different variations of implants, and to date there is no consensus on which design is superior, although several studies have demonstrated some benefits to certain combinations. One such modern reverse shoulder implant system is the AltiVate Reverse. More information on this system can be found on the DJO website. History Traditional shoulder replacement (known as anatomic shoulder replacement) was developed to treat glenohumeral arthritis and consists of resurfacing the native humeral head and glenoid to create smooth articular surfaces to provide pain relief and improved range of motion. Variations of this procedure have been performed as early as 1883. While most patients can achieve substantial clinical improvement using this approach, those with large rotator cuff tears have consistently demonstrated poor outcomes due to loss of the stability provided by these muscles. In 1972, U.S. orthopedic surgeon Charles S. Neer designed a fixed-fulcrum shoulder replacement in which he reversed the ball and socket geometry. Unfortunately, his design resulted in several early failures, leading him to abandon this concept. Multiple other surgeons throughout the world subsequently developed reversed ball and socket implants, and while some achieved reasonably good results, the concept never gained significant traction until French surgeon Paul Grammont developed his “Trompette” prosthesis in 1985. This was further modified into the Delta III prosthesis in 1991. As Grammont's reverse ball and socket prosthesis gained popularity and began demonstrating reliable outcomes, he subsequently developed what would be known as the “Grammont Principles”, which were a set of rules that explained why his prosthesis was effective and why other reverse ball and socket designs failed. In 1998, U.S. orthopedic surgeon Mark Frankle began designing a reverse ball and socket prosthesis that did not adhere to the traditional Grammont Principles. He began patenting this device, the RSP (Reverse Shoulder Prosthesis), in 2002. Many doubted the effectiveness of his design and suggested that it would lead to higher failure rates, creating significant controversy and debate within the orthopedic community. After validating his theories with rigorous scientific studies and making several key modifications to his design, Frankle ultimately developed an implant that was able to address the shortcomings of the Grammont-style prostheses while also showing excellent survivorship. Multiple studies have since gone on to demonstrate the advantages of his design principles, and many of the modern generation reverse shoulder implants have mirrored them. With good outcome in Rotator cuff arthropathy, the indications for performing reverse shoulder