VWF is largely associated with hand-held oscillating pneumatic tools, such as metal grinders and pneumatic drills. It is also associated with chain saws and with powered tools causing repetitive impact, such as riveters and impact wrenches. The mechanisms producing Raynaud's in the setting of hand-arm vibration are not fully understood. However, there is evidence for a sympathetically mediated constriction of small arteries in the hand, interrupting cutaneous blood flow. There is also evidence of impaired dilatation of larger arteries.
Vibration can also diminish the blood flow to the intervertebral disc.
Unfortunately, the lumbar intervertebral disc is avascular, and its nutritional supply comes from diffusion through blood vessels surrounding the annulus fibrosus and under the hyaline end plate cartilage. Diminished blood flow to the cartilage end plate would limit the ability of the disc to maintain the degree of hydration necessary to provide support for the lumbar spine during loading. In the hand, direct pressure over the hypothenar eminence can also occlude the ulnar artery and result in hypothenar hammer syndrome. Thus, it appears that vascular changes resulting from work exposures may contribute to the development or manifestation of MSDs. Extrinsic ischemic compression, while not an intrinsic disease of blood vessels, is also considered here to complete the discussion of vascular responses to work exposures.