Patent Application
20240415539
Described herein are various implementations of systems and methods for accessing and/or modulating tissue (for example, systems and methods for accessing and/or ablating nerves or other tissue within or surrounding a vertebral body to treat chronic lower back pain). Systems or kits of access tools for accessing target treatment locations within vertebral bodies are also provided. The access tools may include, for example, a curved J-stylet configured for easy removal from a curved cannula while still providing sufficient curved trajectory to reach a target treatment location within vertebral bodies at varying vertebral levels of the spine and having varying bone density.
Back pain is a very common health problem worldwide and is a major cause for work-related disability benefits and compensation. At any given time, low back pain impacts nearly 30% of the US population, leading to 62 million annual visits to hospitals, emergency departments, outpatient clinics, and physician offices. Back pain may arise from strained muscles, ligaments, or tendons in the back and/or structural problems with bones or spinal discs. The back pain may be acute or chronic. Existing treatments for chronic back pain vary widely and include physical therapy and exercise, chiropractic treatments, injections, rest, pharmacological therapy such as opioids, pain relievers or anti-inflammatory medications, and 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.
Applicant's existing technology (the Intracept® procedure by Relievant®) offers a safe and effective minimally invasive procedure that targets the basivertebral nerve for the relief of chronic vertebrogenic low back pain. As disclosed herein, several embodiments provide bone access tools, additional modalities of relief for patients and/or adjunct technologies.
In accordance with several embodiments, an introducer system may include an introducer assembly comprising an introducer cannula and an introducer stylet. The introducer stylet may be bevel tipped, trocar tipped, and/or diamond tipped. The introducer stylet is configured to be received in a lumen of the introducer cannula in a manner such that a distal tip of the introducer stylet protrudes from an open distal tip of the introducer cannula thereby forming the introducer assembly in combination.
In accordance with several embodiments, the introducer system may further include a curved cannula assembly. The curved cannula assembly may include a cannula comprising a proximal handle with a curved insertion slot and a distal polymeric tube. The distal polymeric tube may include a curved distal end portion having a preformed curvature but configured to transition to a generally straight configuration when placed under constraint (e.g., constraint by insertion through a straight introducer cannula). The curved cannula assembly may further include a stylet (e.g., a J-stylet) comprising a proximal handle and a distal elongate shaft. The distal elongate shaft includes a curved distal end portion having a preformed curvature but configured to transition to a generally straight configuration when placed under constraint (e.g., constraint by insertion through a cannula) and a distal channeling tip. A length of the curved distal end portion of the distal elongate shaft proximal to the distal channeling tip (e.g., a springboard or platform portion) may comprise a cross-section circumference profile that is less than a full cross-section circumference profile (e.g., cross-section circumference profile of neighboring or adjacent portions of the distal elongate shaft or of the distal channeling tip), such that there is a larger gap between an outer cross-sectional dimension of the curved distal end portion of the distal elongate shaft and the inner diameter of the curved distal end portion of the cannula along the length of the curved distal end portion of the distal elongate shaft proximal to the distal channeling tip. The less than full (e.g., less than circular) cross-section circumference profile may comprise a “D” shape (e.g., as opposed to a full “O” shape). The overall cross-section circumference profile of the curved distal end portion of the distal elongate shaft may thus be asymmetric (e.g., not uniform or constant along its entire length).
