METHODS OF MAKING SUTURE NEEDLES WITH LOCALIZED REGIONS FOR BENDING
20200268379 ยท 2020-08-27
Inventors
Cpc classification
B21G1/00
PERFORMING OPERATIONS; TRANSPORTING
B21G1/006
PERFORMING OPERATIONS; TRANSPORTING
International classification
A61B17/06
HUMAN NECESSITIES
Abstract
A method of making a suture needle having a bendable region includes obtaining a suture needle made of a martensitic alloy having an austenitic transition temperature. The suture needle has a proximal section, a distal section with a sharpened tip, and a bendable region located between the proximal and distal sections. The method includes heating the suture needle to a first temperature that is greater than the austenitic transition temperature of the martensitic alloy and quenching the suture needle to room temperature to harden the martensitic alloy. After heating and quenching, the bendable region of the suture needle is heated locally to a second temperature that is above 800 degrees Celsius, but below the austenitic transition temperature of the martensitic alloy so that the bendable region is softened and made more flexible relative to the proximal and distal sections of the suture needle. The locally heating of the bendable region is by electrical resistance heating, laser heating, induction heating, flame heating, or hot gas heating. The suture needle is tempered to improve ductility.
Claims
1. A method of making a suture needle having a bendable region comprising: obtaining a suture needle made of a martensitic alloy having an austenitic transition temperature, said suture needle having a proximal section, a distal section with a sharpened tip, and a bendable region located between said proximal and distal sections; heating said suture needle to a first temperature that is greater than the austenitic transition temperature of said martensitic alloy and quenching said suture needle to room temperature to harden said martensitic alloy; after the heating and quenching steps, locally heating said bendable region of said suture needle to a second temperature that is above 800 degrees Celsius but below the austenitic transition temperature of said martensitic alloy so that said bendable region is softened and made more flexible relative to said proximal and distal sections of said suture needle.
2. The method as claimed in claim 1, further comprising forming said suture needle into a seagull shaped configuration in which said proximal section of said suture needle defines a proximal arc, said distal section of said suture needle defines a distal arc, and said bendable region of said elongated body defines a V-shaped section that interconnects inner ends of said proximal and distal arcs, wherein said proximal arc, said distal arc, and said V-shaped section lie in a common plane.
3. The method as claimed in claim 1, further comprising forming said suture needle into a folded configuration in which said proximal section of said suture needle lies in a first plane, said distal section of said suture needle lies in a second plane that is different than the first plane, and said bendable region of said suture needle interconnects inner ends of said proximal and distal sections of said suture needle, wherein with said sharpened tip of said distal section of said suture needle is adjacent a proximal-most end of said proximal section of said suture needle.
4. The method as claimed in claim 1, wherein the first temperature that is above the austenitic transition temperature is between about 950-1,040 degrees Celsius.
5. The method as claimed in claim 1, wherein the second temperature for locally heating said bendable region is between about 800-920 degrees Celsius.
6. The method as claimed in claim 1, wherein the quenching step comprises using a gas or a liquid for cooling said suture needle.
7. The method as claimed in claim 6, wherein the cooling step comprises rapidly cooling said suture needle at a cooling rate that is greater than 100 degrees Celsius per minute.
8. The method as claimed in claim 1, wherein the locally heating step is selected from the group of heating methodologies consisting of electrical resistance heating, laser heating, induction heating, flame heating, and hot gas heating.
9. The method as claimed in claim 1, further comprising tempering said suture needle.
10. The method as claimed in claim 1, wherein the tempering step comprises heating said suture needle to a temperature of about 150-430 degrees Celsius for increasing ductility of said suture needle.
11. The method as claimed in claim 1, wherein the obtaining step comprises curving at least one of said proximal and distal sections of said suture needle.
12. The method as claimed in claim 1, wherein said proximal and distal sections of said suture needle body define a first outer wire diameter and said bendable region of said suture needle defines a second outer wire diameter that is smaller than the first outer wire diameter of said respective proximal and distal sections.
13. The method as claimed in claim 1, wherein said bendable region of said suture needle comprises one or more flat surfaces, and wherein said bendable region of said suture needle is thinner than said proximal and distal sections of said suture needle.
