A system for co-relating a preoperative image-based surgical plan for instrumentation to intra-operative images, comprising: at least one processor executing instructions stored on at least one non-transitory storage medium, to cause the at least one processor to: a) based on a surgical plan derived from a preoperative image set, define planned poses for three-dimensional implantable hardware elements for an anatomical part to be instrumented; b) convert the planned poses into a three-dimensional geometric function for the anatomical part to be instrumented; c) process at least one intraoperative three-dimensional image of the anatomical part to be instrumented to identify anatomical features to which the three-dimensional geometric function is to be aligned; d) on the processed intraoperative image, define a range of possible positions for the three-dimensional geometric function; and e) using the identified anatomical features, virtually align the three-dimensional geometric function in the at least one processed intraoperative three-dimensional image, the alignment achieving a position of the implantable hardware elements that is compatible with the surgical plan, without the need to perform registration between the preoperative and intraoperative images, wherein at least one form of artificial intelligence, including machine learning, deep learning or neural networks, and anatomical images are used to identify a range of possible positions for the implantable hardware elements within the at least one three-dimensional intraoperative image, wherein, using an algorithm, a stress minimum as identified by a stress cost function between the implantable hardware elements and the anatomical part into which they are to be implanted is determined during the virtual alignment of the three-dimensional geometric function, wherein the three-dimensional geometric functions for all implantable hardware elements are aligned in combination with analysis of preoperative images showing motion analysis of the anatomical parts to be instrumented, and wherein the stress cost function further takes into account a predicted stress of all implantable hardware elements on all anatomical parts to be instrumented. at least one processor executing instructions stored on at least one non-transitory storage medium, to cause the at least one processor to: a) based on a surgical plan derived from a preoperative image set, define planned poses for three-dimensional implantable hardware elements for an anatomical part to be instrumented; b) convert the planned poses into a three-dimensional geometric function for the anatomical part to be instrumented; c) process at least one intraoperative three-dimensional image of the anatomical part to be instrumented to identify anatomical features to which the three-dimensional geometric function is to be aligned; d) on the processed intraoperative image, define a range of possible positions for the three-dimensional geometric function; and e) using the identified anatomical features, virtually align the three-dimensional geometric function in the at least one processed intraoperative three-dimensional image, the alignment achieving a position of the implantable hardware elements that is compatible with the surgical plan, without the need to perform registration between the preoperative and intraoperative images, a) based on a surgical plan derived from a preoperative image set, define planned poses for three-dimensional implantable hardware elements for an anatomical part to be instrumented; b) convert the planned poses into a three-dimensional geometric function for the anatomical part to be instrumented; c) process at least one intraoperative three-dimensional image of the anatomical part to be instrumented to identify anatomical features to which the three-dimensional geometric function is to be aligned; d) on the processed intraoperative image, define a range of possible positions for the three-dimensional geometric function; and e) using the identified anatomical features, virtually align the three-dimensional geometric function in the at least one processed intraoperative three-dimensional image, the alignment achieving a position of the implantable hardware elements that is compatible with the surgical plan, without the need to perform registration between the preoperative and intraoperative images, wherein at least one form of artificial intelligence, including machine learning, deep learning or neural networks, and anatomical images are used to identify a range of possible positions for the implantable hardware elements within the at least one three-dimensional intraoperative image, wherein, using an algorithm, a stress minimum as identified by a stress cost function between the implantable hardware elements and the anatomical part into which they are to be implanted is determined during the virtual alignment of the three-dimensional geometric function, wherein the three-dimensional geometric functions for all implantable hardware elements are aligned in combination with analysis of preoperative images showing motion analysis of the anatomical parts to be instrumented, and wherein the stress cost function further takes into account a predicted stress of all implantable hardware elements on all anatomical parts to be instrumented.