Expandable prosthetic devices used for treating a variety of conditions, including rotator cuff injuries, broken and/or depressed bone fractures, infection and/or inflammation in the body. In one embodiment, a prosthesis includes an implant having a pressure regulating valve. The implant is capable of being positioned between a first tissue and an opposing second tissue in a void space and of deforming under pressure in response to articulation of a joint. The pressure regulating valve is configured to open based on a predetermined pressure in the implant.
