ORGAN RESECTION STUMP FIXING CLIP
20220183690 · 2022-06-16
Assignee
- National University Corporation Kumamoto University (Kumamoto, JP)
- Kyushu University, National University Corporation (Fukuoka, JP)
Inventors
Cpc classification
A61B17/10
HUMAN NECESSITIES
A61B2017/00004
HUMAN NECESSITIES
International classification
A61B17/08
HUMAN NECESSITIES
A61B17/10
HUMAN NECESSITIES
Abstract
An object of the present invention is to provide a means for fixing a pancreatic resection stump created during an operation for resecting a portion of the pancreas. The present invention provides a polymeric surgical clip characterized in that the clip comprises a first arm portion, a second arm portion, and a resilient hinge portion joining the first and second arm portions together, both the arm portions are joined to the resilient hinge portion at their bases, the first arm portion has a convex outer surface and a concave inner surface clamping the pancreas, the second arm portion has a convex or flat outer surface and a concave or flat inner surface clamping the pancreas, the first arm portion forms at its distal end a deflectable hook portion curved toward the second arm portion, and the clip is configured so that, in a closed position, a distal end of the second arm portion enters inside the curved hook portion and engages with the hook portion to lock the clip in the closed position.
Claims
1. A polymeric surgical clip for a pancreatectomy comprising a first arm portion, a second arm portion, and a resilient hinge portion joining the first and second arm portions together, both the first and second arm portions being joined to the resilient hinge portion at their bases, the first arm portion having a convex outer surface and a concave inner surface clamping a pancreas, the second arm portion having a convex or flat outer surface and a concave or flat inner surface clamping the pancreas, the inner surface of the first arm portion and the inner surface of the second arm portion being in opposition to each other, the first arm portion forming at its distal end a deflectable hook portion curved toward the second arm portion, the polymeric surgical clip being thereby configured so that, in a closed position, a distal end of the second arm portion enters inside the curved hook portion and engages with the hook portion to lock the clip in the closed position, the polymeric surgical clip being characterized in that the first arm portion and the second arm portion keep substantially the same shape in an opened position and the closed position, and the inner surface of the first arm portion and the inner surface of the second arm portion clamping the pancreas are configured so that a space is created between both the inner surfaces.
2. The polymeric surgical clip according to claim 1, characterized in that the second arm portion has the convex outer surface and the concave inner surface clamping the pancreas, the inner surface of the first arm portion and the inner surface of the second arm portion are in opposition to each other to configure opposing curved surfaces.
3. The polymeric surgical clip according to claim 1, characterized in that a maximum distance created between the inner surface of the first arm portion and the inner surface of the second arm portion in the closed position is larger than any one of a thickness between the inner surface and the outer surface of the first arm portion or a thickness between the inner surface and outer surface of the second arm portion.
4. The polymeric surgical clip according to claim 1, wherein the thickness between the inner surface and the outer surface of the first arm portion is substantially the same as the thickness between the inner surface and the outer surface of the second arm portion.
5. The polymeric surgical clip according to claim 1, wherein the radius of curvature of the concave inner surface of the first arm portion is substantially equal to the radius of curvature of the concave inner surface of the second arm portion.
6. The polymeric surgical clip according to claim 1, wherein the first arm portion and the second arm portion each have one or two boss portions extending laterally.
7. The polymeric surgical clip according to claim 1, further having a bump portion on each of the inner surface near the base of the first arm portion and the inner surface near the base of the second arm portion.
8. The polymeric surgical clip according to claim 1, wherein the inner surface of the first arm portion and/or the inner surface of the second arm portion is an embossed surface or a surface provided with a plurality of protrusions.
9. The polymeric surgical clip according to claim 1, memorizing an overall shape of the clip in the closed position.
10. The polymeric surgical clip according to claim 1, comprising a bioabsorbable polymer.
11. The polymeric surgical clip according to claim 1, characterized by being used for fixation of a resection stump of the pancreas treated by a pancreatectomy.
12. The polymeric surgical clip according to claim 11, configured to clamp the pancreas at a pressure of at least 4 kPa or more when fixing the resection stump of the pancreas.
