Flexible articulate surgical tool

Patent metadata

Field	Value
Publication number	US-11730505-B2
Application number	US-201716468042-A
Country	US
Kind code	B2
Filing date	Dec 18, 2017
Priority date	Dec 16, 2016
Publication date	Aug 22, 2023
Grant date	Aug 22, 2023

Abstract

A flexible elongate shaft assembly which includes an elongate flexible tube having at least one joint built into the elongate flexible tube, and the at least one joint comprised of at least one notch. Each notch includes a contact-aided compliant notch topology built into the elongate flexible shaft configured to cause each notch to mechanically interfere with itself and self-reinforce during bending of each notch resulting in an increase in stiffness of each notch to prevent buckling and plastic deformation of the elongate flexible shaft assembly, and assume a predetermined and designed bending shape of the elongate flexible shaft assembly. The flexible elongate shaft assembly is incorporated into a flexible articulate surgical tool that provides the needed stiffness in order to be able to manipulate tissue and bear loads in anatomically confined spaces. The surgical tool includes a clinician operated handle, the flexible elongated shaft assembly extending from the handle to a surgical tool with the flexible elongate tube having one or more joint sections located near the surgical tool. A flexible cable connects the handle to the surgical tool. The joint sections are configured so that when the clinician activates the surgical tool, a mechanical interference is generated in each of the notches and this mechanical interference not only increases stiffness throughout the articulation of the notch's range-of-motion but it also serves the dual purpose of controlling the bent “shape” of the flexible portion of the notch.

First claim

Therefore what is claimed is:

1. A flexible elongate shaft assembly, comprising:
an elongate flexible shaft having at least one joint built into the elongate flexible shaft, the at least one joint comprised of at least one notch, with each notch having an internal section contact-aided compliant notch topology within each notch configured to cause the internal section of each notch, upon bending in which each notch is bending when each notch's internal section contact-aided compliant notch topology is deforming and the strain on the material of the contact-aided compliant notch topology is changing, to
mechanically interfere with itself and self-reinforce prior to each notch being fully bent resulting in an increase in stiffness of each notch prior to being fully bent and to prevent buckling and plastic deformation of the elongate flexible shaft, and
assume a predetermined and designed bending shape of the at least one joint and hence the elongate flexible shaft.

2. The flexible elongate shaft assembly according to claim 1 , wherein the elongate flexible shaft is an elongated tube having a longitudinal axis, and wherein the contact-aided compliant notch topology comprises
a generally transverse notch segment extending from a first side of the elongated tube towards an opposed second side of the elongated tube and terminating at a predetermined termination position adjacent to, and spaced from, the second side of the elongated tube, the generally transverse notch segment dividing the elongated tube into a proximal tube section located on one side of the generally transverse notch segment and a distal tube section located on the other side of the generally transverse notch segment,
an elongated notch segment extending from the generally transverse notch segment at the predetermined termination position in a direction generally parallel to the longitudinal axis to define a flexible outer strip tube section along the opposed second side of the elongated tube connecting the proximal and distal tube sections, and
wherein the elongated notch segment has a preselected width such that upon movement of the distal tube section, relative to the proximal tube section, in a direction from the second side towards the first side, an inner surface of the flexible outer strip tube section adjacent to the elongated notch segment comes into physical contact with an internal section of the proximal tube section adjacent to both the predetermined termination position and the elongated notch segment causing the at least one notch to mechanically interfere with itself and self-reinforce throughout the range-of-motion of the at least one notch.

3. The flexible elongate shaft assembly according to claim 2 , wherein the preselected width of the elongated notch segment is selected to give a predetermined amount of movement of the distal tube section with respect to the proximal tube section prior to the inner surface of the flexible outer strip tube section adjacent to the elongated notch segment coming into physical contact with the internal section of the proximal tube section.

