Integrated radiofrequency device for intraosseous nerve ablation

Abstract

An integrated radiofrequency (RF) ablation device that performs the function of both a stylet and an RF probe. The RF ablation device comprises an elongate shaft or tube having a distal resilient section, a proximal rigid section, and a handle at a proximal end attached to a proximal end of the elongate shaft or tube. The resilient section of the straight rod is configured to bend or flex but remains straight when not constrained or caused to bend by an outside force.

Description

INTEGRATED RADIOFREQUENCY DEVICE FOR INTRAOSSEOUS NERVE ABLATIONFIELD

[0001] Described herein are various implementations of a radiofrequency (RF) ablation apparatus configured to be introduced into a vertebral body for carrying out RF ablation of one or more nerves within the vertebral body, nerves innervating one or more endplates of the vertebral body, and / or nerves innervating an intervertebral disc adjacent the vertebral body and methods of use thereof. The RF ablation apparatus may comprise an integrated RF probe and stylet that is constructed such that it is capable of further penetrating through cancellous bone tissue within the vertebral body.BACKGROUND

[0002] Chronic back pain is a serious affliction that can greatly impact both physical and mental health. Back pain affects millions of people worldwide each year. According to Center for Disease Control and Prevention (CDC), in 2019, 39.0% of adult Americans reported having back pain. Research has reported that low back pain and neck pain tops US health spending. Further, low back pain is a major cause for work-related disability. Back pain may arise from strained muscles, ligaments, or tendons in the back and / or structural problems with bones or spinal discs. Existing treatments for chronic back pain vary widely, including physical therapy and exercise, chiropractic treatments, injections, rest, and pharmacological therapies such as opioids, pain relievers, or anti-inflammatory medications. Patients with severe back pain may get surgical intervention such as vertebral fusion, discectomy (e.g., total disc replacement), or disc repair. Existing treatments can be costly, addictive, temporary, ineffective, and / or can increase the pain or require long recovery times. In addition, existing treatments do not provide adequate relief for the majority of patients and only a small percentage are surgically eligible.SUMMARY

[0003] Applicant's existing technology (the Intracept” procedure by Relievant ) offers a safe and effective minimally invasive procedure that targets intraosseous nerves {e.g., the basivertebral nerve) for the relief of chronic low back pain. As disclosed herein, several embodiments provide additional modalities and methods of relief for patients and adjunct technologies.

[0004] According to the present disclosure, an integrated radiofrequency (RF) ablation device for ablation of one or more nerves (e.g., a basivertebral nerve) residing inside a vertebral body comprises an RF probe having a distal end, an elongate shaft, tube, or rod having a distal resilient section, and a handle at a proximal end attached to a proximal end of the elongate shaft, tube, or rod. The distalend of the RF probe comprises a distal tip electrode. At least a portion of the elongate shaft, tube£or rod comprises conductive material so as to function as a second electrode of a bipolar electrode configuration with the distal tip electrode. An insulation joint is positioned between the distal tip electrode and the distal end of the elongate shaft, tube, or rod so as to electrically isolate the components of the bipolar electrode configuration. Further, the conductive material of the portion of the elongate shaft, tube or rod may be covered by an insulation layer (e.g., dielectric coating or heat-shrink coating). The bipolar electrode is configured to apply radiofrequency energy to generate heat sufficient to cause ablation of the one or more nerves. The handle is capable of receiving mechanical impact (e.g., from a mallet), which is configured to advance the RF probe inside the vertebral body, forming a path, e.g., a generally straight path or a curved path, in the cancellous bone tissue. Thus, the RF probe may be malletable, or capable of being malleted.

[0005] The elongate shaft, tube, or rod of the integrated RF ablation device may further comprise a proximal rigid section disposed between the distal resilient section and the handle. In some embodiments, the elongate shaft, tube or rod is affixed to the handle, so that turning the handle also causes rotation of the elongate shaft, tube or rod. The handle may comprise an electrical connection port located at a handle head surface.

[0006] In some embodiments, the elongate shaft, tube, or rod may comprise a hypotube made of a rigid material, e.g., metal (such as stainless steel, titanium, nickel), metal alloy material such as nickel titanium alloy commonly known as nitinol), hard plastic, ceramic, or other polymeric material. The distal resilient section of the elongate shaft, tube, or rod may have slits formed on the hypotube to facilitate bending or flexing under force and shape-restoring when the force is relieved. In some embodiments, the slits may be formed through a partial thickness of the hypotube, having a length that is significantly larger than a width. In some embodiments, the length direction of the slits is arranged substantially perpendicular to a longitudinal axis of the hypotube. In some implementations, the slits are arranged in a chevron pattern.

[0007] In some embodiments, the distal resilient section of the elongate shaft, tube or rod is made of a flexible and resilient material, and the proximal rigid section is made of a hard and rigid material such that the elongate shaft, tube, or rod does not buckle when the handle is malleted. In some embodiments, the distal resilient section is pre-curved (e.g., via use of shape memory material and heat setting techniques) to have a slight curve in a resting state. In some embodiments, the distal resilient section is not resilient and is instead rigid.

[0008] Inside the elongate shaft, tube, or rod (e.g., hypotube) of the integrated RF ablationdevice, a plurality of electrical wires extend to make an electrical connection between the distal end of the RF probe (e.g., at least one of the bipolar electrode pair) and the connection port at the handle. In some embodiments, the plurality of electrical wires form an integrated braided cable, and the distal end of the braided cables may be welded to the distal tip electrode to form an electrical connection). The electrical wires (e.g., braided cable) may be surrounded by an insulation layer within the hypotube so as to electrically isolate the electrode components of the bipolar electrode pair and to thermally insulate at least a portion of a conductive outer surface of the hypotube.

[0009] In some embodiments, the RF probe of the integrated RF ablation device comprises a bullet-shaped or bull-nose probe head to facilitate the penetration of cancellous bone tissue when a mechanical impact is received by the handle. In some embodiments, the RF probe of the integrated RF ablation device comprises a bevel-tipped or angled head.

[0010] According to the present disclosure, a method of accessing and ablating one or more nerves (e.g., a basivertebral nerve) within a vertebral body comprises: forming a curved path in the vertebral body with a curved cannula assembly, the curved path being directed toward a pre-selected or predefined target treatment region; removing a curved stylet (e.g., J-stylet) of the curved cannula assembly from an internal channel in a curved cannula of the curved cannula assembly; inserting an integrated radiofrequency (RF) ablation device into the internal channel of the curved cannula, and advancing the RF ablation device forward in a straight path beyond the open distal tip of the curved cannula. The method also includes ablating the one or more nerves within the vertebral body using the integrated RF ablation device.

[0011] In some implementations, the method further includes monitoring the curved path formation by intraoperative visualization (e.g., fluoroscopy or other imaging modality) and determining if the curved path is undershooting or overshooting the pre-selected target treatment region based on the operative visualization monitoring. In response to a determination that the curved path is undershooting or overshooting, the method may further include terminating the advancement of the curved cannula of the curved cannula assembly before the curved path reaches the target treatment region.