14. A method of making a suture needle having a bendable region comprising: obtaining a wire made of a martensitic alloy have an austenitic transition temperature; heating said wire to a first temperature that is greater than 800 degrees Celsius and less than the austenitic transition temperature to soften said wire; after the heating step, cooling said wire to room temperature; after the cooling step, using a section of said cooled wire for forming a suture needle having a proximal section, a distal section with a sharpened tip, and a bendable region located between said proximal and distal sections; after forming said suture needle, locally heating said proximal and distal sections of said suture needle to a second temperature that is above the austenitic transition temperature of said martensitic alloy for hardening said proximal and distal sections of said suture needle while maintaining said bendable region of said suture needle at a third temperature that is below the austenitic transition temperature of said martensitic alloy so that said bendable region is softer and more flexible than said proximal and distal sections of said suture needle; after the locally heating step, quenching said suture needle to room temperature.
15. The method as claimed in claim 14, wherein the first temperature is between about 800-920 degrees Celsius, and wherein the second temperature is between about 950-1,040 degrees Celsius.
16. The method as claimed in claim 14, further comprising after quenching said suture needle, tempering said suture needle.
17. The method as claimed in claim 14, wherein the locally heating step is selected from the group of heating methodologies consisting of electrical resistance heating, laser heating, induction heating, and flame heating.
18. The method as claimed in claim 14, wherein the forming a suture needle step comprises shaping said suture needle into a seagull shaped configuration or a folded configuration.
19. The method as claimed in claim 14, wherein said proximal and distal sections of said suture needle body define a first outer wire diameter and said bendable region of said suture needle defines a second outer wire diameter that is smaller than the first outer wire diameter of said respective proximal and distal sections.
20. A method of making a suture needle having a bendable region comprising: drawing a wire made of a martensitic-aged (mar-aged) alloy to obtain a wire strand; heating said wire strand to a first temperature of between about 450-700 degrees Celsius to harden said wire strand; using a section of said hardened wire strand for forming a suture needle having a proximal section, a distal section with a sharpened tip, and a bendable region located between said proximal and distal sections; locally heating said bendable region of said suture needle to a second temperature that is greater than 700 degrees Celsius while maintaining said proximal and distal sections of said suture needle at a third temperature that is below 700 degrees Celsius so that said bendable region of said suture needle is softer and more flexible than said proximal and distal sections of said suture needle.
21. The method as claimed in claim 20, wherein the locally heating step is selected from the group of heating methodologies consisting of electrical resistance heating, laser heating, induction heating, flame heating, and hot gas heating.
22. The method as claimed in claim 20, wherein said wire strand comprises said martensitic-aged alloy, and wherein the heating said wire strand to the first temperature step comprises precipitation heat treating said wire strand.
23. The method as claimed in claim 20, wherein said proximal and distal sections of said suture needle body define a first outer wire diameter and said bendable region of said suture needle defines a second outer wire diameter that is smaller than the first outer wire diameter of said respective proximal and distal sections.
24. A method of making a suture needle having a bendable region comprising: obtaining a wire made of a martensitic-aged (mar-aged) alloy; using a section of said wire for forming a suture needle having a proximal section, a distal section with a sharpened tip, and a bendable region located between said proximal and distal sections; locally heating said bendable region of said suture needle to a first temperature that is greater than 700 degrees Celsius while maintaining said proximal and distal sections of said suture needle at a temperature that is below 700 degrees Celsius so that said bendable region of said suture needle is softer and more flexible than said proximal and distal sections of said suture needle; after the locally heating step, cooling said suture needle to room temperature; after the cooling step, heating said proximal and distal sections of said suture needle to a second temperature of about 450-700 degrees Celsius while maintaining said bendable region of said suture needle below the second temperature.
25. The method as claimed in claim 24, wherein said mar-aged alloy is selected from the group consisting of 455SS and a stainless steel sold under the trademark ETHALLOY having a composition of about 73% iron, 12% chrome, 10% nickel 10%, 3% molybdenum 3%, and 2% titanium.
