The Preview Shoulder, a 3D total shoulder arthroplasty (TSA) surgical planning software, is a standalone software application which assists the surgeon in planning reverse and anatomic shoulder arthroplasty. Preview Shoulder includes 3D digital representations of implants for placement in images used for surgical planning. Preview Shoulder is a secure software application used by qualified or trained surgeons and is accessed by authorized users. The primary function of Preview Shoulder is to receive and process DICOM CT image(s) of patients. Preview Shoulder can be used to place an implant in the original CT image and place an implant in the 3D model of reconstructed bone. The Preview Shoulder allow the user to perform surgical planning and generate an output surgical report. Preview Shoulder does not provide a diagnosis or surgical recommendation. The surgeon is responsible for selecting and placing the implant model for pre-surgical planning purposes.