[0012] The method may include determining if the straight path formed by the integrated RF ablation device reaches the target treatment region by intraoperative visualization (e.g., fluoroscopy or other imaging modality). In response to a determination that the path reaches the target treatment region, the method may include performing RF ablation with the RF ablation device. In some embodiments, the operative visualization is fluoroscopic imaging.

[0013] In some implementations, the integrated RF ablation device comprises an RF probeincluding a distal end configured to function as a bipolar electrode, an elongate shaft, tube, or rod having a resilient section attached to the distal end, and a handle at the proximal end, the handle which is attached to the elongate shaft, tube, or rod. The resilient section may be configured to bend or flex and may be capable of recovering its shape (e.g., via shape memory material). In some implementations, the RF ablation device may have a pre-curved (e.g., via shape memory material and shape setting or heat setting) distal portion (e.g., resilient section) such that a curved path is formed instead of a straight path. Different RF ablation devices may have a different degree of curvature as required and / or desired.

[0014] According to the present disclosure, the integrated RF ablation device may be part of a kit comprising access tools, wherein the access tools may include an introducer cannula assembly and a curved cannula assembly. In some embodiments, the introducer cannula assembly includes an introducer cannula and an introducer stylet, and the curved cannula assembly includes a curved cannula (e.g., a cannula with a pre-curved or curveable distal end portion) and a J-stylet (e.g., a stylet with a pre-curved or curveable distal end portion).

[0015] The devices and methods summarized above and set forth in further detail below describe certain actions taken by a practitioner; however, it should be understood that they can also include the instruction of those actions by another party. Thus, actions such as "ablating" or "advancing" include "instructing the ablating or advancing." Further aspects of embodiments of the disclosure will be discussed in the following portions of the specification. With respect to the drawings, elements from one figure may be combined with elements from the other figures.BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Several embodiments of the disclosure will be more fully understood by reference to the following drawings, which are for illustrative purposes only:

[0017] FIG. 1 illustrates an example set of access tools and a treatment device configured to access and ablate a nerve within a vertebral body.

[0018] FIGS. 2 - 5 are schematic views illustrating steps of an example treatment process for accessing a vertebral body and ablating a nerve within the vertebral body.

[0019] FIG. 6 illustrates an elevation view of an example integrated RF ablation device configured to access and ablate a nerve within a vertebral body.

[0020] FIG. 7 is a cross-sectional view of a distal end of the example integrated RF ablation device shown in FIG. 6.

[0021] FIG. 8 is a detailed view of an example of a resilient section proximal to the distal endof the example integrated RF ablation device shown in FIG. 6.DETAILED DESCRIPTION

[0022] Damaged or degenerated vertebral endplates may be significant sources of chronic low back pain. The pain may be transmitted from the superior and interior endplates through one or more nerves (e.g., a basivertebral nerve, which enters through an opening on the vertebral body and branches near the center of the vertebral body, sending nerves to innervate the superior and inferior endplates). Therefore, this type of back pain may be called vertebrogenic back pain. The Applicant's research and clinical trials have established that such vertebrogenic back pain can be treated by RF ablation. In some implementations, discogenic back pain may also be treated by applying ablative RF energy within the vertebral body.A. Access Tools and Treatment Device

[0023] Procedures have been developed by the Applicant to target one or more nerves within the vertebral body (e.g., the basivertebral nerve) so as to relieve the chronic low back pain and to improve functioning. In some implementations, a radiofrequency (RF) ablation probe is introduced into a selected vertebral body to perform such a non-invasive RF ablation or other modulation procedure. To modulate the whole nerve within the vertebral body, a small area near the center of the vertebral body where the basivertebral nerve branches off is usually pre-identified and targeted. The targeted area may be in a posterior half of the vertebral body.

[0024] FIG. 1 shows an example embodiment of a set of access tools and treatment device 100 for performing a non-invasive procedure to access a target treatment region within a vertebral body and to ablate the one or more nerves (e.g., basivertebral nerve) therein. As shown in FIG. 1, the tool set includes an introducer assembly 110 comprising an introducer cannula 112 and an introducer stylet 120, a curved cannula assembly 130 comprising a curved cannula 132 and a J-stylet 140, a straight stylet 150, and a radiofrequency (RF) energy delivery device 160, such as an RF probe. The access tools and treatment device 100 may be provided as a kit. In some embodiments, the kit of access tools and treatment device 100 may optionally include one or more additional introducer cannulas 112, curved cannulas 132, and / or an additional straight stylet 150 possibly having a different length from the first straight stylet 150. In some embodiments, the kit may include at least two of every access tool and at least two treatment devices. The optional additional access tools may be adapted to access one or more additional vertebrae during a treatment procedure.

[0025] As illustrated in FIG. 1, the introducer cannula 112 comprises a straight hypotube 114with a distal end and an introducer handle 116 that is attached to the straight hypotube 114. The straight hypotube 114 can be made of a hard and stiff material, e.g., metal, hard plastic, ceramic, or composite material. The introducer handle 116 at the proximal end can be made of a plastic material or another type of suitable material that is capable of withstanding impact from a mallet. The introducer stylet 120 comprises a straight rod (not shown) having a pointed tip 122 at the distal end and a first handle 124 at the proximal end attached to the straight rod. The straight rod (not shown) with the pointed tip 122 may be made of a hard and stiff material, e.g., metal, hard plastic or ceramic, and the first handle 124 may be made of a plastic material or a material that is capable of withstanding impact. The pointed tip 122 may be round tipped, bevel tipped or trocar tipped. The introducer handle 116 and the introducer cannula 112 together have an internal channel from end-to-end configured to receive the introducer stylet 120 such that the pointed tip 122 at the distal end of the introducer stylet 120 protrudes an open distal end of the straight hypotube 114 of the introducer cannula 112. As such, during the RF ablation procedure when the introducer cannula assembly is used to form a channel in a vertebral body, the pointed tip 122 penetrates the bone tissue and leading the hypotube 114 to advance. As can be seen in FIG. 1, the pointed tip 122 (and the connected straight rod) of the introducer stylet 120 is slightly smaller than the internal channel of the straight tube 114 of the introducer cannula 112. As such, the introducer stylet 120 can be freely inserted into and removed from introducer cannula 112.

[0026] Regarding the curved cannula assembly 130, the curved cannula 132 comprises a straight tube section 134, a distal curved tube section 133 that is extended from the straight tube section 134, and a proximal end 136. The proximal end 136 comprises an adjustment wheel 138 threaded onto a thread section 137. By turning the adjustment wheel 138, the adjustment wheel 138 moves along the length of the thread section 137 of the proximal end 136 so that a distance between the adjustment wheel 138 and an end surface of the proximal end 136 can be adjusted. The curved distal tube section 133 of the curved cannula 132 comprises an elastic or resilient material that can be bent or straightened and can restore its original pre-curved shape.

