A safe exposure device for annulus fibrosus in lumbar posterior surgery

Abstract

The application discloses a kind of annulus fibrosus safe exposure device in lumbar vertebra posterior approach, belong to medical instrument technical field, including barrier ring;The barrier ring is put into lumbar vertebra posterior approach open operation area, to open operating area tissue and isolate nerve root and dural sac with;Suction tube and liquid injection pipe are fixedly connected on the barrier ring;The barrier ring includes rigid ring body;Several liquid suction holes are formed on the inside circumferential curved surface of the rigid ring body, second cavity is arranged between the inside and outside of the rigid ring body, and the liquid suction hole is communicated with the inside of second cavity.Compared with prior art, the annulus fibrosus safe exposure device in lumbar vertebra posterior approach of the application can be safely separated in the periphery of the operation area of nerve root and dural sac, so that the operator can easily and safely carry out nucleus pulposus removal and fusion cage implantation operation.The device can also absorb the bleeding in the operation area in time, avoid the bleeding to block the vision, and bring great convenience to the operator.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a device for safe exposure of the annulus fibrosus during posterior lumbar spine surgery. Background Technology

[0002] During posterior lumbar open surgery for patients with lumbar spondylolisthesis, lumbar spinal stenosis, or lumbar disc herniation, it is usually necessary to use a nerve retractor to retract the dural sac, carefully identify the nerve root, expose the annulus fibrosus of the intervertebral space, remove the nucleus pulposus, and implant an interbody fusion device.

[0003] During this process, the spinal cord dura mater or nerve root can be damaged due to factors such as improper retractor operation by the assistant, bleeding in the surgical area, and unstable instrument operation during the operation, which can lead to serious surgical complications. At the same time, during the nerve retractor traction, local tissues will be compressed for a long time, which can easily cause crush syndrome, resulting in local ischemia or congestion, which may lead to thrombosis, swelling or tissue hypoxia, or even tissue necrosis.

[0004] Therefore, in order to address the above-mentioned technical problems, it is necessary to provide a device for safe exposure of the annulus fibrosus during posterior lumbar spine surgery.

[0005] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a safe annulus fibrosus exposure device for posterior lumbar spine surgery, which can solve the problems of spinal cord dura mater or nerve root damage caused by factors such as improper assistant retractor operation, surgical bleeding, and unstable instrument operation during posterior lumbar open surgery, as well as the problem of compression syndrome caused by prolonged compression of local tissues during retractor traction.

[0007] To achieve the above objectives, a specific embodiment of the present invention provides the following technical solution: A safety exposure device for the annulus fibrosus during posterior lumbar spine surgery, comprising a diaphragm ring; The septum ring is placed in the posterior lumbar open surgery operating area to open the tissue in the operating area and isolate the nerve roots and dural sac; A suction tube and an injection tube are fixedly connected to the baffle ring; The partition ring includes a rigid ring body; A plurality of liquid-absorbing holes are provided on the inner circumferential curved surface of the rigid ring, and a second cavity is provided between the inner and outer sides of the rigid ring, with the liquid-absorbing holes communicating with the interior of the second cavity; One end of the suction tube is connected to the suction device, and the other end is connected to the interior of the second cavity; An outer edge groove is provided on the outer circumferential curved surface of the rigid ring body, and an expansion and contraction component is provided inside the outer edge groove. A first cavity is also provided between the inner and outer sides of the rigid ring body. A control mechanism is installed inside the first cavity, which can control two working states of the expansion and contraction assembly: In the first working state, the control mechanism injects a medium into the expansion and contraction assembly to cause the expansion and contraction assembly to expand to different degrees, thereby regulating the outer diameter of the spacer ring; in the second working state, the control mechanism generates turbulence in the medium inside the expansion and contraction assembly to make the expansion and contraction assembly form a peristaltic effect.

[0008] In one or more embodiments of the present invention, the expansion and contraction assembly includes an external elastic bladder, the external elastic bladder being bonded and fixed inside an outer edge groove, the external elastic bladder having an open annular structure; The external elastic capsule is made of medical-grade silicone.

