Osteosynthesis device

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).

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.