[0027] The outside diameter of the distal curved tube section 133 and the elongate straight tube section 134 are made slightly smaller than the diameter of the internal channel of the straight hypotube 114 of the introducer cannula 112. In this way, the curved cannula assembly 130 can be inserted into and removed from the hypotube 114. The diameter matching between the distal curved tube section 133 and the internal channel of the introducer cannula 112 is similar to the diameter matching between the introducer stylet 120 and the introducer cannula 112. As such, the resilient curved distal curved tube section 133 can be straightened and inserted into the internal channel of the introducer cannula 112. Thetotal length of the distal curved tube section 133 and the straight tube section 134 of the curved cannula 132 is configured such that, when fully engaged, the distal curved tube section 133 of the curved cannula 132 can at least partially penetrate through the straight hypotube 114 of the introducer cannula 112 and come out of the open distal end of the hypotube 114. Once out of the open distal end of the straight hypotube 114, the distal curved tube section 133 of the curved cannula 132 will recover its curved shape because it is made of a resilient material (e.g., shape memory material).

[0028] When fully engaged, the adjustment wheel 138 at the proximal end 136 of the curved cannula 132 is in contact with an upper end surface of the introducer handle 116 of the introducer cannula 112. The length of the curved tube section 133 coming out of the straight hypotube 114 of the introducer cannula 112 depends on the location of the adjustment wheel 138 on the thread section 137 of the proximal end 136. When the adjustment wheel 138 is moved to the lowest point of thread section 137, as illustrated in FIG. 1, the length of the distal curved tube section 133 protruding out of the open distal end of the straight hypotube 114 is the shortest. On the other hand, when the adjustment wheel 138 is at the highest point of thread section 137, the length of the distal curved tube section 133 protruding out of the open distal end of the straight hypotube 114 is the longest. During the RF ablation procedure, when a channel is formed in a vertebral body, the distal curved tube section 133 helps penetrate the bone tissue medially, toward the center region of the vertebral body. The length of the medial path may be adjusted by the adjustment wheel 138 and the malleting of the curved cannula assembly.

[0029] In FIG. 1, the J-stylet 140 comprises a rod portion (not shown) with a distal tip 142 and a second handle 144 attached to the rod portion (not shown). The distal portion of the rod portion (not shown) of the J-stylet 140 is curved having the same or similar curvature of the distal curved tube section 133 of the curved cannula 132, and comprises an elastic or resilient material that is capable of bending and restoring its original shape. The curved cannula 132 includes an internal channel running through its length from the proximal end 136 through the tube sections 134 and 133 and to a distal end at the curved tube section 133. The rod portion (not shown) of the J-stylet 140 is slightly smaller than the internal channel formed in the curved cannula 132. As such, the J-stylet 140 is configured to be received in the internal channel in the curved cannula 132 such that the distal tip 142 of the J-stylet 140 slightly protrudes from the open distal end of the curved cannula 132. When the J-stylet 140 is fully engaged with the curved cannula 132, the second handle 144 of the J-stylet 140 is in contact with proximal end 136 of the curved cannula 132, and the distal tip 142 of the J-stylet 140 is slightly outside of the open distal end of the curved tube section 133. The distal tip 142 can comprise a hard and stiff material, e.g., metal, and can be tipped, e.g., round tipped, bevel tipped or trocar tipped, so that it can help the advancement ofthe curved tube section 133 of the curved cannula 132 within a bone. The curved cannula 132 and the J- stylet 140 may each comprise a straight proximal main section and a curved distal section. The location and curvature of the curved distal sections of the curved cannula 132 and the J -sty I et 140 may correspond to each other. The proximal end 136 of the curved cannula 132 and second handle 144 of the J -sty let 140 may each comprise markings or features to indicate the direction of the curved sections so that the curved sections can correspondingly align to each other and the curved tube section 133 of the curved cannula 132 and the distal tip 142 of the J-stylet 140 can be steered together during a procedure.

[0030] In FIG. 1, the straight stylet 150 comprises a straight rod 156 with a distal tip 152 and a third handle 154 attached to the straight rod 156. At least the distal portion of the straight rod 152 comprises an elastic or resilient material that is capable of bending and restoring its original shape. Further, the outer diameter of the straight rod 156 of the straight stylet 150 may be similar to that of the rod portion of the J-stylet 140. As such, the rod 156 can fit into the internal channel of the curved cannula 132 like the J-stylet 140. When fully engaged, the distal tip 152 of the straight stylet 150 penetrates out of the open distal end of the distal curved tube section 133 of the curved cannula 132. When coming out of the open distal end of the curved cannula 132, the distal section of the straight stylet 150 recovers its shape and becomes straight or another pre-formed shape. The curved cannula 132, the J-stylet 140 and the straight stylet 150 are constructed in such a way that the J-stylet 140 and the straight stylet 150 can be inserted into and removed from the curved cannula 132 during an ablation procedure. The construction consideration may include diameter matches between the internal channel of the curved cannula 132 and the rod portions of the J-stylet 140 and the straight stylet 150. The distal tip 152 can comprise a hard and stiff material, e.g., metal, and can be tipped, e.g., round tipped, bullet shaped, bevel tipped or trocar tipped. The J-stylet 140 and the straight stylet 150 may either be entirely or partially made of a radiopaque material or include an embedded radiopaque marker band at the distal tip to facilitate visualization under fluoroscopic or CT imaging.

[0031] The various proximal end features, including the introducer handle 116, the first handle 124, the proximal end 136, second handle 144, and the third handle 154 can be made of similar materials and be attached to their corresponding tube or rod sections similarly. For example, the introducer handle 116 can be made of a material that can withstand impact, e.g., plastic, wood, aluminum alloy, or a composite material, because when assembled the introducer assembly 110 may be configured to receive impact from a mallet in order for the pointed tip 122 and the distal end of the straight hypotube 114 to penetrate and advance into a body part, e.g., a pedicle of a vertebra. If the introducer handle 116 is made of plastic, it can be insert molded with the straight hypotube 114, which may be made of metal,hard plastic, ceramic, or another suitable rigid material. In some implementations, the introducer 116 and hypotube 114 can be 3D printed with polymeric, metal, or alloy-based materials. If the introducer handle 116 is made of wood, it can be machined and can be attached to the straight hypotube 114 by adhesive or interference fit attachment. On the other hand, if the introducer handle 116 is made of an aluminum alloy, it can be made by die casting, and can be attached to the straight hypotube 114 by adhesive, interference fit attachment, or by welding. The attachment of the introducer handle 116 to the straight hypotube 114 can be configured to ensure no relative movement between the two parts once attached. The first handle 124, the proximal end 136, the second handle 144 and the third handle 154 can be made and be attached to their corresponding tube or rod sections similar to the introducer handle 116.