13. The polymeric surgical clip according to claim 1, characterized by being used for a surgical method selected from the group of a distal pancreatectomy, a pancreaticoduodenectomy, an enucleation of pancreatic tumor, and a middle pancreatectomy.
Description
BRIEF DESCRIPTION OF DRAWINGS
[0039]
[0040]
[0041]
[0042]
[0043]
[0044]
[0045]
[0046]
[0047]
[0048]
[0049]
[0050]
[0051]
Description of Embodiments
[0052] Hereinafter, the present invention will be illustrated with reference to the exemplary embodiments along with preferred methods and materials which can be used in practice of the present invention. Unless otherwise specified in the sentences, any technical terms and scientific terms used in the present specification have the same meaning as those generally understood by those of ordinary skill in the art to which the present invention belongs. Any materials and methods equivalent or similar to those described in the present specification can be used for practicing the present invention. All publications and patents cited herein in connection with the present invention described herein are incorporated by reference, for example, as indicating methodology, materials, etc. that can be used in the present invention.
[0053] In the present specification, when the expression “X to Y” is used, it means that X is included as a lower limit and Y as an upper limit, or that X is included as an upper limit and Y as a lower limit. In the present specification, “about” is used to mean that ±10% is allowed.
[0054] Though a surgical clip of the present invention is described below in detail, taking as an example a case where the clip is applied to a pancreas, the surgical clip of the present invention is usable for other similarly delicate and thick organs beside the pancreas, for example, a liver, a lung, an appendix, and an ovary. Therefore, the clip of the present invention is a clip for fixing a resection stump of a cut portion of an organ selected from a pancreas, a liver, a lung, an appendix, or an ovary, preferably a clip for fixing a resection stump of a pancreas.
[0055] The surgical clip of the present invention is provided with a first arm portion, a second arm portion, and a resilient hinge portion joining the first and second arm portions together, and both the first and second arm portions are joined together via the hinge portion at their bases. The first and second arm portions are configured to engage with each other at their terminating ends (distal ends) when the clip is in a closed position. The hinge portion is resilient, and allows the first arm portion and the second arm portion to move to an opened position, and to move from the opened position to the closed position. Each arm portion has an inner surface opposing an inner surface of the other arm portion. The inner surface of the first arm portion is concave. The inner surface of the second arm portion is concave or flat, preferably concave. This prevents their inner surfaces from closely overlap with each other even in the closed position where the terminating ends of the first arm portion and the second arm portion are engaged with each other, so that a space is secured between the inner surfaces of the first arm portion and the second arm portion. Therefore, even when a pancreas, which is a delicate organ, is clamped, excessive damage to the organ can be prevented.
[0056] The first arm portion has a hook portion at its terminating end, and the hook portion is deflectable (having a resiliently bending property) and curved toward the second arm portion. Since the hook portion is flexible, when the first and second arm portions move around the hinge portion from the opened position to the closed position, the distal end of the second arm portion abuts against the above hook portion, and when both the arm portions move further to the closed position, the hook portion deflects toward the outside of the first arm portion, so that the distal end of the second arm portion enters inside the hook portion of the first arm portion. This causes an outer surface of the distal end of the second arm portion to engage with the inside of the hook portion of the first arm portion, thereby locking the clip in the closed position.
[0057] The curved shape of the hook portion includes both gently-curving and sharply-curving shapes, and further includes a form that can be called a bend, but preferably it is a sharply curved state or a bent state. This forms a good state of engagement (state of locking) between the first arm portion and the second arm portion, and thus the clip can be kept in a good closed state. It should be noted that, if it is desired that an excessive load on the hook portion be avoided, or if it is desired that a space between the first and second arm portions be increased, or in other cases, a gentle curve can be used.
[0058] It is possible to curve the inner and outer surfaces of the hook portion continuously, and this prevents occurrence of excessive stress concentration in a corner portion.
[0059] The clip of the present invention can be provided with one or two cylindrical boss portions extending laterally, in a distal position from the hinge portion in, each of the first arm portion and the second arm portion, preferably two on both side surfaces. Since the boss portions are provided, when the clip is set on an applier, the clip can be stably held on the applier, and simultaneously an opening and closing operation of the clip can be facilitated by using the applier.