[0009] In one or more embodiments of the present invention, the control mechanism includes a micro water pump, the input end of which is connected to a medium input pipeline, and the output end of which is connected to a medium output pipeline.

[0010] In one or more embodiments of the present invention, the medium input pipeline includes a first electric three-way valve, the first electric three-way valve including a medium output port and two medium input ports; The medium output port of the first electric three-way valve is connected to the input port of the micro water pump, and the two medium input ports of the first electric three-way valve are respectively fixedly connected to the first inlet pipe and the second inlet pipe. The end of the first inlet pipe away from the first electric three-way valve is connected to the inside of the injection pipe, the end of the injection pipe away from the baffle ring is connected to the medium storage container, and the end of the second inlet pipe away from the first electric three-way valve is connected to the inside of the external elastic bladder.

[0011] In one or more embodiments of the present invention, the medium output pipeline includes a second electric three-way valve, the second electric three-way valve including a medium injection port and two medium discharge ports; The medium injection port of the second electric three-way valve is connected to the output end of the micro water pump, and the two medium discharge ports of the second electric three-way valve are respectively fixedly connected to the first discharge pipe and the second discharge pipe; The end of the first liquid outlet pipe that is away from the second electric three-way valve is connected to one end inside the external elastic bladder, and the second liquid inlet pipe and the first liquid outlet pipe are respectively connected to different ends inside the external elastic bladder.

[0012] In one or more embodiments of the present invention, the medium is physiological saline.

[0013] In one or more embodiments of the present invention, a spray pipe is also fixedly connected to the inner circumferential curved surface of the rigid ring body, and the end of the second outlet pipe away from the second electric three-way valve is connected to one end of the spray pipe.

[0014] In one or more embodiments of the present invention, a plurality of suction tubes are fixedly connected to the inner circumferential surface of the rigid ring body, and the plurality of suction tubes are all connected to the interior of the second cavity.

[0015] In one or more embodiments of the present invention, the suction tube is made of a flexible shape memory alloy, and the inner diameter of the suction tube is smaller than the inner diameter of the suction hole.

[0016] In one or more embodiments of the present invention, the outer surface of the external elastic bladder is provided with a plurality of protrusions.

[0017] Compared with existing technologies, the posterior lumbar spine surgery annulus fibrosus safety exposure device of the present invention can fully and safely isolate the nerve root and dural sac outside the surgical operation area, allowing the surgeon to easily and safely perform nucleus pulposus removal and fusion cage placement. At the same time, the device can promptly absorb bleeding in the surgical area, preventing bleeding from obstructing the field of vision and greatly facilitating the surgeon's operation.

[0018] This invention features a freely variable diameter, which can flexibly adapt to the different surgical needs of different patients. Furthermore, it can move evenly during the operation to achieve the effect of massaging the surrounding tissues, avoiding compression syndrome caused by long-term pressure on local tissues, and improving the safety of the operation and the postoperative recovery effect. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram illustrating the use of a safe exposure device for the annulus fibrosus during posterior lumbar spine surgery according to an embodiment of the present invention; Figure 2 This is the structure of a safe exposure device for the annulus fibrosus during posterior lumbar spine surgery according to one embodiment of the present invention. Figure 1 ; Figure 3 This is a cross-sectional view of the first usage state of a posterior lumbar spine surgery annulus fibrosus safety exposure device according to an embodiment of the present invention; Figure 4This is a cross-sectional view of the second usage state of a posterior lumbar spine surgery annulus fibrosus safety exposure device according to an embodiment of the present invention; Figure 5 This is the structure of a safe exposure device for the annulus fibrosus during posterior lumbar spine surgery according to one embodiment of the present invention. Figure 2 ; Figure 6 This is a bottom sectional view of a device for safe exposure of the annulus fibrosus during posterior lumbar spine surgery according to an embodiment of the present invention; Figure 7 This invention provides a device for safe exposure of the annulus fibrosus during posterior lumbar spine surgery. Figure 6 Enlarged view of point A in the middle; Figure 8 This is the structure of a safe exposure device for the annulus fibrosus during posterior lumbar spine surgery according to one embodiment of the present invention. Figure 3 .

