Grant D. Huang

Development of a screen for predicting clinical outcomes in patients with work-related upper extremity disorders.

This study prospectively examined the extent to which a set of medical, physical, ergonomic, occupational psychosocial, and individual psychosocial variables would predict clinical outcome associated with a diverse set of work-related upper extremity disorders in recently diagnosed individuals. This investigation was designed to develop a tool for use in a clinical setting to assist in identifying patients at risk for poorer outcome. Outcome was measured at 1, 3, and 12 months after completing a baseline questionnaire. Outcome status was based on a median split of a standardized composite index (symptoms, function, workdays lost, and mental health). Logistic regression indicated that predictors of poorer outcome at 1 month were: upper extremity comorbidity (risk ratio [RR], 1.58), pain severity (RR, 1.45), ergonomic risk exposure (RR, 1.07), low job support (RR, 1.03), and pain coping style (RR, 1.54). At 3 months, poorer outcome was predicted by: symptom severity (RR, 10.46), job stress (RR, 1.20), and pain coping style (RR, 1.98). The number of prior treatments/providers (RR, 1.77), past recommendation for surgery (RR, 6.43), and pain coping style were found to predict poorer outcome at 12 months. Sensitivity and specificity, respectively, for the models were 77.4% and 71.8% at 1 month, 80.6% and 82.4% at 3 months, and 80.6% and 83.3% at 12 months. The results indicate that baseline measures of ergonomic and psychosocial stress, pain severity, and pain coping style predict clinical outcome at shorter intervals, whereas number of past treatments/providers, recommendation for surgery and pain coping style predict longer-term outcome. The resulting prognostic screen provides a simple tool that assesses the multidimensional nature of work-related upper extremity disorders and predicts clinical outcome. Furthermore, the findings suggest the importance of early intervention that addresses both physical and psychosocial stressors at work. Specific recommendations to reduce the impact of observed risk factors are discussed.

Job stress, upper extremity pain and functional limitations in symptomatic computer users.

BACKGROUND Research suggests that exposure to occupational stressors are related to the presence and/or exacerbation of work-related upper extremity symptoms in office workers. Also workers response to work demands and/or job stressors (i.e., workstyle) may exacerbate symptom severity and impact function. The present study examines the association among work demands, job stress and workstyle on pain and function. METHODS 124 symptomatic female office workers completed a questionnaire measuring demographics, medical history, work demands, perception of the work environment, workstyle, pain intensity, functional impact, and time lost from work. RESULTS Heightened job stress and the tendency to continue to work in a way that contributes to pain to ensure high quality (dimension of workstyle) were related to pain intensity at work and decreased function. These variables, in addition to hours worked per year, were related to increased pain experienced across the work week. The model tested did not predict the occurrence of lost time. CONCLUSIONS The present findings provide support for the association between job stress, workstyle, upper extremity pain and function. While it is not possible to determine the exact direction of the observed relationships, these results are consistent with prior research indicating the potential significance of job stress and workstyle on symptom exacerbation and functional limitations. Implications for evaluation and intervention are discussed.

Predictors of occupational low back disability: implications for secondary prevention.

Over the past decade, studies have identified a combination of demographic, physical/medical, ergonomic, and psychosocial factors in the development of work disability related to occupational low back pain. Using such data on disability risk factors, investigators have begun to develop risk identification and disability prevention programs. As part of an ongoing effort to develop a secondary prevention program, the present case-control study identified the relative contribution of demographic, physical demand, physical fitness, as well as occupational and individual psychosocial variables to back-related work disability in the US Army. Soldiers (n = 174) diagnosed with a lumbosacral strain and medically discharged from the Army were compared with non-disabled controls (n = 173). Dependent measures were obtained from the US Army Health Risk Appraisal (HRA). For cases, these data pre-dated disability determination by 1 to 3 years. For controls, the HRA was completed during the same time period. Significant predictors of low back disability were: age (odds ratio [OR] = 1.13 per year), lower rank (E2/E3) (OR = 4.08/OR = 3.02), infrequent aerobic exercise (OR = 2.2), higher work stress (OR = 2.71), worries (OR = 2.17), and lower social support (OR = 5.07). The model correctly classified 73.13% of all subjects. These results highlight the importance of considering age, status level in the organization, frequency of aerobic exercise, occupational stress, general worries, and social support for the early detection of soldiers at increased risk for back-related disability. Additionally, the findings support past research indicating the multivariate nature of work disability and emphasize the importance of considering such factors in future secondary prevention efforts.

Workstyle: development of a measure of response to work in those with upper extremity pain.

