A surgical instrument includes a female branch defining in a coupling area a hollow volume including inwardly facing inner coupling surfaces and including a male branch which can be pivoted relative to the female branch at least partly inside the hollow volume about a pivot axis, the male branch defining in the coupling area a guide portion having outwardly facing outer coupling surfaces in which outer coupling recesses are arranged, wherein on the inner coupling surfaces, inner coupling recesses are arranged which extend relative to a longitudinal axis of the surgical instrument in a direction other than that of the outer coupling recesses.