Because of population aging, the consensus among policy makers is that employment in older workers must increase. However, methods for attaining this are uncertain. Blended work, which consists of working anywhere and any-time with information and communication technology, may help achieve this goal. The article focuses on 4 top-ics related to older workers and blended work: the benefits, risks, individual- and organizational-level barriers, and organizational and government interventions and policies designed to remove these risks and barriers. Legislation to protect against age discrimination and disability associated with age is also reviewed. The objectives are to dis-cuss the literature on blended work and the older worker and highlight some consequences the Age Discrimination in Employment Act and American with Disabilities Act may have on blended work. Delaying retirement through blended work could promote older workers’ health and well-being, but risks and barriers at individual- and organi-zational-levels are not inconsequential. At the individual level, these include social isolation, and managements’ loss of control over employees at the organizational level. Potential interventions include developing blended work as an employee benefit to replace long distance travel. Federal policies include providing subsidies to state and local gov-ernments to reduce costs of upgrading broadband fiber-optic cables. Specific subgroups of workers are more likely to benefit from blended work. Older white collar professionals with good technological and computer skills and who can work independently are one subgroup that might fit a blended worker personality.

Objective:  This study systematically summarizes biochemical biomarker research in non-traumatic musculoskeletal disorders (MSDs).  Two research questions guided the review:  1) Are there biochemical markers associated with neck and upper extremity MSDs? and, 2) Are there biochemical markers associated with the severity of neck and upper extremity MSDs? 

Methods:  A literature search was conducted in PubMed and SCOPUS.  Eighty-seven studies met primary inclusion criteria.  Following a quality screen, data were extracted from 44 sufficient quality articles.

Results:  Most of the 87 studies were cross-sectional and utilized convenience samples of patients as both cases and controls.  A response rate was explicitly stated in only 11 (13%) studies.  Less than half of the studies controlled for potential confounding through restriction or in the analysis.  Most sufficient quality studies were conducted in older populations (mean age in one or more analysis group > 50 yrs).

In sufficient quality articles, 82% demonstrated at least one statistically significant association between the MSD(s) and biomarker(s) studied.  Evidence suggested that: a) the collagen repair marker TIMP-1 is decreased in fibroproliferative disorders, b) 5-HT (serotonin) is increased in trapezius myalgia, and c) triglycerides are increased in a variety of MSDs.  Only five studies showed an association between a biochemical marker and MSD severity.

Conclusion: While some MSD biomarkers were identified, limitations in the articles examined included possible selection bias, confounding, spectrum effect (potentially heterogeneous biomarker associations in populations according to symptom severity or duration) and insufficient attention to co-morbid conditions. A list of recommendations for future studies is provided.

Purpose: Approximately 25-30% of nursing personnel experience knee pain (KP). We sought to identify physical and psychosocial work exposures, and personal factors related to prevalent, incident, and persistent KP 5-8 years after safe resident handing program (SRHP) implementation in nursing homes.

Methods: Health and exposure information was obtained from worker surveys 5-6 years (“F5”) and 7-8 years (“F6”) post-SRHP implementation. Prevalent KP correlates were examined at F5; persistent and incident KP predictors were analyzed at F6, utilizing robust Poisson multivariable regression.

Results: F5 KP prevalence (19.7%) was associated with combined physical exposures, and with either high job strain or low social support, in separate models. Two-year persistent KP was similarly associated with these psychosocial exposures. Being overweight was associated with KP in all analyses.

Conclusions: The SRHP program did not eliminate knee physical loading, which should be reduced to prevent nursing home worker KP. Workplace psychosocial exposures (high job strain, low social support) also appeared germane.

Background. Relative blood volume (RBV) and muscle oxygenation (TSI) can be measured using near infrared spectroscopy (NIRS), but no studies have used NIRS with workers performing their job in the field. The study aims were (1) to assess day-to-day within-subjects dispersion in NIRS measurements during work, and (2) to determine whether trapezius RBV and TSI differed between office and industrial workers. Electromyography (EMG) measured trapezius muscle activity.

Methods. Portable NIRS and EMG instruments were adhered to the trapezius of healthy female industrial (n = 8) and office (n = 10) workers for approximately four hours on two separate days. Mean and standard deviation (SD) RBV, TSI and 50th percentile EMG were calculated for both days separately. Participants were videotaped to demarcate work and rest periods, and to qualitatively assess ergonomic exposures. Two-way mixed effects models were constructed to examine outcomes, with occupation (office/industrial) and work/rest as fixed effects and subject as a random effect.

