Epidural electrical stimulation device

Abstract

The invention discloses an epidural electrical stimulation device which comprises a carrier configured to be in a rod shape and provided with a far end and a near end; the stimulation array comprises a plurality of electrical stimulation units, and the plurality of electrical stimulation units are sequentially arranged on the carrier in the axial direction; each electrical stimulation unit comprises a sheet-shaped elastic substrate attached to the carrier and a sheet-shaped flexible electrode attached to the outer side surface of the elastic substrate; the pulse generator is used for providing pulse current for the flexible electrode; the catheter is arranged outside the carrier in a sleeving manner, and the catheter is provided with a far end and a near end which are consistent with the carrier; the elastic substrate has a folded state in which the elastic substrate wraps the outer peripheral surface of the carrier through elastic deformation and an unfolded state in which the elastic substrate is bent reversely through elastic reset, and the guide pipe axially moves relative to the carrier so that the elastic substrate can be switched to the folded state or the unfolded state.

Description

Technical Field

[0001] The present invention relates to the technical field of spinal cord electrical stimulation, and in particular to a device for performing electrical stimulation on the spinal cord outside the dura mater. Background Art

[0002] Epidural electrical stimulation of the spinal cord has been shown to be effective in treating symptoms such as chronic pain and limb paralysis associated with spinal cord injury. The typical electrical stimulation method is to insert an electrode into the spinal canal of the spine through the space between vertebrae, so that the electrode contacts the dura mater of the spinal cord to perform electrical stimulation.

[0003] An electrical stimulation device for epidural electrical stimulation of the spinal cord generally comprises: a carrier extending at least in the axial direction, a stimulation array attached to the carrier and having a plurality of electrodes arranged along the axial direction, and a pulse generator for providing pulse current to the electrodes so that the electrodes can electrically stimulate the spinal cord.

[0004] The contact area between the electrode and the dura mater of the spinal cord is a key factor affecting the effect of electrical stimulation therapy. In a typical electrical stimulation device, the carrier is configured in a rod shape, and the electrodes in the stimulation array are coated on the cylindrical surface of the carrier. Since the dura mater of the spinal cord is also basically wrapped in a cylindrical surface, the electrode and the dura mater are only in contact through the arc surface, and the contact area is very small, resulting in poor electrical stimulation effect of the electrode on the spinal cord; in another typical electrical stimulation device, the carrier is configured in a paddle shape (or strip shape). Therefore, this type of structural carrier has a flat surface, and the electrodes in the stimulation array are attached On the surface of the carrier, the electrode contacts the dura mater through the flat surface and the curved surface, so that the contact area between the electrode on the paddle-shaped carrier and the dura mater is increased compared with the contact area of ​​the electrode on the rod-shaped carrier, but the increase in the contact area is not large. However, the movement of the paddle-shaped carrier in the spinal canal is limited compared with the rod-shaped carrier. For example, the rod-shaped carrier is more easily dragged along the spinal canal, and is not easy to injure the dura mater, spinal cord and peripheral tissues when being dragged, while the paddle-shaped carrier is not easily dragged along the spinal canal, and the risk of injuring related tissues when being dragged is increased.

[0005] After the stimulation array is placed in a suitable position in the spinal canal, the stability of the position of the carrier is also a key factor affecting the long-term treatment effect of electrical stimulation. If the carrier cannot be positioned, the stimulation array may shift with the carrier, resulting in poor electrical stimulation effect or even failure. In order to achieve the positioning of the carrier, in the prior art, multiple anchoring components are arranged axially on the carrier (for example, Chinese patent No. 201910339477.5 provides a carrier with anchoring components), and the anchoring components are in close contact with the surrounding related tissues by expansion, thereby achieving the positioning of the carrier. However, the significant defect of the anchoring components provided in the prior art is that the anchoring components are not only in close contact with the wall of the spinal canal, but also in contact with the dura mater at the same time, which not only causes local compression of the dura mater, but also makes it difficult for the electrode to be attached to the outside of the dura mater due to the support of the anchoring components on the carrier. Summary of the invention

[0006] In view of the above-mentioned technical problems existing in the prior art, an embodiment of the present invention provides an epidural electrical stimulation device.

