A combination of - a patient-specific bone implant having a patient-specific external morphology (17, 18, 5 19); and - a customized surgical guide for surgical instruments for placement on the patient-specific bone implant, said customized surgical guide comprising - one or more customized guiding elements (10, 11); - one or more customized surface structures (7, 8, 9) extending over at least part of the patient-specific external morphology of the patient-specific bone implant; and - optionally a connecting structure, connecting said customized guiding elements (10, 11) and said one or more surface structures (7, 8, 9); wherein said customized surgical guide and said patient-specific bone implant engage by means of a unique fit, ensured by the congruency between said patient-specific external morphology (17, 18, 19) and at least one of said one or more customized surface structures (7, 8, 9); and wherein said one or more surface structures (7, 8, 9) and/or the one or more customized guiding elements (10, 11) and/or the optional connecting structure is provided with one or more locking features which ensure a specific interlock of the customized surgical guide with the patient-specific bone implant. - a patient-specific bone implant having a patient-specific external morphology (17, 18, 5 19); and - a customized surgical guide for surgical instruments for placement on the patient-specific bone implant, said customized surgical guide comprising - one or more customized guiding elements (10, 11); - one or more customized surface structures (7, 8, 9) extending over at least part of the patient-specific external morphology of the patient-specific bone implant; and - optionally a connecting structure, connecting said customized guiding elements (10, 11) and said one or more surface structures (7, 8, 9); wherein said customized surgical guide and said patient-specific bone implant engage by means of a unique fit, ensured by the congruency between said patient-specific external morphology (17, 18, 19) and at least one of said one or more customized surface structures (7, 8, 9); and wherein said one or more surface structures (7, 8, 9) and/or the one or more customized guiding elements (10, 11) and/or the optional connecting structure is provided with one or more locking features which ensure a specific interlock of the customized surgical guide with the patient-specific bone implant. - one or more customized guiding elements (10, 11); - one or more customized surface structures (7, 8, 9) extending over at least part of the patient-specific external morphology of the patient-specific bone implant; and - optionally a connecting structure, connecting said customized guiding elements (10, 11) and said one or more surface structures (7, 8, 9); wherein said customized surgical guide and said patient-specific bone implant engage by means of a unique fit, ensured by the congruency between said patient-specific external morphology (17, 18, 19) and at least one of said one or more customized surface structures (7, 8, 9); and wherein said one or more surface structures (7, 8, 9) and/or the one or more customized guiding elements (10, 11) and/or the optional connecting structure is provided with one or more locking features which ensure a specific interlock of the customized surgical guide with the patient-specific bone implant.