Arterial abnormalities in the hands of workers with vibration white fingers – a magnetic resonance angiography case series

Vibration white finger (VWF) is a complication from exposure to hand-arm vibrations. Poor knowledge of the pathophysiology of VWF means that making an accurate prognosis is difficult. Thus, a better understanding of VWF’s pathophysiology is of importance.The purpose of this study was to investigate whether there were arterial abnormalities in the hands in patients with VWF and a positive Allen’s test, using ultrasound and MRA imaging.This was a case series where arterial abnormalities in the hands were investigated in ten participants with VWF and using prolonged Allen’s test (> 5 s). The participants had an average vibration exposure of 22 years and underwent Doppler ultrasound and Magnetic Resonance Angiography (MRA) to check for arterial abnormalities.The participants had VWF classified as 1–3 on the Stockholm workshop scale. Ultrasound and MRA identified vascular abnormalities in all participants, the predominant finding was missing or incomplete superficial arch. Also, stenosis was identified in four participants.This study reveals a high proportion of arterial stenosis and abnormalities in patients with VWF and a prolonged Allen’s test.

Vibration and Noise Transmitted by Agricultural Backpack Powered Machines Critically Examined Using the Current Standards

European Directives 2002/44/EC and 2003/10/EC establish the exposure limit values for preventing operators’ risks to vibration and noise transmitted by machines. Few studies studied noise and vibration of agricultural backpack powered machines (as mist blowers and blowers), but nobody critically studied them. This work analyzed the field back vibration, hand-arm vibration (HAV), and noise transmitted to ten operators by eight blowers and mist blowers. Unweighted and weighted vibration were analyzed, using the standards ISO 2631-1 (back), and ISO 5349-1 and ISO/TR 18570 (hand-arm system). The noise was evaluated by recording the acoustic pressure level at the operators’ ears using the ISO 9612. With the ISO 2631-1, the vibration to the operators’ back was low (0.38 ms−2), but the unweighted vibration measured along y and z-axes (not used by the ISO 2631-1) were high (>11 ms−2). HAV were also low when using the ISO 5349-1 (the highest value was 2.51 ms−2 in mist blowers), but high with the ISO/TR 18570 for the onset of vibration white finger (1446 ms−1.5 in blowers). Noise levels were always high: more than 100 dB(A), excluding the blower with the exhaust inside the blower hose. This last machine had noise levels lower than 86 dB(A), but its specific feature could increase environmental pollution.

Biomechanical Modeling of Human Finger

Many of the studies in the biomechanics of the human body made globally focused primarily on hand-arm. This segment of the human body is considered a "gateway" of vibrations to other parts of the body or to internal organs. A long-term exposure to these mechanical vibration (caused by vibrating hand equipment: drill, grinder, etc.) affects the soft tissues and may lead to a dangerous syndrome, that is particularly vibration white finger (VWF), which is narrowing of blood vessels, a phenomenon that in time and untreated can even cause gangrene. This article focuses on a dynamic model with three degrees of freedom of the human finger. Some dynamic characteristics, such as centre of gravity, stiffness and damping, using both a rigid body structure system and computer simulations can be determined after measuring the vibrations.

Vascular

Vascular anatomy 592Vascular assessment 600Hand–arm vibration syndrome (Vibration white finger) 604Vascular anomalies 606Acute vascular injury 612Occlusion 614Raynaud's disease 617Compartment syndrome 618• This is divided into three parts by the scalenus anterior muscle (this lies over the 2nd part)....

Ergonomic Field Assessment of Bucking Bars during Riveting Tasks

Riveting tasks in aircraft manufacturing results in exposure to vibration from both rivet guns and bucking bars. Long term exposure to vibration has been associated with symptoms of vibration white finger and musculoskeletal disorders. Four different bucking bars of the same shape but different material and mass characteristics (90% tungsten, >90% tungsten, cold rolled and stainless steel) were investigated for vibration and grip muscle activity during a riveting task. The >90% and 90% tungsten bars (3.4 m/s2 and 3.6 m/s2, respectively) resulted in significantly less mean resultant weighted acceleration when compared to the cold rolled and stainless steel (5.3 m/s2 and 5.6 m/s2, respectively), whereas there was no difference in mean hand grip flexor or extensor muscle activity. These results suggest that for bucking tasks that allow access for the bucking bar size investigated, use of heavier but same sized tungsten bucking bars can reduce vibration transmission to the hand.