[Identification and determination of age of needle tracks in human skin (author's transl)].

Examination of enzymic activities and histochemical reactions on needle pricks can be used to determine the age of micro-injuries with sufficient exactness. Well preserved skin shows patterns of enzymes which also appear with other skin injuries and which were described in detail especially by Raekallio (1970, 1972). In autolytical changes of the skin the adenosinetriphosphatase-reaction is still reliable and can be successfully estimated. If one has sufficient experience it is possible to fairly exactly estimate the age of an injury within the first hour after the injury by preparation of the adenosinetriphosphatase-reaction. If the times of injections are known one frequently succeeds in determining the time of death by exactly determining the age of the injury. In legal expertises the histochemical reactions can rightly be regarded as useful indications of a certain age of the injury. But they do not allow an exact estimate "beyond a reasonable doubt".