Results. Industrial workers appeared to have more variable arm postures and handled heavier loads than office workers. The between-days variability of RBV and TSI indicated that NIRS performed well in an occupational setting. Median trapezius EMG showed an effect of occupation (p < 0.0001), and an interaction between occupation and work/rest (p < 0.0001). As expected, industrial workers had higher median EMG overall and during work, but office workers had a higher EMG during rest. Similar results for EMG SD were found. Mean RBV and RBV SD were greater in industrial workers. No effects on mean TSI were found. However, TSI SD was higher in industrial workers, while TSI SD was greater in office workers during rest.

Discussion. NIRS had a satisfying reliability and showed face validity with respect to expected responses to occupational work. NIRS shows promise as a method for measuring hemodynamics in the field.

Background

This study systematically summarizes quantitative imaging biomarker research in non-traumatic neck and shoulder musculoskeletal disorders (MSDs). There were two research questions: 1) Are there quantitative imaging biomarkers associated with the presence of neck and shoulder MSDs?, 2) Are there quantitative imaging biomarkers associated with the severity of neck and shoulder MSDs?

Methods

PubMed and SCOPUS were used for the literature search. One hundred and twenty-five studies met primary inclusion criteria. Data were extracted from 49 sufficient quality studies.

Results

Most of the 125 studies were cross-sectional and utilized convenience samples of patients as both cases and controls. Only half controlled for potential confounders via exclusion or in the analysis. Approximately one-third reported response rates. In sufficient quality articles, 82% demonstrated at least one statistically significant association between the MSD(s) and biomarker(s) studied. The literature synthesis suggested that neck muscle size may be decreased in neck pain, and trapezius myalgia and neck/shoulder pain may be associated with reduced vascularity in the trapezius and reduced trapezius oxygen saturation at rest and in response to upper extremity tasks. Reduced vascularity in the supraspinatus tendon may also be a feature in rotator cuff tears. Five of eight studies showed an association between a quantitative imaging marker and MSD severity.

Conclusions

Although research on quantitative imaging biomarkers is still in a nascent stage, some MSD biomarkers were identified. There are limitations in the articles examined, including possible selection bias and inattention to potentially confounding factors. Recommendations for future studies are provided.

Background. Although the potential for musculoskeletal disorder (MSD) biomarkers to detect subclinical disease and monitor MSD severity was discussed more than 20 years ago, only one review on biochemical biomarkers exclusive to humans has been published (Saxton 2000). The aim of this study was to systematically summarize biochemical biomarker research in neck and upper extremity MSDs that could appear in a work-related context. Two research questions guided the review: (1) Are there biochemical markers associated with neck and upper extremity MSDs? (2) Are there biochemical markers associated with the severity of neck and upper extremity MSDs?

Methods: A literature search was conducted in PubMed and SCOPUS. 87 studies met primary inclusion criteria. Following a quality screen, data were extracted from 44 sufficient-quality articles.

Results. Most of the 87 studies were cross-sectional and utilized convenience samples of patients as both cases and controls. A response rate was explicitly stated in only 11 (13%) studies. Less than half of the studies controlled for potential confounding through restriction or in the analysis. Most sufficient-quality studies were conducted in older populations (mean age in one or more analysis group > 50 yrs). In sufficient-quality articles, 82% demonstrated at least one statistically significant association between the MSD(s) and biomarker(s) studied. Evidence suggested that: (a) the collagen repair marker TIMP-1 is decreased in fibroproliferative disorders, (b) 5-HT (serotonin) is increased in trapezius myalgia, and (c) triglycerides are increased in a variety of MSDs. Only five studies showed an association between a biochemical marker and MSD severity.

Discussion. While some MSD biomarkers were identified, limitations in the articles examined included possible selection bias, confounding, spectrum effect (potentially heterogeneous biomarker associations in populations according to symptom severity or duration) and insufficient attention to co-morbid conditions. A list of recommendations for future studies is provided.

Purposes

Mobile devices with various screen sizes are now popular.  Screen size may affect how persons choose to interact when typing with such devices.  Self-reported duration and frequency of text messaging has been associated with musculoskeletal disorder (MSD) symptoms, particularly in the shoulder, neck, and thumb (1, 2).  It is unknown which aspects of mobile device usage may increase MSD risk.  However, non-neutral neck and wrist postures are associated with MSDs in office workers engaging in keyboarding (3-8).  The study aim was to determine if mobile device screen size affects neck and/or wrist posture during self-determined texting positions.  Also, fingers used in texting were tabulated by screen size, as this may affect MSD risk.

Methods

Three touch screen mobile devices of different screen sizes – 3.5” (Apple iPod Touch MC544LL), 7” (Samsung Galaxy Tab GT-P1010) and 9.5” (Apple iPad 2) -- were randomly presented to asymptomatic college students (n = 20).  Each device was made ready for simulated texting by activating the “Notes” or a similar application.  Devices were placed screen down on a table 1 m away from the participant.  Participants retrieved the device, resumed sitting in a chair, and spent as much time as desired to determine how they wanted to text “hi how are you” repeatedly for 10 seconds.  Wrist and neck postures were measured through electrogoniometry and sagittal plane motion analysis, respectively.  Fingers used to text and whether the device was placed on the lap were noted.  Excel (Microsoft Corp., Redmond, WA) and SAS V9.3 (SAS Institute Inc., Cary, NC) were used in data analysis.  Outcome variable trends by screen size were determined using SAS PROC GLM for repeated measures, with p < 0.05 denoting statistical significance.