[0007] In order to solve the above technical problems, the technical solution adopted in the embodiments of the present invention is: An epidural electrical stimulation device, comprising: A carrier configured in a rod shape, the carrier having a distal end for entering the spinal canal of the spine through the space between vertebrae and a proximal end retained outside the body; A stimulation array, comprising a plurality of electrical stimulation units, which are arranged on the carrier in sequence along the axial direction from the distal end of the carrier; each of the electrical stimulation units comprises a sheet-shaped elastic substrate attached to the carrier and a sheet-shaped flexible electrode attached to the outer surface of the elastic substrate; A pulse generator, which provides a pulse current for implementing electrical stimulation to the flexible electrode of each electrical stimulation unit through a wire; A catheter is sleeved outside the carrier and can move axially relative to the carrier, and the catheter has a distal end and a proximal end consistent with the carrier; wherein: The elastic base has a folded state in which it is wrapped around the outer peripheral surface of the carrier by elastic deformation, and an expanded state in which it is reversely bent by elastic restoration; The elastic base is forced to switch to a retracted state by moving the distal end of the catheter toward the distal end of the carrier, and the elastic base is released by moving the distal end of the catheter in a direction away from the distal end of the carrier. The elastic base is reversely bent by elastic resetting to switch to an expanded state, so that after the carrier enters the spinal canal, the elastic base switches to the expanded state so that the flexible electrode contacts the dura mater of the spinal cord.

[0008] Preferably, The elastic base has a middle area and side walls symmetrically arranged on both sides of the middle area in a circumferential direction, and the elastic base is attached to the carrier in the middle area; the two side walls are elastically deformed to switch the elastic base to a retracted state, and the side walls are elastically reset to switch the elastic base to an expanded state; The two side edges of the side wall in the circumferential direction are configured to be relatively inclined or the distal end of the conduit is configured to have an inclined end surface.

[0009] Preferably, the epidural electrical stimulation device further comprises an anchor array, the anchor array comprising a plurality of anchor units, the plurality of anchor units are arranged on the carrier at intervals along the axial direction, and the anchor units are arranged at circumferential positions opposite to the electrical stimulation units; The anchoring unit has a collapsed state formed by elastic deformation and an expanded state formed by elastic resetting to radially protrude; The anchoring unit is forced to switch to a retracted state by moving the distal end of the catheter toward the distal end of the carrier, and the anchoring unit is released and switched to an expanded state by moving the distal end of the catheter away from the distal end of the carrier. Thus, after the carrier enters the spinal canal, the anchoring unit is switched to an expanded state and abuts against the posterior wall of the spinal canal.

[0010] Preferably, each of the anchoring units includes a support unit formed by two elastic wires bent into a trapezoidal shape, the two support units are symmetrically arranged, the support unit is wrapped around the carrier by bending toward the carrier, so that the anchoring unit switches to a retracted state, the support unit is bent in the opposite direction by elastic resetting to abut against the posterior wall of the spinal canal, so that the anchoring unit switches to an expanded state, and after switching to the expanded state, the two support units are separated from each other at an angle.

[0011] Preferably, a notch extending axially is configured at a circumferential position corresponding to the middle area of ​​the catheter and the elastic base, and the catheter on both sides of the notch forms a thickness weakened portion, and the notch exposes the flexible electrode so that the flexible electrode can contact the dura mater when the catheter is not separated from the carrier.

[0012] Preferably, The carrier is formed by bending the strips, so that the carrier has a central channel, and the two sides of the strips define a slot after the carrier is bent; Before the slat is bent, the wire is arranged along one side surface of the slat, and the wire contacts at the ends of the wire are arranged on the end walls of the two sides of the slat, so that after the slat is bent into a carrier, the wire contacts are located on the two slot walls of the slot; The middle area of ​​the elastic base is provided with a convex strip, the wall of the convex strip is provided with an electrode contact electrically connected to the flexible electrode, and the convex strip is inserted into the slot and bonded, so that the electrode contact is electrically connected to the wire contact.

[0013] Preferably, a plurality of skeletons arranged axially at intervals are embedded in the tube wall of the catheter; a guide strip extending axially is arranged at a circumferential position of the inner wall of the catheter opposite to the notch, and a guide groove extending axially is arranged on the carrier on the opposite side of the electric stimulation unit, and the guide strip cooperates with the guide groove to limit the twisting of the catheter in the circumferential direction relative to the carrier.

[0014] Preferably, a developing strip extending in the axial direction is arranged on the outer peripheral surface of the guide tube.

