Current concepts of shoulder arthroplasty for radiologists: Part 1--Epidemiology, history, preoperative imaging, and hemiarthroplasty.

OBJECTIVE The purpose of this article is to provide a review of indications for shoulder arthroplasty, describe preoperative imaging assessment, present new and modified designs of shoulder arthroplasty, illustrate normal and abnormal postoperative imaging findings, and review key radiographic measurements. CONCLUSION Knowledge of the physiologic purpose, orthopedic trends, imaging findings, and complications is important in assessing shoulder prostheses.