting contrasts of at least two VAS units in stress (n=16) or tension (n=14) score.

Noradrenaline and cortisol changes in response to low-grade cognitive stress differ in migraine and tension-type headache.

The goal of this study was to explore the relationship between indicators of sympathoneural, sympathomedullar and hypothalamic-pituitary-adrenocortical (HPA) activity and stress-induced head and shoulder-neck pain in patients with migraine or tension-type headache (TTH). We measured noradrenaline, adrenaline and cortisol levels before and after low-grade cognitive stress in 21 migraineurs, 16 TTH patients and 34 controls. The stressor lasted for 60 min and was followed by 30 min of relaxation. Migraine patients had lower noradrenaline levels in blood platelets compared to controls. Pain responses correlated negatively with noradrenaline levels, and pain recovery correlated negatively with the cortisol change in migraineurs. TTH patients maintained cortisol secretion during the cognitive stress as opposed to the normal circadian decrease seen in controls and migraineurs. There may therefore be abnormal activation of the HPA axis in patients with TTH when coping with mental stress, but no association was found between pain and cortisol. A relationship between HPA activity and stress in TTH patients has to our knowledge not been reported before. In migraine, on the other hand, both sympathoneural activation and HPA activation seem to be linked to stress-induced muscle pain and recovery from pain respectively. The present study suggests that migraineurs and TTH patients cope differently with low-grade cognitive stress.

Respiratory and stress-induced activation of low-threshold motor units in the human trapezius muscle.

The study aimed to characterize trapezius motor unit firing pattern in low-amplitude contractions, with emphasis on respiratory modulated activity. Constant-amplitude contractions with shoulder elevation, controlled by feedback of the root mean square detected surface electromyographic (SEMG) signal, typing with arm movement and tasks with mental stress were performed. Single motor unit activity was recorded by a quadrifilar fine-wire electrode. A surface electrode simultaneously recorded SEMG activity. Contraction amplitudes ranged from 1 to 10% of the SEMG signal at maximum voluntary contraction (1-10% EMG(max)). The majority ( approximately 80%) of motor units recorded during constant-amplitude contractions showed firing rate modulation at the respiratory frequency. Respiratory firing rate modulation was clear for low amplitude contractions (< 3% EMG(max)), but was reduced at higher amplitudes (3-5.9% EMG(max)). Most motor units had peak firing rate at the transition from inspiration to expiration, but peak firing rate at the transition from expiration to inspiration or at the first harmonic frequency was also observed. The SEMG signal showed little or no respiratory modulation, possibly because respiratory phase varied between motor units. Respiratory modulation of firing rates was significantly reduced in experiments with mental stress and was rarely observed in typing experiments. Both central respiratory drive and peripheral afferent input may contribute to respiratory modulation of firing rates; however, animal studies indicate a central source of the respiratory modulated input. We speculate that the reduction in respiratory modulation of motor activity with mental stress is due to activation of alternative pathways providing excitatory input to trapezius motoneurons.

The association between nocturnal trapezius muscle activity and shoulder and neck pain.

The study investigated the possible association between nocturnal trapezius muscle activity and shoulder and neck pain. Sixty female subjects participated in the study, 33 were classified as pain-afflicted on the basis of shoulder and neck pain reports for the previous 6 months. Electromyographic (EMG) activity was monitored bilaterally from the trapezius in all recordings. EMG recording of the deltoid, biceps, and hand flexors was included for 26 subjects (17 with pain) to provide a comparative basis for evaluation of the trapezius recordings. There was considerable variation in the amount of muscle activity between subjects; however, some subjects presented a continuous, low-level activity pattern throughout the presumed sleep period. Subjects classified as pain-afflicted had significantly higher activity level and longer duration of trapezius EMG activity than the pain-free subjects. The deltoid had significantly more activity than the trapezius, while the biceps and the hand flexors presented similar activity level and duration as the trapezius. Nocturnal trapezius activity was not associated with pain exacerbation the same night. We suggest nocturnal trapezius muscle activity is a pointer to physiological mechanisms that contribute to some forms of shoulder and neck pain, such as trapezius myalgia, but nocturnal muscle activity may not be casually implicated in the pain-induction process.

Daytime trapezius muscle activity and shoulder-neck pain of service workers with work stress and low biomechanical exposure.

AIM: The study aims to look for an association between trapezius muscle activity and shoulder-neck pain in work situations characterized by work stress and low biomechanical exposure. METHODS: Female subjects (n = 93) were recruited from four occupational groups: health care, shop assistants, banking, and university secretaries. Thirty-eight workers were interviewed and classified as pain-afflicted by their shoulder-neck pain score in the last 6 months; 55 were pain-free. Shoulder-neck pain, bodily state of tension and fatigue, and subjective exposure assessments were monitored by repeated hourly measurements over 24 hr. Trapezius muscle activity was recorded bilaterally by surface EMG. RESULTS: Shoulder-neck pain, perceived tension, work stress ("stressful environment"), and mental fatigue was augmented over the workday and reduced leisure time. Physical fatigue was low and stable. Thus, work stress appeared to be the dominant exposure associated with shoulder-neck pain. Muscle activity was low and similar for pain-afflicted and pain-free subjects during working hours. It was unchanged from work to leisure for the pain-afflicted workers and was significantly reduced for the pain-free group. CONCLUSIONS: Stress-induced shoulder and neck pain is not necessarily associated with elevated trapezius muscle activity, but pain-free workers may benefit from better muscle relaxation in leisure.