"Science, as well as science fiction, has long dreamed of replacing lost
or damaged (or simply inadequate) human limbs with bionic prosthetics.
Progress has been slow to date, as it's notoriously hard to get the
human body to accept non-biological materials as 'part of the
furniture'. A breakthrough at University College, London may change all
that though - a way of securing a titanium rod into human bone, and having the skin heal and mesh around it without bleeding or infections."