Search

Objective: This study described the effects of applied force (grip) on vascular and sensorineural function in an animal model of hand-arm vibration syndrome (HAVS)., Methods: Rat tails were exposed to 0, 2, or 4 N of applied force 4 hr/d for 10 days. Blood flow and sensitivity to transcutaneous electrical stimulation and pressure were measured., Results: Applied force increased blood flow but reduced measures of arterial plasticity. Animals exposed to force tended to be more sensitive to 250-Hz electrical stimulation and pressure applied to the tail., Conclusions: Effects of applied force on blood flow and sensation are different than those of vibration. Studies examining co-exposures to force and vibration will provide data that can be used to determine how these factors affect risk of workers developing vascular and sensorineural dysfunction (ie, HAVS)., Competing Interests: Krajnak, Warren, Xu, Chapman, Waugh, Boots, Welcome, and Dong have no relationships/conditions/circumstances that present potential conflict of interest., (Copyright © 2023 Written work prepared by employees of the Federal Government as part of their official duties is, under the U.S. Copyright Act, a “work of the United States Government” for which copyright protection under Title 17 of the United States Code is not available. As such, copyright does not extend to the contributions of employees of the Federal Government.)

Background: Workers who stand on platforms or equipment that vibrate are exposed to foot-transmitted vibration (FTV). Exposure to FTV can lead to vibration white feet/toes resulting in blanching of the toes, and tingling and numbness in the feet and toes., Objectives: The objectives are 1) to review the current state of knowledge of the health risks associated with foot-transmitted vibration (FTV), and 2) to identify the characteristics of FTV and discuss the associated risk of vibration-induced injury., Participants: Workers who operated locomotives (n=3), bolting platforms (n=10), jumbo drills (n=7), raise drilling platforms (n=4), and crushers (n=3), participated., Methods: A tri-axial accelerometer was used to measure FTV in accordance with ISO 2631-1 guidelines. Frequency-weighted root-mean-square acceleration and the dominant frequency are reported. Participants were also asked to report pain/ache/discomfort in the hands and/or feet., Results: Reports of pain/discomfort/ache were highest in raise platform workers and jumbo drill operators who were exposed to FTV in the 40 Hz and 28 Hz range respectively. Reports of discomfort/ache/pain were lowest in the locomotive and crusher operators who were exposed to FTV below 10 Hz. These findings are consistent with animal studies that have shown vascular and neural damage in exposed appendages occurs at frequencies above 40 Hz., Conclusions: Operators exposed to FTV at 40 Hz appear to be at greater risk of experiencing vibration induced injury. Future research is required to document the characteristics of FTV and epidemiological evidence is required to link exposure with injury.

Occupational exposure to vibration through the use of power- and pneumatic hand-tools results in cold-induced vasospasms, finger blanching, and alterations in sensorineural function. Collectively, these symptoms are referred to as hand-arm vibration syndrome (HAVS). Currently the International Standards Organization (ISO) standard ISO 5349-1 contains a frequency-weighting curve to help workers and employers predict the risk of developing HAVS with exposure to vibration of different frequencies. However, recent epidemiological and experimental evidence suggests that this curve under-represents the risk of injuries to the hands and fingers induced by exposure to vibration at higher frequencies (>100 Hz). To improve the curve, better exposure-response data need to be collected. The goal of this review is to summarize the results of animal and computational modeling studies that have examined the frequency-dependent effects of vibration, and discuss where additional research would be beneficial to fill these research gaps.

Background: Previous studies have suggested that the presence of the vascular component of hand-arm vibration syndrome (HAVS) in the hands increases the risk of cold-induced vasospasm in the feet., Aims: To determine if objectively measured cold-induced vasospasm in the hands is a risk factor for objectively measured cold-induced vasospasm in the feet in workers being assessed for HAVS., Methods: The subjects were 191 male construction workers who had a standardized assessment for HAVS including cold provocation digital photocell plethysmography of the hands and feet to measure cold-induced vasospasm. Bivariate analysis and multinomial logistic regression were used to examine the association between plethysmographic findings in the feet and predictor variables including years worked in construction, occupation, current smoking, cold intolerance in the feet, the Stockholm vascular stage and plethysmographic findings in the hands., Results: Sixty-one (32%) subjects had non-severe vasospasm and 59 (31%) had severe vasospasm in the right foot with the corresponding values being 57(30%) and 62 (32%) in the left foot. Multinomial logistic regression indicated that the only statistically significant predictor of severe vasospasm in the feet was the presence of severe vasospasm in the hands (OR: 4.11, 95% CI: 1.60-10.6, P < 0.01 on the right side and OR: 4.97, 95% CI: 1.82-13.53, P < 0.01 on the left side). Multinomial logistic regression analysis did not indicate any statistically significant predictors of non-severe vasospasm in the feet., Conclusions: Workers assessed for HAVS frequently have cold-induced vasospasm of their feet. The main predictor of severe vasospastic foot abnormalities is severe cold-induced vasospasm in the hands.

Background Hand–arm vibration syndrome (HAVS) refers to the neurological, vascular and musculoskeletal problems that may arise due to exposure to segmental vibration to the hands. An analogous syndrome may occur in the lower extremities of workers exposed to foot-transmitted vibration.Aims This report describes the case of a worker with a history of foot-transmitted vibration exposure presenting with cold intolerance in the feet and blanching in the toes.Case report A 54-year-old miner presented with a chief complaint of blanching and pain in his toes. The worker had a history of foot-transmitted vibration exposure over his 18 year career as a miner, primarily from the operation of vehicle-mounted bolting machines. Cold provocation digital plethysmography showed cold-induced vasospastic disease in the feet, but not in the hands.Conclusions This case illustrates a condition descriptively termed ‘vibration-white foot’: a disease analogous to HAVS arising after segmental vibration exposure to the feet. Further research is required to increase awareness of, and direct preventive efforts for, this potentially debilitating condition. [ABSTRACT FROM AUTHOR]