A cylindrical, fibrous, porous joint spacer is provided, having excellent properties, flexibility of formation, and operability, which is intended to be implanted as a prosthesis between bones to be joined together. The joint spacer of the present invention can be formed from a strip of fabric, which is comprised of bioabsorbable fibers and made by a knitting, weaving, non-woven or other technique. The fabric is typically relatively narrow (e.g. 1 to 10 mm wide) and thin (e.g. 0.1 to 1.0 mm thick), depending on the intended application of the prosthetic device to be formed from the fabric. The joint spacer of the present invention is made by wrapping said fabric to yield a cylindrical body; and fixing the free end of the fabric to the surface of the cylindrical body so formed. The joint spacer of the present invention can be implanted in conjunction with one or more fixation parts, to hold the joint spacer in place between the bones to be joined.