Oval dilator and retractor set and method

• US 20040059339A1
• Filed: 09/19/2002
• Published: 03/25/2004
• Est. Priority Date: 09/19/2002
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Inventors: Null, William B., Roehm, Thomas E. III
• Granted Patent: US 7,074,226 B2
• Time in Patent Office: Days
• US Class Current: 606/90
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 17/3421 Cannulas
• CPC Class Codes: A61B 2017/3445 used as instrument channel for multiple instruments catheters A61B2017/22072
• CPC Class Codes: A61B 2017/3447 Linked multiple cannulas

Abstract

Access to a greater area of surgical site with minimally invasive procedure is obtained by using two sets of sequentially placed tissue dilators oriented with their axes in a plane parallel to the spinal axis and a final non-circular dilator encompassing the two sets, followed by a non-circular tubular retractor providing a working channel extending longitudinally of the spine.

Claims

1. A dilator for use in soft tissue of a human body to provide an access channel to a planned surgery site adjacent the spine and comprising:

a tube having a proximal end and a distal end and a longitudinal axis;

said tube having a non-circular cross-sectional shape in a plane perpendicular to said longitudinal axis at a first location proximate said distal end.

2. The dilator of claim 1 and wherein:

said tube has non-circular cross-sectional shape in planes perpendicular to said longitudinal axis, said shape extending from said first location proximate said distal end to a second location at least eighty percent of the distance from said distal end to said proximal end.

3. The dilator of claim 2 and wherein:

said tube has a non-circular cross-sectional shape throughout its length from said distal end to said proximal end.

4. The dilator of claim 2 and wherein:

the shape of said non-circular cross-sectional shape of said tube is the same from said first location to said second location and has a major axis and a minor axis.

5. The dilator of claim 4 and wherein:

the overall dimension of said dilator along the major axis is between 28 and 40 mm; and

the overall dimension of said dilator along the minor axis is between 14 and 20 mm.

6. The dilator of claim 4 and wherein:

said shape is elongate with parallel sides and circular ends with radii, the centers of the end radii being on a line bisecting the minor axis.

7. The dilator of claim 6 and wherein:

said tube has perimetrical external ribs longitudinally-spaced in a series extending from said proximal end toward said distal end.

8. The dilator of claim 1 and wherein said tube has a channel therethrough, said channel being adapted to receive a pair of side-by-side dilators each having a circular cross-section transverse to a longitudinal axis thereof.

9. The dilator of claim 1 and wherein said tube has an exterior surface defining said non-circular cross-sectional shape, said exterior surface adapted to receive a retractor having a working channel with a cross-sectional shape corresponding to said cross-sectional shape of said exterior surface.

10. A dilator combination used in soft tissue of an animal body to provide access to a planned surgical site adjacent the spine and comprising:

a first set of telescoped tissue-dilator tubes coaxial with a first axis;

a second set of telescoped tissue-dilator tubes coaxial with a second axis; and

an enveloping dilator tube having a proximal end and a distal end and a non-circular cross-section, said enveloping dilator tube encompassing said first and second sets of dilator tubes and slidably received on said first and second sets.

11. The combination of claim 10 and wherein:

for said enveloping dilator tube, said non-circular cross-section extends from a first location proximate said distal end to a second location at least eighty percent of the distance from said distal end to said proximal end.

12. The combination of claim 11 and wherein:

said non-circular cross-section has a shape in a plane perpendicular to said first axis;

said shape is the same from said first location to said second location; and

said shape has a major axis and a minor axis.

13. The combination of claim 12 and wherein:

the overall dimension of said enveloping dilator along said major axis is between 28 and 40 mm; and

the overall dimension of said enveloping dilator along said minor axis is between 14 and 20 mm.

14. The combination of claim 12 and wherein:

said shape is elongate with parallel sides and circular ends with radii, the radii centers of the ends being on a line bisecting the minor axis.

15. The combination of claim 10 and wherein:

said enveloping dilator tube has perimetrical external ribs longitudinally spaced in a series extending from said proximal end toward said distal end.

