000022716 001__ 22716
000022716 005__ 20220110134523.0
000022716 04107 $$aeng
000022716 046__ $$k2018-05-14
000022716 100__ $$aČada, R.
000022716 24500 $$aEvaluation of locking bone screw heads

000022716 24630 $$n24.$$pEngineering Mechanics 2018
000022716 260__ $$bInstitute of Theoretical and Applied Mechanics of the Cech Academy of Sciences, Prague
000022716 506__ $$arestricted
000022716 520__ $$2eng$$aWhen extracting a trauma/orthopaedic titanium alloy implant, there are some difficulties in trying to release some locking bone screws from locking holes of the angularly stable plates (stripping the internal hexagon in the screw heads or twisting off the screw). Experimentally, the magnitude of the torque that causes stripping of the internal hexagon (the Inbus type head) of 3.5 mm locking cortical bone screw made of titanium alloy Ti6Al4V according to ISO 5832-3 was determined. It has been experimentally found that slipping the end of a screwdriver with a hexagonal end inside the head of the locking cortical bone screw when stripping the internal hexagon causes a deformation of the screw head circumference and thus increases the thread friction. The influence of the tightening torque on the ability to unscrew the locking cortical bone screw from the locking hole of the angularly stable plate was evaluated experimentally. The numerical assessment of the five alternatives of the head shapes of the locking cortical bone screws in terms of stresses and resulting deformations has shown that the screw with the Torx type head, which reaches the lowest values of reduced stress and plastic deformation, is the best option.

000022716 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000022716 653__ $$alocking bone screw, osteosynthesis, biomechanics, experiments, FEM

000022716 7112_ $$aEngineering Mechanics 2018$$cSvratka, CZ$$d2018-05-14 / 2018-05-17$$gEM2018
000022716 720__ $$aČada, R.$$iFrydrýšek, K.$$iSejda, F.$$iTiller, P.
000022716 8560_ $$ffischerc@itam.cas.cz
000022716 8564_ $$s1085291$$uhttps://invenio.itam.cas.cz/record/22716/files/133.pdf$$yOriginal version of the author's contribution in proceedings, page , section BIO.
000022716 962__ $$r21225
000022716 980__ $$aPAPER