26. The method as claimed in claim 24, wherein the locally heating step is selected from the group of heating methodologies consisting of resistive heating, laser heating, induction heating, flame heating, and hot gas heating.
27. The method as claimed in claim 24, further comprising clamping said bendable region with a heat sink during the heating said proximal and distal sections of said suture needle to the second temperature.
28. A method of making a suture needle having a bendable region comprising: drawing a wire made of an austenitic alloy to obtain a wire strand; using a section of said wire strand for forming a suture needle having a proximal section, a distal section with a sharpened tip, and a bendable region located between said proximal and distal sections; locally heating said bendable region of said suture needle to a temperature that is greater than 700 degrees Celsius while maintaining said proximal and distal sections of said suture needle at a second temperature that is below 700 degrees Celsius so that said bendable region of said suture needle is softer and more flexible than said proximal and distal sections of said suture needle.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0067] Referring to
[0068] In one embodiment, the bendable region may be midway between proximal and distal ends of the suture needle. In one embodiment, the bendable region may be closer to the distal end than the proximal end of the suture needle. In one embodiment, the bendable region may be closer to the proximal end than the distal end of the suture needle.
[0069] In one embodiment, the bendable region may be formed by reducing a cross-sectional wire diameter of the suture needle within the bendable so that the bendable region is thinner than the proximal and distal sections of the suture needle. In one embodiment, the bendable region may be formed by making the bendable region of a material that is softer and/or more flexible than the material that is used to make the proximal and distal sections of the needle. In one embodiment, the bendable region may be treated with heat to soften the material within the bendable region to make it more flexible than the proximal and distal sections of the suture needle.
[0070] In one embodiment, the bendable region 110 may include a first flat surface 112 located on a top side of the elongated body 102 of the suture needle 100 and a second flat surface 114 located on an underside of the elongated body 102 of the suture needle 100.
[0071] In one embodiment, the bendable region 110 preferably has a smaller outer wire diameter than the outer wire diameter of the proximal and distal sections 104, 106 of the suture needle 100, which are located on opposite sides of the bendable region 110. In one embodiment, the proximal and distal sections 104, 106 of the elongated body 102 preferably have respective outer wire diameters OD.sub.1 that are greater than the outer wire diameter OD.sub.2 of the bendable region 110, which is defined by the first and second flat surfaces 112, 114.
[0072] In one embodiment, the proximal and distal sections 104, 106 of the elongated body 102 of the suture needle 100 preferably define a first outer wire diameter and the bendable region 110 of the suture needle 100 defines a second outer wire diameter that is smaller than the first outer wire diameter of the respective proximal and distal sections. In one embodiment, the bendable region 110 of the suture needle 100 preferably includes one or more flat surfaces, whereby the bendable region 110 of the suture needle 100 is thinner than the proximal and distal sections 104, 106 of the suture needle 100.
[0073] In one embodiment, the bendable region 110 has a length L.sub.1 (
[0074] Referring to
[0075] In one embodiment, when the elongated body 102 of the suture needle 100 has been bent into the seagull shape configuration of
[0076] Providing a suture needle 100 with a bendable region (i.e., a region that is more flexible or bendable than adjacent sections of the needle) preferably enables surgical personnel to reduce the overall height and/or dimension of the suture needle so that it may be passed through smaller trocars, such as those that are typically used in minimally invasive surgeries (MIS)(e.g., 5 mm trocars).
[0077] In one embodiment, a suture needle may have a bendable region for bending or folding the needle to reduce its outer dimension or profile for passing the suture needle through a trocar as disclosed in commonly assigned U.S. patent application Ser. No. ______ (Attorney Docket No. ETH6024USNP1-PEZ#167572 and #167573), the disclosure of which is hereby incorporated by reference herein. In one embodiment, a suture needle may have a thinner section, such as by forming flattened surfaces one or more outer surfaces of an elongated body of the suture needle. In one embodiment, the suture needle may be heat treated to produce a suture needle that is relatively more bendable in one or more locations, while the remainder of the needle is made to exhibit the exceptional strength, stiffness, and hardness expected of a typical suture needle (e.g., a stainless steel needle). In one embodiment, the bendable region of a suture needle may include a composition of a superelastic material (e.g., Nitinol), while the remainder of the suture needle is made of a material (e.g., stainless steel) that is relatively stronger, stiffer, and harder than the superelastic material found in the bendable region.
