A combination of- a patient-specific bone implant and- a customized surgical guide for surgical instruments for placement on a patient-specific bone implant, said customized surgical guide comprising- one or more customized guiding elements- one or more surface structures extending over at least part of the surface of the patient-specific bone implant and optionally- a connecting structure, connecting said customized guiding elements and said one or more surface structureswherein said one or more surface structures and/or the one or more guiding elements and/or the connecting structure is provided with one or more locking features which ensure a specific interlock of the customized surgical guide with the patient-specific implant.