Sidus(TM) Post Market Clinical Follow-up (PMCF) Study

Inclusion Criteria: * Patient is 18 to 80 years of age, inclusive. * The patient is skeletally mature. * Patient is suffering from severe shoulder pain and disability requiring unilateral or bilateral HSA or TSA based on physical exam and medical history. * Patient has failed conservative treatment. * Patient meets at least one of the following indications: Osteoarthritis, Posttraumatic arthrosis, Rheumatoid arthritis without humeral metaphyseal defects, Focal avascular necrosis of the humeral head, Previous surgeries of the shoulder that do no compromise the fixation. * Patient is willing and able to cooperate in the required post-operative therapy. * Patient is willing and able to complete scheduled follow-up evaluations as described in the Informed Consent. * Patient has participated in the Informed Consent process and has signed the Ethics Committee approved "Informed Consent". Exclusion Criteria: * Patient is unwilling or unable to give consent or to comply with the follow-up program. * Patients who have any condition which would in the judgement of the Investigator place the patient at undue risk or interfere with the study. Any patient who is institutionalized, or is an known drug abuser, a known alcoholic or anyone who cannot understand what is required of them. * Patient is known to be pregnant or breastfeeding. * Patient meets at least one of the contraindications: Soft or inadequate humeral bone (including osteoporosis and extensive avascular necrosis or rheumat…