[0021] Explanation of key figure labels: 10. Baffle ring; 11. Rigid ring body; 111. Liquid suction hole; 112. Outer edge groove; 113. First cavity; 114. Second cavity; 12. External elastic bladder; 121. Protrusion; 13. Liquid suction tube; 14. Liquid spraying tube; 15. First electric three-way valve; 151. First liquid inlet tube; 152. Second liquid inlet tube; 16. Miniature water pump; 17. Second electric three-way valve; 171. First liquid outlet tube; 172. Second liquid outlet tube; 20. Suction tube; 30. Liquid injection tube. Detailed Implementation

[0022] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.

[0023] like Figures 1-8 As shown in one embodiment of the present invention, a safe exposure device for the annulus fibrosus during posterior lumbar spine surgery includes a septum ring 10. During open posterior lumbar spine surgery, the septum ring 10 can be placed in the surgical area to open the tissues in the surgical area and isolate the nerve roots and dural sac. This effectively and safely isolates the nerve roots and dural sac outside the surgical area, allowing the surgeon to easily and safely perform nucleus pulposus removal and fusion device placement. It avoids damage to the spinal cord, dural sac, or nerve roots caused by factors such as improper retractor operation by the assistant, bleeding in the surgical area, or unstable instrument operation during surgery, thus improving the safety and success rate of the surgery.

[0024] like Figure 2 and Figure 3 As shown, a suction tube 20 and an injection tube 30 are fixedly connected to the septum 10. The end of the suction tube 20 away from the septum 10 is connected to a negative pressure suction device so as to remove bleeding in the surgical area through the septum 10. The end of the injection tube 30 away from the septum 10 is connected to a saline storage container so that saline can be drawn through the injection tube 30 as a medium to control the expansion and contraction of the external elastic bladder 12.

[0025] Specifically, the baffle ring 10 includes a rigid ring body 11. Several suction holes 111 are formed on the inner circumferential curved surface of the rigid ring body 11, all located near the bottom, to facilitate timely removal of bleeding from the surgical area. A second cavity 114 is provided between the inner and outer sides of the rigid ring body 11, and the suction holes 111 communicate with the interior of the second cavity 114. The end of the suction tube 20 near the baffle ring 10 is also connected to the interior of the second cavity 114.

[0026] During operation, the septum ring 10 is placed in the surgical area. Bleeding during the operation can be sucked into the second cavity 114 through several suction holes 111, and then extracted by the negative pressure suction device through the suction tube 20. This timely absorption of bleeding in the surgical area avoids bleeding from obstructing the field of vision and helps to improve the success rate of nucleus pulposus removal and fusion device placement.

[0027] It is worth noting that multiple sets of suction tubes 13 are also fixedly connected to the inner circumferential surface of the rigid ring 11, and all sets of suction tubes 13 are connected to the interior of the second cavity 114. The surgeon can manually operate the suction tubes 13 to precisely and efficiently aspirate bleeding from designated areas, preventing continuous bleeding from affecting the surgical procedure.

[0028] The suction tube 13 is made of flexible shape memory alloy, which can be deformed arbitrarily and maintain its shape, making it more convenient and stable to use. At the same time, the inner diameter of the suction tube 13 is smaller than the inner diameter of the suction hole 111, ensuring that blood can be smoothly drawn from the designated site through the suction tube 13.

[0029] An outer edge groove 112 is formed on the outer circumferential curved surface of the rigid ring body 11, and an expansion and contraction component is provided inside the outer edge groove 112. The expansion and contraction component includes an external elastic bladder 12, which is bonded and fixed inside the outer edge groove 112. The external elastic bladder 12 has an open ring structure, and its two ends are not connected to allow for subsequent control of the peristaltic effect.

