[Locking of the intramedullary nail in the medullary cavity of the tibia (author's transl)].

Whether or not an effective locking of the medullary nail in transverse direction is achieved after medullary nailing of the tibia, is a moot point in literature. Researchers agree, however, that the essential locking of the nail occurs on the longitudinal axis of the nail. The authors conducted studies with strain gauges measuring the expansion and introduced together with the nail in order to obtain information on the elastic performance of the nail in transverse and longitudinal direction. The curves plotted from the data obtained, present a typical appearance. After the tibia has been properly reamed, a medullary nail of the AO is subjected to both elastic transverse compression as well as slight longitudinal bending after nailing. In case of excessive reaming the transverse elastic effect is only slight. If, on the other hand, reaming is not effected wide enough, the bone may burst open or the nail may undergo plastic deformation.