Abstract: A surgically implantable device (1,10) made of a single piece of silicone, for joining phalanxes, metacarpus-phalanx or metatarsus-phalanx bones of the hand or foot in arthroplasty surgery, includes an enlarged central portion (2) formed by a thickened portion (5) having a rounded profile and provided with a canal (6) extending transversally in which a depression (7) is centrally formed, and by two elongated stem portions (3,4) which extend from the enlarged central portion (2), one opposed to the other. The device (1,10) is coated completely with at least one layer of turbostratic pyrolytic carbon less than or equal to 10 microns thick obtained by physical vapour deposition (PVD).