Whole-body vibration: is there a causal relationship to specific imaging findings of the spine?

Vibratory Impact of 3 Different Ambulance Suspension Systems on the Simulated Neonate and Health Care Provider During Normal Driving Conditions

OBJECTIVE

Patients and health care providers experience varying degrees of vibration during interfacility ground transport. The impact of vibration on term and preterm neonates may result in physiologic instability and increased risk of intracranial hemorrhage, whereas the impact on health care providers has been shown to include an increase in perceived and physiologic stress levels and may contribute to chronic back and neck pain. This study aimed to evaluate 3 common ambulance suspension systems and the corresponding vibratory impact produced during typical interfacility driving conditions on adult caregiver and neonatal patient mannequins.

METHODS

Type 3 ambulances with air, liquid, and traditional suspensions were evaluated using various driving tests to simulate typical road conditions. Vibrations were measured using triaxial accelerometers placed on the chassis, upon the head of a seated caregiver mannequin in the ambulance bench seat, and the head of a neonatal mannequin supine and secured in an isolette. Data analysis included the average vibration frequency, root mean square values, and maximum vibration amplitudes.

RESULTS

The results showed that the supine neonatal mannequin experienced the highest vibration frequency and amplitude in the vertical (x) direction, whereas the adult caregiver mannequin experienced higher vibration frequencies in both parallel (y) and lateral (z) directions and the highest vibration amplitude in the y direction. The liquid suspension system consistently demonstrated the lowest vibration levels in all driving conditions and directions, whereas traditional suspension had the highest values.

CONCLUSION

This study provides important insights into the vibrations incurred by simulated neonatal patients and health care providers during ambulance transport. The directional vibration frequency and amplitude differ between a neonatal mannequin and an adult mannequin when placed in typical positions with typical restraints during varied ambulance driving conditions. In all directional movements and driving conditions, a liquid suspension system decreases vibration frequency and amplitude more than air or traditional systems. The live patient and caregiver impact of these results should be further investigated.

The association between whole body vibration exposure and spine degeneration on imaging: A systematic review

BACKGROUND

Low frequency vibrations from motorized vehicles and heavy equipment have been associated with musculoskeletal disorders. Spine degeneration on diagnostic imaging provides direct and objective measures of the possible effects of such exposures on the spine.

OBJECTIVE

The objective of this systematic review was to evaluate the association of exposure to whole-body vibration (WBV) with spine degeneration on imaging.

METHODS

We conducted electronic searches in MEDLINE, CINAHL, EMBASE, and Web of Science to July 2021. Two reviewers independently screened search results, assessed quality, and extracted data. Studies evaluating the exposure to WBV and lumbar spine degeneration on imaging were included.

RESULTS

Fifteen studies (16 manuscripts) were included. Seven studies including a meta-demonstrated moderate quality evidence of no association between WBV and disc degeneration. There was also moderate quality evidence of no association between WBV and disc height narrowing and osteophytes. Overall, there was low level evidence of no association between WBV and other degenerations findings.

CONCLUSIONS

There was moderate to low quality evidence suggesting no association between WBV exposures with spine degeneration on imaging. The results of this study currently do not support assertion that motorized vehicle and WBV exposure accelerates degeneration and causes structural damage to the spine.

The association between occupational loading and spine degeneration on imaging - a systematic review and meta-analysis

Background

There are inconsistencies in findings regarding the relationship of occupational loading with spinal degeneration or structural damage. Thus, a systematic review was conducted to determine the current state of knowledge on the association of occupational loading and spine degeneration on imaging.

Methods

We performed electronic searches on MEDLINE, CINAHL and EMBASE. We included cross-sectional, case control and cohort studies evaluating occupational loading as the exposure and lumbar spine structural findings on imaging as the outcomes. When possible, results were pooled.

Results

Seventeen studies were included in the review. Ten studies evaluated the association of occupational loading with disc degeneration (signal intensity), four of which were pooled into a meta-analysis. Of the 10 studies, only two did not identify a relationship between occupation loading and disc degeneration. A meta-analysis including four of the studies demonstrated an association between higher loading and degeneration for all spinal levels, with odds ratios between 1.6 and 3.3. Seven studies evaluated disc height narrowing and seven evaluate disc bulge, with six and five identifying an association of loading and with imaging findings respectively. Three studies evaluated modic changes and one identified and association with occupational load.

Conclusions

There was moderate evidence suggesting a modest association between occupational loading and disc degeneration (signal intensity), and low-quality evidence of an association between occupational loading and disc narrowing and bulging.

A scoping review of biopsychosocial risk factors and co-morbidities for common spinal disorders

OBJECTIVE

The purpose of this review was to identify risk factors, prognostic factors, and comorbidities associated with common spinal disorders.