[0015] Preferably, the outer peripheral surface of the carrier is configured as an elliptical cylinder; the electrical stimulation unit and the anchoring unit are respectively located on both sides of the end axis of the elliptical cylinder.

[0016] Preferably, both ends of the elastic thread are fixed to the carrier by plugging and bonding.

[0017] Compared with the prior art, the epidural electrical stimulation device provided by the embodiment of the present invention has the following beneficial effects: The catheter, stimulation array, anchoring unit and carrier cooperate with each other so that the carrier enters the spinal canal in a smaller outer diameter state, and after the catheter is withdrawn from the carrier, the electrical stimulation units of the stimulation array switch to the expanded state and reversely wrap around the outside of the spinal cord, so that the flexible electrodes on the carrier in the present invention obtain a larger contact area with the dura mater than the electrodes on the carrier in the prior art. The anchoring unit switches to the expanded state to achieve positioning of the carrier, so that the position of the electrical stimulation units on the carrier remains stable, which is conducive to the flexible electrodes to implement long-term electrical stimulation of the spinal cord. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In the drawings, which are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The same reference numerals with letter suffixes or different letter suffixes may represent different instances of similar parts. The accompanying drawings generally illustrate various embodiments by way of example and not limitation, and together with the specification and claims, are used to illustrate the embodiments of the invention. When appropriate, the same reference numerals are used throughout the drawings to refer to the same or similar parts. Such embodiments are illustrative and are not intended to be exhaustive or exclusive embodiments of the present apparatus or method.

[0019] Figure 1 This is a view of a state where the carrier in the electrical stimulation device provided by the present invention is covered by a catheter.

[0020] Figure 2 for Figure 1 An enlarged view of detail A.

[0021] Figure 3 This is a cross-sectional view of the carrier in the electrical stimulation device provided by the present invention when being covered by a catheter.

[0022] Figure 4 This is a view of the state after the carrier in the electrical stimulation device provided by the present invention is released by the catheter.

[0023] Figure 5 for Figure 4 An enlarged view of detail B.

[0024] Figure 6 This is a schematic diagram of the structure of the catheter in the electrical stimulation device provided by the present invention.

[0025] Figure 7 This is a view of the state in which the carrier of the electrical stimulation device provided by the present invention enters the spinal canal cavity of the human body.

[0026] Figure 8 for Figure 7 An enlarged view of partial C (the catheter brings the electrical stimulation unit and the anchoring unit into a retracted state).

[0027] Fig. 9 for Figure 7 An enlarged view of partial C (the state after the catheter releases the electrical stimulation unit and the anchoring unit).

[0028] In the figure: 10-carrier; 11-slot; 12-guide groove; 20-stimulation array; 21-electric stimulation unit; 211-flexible electrode; 212-elastic base; 2121-side wall; 2122-convex strip; 30-anchoring array; 31-anchoring unit; 311-elastic wire; 40-catheter; 41-notch; 42-skeleton; 43-thickness reduction part; 44-guide strip; 50-wire; 60-pulse generator; 101-vertebra; 102-spinal canal; 103-dura mater; 104-spinal cord. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0031] In order to keep the following description of the embodiments of the present invention clear and concise, detailed descriptions of well-known functions and well-known components are omitted.

[0032] An embodiment of the present invention discloses an epidural electrical stimulation device, such as Figure 1 As shown, the epidural electrical stimulation device is used to electrically stimulate the spinal cord 104 in the spinal canal 102 of the spine. Specifically, the electrodes in the device are outside the dura mater 103 of the spinal cord 104 to electrically stimulate the spinal cord 104. The electrical stimulation device provided by the present invention can not only perform short-term electrical stimulation on the spinal cord 104, for example, perform short-term electrical stimulation treatment on the spinal cord 104 in a hospital treatment site, but also perform long-term electrical stimulation (or permanent electrical stimulation) on the spinal cord 104, for example, the patient can carry the device for a long time and obtain long-term electrical stimulation treatment in a non-treatment site.

[0033] like Figure 7 Combined with Figures 1 to 5 As shown, the electrical stimulation device provided by the present invention includes: a carrier 10, a stimulation array 20, an anchoring array 30, a pulse generator 60 and a catheter 40.

