Epidural electrical stimulation device

Abstract

The present invention discloses an epidural electrical stimulation device, comprising: a carrier configured in a rod shape, the carrier having a distal end and a proximal end; a stimulation array including a plurality of electrical stimulation units, the plurality of electrical stimulation units being arranged axially in sequence on the carrier; each of the electrical stimulation units including 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 for providing a pulsed current to the flexible electrode; a catheter sleeved outside the carrier, the catheter having a distal end and a proximal end consistent with the carrier; the elastic substrate having a retracted state in which it is elastically deformed to wrap around the outer peripheral surface of the carrier and an unfolded state formed by elastically resetting and bending in the opposite direction, and the catheter axially moving relative to the carrier to switch the elastic substrate to the retracted state or the unfolded state.

Description

Technical Field

[0001] The present invention relates to the technical field of spinal cord electrical stimulation, and particularly to a device for performing electrical stimulation on the spinal cord epidurally. Background Art

[0002] Performing electrical stimulation on the spinal cord epidurally for treating symptoms such as chronic pain and limb paralysis related to spinal cord injury has been proven effective. A typical electrical stimulation method is to insert an electrode through the gap between vertebrae into the spinal canal cavity of the spine, so that the electrode contacts the dura mater of the spinal cord to perform electrical stimulation.

[0003] An electrical stimulation device for performing electrical stimulation on the spinal cord epidurally generally includes: a carrier extending at least axially, a stimulation array attached to the carrier and having a plurality of electrodes arranged axially, and a pulse generator for supplying a pulsed current to the electrodes so that the electrodes can perform electrical stimulation on the spinal cord.

[0004] The contact area between the electrode and the dura mater of the spinal cord is a key factor affecting the therapeutic effect of electrical stimulation. In a typical electrical stimulation device, the carrier is configured as 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 enveloped in a cylindrical shape, therefore, the electrode contacts the dura mater only through an 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 as a paddle shape (or strip shape), thus, this structure of the carrier has a flat surface, and the electrodes in the stimulation array are attached to the surface of the carrier. The electrode contacts the dura mater through a plane and an arc surface. Therefore, the contact area between the electrode on the paddle-shaped carrier and the dura mater is increased compared with that of the electrode on the rod-shaped carrier, but the increase amplitude of the contact area is not large. However, the paddle-shaped carrier is more restricted in movement in the spinal canal cavity than the rod-shaped carrier. For example, the rod-shaped carrier is easier to be dragged along the spinal canal cavity, and it is not easy to damage the dura mater, spinal cord and peripheral tissues when being dragged, while the paddle-shaped carrier is not easy to be dragged along the spinal canal cavity, and the risk of damaging related tissues when being dragged increases.

[0005] After the stimulation array is placed at an appropriate position in the spinal canal lumen, the stability of the position of the carrier is also a key factor affecting the long-term therapeutic effect of electrical stimulation. If the carrier cannot be positioned, the stimulation array may shift with the carrier, resulting in a deterioration or even failure of the electrical stimulation effect. To achieve the positioning of the carrier, in the prior art, a plurality of anchoring components are arranged axially on the carrier (for example, the Chinese patent with the patent number 201910339477.5 provides a carrier with anchoring components). The anchoring component is in close contact with the surrounding relevant tissues through expansion, so as to achieve the positioning of the carrier. However, a significant defect of the anchoring component provided in the prior art is that the anchoring component not only is in close contact with the spinal canal wall, but also is 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 adhere to the epidural space due to the supporting effect of the anchoring component on the carrier. Summary of the Invention

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

[0007] To solve the above technical problems, the technical solution adopted in the embodiment of the present invention is:

[0008] An epidural electrical stimulation device, comprising:

[0009] A carrier configured in a rod shape, the carrier having a distal end for entering the spinal canal lumen of the spine through the space between vertebrae and a proximal end remaining outside the body;

[0010] A stimulation array including a plurality of electrical stimulation units, the plurality of electrical stimulation units being arranged axially on the carrier in sequence from the distal end of the carrier; each of the electrical stimulation units includes a sheet-shaped elastic substrate attached to the carrier and a sheet-shaped flexible electrode attached to the outer surface of the elastic substrate;

