AETOS Shoulder System for Shoulder Osteoarthritis

Inclusion Criteria: Patients must meet all the following criteria to be included in the study: 1. Patient is at least 18 years of age at the time of consent and skeletally mature. 2. Patient is undergoing a primary elective anatomic or reverse shoulder replacement surgery for one of the following indications: * Rheumatoid arthritis, and/or * Traumatic arthritis (Post Traumatic arthritis), and/or * Non-inflammatory degenerative joint disease, and/or * Correction of functional deformity. 3. Patient is willing and able to accommodate all study-related procedures and visits detailed in the protocol \& cooperate in the standard of care post-operative therapy. 4. Patient is geographically stable and willing to return to the study site for all follow-up visits. 5. Patient has been adequately informed of risks and requirements of the study and is willing and able to provide informed consent for participation. \- Exclusion Criteria: Patients who meet any of the following criteria will not qualify for participation in the trial: 1. Patient has a contraindication to AETOS. 2. Patient is undergoing a revision shoulder replacement surgery including total or partial arthroplasty. 3. Patient is indicated for a Hemiarthroplasty. 4. Patient has traumatic injury or a fracture. 5. Patient has uncontrolled diabetes with a hemoglobin A1C of 7.5 or greater. 6. Patient has comorbidities/conditions that preclude proper healing/fixation of the implant. 7. Patient has poor quality or insufficient bone stock to support the implant. 8. Patient has poor bone quality where there could be considerable migration of the implant and/or a chance of fracture. 9. Patient has rapid joint destruction, marked bone loss or bone resorption (e.g., severe osteoporosis). 10. Patient has osteomalacia. 11. Patient has muscular, neurologic, or vascular deficiencies that may compromise the outcome of the shoulder replacement surgery. 12. Patient has a known sensitivity, allergic reaction, and/or known allergies to one or more of the implanted materials. 13. Patient has a distant foci of infection which may spread to the implant site, active local or systemic infection, sepsis, or osteomyelitis. 14. Patient has an elevation of sedimentation rate, elevation of WBC count, or marked shift in WBC differential count unexplained by other disease. 15. If reverse shoulder arthroplasty, patient has a non-functional deltoid or external rotator muscles. 16. If reverse shoulder arthroplasty, patient has a significant injury to the upper brachial plexus. 17. If reverse shoulder arthroplasty, patient has paralysis of the axillary nerve. 18. Patient is uncooperative, has a neurologic disorder and is not capable of following directions, or is a vulnerable subject per ISO 14155 (i.e., individuals who are unable to fully understand all aspects of the investigation that are relevant to the decision to participate, or who could be manipulated or unduly influenced as a result of a compromised position, expectation of benefits or fear of retaliatory response). 19. Patient is pregnant or plans to become pregnant during the follow-up period. 20. Patient has a Body Mass Index (BMI) of \>35kg/m2 or a BMI that may compromise the outcome of the shoulder replacement surgery. 21. Patient has anticipated activities which would impose high stresses on the implant and its fixation or has a high likelihood of a fall. 22. Patient is a known smoker, vaper, alcohol abuser, or drug abuser within 180 days of consent. 23. Patient has participated previously in this clinical trial and was withdrawn. 24. Patient is participating in another device or drug trial or observational competitive study.