VIBROEXTRACTOR FOR THREADED FRAGMENTS OF TRANSPEDICULAR SCREWS Russian patent published in 2017 - IPC A61B17/88 A61B17/92 

FIELD: medicine.

SUBSTANCE: invention relates to medical equipment, namely to devices for extraction of threaded fragments of transpedicular screws from bone tissue. Vibroextractor represents bar system consisting of series axisymmetrical placed in cylindrical body between handle and head in form of cup magnetostrictive converter of electromagnetic energy in longitudinal mechanical vibrations and stepped half-wave oscillation concentrator, output end of which is in contact with aprons of segment inserts installed in cavity of head, on inner conical surfaces of which there are helical engagement elements (blades), forming multiple-flight conical thread with large pitch. Excited by transducer longitudinal mechanical high-frequency oscillations are amplified by stepped concentrator and transmitted to engagement elements improving process of forming recesses on top of fragment of thread turns of screw being turned out of bone tissue, thereby promoting improvement of reliability and reduced axial force and torque applied to handle.

EFFECT: higher reliability of engagement and reduced axial force and torque applied to handle.

1 cl, 6 dwg