Abstract: A trial medical instrument for aligning an acetabular component, comprising: a first portion configured to fit within a patient's acetabulum; and a second portion extending from the first portion; wherein the second portion extends from the first portion in a direction that mimics a shape formed by a femoral implant component coupled with an acetabular implant component when a femur to which the femoral implant component is coupled is in a position relative to an acetabulum to which the acetabular implant component is coupled that is near an extent of a typical range of motion of the femur. As used herein, the phrase “extent of a typical range of motion” describes typical angular displacements of a femur as usually limited by patient anatomy.