Psoriatic arthritis (PsA) mutilans is a rare form of PsA that is extremely destructive, mimicking a charcot-like arthropathy. To date, the mutilans form of PsA has been described in the knee, spine, and elbow, but, to the best of our knowledge, this is the first report of this condition in the shoulder. This is a case presentation of a 59-year-old male with PsA demonstrating near complete and rapid disappearance of his right proximal humerus over the span of a few weeks. After a thorough diagnostic work-up, the patient was treated definitively with a hemiarthroplasty with improvement in his pain and range of motion (ROM) and satisfactory functional outcomes. Currently, there have not been any published recommendations for the diagnosis and management of arthritis mutilans of the shoulder, and we review our diagnostic and treatment strategy.