An implantable medical device for implantation in a mammal joint having at least two contacting surfaces is provided. The medical device comprises; an artificial contacting surface adapted to replace at least the surface of at least one of the mammal's joint contacting surfaces, wherein the artificial contacting surface is adapted to be lubricated, when implanted in said joint. Furthermore the medical device comprises at least one inlet adapted to receive a lubricating fluid from a reservoir, at least one channel at least partly integrated in the artificial contacting surface in connection with the at least one inlet for distributing the lubricating fluid to the surface of the artificial contacting surface. The medical device could be adapted to be operable by an operation device to receive the distributed lubricated fluid from a reservoir.