Mechanics of Work-related Back Pain: An Analytical Review

The prevalence of Low back pain (LBP) is exceedingly high, upwards of 80% in the general population. LBP is manifested as pain in the thoraco-lumbar area and often related to a muscle pull. This paper is a narrative review of the mechanics of work-related low back pain. In this paper, the researchers provide a different insight of the occupational low back pain as they introduce a theoretical background of the occupational low back pain and management of low back pain at workplace. In addition, the study highlight the research focus within the field of mechanical loading and biomechanical assessment methods of low back pain. The study found that low back pain is a reversible process in case causes are identified. However, it is a challenging issue to identify the causes unless well-designed models and assessment methods are applied for each case separately.

Comparison of Subjective Responses of Low Back Pain Patients and Asymptomatic Controls to Use of Spinal Exoskeleton during Simple Load Lifting Tasks: A Pilot Study

Spinal exoskeletons have been suggested as an approach for the prevention and rehabilitation of occupational low back pain (LBP). While the state-of-the-art exoskeletons were shown to substantially unload the back, user acceptance is still limited. Perceived discomfort and restriction of freedom of movement are commonly reported. In this pilot study, we explored the differences in subjective responses and user impressions to using passive spinal exoskeleton during a set of simple lifting tasks between LBP patients (n = 12) and asymptomatic individuals (n = 10). Visual analog scales (0–10) were used for all assessments. Overall, the results showed mostly similar responses or slightly more positive responses to the exoskeleton from LBP patients. Most notably, the LBP patients reported a statistically significant (p = 0.048) higher willingness to use the device daily (5.36 ± 4.05) compared to the control group (2.00 ± 1.85) and also gave the device a higher overall grade (6.58 ± 1.98 vs. 4.30 ± 2.26; p = 0.021). This study has demonstrated that individuals with current LBP responded more favorably to the use of the spinal exoskeleton for simple lifting tasks. This implies that current exoskeletons could be appropriate for LBP rehabilitation, but not preventions, as pain-free individuals are less willing to use such devices. Future studies should explore whether different exoskeleton designs could be more appropriate for people with no LBP issues.

The Risk Assessment of Low Back Pain Based on Allowable Weight Limits for Manual Lifting in Iranian Women Workers

Background: Manual load lifting is one of the most important risk factors for musculoskeletal disorders, including occupational low back pain. These disorders are common in women workers who perform manual load lifting and displacement tasks at the workplace. Objectives: To determine the level of musculoskeletal disorders and to evaluate the recommended limits of manual load lifting in women workers using WISHA checklist and ACGIH TLV, the recommended limits of Iran, and compare the results of two methods. Methods: This cross-sectional study was conducted on 100 women workers who performed manual loading tasks in 2018. Nordic questionnaire was used to determine the prevalence of musculoskeletal disorders, and two methods, WISHA checklist and ACGIH TLV, were used to determine the recommended allowable limits for manual load lifting. Results: The results of the prevalence assessment of musculoskeletal disorders showed that most of the musculoskeletal disorders were in the low back (55%) in the past 12 months. The results of the assessment of the allowable lifting limits also showed that 8% of women in the WISHA checklist method and 31% in the ACGIH TLV method were at risk for low back injuries. The kappa coefficient test (0.031) also showed that there is a poor and insignificant agreement between the two methods of WISHA checklist and ACGIH TLV in determining the allowable limits for manual lifting. Conclusions: The results of this study showed a poor agreement between the WISHA checklist and ACGIH TLV in determining the allowable limits for manual lifting, which suggest that the two methods are not mutually exclusive. Hence, owing to the increasing presence of women in various occupations and raising the hand load-lifting and, naturally increasing occupational low back pain among them, it is necessary that in a comprehensive study, the allowable limits of lifting loads according to anthropometric and physiological characteristics of Iranian women, prepare and compile according to a comprehensive instruction.