[0034] The carrier 10 is used to deliver the stimulation array 20 from outside the body to the spinal canal 102 of the spine. The carrier 10 is configured in a rod shape, that is, the cross section of the carrier 10 is circular or approximately circular, such as an elliptical shape, and the carrier 10 has a size in the axial direction that is much larger than that in the radial direction. The carrier 10 has a proximal end located on the operator's side and a distal end away from the operator's side in the axial direction. In the process of delivering the stimulation array 20 to the spinal canal 102, the distal end of the carrier 10 first enters the spinal canal 102 through the gap between the posterior sides of the vertebrae 101, and then the carrier 10 is pushed axially, such as Figure 7As shown, the shaft section of the carrier 10 attached with the stimulation array 20 is entered into the spinal canal 102 , while the proximal end of the carrier 10 is located outside the body for attaching the cable of the pulse generator 60 .

[0035] The carrier 10 is configured to have a certain rigidity so that the carrier 10 always remains in a straight line or a nearly straight line state, and the carrier 10 is configured as an insulator to prevent the pulse current applied by the stimulation array 20 from being weakened and to prevent the pulse current from being applied to tissues other than the spinal cord 104. The carrier 10 can be made of a polymer material to meet the rigidity and insulation requirements of the carrier 10, and a polymer such as polyurethane with good mechanical properties and biocompatibility is selected to make the carrier 10.

[0036] like Figure 1 As shown, the stimulation array 20 includes a plurality of electrical stimulation units 21, and the plurality of electrical stimulation units 21 are arranged in sequence along the axial direction from the distal end to the proximal end of the carrier 10. Each electrical stimulation unit 21 includes a sheet-like elastic substrate 212 and a sheet-like flexible electrode 211 attached to the outer surface of the elastic substrate 212. The flexible electrode 211 is electrically connected to a wire 50 extending from the proximal end of the carrier 10 to the electrical stimulation unit 21. The wire 50 is electrically connected to a cable of a pulse generator 60 at the proximal end of the carrier 10, so that the flexible electrode 211 is electrically connected to the pulse generator 60, so that the flexible electrode 211 can obtain a pulse current from the pulse generator 60. Figure 3 Combined with Figure 2 and Figure 5 As shown, the elastic base 212 has a middle area and side walls 2121 on both sides of the middle area in the circumferential direction. The middle area is bonded and fixed to the carrier 10, so that the electrical stimulation unit 21 is attached to the carrier 10, and the middle areas of the elastic bases 212 of all the electrical stimulation units 21 are attached to the same circumferential position of the carrier 10. When the carrier 10 enters the spinal canal 102, the circumferential position is directed toward the spinal cord 104. This circumferential position may be referred to as the anterior circumferential position. Therefore, the position on the carrier 10 opposite to the middle area is the posterior circumferential position, and the posterior circumferential position is used to face the posterior wall of the spinal canal 102.

[0037] The elastic base 212 is configured to have the following deformation characteristics: Figure 5 As shown, in the natural state, the side wall 2121 is in a reverse bending state relative to the carrier 10, and the curvature of the reverse bending is slightly less than or substantially equal to the curvature of the cylinder enveloped by the dura mater 103 of the spinal cord 104. Under the contraction effect (i.e., the side wall 2121 is bent toward the carrier 10), as shown in FIG. Figure 2As shown, the side wall 2121 is elastically deformed and bent toward the carrier 10 and can be wrapped around the outside of the cylindrical surface of the carrier 10. Since the side wall 2121 is in an elastic deformation state when it wraps around the carrier 10, the side wall 2121 will bend in the reverse direction again through elastic reset after the retraction effect is cancelled. The state of the elastic base 212 and the electrical stimulation unit 21 when the side wall 2121 is wrapped around the outside of the carrier 10 may be called the retracted state, and the state of the elastic base 212 and the electrical stimulation unit 21 when the side wall 2121 is in the reverse bending may be called the unfolded state.

[0038] The elastic base 212 can be made of a polymer material, for example, the same polymer material as that used to make the carrier 10 can be selected, specifically, a polymer such as polyurethane. The elastic base 212 can be made by the following process: a polyurethane sheet is selected, then the polyurethane sheet is cut, and then the sheet is bent under heating conditions, so that the elastic base 212 is in a reverse bending state opposite to the contracted state under natural conditions (i.e., without external force).