[0030] The external elastic bladder 12 is made of medical-grade silicone, which meets medical and health needs while having good expansion and contraction performance, making it safe and reliable to use.

[0031] At work, such as Figure 3 and Figure 4As shown, the outer diameter of the septum 10 can be adjusted by injecting saline solution into the external elastic bladder 12 and controlling the amount of saline solution injected, thereby allowing the septum 10 to flexibly change diameter to meet the different surgical needs of different patients.

[0032] A first cavity 113 is also provided between the inner and outer sides of the rigid ring 11. The first cavity 113 is located above the second cavity 114, and the first cavity 113 and the second cavity 114 are independent of each other. A control mechanism is installed inside the first cavity 113, which can control two working states of the expansion and contraction assembly: In the first working state, the control mechanism injects a medium into the expansion and contraction assembly to cause the expansion and contraction assembly to expand to different degrees, thereby regulating the outer diameter of the baffle ring 10; in the second working state, the control mechanism generates turbulence in the medium inside the expansion and contraction assembly to make the expansion and contraction assembly form a creeping effect.

[0033] Specifically, such as Figure 6 and Figure 7 As shown, the control mechanism includes a miniature water pump 16, which is fixedly installed inside the first cavity 113. The input end of the miniature water pump 16 is connected to a medium input pipeline, and the output end of the miniature water pump 16 is connected to a medium output pipeline. The miniature water pump 16 can draw physiological saline through the medium input pipeline and inject it into the external elastic bladder 12 through the medium output pipeline.

[0034] The medium input pipeline includes a first electric three-way valve 15, which has one medium output port and two medium input ports. The medium output port of the first electric three-way valve 15 is connected to the input end of the micro water pump 16, and the two medium input ports of the first electric three-way valve 15 are respectively fixedly connected to a first inlet pipe 151 and a second inlet pipe 152.

[0035] The end of the first inlet pipe 151 furthest from the first electric three-way valve 15 is connected to the inside of the injection pipe 30, allowing the miniature water pump 16 to sequentially draw saline solution from the storage container through the first inlet pipe 151 and the injection pipe 30. Additionally, the end of the second inlet pipe 152 furthest from the first electric three-way valve 15 is connected to the inside of the external elastic bladder 12, enabling the miniature water pump 16 to draw saline solution from inside the external elastic bladder 12 through the second inlet pipe 152. The extraction path of the saline solution can be flexibly controlled via the first electric three-way valve 15.

[0036] The media output pipeline includes a second electric three-way valve 17, which includes one media injection port and two media discharge ports. The media injection port of the second electric three-way valve 17 is connected to the output end of the micro water pump 16, and the two media discharge ports of the second electric three-way valve 17 are respectively fixedly connected to a first outlet pipe 171 and a second outlet pipe 172.

[0037] One end of the first outlet tube 171, away from the second electric three-way valve 17, is connected to one end inside the external elastic bladder 12, so that the saline solution drawn by the micro water pump 16 can be injected into the external elastic bladder 12 through the first outlet tube 171.

[0038] In addition, such as Figures 5-7 As shown, a spray pipe 14 is also fixedly connected to the inner circumferential surface of the rigid ring 11, and the end of the second outlet pipe 172 away from the second electric three-way valve 17 is connected to one end of the spray pipe 14. This allows the saline solution drawn by the micro water pump 16 to enter the interior of the spray pipe 14 through the second outlet pipe 172 and be sprayed out through the spray pipe 14 to clean the surgical area.

[0039] The discharge path of the saline solution drawn by the micro water pump 16 can be flexibly controlled by the second electric three-way valve 17.

[0040] During initial operation, the saline extraction path is adjusted via the first electric three-way valve 15 to the injection tube 30 to the first inlet tube 151, and the saline discharge path is adjusted via the second electric three-way valve 17 to the first outlet tube 171 to the interior of the external elastic sac 12. At this time, the micro water pump 16 continuously draws saline from the storage container and injects it into the external elastic sac 12, causing it to expand outwards. The expansion size of the external elastic sac 12 is controlled according to surgical needs to obtain the required size of the septum 10. The septum 10 is placed within the surgical operating area to effectively expand the surgical space and efficiently isolate the nerve root and dural sac outside the surgical operating area.