4. The flexible elongate shaft assembly according to claim 3 , wherein the preselected width of the elongated notch segment is variable such that at a transition zone between the generally transverse notch segment and the elongated notch segment, the width of the elongated notch segment, defined as the distance between the inner surface of the flexible outer strip tube section adjacent to the elongated notch segment and the internal section of the proximal tube section, varies between an initial width to a final width, where the initial width is greater than the final width.

5. The flexible elongate shaft assembly according to claim 2 , wherein the generally transverse notch segment extending from the first side of the elongated tube towards the opposed second side of the elongated tube is tapered from a first opening size at the first side of the elongated tube down to a second opening size at the predetermined termination position such that the first opening size is greater than the second opening size, and wherein the first opening size is selected such that an end section of a distal tube section located on the first side of the elongated tube adjacent to the tapered notch segment and an end section of a proximal tube section located on the first side of the elongated tube adjacent to the tapered notch segment come into contact only at the end of a range-of-motion of each notch such that when the end section of the distal tube section located on the first side of the elongated tube adjacent to the tapered notch segment and the end section of the proximal tube section located on the first side of the elongated tube adjacent to the tapered notch segment come into contact each notch cannot bend anymore, and wherein the first opening size is selected to ensure contact occurs just before a flexible part of each notch reaches any plastic deformation.

6. The flexible elongate shaft assembly according to claim 2 , wherein the at least one joint is a plurality of joints spaced along the elongated tube.

7. The flexible elongate shaft assembly according to claim 6 , wherein the plurality of joints spaced along the elongated tube are aligned collinearly along the elongated tube such that the elongated tube actuates in a single plane upon application of a force.

8. The flexible elongate shaft assembly according to claim 6 , wherein the plurality of joints spaced along the elongated tube are aligned in a non collinear configuration around the elongated tube such that the elongated tube actuates in a plurality of planes upon application of a force.

9. The flexible elongate shaft assembly according to claim 6 , wherein the plurality of joints spaced along the elongated tube are aligned in a helical configuration around the elongated tube such that the elongated tube actuates in a plurality of planes upon application of a force.

10. The flexible elongate shaft assembly according to claim 9 , wherein the plurality of joints are spaced in a predetermined helical configuration around the elongated tube at a preselected angle spiral spacing with respect to each other.

11. The flexible elongate shaft assembly according to claim 10 , wherein the preselected angle spiral spacing is 120 degree spiral spacing.

12. The flexible elongate shaft assembly according to claim 10 , wherein the preselected angle spiral spacing is 90 degree spiral spacing.

13. The flexible elongate shaft assembly according to claim 2 , wherein including a cut-out located in the distal tube section located at an end of the generally transverse notch segment adjacent to the predetermined termination position configured to provide reduced strain concentration during bending of the flexible outer strip tube section.

14. The flexible elongate shaft assembly according to claim 2 , wherein the elongated notch segment includes an inner surface and an outer surface, and wherein the elongated notch segment is extended into the internal section of the proximal tube section in a spiral configuration such that multiple points of mechanical interference contact occur between the inner surface and outer surface of the elongated notch segment causing increased stiffness throughout the notch's range-of-motion; where the inner surface of the elongated notch segment is continuous with the inner surface of the flexible outer strip tube section and the outer surface of the elongated notch segment is continuous with the internal section of the proximal tube section adjacent to both the predetermined termination position and the elongated notch segment.

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Assignees

• Hospital For Sick Children

Inventors

• Eastwood Kyle W
• Francis Peter
• Looi Thomas
• Naguib Hani E
• Drake James M

Classifications

• A61B17/320016 Primary

  Endoscopic cutting instruments, e.g. arthroscopes, resectoscopes (A61B10/0233, A61B17/29, A61B17/3207 take precedence) · CPC title

• A61B17/295

  combined with cutting implements · CPC title

• A61B2017/0034

  adapted to be inserted through a working channel of an endoscope · CPC title

• A61B2017/00309

  Cut-outs or slits · CPC title

• A61B2017/00314

  Separate linked members · CPC title