[0032] Portions of the access tools, including the curved cannula 132, the J-stylet 140, and the straight stylet 150, may be formed of a variety of elastic materials that can be deformed under force and restore their shapes when the deforming force is relieved. For example, the curved tube section 133 of the curved cannula 132 and the distal end portion of the J-stylet 140 need to be straightened when entering the internal channel of the introducer cannula 112, and should curve back to their original curved shape once coming out of the open distal end of the straight hypotube 114 of the introducer cannula 112. Further, when inserted into the internal channel of the curved cannula 132, the distal portion of the rod section 156 of the straight stylet 150 needs to bend along the curved tube section 133, and straightens back once coming out of the open distal end of the curved tube section 133. The flexibility and resilience of an access tool may depend on its dimensions, especially the cross-sectional dimensions, and the material it is made of. In some embodiments, these flexible and resilient portions of the access tools can be made of one or more plastic materials, e.g., polyamide (PA), polyethylene terephthalate (PET), polycarbonate (PC), polyoxymethylene (POM), acrylonitrile butadiene styrene (ABS), polyethylene (PE), polypropylene (PP), and polyimide (PI). In some embodiments, when the cross-sectional dimensions are relatively thick, they can also be made of one or more of the hard plastic elastomers, e.g., polyethylenebased polyolefin elastomers, polypropylene-based elastomers, thermoplastic polyester elastomers, thermoplastic polyurethane elastomers, nitrile butadiene rubber, and thermoplastic vulcanizate polymers. For example, the distal portion of the straight rod 156 can be a solid rod made of a plastic elastomer having a high Shore durometer measurement. In some embodiments, if the resilient tool portions have small cross-sectional dimensions or tubular structure to facilitate bending, they can be made of a semi-rigid materials, because when cross-sectional dimensions are sufficiently small, proper flexibility can be achieved. Further, chevron designs or patterns, or through-thickness slits or holes canbe applied to make a rigid portion more flexible. For example, if the straight tube section 134 and the curved tube section 133 of the curved cannula 132 are made of a hard and rigid material, patterned through-thickness slits can be formed on the distal curved tubular structure to increase flexibility or bendability.

[0033] Also shown in FIG. 1 is the RF ablation device 160, comprising a connection port 164 and a rod section 166 attached to the connection port 164. The rod section 166 comprises a flexible outer wall, e.g., a flexible plastic tubing, housing wires inside to electrically connect the connection port 164 to electrodes at a distal end 162 of the RF ablation device 160. The RF ablation device 160 is configured to apply RF power or energy sufficient to cause ablation or other modulation of tissue (e.g., one or more nerves) for pain relief treatment. The rod section 166 of the RF ablation device 160 can have approximately the same outer diameter as the tube sections 133 and 134 of the J-stylet 140 and the rod 156 of the straight stylet 150, and can be received into the internal channel of the curved cannula 132.

[0034] The one or more access tools and treatment device (e.g., the RF ablation device 160) may include an indicator configured to alert a clinician a current operation state of the treatment device. For example, the indicator may include a light ring disposed along a length of, and extending around a circumference of, the treatment device 160, e.g., within or close to the ablation probe 160.B. Treatment Procedure

[0035] The tool set 100 as shown in FIG. 1 can be used to target a basivertebral nerve inside a vertebral body for the treatment of chronic low back pain. First, the subject patient with chronic low back pain can be examined to determine the specific vertebra or vertebrae that are the source of the chronic low back pain. In accordance with several implementations, target, or candidate, vertebrae for treatment, e.g., one or more of the lumbar vertebrae, sacral vertebrae, cervical vertebrae, or thoracic vertebrae, can be identified prior to treatment. Research has established that Modic changes and associated endplate damage strongly correlate with chronic low back pain. Therefore, one or more visualization modalities (e.g., magnetic resonance imaging (MRI), computer tomography (CT), X-ray, fluoroscopic imaging) may be used to determine whether a vertebral body or vertebral endplate exhibits active Modic characteristics or pre-Modic change characteristics (e.g., characteristics likely to result in Modic changes, such as Type 1 Modic changes, e.g., inflammation and edema, or type 2 Modic changes, e.g., changes in bone marrow and increased visceral fat content). For example, images obtained via MRI may be used to identify (e.g., via application of one or more filters) initial indications or precursors of edema or inflammation at a vertebral endplate prior to a formal characterization or diagnosis as a Type 1Modic change. Accordingly, vertebral bodies may be identified as target candidates for treatment before Modic changes occur (or before painful symptoms manifest themselves to the patient) so that the patients can be proactively treated to prevent, or reduce the likelihood of, chronic low back pain before it occurs. In this manner, the patients will not have to suffer from debilitating lower back pain for a period of time prior to treatment.

[0036] In some implementations, a level of biomarker(s) (e.g., substance P, cytokines, or other compounds associated with inflammatory processes and / or pain) may be obtained from a patient (e.g., through a blood draw or through a sample of cerebrospinal fluid) to determine whether the patient is a candidate for basivertebral nerve ablation treatment. Cytokine biomarker samples may be obtained from multiple different discs or vertebral bodies or foramina of the patient and compared with each other in order to determine the vertebral bodies to target for treatment. Other biomarkers may be assessed as well. In some implementations, samples are obtained over a period of time and compared to determine changes in levels over time. For example, biomarkers may be measured weekly, bi-monthly, monthly, every 3 months, or every 6 months for a period of time and compared to analyze trends or changes over time. If significant changes are noted between the biomarker levels (e.g., changes indicative of pre-Modic, or Modic, changes as described above), treatment may be recommended and performed to prevent or treat back pain. Biomarker levels (e.g., substance P or cytokine protein levels) may be measured using various in vivo or in vitro kits, systems, and techniques (e.g., radio-immunoassay kits / methods, enzyme- linked immunosorbent assay kits, immunohistochemistry techniques, array-based systems, bioassay kits, in vivo injection of an anticytokine immunoglobulin, multiplexed fluorescent microsphere immune-assays, homogeneous time-resolved fluorescence assays, bead-based techniques, interferometers, flow cytometry, etc.). Cytokine proteins may be measured directly or indirectly, such as by measuring mRNA transcripts.

[0037] In some implementations, a target treatment region within a vertebral body may be clarified and pre-selected using pre-operative visualization (e.g., using bilateral fluoroscopy images or both anterior-posterior and lateral fluoroscopy images) of the vertebral body. The target treatment region may be identified as where a tip of a channeling stylet transects a basivertebral foramen (based on the images). The target treatment region may be a location or region between 30% and 50% of the distance between a posterior boundary or wall of the vertebral body and an anterior boundary or wall of the vertebral body. The vertebral body may be of a lumbar vertebra, a sacral vertebra, a thoracic vertebra, or a cervical vertebra. Multiple vertebral bodies may be treated. Nerves within other bones may also be treated.

[0038] The treatment procedure may be monitored by an intraoperative visualization, e.g., fluoroscopic imaging, ultrasonic imaging, CT imaging, or MRI imaging, to live track the treatment progress. A small incision is made on the lower back of a subject patient to be treated. As shown in FIG. 2, the incision may be located on top of a pedicle 214 of a target vertebra 200, which has a vertebral body 210 having a basivertebral nerve 212 therein. A target treatment region 216 is usually pre-identified near the center of the vertebral body 210, where the basivertebral nerve branches to a plurality of axon terminals to innerve the superior and inferior endplates. In some implementations, the target treatment region 216 is in a posterior half of the vertebral body. In some implementations, the target treatment region 216 is between 30% and 50% of the distance between the posterior wall of the vertebral body and the anterior wall of the vertebral body. The introducer assembly 110, as shown in and described with FIG. 1, including the introducer cannula 112 and the introducer stylet 120 assembled together, is inserted into the incision. As such, when impact is received on the first handle 124 from a mallet, the sharp distal tip 122 of the introducer stylet 120 penetrates into the pedicle 214, leading the straight hypotube 114 of the introducer cannula 112 to advance into the pedicle 214, forming a foramen, path, or channel. When it is determined from the monitoring imaging, e.g., fluoroscopic imaging, that the distal end of the straight hypotube 114 of the introducer cannula 112 has reached a predetermined location (e.g., an outer boundary of a vertebral body or a border of cortical bone and cancellous bone of the vertebral body), the introducer stylet 120 is removed from the internal channel of the introducer cannula 112, and the curved cannula assembly 130, including the curved cannula 132 and the J-stylet 140 assembled together, is inserted into the internal channel of the introducer cannula 112.

