Ergonomic evaluation of a new truck seat design: a field study

Effects of a seat-integrated mobilization system on long-haul truck drivers motion activity, muscle stiffness and discomfort during a 4.5-h simulated driving task

OBJECTIVE

The aim of this study is to evaluate the effects of a seat-integrated mobilization system on motion activity, muscle stiffness and discomfort during prolonged driving.

METHOD

During a 4.5-h driving task, motion activity, muscle stiffness and discomfort (measured subjectively and objectively) of long-haul truck drivers were determined and compared intra-individually in a test condition with mobilization (seat-integrated stimulation) and a control condition under standardized conditions in a simulated driving study (N = 16).

RESULTS

In the experimental condition, participants showed a significantly increased motion activity and a reduced muscle stiffness compared to the control condition. Furthermore, discomfort occurred significantly more frequently in the control condition.

CONCLUSION

The mobilization system increased motion activity and reduced discomfort as well as muscle stiffness. Therefore, it provides considerable potential to counteract negative effects of prolonged sitting and to promote truck driver's health.

Musculoskeletal Disorders Associated with Occupational Driving: A Systematic Review Spanning 2006–2021

Several occupations require workers to spend long periods of time driving road vehicles. This occupational task is associated with musculoskeletal disorders. The purpose of this review was to collate, synthesize, and analyze research reporting on musculoskeletal disorders associated with occupational driving, in order to develop a volume of evidence to inform occupational disorder mitigation strategies. A systematic search of academic databases (PubMed, EBSCO host, CINAHL, SPORTDiscus, and Web of Science) was performed using key search terms. Eligible studies were critically appraised using the Joanna Briggs Institute critical appraisal checklists. A Cohen’s kappa analysis was used to determine interrater agreement between appraisers. Of the 18,254 identified studies, 25 studies were selected and appraised. The mean critical appraisal score is 69% (range 38–100%), with a fair level of agreement (k = 0.332). The studies report that musculoskeletal disorders, most commonly lower back pain, is of concern in this population, particularly in truck, bus, and taxi drivers. Risk factors for these occupations include long hours in a sitting position, years in the profession, vehicle ergonomics, and vibration.

Trunk sway changes in professional bus drivers during actual shifts on long-distance routes

Although professional bus drivers are required to perform their task while adopting a prolonged constrained sitting posture, existence of possible effects in terms of postural strategies has been scarcely investigated under actual working conditions. This study aimed to characterise modifications of trunk sway in 14 professional bus drivers during regular shifts performed on non-urban routes using a pressure-sensitive mat placed on the seat. Centre-of-pressure (COP) time series were extracted from body-seat pressure data to calculate sway parameters (i.e. sway area, COP path length, COP displacements and velocities). Results show generalised increase in trunk sway as driving progresses, which becomes statistically significant after approximately 70-100 minutes of continuous driving. This may indicate the adoption of specific strategies to cope with discomfort onset or a fatigue-induced alteration of postural features. Trunk sway monitoring of bus drivers may be useful in detecting postural behaviours potentially associated with deteriorating performance and discomfort onset. Practitioner summary: Professional bus drivers operate in sitting position for prolonged time. Such constrained posture may induce discomfort and fatigue. We investigated trunk sway during actual shifts using pressure-sensitive mats. Significant increase of sway was detected after 70 min of continuous driving. Body-seat pressure data could be used as discomfort and fatigue markers. Abbreviations: ANOVA-RM: analysis of variance with repeated measures; AP: antero-posterior; COP: center of pressure; EC: ellipse's centroid; ML: medio-lateral; SA: sway area; SP: sway path.

Short-distance versus long-distance deep-seaport container truck drivers' prevalence and perceived discomfort of musculoskeletal symptoms in the Thailand Eastern Economic Corridor

Objectives. This research aimed to study the prevalence and perceived discomfort of musculoskeletal (MSK) symptoms among short-distance and long-distance deep-seaport truck drivers. Methods. Cross-sectional analysis using a standardized modified version of the Nordic musculoskeletal questionnaire (NMQ) was carried out using direct interviews with 25 male participants: 15 short-distance and 10 long-distance truck drivers. Results. As much as 88% was reported for the existence of MSK symptoms in the past 12 months. Considering all truck groups, regardless of short or long distance, the lower back was found with the highest prevalence (72%) followed by the neck (32%). The χ² test showed long-distance truck drivers had statistically significantly more prevalence in the neck (p = 0.028) than short-distance drivers. Perceived discomfort by the Borg CR10 scale confirmed the lower back had the highest score (2.4) followed by the neck (1.44). The Kruskal-Wallis test revealed that long-distance truck drivers had significantly higher scores on the lower back and neck (p = 0.039 and p = 0.009, respectively). Conclusion. Longer exposure to prolonged non-natural working postures, vibration, traffic conditions and working stress could be the judicial causes. To minimize this problem, integrated interventions need to be implemented with particular measures among short-distance and long-distance truck drivers.

Association of Exposures to Seated Postures With Immediate Increases in Back Pain: A Systematic Review of Studies With Objectively Measured Sitting Time

OBJECTIVE

The purpose of this study was to conduct a systematic review of studies to determine whether sitting time measured objectively (by laboratory controlled time trial, direct observation, or wearable sensor) is associated with the immediate increase in low back pain (LBP) (determined by pain scale rating) in people >18 years of age.

METHODS

Four databases (PubMed, EMBASE, SPORTDiscus, and Cumulative Index to Nursing and Allied Health Literature) were searched from inception to September 1, 2018. Randomized controlled trials and cohort and cross-sectional studies, where objectively measured sitting time was temporally matched with a measure of LBP in adults, were included. Studies without a control session conducted on a separate day were excluded. Screening, full-text review, data extraction, and risk of bias assessment (Quality In Prognosis Studies) of included papers were performed independently by 2 reviewers, with a third available to resolve disagreements.

RESULTS

In total, 609 articles were identified, 361 titles/abstracts were screened,75 full-text articles were assessed for eligibility, and 10 met the inclusion criteria. All but 1 reported sitting time to be associated with an immediate increase in LBP. Six of these reported clinically relevant pain levels (n = 330). Half of the included studies were rated as having a low risk of bias and the remaining were rated as having a moderate risk of bias.

CONCLUSION

Prolonged sitting increases immediate reporting of LBP in adults; however, no conclusion between sitting and clinical episodes of LBP can be made. Based upon these findings, we recommend that future prospective studies should match objectively measured sitting with temporally related pain measurements to determine whether prolonged sitting can trigger a clinical episode of LBP.

A pre/post evaluation of fatigue, stress and vigilance amongst commercially licensed truck drivers performing a prolonged driving task

Purpose. The main purpose of this research study was to evaluate changes in fatigue, stress and vigilance amongst commercially licensed truck drivers involved in a prolonged driving task. The secondary purpose was to determine whether a new ergonomic seat could help reduce both physical and cognitive fatigue during a prolonged driving task. Two different truck seats were evaluated: an industrial standard seat and a new truck seat prototype. Methods. Twenty male truck drivers were recruited to attend two testing sessions, on two separate days, with each session randomized for seat design. During each session, participants performed two 10-min simulated driving tasks. Between simulated sessions, participants drove a long-haul truck for 90 min. Fatigue and stress were quantified using a series of questionnaires whereas vigilance was measured using a standardized computer test. Results. Seat interactions had a significant effect on fatigue patterns. Conclusion. The new ergonomic seat design holds potential in improving road safety and vehicle accidents due to fatigue-related accidents.