Workstyle or the behavioral, cognitive, and physiological response that can occur in some individuals to increases in work demands has been proposed to help explain the link between ergonomic and psychosocial factors in the exacerbation of work-related upper extremity symptoms. Currently, there is no measure of this construct, hindering research on its potential link to work related upper extremity problems in the workplace. The present study describes the development and psychometric properties of a measure of workstyle. Questionnaire items reflecting dimensions of workstyle as per the original conceptualization were generated primarily through focus groups with office workers and separate groups held with occupational physicians, physical therapists, occupational health psychologists, and experts in ergonomics, behavioral science, and human factors. Items created through this process were then administered to 282 symptomatic and asymptomatic office workers. Measures of job stress, ergonomic risk, upper extremity symptoms, and functional limitations were also obtained. The workstyle questionnaire was divided into two broad dimensions: Characteristic responses to work and Response to increased work demands. The scale development process as indicated by factor analysis yielded subscales that are theoretically consistent with the workstyle construct. These subscales include: working through pain, social reactivity at work, limited workplace support, deadlines/pressure, self imposed work pace/workload, breaks, mood, pain/tension, autonomic response, and numbness tingling. The internal consistency of these subscales varied from 0.61 to 0.91, n = 282 while the test–retest (3 weeks) reliability for the various subscales ranged from r = 0.68 to 0.89, n = 143. A total workstyle score was computed that excluded the pain/tension and numbness/tingling subscales to avoid circular reasoning in terms of the measure’s relationship to outcomes of pain and functional limitations. The total score was stable over time and provided unique variance in relation to traditional measures of job stress. Total workstyle score was significantly associated with higher levels of pain, and greater functional limitations. Dimensions of the workstyle construct were identified. The workstyle measure possesses acceptable psychometric properties in office workers who work with computers. This measure can be used in future studies on the interaction of psychosocial and ergonomic factors in the exacerbation of upper extremity pain and functional limitation.

Measurement properties of a self-report index of ergonomic exposures for use in an office work environment.

Office work-related upper extremity symptoms and disorders have been associated with static work posture, repetition, and inadequate recovery in the anatomic structures of the neck and upper extremities. Despite these associations, relatively little research has been conducted on the development of practical measures of these ergonomic exposures. The present study examines the measurement properties of an upper-extremity–specific self-report index of ergonomic exposures. Ninety-two symptomatic office workers completed a Web-based questionnaire measuring demographic variables, ergonomic exposures, pain, job stress, and functional limitations. Comparisons of internal consistency, construct validity, and discriminative and predictive abilities were made between the self-report index and an observational exposure assessment checklist. Results indicated that the self-report index had acceptable measurement properties. Furthermore, higher levels of self-reported ergonomic exposures were associated with upper extremity pain, symptom severity, and functional limitations. In contrast, higher levels of observed exposure were related only to lower levels of general physical function. The self-report measure has potential for use in occupational health surveillance programs for office work environments and as an outcome measure of ergonomic exposure in intervention trials. These results also suggest the need for using multiple methods when assessing ergonomic exposures.

Integrated case management for work-related upper-extremity disorders: impact of patient satisfaction on health and work status.

Compare the effects of integrated case management and usual care on patient satisfaction in employees with work-related upper extremity disorder (WRUED), and consider the implications of higher levels of satisfaction.Describe those patient-related and work-related factors that predict the severity of upper limb symptoms and the degree of functional limitation 6 and 12 months after intervention.Enumerate the factors influencing the interval before return to work in employees with WRUED who are managed by traditional or integrated case management. An integrated case management (ICM) approach (ergonomic and problem-solving intervention) to work-related upper-extremity disorders was examined in relation to patient satisfaction, future symptom severity, function, and return to work (RTW). Federal workers with work-related upper-extremity disorder workers’ compensation claims (n = 205) were randomly assigned to usual care or ICM intervention. Patient satisfaction was assessed after the 4-month intervention period. Questionnaires on clinical outcomes and ergonomic exposure were administered at baseline and at 6- and 12-months postintervention. Time from intervention to RTW was obtained from an administrative database. ICM group assignment was significantly associated with greater patient satisfaction. Regression analyses found higher patient satisfaction levels predicted decreased symptom severity and functional limitations at 6 months and a shorter RTW. At 12 months, predictors of positive outcomes included male gender, lower distress, lower levels of reported ergonomic exposure, and receipt of ICM. Findings highlight the utility of targeting workplace ergonomic and problem solving skills.