[0060] The surgical clip of the present invention can be used for fixation of a resection stump of a pancreas. Though not limited thereto, the clip of the present invention can be used in a pancreatectomy, for example, a distal pancreatectomy, a pancreaticoduodenectomy, a middle pancreatectomy, a tumor enucleation, preferably for a distal pancreatectomy. The surgical clip of the present invention can be used in order to fix pancreatic parenchyma, but preferably it is used in order to fix pancreatic parenchyma on a pancreatic head and body side after resection. It is preferred that a main pancreatic duct of a resection stump be ligated prior to fixing by the clip, but ligation does not have to be performed.
[0061] In addition, the surgical clip of the present invention can be used for fixation of a resection stump of a pancreas in a laparoscopic pancreatectomy by using it together with an applier.
[0062] Preferred embodiments of the surgical clip of the present invention are described below with reference to the drawings. It should be noted that the present invention is not limited to the embodiments described below.
[0063]
[0064] The first arm portion 1 has a concave inner surface 11 and a corresponding convex outer surface 12, and a hook portion 4 is disposed on its terminating end (distal end) side. The second arm portion 2 has a concave or flat inner surface 13 and a convex or flat outer surface 14, and terminates in a distal end 7 engaging with the hook portion 4.
[0065] The hook portion 4 is curved toward the second arm portion, and comprises a curved portion 5 and a distal end 6. The hook portion 4 is deflectable, and configured so that, when the first and second arm portions move around the hinge portion from the opened position to the closed position, the above hook portion 4 deflects toward the outside of the first leg member, and the distal end 7 of the second arm portion enters inside the above curved hook portion, and engages with the hook portion 4 to lock the clip in the closed position. In the closed state, the distal end 6 and the distal end 7 are put into an engaged state, thereby fixing the first arm portion and the second arm portion in the closed position.
[0066] In any state of the clip of the present invention, for example, in the opened state or the closed state, the first arm portion and the second arm portion are unchanged in shape, the same or substantially the same in shape. Therefore, in the closed state, the inner surface of the first arm portion is kept in a concave shape, whereas the inner surface of the second arm portion is kept in a concave or flat (preferably concave) shape, and thus a space can be secured between both the inner surfaces.
[0067] The inner shape of the hook portion 4 and the shape of the distal end 7 of the second arm portion are not particularly limited as long as they can engage with each other to fix a resection stump of a pancreas in the closed state. The shape of the curved portion 5 of the hook portion 4 includes both forms of a gentle curve and a sharp curve, and even a form that can be called a bend, but preferably it is a sharply-curved or bent state. It should be noted that, if it is desired that an excessive load on the hook portion be avoided, or if it is desired that a space between the first and second arm portions be increased, or in other cases, a gentle curve may be used. On the other hand, it is preferred that the shape of the distal end 7 of the second arm portion 2 be such a shape that the distal end 7 will easily enter inside the curved portion 5 in a curved or bent state and will not disengage while a pancreas is fixed, and, for example, it includes a shape decreasing in thickness toward its distal end. The hook portion 4 and the distal end 7 each may be provided with, for example, a claw in order to prevent them from disengaging after engagement. The hook portion 4 and the distal end 7 take these shapes, thereby facilitating fixation of a pancreatic head side of a cut portion of a pancreas, and simultaneously forming good engagement (state of locking) therebetween, so that the clip can keep a good closed state with the pancreas clamped therein.
[0068] In a preferred embodiment, a thickness between the inner surface 11 and the outer surface 12 in an almost entire portion of the first arm portion (namely most portions excluding the distal end and the base) is, as a whole, substantially constant throughout its length. In addition, in a preferred embodiment, a thickness between the inner surface 13 and the outer surface 14 in an almost entire portion of the second arm portion (namely most portions excluding the distal end and the base) is, as a whole, substantially constant throughout its length. In addition, it is preferred that the thickness of the first arm portion and the thickness of the second arm portion be substantially the same thickness. The thickness of the first arm portion or the second arm portion is not particularly limited, and can be selected appropriately according to the material used, but it is preferably 2 to 10 mm, more preferably 2 to 7 mm, even more preferably 2 to 6 mm.