[0011] A pulse generator that provides a pulsed current for implementing electrical stimulation to the flexible electrode of each electrical stimulation unit through a wire;

[0012] A catheter sleeved outside the carrier and capable of axially moving relative to the carrier, the catheter having a distal end and a proximal end consistent with the carrier; wherein:

[0013] The elastic substrate has a retracted state in which it is elastically deformed to wrap around the outer peripheral surface of the carrier and an expanded state formed by elastically resetting and bending in the opposite direction;

[0014] The elastic substrate is forced to switch to the retracted state by moving the distal end of the catheter towards the distal end of the carrier, and the elastic substrate is released by moving the distal end of the catheter in a direction away from the distal end of the carrier. The elastic substrate bends reversely by elastic reset to switch to the deployed state. Thus, after the carrier enters the spinal canal lumen, the elastic substrate makes the flexible electrode contact the dura mater of the spinal cord by switching to the deployed state.

[0015] Preferably,

[0016] The elastic substrate has a central region and side walls symmetrically arranged on both sides in the circumferential direction of the central region. The elastic substrate is attached to the carrier in the central region; the two side walls make the elastic substrate switch to the retracted state by elastic deformation, and the side walls make the elastic substrate switch to the deployed state by elastic reset;

[0017] Two side edges in the circumferential direction of the side wall are configured to be relatively inclined or the distal end of the catheter is configured with an inclined end face.

[0018] Preferably, the epidural electrical stimulation device further includes an anchoring array. The anchoring array includes a plurality of anchoring units which are arranged at intervals along the axial direction on the carrier, and the anchoring units are arranged at circumferential positions opposite to the electrical stimulation units;

[0019] The anchoring unit has a retracted state formed by elastic deformation and an expanded state formed by elastic reset with a radial protrusion;

[0020] The anchoring unit is forced to switch to the retracted state by moving the distal end of the catheter towards the distal end of the carrier, and the anchoring unit is released to switch to the expanded state by moving the distal end of the catheter in a direction away from the distal end of the carrier. Thus, after the carrier enters the spinal canal lumen, the anchoring unit abuts against the posterior wall of the spinal canal lumen by switching to the expanded state.

[0021] Preferably, each anchoring unit includes a support unit formed by bending two elastic wires into a trapezoidal shape. The two support units are symmetrically arranged. The support unit wraps around the outside of the carrier by bending towards the carrier, so that the anchoring unit switches to the retracted state. The support unit bends reversely by elastic reset to abut against the posterior wall of the spinal canal lumen, so that the anchoring unit switches to the expanded state. After switching to the expanded state, the two support units are separated at an angle from each other.

[0022] Preferably, a notch extending axially is arranged at a circumferential position corresponding to the middle region of the elastic substrate on the catheter, and the catheter on both sides of the notch forms a thickness weakening portion, and the notch exposes the flexible electrode so that when the catheter is not separated from the carrier, the flexible electrode can contact the dura mater.

[0023] Preferably,

[0024] The carrier is formed by bending a slat, so that the carrier has a central channel, and two side edges of the slat define a slot after the carrier is bent;

[0025] Before the slat is bent, the wire is arranged along one surface of the slat, and the wire contacts at the ends of the wire are arranged on the end walls of the two side edges of the slat, so that after the slat is bent into the carrier, the wire contacts are located on the two groove walls of the slot;

[0026] A rib is arranged in the middle region of the elastic substrate, and electrode contacts electrically connected to the flexible electrode are arranged on the wall of the rib. The rib is inserted into the slot and bonded, so that the electrode contacts are electrically connected to the wire contacts.

[0027] Preferably, a plurality of skeletons arranged at intervals along the axis are embedded in the tube wall of the catheter; a guiding strip extending axially is arranged at a circumferential position of the inner wall of the catheter opposite to the notch, and a guiding groove extending axially is arranged on the carrier on the opposite side of the electrical stimulation unit. The guiding strip cooperates with the guiding groove to limit the catheter from twisting circumferentially relative to the carrier.