Identifying Work Organization Targets for a Work-Related Musculoskeletal Symptom Prevention Program

While research linking work organization factors to work-related musculoskeletal disorders has been increasing, there is still a need to delineate specific dimensions to be targeted by intervention programs. The present cross-sectional investigation identified work organization risk factors for low back (LB) and upper extremity (UE) symptoms and determined the magnitudes of such associations. Questionnaires containing items on ergonomic, individual psychosocial, and occupational psychosocial factors were administered to a sample of workers (n = 248 U.S. Marines) in previously identified high-risk job categories for musculoskeletal disorders. Study participants were categorized into groups of either having LB symptoms only, UE symptoms only, concurrent LB and UE symptoms, or being asymptomatic on the basis of self-report. Additionally, measures of pain intensity, physical function, and mental health were obtained. Linear regression analyses adjusting for demographics, ergonomic factors, and individual psychosocial factors indicated that decision authority and experienced responsibility for work were significant correlates for pain intensity during the week. Logistic regression analyses indicated that ergonomic stressors were a risk factor for all symptomatic groups (OR = 1.02 per point increase; 95% CI: 1.0–1.1). Time pressure (OR = 1.2 per point increase; 95% CI: 1.0–1.4) was also a significant risk factor for all symptomatic groups, while cognitive processing placed workers at higher risks for concurrent LB and UE symptoms (OR = 1.2; 95% CI: 1.0–1.4). Interpersonal demands placed individuals at a lower risk for LB symptoms (OR = 0.8; 95% CI: 0.5–1.0). Findings highlight the importance of intervention approaches that address time pressure, cognitive processing factors, and interpersonal demands at work. In light of past biobehavioral studies, these results also suggest that job redesign and interventions that address a workers workstyle when faced with increased work demands may help reduce the likelihood of musculoskeletal symptoms and/or their intensity.

Self-Report Measure of Low Back-Related Biomechanical Exposures: Clinical Validation

Low back pain and symptoms are major contributors to ambulatory visits, economic burden, and reduced readiness among military personnel and employers in the civilian workplace as well. While a link between low back pain and biomechanical exposures has been established, efficient surveillance methods of such exposures are still needed. Furthermore, the utility of self-report measures for biomechanical exposures has not been examined extensively. The present cross-sectional study analyzed questionnaire data from US Army soldiers (n = 279) working in previously identified occupational specialties that were associated with high risk for low back pain and/or low back pain disability. Demographic characteristics, physical workload, health behaviors, and psychosocial factors were assessed in addition to self-reported workplace biomechanical exposures using the Job Related Physical Demands (JRPDs). Outcomes included self-reported low back pain severity, low back symptoms, functional limitations, and general physical health. The results indicated that the self-report measure of biomechanical exposure had a high degree of internal consistency (Cronbach alpha, 0.95). The JRPD index correlated with low back symptoms, pain intensity, function, and perceived work load using the Borg scale. Regression analyses indicated statistically significant associations between the JRPD and back pain specific pain severity and physical function, but not for general physical health (SF-12) after controlling for age, gender, educational level, job type, and reported exercise and work stress. Specifically, higher JRPD scores (representing greater biomechanical exposure) were associated with higher levels of pain intensity and functional limitations. Higher JRPD scores were found to place an individual at a greater likelihood for being a case with low back pain within the past 12 months (OR = 1.01 per point increase in scale-95%; range 38–152; CI = 1.00–1.02, p ≤ 0.05). While future longitudinal studies of the JRPD determining the predictive validity of the measure are needed, the present study provides evidence of the utility of the JRPD for assessing biomechanical exposures associated with low back pain within high-risk jobs. The findings suggest that the JRPD may assist with surveillance efforts and be useful as a process and/or outcome measure in research related to occupational rehabilitation.

Americans with Disabilities Act Litigation and Musculoskeletal-Related Impairments: Implications for Work Re-Entry

The Americans with Disabilities Act (ADA) was designed, in part, to assist in work re-entry for the disabled. ADA-related complaints that are more difficult to resolve and consequently reach the litigation stage may provide useful insights into the challenges associated with the re-integration of disabled workers into the workplace. The present study identified patterns of impairments and areas of dispute from all ADA litigation (n = 189) between 1990 to 1996. While HIV/AIDS was the most common single impairment category (18.8%), combined musculoskeletal-related (i.e., back and upper extremity) impairments comprised the largest group of impairments (23.4% of total) involved in litigation. The top two areas of dispute were termination and alleged failure to provide reasonable accommodation, respectively. The distribution of musculoskeletaland nonmusculoskeletal-related cases were similar for these two areas of dispute. These findings highlight the direction upon which effective work re-entry strategies for workers with musculoskeletal-related disabilities must focus. Efforts to provide effective accommodation for these workers should improve retum-to-work outcomes and reduce the risk of litigation. Specific recommendations for such efforts are provided.