[0069] The inner surface side 11 of the first arm portion is concave, and the radius of curvature of the concave inner surface can be selected appropriately according to the size and/or shape of an object to be fixed. The inner surface side 13 of the second arm portion is concave or flat, but preferably concave. When the inner surface side of the second arm portion is concave, the radius of curvature of the concave inner surface can be selected appropriately according to the size and/or shape of an object to be fixed. Since the inner surface 11 is concave, whereas the inner surface 13 is concave or flat, when the hook is closed, as shown in
[0070] The length of the clip of the present invention is not particularly limited, and can be selected appropriately according to the size and/or shape of an object to be fixed. Though not limited thereto, it is preferably 3 to 15 cm, more preferably 4 to 12 cm, even more preferably 5 to 10 cm.
[0071] The size of the hook portion 4 in the first arm portion of the clip of the present invention is not particularly limited, but the ratio of the hook portion 4 to the other portion (ratio of A:B) is preferably 1:2 to 1:10, more preferably 1:3 to 1:8, even more preferably 1:5to 1:7.
[0072] The clip of the present invention can be provided with an anti-slip mechanism on the inner surface of the first arm portion and/or the inner surface of the second arm portion in order to prevent the clip from slipping out of place and/or slipping off after the clip is fixed to a pancreas. The anti-slip mechanism is not particularly limited as long as it can prevent the clip from slipping out of place, and any mechanism may be used, and, for example, the anti-slip mechanism can be achieved by embossing the inner surface, or by providing the inner surface with a plurality of protrusions.
[0073] Another embodiment of the clip of the present invention is shown in
[0074] The clip of the present invention can also be manufactured using a shape-memory plastic material. The shape memorized in such a case is not particularly limited. It can be, for example, a clip memorizing a shape with the first arm portion and the second arm portion opened slightly, such as shown in
[0075] Such a clip having a shape memory property in a closed position as shown in
[0076] The clip of the present invention can also be used with an applier, which is particularly useful in the case of a laparoscopic operation. Though an example of using an applier is described with reference to
[0077]
[0078]
[0079] After the clip is set on the applier, the applier of the scissors shape is opened, and thereby the clip can be operated into a further opened state. The clip, in the further opened state, tries to return to its original shape, so that opposite forces act on the catching mechanism of the applier and the boss portion of the clip, and thus the clip can be prevented from dropping off from the applier when the clip opened approaches a pancreas. The clip opened is set on a pancreatic head side of a cut site of the pancreas, and thereafter the applier is closed, thereby locking the clip in the closed state.
[0080]
[0081]
[0082] Another embodiment is described below in which a clip is used that memorizes a shape with the first arm portion and the second arm portion closed, such as shown in
[0083] Another embodiment of the clip of the present invention is shown in
[0084] Another embodiment of the clip of the present invention is shown in
[0085] When a resection stump of a pancreas is fixed by the clip of the present invention, a main pancreatic duct, and further an accessary pancreatic duct, if necessary, of a pancreatic closure portion are closed, and thus leakage of pancreatic juice from the pancreatic stump (a pancreatic fistula) can be prevented. In order to prevent leakage of pancreatic juice, the main pancreatic duct needs to be closed by the clip so that the pressure-resistant performance of the main pancreatic duct is equal to or more than a certain level. It is desired that the pressure-resistant performance of the main pancreatic duct required in order to prevent leakage of pancreatic juice to prevent the pancreatic fistula be at least about 4 kPa or more, preferably about 5 kPa or more, more preferably about 6 kPa or more. Therefore, the pancreatic fistula can be prevented by fixing the resection stump of the pancreas by the clip of the present invention to such an extent that a desired pressure-resistant performance of the main pancreatic duct can be achieved. Therefore, it is desired that the clip of the present invention be configured to clamp a pancreas at a pressure of at least about 4 kPa or more, preferably about 5 kPa or more, even more preferably about 6 kPa or more, when fixing a resection stump of the pancreas, whereas it is desired that the clip be configured to clamp a pancreas at such a degree of pressure, as the upper limit, as not to cause necrosis of a closure portion of the pancreas clamped by the clip of the present invention.