[0078] In one embodiment, a preferred method of making a suture needle with a bendable region may differ depending upon the particular type of alloy that is used for making the suture needle.
[0079] In one embodiment, suture needles having bendable regions that are made of martensitic alloys are processed differently from martensitic-aged and austenitic stainless steel alloys commonly used in needle manufacturing. For example, martensitic alloys may contain carbon and/or nitrogen, such as 420 stainless steel, which hardens when cooled rapidly. As a result, needles made of martensitic alloys may be processed differently from needles made of martensitic-aged (mar-aged) or austenitic stainless steel alloys.
[0080] In one embodiment, a method of making a suture needle having a bendable region, such as the suture needle shown and described in
[0081] In one embodiment, the suture needle made of the martensitic alloy is heated to a first temperature that is greater than the austenitic transition temperature of the martensitic alloy. In one embodiment, the first temperature that is above the austenitic transition temperature is preferably between about 950-1,040 degrees Celsius.
[0082] In one embodiment, after heating the suture needle to the first temperature that is above the austenitic transition temperature, the suture needle is preferably quenched to room temperature to harden the martensitic alloy. In one embodiment, the quenching step may be accomplished by using a gas or a liquid for cooling the suture needle to room temperature. In one embodiment, cooling the suture needle to room temperature may include rapidly cooling the suture needle at a cooling rate that is greater than 100 degrees Celsius per minute.
[0083] In one embodiment, after the heating and quenching steps described above for hardening the suture needle, the bendable region of the suture needle is preferably heated to a second temperature that is above 800 degrees Celsius but below the austenitic transition temperature of the martensitic alloy so that the bendable region is softened and made more flexible relative to the proximal and distal sections of the suture needle that remain hardened from the initial heating and quenching steps described above.
[0084] In one embodiment, the second temperature used for locally heating the bendable region is preferably between about 800-920 degrees Celsius. In one embodiment, locally heating the bendable region may be accomplished using various heating methodologies including electrical resistance heating, laser heating, induction heating, flame heating, hot gas heating, and/or one or more combinations thereof.
[0085] In one embodiment, the suture needle may be formed and/or shaped into a suture needle having a seagull shaped configuration in which the proximal section of the suture needle defines a proximal arc, the distal section of the suture needle defines a distal arc, and the bendable region of the suture needle defines a V-shaped or U-shaped section that interconnects inner ends of the proximal and distal arcs of the respective proximal and distal sections of the suture needle. In one embodiment, the proximal arc, the distal arc, and the V-shaped or U-shaped section desirably lie in a common plane.
[0086] In one embodiment, the above-described heating, quenching, and locally heating steps for making the bendable region of the suture needle softer and more flexible and the proximal and distal sections of the suture needle relatively stronger, stiffer and harder than the bendable region may be performed the suture needle is formed into the seagull shaped configuration, while the suture needle is being formed into the seagull shaped configuration, or after the suture needle has been formed into the seagull shaped configuration.
[0087] In one embodiment, the suture needle may be formed and/or shaped into a suture needle having a folded configuration in which the proximal section of the suture needle lies in a first plane, the distal section of the suture needle lies in a second plane that is different than the first plane, and the bendable region of the suture needle interconnects inner ends of the proximal and distal sections of the suture needle, whereby the sharpened tip of the distal section of the suture needle is adjacent a proximal-most end of the proximal section of the suture needle.
[0088] In one embodiment, the above-described heating, quenching, and locally heating steps for making the bendable region of the suture needle softer and more flexible and the proximal and distal sections of the suture needle relatively stronger, stiffer and harder may be performed before the suture needle is formed into the folded configuration, while the suture needle is being formed into the folded configuration, or after the suture needle has been formed into the folded configuration.
[0089] In one embodiment, the suture needles may be shaped into the seagull shaped configuration, the folded configuration, or any other bendable shaped configuration using one or more curving mandrels or one or more bending presses (e.g., using a tooling similar to three point bending fixtures commonly used to bend test beams). Combinations of bending presses and curving mandrels may also be used for shaping the suture needles.
