This invention relates to a method for manufacturing an individualized immobilization element for the non-invasive immobilization and/or mobilization of at least a segment of a body part of a patient in a predetermined position relative to a reference and/or in a pre-certain configuration. The method comprises the steps of (i) providing a data set that comprises a three-dimensional image of an outer contour of at least a part of the segment of the body part to be immobilized and/or mobilized and (ii) the manufacture of at least a part of the immobilization element by rapid manufacturing of a shape on the basis of said data set using a polymeric material containing a thermoplastic polymer having a melting point less than or equal to 100° C., wherein the polymer material contains a nucleating agent for enhancing the of the crystallization of the thermoplastic polymer.