[0028] Preferably, a developing strip extending axially is arranged on the outer peripheral surface of the catheter.

[0029] Preferably, the outer peripheral surface of the carrier is configured as an ellipsoidal cylinder surface; the electrical stimulation unit and the anchoring unit are respectively located on both sides of the end axis of the ellipsoidal cylinder surface.

[0030] Preferably, both ends of the elastic wire are fixed to the carrier in a plugging and bonding manner.

[0031] Compared with the prior art, the beneficial effects of the epidural electrical stimulation device provided by the embodiments of the present invention are:

[0032] The catheter, the stimulation array, the anchoring unit, and the carrier cooperate with each other so that the carrier enters the spinal canal cavity in a state with a smaller outer diameter. After the catheter is withdrawn from the carrier, each electrical stimulation unit of the stimulation array switches to the deployed state and reversely wraps 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 compared to the electrodes on the carriers in the prior art. The anchoring unit switches to the expanded state to achieve the positioning of the carrier, so that the positions of the electrical stimulation units on the carrier are kept stable, which is beneficial for the flexible electrodes to perform long-term electrical stimulation on the spinal cord. Description of the Drawings

[0033] In the drawings, which are not necessarily drawn to scale, the same reference numerals may describe similar components in different views. The same reference numerals with alphabetical suffixes or different alphabetical suffixes may represent different instances of similar components. The drawings generally illustrate various embodiments by way of example and not limitation, and are used together with the description and the claims to explain the embodiments of the invention. Where 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 an exhaustive or exclusive embodiment of the device or method.

[0034] Figure 1 View of the state where the carrier in the electrical stimulation device provided by the present invention is covered by the catheter.

[0035] Figure 2 is Figure 1 Enlarged view of local A of

[0036] Figure 3 Cross-sectional view of the state where the carrier in the electrical stimulation device provided by the present invention is covered by the catheter.

[0037] Figure 4 View of the state where the carrier in the electrical stimulation device provided by the present invention is released by the catheter.

[0038] Figure 5 is Figure 4 Enlarged view of local B of

[0039] Figure 6 Schematic structural view of the catheter in the electrical stimulation device provided by the present invention.

[0040] Figure 7 View of the state where the carrier of the electrical stimulation device provided by the present invention enters the spinal canal cavity of the human body.

[0041] Figure 8 is Figure 7 Enlarged view of local C of (the catheter makes the electrical stimulation unit and the anchoring unit in the retracted state).

[0042] Figure 9 is Figure 7 an enlarged view of the local C (after the catheter releases the electrical stimulation unit and the anchoring unit).

[0043] In the figure:

[0044] 10 - carrier; 11 - slot; 12 - guiding groove; 20 - stimulation array; 21 - electrical stimulation unit; 211 - flexible electrode; 212 - elastic substrate; 2121 - side wall; 2122 - rib; 30 - anchoring array; 31 - anchoring unit; 311 - elastic wire; 40 - catheter; 41 - notch; 42 - framework; 43 - thickness reduction part; 44 - guiding bar; 50 - wire; 60 - pulse generator; 101 - vertebra; 102 - spinal canal cavity; 103 - dura mater; 104 - spinal cord. Specific embodiments

[0045] In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0046] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the art to which the present invention pertains. The "first", "second", and similar terms used in the present invention do not denote any order, quantity, or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or items appearing before this word cover the elements or items listed after this word and their equivalents, without excluding other elements or items. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left", "right", etc. are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0047] In order to keep the following description of the embodiments of the present invention clear and concise, the detailed descriptions of known functions and known components are omitted in the present invention.

[0048] Embodiments of the present invention disclose an epidural electrical stimulation device, such as Figure 1As shown, the epidural electrical stimulation device is used to perform electrical stimulation on the spinal cord 104 in the spinal canal cavity 102 of the spine. Specifically, the electrodes in the device perform electrical stimulation on the spinal cord 104 outside the dura mater 103 of 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 diagnosis and treatment site, but also perform long-term electrical stimulation (or permanent electrical stimulation) on the spinal cord 104. For example, enable the patient to carry the device for a long time and obtain long-term electrical stimulation treatment in a non-diagnosis and treatment site.