[0039] As FIG. 3 illustrates, as the curved section 133 of the curved cannula 132 comes out of the open distal end of the straight hypotube 114, it transitions to a curved configuration (e.g., based on its pre-curved shape memory properties or characteristics). Then the second handle 144 is malleted, further driving the distal curved tube section 133 of the curved cannula 132 to advance forward along a curved path, aiming at the target treatment region 216. The sharp distal tip 142 of the rod section of the J-stylet 140 penetrates slightly out of the open distal end of the distal curved tube section 133 of the curved cannula 132, cutting through the bone tissue and causing the open distal end of the distal curved tube section 133 to advance when the second handle 144 is malleted. The direction the distal curved tube section 133 is pointing to can be steered or radially adjusted by turning the second handle 144. The advancement stops when the monitoring imaging shows that the open distal end of the distal curved tube section 133 has reached or almost reached the target treatment region 216, as shown in FIG. 3. To this point, the projected path or channel is formed through the pedicle 214 and into the vertebral body 210by the access tools, e.g., the introducer cannula assembly 110 and the curved cannula assembly 130.

[0040] In FIG. 4, the J-stylet 140 is removed from the internal channel of the curved cannula 132, and the flexible RF ablation device 160 is inserted into the internal channel of the curved cannula 132. When the distal end 162 of the flexible RF ablation device 160 comes out of the open distal end of the curved tube section 133, it is positioned at the target treatment region 216. At this point, RF ablation can be performed. The distal end 162 comprises a bipolar electrode pair to generate radiofrequency (RF) energy that can cause temperature in the cancellous bone tissue around the target treatment region 216 to rapidly rise. The thermal energy may be conducted by heat transfer to the surrounding cancellous bone tissue, thereby heating up the cancellous bone portion. In accordance with several implementations, the thermal energy may be applied within a specific frequency range and having a sufficiently high temperature and over a sufficient duration of time to heat the cancellous bone such that the basivertebral nerve extending through the cancellous bone of the vertebral body is ablated or modulated. In several implementations, the modulation comprises permanent ablation, or denervation, or cellular poration, e.g., electroporation. In some implementations, the modulation comprises temporary denervation or inhibition. In some implementations, the modulation comprises stimulation or denervation without necrosis of tissue.

[0041] For the RF ablation, temperature of the cancellous bone portion surrounding the RF probe 162 (e.g., the target treatment region) may rise to a range from about 70 degrees Celsius to about 115 degrees Celsius (e.g., between 70 degrees Celsius and 85 degrees Celsius, between 75 degrees Celsius and 90 degrees Celsius, between 70 degrees Celsius and 80 degrees Celsius, between 75 degrees Celsius and 85 degrees Celsius, between 80 degrees Celsius and 100 degrees Celsius, between 90 degrees Celsius and 115 degrees Celsius, overlapping ranges thereof, or any value within the recited ranges). The temperature ramp rate may range from 0.1 degrees Celsius / second - 5 degrees Celsius / second. The time of treatment may range from about 10 seconds to about 1 hour (e.g., from 10 seconds to 2 minutes, from 30 seconds to 90 seconds, from 1 minute to 5 minutes, from 2 minutes to 8 minutes, from 5 minutes to 15 minutes, from 10 minutes to 20 minutes, from 15 minutes to 30 minutes, from 30 minutes to 1 hour, overlapping ranges thereof, or any value within the recited ranges). Pulsed energy (e.g., pulsed RF) may be delivered as an alternative to or in sequence with continuous RF energy. For applying radiofrequency energy, the frequency applied may range from 350 kHz to 650 kHz. A power of the radiofrequency energy may range from 5 W to 30 W. In accordance with several implementations, a thermal treatment dose (e.g., using a cumulative equivalent minutes (CEM) 43 degrees Celsius model) is between 200 and 300CEM.

[0042] Back to FIG. 3, as the distal end, including the distal tip 142 of the J -sty let 140, of the curved assembly 130 advances through the pedicle 214 and the cancellous bone issue of the vertebral body 210, the monitoring imaging (e.g., intraoperative fluoroscopy) may indicate that the distal end of the curved assembly 130 will miss the target treatment region 216 (e.g., the desired trajectory needed to reach the target treatment region 216 will be off). For example, the projected path or trajectory of the distal end of the distal curved tube section 133 may be below (e.g., too posterior of) the target treatment region 216, or undershooting, as shown in FIG. 5. This undershooting may be due to, for example, the penetration direction of the straight hypotube 114 into the pedicle 214 being slightly off, the penetration distance of the straight hypotube 114 into the pedicle 214 being not deep enough, and / or the curvature of the distal curved tube section 133 being slightly sharper than projected (e.g., due to low density of osteopenic or osteoporotic bone). In this case, the advancement of the curved cannula assembly 130 may be ended or stopped prior to full advancement or may be retracted a short distance and the J-stylet 140 may be removed from the internal channel of the curved cannula 132. In some implementations, the straight stylet 150 is then inserted into the internal channel of the curved cannula 132. When the distal tip 152 of the straight stylet 150 penetrates through the open distal end of the curved cannula 132, it straightens out and advances forward in a straight path rather than following the curved trajectory of the distal curved tube section 133. Since no further curvature is added to the distance between the open distal end of the distal curved tube section 133 and the target treatment region 216, the distal tip 152 of the straight stylet may arrive at the target treatment region 216, correcting the undershooting issue, as shown in FIG. 5. At this point, the straight stylet 150 is removed from the curved cannula 132, and the RF ablation device 160 is inserted for ablation treatment.

[0043] Because the use of the straight stylet adds an additional tool exchange that adds time to the overall procedure, many clinicians may choose to skip the step of inserting the straight stylet in situations of undershooting and simply try to use the flexible RF ablation device 160 to achieve the straight path beyond the open distal end of the curved cannula 132. However, this can result in damage to the flexible RF ablation device and may still not result in placement at the target treatment region, which may result in ineffective ablation of the basivertebral nerve, meaning that the patient may still experience back pain.C. Integrated RF Device

[0044] In accordance with several embodiments, including a straight stylet 150 in each tool set 100 can bear an undesired extra cost of goods and medical waste. In addition, as indicated previously,the insertion of the straight stylet 150 adds another tool exchange that increases the overall duration of the treatment procedure. In accordance with several embodiments, it is advantageous if the RF ablation device 160 has increased strength and durability such that it is capable of further penetrating though cancellous bone tissue without a path having been previously formed by another channeling instrument. In this way, the steps shown in FIG. 5, including inserting the straight stylet 150 into the curved cannula 132 and removing the straight stylet 150 from the curved cannula 132, can be eliminated. However, the RF ablation device 160 as constructed and shown in FIG. 1, may not be suitable for performing such a task. For example, the RF ablation device 160 is not malletable, or capable of being malleted, because there is no proximal surface configured to receive a mechanical impact of a mallet and the rod section 166 is flexible and not adapted to transfer mechanical impact to advance the distal tip 162 through bone tissue. In addition, the distal tip 162 may break off under impact and may be difficult to retrieve from the patient.

