[Harvesting small amounts of autogenous spongiosa with a new set of instruments].

A new set of instruments with a special saw, a guide and a punch has been developed for harvesting of cancellous bone for small grafts. In a cadaver experiment use of the instruments was compared with the conventional open technique. Within half the operation time, nearly the same quantity of cancellous bone could be salvaged. In 29 clinical cases, bone defects resulting from 4 bone cysts, 6 enchondromas, 5 pseudarthroses and 5 fractures were closed with cancellous bone grafts harvested by means of the new instruments. In the case of 9 bone tumors the punches were used to obtain biopsy specimens, and sufficient tissue for the exclusion of malignancy was obtained in all 9. With the new instruments we are able to harvest cancellous bone for small grafts by a minimally invasive method.