In accordance with several embodiments, the curved distal end portion of the J-stylet may be constructed for easy retraction from the curved cannula when the J-stylet is fully received into the curved cannula lumen during a procedure. The curved distal end portion of the J-stylet may have a section of reduced thickness that is about 20%-80% (e.g., 20%-60%, 30%-70%, 40%-80%, or overlapping ranges thereof) of the full circumferential thickness of the distal elongate shaft of the J-stylet. The reduced thickness may be achieved by removing part of material of the curved distal end portion. In some embodiments, the curved distal end portion may have a sloped transition section between a reduced thickness section and the distal channeling tip. In some embodiments, the reduced thickness may not be uniform from a proximal end to a distal end of the curved distal end portion. The reduced thickness section may taper down from the proximal end to the distal end of the curved distal end portion. Alternatively, the reduced thickness section may taper down from the distal end to the proximal end of the curved distal end portion. In other embodiments, the curved distal end portion of the J-stylet may have a slit formed along a length direction of the distal elongate shaft separating a flexible curved section at an outer curvature side of the curved distal end portion and a flexible extension at the inner curvature side of the curved distal end portion. The flexible extension may extend covering a partial length of the flexible curved section. Alternatively, the flexible extension may extend covering a full length of the flexible curved section. In some embodiments, the curved distal end portion of the J-stylet may have a plurality of slots formed vertical to the length direction of the distal elongate shaft at an outer curvature side of the curved distal end portion. A cutout may be formed at the outer curvature of the curved distal end portion at a proximal end of the curved distal end portion. In some embodiments, the distal open tip of curved cannula may have a beveled or angled tip (e.g., a bevel that is substantially parallel to a bevel of a distal channeling tip of the J-stylet when the J-stylet is received into the curved cannula lumen).
In Example 1, a medical device for forming a channel into a bone, comprising an introducer cannula having a hypotube disposed in a longitudinal direction, the distal hypotube having an introducer lumen disposed therethrough; a curved cannula having an elongated tube, the elongated tube having a curved cannula lumen disposed therethrough, the elongated tube having a proximal straight tube portion and a distal curved tube portion, the elongated tube configured to be received into the introducer lumen of the introducer cannula; and a stylet having an elongated shaft, the elongated shaft having a proximal straight portion and a distal curved portion, the elongated shaft configured to be received into the curved cannula lumen; wherein the distal curved portion of the stylet is constructed for retraction from the curved cannula when the stylet is received into the curved cannula lumen.
In Example 2, the device of Example 1, wherein the distal curved portion of the stylet has a section of reduced thickness.
In Example 3, the device of Example 2, wherein the section of reduced thickness is 40%-80% of the full circumferential thickness of the elongated shaft.
In Example 4, the device of Examples 2 or 3, wherein the section of reduced thickness is formed by removing material from at least a region of the distal curved portion.
In Example 5. the device of any of Examples 1-4, wherein the distal curved portion has a radiused or sloped transition section between the section of reduced thickness and a distal channeling tip.
In Example 6, the device of Examples 2 or 3, wherein the section of reduced thickness is not uniform from a proximal end to a distal end of the distal curved portion.
In Example 7, the device of Example 6, wherein the reduced thickness tapers from the proximal end to the distal end of the distal curved portion.
In Example 8, the device of Examples 6 or 7, wherein the reduced thickness tapers from the distal end to the proximal end of the distal curved portion.
In Example 9, the device of Example 1, wherein the distal curved portion of the stylet has a slit formed along a length direction of the elongated shaft separating a flexible curved section at an outer curvature side of the distal curved portion and a flexible extension at the inner curvature side of the distal curved portion.
In Example 10, the device of Example 9, wherein the flexible extension extends along a partial length of the flexible curved section.
In Example 11, the device of Examples 9 or 10, wherein the flexible extension extends along a full length of the flexible curved section.
In Example 12, the device of Example 1, wherein the distal curved portion of the stylet has a plurality of slots formed perpendicular to the length direction of the elongated shaft at an outer curvature side of the distal curved portion.
In Example 13, the device of Example 12, wherein a cutout is formed at the outer curvature of the distal curved portion at a proximal end of the distal curved portion.
In Example 14, the device of Examples 1-13, wherein a distal open tip of curved cannula is a beveled tip.
In Example 15, the device of Example 1, wherein the distal curved tube portion is configured to be flexible and resilient.
In Example 16, a medical device for forming a channel into a bone, comprising: an introducer cannula having a hypotube disposed in a longitudinal direction, the distal hypotube having an introducer lumen disposed therethrough; a curved cannula having an elongated tube, the elongated tube having a curved cannula lumen disposed therethrough, the elongated tube having a proximal straight tube portion and a distal curved tube portion, the elongated tube configured to be received into the introducer lumen of the introducer cannula; and a stylet having an elongated shaft, the elongated shaft having a proximal straight portion and a distal curved portion, the elongated shaft configured to be received into the curved cannula lumen, wherein the distal curved portion of the stylet is relieved from a generally cylindrical shape of the stylet.
