Abstract: The invention makes it possible to determine a force vector that is applied to a tip of a minimally invasive surgical instrument. The force acts upon the housing, is directed to the base, and causes a deformation there in special beam structures. Said deformation is detected by means of tension-sensitive/extension-sensitive resistors whose changes are a measure for the applied force vector. The inventive measuring element comprises special mounting elements so as to be integrated into tube-type instruments such as guiding wires, fastening zones for additional components, an overload protection, and a head shape that is adapted to the treatment process.