[0041] During the surgery, to prevent the diaphragm 10 from supporting and compressing the surrounding local tissues for an extended period, the saline extraction path is adjusted via the first electric three-way valve 15 to run from one end of the external elastic bladder 12 to the second inlet tube 152, while the saline discharge path remains unchanged. Since the second inlet tube 152 and the first outlet tube 171 are connected to different ends of the external elastic bladder 12, a passage is formed between the two ends of the external elastic bladder 12. The micro-pump 16 can then extract saline from one end of the external elastic bladder 12 via the second inlet tube 152 and inject it into the other end via the first outlet tube 171. By intermittently or stepwise activating the micro-pump 16, a portion of saline can be extracted from one end of the external elastic bladder 12 and injected into the other end at regular intervals. This creates turbulence within the external elastic capsule 12, causing it to undergo gradual deformation and thus producing a peristaltic effect. This peristaltic movement continuously massages the surrounding tissues, ensuring normal blood flow and effectively preventing ischemia, hypoxia, or even tissue necrosis caused by prolonged pressure. It also prevents adhesion between the surrounding tissues and the surface of the external elastic capsule 12, improving surgical safety, promoting postoperative tissue growth and healing, and ensuring a better recovery.

[0042] It is worth noting that during the peristalsis of the external elastic capsule 12, it can continuously massage the nerve root and dural sac, preventing nerve necrosis and dural sac damage caused by compression, and further improving the success rate of the surgery.

[0043] More noteworthy is that, such as Figure 8 As shown, the outer surface of the external elastic bladder 12 is provided with several protrusions 121, which can significantly improve the massage effect of the external elastic bladder 12 during peristalsis.

[0044] Additionally, during the procedure, it is unavoidable to clean the surgical area to remove residual, poorly flowing blood. At this time, the saline solution extraction path can be adjusted again via the first electric three-way valve 15 to connect the injection tube 30 to the first inlet tube 151, and the saline solution discharge path can be adjusted via the second electric three-way valve 17 to connect the second outlet tube 172 to the spray tube 14. Saline solution can then be drawn from the storage container and sprayed into the surgical area through the spray tube 14 to rinse away any remaining blood and prevent it from obstructing the view. No other tools are needed, and the spray tube 14 can also be made of flexible shape-memory alloy, allowing the surgeon to manually control its shape. It maintains the desired form for continuous and precise rinsing of the designated area, making it more convenient to use.

[0045] In addition, the waste liquid generated during rinsing can be extracted by several suction holes 111 or suction tubes 13, effectively preventing the waste liquid from overflowing and eliminating the need for additional cleaning, which greatly facilitates the surgical procedure.

[0046] The posterior lumbar spine surgery annulus fibrosus safety exposure device of the present invention can fully and safely isolate the nerve root and dural sac outside the surgical operation area, allowing the surgeon to easily and safely perform nucleus pulposus removal and fusion cage placement. At the same time, the device can promptly absorb bleeding in the surgical area, preventing bleeding from obstructing the field of vision and greatly facilitating the surgeon's operation.

[0047] This invention features a freely variable diameter, which can flexibly adapt to the different surgical needs of different patients. Furthermore, it can move evenly during the operation to achieve the effect of massaging the surrounding tissues, avoiding compression syndrome caused by long-term pressure on local tissues, and improving the safety of the operation and the postoperative recovery effect.