In Example 17, the device of Example 16, wherein the distal curved portion of the stylet has a plurality of slots formed perpendicular to the length direction of the elongated shaft at an outer curvature side of the distal curved portion.
In Example 18, the device of Example 16, wherein the distal curved portion of the stylet has a section of reduced thickness.
In Example 19, the device of Example 18, wherein the section of reduced thickness is 40%-80% of the full circumferential thickness of the elongated shaft.
In Example 20, the device of Example 18, wherein the section of reduced thickness is formed by removing material from at least a region of the distal curved portion.
In Example 21, the device of Example 18, wherein the distal curved portion has a radiused or sloped transition section between the section of reduced thickness and a distal channeling tip.
In Example 22, the device of Example 18, wherein the section of reduced thickness is not uniform from a proximal end to a distal end of the distal curved portion.
In Example 23, the device of Example 22, wherein the reduced thickness tapers from the proximal end to the distal end of the distal curved portion.
In Example 24, the device of Example 22, wherein the reduced thickness tapers from the distal end to the proximal end of the distal curved portion.
In Example 25, the device of Example 16, wherein the distal curved portion of the stylet has a slit formed along a length direction of the elongated shaft separating a flexible curved section at an outer curvature side of the distal curved portion and a flexible extension at the inner curvature side of the distal curved portion.
In Example 26, the device of Example 25, wherein the flexible extension extends along a partial length of the flexible curved section.
In Example 27, the device of Example 25, wherein the flexible extension extends along a full length of the flexible curved section.
In Example 28, the device of Example 27, wherein a cutout is formed at the outer curvature of the distal curved portion at a proximal end of the distal curved portion.
In Example 29, the device of Example 16, wherein a distal open tip of curved cannula is a beveled tip.
In Example 30, a medical device for accessing and treating tissue within a vertebral body, comprising an introducer cannula having an introducer lumen disposed therethrough, a curved cannula having a proximal straight tube portion and a distal curved tube portion, the elongated tube configured to be received into the introducer lumen of the introducer cannula; and a stylet having an elongated shaft, the elongated shaft having a proximal straight portion and a distal curved portion, the elongated shaft configured to be received into the curved cannula lumen, a radiofrequency probe configured to be advanced through the curved cannula lumen to a target treatment location; and a radiofrequency energy generator connected to the radiofrequency probe and configured to provide radiofrequency energy to the radiofrequency probe to treat the tissue, wherein the distal curved portion of the stylet is relieved from a generally cylindrical shape of the stylet.
In Example 31, the device of Example 30, wherein the radiofrequency probe is a flexible bipolar probe.
In Example 32, the device of Example 30, wherein the distal curved portion of the stylet has a plurality of slots formed perpendicular to the length direction of the elongated shaft at an outer curvature side of the distal curved portion.
In Example 33, the device of Example 30, wherein a distal open tip of curved cannula is a beveled tip.
In Example 34, a medical device for forming a channel into a bone, comprising an introducer cannula having a hypotube disposed in a longitudinal direction, the distal hypotube having an introducer lumen disposed therethrough, a curved cannula having an elongated tube, the elongated tube having a curved cannula lumen disposed therethrough, the elongated tube having a proximal straight tube portion and a distal curved tube portion, the elongated tube configured to be received into the introducer lumen of the introducer cannula, and a stylet having an elongated shaft, the elongated shaft having a proximal straight portion and a distal curved portion, the elongated shaft configured to be received into the curved cannula lumen, wherein the distal curved portion of the stylet has a plurality of slots formed perpendicular to the length direction of the elongated shaft.
In Example 35, the device of Example 34, wherein the plurality of slots are located at an outer curvature side of the distal curved portion
For purposes of summarizing the disclosure, certain aspects, advantages, and novel features of embodiments of the disclosure have been described herein. It is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment of the disclosure provided herein. Thus, the embodiments disclosed herein may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught or suggested herein without necessarily achieving other advantages as may be taught or suggested herein.
The 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 “applying thermal energy” include “instructing the applying of thermal energy.” 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.
