A method for controlling properties of a medical implant includes locating the medical implant in an interspinous area between two spinal processes of a person. The medical implant is coupled to a container via a conduit. A fluid is received in an interior of the container in fluid communication with the conduit. The fluid flows from the container toward the implant having an interior configured to receive the fluid. A pressure sensor is coupled to the interior of the container and/or an interior of the conduit. An internal pressure is determined of the interior of the interior of the container and/or the interior of the conduit by the sensor. The flow of the fluid is regulated to the interior of the implant to regulate a volume of the implant based on the internal pressure and a medical condition of the person.