[0049] As Figure 7 and 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.

[0050] The carrier 10 is used to deliver the stimulation array 20 from outside the body to the spinal canal cavity 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 oval shape. The carrier 10 has dimensions that are much larger in the axial direction than in the radial direction. The carrier 10 has a proximal end on the operator's side and a distal end on the side away from the operator in the axial direction. During the process of delivering the stimulation array 20 to the spinal canal cavity 102, the distal end of the carrier 10 first enters the spinal canal cavity 102 through the gap between the rear sides of the vertebrae 101. Subsequently, by axially pushing the carrier 10, as Figure 7 shown, the axial section of the carrier 10 attached with the stimulation array 20 enters the spinal canal cavity 102, and the proximal end of the carrier 10 is located outside the body for attaching the cable of the pulse generator 60.

[0051] The carrier 10 is configured to have a certain stiffness so that the carrier 10 always remains in a straight or nearly straight state. And the carrier 10 is configured as an insulator to avoid weakening of the pulsed current applied by the stimulation array 20 and to avoid the pulsed current being applied to tissues other than the spinal cord 104. A polymer material can be selected to make the carrier 10, so as to meet the requirements for the stiffness and insulation of the carrier 10. A polymer with better mechanical properties and biocompatibility such as polyurethane is selected to make the carrier 10.

[0052] As Figure 1As 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.

[0053] 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 2 As 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.

[0054] The elastic substrate 212 can be made of a polymer material. For example, it can be made of the same polymer material as the carrier 10, specifically, a polymer such as polyurethane. The elastic substrate 212 can be made by the following process: Select a polyurethane sheet, then cut the polyurethane sheet, and then bend the sheet under heating conditions so that the elastic substrate 212 is in a reverse bending state opposite to the retracted state under natural conditions (i.e., without external force).

[0055] Such as Figure 1 and Figure 2 and also Figure 4 and Figure 5 As shown, the anchoring array 30 includes a plurality of anchoring units 31. The plurality of anchoring units 31 are arranged in sequence along the axial direction from the distal end of the carrier 10 and attached to the carrier 10. And all the anchoring units 31 are located at the rear circumferential position of the carrier 10. Thus, as Figure 8 shown, after the carrier 10 is inserted into the spinal canal lumen 102 with the stimulation array 20 facing the spinal cord 104, all the anchoring units 31 face the rear wall of the spinal canal lumen 102. At this time, the stimulation array 20 and the anchoring array 30 are respectively located on the front and rear sides of the carrier 10.

[0056] Each anchoring unit 31 is configured with the following deformation characteristics: As Figure 2 shown, in the natural state, the anchoring unit 31 is in a state of radially protruding backward. This state may be referred to as the expanded state of the anchoring unit 31. As Figure 5 shown, under the retracting action (i.e., making the anchoring unit 31 retract 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.

[0057] In some preferred structures, the anchoring unit 31 is configured as follows:

[0058] 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 the expanded state, the two support units protrude radially backward, and there is a certain angle between the two support units. Under the retracting action, the two support units bend in the opposite direction and wrap around the outer peripheral surface of the carrier 10. Thus, after the carrier 10 is inserted into the spinal canal lumen 102 with the stimulation array 20 facing the spinal cord 104 and the anchoring component is switched to the expanded state by releasing the anchoring component, as Figure 9 shown, the two support units of each anchoring unit 31 support the relevant tissues on the rear wall of the spinal canal lumen 102 (such as vertebral body 101 tissue, muscle tissue at the intervertebral space of the vertebral body 101) in an angled manner.

[0059] 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.

[0060] 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.

[0061] 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 covered by the catheter 40 .

[0062] 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.

