Locking nails for the medullary space, and an application method

摘要

According to the prior art, the bores in the locking nail are provided with screw threads. After insertion of the nail the cortical or compact substance must also be provided with a screw thread for fixation of the transverse bolt. However, this entails the great risk of the nail screw thread becoming unusable despite the use of expensive aiming devices, and of metal particles reaching the medullary space. The solution is a locking nail made of a tissue-compatible metal and an inner body likewise made of a tissue-compatible material which has a lower deformation strength than the outer body. The inner body is designed such that it fills out the outer body or touches it on at least three points. The inner body is also provided with transverse holes whose position and arrangement correspond to those of the outer body but whose diameter is smaller than that of the outer body. The screw thread in the inner body is a self-tapping screw thread as a result of the transverse screws. This avoids the production of turnings which may reach the medullary space. The complete filling of the outer body prevents spongy substance from growing in and facilitates subsequent removal of the medullary space nail.