Urethral artificial sphincter with bistable actuation system

An artificial sphincter comprising:

• a container having a longitudinal axis, said container configured to be connected to a wall of a patient's urethra;
• a valve unit arranged within said container, and configured to reversibly move between:
• a release configuration, in which said valve unit is arranged to allow a passage of urine through said artificial sphincter, and
• a block configuration, in which said valve unit is arranged to prevent said passage of urine through said artificial sphincter;
• a stabilization magnet having poles arranged along a first magnetic axis, said stabilization magnet arranged integral to said container with said first magnetic axis parallel to said longitudinal axis,
• an actuation magnet having poles arranged along a second magnetic axis, parallel to said longitudinal axis, wherein said actuation magnet:
• is slidably arranged within said container, in order to change its own distance from said stabilization magnet along said longitudinal axis and to responsively change the magnetic force between said actuation magnet and said stabilization magnet;
• and
• is connected to said valve unit in such a way that a translation movement of said actuation magnet under the effect of an external maneuver magnetic field, causes said valve unit to move between said release configuration and said block configuration,
• a resilient element having a first end integral to said container and a second end, opposite to said first end, connected to said actuation magnet, so that said actuation magnet receives a resilient force responsive to said distance along said container,
• wherein said resilient element, said actuation magnet and said stabilization magnet are arranged in such a way that:
• said magnetic force has a direction opposite to said resilient force;
• said
• magnetic force has an intensity higher than said resilient force when said actuation magnet is distanced less than a predetermined equilibrium distance (d*) from said stabilization magnet;
• and
• said magnetic force has an intensity lower than said resilient force when said actuation magnet is distanced more than said equilibrium distance from said stabilization magnet,
• such that, if said actuation magnet is distanced less/more than said equilibrium distance, respectively, with respect to said stabilization magnet, said actuation magnet maintains/brings said valve unit in said release/block configuration.