[0045] FIG. 6 shows an elevation view of an example embodiment of an integrated RF ablation device 170 having a straight elongate shaft, tube, or rod comprising a proximal rigid section 176 disposed between a proximal malletable handle 174 and a resilient portion 190. The resilient portion 190 is disposed proximal of a distal end portion 180, which comprises an RF electrode or probe head 172 at a distal tip. The rigid section 176 may be made of a rigid material, e.g., metal, hard plastic, ceramic, polymeric, or composite material, in order to transfer mechanical movement and impact upon malleting of the proximal handle 174. The resilient portion 190 is constructed to be flexible and resilient, so that it can be curved to advance through the distal curved tube section 133 of the curved cannula 132 and is also able to restore its straight shape once the resilient portion 190 is no longer acted upon [e.g., by being constrained within the distal curved tube section 133 of the curved cannula 132). In some implementations, the distal resilient portion 190 may be pre-curved to have a slight curve in a resting state when not acted upon by any force or constraint (e.g., via shape memory material and heat setting). The proximal handle 174 may be made of plastic, polymer, wood, or aluminum alloy, and can be attached to the rigid section 176 of the elongate shaft, tube, or rod by insert molding, adhesive, interference attachment, welding, or another suitable method, similar to the attachment methods described above in connection with FIG. 1. By attachment, the proximal handle 174 is affixed to the rigid section 176 so that turning or rotating the proximal handle 174 causes the elongate shaft, tube or rod including rigid section 176 to turn or rotate also. The proximal handle 174 comprises a connection port (not shown) to facilitate electrical connections to an energy source (not shown), such as a radiofrequency generator. The connection portion (not shown) may be located at a handle head surface (to the right side in FIG. 6), or at a side surface of the handle 174. When located at the handle head surface, the connection port isdesirably recessed, so that it is not damaged from the impact of a mallet. In some implementations, the connection port is not utilized until after the integrated RF ablation device 170 has been advanced to a final position prior to activation. The connection port may comprise, for example, a pogo or spring-loaded electrical connector or may comprise other conductive materials or types of electrical connection ports. The connection port may include an O-ring seal or other sealing mechanism to prevent blood from entering the handle 174.

[0046] FIG. 7 is a side cross-sectional view revealing the internal structure of the distal end portion 180 and part of the resilient portion 190 of the RF ablation device 170 shown in FIG. 6. As can be seen, a distal RF electrode 172 comprises a bullet-shaped, bull-nosed, or otherwise rounded, beveled or bevel-tipped, tapered, or chamfered probe head made of an electrically conductive (e.g., metallic) material, which has the advantage of being adapted for traversing a path through cancellous bone tissue. Inside the distal RF electrode 172 is shown that one or more electrical conductors or wires 186 is attached, e.g., by welding, to the distal RF electrode 172, making the distal RF electrode 172 one of a bipolar electrode pair. The one or more electrical conductors or wires extend from the distal RF electrode 172 to the proximal handle 174, and are connected to the energy source (e.g., RF generator) via the connection port. A portion of the resilient section 190 (e.g., a portion that is not coated by insulation) of the hypotube 182 forms the other "electrode" of the bipolar electrode pair, as shown in FIG. 7. The distal end of the hypotube 182 or the resilient section 190 may be spaced approximately 2 mm (or other appropriate distance) from the proximal end of the distal tip electrode 172. During an ablation treatment procedure, high-frequency current flows between the two electrodes to generate thermal energy (heat) to the surrounding cancellous bone tissue. The outer hypotube 182 may extend to cover the entire length of the elongate shaft, tube, or rod, including the rigid section 176 and the resilient section 190. Inside the hypotube 182 may be an insulation layer 188, which may be in the form of an inner tube made of an insulation material, holding the one or more conductors or wires 186 inside and insulating the one or more conductors or wires from the hypotube 182. The plurality of electrical wires 186 may be braided to form an integrated braided cable that extends inside and along the insulation layer 188 connecting the distal RF electrode 172 to the connection port (not shown) on the proximal handle 174. In some implementations, the insulation layer 188 is a flexible plastic extrusion, e.g., an extruded tubing made of low density polyethylene (LDPE), polyimide, polyamide (PA), polyvinyl chloride (PVC), silicone, or polyurethane. In some implementations, the insulation layer 188 may be coated on to the core of braided wires 186. In some implementations, the insulation layer 188 is formed by anodization. In some implementations, the insulation layer 188 may be a heat shrink tubing, e.g., made ofpolytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), or a block copolymer such as PEBAX®, shrunk to the braided wires 186. In some implementations, the braided cable may be replaced with a nitinol core or other structure. A temperature sensor 184, e.g., a thermocouple or a thermistor, may be included inside the hypotube 182, configured to measure a temperature of the RF electrode 172 and / or the surrounding bone issue. One or more additional temperature sensors may also be positioned at various additional locations along the RF ablation device. The distal RF electrode 172 may be attached to the hypotube 182 of the resilient portion 190 by a joint section 185, which may be potted by an adhesive, e.g., epoxy, forming an interconnecting neck structure. Alternatively, the joint section 185 may be a pre-manufactured ring connected by interference fit, adhesive, or welding. The joint section 185 insulates and electrically isolates the distal RF electrode 172 from the conductive portion of the hypotube 182 forming the other electrode and is strong and durable enough to tolerate impact and bending.

[0047] The hypotube 182 of the resilient portion 190 is shown in FIG. 8 as a detailed elevation view. As can be seen, slits 192 are formed on the wall of the hypotube 182. Each of the slits 192 has a length that is significantly greater than a width, and the length direction of the slit is substantially perpendicular to a longitudinal axis of the hypotube 182, which is in the length direction of the hypotube 182. The slits 192 can be in other shapes, e.g., round or square holes, or a combination of different shapes. The slits 192 may be formed through a partial thickness or full thickness of the hypotube 190 and can also take a chevron pattern or another pattern around the circumference of the hypotube 182. The outer surface of the hypotube 182 can be made of a nickel titanium alloy (e.g., Nitinol), stainless steel, or another type of electrical conductor, e.g., spring steel, molded or extruded plastics doped with conductive material. In some implementations, only a distal portion of the hypotube 182 (e.g., the distal-most 4 mm or other appropriate length) is conductive and not the entire length of the resilient portion 190 or the hypotube 182 (e.g., the rest of the length is covered or coated with an insulation layer such as a dielectric or heat-shrink coating). The slits 192 can be formed by laser cutting, machining, rolling or another type of suitable forming method. Such an arrangement of the slits 192 may be adapted to weaken the hypotube 182 so that bending of the hypotube 182 in all directions is uniformly promoted or such that bending is facilitated in one direction or two opposite directions. In some embodiments, the hypotube 182 of the whole elongate shaft, tube, or rod, including the distal resilient section 190 and the proximal rigid section 176 is made of the same rigid and conductive material. The slits 192 are formed on the resilient section 190 only, allowing bending of the resilient section 190 easier but keeping the remaining rigid section 176 rigid. In some embodiments, the proximal rigid section 176 is covered by an insulation layer. In some embodiments, the hypotube 182 of the resilient section 190 can comprise a more flexibleconductive material as compared to the more rigid section 176 to the end connecting the proximal handle 174 of the integrated RF ablation device 170.

