Implant
An implant is provided, and the implant includes a body, a limiting portion and a filling portion. The body has a first end portion, a second end portion opposite to the first end portion, and a middle portion disposed between the first end portion and the second end portion. The limiting portion includes a first solid structure and is located at the first end portion. The filling part includes an elastic structure and is located from the middle portion to the second end portion. A diameter of the first end portion of the body is greater than a diameter of the middle portion, and a diameter of the second end portion is greater than the diameter of the middle portion.
1 . An implant for repairing an intervertebral annulus fibrosus, comprising:
a body having a first end portion, a second end portion, and a middle portion disposed between the first end portion and the second end portion;
a limiting portion comprising a first solid structure and being located at the first end portion; and
a filling portion comprising an elastic structure and a porous structure in the elastic structure, and being located between the middle portion and the second end portion, wherein the elastic structure comprises:
a first region adjacent to the first end portion and having a first porosity;
a second region adjacent to the second end portion and having a second porosity; and
a third region disposed between the first region and the second region and having a third porosity,
wherein the third porosity of the third region is greater than the first porosity of the first region,
wherein a ratio of the first solid structure to the elastic structure is in a range of from 1:1 to 1:8; and
wherein a diameter of the first end portion of the body is greater than a diameter of the middle portion, and a diameter of the second end portion is greater than the diameter of the middle portion.
2 . The implant of claim 1 , wherein the porous structure comprises a hole structure, a regular grid structure, an irregular grid structure, or a combination thereof.
3 . The implant of claim 2 , wherein the porous structure is a gradient porous structure.
4 . The implant of claim 1 , wherein pore sizes of a plurality of pores in the porous structure are in a range of from 200 micrometers to 600 micrometers.
5 . The implant of claim 1 , further comprising:
a channel disposed within the body of the implant and extending through the body.
6 . The implant of claim 1 , wherein the third porosity is greater than both the first porosity and the second porosity.
7 . The implant of claim 1 , wherein the filling portion further comprises a hollow structure.
8 . The implant of claim 7 , wherein the hollow structure comprises a fence structure, a regular grid structure, or a combination thereof.
9 . The implant of claim 1 , wherein an outer surface of a junction between the first end portion and the middle portion of the implant comprises an anchoring structure, and the anchoring structure comprises at least one barb unit, and
the at least one barb unit comprises a fixed end and a free end opposite to the fixed end, and the fixed end is connected to the outer surface of the junction, and the free end extends toward a direction of the middle portion of the implant.
10 . The implant of claim 1 , wherein the filling portion located at the second end portion comprises a second solid structure.
11 . The implant of claim 1 , wherein the filling portion further comprises:
a retracted portion having a first end and a second end opposite to the first end, wherein the first end is connected to the limiting portion, and wherein the retracted portion has a minimum diameter, the limiting portion has a first maximum diameter, and the first maximum diameter is greater than the minimum diameter; and
an opening portion connected to the second end of the retracted portion, wherein the opening portion has a second maximum diameter, and the second maximum diameter is greater than the minimum diameter.
12 . The implant of claim 11 , wherein the limiting portion has a disc-shaped structure.
13 . The implant of claim 11 , wherein the opening portion comprises an against unit, and the against unit is disposed around an outer surface of the retracted portion and extends to an outer surface of the opening portion, and
wherein the against unit comprises a connecting rod portion and a limiting against portion integrally formed with the connecting rod portion.
14 . The implant of claim 13 , wherein:
the connecting rod portion is in contact with the outer surface of the opening portion; or
the limiting against portion and the outer surface of the retracted portion are spaced apart from each other.
15 . The implant of claim 14 , wherein the retracted portion further comprises:
a third solid structure adjacent to the limiting portion; and
a fourth solid structure adjacent to the limiting against portion, wherein a diameter of the fourth solid structure is greater than the minimum diameter of the retracted portion.
16 . The implant of claim 15 , wherein the limiting against portion is against a surface of the fourth solid structure.
17 . The implant of claim 11 , wherein the opening portion comprises at least two arms, and the at least two arms are laterally collapsed or expanded relative to a central axis of the opening portion.
18 . The implant of claim 17 , wherein the at least two arms are equidistantly or non-equidistantly disposed around an outer periphery of the opening portion of the filling portion.