An assembly tool for affixing a modular femoral head prosthesis to a femoral stem prosthesis during total hip arthroplasty may be provided. The assembly tool may be utilized in conjunction with prosthetic femoral components having a Morse taper arrangement. A predetermined amount of force may be calculated to properly set the prosthetic components. The assembly tool may include hemicylindrical bearings, a clamp, and an impaction cap having extension members connected thereto. The hemicylindrical bearings may be mounted on the neck portion of the femoral stem prosthesis and removably secured thereto via a vice-like clamp. Extension members may attach to the hemicylindrical bearings and extend around the femoral head to an impaction cap. The impaction cap may be mounted on the femoral head and provide the linear biasing force necessary to secure the femoral head to the femoral stem.
