This invention relates in general to a bioabsorbable surgical tissue fixation
implant (nail) and, more particularly to an
implant for the fixation of
soft tissue to bone. In one embodiment of the invention, the fixation
implant generally includes at least one shaft configured to securely fit into a hole formed in bone. The shaft is of sufficient length relative to the interior
diameter of the hole and, in some preferred embodiments, has locking protuberances, like threads, ridges, or barbs, that
resist removal of the shaft from the hole in the bone when different types of forces, such as tensile or bending forces, are applied to the implant. The shaft is generally cylindrical in shape, however, in various embodiments of the invention, different cross-sections could be used. In a preferred embodiment of the present invention, the implant has a flattened and bent end portion emerging from only one side of the shaft. At the other side of the implant the outer surface of the shaft and the emerging end portion form a
smooth surface, without any projections. This
smooth surface at the end of the implant prevents
irritation of the surrounding tissue. The end portion has a
mating surface configured to grip a portion of the
soft tissue surrounding the hole between the bone and the
mating surface. The longitudinal axis of the shaft is oriented at an angle of less than 90 degrees relative to the
mating surface. In this fashion, the implant anchors
soft tissue, such as
rotator cuff tissue, to bone.