[0063] The catheter 40, the stimulation array 20, the anchoring unit 31, and the carrier 10 cooperate with each other such that the carrier 10 enters the spinal canal lumen 102 in a state with a smaller outer diameter. After the catheter 40 is withdrawn from the carrier 10, each electrical stimulation unit 21 of the stimulation array 20 switches to the deployed state and is reversely wrapped around the spinal cord 104. Thus, the flexible electrode 211 on the carrier 10 in the present invention obtains a larger contact area with the dura mater 103 compared to the electrodes on the carrier 10 in the prior art. The anchoring unit 31 switches to the expanded state to position the carrier 10, so that the position of the electrical stimulation unit 21 on the carrier 10 remains stable, which is beneficial for the flexible electrode 211 to perform long-term electrical stimulation on the spinal cord 104.

[0064] In some preferred structures, such as Figure 9 shown, the anchoring unit 31 and the electrical stimulation unit 21 are arranged alternately along the axial direction. This can not only keep the position of each electrical stimulation unit 21 stable, but also the reaction force in the direction towards the spinal cord 104 that the anchoring unit 31 receives due to expansion will improve the fitting effect between the flexible electrode 211 and the dura mater 103.

[0065] In some preferred structures, the elastic substrate 212 of the electrical stimulation unit 21 or the end face of the distal end of the catheter 40 is configured as follows:

[0066] Such as Figure 5 shown, the two side edges of the side wall 2121 of the elastic substrate 212 in the axial direction are configured to be relatively inclined, that is, the side wall 2121 is configured to have a generally trapezoidal outer shape. In this way, when the distal end of the catheter 40 advances towards 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 region to the circumferential outside to wrap the cylindrical surface of the carrier 10, which is beneficial for the elastic substrate 212 to tightly wrap the carrier 10 strictly along the circumference.

[0067] Alternatively, an inclined end face (not shown) is machined at the end of the catheter 40. When the distal end of the catheter 40 advances towards the distal end of the carrier 10, the inclined end face of the catheter 40 will also force the side wall 2121 to gradually wrap the cylindrical surface of the carrier 10 completely from the middle region to the circumferential outside.

[0068] In some preferred structures, the catheter 40 is further configured as follows:

[0069] Such as Figure 3As shown, at the circumferential position corresponding to the front circumferential position of the catheter 40 and the carrier 10, that is, at the front circumferential arrangement of the catheter 40, a notch 41 is configured. The notch 41 extends axially and penetrates both ends of the catheter 40. The notch 41 enables: when the carrier 10 is in a state of being covered by the catheter 40, the area corresponding to the notch 41 of the flexible electrode 211 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 lumen 102, the exposed area of the flexible electrode 211 can be used to perform an electrical stimulation test on the dura mater 103. By continuously testing, the most effective position for electrical stimulation can be found, and then the catheter 40 is withdrawn from the carrier 10 so that the flexible electrode 211 is implemented in a fully deployed manner for electrical stimulation. Therefore, the notch 41 allows the flexible electrode 211 on the carrier 10 in the covered state to perform an electrical stimulation test on the dura mater 103, thereby facilitating the adjustment of the position of the carrier 10 during the test process. By forming a thickness reduction portion 43 on the catheter 40 on both sides of the notch 41, that is, by making the catheter 40 on both sides of the notch 41 thinner in thickness, the contact area between the exposed area of the flexible electrode 211 and the dura mater 103 is increased.

[0070] In some preferred structures, the carrier 10 and the catheter 40 are further configured as follows:

[0071] The cross-section of the carrier 10 is configured as an ellipse (not shown), that is, the outer peripheral surface of the carrier 10 is configured as an elliptical cylindrical surface; the electrical stimulation unit 21 and the anchoring unit 31 are respectively located on both sides of the end axis of the elliptical cylindrical surface. Correspondingly, the cross-section of the catheter 40 is also configured as an ellipse matching the carrier 10. The advantage of such a configuration is: to limit the torsion of the carrier 10 and the catheter 40 during the process of being sent into the spinal canal lumen 102, so that the electrical stimulation unit 21 is always more strictly oriented towards the spinal cord 104. In a more preferred structure, an axially extending imaging strip (not shown) is arranged at the same circumferential position on the outer peripheral surface of the catheter 40, for example, an imaging strip is arranged at the rear circumferential position. The imaging strip is imaged under an imaging device (such as an X-ray machine), so as to monitor whether the carrier 10 has twisted during the process of delivering the carrier 10 and after the carrier 10 is delivered into the spinal canal lumen 102, so as to ensure that after the catheter 40 is withdrawn from the carrier 10, the electrical stimulation unit 21 is reset towards the spinal cord 104, and the anchoring unit 31 is reset towards the rear wall of the spinal canal lumen 102.

