# US 10,117,680 B2 · Osteosynthesis device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,117,680 B2 - Document ID: US10117680B2 - Status: Granted - Kind: B2 - Application number: 15/500,981 - Filed: 2015-07-15 - Published: 2017-07-27 - Granted: 2018-11-06 - Earliest claimed: 2014-08-06 - Assignees: Silony Medical International AG - Applicants: Silony Medical International AG - Inventors: Frank Thilo Trautwein; Frank Heuer; Timo Ohnmacht - Web page: https://patentgrep.com/patent/US10117680B2 ## CPC - A61B 17/7037: {wherein pivoting is blocked when the rod is clamped} - A61B 17/7032: {Screws or hooks with U-shaped head or back through which longitudinal rods pass} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract The invention relates to an osteosynthesis device having a bone screw (12), which has a threaded shaft (24) and a ball head (26), and having a fork head (14), which has a groove (32) and two legs (34), the ball head (26) being pivotably supported in the fork head (14), and having a pressure piece (16), which is seated on the ball head (26), the pressure piece (16) being braced on the fork head (14) and having two lateral fins (48) extending in the axial direction (30) of the fork head (14) and away from the threaded shaft (24); it is proposed that the pressure piece (16) is supported in the fork head (14) with prestressing in the axial direction (30) and thus in the direction toward the ball head (26) in that at least one of the fins (48) is slit transversely to the axial direction (30) of the fork head (14), so that a slit (50) forms a spring tongue (52), and the pressure piece (16) is thereby resiliently embodied and is braced via the spring tongue (52) on the fork head (14), and that a protrusion (70) protrudes in the axial direction (30) into the slit (50); and that the protrusion (70), for limiting deformation or deflection of the spring tongue (52), forms a stop (72), acting in the axial direction (30), for the spring tongue (52). ## Claims ### Claim 1 An osteosynthesis device, comprising: a bone screw (12) which has a threaded shaft (24) and a ball head (26), and having a fork head (14) which has a groove (32) and two legs (34) for receiving a connection rod (18), the ball head (26) being pivotably supported in the fork head (14), and having one single pressure piece (16) which is seated on the ball head (26), the pressure piece (16) being braced on the fork head (14) and having two lateral fins (48) extending in an axial direction (30) of the fork head (14) and away from the threaded shaft (24), the one single pressure piece being constructed and arranged to be directly contacted by the connection rod (18), wherein the pressure piece (16) is supported in the fork head (14), with prestressing in the axial direction (30) and thus the direction toward the ball head (26) and wherein at least one of the fins (48) is slit transversely to the axial direction (30) of the fork head (14), so that a slit (50) extending in a circumferential direction and extending radially through the fin (48) is formed which slit (50) forms a spring tongue (52), and the pressure piece (16) is thereby resiliently embodied and is braced via the spring tongue(52) on the fork head (14); and wherein a protrusion (70) embodied in one piece with the pressure piece (16) protrudes in the axial direction (30) into the slit (50); and wherein the protrusion (70), for limiting deformation or deflection of the spring tongue (52), forms a stop (72), acting in the axial direction (30), for the spring tongue (52). ### Claim 2 (depends on 1) The osteosynthesis device of claim 1, characterized in that the protrusion (70) is embodied opposite, in the axial direction (30), the spring tongue (52) on the pressure piece (16). ### Claim 3 (depends on 1) The osteosynthesis device of claim 1, characterized in that the protrusion (70) is embodied on the spring tongue (52). ### Claim 4 (depends on 1) The osteosynthesis device of claim 1, characterized in that the protrusion (70) is embodied on a free end (54) of the spring tongue (52) or on a region of the pressure piece opposite the free end of the spring tongue in the axial direction. ### Claim 5 (depends on 1) The osteosynthesis device of claim 1, characterized in that the pressure piece (16) and its fins (48) are embodied axially symmetrically, to the axial direction (30) of the fork head (14). ### Claim 6 (depends on 1) The osteosynthesis device of claim 1, characterized in that the pressure piece (16) and its fins (48) are embodied mirror-symmetrically to a plane that includes the axial direction (30) of the fork head. ### Claim 7 (depends on 1) The osteosynthesis device of claim 1, characterized in that the slit (50) is embodied in rounded fashion on a closed end (56) of the spring tongue (52). ### Claim 8 (depends on 1) The osteosynthesis device of claim 1, characterized in that the deflection of the spring tongue (52), upon a clasping or latching or screwing in of the pressure piece into an installed position in the fork head (14), amounts to at most 1.0 mm. ### Claim 9 (depends on 1) The osteosynthesis device of claim 1, characterized in that on outer sides of the fins (48) of