[0048] Properly constructed, during an ablation procedure when the situation of FIG. 5 may happen, e.g., the projected path or trajectory of the curved cannula 132 (shown by the dashed line) is under shooting (or going too posterior) the target treatment region 216 which is normally about 30% to 50% of the distance between the posterior wall of the vertebral body and the anterior wall of the vertebral body. Then, the advancement of the curved cannula 132 is terminated or stopped before the open distal end reaches the target treatment region 216, or the curved cannula 132 is retracted. The J -sty I et 140 may be removed from the internal channel of the curved cannula 132. Then, the integrated RF ablation device 170 may be inserted into the internal channel of the curved cannula 132. When the distal RF electrode 172 of the integrated RF device 170 penetrates through the open distal end of the curved cannula 132, it transitions to a straight shape and follows a straight or generally straight path toward the target treatment region 216. No further curvature is added to the advancement path between the open distal end of the distal curved tube section 133 of the curved cannula 132 and the target treatment region 216. As such, the distal RF electrode 172 may advantageously arrive at the target treatment region 216, reflecting the state shown in FIG. 5. At this point, RF ablation of the basivertebral nerve or other intraosseous nerves can be performed. As such, the extra steps of inserting and removing the straight stylet 150 can advantageously be eliminated.

[0049] In some embodiments, the integrated RF device 170 may be constructed with a rigid elongate shaft, tube, or rod that is rigid along its entire length without any laser cuts for flexibility or bending. This means that both the proximal section 176 and the distal section 190 of the elongate shaft, tube, or rod are rigid. For example, the entire elongate shaft, tube, or rod, including both the proximal section 176 and the distal section 190 (which is described above has resilient or flexible and in this embodiment would be rigid), may be made of nitinol tubing or rod, springs, doped molded or extruded plastics, stainless steel, or other metal or metallic alloy. In some configurations, neither the proximal section 176 nor the distal section 190 comprises stiffness-weakening slits, cuts, or other features. The integrated device 170 with a rigid elongate shaft, tube or rod as described herein may have the advantage of forming a straight channel in a bone, e.g., a vertebra. In some embodiments, the integrated RF device 170 comprises a solid straight access probe with a sharpened bevel / diamond tip that allows for access and ablation. The integrated RF device 170 may comprise an inner hypotube that is laser welded to the distal tip electrode and an outer ring electrode hypotube, wherein the inner and outer hypotubes are electrically insulated from each other. As discussed previously, all but a distal-most portion forming theouter ring electrode of the outer hypotube may be coated with an insulation layer or coating. In some implementations, the distal section 190 could be formed with a pre-curved shape having a slight curve or bend instead of being completely straight.D. Conclusion

[0050] In some implementations, the system comprises various features that are present as single features (as opposed to multiple features). For example, in one embodiment, the system includes a single radiofrequency generator, a single introducer cannula with a single stylet, a single curved cannula with a single J-stylet, a single radiofrequency energy delivery device or probe, and a single bipolar pair of electrodes. A single thermocouple (or other means for measuring temperature) may also be included. Multiple features or components are provided in alternate embodiments.

[0051] In some implementations, the system comprises one or more of the following: means for tissue modulation (e.g., an ablation or other type of modulation catheter or delivery device), means for monitoring temperature (e.g., thermocouple, thermistor, infrared sensor), means for imaging (e.g., MRI, CT, fluoroscopy), means for accessing (e.g., introducer assembly, curved cannulas, drills, curettes), etc.

[0052] Although certain embodiments and examples have been described herein, aspects of the methods and devices shown and described in the present disclosure may be differently combined and / or modified to form still further embodiments. Additionally, the methods described herein may be practiced using any device suitable for performing the recited steps. Further, the disclosure (including the figures) herein of any particular feature, aspect, method, property, characteristic, quality, attribute, element, or the like in connection with various embodiments can be used in all other embodiments set forth herein. The section headings used herein are merely provided to enhance readability and are not intended to limit the scope of the embodiments disclosed in a particular section to the features or elements disclosed in that section.

[0053] While the embodiments are susceptible to various modifications, and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the embodiments are not to be limited to the particular forms or methods disclosed, but to the contrary, the embodiments are to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the various embodiments described and the appended claims. Any methods disclosed herein need not be performed in the order recited. The methods disclosedherein include certain actions taken by a practitioner; however, they can also include any third-party instruction of those actions, either expressly or by implication. For example, actions such as "applying thermal energy" include "instructing the application of thermal energy."

[0054] Various embodiments of the disclosure have been presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention. The ranges disclosed herein encompass any and all overlap, sub-ranges, and combinations thereof, as well as individual numerical values within that range. For example, description of a range such as from 70 to 115 degrees should be considered to have specifically disclosed subranges such as from 70 to 80 degrees, from 70 to 100 degrees, from 70 to 110 degrees, from 80 to 100 degrees, etc., as well as individual numbers within that range, for example, 70, 80, 90, 95, 100, 70.5, 90.5, and any whole and partial increments therebetween. Language such as "up to," "at least," "greater than," "less than," "between," and the like includes the number recited. Numbers preceded by a term such as "about" or "approximately" include the recited numbers. For example, "about 10" includes "10." For example, the terms "approximately", "about", and "substantially" as used herein represent an amount close to the stated amount that still performs a desired function or achieves a desired result.

Claims

WHAT IS CLAIMED IS:

1. A device for performing radiofrequency (RF) ablation of one or more nerves within a vertebral body, comprising: a handle at a proximal end, the handle sized and adapted to receive a mechanical impact from a mallet; a distal tip electrode at a distal end; an elongate tube extending from the handle to the distal end, the elongate tube having a distal resilient section, wherein a portion of the resilient section comprises a conductive material configured to function as a second electrode of a bipolar electrode pair with the distal tip electrode; and an insulating joint section positioned between the distal electrode and a distal end of the elongate tube.

2. The device of Claim 1, wherein the elongate tube further comprises a proximal rigid section disposed between the distal resilient section and the handle.

3. The device of Claim 2, wherein the at least a portion of the proximal rigid section is covered by an insulation layer.

4. The device of Claim 2 or 3, wherein the elongate tube is affixed to the handle.

5. The device of any of Claims 2 to 4, wherein the handle comprises an electrical connection port.

6. The device of Claim 5, wherein the connection port is located at a handle head surface.

7. The device of Claim 6, wherein the connection port is recessed within the handle head surface.

8. The device of any of Claims 2 to 7, wherein the elongate tube comprises a hypotube made of a rigid conductive material, and wherein the resilient section of the elongate tube has slits formed on the hypotube.