[0072] In some preferred structures, the carrier 10 and the catheter 40 are further configured as follows:

[0073] A plurality of skeletons 42 are embedded in the tube wall of the catheter 40 and arranged at intervals along the axial direction; a guiding strip 44 extending along the axial direction is arranged at the circumferential position of the inner wall of the catheter 40 opposite to the notch 41, and a guiding groove 12 extending along the axial direction is arranged on the carrier 10 on the opposite side of the electrical stimulation unit 21. The advantage of such an arrangement is that the guiding strip 44 cooperates with the guiding groove 12 to limit the torsion of the catheter 40 relative to the carrier 10, so that the flexible electrode 211 is always exposed at the front circumferential position facing the spinal cord 104. In addition, the skeleton 42 is embedded in the catheter 40 to improve the stiffness of the catheter 40 against radial deformation without increasing the bending stiffness of the catheter 40, thereby avoiding the deterioration of the ability of the catheter 40 to resist radial deformation due to the arrangement of the notch 41, so that the catheter 40 still has a better covering effect on the carrier 10 when the notch 41 is provided. Preferably, in the structure where the skeleton 42 is embedded, the catheter 40 is preferably made of silicone rubber.

[0074] The present invention also provides a method for manufacturing the carrier 10 and an assembly method for the electrical stimulation unit 21 and the carrier 10:

[0075] The carrier 10 is formed by bending a strip, so that the carrier 10 has a central channel, and two side edges of the strip define a slot 11 after the carrier 10 is bent. Before the strip is bent, the wire 50 is arranged along one side surface of the strip, and this side surface becomes the wall of the central channel after the strip is bent, so that the wire 50 runs in the central channel. Before the strip is bent, the wire 50 contacts at the end of the wire 50 are arranged on the end walls of the two side edges of the strip, so that after the strip is bent into the carrier 10, the wire 50 contacts are located on the two slot walls of the slot 11; a convex strip 2122 is arranged in the middle area of the elastic base 212, and electrode contacts electrically connected to the flexible electrode 211 are arranged on the wall of the convex strip 2122, so that the boss is inserted into the slot 11, so that the electrode contacts are electrically connected to the wire 50 contacts. 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, and the cable of the pulse generator 60 is electrically connected to these external contacts through a connector. The above-mentioned forming method of the carrier 10, the attaching method of the electrical stimulation unit 21 and the carrier 10, and the wiring method are ingenious, reducing the exposure of the wire 50.

[0076] The above embodiments are only exemplary embodiments of the present invention and are not used to limit the present invention. The protection scope of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent replacements within the essence and protection scope of the present invention, and such modifications or equivalent replacements should also be regarded as falling within the protection scope of the present invention.

Claims

1. An epidural electrical stimulation device, characterized in that, Comprising: A carrier configured to be rod-shaped, the carrier having a distal end for entering the spinal canal cavity of the spine through the space between vertebrae and a proximal end retained outside the body; A stimulation array including a plurality of electrical stimulation units, the plurality of electrical stimulation units being axially arranged on the carrier in sequence from the distal end of the carrier; each of the electrical stimulation units includes 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 that provides a pulsed current for implementing electrical stimulation to the flexible electrode of each electrical stimulation unit through a wire; A catheter sleeved outside the carrier and capable of axially moving relative to the carrier, the catheter having a distal end and a proximal end consistent with the carrier; wherein: The elastic substrate has a retracted state in which it elastically deforms to wrap around the outer peripheral surface of the carrier and an unfolded state formed by elastic reset and reverse bending; By moving the distal end of the catheter towards the distal end of the carrier, the elastic substrate is forced to switch to the retracted state, and by moving the distal end of the catheter in a direction away from the distal end of the carrier, the elastic substrate is released, and the elastic substrate reversely bends through elastic reset to switch to the unfolded state. Thus, after the carrier enters the spinal canal cavity, the elastic substrate switches to the unfolded state to bring the flexible electrode into contact with the dura mater of the spinal cord; The elastic substrate has a central region and side walls symmetrically arranged on both sides in the circumferential direction of the central region, and the elastic substrate is attached to the carrier in the central region; the two side walls elastically deform to switch the elastic substrate to the retracted state, and the side walls elastically reset to switch the elastic substrate to the unfolded state; two side edges in the circumferential direction of the side walls are configured to be relatively inclined or the distal end of the catheter is configured with an inclined end face; After the elastic substrate switches from the retracted state to the unfolded state, the side walls reversely bend through elastic reset to wrap around the outside of the spinal cord dura mater.