Results

Ninety percent of subjects using the 3.5” screen chose to text with both thumbs (table).  As screen size increased, more used the right index finger as more varied texting styles were chosen.  Additionally, more placed the entire device or its bottom edge on their lap.  Wrist extension and ulnar deviation, and cervical flexion increased with increasing screen size (test for trend, all p < 0.01, table).

Conclusions

Greater prevalence of non-neutral neck and wrist postures were found during texting with increasing touch screen size.  These factors may increase MSD risk.  However, decreased thumb usage occurs with greater screen size.  Such larger screens may be protective against thumb symptoms.  Further studies are warranted.

Objective: We aimed to determine if serum biochemical and MRI biomarkers differed between high volume (≥ 230 texts sent/day; n = 5) and low volume (≤ 25 texts sent/day; n = 5) texters.  A secondary aim was to ascertain what correlations between the biochemical and imaging biomarkers could tell us about the pathophysiology of early onset tendinopathies.

Background: Text messaging has become widespread, particularly among college-aged young adults.  There is concern that high rates of texting may result in musculoskeletal disorders, including tendinopathies.  Pathophysiology of tendinopathies is largely unknown.

Method: Ten females with a mean age of 20 were recruited. We examined serum for 20 biomarkers of inflammation, tissue degeneration and repair. We used conventional MRI and MRI mean intratendinous signal intensity (MISI) to assess thumb tendons.  Correlations between MISI and serum biomarkers were also examined.

Results: Three high volume texters had MRI tendinopathy findings as did one low volume texter.  Increased serum TNF-R1 was found in high volume texters compared to low volume texters, as were non-significant increases in MISI in two thumb tendons.  Serum TNF-R1 and TNF-α correlated with MISI in these tendons, as did IL1-R1. 

Conclusion: These results suggest that early onset tendinopathy with concurrent inflammation may be occurring in prolific texters. Further studies with larger sample sizes are needed for confirmation.

Text messaging has become widespread, particularly among college-aged young adults.There is concern that high rates of texting may result in musculoskeletal disorders, including tendinopathies. We examined serum biomarkers, conventional MRI findings, and MRI mean intratendinous signal-to-noise ratio (MISI) of thumb tendons to determine if high volume texters (≥ 230 texts sent/day; n = 5) would be more likely than low volume texters (≤ 25 texts sent/day; n = 5) to have early onset tendinopathy and inflammation. Three of the high volume texters had MRI findings of tendinopathy as did one low volume texter. Increased serum TNF-R1 was found in high volume texters compared to low volume texters of college age, as were non-significant increases in MISI in 2 thumb tendons. Serum TNF-R1 and TNF-α correlated with the MISI in these tendons, as did IL1-R1. These results suggest that early onset tendinopathy with concurrent inflammation may be occurring in prolific texters. Further studies with larger sample sizes are needed to confirm these findings.

Objectives. Healthcare workers have high rates of low back pain (LBP) related to handling patients. A large chain of nursing homes experienced reduced biomechanical load, compensation claims and costs following implementation of a safe resident handling programme (SRHP). The aim of this study was to examine whether LBP similarly declined and whether it was associated with relevant self-reported occupational exposures or personal health factors.

Methods. Worker surveys were conducted on multiple occasions beginning with the week of first SRHP introduction (baseline). In each survey, the outcome was LBP during the prior 3 months with at least mild severity during the past week. Robust Poisson multivariable regression models were constructed to examine correlates of LBP cross-sectionally at 2 years (F3) and longitudinally at 5–6 years (F5) post-SRHP implementation among workers also in at least one prior survey.

Results. LBP prevalence declined minimally between baseline and F3. The prevalence was 37% at F3 and cumulative incidence to F5 was 22%. LBP prevalence at F3 was positively associated with combined physical exposures, psychological job demands and prior back injury, while frequent lift device usage and ‘intense’ aerobic exercise frequency were protective. At F5, the multivariable model included frequent lift usage at F3 (relative risk (RR) 0.39 (0.18 to 0.84)) and F5 work– family imbalance (RR=1.82 (1.12 to 2.98)).

Conclusions. In this observational study, resident lifting device usage predicted reduced LBP in nursing home workers. Other physical and psychosocial demands of nursing home work also contributed, while frequent intense aerobic exercise appeared to reduce LBP risk.

