Disposable arthroscopic suture cutting device

Abstract

A suture cutter that can easily load and hold a tensioned or untensioned suture in place for cutting. The cutter has a handle with an integral stem, and a shaft coupled to and extending from the handle. A tip has a cutting channel with a cradle for catching a suture before cutting. A piston in the handle drives a blade pusher to cut the suture in response to movement of the stem. A guide assembly in the body is formed by a pair of members that fold together via a living hinge to provide a slot for the head of the piston. The pusher is planar and horizontally oriented within the shaft, while the blade is planar and vertically oriented at a right angle to the pusher. The blade has a tab that is captured by a notch in the pusher to interlock the blade and the pusher.

Description

TECHNICAL FIELD

[0001] The present invention relates to a disposable surgical suture cutting device, and more particularly, to a cutting device with improved suture sealing. BACKGROUND

[0002] Surgical sutures are used as part of nearly every surgical procedure. Even though the medical industry generally uses the generic term "suture" to describe the filaments used in these surgical procedures, suture materials can vary depending on the task to be accomplished. Suture materials can be used that rival stainless steel wire in strength while maintaining the flexibility of lower strength materials. For example, ultra-high molecular weight polyethylene is now used as non-absorbable suture at locations such as knee, shoulder, and other connective tissue repairs where the surrounding tissue and / or suture anchors can support the additional load that such high strength suture materials can generate. As a result, as the strength of suture materials increases, they can be difficult to cut. The conventional method of addressing high strength suture materials involves the use of suture cutters designed to cut a variety of suture materials. However, these devices are not always adept at capturing and holding the suture to be cut, especially in situations where the tension on the suture changes after the suture is not tensioned or captured. Therefore, there is a need in the art for a suture cutter with improved suture loading and capture. SUMMARY

[0003] The present invention is a suture cutter that can easily load and hold a tensioned or untensioned suture in place for cutting. The suture cutter has a handle having a body and a lever integrally formed with the body such that the lever is biased back to an initial position if the lever is moved by a user from the initial position to an actuated position. A shaft is coupled to and extends longitudinally from the handle. A tip has a channel extending laterally across the tip that permits access to a cradle and a blade movable within the tip between a retracted position and an extended position, where the blade traverses the cradle. A piston is positioned within the handle and longitudinally movable within the handle in response to movement of the lever. A propeller is interconnected to the blade and the piston such that movement of the lever from the initial position to the actuated position moves the blade from the retracted position to the extended position. The body includes a guide assembly having a pair of opposing members having a pair of corresponding opposing slots aligned to form a guide for a head of the piston. The pair of opposing members of the guide assembly are coupled together by a pair of living hinges. The piston includes a post extending from the head of the piston to engage the lever. A pivot block is positioned in the body contiguous to the piston such that movement of the lever against the post of the piston moves the head of the piston longitudinally within the guide of the guide assembly. The propeller is planar and horizontally oriented within the shaft. The blade is planar and vertically oriented within the shaft at a right angle to the propeller. The blade has a tab captured by a notch in the propeller to interlock the blade and the propeller. The shaft includes a plurality of slots captured by a corresponding plurality of detents of the guide assembly.

[0004] In one embodiment, the channel of the tip tapers inwardly from a first wider diameter to a second narrower diameter proximate the cradle. In another embodiment, the channel of the tip can be undulating to deter the suture from exiting the channel. In another embodiment, the tip includes a cover longitudinally slidable between a first position closing communication with the channel and a second position opening communication with the channel. BRIEF DESCRIPTION OF DRAWINGS

[0005] The present invention will be more fully understood and appreciated by reading the following of the invention in conjunction with the accompanying drawings, in which:

[0006] Figure 1 is a perspective view of a suture cutter according to the present invention in a fully assembled state;

[0007] Figure 2 is a view of a suture cutter according to the present invention in a partially assembled state with the piston guide unfolded;

[0008] Figure 3 is a view of a suture cutter handle according to the present invention in a partially assembled state with the piston guide unfolded, the piston displaced, and the lever in an unbiased position;

[0009] Figure 4This is a view of the stitching in both partially and fully assembled states, showing the piston guide folded into place to complete the assembly of the body, piston, and rod;

