Abstract: The invention relates to an osteosynthesis device with a bone plate and with at least one bone screw, wherein the bone plate has at least one through-hole with a conical inner thread formed at least in part in the through-hole. Moreover, the bone screw has a screw shank and also a screw head with a conical thread, with the possibility of forming a connection at a variable and stable angle between bone screw and bone plate by receiving the screw head with conical outer thread in the respective through-hole of the bone plate. According to the invention, the thread in the screw head has a first portion A with a first conicity and a second portion B with a second conicity, wherein a zone of discontinuity with respect to the conicity is present between the first portion A and the second portion B.

Abstract: The invention relates to an osteosynthesis device with a bone plate and with at least one bone screw, wherein the bone plate has at least one through-hole with a conical inner thread formed at least in part in the through-hole. Moreover, the bone screw has a screw shank and also a screw head with a conical thread, with the possibility of forming a connection at a variable and stable angle between bone screw and bone plate by receiving the screw head with conical outer thread in the respective through-hole of the bone plate. According to the invention, the thread in the screw head has a first portion A with a first conicity and a second portion B with a second conicity, wherein a zone of discontinuity with respect to the conicity is present between the first portion A and the second portion B.