[0039] like Figure 1 and Figure 2 as well as Figure 4 and Figure 5 As shown, the anchor array 30 includes a plurality of anchor units 31, which are sequentially arranged axially from the distal end of the carrier 10 and attached to the carrier 10, and all the anchor units 31 are located at the rear circumferential position of the carrier 10, so that Figure 8 As shown, after the carrier 10 is delivered into the spinal canal 102 with the stimulation array 20 facing the spinal cord 104, all anchoring units 31 face the back wall of the spinal canal 102. At this time, the stimulation array 20 and the anchoring array 30 are located at the front and back sides of the carrier 10 respectively.

[0040] Each anchoring unit 31 is configured to have the following deformation characteristics: Figure 2 As shown, in the natural state, the anchoring unit 31 is in a state of radially protruding backwards, which may be referred to as the expansion state of the anchoring unit 31. Figure 5 As shown, under the retraction effect (i.e., the anchoring unit 31 is retracted toward the carrier 10), the anchoring unit 31 can basically not protrude from the cylindrical surface of the carrier 10 while undergoing elastic deformation. This state may be referred to as the retracted state of the anchoring unit 31.

[0041] In some preferred structures, the anchoring unit 31 is configured as follows: The anchoring unit 31 includes two support units symmetrically arranged in the circumferential direction. Each support unit is formed by bending an elastic wire 311 into a trapezoid. When the anchoring unit 31 is in an expanded state, the two support units protrude radially backwards, and there is a certain angle between the two support units. Under the action of contraction, the two support units bend in the opposite direction and cover the outer peripheral surface of the carrier 10. In this way, after the carrier 10 is sent into the spinal canal 102 with the stimulation array 20 toward the spinal cord 104, and the anchoring component is switched to the expanded state by releasing the anchoring component, as shown in FIG. Fig. 9 As shown, the two supporting units of each anchoring unit 31 are supported on the relevant tissues of the posterior wall of the spinal canal 102 (eg, vertebral 101 tissues, muscle tissues at the gap between vertebrae 101) in an angled manner.

[0042] The elastic wire 311 of the anchoring unit 31 can be made of an alloy material or a high molecular polymer material with good biocompatibility. Preferably, titanium alloy wire is selected as the elastic wire 311, so that both ends of the elastic wire 311 are inserted into the prefabricated sockets at the rear circumferential position of the carrier 10 and bonded with medical adhesive.

[0043] like Figure 1 , Figure 3 , Figure 6 As shown, the catheter 40 has a distal end and a proximal end consistent with the carrier 10, and both the proximal end and the distal end of the catheter 40 are open ports. The catheter 40 is detachably mounted on the carrier 10, and the specific assembly method of the catheter 40 and the carrier 10 is as follows: the proximal end of the carrier 10 is inserted into the distal end of the catheter 40, and the catheter 40 is pushed toward the distal end of the carrier 10 so that the catheter 40 moves axially relative to the carrier 10 and finally the carrier 10 is covered by the catheter 40; the catheter 40 is dragged in the distal direction away from the carrier 10 so that the distal end of the catheter 40 is away from the distal end of the carrier 10, so that the catheter 40 is finally completely detached from the carrier 10 from the rear end of the carrier 10.

[0044] In the process of pushing the catheter 40 toward the distal end of the carrier 10 so that the catheter 40 gradually covers the carrier 10, the distal end of the catheter 40 produces a contraction effect on the electrical stimulation unit 21 and the anchoring unit 31 at the corresponding axial position, thereby forcing the electrical stimulation unit 21 and the anchoring unit 31 to bend in the opposite direction and switch to a contraction state covered on the cylindrical surface of the carrier 10. In this way, when the carrier 10 is completely covered by the catheter 40, the catheter 40 forces the electrical stimulation unit 21 and the anchoring unit 31 to be in a contraction state restricted by the catheter 40, so that the radial size of the carrier 10 covered with the catheter 40 is smaller, such as Figure 8 As shown, the carrier 10 is delivered into the spinal canal 102 in a state of being covered by the catheter 40 .

[0045] After the carrier 10 is delivered into the spinal canal 102 in a state covered by the catheter 40 and with the stimulation array 20 directed toward the spinal cord 104, the catheter 40 is dragged in a direction away from the distal end of the carrier 10. During this process, the carrier 10 is continuously exposed by the catheter 40 from the distal end to the proximal end, and the electrical stimulation unit 21 and the anchoring unit 31 on the carrier 10 are released by the catheter 40. The elastic base 212 of the electrical stimulation unit 21 is bent in the opposite direction and switched to an extended (expanded) state, so that the elastic base 212 and the flexible electrode 211 are covered on the outside of the dura mater 103 of the spinal cord 104, and the two supporting units of the anchoring unit 31 are supported on the posterior wall of the spinal canal 102 by resetting the radial protrusion.