Several embodiments of the disclosure will be more fully understood by reference to the following drawings which are for illustrative purposes only:
Several implementations described herein are directed to systems and methods for modulating nerves within or adjacent (e.g., surrounding) bone. In some implementations, an intraosseous nerve (e.g., basivertebral nerve) within a bone (e.g., vertebral body) of the spine is modulated for treatment, or prevention, of chronic back pain. The vertebral body may be located in any level of the vertebral column (e.g., cervical, thoracic, lumbar and/or sacral).
In some implementations, the one or more nerves being modulated are extraosseous nerves located outside the vertebral body or other bone (e.g., at locations before the nerves enter into, or after they exit from, a foramen of the bone). Other tissue in addition to, or alternative to, nerves may also be treated or otherwise affected (e.g., tumors or other cancerous tissue or fractured bones). Portions of nerves within or on one or more vertebral endplates or intervertebral discs between adjacent vertebral bodies may be modulated.
The modulation of nerves or other tissues may be performed to treat one or more indications, including but not limited to chronic low back pain, upper back pain, acute back pain, joint pain, tumors in the bone, and/or bone fractures. The modulation of nerves may also be performed in conjunction with bone fusion or arthrodesis procedures so as to provide synergistic effects or complete all-in-one, “one-and-done” treatment that will not require further surgical or minimally invasive interventions.
In some implementations, fractures within the bone may be treated in addition to denervation treatment and/or ablation of tumors by applying heat or energy and/or delivering agents or bone filler material to the bone. For example, bone morphogenetic proteins and/or bone cement may be delivered in conjunction with vertebroplasty or other procedures to treat fractures or promote bone growth or bone healing. In some implementations, energy is applied and then agents and/or bone filler material is delivered in a combined procedure. In some aspects, vertebral compression fractures (which may be caused by osteoporosis or cancer) are treated in conjunction with energy delivery to modulate nerves and/or cancerous tissue to treat back pain.
In accordance with several implementations, the systems and methods of treating back pain or facilitating neuromodulation of intraosseous nerves described herein can be performed without surgical resection, without general anesthesia, without cooling (e.g., without cooling fluid), and/or with virtually no blood loss. In some embodiments, the systems and methods of treating back pain or facilitating neuromodulation of intraosseous nerves described herein facilitate easy retreatment if necessary. In accordance with several implementations, successful treatment can be performed in challenging or difficult-to-access locations and access can be varied depending on bone structure or differing bone anatomy. One or more of these advantages also apply to treatment of tissue outside of the spine (e.g., other orthopedic applications or other tissue).
Various methods of access may be used to access a vertebral body or other bone. In some implementations, the vertebral body is accessed transpedicularly (through one or both pedicles). In other implementations, the vertebral body is accessed extrapedicularly or parapedicularly (e.g., without traversing through a pedicle or traversing adjacent to a pedicle). In some implementations, the vertebral body is accessed using an extreme lateral approach or a transforaminal approach, such as used in XLIF and TLIF interbody fusion procedures. In some implementations, an anterior approach is used to access the vertebral body.
In some implementations, the vertebral body may be accessed transforaminally through a basivertebral foramen. Transforaminal access via the spinal canal may involve insertion of a “nerve finder” or nerve locator device and/or imaging/diagnostic tool to avoid damaging spinal cord nerves upon entry by the access tools or treatment devices. The nerve locator device may comprise a hand-held stimulation system such as the Checkpoint Stimulator and Locator provided by Checkpoint Surgical® or the EZstim® peripheral nerve stimulator/nerve locators provided by Avanos Medical, Inc. The nerve finder or nerve locator device could advantageously identify sensitive nerves that should be avoided by the access tools so as not to risk paralysis or spinal cord injury upon accessing the target treatment site. The nerve locator device may be configured to apply stimulation signals between two points or locations and then assess response to determine presence of nerves in the area between the two points or locations. The nerve locator device may include a bipolar pair of stimulation electrodes or monopolar electrodes. In some implementations, the nerve locator features may be implemented on the access tools or treatment devices themselves as opposed to a separate stand-alone device.