[0090] While the transformation resulting from the heat treatment increases the mechanical strength of the martensitic suture needle, it is accomplished with an accompanying decrease in ductility. In order to improve the ductility of heat treated suture needle, the martensitic suture needle may be subsequently tempered.
[0091] The methods and processes that are used for heat treating suture needles may be varied. In one embodiment, the heat treatment may be performed using a continuous belt furnace whereby the suture needles are fed through a hot zone at the reaction temperature. In this process, the temperature of the suture needles preferably increases to the reaction temperature in a hot zone. The suture needles are then passed into a cooler zone where the transformation takes place. This process may take place under a protective atmosphere of nitrogen, hydrogen or an inert gas.
[0092] The suture needles may also be batch processed in a furnace. This process may also take place in a protective atmosphere of nitrogen, hydrogen or an inert gas.
[0093] For both of the previously-mentioned processes, the suture needles are desirably tempered after the initial heat treatment step in a separate furnace at a lower temperature. The tempering process may be performed in air or under an atmosphere of nitrogen or inert gas.
[0094] In one embodiment, after the heating, quenching, and locally heating steps, the suture needle may be tempered for increasing the ductility of the suture needle. In one embodiment, the entire suture needle including the proximal and distal sections and the bendable region is tempered. In one embodiment, the proximal and distal sections of the suture needle are tempered and the bendable region is not tempered. In one embodiment, the suture needle may be tempered by heating the suture needle to a temperature of about 150-430 degrees Celsius.
[0095] Referring to
[0096] Referring to
[0097] In one embodiment, the bendable region 210 of the elongated body 202 is preferably defined by first and second flat surfaces 212, 214 (
[0098] In one embodiment, the length of the first and second flat surfaces 212, 214 that form the bendable region 210 of the suture needle 400 desirably define a length L.sub.2 that is equal to or greater than the outer diameter OD.sub.3 (
[0099] Referring to
[0100] Referring to
[0101] Referring to
[0102] In one embodiment, after the heating step, the wire is preferably cooled to room temperature. Referring to
[0103] In one embodiment, after forming the suture needle 200, the proximal and distal sections 204, 206 of the suture needle 200 may be locally heated to a second temperature that is above the austenitic transition temperature of the martensitic alloy for hardening the proximal and distal sections 204, 206 of the suture needle 200 while maintaining the bendable region 210 of the suture needle 200 at a temperature that is below the austenitic transition temperature of the martensitic alloy so that the bendable region 210 is softer and more flexible than the proximal and distal sections 204, 206 of the suture needle 200. In one embodiment, the second temperature that is above the austenitic transition temperature of the martensitic alloy is preferably between about 950-1,040 degrees Celsius. In one embodiment, the proximal and distal sections of the suture needle may be locally heated using various heating methodologies including but not limited to electrical resistance heating, laser heating, induction heating, flame heating, and/or one or more combinations thereof.
[0104] In one embodiment, after locally heating the proximal and distal sections 204, 206 of the suture needle 200, the suture needle is preferably quenched to room temperature.
[0105] In one embodiment, after quenching the suture needle to room temperature, the suture needle may be tempered for increasing the ductility of the suture needle.
[0106] Referring to
[0107] In one embodiment, the wire strand 280 is preferably heated to a first temperature of between about 450-700 degrees Celsius for hardening the wire strand 280. In one embodiment, the hardened wire strand 280 may be separated (e.g., cut) into a plurality of individual needle blanks.
[0108] Referring to
[0109] In one embodiment, the mid-section 310 of the elongated body 302 is preferably locally heated to a second temperature that is greater than 700 degrees Celsius, while maintaining the proximal and distal sections 304, 306 of the elongated body 302 of the suture needle 300 at a temperature that is below 700 degrees Celsius so that the mid-section 310 of the elongated body 302 is transformed into a bendable region 310 of the suture needle 300 that is softer and more flexible than the stronger, stiffer, and harder proximal and distal sections 304, 306 of the suture needle 300.
