Tissue fixation device
A suture anchor is formed of a material which absorbs body liquid when exposed to body liquid. The anchor may be at least partially formed of a material having a strong affinity for body liquids. This enables the anchor to absorb body liquid and expand upon being inserted into a patient's body. At least one embodiment of the suture anchor has portions formed of a relatively hard material which does not absorb body liquids and is pressed against body tissue by the material which absorbs body liquid to mechanically interlock the suture anchor and the body tissue. The anchor may be at least partially formed of a cellular material. The cells expand to absorb body liquid. At least one embodiment of the anchor has a pointed leading end portion to form an opening in an imperforate surface on body tissue. The configuration of the anchor may be changed by tensioning the suture while the anchor is disposed in body tissue.
1 . A method of securing a suture comprising:
providing a suture anchor having a generally tubular configuration and a passage extending axially therethrough;
positioning a portion of a suture within the passage of the anchor;
inserting the anchor into body tissue with the suture extending from the anchor;
expanding a portion of the suture anchor radially outward to lock the anchor within the body tissue; and
tensioning the suture.
2 . The method of claim 1 , further including creating a recess in the body tissue and wherein inserting the anchor includes inserting the anchor within the recess.
3 . The method of claim 2 , wherein the body tissue is bone.
4 . The method of claim 3 , wherein the recess is created by drilling the bone.
5 . The method of claim 4 , wherein the anchor has an initial orientation during the insertion step and maintains the initial orientation during the expansion step.
6 . The method of claim 5 , further including the step of securing soft tissue relative to the bone.
7 . The method of claim 1 , wherein the suture anchor has first and second configurations, the anchor having the first configuration prior to expansion and the second configuration after expansion.
8 . The method of claim 7 , wherein the first configuration of the anchor is smaller in diameter than the second configuration.
9 . The method of claim 8 , wherein the second configuration of the suture anchor locks the anchor into the body tissue.
10 . The method of claim 1 , wherein expanding the anchor includes increasing a cross sectional area of the anchor as viewed in a plane extending perpendicular to the longitudinal axis of the anchor.
11 . The method of claim 10 , wherein the increased cross sectional area of the suture anchor locks the anchor into the body tissue.
12 . The method of claim 1 , wherein the anchor is made of a polymeric material.
13 . The method of claim 1 , wherein the anchor includes both polymeric and ceramic materials.
14 . The method of claim 13 , wherein the polymeric material is a resorbable polymer.
15 . A method of securing a suture comprising:
providing a suture anchor having a generally tubular configuration and a passage extending axially therethrough;
positioning a portion of a suture within the passage of the anchor;
creating a recess in bone;
inserting the anchor into the recess with the suture extending from the anchor;
increasing an cross sectional diameter of a portion of the suture anchor to lock the anchor within the bone; and
tensioning the suture.
16 . The method of claim 15 , wherein the recess has a substantially cylindrical shape.
17 . The method of claim 16 , wherein the anchor has an initial orientation during the insertion step and maintains the initial orientation thereafter.
18 . The method of claim 17 , further including the step of securing soft tissue relative to the bone with the suture.