[0086] It is desired that the clip of the present invention be manufactured as a plastic integrally-molded article. The plastic material is not particularly limited as long as it has biocompatibility, but preferably it is a commercially available biocompatible plastic or biodegradable plastic of a relatively high strength. Examples of preferred plastics are those used for a surgical implant operation. The plastic material can be selected freely from these plastic materials according to the purpose. Though not limited thereto, biocompatible materials, for example, can include polyethylene, Teflon (registered trademark), polyoxymethylene, polyurethane, polydioxanone, poly(ε-caprolactone), polyvinyl chloride, polypropylene, polymethylmethacrylate, polystyrene, and their derivatives, and biodegradable or bioabsorbable materials, for example, can include polyglycolic acid, polylactic acid, and their copolymers, polydioxanone, and poly(ε-caprolactone), as well as their derivatives. In addition, the plastic materials can include a blend of a plurality of any of the above materials in any ratio.
[0087] In a case where the clip of the present invention is given a shape memory property, the above plastic materials or their derivatives having a shape memory property may be used, or a plurality of any of the materials blended in any ratio may also be used.
[0088] The surgical clip of the present invention can be manufactured using a publicly-known resin molding means, for example, it can be manufactured using injection molding or extrusion molding.
[0089] Though the present invention has been described as above, taking resection of a pancreas by way of example, the surgical clip of the present invention is also applicable, in addition to the pancreas, to a liver, a lung, an appendix, and/or an ovary, which are delicate and thick organs like the pancreas. As for the clip of the present invention used in resection of a liver, a lung, an appendix, and/or an ovary, the distance between the inner surfaces of both the arm portions, the length and thickness of the arm portion, the ratio of the hook portion to the arm portion, and the other configurations may be selected appropriately according to the kind of a target organ, the size and state of a portion to be resected, and the other conditions.
EXAMPLE
[0090] The surgical plastic of the present invention was produced in the following manner.
[0091] A mold of the clip was made of silicone rubber. Polycaprolactone whose molecular weight was about 80,000 and which had an excellent elastic modulus was heated to melt, and loaded into the mold. By natural heat dissipation and cooling, a clip having an intended shape was made.
[0092] Using the clip made above, a pancreatectomy was performed on a pig. The abdomen of the pig (a distal pancreatectomy model, two subjects) was opened, and, under visual control, the clip was attached to the body of the pancreas. Thereafter, the tail side was resected by Metzenbaum scissors. A month after the operation, the pig was sacrificed and checked for a pancreatic fistula, and no pancreatic fistula was observed in the abdominal cavity. In addition, a pancreatic portion fixed by the clip of the present invention had been kept in a good state.
INDUSTRIAL APPLICABILITY
[0093] The surgical clip of the present invention can be used to fix a resection stump of a pancreas.
DESCRIPTION OF REFERENCE SIGNS
[0094] 1 . . . first arm portion
[0095] 2 . . . second arm portion
[0096] 3 . . . hinge portion
[0097] 4 . . . hook portion
[0098] 5 . . . curved portion
[0099] 6 . . . distal end of first arm portion
[0100] 7 . . . distal end of second arm portion
[0101] 8, 9 . . . bump-like structure
[0102] 11 . . . inner surface of first arm portion
[0103] 12 . . . outer surface of first arm portion
[0104] 13 . . . inner surface of second arm portion
[0105] 14 . . . outer surface of second arm portion
[0106] 21 . . . space between inner surfaces
[0107] 31, 32 . . . boss portion
[0108] 41, 42 . . . leg portion of applier
[0109] 43, 44 . . . catching mechanism
[0110] 51, 52 . . . leg portion of closer
[0111] 53, 54 . . . receiving portion
[0112] 100 . . . clip
[0113] 400 . . . applier
[0114] 500 . . . closer