Safety and Effectiveness of the Tornier Simpliciti™ Shoulder System in Shoulder Arthroplasty

Inclusion Criteria: * A subject must meet all of the following inclusion criteria in order to enter the study: * Adult subject 18 years or older, * Clinical indication for total shoulder or hemi replacement due to primary diagnosis of osteoarthritis, * Scapula and proximal humerus must have reached skeletal maturity, * Willing and able to comply with the protocol, * Willing and able to personally sign the informed consent form, * Subject is legally competent, understands the nature, significance and implications of the clinical investigation, and is able to form a rational intention in the light of these facts. Exclusion Criteria: * A subject will not be eligible to participate in the study if any of the following conditions is present: * lack of sufficient sound bone to seat and support the implant, including that resulting from skeletal immaturity, osteoporosis or erosive arthritis, * Severe Walch grade B2 glenoid defined as \>60% posterior head displacement and \>20% posterior glenoid bone loss, * metal allergies or sensitivity, * infection at or near the site of implantation, * distant or systemic infection.