2. The epidural electrical stimulation device according to claim 1, wherein, The epidural electrical stimulation device further includes an anchoring array, the anchoring array including a plurality of anchoring units, the plurality of anchoring units being axially spaced and arranged on the carrier, and the anchoring units being arranged at circumferential positions opposite to the electrical stimulation units; The anchoring unit has a retracted state formed by elastic deformation and an expanded state formed by elastic reset and radial protrusion; By moving the distal end of the catheter towards the distal end of the carrier, the anchoring unit is forced to switch to the retracted state, and by moving the distal end of the catheter in a direction away from the distal end of the carrier, the anchoring unit is released and the anchoring unit switches to the expanded state. Thus, after the carrier enters the spinal canal cavity, the anchoring unit switches to the expanded state and abuts against the posterior wall of the spinal canal cavity.

3. The epidural electrical stimulation device according to claim 2, wherein Each of the anchoring units includes a support unit formed by bending two elastic wires into a trapezoidal shape. The two support units are symmetrically arranged. The support unit wraps around the carrier by bending towards the carrier, so that the anchoring unit switches to the retracted state. The support unit bends reversely by elastic reset to abut against the posterior wall of the spinal canal cavity, so that the anchoring unit switches to the expanded state. After switching to the expanded state, the two support units are angularly separated from each other.

4. The epidural electrical stimulation device according to claim 1, characterized in that, An axially extending notch is configured at the circumferential position corresponding to the middle region of the elastic base of the catheter. The catheter on both sides of the notch forms a thickness weakening portion. The notch exposes the flexible electrode so that when the catheter is not separated from the carrier, the flexible electrode can contact the dura mater.

5. The epidural electrical stimulation device according to claim 1, wherein The carrier is formed by bending a slat, so that the carrier has a central channel. Moreover, the two side edges of the slat define a slot after the carrier is bent. Before the slat is bent, the wire is arranged along one surface of the slat, and the wire contacts at the end of the wire are arranged on the end walls of the two side edges of the slat. Thus, after the slat is bent into the carrier, the wire contacts are located on the two groove walls of the slot. A rib is configured in the middle region of the elastic base. Electrode contacts electrically connected to the flexible electrode are configured on the wall of the rib. The rib is inserted into the slot and bonded, so that the electrode contacts are electrically connected to the wire contacts.

6. The epidural electrical stimulation device according to claim 4, characterized in that, A plurality of skeletons arranged at intervals along the axis are embedded in the tube wall of the catheter. A guiding strip extending along the axis is configured at the circumferential position of the inner wall of the catheter opposite to the notch. A guiding groove extending along the axis is configured on the carrier on the opposite side of the electrical stimulation unit. The guiding strip cooperates with the guiding groove to limit the circumferential torsion of the catheter relative to the carrier.

7. The epidural electrical stimulation device according to claim 1, characterized in that A developing strip extending along the axis is configured on the outer peripheral surface of the catheter.

8. The epidural electrical stimulation device according to claim 2, wherein The outer peripheral surface of the carrier is configured as an elliptical cylindrical surface. The electrical stimulation unit and the anchoring unit are respectively located on both sides of the end axis of the elliptical cylindrical surface.

9. The epidural electrical stimulation device according to claim 3, wherein, Both ends of the elastic wire are fixed to the carrier in a plugging and bonding manner.

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