Subchondral bone defect treatment
Apparatus and methods are described for treating a subchondral bone defect within a bone of a subject that is adjacent to a joint. A hole is created within the bone extending from a first cortex of the bone to a second cortex of the bone. An implantable device is inserted into the hole such that the implantable device extends from the first cortex of the bone through the subchondral defect and to the second cortex of the bone, the implantable device having a flexural modulus of more than 10 GPa and being resorbable. The implantable device is left deployed within the bone, such that the implantable device becomes resorbed into the bone. Other applications are also described.
1 . A method for treating a subchondral bone defect within a bone of a subject that is adjacent to a joint, the method comprising:
creating a hole within the bone extending from a first cortex of the bone to a second cortex of the bone;
inserting an implantable device into the hole such that the implantable device extends from the first cortex of the bone through the subchondral defect and to the second cortex of the bone, the implantable device having a flexural modulus of more than 10 GPa and being resorbable; and
leaving the implantable device deployed within the bone, such that the implantable device becomes resorbed into the bone.
2 . The method according to claim 1 , wherein inserting the implantable device into the hole comprises inserting the implantable device such that one side of the implantable device is anchored to a peripheral cortex, to thereby create a cantilever beam support.
3 . The method according to claim 1 , wherein inserting the implantable device into the hole comprises inserting, into the hole, an implantable device, selected from the group consisting of: a rod, a bar, a screw, a pin, and a nail.
4 . The method according to claim 1 , wherein a span of a cross-sectional shape defined by the implantable device is 2 mm-10 mm.
5 . The method according to claim 1 , wherein the bone includes a femur of the subject, and wherein inserting the implantable device into the hole comprises inserting the implantable device such that the implantable device extends from a lateral or medial cortex of the bone, through the subchondral defect, and to a condylar cortex.
6 . The method according to claim 5 , wherein inserting the implantable device into the hole comprises inserting the implantable device such that the implantable device is less than 30 mm above a subchondral plate.
7 . The method according to claim 1 , wherein the bone includes a tibia of the subject, and wherein inserting the implantable device into the hole comprises inserting the implantable device such that the implantable device extends from a lateral cortex of the bone, through the subchondral defect, and to a medial cortex.
8 . The method according to claim 7 , wherein inserting the implantable device into the hole comprises inserting the implantable device such that the implantable device is less than 30 mm below a subchondral plate.
9 . The method according to claim 1 , wherein the implantable device has a flexural modulus of 10-30 GPa.
10 . The method according to claim 1 , wherein the implantable device has an initial length of 50-150 mm.
11 . The method according to claim 1 , wherein the implantable device has a polygonal cross-sectional shape.
12 . The method according to claim 1 , wherein the implantable device is composed of at least 30% mineral weight-by-weight.
13 . The method according to claim 12 , wherein the implantable device comprises reinforcing mineral fibers.
14 . The method according to claim 13 , wherein the reinforcing mineral fibers comprise continuous fibers having lengths of 30-150 mm.
15 . The method according to claim 14 , wherein inserting the device into the hole comprises inserting the device into the hole such that a majority of the reinforcing fibers are aligned substantially in parallel to a surface of the joint.
16 . The method according to claim 14 , wherein inserting the device into the hole comprises inserting the device into the hole such that a majority of the reinforcing fibers pass through at least one of the first and second cortexes.
17 . The method according to claim 16 , wherein inserting the device into the hole comprises inserting the device into the hole such that a majority of the reinforcing fibers pass through both of the first and second cortexes.
18 . The method according to claim 1 , wherein the implantable device defines an implantable device body and protrusions from the implantable device body, the protrusions being selected from the group consisting of: threads, ribs, and teeth.
19 . The method according to claim 1 , wherein the implantable device is hollow and defines a lumen therethrough.
20 . An apparatus for treating a subchondral bone defect within a bone of a subject that is adjacent to a joint, the apparatus comprising:
an implantable device configured to be inserted into a hole within the bone, such that the implantable device extends from a first cortex of the bone, through the subchondral defect, and to a second cortex of the bone,
the implantable device having a flexural modulus of more than 10 GPa and being resorbable, and
the implantable device comprising an implantable device body and protrusions from the implantable device body, the protrusions being selected from the group consisting of: threads, ribs, and teeth.