[Biomechanical considerations concerning the use of internal fixator systems in spinal interventions].

Three different internal fixateurs ("Dick", "Kluger", "SOCON") were investigated in an in-vitro setting. The systems showed nearly identical deformation under physiological loads. A new definition for the stabilizing capacity indicated a distinct weakness under compressive and torsional loading. In order to avoid early failure of the implant and/or the vertebra-implant interface bracing and a restricted mobilisation is recommended until healing of the fracture/fusion has taken place.