METHODS

A scoping review of the literature of common spinal disorders was performed through September 2016. To identify search terms, we developed 3 terminology groups for case definitions: 1) spinal pain of unknown origin, 2) spinal syndromes, and 3) spinal pathology. We used a comprehensive strategy to search PubMed for meta-analyses and systematic reviews of case-control studies, cohort studies, and randomized controlled trials for risk and prognostic factors and cross-sectional studies describing associations and comorbidities.

RESULTS

Of 3,453 candidate papers, 145 met study criteria and were included in this review. Risk factors were reported for group 1: non-specific low back pain (smoking, overweight/obesity, negative recovery expectations), non-specific neck pain (high job demands, monotonous work); group 2: degenerative spinal disease (workers' compensation claim, degenerative scoliosis), and group 3: spinal tuberculosis (age, imprisonment, previous history of tuberculosis), spinal cord injury (age, accidental injury), vertebral fracture from osteoporosis (type 1 diabetes, certain medications, smoking), and neural tube defects (folic acid deficit, anti-convulsant medications, chlorine, influenza, maternal obesity). A range of comorbidities was identified for spinal disorders.

CONCLUSION

Many associated factors for common spinal disorders identified in this study are modifiable. The most common spinal disorders are co-morbid with general health conditions, but there is a lack of clarity in the literature differentiating which conditions are merely comorbid versus ones that are risk factors. Modifiable risk factors present opportunities for policy, research, and public health prevention efforts on both the individual patient and community levels. Further research into prevention interventions for spinal disorders is needed to address this gap in the literature.

Low-back pain

Low-back pain is one of the most common painful conditions experienced by humans throughout their life. Some occupational risk factors (namely, heavy manual material handling) may also contribute to the development of low-back pain: due to the high prevalence of both low-back pain and manual material handling in the adult working population, it has been estimated that low-back pain is probably the most common occupational disorder worldwide. Lifetime prevalence of low-back pain has been reported to be as high as 84%, depending on the case definition used, and no age group is spared, even children. Although low-back pain is not a lethal condition, it was estimated at the third rank among all diseases by disability-adjusted life-years in 2010 in the USA, after ischemic heart disease and chronic obstructive pulmonary disease, and at the first rank by years lived with disability. It also ranked high (13th) globally for the same year, in disability-adjusted life-years. Low-back pain is currently classified as nonspecific/specific as to putative cause and as acute (lasting less than 6 weeks), subacute (6-12 weeks), or chronic (more than 12 weeks) according to duration of symptoms. The distinction between nonspecific/specific and acute/subacute/chronic low-back pain is useful not only for epidemiologic studies, but also (mainly) for choosing the appropriate strategy for the diagnosis and treatment of the disorder. Workplace risk factors for low-back pain include manual lifting and whole-body vibration exposure. This chapter will provide an overview of modern concepts of low-back pain (in general) and will then outline some distinctive features of work-related low-back pain.

Commentary: The spine and vibration: whole lotta shaking going on

Commentary on: Holguin N, Martin JT, Elliott DM, Judex S. Low-intensity vibrations partially maintain intervertebral disc mechanics and spinal muscle area during deconditioning. Spine J 2013;13:428-36 (in this issue).

[Review of dose-response relationship between low level vibration and lower back pain]

OBJECTIVES

Whole-body vibration (WBV) with high level acceleration is found in the workplaces of construction and mining, and has been reported to be associated with low back pain (LBP) experienced by operators of heavy vehicles as an occupational health problem. Because the work conditions with exposure to WBV include bending and twisting of the low back and other factors, the causal relationship between WBV and LBP has not yet been affirmed. A review suggesting the dose-response relationship between WBV with low acceleration and LBP has been published, although there is little evidence supporting the causal relationship. Therefore, we reviewed the dose-response relationship between WBV with low acceleration and LBP.

METHODS

We examined original articles which reported a dose-response relationship between WBV and LBP in addition to review articles with almost the same aims.

RESULTS AND DISCUSSION

Studies which examined imaging findings such as CT and MRI, objective indicators of LBP, do not confirm the causal relationship. Although many studies demonstrated a positive relationship between working periods and incidence of LBP, there were very few reports which recognized a dose-response relationship for the vibration acceleration below 1.0 m/s(2) in which the 8-h energy-equivalent, combined frequency-weighted vibration of three diagonal, that is x, y and z, axes (root-sum-of-squares), Asum(8) was used as an index of vibration exposure.

CONCLUSION

This paper reject the hypothesis of a dose-response relationship between WBV with low acceleration and LBP, concluding there is no evidence linking low level exposure to WBV with LBP for the Japan Society for Occupational Health to recommend 0.35 m/s(2)/as of Asum(8) as a tentative occupational exposure limits for WBV.