Abstract: A surgical saw has a sector-shaped saw blade mounted on a shaft. The shaft is surrounded by a coaxial second shaft to which an eccentric member is mounted close to a saw blade and parallel therewith. Both shafts and thus the eccentric member and the cutting blade can be rotated with respect to each other and can be fixed in their rotational position. Depending on the rotational position, the saw blade is either covered by the eccentric member in a rest position to be inserted in a hollow bone, or is indexed in a position to be freely and gradually exposed to make a sawing operation possible.