[0010] Figure 5 This is a perspective view of the shaft for a suture thread cutter according to the present invention;

[0011] Figure 6 This is a side view of the shaft for a suture cutter according to the present invention;

[0012] Figure 7 These are side and close-up views of the cutting tip of a suture cutter according to the present invention;

[0013] Figure 8 It is a side view of the blade used for a suture cutter, and a bottom view of the tip, which shows the interlocking structure of the blade and the tip;

[0014] Figure 9 This is a side view of a blade pusher for a suture cutter according to the present invention;

[0015] Figure 10 This is a cross-section showing the orientation of the pusher and blade according to the invention in a suture cutter;

[0016] Figure 11 These are a pair of opposing side views of the tip of the suture capture channel surface according to the invention; and

[0017] Figure 12 This is a side view of another embodiment of the cutting tip for a suture cutter according to the present invention. Detailed Implementation

[0018] Referring to the diagram, the same number always refers to the same part. Figure 1 The suture cutter 10 can be seen, which has a handle 12, a hollow shaft 14 extending from the handle 12, and a tip 16 positioned at the end of the hollow shaft 14. (Reference) Figure 2 The blade 18 is housed in the tip 16 and operated by a pusher 20, which extends within a hollow shaft 14 between the blade 18 and the handle 12. The pusher 20 is preferably formed from a flat material and is horizontally oriented within the shaft 14.

[0019] refer to Figure 3 The handle 12 includes a flexible rod 24 integrally formed with the body 26 of the handle 12 to provide a flexible mechanism that can store energy when squeezed by the user, so that the rod 24 will return to its original position when released by the user. Figure 3The handle is depicted in a pre-assembled configuration. As described herein, when fully assembled, rod 24 is positioned to engage piston 30, which can drive flat material feed pusher 20 to actuate blade 18 in tip 16, thereby cutting the suture trapped within tip 16. Piston 30 includes a head 32 and a strut 34 extending from the head 32. Head 32 includes a horizontally extending slot 36 that can engage pusher 20. Piston 30 is coupled within body 26 by guide assembly 40, which includes a pair of opposing members 42 and 44 coupled together via a pair of movable hinges 46 and 48 that allow easy assembly of cutter 10. Opposing members 42 and 44 include a pair of slots 52 and 54, which, when fully assembled, Figure 4 As seen, when the opposing members 42 and 44 are folded around the movable hinges 46 and 48, the slot will capture the piston head 32 and constrain its movement along the longitudinal axis of shaft 14, and drive the actuator 20 in response to the movement of rod 24. Corresponding snap-fit ​​features 56 and 58 allow the opposing members 42 and 44 to fold as shown in the image. Figure 4 As seen, when folded around the movable hinges 46 and 48, it is fixed in the appropriate position around the piston head 32. Figure 4 The relative members 42 and 44 are shown in the folded and then folded positions.

[0020] refer to Figure 4 After the opposing components 42 and 44 are folded around the movable hinges 46 and 48, the strut 34 of the piston 30 extends from the guide assembly 40 to engage the rod 24. Figure 3 As seen, the pivot block 60 extends across the handle 12, such that actuation of the strut 34 via the rod 24 causes the piston head 32 to travel longitudinally along slots 52 and 54. When the piston head 32 is engaged with the pusher 20 via slot 36, movement of the rod 24 longitudinally along the axis 14 drives the pusher 20 to actuate the blade 18 within the tip 16. Opposite members 42 and 44 also form a stop 62 within the handle 12, which restricts movement of the strut 34 of the piston 30 and thus limits the rod 24, preventing the user from over-acting on the cutter 10.

[0021] refer to Figure 5 and 6 The shaft 14 is captured within the handle 12 and secured by a plurality of pawls 70 in the guide assembly 40 of the handle 12 to prevent movement. The pawls interact with a pair of opposing recesses 72 and 74 and a third end recess 76 in the shaft 14, which can engage the shaft 14 to the handle 12 and prevent the shaft 14 from rotating relative to the handle 12.

