Osteoarthritis is the most common condition that leads to shoulder replacement. This type of arthritis develops over the years as a result of joint wear-and-tear. The cushioning layer of cartilage on the ends of your bones deteriorates and wears down, gradually exposing the bone and without protection the bones rub together and create friction. The result is chronic joint pain, stiffness, and loss of function..Some other reasons why you might need a shoulder replacement include:.☑️Rheumatoid arthritis (RA) and post-traumatic arthritis.☑️Failed previous shoulder replacement surgery.☑️Severe fractures.☑️Avascular necrosis (osteonecrosis).☑️Rotator cuff tear arthropathy