Global® AP™ Total Shoulder Arthroplasty

Inclusion Criteria: * Patients selected for inclusion will present for primary shoulder arthroplasty with a diagnosis of osteoarthritis and will consent to participate. Exclusion Criteria: * Are under 18 years of age or over 70 * Diagnosis of AVN, Inflammatory Arthritis, Fracture or Malunion. * Have a hemi-arthroplasty * Have destruction of the proximal humerus that precludes rigid fixation of the humeral component * Have arthritis with insufficient cuff tissue * Have had a failed rotator cuff surgery * Have loss of musculature, neuromuscular compromise or vascular deficiency in the affected limb rendering the procedure unjustified * Have evidence of active infection * Present with a condition of neuromuscular compromise of the shoulder (e.g., neuropathic joints or brachial plexus injury with a flail shoulder joint) - Have a known active metastatic or neoplastic disease * Are unwilling or unable to comply with a rehabilitation program or would fail to return for the postoperative follow-up visits prescribed by the protocol * Are skeletally immature. * Have a known allergic reaction to implant metals, polyethylene or a tissue reaction to corrosion or wear products * Have other conditions such as central nervous system disturbances, alcohol or drug addiction, etc. that may make effective evaluation of the joint replacement difficult or impossible * Are currently participating in another clinical study * Are taking \> 10mg/day corticosteroids (e.g. prednisone) excluding inhalers, within 3 months prior to surgery * Are currently involved in any personal injury litigation, medical legal or worker's compensation claims.