[0022] refer to Figure 7A shaft 14 supports a tip 16, which is wavy to define a tapered channel 90 that extends laterally across the shaft 14 and narrows into a support 92. The channel 90 tapers from a first wider diameter (d1) that allows capture of a portion of a taut suture to a second narrower diameter (d2) at the support 92. The second narrower diameter (d2) of the groove 303 is dimensioned to be smaller than the diameter of an untaut suture. The channel 90 of the tip 16 is oriented such that the tip 16 can be guided by a user under the suture and then lifted to allow the suture to converge through the tapered channel 90 and into the support 92. Reference Figure 8 The lower side of the tip 16 includes a groove 96 that extends longitudinally and captures the tabs 98 of the blade 18 to control the longitudinal movement of the blade 18. The sharp edge 100 of the blade 18 is positioned to move across the support 92 when driven by the pusher 20, and thus cut any sutures captured in the support.

[0023] refer to Figure 9 The pusher 20 includes a notch 102 for engaging the tab 104 on the blade 18. For example... Figure 10 As seen, the pusher 20 is horizontally oriented within the shaft 14 to engage the piston 30, while the blade 18 is vertically oriented within the tip 16. This vertical relationship between the pusher 20 and the blade 18 allows the pusher 20 and the blade 18 to be engaged within the shaft 14 using only the mechanical constraints of the shaft 14 without the use of additional fasteners or adhesives.

[0024] refer to Figure 11 The tip 16 may include opposing blocking surfaces 110 and 112 extending into the channel 90 on opposite sides and having an upper portion that imparts a slight twist to the suture while allowing it to slide into the channel, where it is released from the blocking surfaces 110 and 112. Once the suture has been fully moved into the channel 90, the lower portions of the blocking surfaces 110 and 112 prevent the tensioned suture from unintentionally slipping out of the channel 90.

[0025] refer to Figure 12In another embodiment, tip 16 may include a channel cover 114 biased to cover channel 90, but longitudinally slidable to allow and then block communication into and out of channel 90 in response to contact with suture. For example, when the suture engages with cover 114, support surface 116 may provide a force that causes cover 114 to slide longitudinally toward handle 12 to allow the suture into channel 90. Once the suture has fallen into channel 90 and then into holder 92, cover 114 may return to its original position to retain the suture in channel 90 until it is cut by blade 18. This embodiment does not require tension on the suture to keep it captured in holder 92 of tip 16 and to prevent uncoordinated suture from unintentionally leaving holder 92, because no tension is required on the suture to keep it trapped within holder 92.

Claims

1. A suture cutter, comprising: A handle having a body and a rod integrally formed therewith, such that if the rod is moved by a user from an initial position to an actuated position, the rod is biased back to the initial position; A shaft, which is connected to the handle and extends longitudinally from the handle; The tip has a channel extending laterally across the tip that allows access to the support and a blade that can move within the tip between a retracted position and an extended position, wherein the blade extends laterally through the support. A piston, which is positioned within the handle and is capable of moving longitudinally within the handle in response to movement of the rod; as well as A thruster, interconnected to the blade and the piston, causes the blade to move from the retracted position to the extended position by movement of the rod from the initial position to the actuated position.

2. The suture cutter of claim 1, wherein the body comprises a guide assembly having a pair of opposing members having a pair of corresponding opposing grooves aligned to form a guide for the head of the piston.

3. The suture cutter of claim 2, wherein the pair of opposing members of the guide assembly are connected together by a pair of movable hinges.

4. The suture cutter of claim 3, wherein the piston includes a support extending from the head of the piston to engage the rod.

5. The suture cutter of claim 4, further comprising a pivot block positioned in the body adjacent to the piston such that movement of the rod against the strut of the piston causes the head of the piston to move longitudinally within the guide of the guide assembly.

6. The suture cutter of claim 5, wherein the pusher is planar and horizontally oriented within the axis.

7. The suture cutter of claim 6, wherein the blade is planar and vertically oriented within the axis at a right angle to the pusher.

8. The suture cutter of claim 7, wherein the blade has a tab that is captured by a notch in the pusher to interlock the blade and the pusher.

9. The suture cutter of claim 8, wherein the shaft comprises a plurality of slots captured by corresponding plurality of pawls of the guide assembly.

10. The suture cutter of claim 9, wherein the channel at the tip tapers inward from a first wider diameter to a second narrower diameter near the support.

11. The suture cutter of claim 9, wherein the channel at the tip is wavy to prevent the suture from leaving the channel.

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