[0048] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0049] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A safety exposure device for the annulus fibrosus during posterior lumbar spine surgery, characterized in that, include: A septum ring is placed in the posterior lumbar open surgery operating area to open the tissues in the operating area and isolate the nerve roots and dural sac; A suction tube and an injection tube are fixedly connected to the baffle ring; The spacer ring includes: A rigid ring body, wherein a plurality of liquid absorption holes are formed on the inner circumferential curved surface of the rigid ring body, and a second cavity is provided between the inner and outer sides of the rigid ring body, and the liquid absorption holes are connected to the interior of the second cavity; One end of the suction tube is connected to the suction device, and the other end is connected to the interior of the second cavity; An outer edge groove is provided on the outer circumferential curved surface of the rigid ring body, and an expansion and contraction component is provided inside the outer edge groove. The expansion and contraction assembly includes an external elastic bladder, which is bonded and fixed inside the outer edge groove, and the external elastic bladder has an open annular structure. The external elastic capsule is made of medical-grade silicone. A first cavity is also provided between the inner and outer sides of the rigid ring body. A control mechanism is installed inside the first cavity, which can control two working states of the expansion and contraction assembly: In the first working state, the control mechanism injects a medium into the expansion and contraction assembly to cause the expansion and contraction assembly to expand to different degrees, thereby regulating the outer diameter of the baffle ring; in the second working state, the control mechanism generates turbulence in the medium inside the expansion and contraction assembly to make the expansion and contraction assembly form a peristaltic effect. The control mechanism includes a micro water pump, the input end of which is connected to a medium input pipeline, and the output end of which is connected to a medium output pipeline. The medium input pipeline includes a first electric three-way valve, which includes one medium output port and two medium input ports. The medium output port of the first electric three-way valve is connected to the input port of the micro water pump, and the two medium input ports of the first electric three-way valve are respectively fixedly connected to the first inlet pipe and the second inlet pipe. The end of the first inlet pipe away from the first electric three-way valve is connected to the inside of the injection pipe, the end of the injection pipe away from the baffle ring is connected to the medium storage container, and the end of the second inlet pipe away from the first electric three-way valve is connected to the inside of the external elastic bladder. The medium output pipeline includes a second electric three-way valve, which includes a medium injection port and two medium discharge ports. The medium injection port of the second electric three-way valve is connected to the output end of the micro water pump, and the two medium discharge ports of the second electric three-way valve are respectively fixedly connected to the first discharge pipe and the second discharge pipe; The end of the first liquid outlet pipe away from the second electric three-way valve is connected to one end inside the external elastic bladder, and the second liquid inlet pipe and the first liquid outlet pipe are respectively connected to different ends inside the external elastic bladder. During initial operation, the medium extraction path is adjusted by the first electric three-way valve to the injection pipe to the first inlet pipe, and the medium discharge path is adjusted by the second electric three-way valve to the outlet pipe to the inside of the external elastic bladder. During the procedure, the extraction path of the medium is adjusted by the first electric three-way valve to one end of the external elastic bladder to the second inlet pipe, while the discharge path of the medium remains unchanged. The two ends of the external elastic bladder form a passage through the second inlet pipe and the first outlet pipe. The micro water pump can extract the medium from one end of the external elastic bladder through the second inlet pipe and then inject it into the other end of the external elastic bladder through the first outlet pipe.

2. The device for safe exposure of the annulus fibrosus during posterior lumbar spine surgery according to claim 1, characterized in that, The medium is physiological saline.

3. The posterior lumbar spine surgery annulus fibrosus safety exposure device according to claim 2, characterized in that, A spray pipe is also fixedly connected to the inner circumferential curved surface of the rigid ring body, and the end of the second outlet pipe away from the second electric three-way valve is connected to one end of the spray pipe.

4. A safe exposure device for the annulus fibrosus during posterior lumbar spine surgery according to claim 1, characterized in that, Multiple sets of suction tubes are also fixedly connected to the inner circumferential curved surface of the rigid ring, and all sets of suction tubes are connected to the interior of the second cavity.

5. A safe exposure device for the annulus fibrosus during posterior lumbar spine surgery according to claim 4, characterized in that, The suction tube is made of flexible shape memory alloy, and the inner diameter of the suction tube is smaller than the inner diameter of the suction hole.

6. A safe exposure device for the annulus fibrosus during posterior lumbar spine surgery according to claim 1, characterized in that, The outer surface of the external elastic bladder is provided with several protrusions.

Images