[0046] The catheter 40, the stimulation array 20, the anchoring unit 31 and the carrier 10 cooperate with each other so that the carrier 10 enters the spinal canal 102 with a smaller outer diameter. After the catheter 40 withdraws from the carrier 10, the electrical stimulation units 21 of the stimulation array 20 switch to the expanded state and reversely wrap around the outside of the spinal cord 104, so that the flexible electrode 211 on the carrier 10 of the present invention obtains a larger contact area with the dura mater 103 than the electrode on the carrier 10 in the prior art. The anchoring unit 31 switches to the expanded state to achieve positioning of the carrier 10, so that the position of the electrical stimulation unit 21 on the carrier 10 remains stable, which is conducive to the flexible electrode 211 to implement long-term electrical stimulation of the spinal cord 104.

[0047] In some preferred structures, such as Fig. 9 As shown, the anchoring units 31 and the electrical stimulation units 21 are arranged alternately along the axial direction, which not only keeps the position of each electrical stimulation unit 21 stable, but also the reaction force toward the spinal cord 104 exerted on the anchoring units 31 due to expansion improves the fitting effect between the flexible electrodes 211 and the dura mater 103.

[0048] In some preferred structures, the elastic base 212 of the electrical stimulation unit 21 or the end surface of the distal end of the catheter 40 is configured as follows: like Figure 5 As shown, the two axial sides of the side wall 2121 of the elastic base 212 are configured to be relatively inclined, that is, the side wall 2121 is configured to be roughly trapezoidal in shape. In this way, when the distal end of the catheter 40 is pushed toward the distal end of the carrier 10, the distal end of the catheter 40 will force the side wall 2121 to gradually bend from the middle area to the circumferential outside to cover the cylindrical surface of the carrier 10, which is conducive to the elastic base 212 strictly and tightly covering the carrier 10 along the circumferential direction.

[0049] Alternatively, an inclined end surface (not shown) is machined at the end of the catheter 40. When the distal end of the catheter 40 is pushed toward the distal end of the carrier 10, the inclined end surface of the catheter 40 will also force the side wall 2121 to gradually and completely cover the cylindrical surface of the carrier 10 from the middle area to the circumferential outside.

[0050] In some preferred structures, the catheter 40 is also configured with the following structure: like Figure 3 As shown, a notch 41 is arranged at a circumferential position corresponding to the front circumferential position of the catheter 40 and the carrier 10, that is, at the front circumferential direction of the catheter 40, and the notch 41 extends axially and passes through both ends of the catheter 40. The notch 41 allows: when the carrier 10 is in a state of being covered by the catheter 40, the area corresponding to the flexible electrode 211 and the notch 41 is in an exposed state. The catheter 40 configured with the notch 41 has the following advantages in implementing electrical stimulation: after the carrier 10 in a state of being covered by the catheter 40 is sent into the spinal canal cavity 102, the area exposed by the flexible electrode 211 can be used to implement electrical stimulation test on the dura mater 103, and the most effective position for electrical stimulation can be found through continuous testing, and then the catheter 40 is withdrawn from the carrier 10 so that the flexible electrode 211 implements electrical stimulation in a fully expanded manner. Therefore, the notch 41 allows the flexible electrode 211 on the carrier 10 in a covered state to implement electrical stimulation test on the dura mater 103, so that the position of the carrier 10 can be adjusted conveniently during the test. The reduced thickness portion 43 is formed in the conduit 40 on both sides of the notch 41 , that is, the thickness of the conduit 40 on both sides of the notch 41 is reduced, thereby increasing the contact area between the exposed region of the flexible electrode 211 and the hard film 103 .

