Power saws are extremely useful tools, enabling all types of materials to be cut and shaped. However, they also have the potential to cause serious hand injuries. The hands are used to guide pieces into the saw, and thus they can be vulnerable.
The severity of the injury can vary tremendously, depending on the specific level at which the injury occurs (fingertip vs. finger vs. hand vs. forearm), the depth of the injury (skin only vs. tendons, nerves, arteries, and bone), and also characteristics of the saw, such as the blade thickness, tooth pattern, and type and force of the saw. Jigsaws will tend to have a finer, sharper cut, whereas a chain saw is much more powerful with an aggressive blade that can tear out more tissue from the hand or finger. For more information, please click on the link.
Information provided by the American Society for Surgery of the Hand