Disclosed herein is a surgical guide tool for use in total hip replacement surgery. The surgical guide tool may include a customized mating region and a resection guide. The customized mating region and the resection guide are referenced to each other such that, when the customized mating region matingly engages a surface area of a proximal femur, the resection guide will be aligned to guide a resectioning of the proximal femur along a preoperatively planned resection plane.