A computer-assisted and automatic identification of possible cranial positions for any kind of implant is presented. In this method, skull data of the individual patient's skull are used as well as statistical skull data which include so-called skull avoidance zones. Further, a digital template of the implant is used to find these possible positions. The implant may be e.g. an IPG and/or the screws of a fixation frame, but these are only embodiments of implants and other implants may be used with the present invention as well.The computer-implemented medical method of the present invention removes the uncertainty whether a given patient can safely receive an implant, like for example a cranial IPG, which was previously only possible on the basis of human judgement. Furthermore, the present invention removes the uncertainty whether a given patient can be safely fixated in a stereotactic frame or a Mayfield head clamp. The present invention supports the localization of optimal implant location as well as neuro-navigation guided execution of surgery. This enhances safety and speed of the entire medical procedure, as will be explained in more detail hereinafter. The advantages described herein before are in the same way realized by the computer program, the medical system and the navigation system for computer-assisted surgery of the present invention.L'invention concerne une identification assistée par ordinateur et automatique de positions crâniennes possibles pour tout type d'implant. Dans ce procédé, des données crâniennes du crâne d'un patient individuel sont utilisées, ainsi que des données crâniennes statistiques, qui comprennent ce qu'on appelle des zones d'évitement sur le crâne. En outre, un modèle numérique de l'implant est utilisé pour trouver ces positions possibles. L'implant peut par exemple être un générateur implantable d'impulsions et/ou les vis d'un cadre de fixation, mais ceux-ci ne représentent que des modes de réalisation d'implants et d'autres imp