16. A method for dilating soft tissue for accessing a planned surgery site on the spine of a patient, the spine having a primary axis extending in a cranial to caudal direction at the surgery site, the method comprising:

making an incision in the skin of the patient;

inserting the distal end of a first dilator tube through the incision and advancing the distal end thereof toward a vertebra at the surgery site;

inserting the distal end of a second dilator tube through the incision and advancing the distal end thereof toward a vertebra at the surgery site, and placing said distal ends of said dilator tubes on a line generally parallel to the primary axis of the spine at the surgery site;

advancing the distal end of a third dilator tube along said first dilator tube toward the surgery site;

advancing the distal end of a fourth dilator tube along said second dilator tube toward the surgery site;

encompassing portions of said third and fourth dilator tubes with a final dilator tube having a non-circular tubular cross-section, and advancing said final dilator tube along said third and fourth dilator tubes simultaneously and toward the surgery site; and

advancing a tubular retractor having a non-circular cross section along said final dilator to the surgery site.

17. The method of claim 16 and further comprising:

removing said dilator tubes to provide a working channel through said tubular retractor.

18. The method of claim 16 and wherein said tubular retractor is oval in cross-sectional shape, with the oval having a major axis and a minor axis, the method further comprising:

orienting said tubular retractor such that said major axis of the oval is generally parallel to the primary axis of the spine at the surgery site.

19. The method of claim 16 and further comprising:

prior to encompassing portions of said third and fourth dilator tubes with said final dilator tube advancing the distal end of a fifth dilator tube along said third dilator tube toward the surgery site;

advancing the distal end of a sixth dilator tube along said fourth dilator tube toward the surgery site, and then

advancing said final dilator tube along said fifth and sixth dilator tubes simultaneously toward the surgery site; and

then

advancing said tubular retractor along said final dilator to the surgery site.

20. The method of claim 19 and further comprising:

removing said dilator tubes to provide a working channel through said tubular retractor.

21. A method for placing a working channel tissue retractor at a planned surgery site on the spine of a patient, the spine having a primary axis extending in a cranial to caudal direction at the surgery site, the method comprising:

making an incision in the skin;

inserting a distal end of a first tissue dilator tube through the incision and advancing said distal end of said first dilator tube to a location at the surgery site;

inserting a distal end of a second tissue dilator tube through the incision and advancing said distal end of said second dilator tube to a location at the surgery site;

inserting a distal end of a third tissue dilator tube concentric with said first tube through the incision and advancing said third dilator tube along said first tube to a location at the surgery site;

inserting a distal end of a fourth tissue dilator tube concentric with said second tube through the incision and advancing said fourth tube along said second tube to a location at the surgery site;

inserting a distal end of a fifth tissue dilator tube concentric with said first tube through the incision and advancing said fifth tube along said third tube to a location at the surgery site;

inserting the distal end of a sixth tissue dilator tube concentric with said second tube through the incision and advancing said sixth tube along said fourth tube to a location at the surgery site;

inserting through the incision the distal end of a non-circular shaped tissue dilator tube and encompassing portions of said fifth and sixth tubes with said non-circular shaped tube and advancing said non-circular shaped tube along said fifth and sixth tubes simultaneously to a location at the surgery site; and

,

inserting a distal end of a tubular working channel tissue retractor through said incision and encompassing said non-circular shaped dilator tube with said retractor and advancing said retractor along said non-circular shaped tube to a location at said surgery site.

22. The method of claim 21 and further comprising:

removing said dilators to provide a working channel through said retractor.

23. The method of claim 21 and wherein said first, second, third, fourth, fifth and sixth dilator tubes have circular cross sections and longitudinal axes, the method further comprising:

orienting said first, third and fifth dilator tubes with their axes parallel to the axes of said second, fourth and sixth dilator tubes; and

orienting the axes to lie in a plane parallel to said primary axis of the spine at the surgical site.

24. The method of claim 21 and wherein, with the tubular retractor having a non-circular cross-sectional shape, and with the shape having a major axis and a minor axis, the method further comprises:

orienting the tubular retractor as it is advanced along the non-circular dilator tube such that the major axis of the shape is generally parallel to the said primary axis of the spine at the surgery site.

25. The method of claim 21 and further comprising, prior to advancing said non-circular shaped dilator tube:

inserting the distal end of a seventh tissue dilator tube concentric with said first tube through the incision and advancing said seventh tube along said fifth tube to a location at the surgery site;

inserting the distal end of an eighth tissue dilator tube concentric with said second tube through the incision and advancing said eighth tube along said sixth tube to a location at the surgery site;

advancing said non-circular shaped tissue dilator tube along said seventh and eighth tissue dilators tubes simultaneously to a location at the surgery site; and

advancing a tubular retractor along said non-circular shaped tissue dilator tube to a location at the surgery site.

26. The method of claim 25 and further comprising:

removing said dilator tubes to provide a working channel through said tubular retractor.

