Recent literature reports an increase in the rate of shoulder arthroplasties, particularly total shoulder arthroplasties (TSAs), being performed in the United States. However, the national epidemiology of use of hemiarthroplasty (HA) and TSA as treatments for glenohumeral osteoarthritis has not been elucidated. We conducted a study to analyze trends in using HA and TSA as treatments for glenohumeral osteoarthritis from 2000 to 2010, and to compare patient characteristics and inpatient complications. US Nationwide Inpatient Sample patients with a primary inpatient diagnosis of shoulder arthritis and a principal procedure of HA or TSA were identified using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) procedural codes. From 2000 to 2010 the nationally adjusted population rate of shoulder arthroplasty performed for osteoarthritis increased 3.7-fold. Specifically, the population rate of TSA increased 5.0-fold, and that of HA increased 1.9-fold. In 2010, 80.3% of patients having shoulder arthroplasty for arthritis underwent TSA. TSA patients were older (P < .0001) and had a higher mean number of chronic illnesses (P = .034). TSA-associated discharges had a higher rate of surgical and medical care complications (P = .011) and blood transfusions (P = .041) after adjusting for comorbidities.