[0110] In one embodiment, the bendable region 310 may be locally heated using various methodologies including but not limited to electrical resistance heating, laser heating, induction heating, flame heating, hot gas heating, and/or combinations thereof.
[0111] In one embodiment, the wire strand 280 (
[0112] The softened, bendable region 310 may be located in the middle of the suture needle 300, or may be offset from the middle of the suture needle (e.g., somewhat closer to the distal point 308 or the proximal end of the suture needle). Using a heat treatment to soften the metal or alloy and provide increased reshape ductility to the bendable region 310 may be applied in conjunction with the mechanical processes described herein (e.g., providing flat surfaces to form a thinner or reduced outer diameter wire section shown in
[0113] In one embodiment, the suture needle 300 shown and described above in
[0114] In one embodiment, the bendable region 310 is preferably more flexible and less rigid than the proximal and distal sections 304, 306 of the elongated body 302 of the suture needle 300. As such, the proximal and distal sections 304, 306 of the suture needle 300 preferably maintain their respective original arc shapes as the suture needle 300 is transformed between the unbent configuration (
[0115] In one embodiment, the suture needle 300 shown in
[0116] If the needle is made from an alloy that cannot exhibit substantial strengthening via a martensitic transformation, such as an austenitic stainless steel and most martensitic-aged stainless steels that exhibit relatively low amounts of carbon or nitrogen or that contain trace amounts of carbon or nitrogen, different methods should be used to produce a needle with a bendable region. Examples of such alloys used by Ethicon include ETHALLOY, 455, 4310 (similar to 302), and W-26% Re. ETHALLOY and 455 are martensitic-aged alloys and may be precipitation strengthened.
[0117] Referring to
[0118] In one embodiment, the hardened wire strand 380 may be separated (e.g., cut) into a plurality of individual needle blanks. Referring to
[0119] In one embodiment, the mid-section 410 may be transformed into a bendable region of the suture needle by heat treating the martensitic-aged alloy. In one embodiment, the mid-section 410 is preferably locally heated to a first temperature that is greater than 700 degrees Celsius while maintaining the proximal and distal sections of the suture needle at a temperature that is below 700 degrees Celsius so that the mid-section 410 of the elongated body 402 transforms into a bendable region of the suture needle 400 that is softer and more flexible than the proximal and distal sections of the suture needle.
[0120] In one embodiment, after locally heating the bendable region 410 to greater than 700 degrees Celsius, the suture needle may be cooled to room temperature.
[0121] In one embodiment, after cooling the suture needle 400 to room temperature, the proximal and distal sections 404, 406 of the suture needle 400 may be heated to a second temperature of about 450-700 degrees Celsius while maintaining the bendable region 410 of the suture needle 400 at a temperature that is below the second temperature.
[0122] In one embodiment, the martensitic-aged alloy may be 455SS or a stainless steel sold under the trademark ETHALLOY having a composition of about 73% iron, 12% chrome, 10% nickel 10%, 3% molybdenum 3%, and 2% titanium.
[0123] In one embodiment, the bendable region of the suture needle may be locally heated using various heating methodologies including but not limited to electrical resistance heating, laser heating, induction heating, flame heating, hot gas heating, and/or combinations thereof.
[0124] In one embodiment, the bendable region of the suture needle may be covered and/or clamped with a heat sink while heating the proximal and distal sections of the suture needle to the second temperature of about 450-700 degrees Celsius for maintaining the bendable region of the suture needle below the second temperature.
[0125] In one embodiment, the suture needle 400 shown and described above in
[0126] In one embodiment, the bendable region 410 is preferably more flexible and less rigid than the proximal and distal sections 404, 406 of the elongated body 402 of the suture needle 400. As such, the proximal and distal sections 404, 406 of the suture needle 400 preferably maintain their respective original arc shapes as the suture needle 400 is transformed between the unfolded configuration (
[0127] In one embodiment, the suture needle 400 shown in
[0128] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, which is only limited by the scope of the claims that follow. For example, the present invention contemplates that any of the features shown in any of the embodiments described herein, or incorporated by reference herein, may be incorporated with any of the features shown in any of the other embodiments described herein, or incorporated by reference herein, and still fall within the scope of the present invention.