Background

Texting is associated with adverse health effects including musculoskeletal disorders, sleep disturbances, and traffic crashes. Many studies have relied on self-reported texting frequency, yet the validity of self-reports is unknown. Our objective was to provide some of the first data on the validity of self-reported texting frequency, cell phone characteristics including input device (e.g. touchscreen), key configuration (e.g., QWERTY), and texting styles including phone orientation (e.g., horizontal) and hands holding the phone while texting.

Methods

Data were collected using a self-administered questionnaire and observation of a texting task among college students ages 18 to 24. To gauge agreement between self-reported and phone bill-derived categorical number of daily text messages sent, we calculated percent of agreement, Spearman correlation coefficient, and a linear weighted kappa statistic. For agreement between self-reported and observed cell phone characteristics and texting styles we calculated percentages of agreement. We used chi-square tests to detect significant differences (α = 0.05) by gender and study protocol.

Results

There were 106 participants; 87 of which had complete data for texting frequency analyses. Among these 87, there was 26% (95% CI: 21–31) agreement between self-reported and phone bill-derived number of daily text messages sent with a Spearman’s rho of 0.48 and a weighted kappa of 0.17 (95% CI: 0.06-0.27). Among those who did not accurately report the number of daily texts sent, 81% overestimated this number. Among the full sample (n = 106), there was high agreement between self-reported and observed texting input device (96%, 95% CI: 91–99), key configuration (89%, 95% CI: 81–94), and phone orientation while texting (93%, 95% CI: 86–97). No differences were found by gender or study protocol among any items.

Conclusions

While young adults correctly reported their cell phone’s characteristics and phone orientation while texting, most incorrectly estimated the number of daily text messages they sent. This suggests that while self-reported texting frequency may be useful for studies where relative ordering is adequate, it should not be used in epidemiologic studies to identify a risk threshold. For these studies, it is recommended that a less biased measure, such as a cell phone bill, be utilized.

Purposes

Self-reported duration and frequency of text messaging has been associated with musculoskeletal disorders (1, 2).  The only published study examining self-reported texting validity is among young adolescents (3).  Overestimation in lower volume and underestimation in higher volume texters occurred as compared with service provider information.  The corresponding validity in college students is unknown.  The current objective was to determine the validity of self-reported categorical number of daily texts sent.  Much as office workers have been found to overestimate their computer keyboard usage (4-6), it was hypothesized that texters would overestimate daily texts sent.  Since phone characteristics (e.g., keyboard type and phone orientation), and texting styles (number of hands holding phone, fingers used to text) may affect the risk of musculoskeletal disorders, we also assessed their self-reported validity.

Methods

College students (n = 108) filled out a questionnaire noting daily texts sent, phone characteristics, and texting styles.  Their phone bill was used for verification of daily texts sent, and they were observed texting a short message to verify phone characteristics and texting styles.  A linear weighted kappa statistic was used to gauge the agreement between categorical self-reported and phone-bill derived daily text messages sent.  Percentages of agreement were presented to ascertain concordance between self-reported and observed cell phone characteristics and texting styles.  Gender was examined as a potential confounder.

Results

Subjects overestimated their daily texts sent in all phone-bill verified texting volumes. The weighted kappa statistic was 0.18 (95% CI: 0.07-0.30) with 43.8% agreement.  There was little difference in recall by gender. 

High agreement (> 92%) was achieved between self-reported and observed input device, phone manufacturer, and phone orientation when texting (figure).  However, there was low agreement between self-reported and observed texting styles.  There was little difference in validity by gender.

Conclusions

College students consistently overestimated the number of daily texts sent.  This occurred in all frequencies of text messaging, suggesting that risk underestimation will occur in epidemiology studies where self-reported texting is an exposure variable.  Hence, any such studies should rely on a more valid measure, i.e., a phone bill.  Validity of self-reported texting style was low.  However, texting style as observed during a short trial executed under experimental conditions may not be reflective of the more diverse texting style(s) that would be observed during extended periods and in real-world settings for the students.  Further research is needed to confirm the study findings in other age groups.

The study aim was to determine the effects of input device type, texting style, and screen size on upper extremity muscle activity and neck and wrist posture during a short texting task in college students. Users of a physical keypad produced greater thumb and wrist extensor muscle force than when texting with a touch screen; using a touch screen required greater wrist extension. Texting on either device produced greater finger flexor and wrist extensor muscle force and greater radial deviation when 1 hand/thumb was used, compared to both hands/thumbs. As touch screen size increased, more participants held the device on their lap, and there was a trend for greater muscle force in finger flexors, wrist extensors, and trapezius, and greater wrist extension, ulnar deviation, and cervical spine flexion. Future research can help inform whether the ergonomic stressors observed during texting are associated with the risk of musculoskeletal disorders.