| 摘要 |
In an apparatus for the osteosynthesis of bone fractures by means of locked endomedullary nailing, a tubular nail ( 1 ), able to be inserted in a medullar channel ( 3 ) of a bone ( 4 ), has a coaxial through internal channel ( 2 ) and has transverse through holes ( 5 a , 5 b , 5 c , 5 d) whose axis ( 6 a , 6 b , 6 c , 6 d) intersects the axis ( 7 ) of the nail ( 1 ). A device for locating the axis ( 6 a) of a predetermined hole ( 5 a) selected between said holes ( 5 a , 5 b , 5 c , 5 d), along which the bone ( 4 ) is to be drilled to drive a corresponding screw for locking the nail ( 1 ) on the bone ( 4 ), comprises a source ( 8 ) of electromagnetic power, an emitter ( 9 ) of the electromagnetic power in the form of non ionising electromagnetic radiation, a line ( 15 ) for transmitting the electromagnetic power from the source ( 8 ) to the emitter ( 9 ). The emitter ( 9 ) can be inserted inside the nail ( 1 ) along the internal channel ( 2 ), from a proximal end ( 10 ) of the nail ( 1 ) at least to a working position, located on the axis ( 6 a) of the predetermined hole ( 5 a), in which at least part of the non ionising electromagnetic radiation is directed from the emitter ( 9 ), through the predetermined hole ( 5 a), on an inner superficial portion ( 11 ) of the cortex ( 12 ) of the bone ( 4 ) corresponding to the bone ( 6 a) of the predetermined hole ( 5 a) and generates, beyond an outer superficial portion ( 13 ) of the cortex ( 12 ) of the bone ( 4 ), also corresponding to the axis ( 6 a) of the predetermined hole ( 5 a), a signal ( 14 ) detectable from the exterior having intensity distribution with centroid in correspondence with the axis ( 6 a) of the predetermined hole ( 5 a).
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