9. The device of Claim 8, wherein the hypotube is connected to the insulation joint.

10. The device of Claim 8 or 9, wherein the rigid conductive material is a nickel titanium alloy.

11. The device of any of Claims 8 to 10, wherein the slits are formed through at least a partial thickness of the hypotube.

12. The device of any of Claims 8 to 11, wherein the slits have a length that is significantly larger than a width.

13. The device of Claim 12, wherein the length direction of the slits are arranged substantially perpendicular to a longitudinal axis of the hypotube.

14. The device of any of Claims 8 to 13, wherein the slits are arranged in a chevron pattern.

15. The device of any of Claims 2 to 14, wherein the resilient section is made of a flexible and resilient material.

16. The device of any of Claims 2 to 14, wherein the rigid section is made of a hard and rigid material.

17. The device of any preceding claim, wherein the distal tip electrode comprises a bullet-shaped configuration or a bevel-tipped configuration at the distal end.

18. The device of Claim 5, wherein a plurality of electrical wires extends within the elongate tube connecting the distal electrode to the connection port at the handle.

19. The device of Claim 18, wherein the plurality of electrical wires are braided to form an integrated braided cable.

20. The device of Claim 18, wherein a nitinol rod or core extends within the elongate tube connecting the distal tip electrode to the connection port at the handle.

21. The device of Claim 18 or 19, wherein the plurality of electrical wires are surrounded by an insulation layer.

22. The device of any preceding claim, wherein the distal resilient section is configured to bend but to remain straight when not caused to bend.

23. The device of any of Claims 1 to 21, wherein the distal resilient section is pre-curved to have a slight curve.

24. A device for performing radiofrequency (RF) ablation of one or more nerves within a vertebral body, comprising: a handle at a proximal end, the handle sized and adapted to receive a mechanical impact from a mallet; a distal tip electrode at a distal end; an elongate tube extending from the handle to the distal end, the elongate tube having a distal section, wherein a portion of the distal section comprises a conductive material configured to function as a second electrode of a bipolar electrode pair with the distal tip electrode; and an insulating joint section positioned between the distal electrode and a distal end of the elongate tube.

25. The device of Claim 24, wherein the elongate tube further comprises a proximal rigid section disposed between the distal section and the handle.

26. The device of Claim 25, wherein the distal section is made of a rigid material.

27. The device of Claim 24, wherein the distal section is flexible.

28. The device of Claim 26 or 27, wherein the distal section is pre-formed having a straight shape.

29. The device of Claim 26 or ' l , wherein the distal section is pre-formed having a slight curve.

30. A method of ablating a nerve within a vertebral body of a subject, the method comprising: forming a curved path in the vertebral body with a curved cannula assembly, the curved path being directed toward a pre-selected target treatment region; monitoring formation of the curved path using an intraoperative imaging modality; removing a J-stylet from an internal channel in a curved cannula of the curved cannula assembly; inserting an integrated radiofrequency (RF) ablation device into the internal channel of the curved cannula, and advancing a distal end of the RF ablation device out of an open distal end of the curved cannula in a straight path; determining if the straight path reaches the pre-selected target treatment region using the intraoperative imaging modality; and performing RF ablation with the RF ablation device.

31. The method of Claim 30, wherein the intraoperative imaging modality is fluoroscopic imaging.

32. The method of Claim 30 or 31, wherein the integrated RF ablation device comprises: a bipolar RF probe comprising an elongate tube having a resilient distal section, the resilient section configured to flex but to remain straight when not being caused to flex; a distal tip electrode; an insulating joint section between the distal end of the resilient distal section and the distal tip electrode, wherein at least a portion of the elongate tube proximal to the insulating joint section comprises conductive material adapted to form a bipolar electrode pair with the distal tip electrode; and a handle at the proximal end, the handle attached to a proximal end of the elongate tube.

33. The method of Claim 32, wherein the handle is capable of receiving a mechanical impact (e.g., from a mallet).

34. The method of Claim 32 or 33, wherein the elongate tube further comprises a rigid section disposed between the resilient section and the handle.

35. The device of Claim 34, wherein at least a portion of the rigid section is covered by an insulation layer.

36. The method of any of Claims 32 to 35, wherein the elongate tube is affixed to the handle.

37. The method of any of Claims 32 to 36, wherein the handle comprises an electrical connection port.

38. The method of Claim 34, wherein the elongate tube comprises a hypotube made of a rigid conductive material, and wherein the resilient section of the elongate tube has slits formed on the hypotube adapted to facilitate flexing of the resilient section.

39. The method of Claim 38, wherein the slits are formed through at least a partial thickness of the hypotube.

40. The method of Claim 30, wherein the slits have a length that is significantly greater than a width.

41. The method of Claim 40, wherein the length direction of the slits are arranged substantially perpendicular to a longitudinal axis of the hypotube.

42. The method of Claim 37, wherein a plurality of electrical wires extends within the elongate tube connecting the distal tip electrode to the electrical connection port at the handle.

43. The method of Claim 42, wherein the plurality of electrical wires are braided together to form a braided cable.

44. The method of Claim 42 or 43, wherein the plurality of electrical wires are surrounded by an insulation layer.

45. The method of any of Claims 32 to 44, wherein the RF probe comprises a bullet shaped probe head or a bevel-tipped probe head.

46. A kit for accessing and ablating one or more nerves within a vertebral body, the kit comprising: an introducer assembly comprising an introducer cannula and an introducer stylet, the introducer assembly adapted to form a straight access path through a pedicle to a border of a vertebral body; a curved cannula assembly comprising a curved cannula with a pre-curved distal end and a J-stylet with a pre-curved distal end corresponding to the pre-curved distal end of the curved cannula; the curved cannula assembly adapted to form a curved path from the straight accesspath toward a predetermined target treatment region within a cancellous bone portion of a vertebral body; and an integrated radiofrequency ablation probe comprising: a handle at a proximal end, the handle sized and adapted to receive a mechanical impact from a mallet; a distal tip electrode at a distal end; an elongate tube extending from the handle to the distal end, the elongate tube having a distal resilient section, wherein a portion of the resilient section comprises a conductive material configured to function as a second electrode of a bipolar electrode pair with the distal tip electrode; and an insulating joint section positioned between the distal tip electrode and a distal end of the elongate tube.

47. The kit of Claim 46, wherein the distal resilient section of the integrated radiofrequency ablation probe is configured to bend when inserted through the curved cannula but to remain straight advanced out of an open distal end of the curved cannula.

48. The kit of Claim 46, wherein the distal resilient section of the integrated radiofrequency ablation probe is configured to have a pre-curved shape when in a resting configuration.

49. An integrated radiofrequency ablation device as described and illustrated herein.

50. A kit of tools for accessing and ablating one or more nerves within a vertebral body as described and illustrated herein.

51. A method of accessing and ablating one or more nerves within a vertebral body as described and illustrated herein.

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