[0051] In some preferred structures, the carrier 10 and the conduit 40 are further configured as follows: The cross section of the carrier 10 is configured to be an ellipse (not shown), that is, the outer peripheral surface of the carrier 10 is configured to be an elliptical cylinder; the electrical stimulation unit 21 and the anchoring unit 31 are respectively located on both sides of the end axis of the elliptical cylinder, and accordingly, the cross section of the catheter 40 is also configured to be an ellipse matching the carrier 10. The advantage of such a configuration is that the carrier 10 and the catheter 40 are restricted from twisting during the process of being delivered into the spinal canal 102, so that the electrical stimulation unit 21 is always strictly oriented toward the spinal cord 104. In a more preferred structure, an axially extending developing strip (not shown) is arranged at the same circumferential position of the outer peripheral surface of the catheter 40, for example, a developing strip is arranged at a posterior circumferential position, and the developing strip is developed under an imaging device (e.g., an X-ray machine), so as to monitor whether the carrier 10 is twisted during the delivery of the carrier 10 and after the carrier 10 is delivered to the spinal canal 102, so as to ensure that after the catheter 40 exits the carrier 10, the electrical stimulation unit 21 is reset toward the spinal cord 104, and the anchoring unit 31 is reset toward the posterior wall of the spinal canal 102.

[0052] In some preferred structures, the carrier 10 and the conduit 40 are further configured as follows: A plurality of skeletons 42 arranged at intervals along the axial direction are embedded in the tube wall of the catheter 40; a guide bar 44 extending along the axial direction is configured at the circumferential position of the inner wall of the catheter 40 opposite to the notch 41, and a guide groove 12 extending along the axial direction is configured on the carrier 10 on the opposite side of the electrical stimulation unit 21. The advantage of such a configuration is that the guide bar 44 cooperates with the guide groove 12 to limit the torsion of the catheter 40 relative to the carrier 10, so that the flexible electrode 211 is always exposed in the front circumferential position toward the spinal cord 104. In addition, the skeleton 42 is embedded in the catheter 40 to improve the rigidity of the catheter 40 against radial deformation and avoid increasing the bending rigidity of the catheter 40, thereby avoiding the catheter 40 from having a poor ability to resist radial deformation due to the notch 41, so that the catheter 40 still has a better covering effect on the carrier 10 when the notch 41 is configured. Preferably, in the structure in which the skeleton 42 is embedded, the catheter 40 is preferably made of silicone rubber.

[0053] The present invention also provides a method for manufacturing the carrier 10 and a method for assembling the electrical stimulation unit 21 and the carrier 10: The carrier 10 is formed by bending a strip, so that the carrier 10 has a central hole, and the two sides of the strip define a slot 11 after the carrier 10 is bent. Before the strip is bent, the wire 50 is arranged along a side surface of the strip, and the side surface becomes the hole wall of the central hole after the strip is bent, so that the wire 50 is routed in the central hole. Before the strip is bent, the wire 50 contacts at the ends of the wire 50 are arranged on the end walls of the two sides of the strip, so that after the strip is bent into the carrier 10, the wire 50 contacts are located at the two groove walls of the slot 11; the middle area of ​​the elastic base 212 is configured with a convex strip 2122, and the wall of the convex strip 2122 is configured with an electrode contact electrically connected to the flexible electrode 211, so that the boss is inserted into the slot 11, so that the electrode contact is electrically connected to the wire 50 contact. Each wire 50 extends along the axial direction of the carrier 10 and forms circumferentially arranged external contacts at the proximal end of the carrier 10. The cables of the pulse generator 60 are electrically connected to these external contacts through connectors. The above-mentioned molding method of the carrier 10, the attachment method of the electrical stimulation unit 21 to the carrier 10, and the wiring method are ingenious, which reduces the exposure of the wires 50. The above embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention. The protection scope of the present invention is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present invention.

Claims

1. An epidural electrical stimulation device, characterized in that: include: A carrier configured in a rod shape, the carrier having a distal end for entering the spinal canal of the spine through the space between vertebrae and a proximal end retained outside the body; A stimulation array, comprising a plurality of electrical stimulation units, which are arranged on the carrier in sequence along the axial direction from the distal end of the carrier; each of the electrical stimulation units comprises a sheet-shaped elastic substrate attached to the carrier and a sheet-shaped flexible electrode attached to the outer surface of the elastic substrate; A pulse generator, which provides a pulse current for implementing electrical stimulation to the flexible electrode of each electrical stimulation unit through a wire; A catheter is sleeved outside the carrier and can move axially relative to the carrier, and the catheter has a distal end and a proximal end consistent with the carrier; wherein: The elastic base has a folded state in which it is wrapped around the outer peripheral surface of the carrier by elastic deformation, and an expanded state in which it is reversely bent by elastic restoration; The elastic base is forced to switch to a retracted state by moving the distal end of the catheter toward the distal end of the carrier, and the elastic base is released by moving the distal end of the catheter in a direction away from the distal end of the carrier. The elastic base is reversely bent by elastic resetting to switch to an expanded state, so that after the carrier enters the spinal canal, the elastic base switches to the expanded state so that the flexible electrode contacts the dura mater of the spinal cord.