27. The method of claim 25 and wherein said first, second, third, fourth, fifth, sixth, seventh and eighth dilator tubes have circular cross sections and longitudinal axes, the method further comprising:

orienting a first dilator set comprising said first, third, fifth and seventh dilator tubes with their axes parallel to the axes of a second dilator set comprising said second, fourth, sixth and eighth dilator tubes; and

orienting the sets so that their axes lie in a plane parallel to a plane containing said primary axis of the spine at the surgical site.

28. A method for dilating soft tissue for accessing a planned surgery site on the spine of a patient, the spine having a primary axis extending in a cranial to caudal direction at the surgery site, the method comprising:

making an incision in the skin of the patient;

inserting a distal end of a first guide wire through said incision and advancing said distal end of said first guide wire into contact with a tissue structure at the surgery site;

advancing a first dilator tube onto a proximal end of said first guide wire and along said guide wire toward the surgery site;

inserting through said incision a distal end of a second guide wire and advancing said second guide wire to place said distal end of said second guide wire into contact with the tissue structure at the surgery site;

orienting said guide wires such that a line from said distal end of said second guide wire to said distal end of said first guide wire is generally parallel to said primary axis of the spine at the surgery site;

advancing a second dilator tube onto a proximal end of said second guide wire and along said second guide wire toward the surgery site;

advancing a third dilator tube along said first dilator tube toward the surgery site;

advancing a fourth dilator tube along said second dilator tube toward the surgery site;

encompassing portions of said third and fourth dilator tubes with a final dilator tube having a non-circular tubular cross section and advancing said final dilator tube along said third and fourth dilator tubes simultaneously and toward the surgery site; and

advancing a tubular retractor having a non-circular cross-section along said final dilator tube to the surgery site.

29. The method of claim 28 and further comprising:

removing said guide wires and dilator tubes to provide a working channel through said tubular retractor.

30. The method of claim 28 and wherein said tubular retractor is oval in cross-sectional shape, with the oval having a major axis and a minor axis, the method further comprising:

orienting said tubular retractor such that said major axis of said oval is generally parallel to said primary axis of said spine at the surgery site.

31. The method of claim 28 and further comprising:

prior to encompassing portions of said third and fourth dilator tubes,

advancing a fifth dilator tube along said third dilator tube toward the surgery site;

advancing a sixth dilator tube along said fourth dilator tube toward the surgery site, and then

encompassing portions of said fifth and sixth dilator tubes with said final dilator tube and advancing said final dilator tube along said fifth and sixth dilator tubes simultaneously toward the surgery site; and

advancing said non-circular tubular retractor along said final dilator tube to the surgery site.

32. The method of claim 31 and further comprising:

removing the said guide wires and dilator tubes to provide a working channel through said tubular retractor.

33. A method for placing a working channel tissue retractor at a planned surgery site on the spine of a patient, the spine having a primary axis extending in a cranial to caudal direction at the surgery site, the method comprising:

making an incision in the skin;

providing a tubular retractor having a working channel that is oval in cross-sectional shape, with the oval shape having a major axis and a minor axis;

orienting said tubular retractor such that the major axis of the oval shape is generally parallel to the said primary axis of the spine at the surgery site; and

advancing said oriented tubular retractor to the surgery site.

34. The method of claim 33, wherein prior to advancing said tubular retractor said method comprises:

inserting a distal end of a first guide wire through the incision and advancing said distal end of said first guide wire into contact with a vertebra at the surgery site;

advancing a first dilator tube onto a proximal end of said first guide wire and along said first guide wire toward the surgery site;

inserting through the said incision a distal end of a second guide wire and advancing said second guide wire to place said distal end of said second guide wire into contact with a vertebra at the surgery site;

orienting said guide wires such that a line from said distal end of said second guide wire to said distal end of said first guide wire is generally parallel to said primary axis of the spine at the surgery site; and

advancing a second dilator tube onto a proximal end of said second guide wire and along said second guide wire toward the surgery site.

35. The method of claim 34 and further comprising:

removing said guide wires and dilator tubes from said working channel through said tubular retractor after advancing said tubular retractor.

36. The method of claim 34, wherein prior to advancing said tubular retractor said method comprises:

encompassing portions of said first and second dilator tubes with a final dilator tube having a non-circular tubular cross section and advancing said final dilator tube along said first and second dilator tubes simultaneously and toward the surgery site, said final dilator having an exterior cross-section adapted for receipt in said working channel of said tubular retractor.

37. The method of claim 33, wherein said working channel extends extradiscally along at least a portion of at least two vertebrae when said tubular retractor is advanced to the surgery site.