the pressure piece (16), there are protrusions (60) or recesses, which cooperate in intermeshing fashion with recesses (62) or protrusions on inside surfaces of the legs (34) of the fork head (14). ### Claim 10 (depends on 1) The osteosynthesis device of claim 1, characterized in that the pressure piece (16) engages a graduation, located on an inner side of a leg (34) of the fork head (14), from beneath or engages the inside of a recess embodied there. ### Claim 11 (depends on 1) The osteosynthesis device of claim 1, characterized in that one fin (48) or both fins of the pressure piece (16) are embodied with multiple slits, which are cut inward into the fin or fins (48) in alternation from one side and a side opposite that side transversely to the axial direction (30) of the fork head (14). ### Claim 12 (depends on 1) The osteosynthesis device of claim 1, characterized in that the pressure piece (16) directly or indirectly forms a support for a connecting rod (18). ### Claim 13 (depends on 1) The osteosynthesis device of claim 1, characterized in that the pressure piece (16) is secured against relative rotation with respect to the fork head (14). ### Claim 14 (depends on 1) The osteosynthesis device of claim 1, characterized in that the spring tongue (52) is embodied as thicker on a free end (54) in the radial and/or axial direction than at a closed end (56). ### Claim 15 An osteosynthesis device comprising a bone screw (12) which has a threaded shaft (24) and a ball head (26), and having a fork head (14) which has a groove (32) and two legs (34) for receiving a connection rod (18), the ball head (26) being pivotably supported in the fork head (14), and having one single pressure piece (16) which is seated on the ball head (26), the pressure piece (16) being braced on the fork head (14) and having two lateral fins (48) extending in an axial direction (30) of the fork head (14) and away from the threaded shaft (24), the one single pressure piece being constructed and arranged to be directly contacted by the connection rod (18), wherein the pressure piece (16) is supported in the fork head (14) with prestressing in the axial direction (30) and thus the direction toward the ball head (26) and wherein at least one of the fins (48) is slit transversely to the axial direction (30) of the fork head (14), so that a slit (50) extending in a circumferential direction and extending radially through the fin (48) is formed which slit (50) forms a spring tongue (52) on the fork head (14); and that the spring tongue (52), in a state in which it is installed on the fork head but is not in an additionally axially stressed state, is spaced apart at a closed end (56), is joined to the fin (48), from the fork head (14) in the axial direction (30); and wherein the spring tongue (52), in the additionally axially stressed state, in the vicinity of its end (56) joined to the fin (48) forms a stop (74) and can be braced with the stop (74) against the fork head (14) for limiting more-extensive deformation or deflection of the spring tongue (52). ### Claim 16 (depends on 15) The osteosynthesis device of claim 15, characterized in that the deflection of the spring tongue (52), upon a clasping or latching or screwing in of the pressure piece into an installed position in the fork head (14), amounts to at most 1.0 mm. ### Claim 17 An osteosynthesis device, comprising: a bone screw (12) which has a threaded shaft (24) and a ball head (26), and having a fork head (14) which has a groove (32) and two legs (34) for receiving a connection rod (18), the ball head (26) being pivotably supported in the fork head (14), and having one single pressure piece (16) which is seated on the ball head (26), the pressure piece (16) being braced on the fork head (14) and having two lateral fins (48) extending in an axial direction (30) of the fork head (14) and away from the threaded shaft (24), the one single pressure piece being constructed and arranged to be directly contacted by the connection rod (18), wherein the pressure piece (16) is supported in the fork head (14), with prestressing in the axial direction (30) and thus the direction toward the ball head (26) and wherein at least one of the fins (48) is slit transversely to the axial direction (30) of the fork head (14), so that a slit (50) extending in a circumferential direction and extending radially through the fin (48) is formed which slit (50) forms a spring tongue (52), and the pressure piece (16) is thereby resiliently embodied and is braced via the spring tongue (52) on the fork head (14); and wherein a protrusion (70) embodied in one piece with the pressure piece (16) protrudes in the axial direction (30) into the slit (50) and is embodied opposite the spring tongue (52) on the pressure piece (16); and that the protrusion (70), and wherein the protrusion (70) for limiting deformation or deflection of the spring tongue (52), forms a stop (72), acting in the axial direction (30), for the spring tongue (52) and that the deflection of the spring tongue (52), upon a clasping or latching or screwing in of the pressure piece into an installed position in the fork head (14), amounts to at most 1.0 mm.