2. The epidural electrical stimulation device according to claim 1, characterized in that: The elastic base has a middle area and side walls symmetrically arranged on both sides of the middle area in a circumferential direction, and the elastic base is attached to the carrier in the middle area; the two side walls are elastically deformed to switch the elastic base to a retracted state, and the side walls are elastically reset to switch the elastic base to an expanded state; The two side edges of the side wall in the circumferential direction are configured to be relatively inclined or the distal end of the conduit is configured to have an inclined end surface.

3. The epidural electrical stimulation device according to claim 1, characterized in that: The epidural electrical stimulation device further comprises an anchor array, the anchor array comprising a plurality of anchor units, the plurality of anchor units being arranged on the carrier at intervals along the axial direction, the anchor units being arranged at circumferential positions opposite to the electrical stimulation units; The anchoring unit has a collapsed state formed by elastic deformation and an expanded state formed by elastic resetting to radially protrude; The anchoring unit is forced to switch to a retracted state by moving the distal end of the catheter toward the distal end of the carrier, and the anchoring unit is released and switched to an expanded state by moving the distal end of the catheter away from the distal end of the carrier. Thus, after the carrier enters the spinal canal, the anchoring unit is switched to an expanded state and abuts against the posterior wall of the spinal canal.

4. The epidural electrical stimulation device according to claim 3, characterized in that: Each of the anchoring units includes a support unit formed by two elastic wires bent into a trapezoidal shape, and the two support units are symmetrically arranged. The support unit is wrapped around the carrier by bending toward the carrier, so that the anchoring unit switches to a retracted state. The support unit is bent in the opposite direction by elastic resetting to abut against the posterior wall of the spinal canal, so that the anchoring unit switches to an expanded state. After switching to the expanded state, the two support units are separated from each other at an angle.

5. The epidural electrical stimulation device according to claim 2, characterized in that: A notch extending axially is configured at a circumferential position corresponding to the middle area of ​​the catheter and the elastic base, and the catheter on both sides of the notch forms a thickness reduction portion. The notch exposes the flexible electrode so that the flexible electrode can contact the dura mater when the catheter is not separated from the carrier.

6. The epidural electrical stimulation device according to claim 1, characterized in that: The carrier is formed by bending the strips, so that the carrier has a central channel, and the two sides of the strips define a slot after the carrier is bent; Before the slat is bent, the wire is arranged along one side surface of the slat, and the wire contacts at the ends of the wire are arranged on the end walls of the two sides of the slat, so that after the slat is bent into a carrier, the wire contacts are located on the two slot walls of the slot; The middle area of ​​the elastic base is provided with a convex strip, the wall of the convex strip is provided with an electrode contact electrically connected to the flexible electrode, and the convex strip is inserted into the slot and bonded, so that the electrode contact is electrically connected to the wire contact.

7. The epidural electrical stimulation device according to claim 5, characterized in that: A plurality of skeletons arranged axially at intervals are embedded in the tube wall of the catheter; a guide strip extending axially is arranged at a circumferential position of the inner wall of the catheter opposite to the notch, and a guide groove extending axially is arranged on the carrier on the opposite side of the electrical stimulation unit, and the guide strip cooperates with the guide groove to limit the twisting of the catheter in the circumferential direction relative to the carrier.

8. The epidural electrical stimulation device according to claim 1, characterized in that: A developing strip extending in the axial direction is arranged on the outer peripheral surface of the guide tube.

9. The epidural electrical stimulation device according to claim 3, characterized in that: The outer peripheral surface of the carrier is configured as an elliptical cylinder; the electrical stimulation unit and the anchoring unit are respectively located on both sides of the end axis of the elliptical cylinder.

10. The epidural electrical stimulation device according to claim 4, characterized in that: The two ends of the elastic wire are fixed to the carrier in a plug-in and bonding manner.

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