Access tools may include an introducer assembly including an outer cannula and a sharpened stylet, an inner cannula configured to be introduced through the outer cannula, and/or one or more additional stylets, curettes, or drills to facilitate access to an intraosseous location within a vertebral body or other bone. The access tools (e.g., outer cannula, inner cannula, stylets, curettes, drills) may have pre-curved distal end portions or may be actively steerable or curveable. Any of the access tools may have beveled or otherwise sharp tips or they may have blunt or rounded, atraumatic distal tips. Curved drills may be used to facilitate formation of curved access paths within bone. Any of the access tools may be advanced over a guidewire in some implementations.
In some implementations, an outer cannula assembly (e.g., introducer assembly) includes a straight outer cannula and a straight stylet configured to be received within the outer cannula. The outer cannula assembly may be inserted first to penetrate an outer cortical shell of a bone and provide a conduit for further access tools to the inner cancellous bone. An inner cannula assembly may include a cannula having a pre-curved or steerable distal end portion and a stylet having a corresponding pre-curved or steerable distal end portion. Multiple stylets having distal end portions with different curvatures may be provided in a kit and selected from by a clinician. The inner cannula assembly may alternatively be configured to remain straight and non-curved.
With reference to
The access tools of
However the curved distal end portions of the curved cannula 212 and the J-stylet 214 and the at least the distal end portion of the straight stylet 314 may be made of flexible and resilient materials. 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 embodiment, the flexible and resilient portions can be made of certain metallic alloys, e.g., nitinol. 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., polyethylene-based 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 using semi-rigid materials. Further, chevron designs or patterns, or through-thickness slits or holes can be applied to make a rigid portion more flexible.
The access tools may be provided as a kit that may include one or more additional introducer cannulas 112, one or more additional introducer stylets 114 (e.g., with different tips, such as one with a bevel tip and one with a diamond or trocar tip), one or more additional curved cannulas 212 (e.g., having a curved distal end portion of a different curvature than a first curved cannula), an one or more additional J-stylets 214 (e.g., having a different curvature or different design configured to access different hardness of bone), an introducer drill 440, and/or an additional straight stylet 314 (e.g., having a different length from the first straight stylet). Some kits may include add-on components or accessory kit modules for accessing hard bone (e.g., the introducer drill 440 and J-stylet 214 specially configured to access hard bone). Some kits may include additional access tool components or accessory kit modules adapted to access one or more additional vertebrae in the same spinal segment or in different spinal segments. The kit may also include one or more (e.g., at least two) treatment devices (such as radiofrequency energy delivery probes).
In some embodiments, the access tools (e.g., kit) may be specifically designed and adapted to facilitate access to hard, non-osteoporotic bone (e.g., bone surrounding or within a vertebral body, such as a cervical vertebra, a thoracic vertebra, a lumbar vertebra, or a sacral vertebra). Hard bone may be determined based on bone mass density testing, compressive strength determinations, compressive modulus determinations, imaging modalities, or based on tactile feel by an operator as access instruments are being advanced. In some implementations, hard bone may be determined as bone having a bone mineral density score within a standard deviation of a normal healthy young adult (e.g., a T score greater than or equal to −1). In some implementations, hard bone may be identified as bone having a compressive strength of greater than 4 MPa and/or a compressive modulus of greater than 80 MPa for cancellous bone. For cortical bone, the compressive strength may be greater than 5.5 MPa and a compressive modulus may be greater than 170 MPa.
The proximal handle 116 includes an upper central opening 120 configured to facilitate straight axial insertion of an introducer stylet 114 or other straight access tool. The upper central opening 120 may be positioned so as to correspond with (e.g., be coaxial with) a central lumen 137 extending through the hypotube 118 of the introducer cannula 112 so as to facilitate insertion of straight instruments (e.g., the introducer stylet 114 or steerable cannulas or steerable stylets) therethrough. The proximal handle 116 may also include coupling features 121 (e.g., recesses, notches, grooves, tabs) to facilitate coupling or mating of a proximal handle 216 of the introducer stylet 114 with the proximal handle 116 of the introducer cannula 112. The coupling features 121 may be adapted to prevent rotation of the introducer stylet 114 and/or to provide assurance that a distal tip 125 of the introducer stylet 114 extends beyond an open distal tip 122 of the hypotube 118 of the introducer cannula 112. As such, penetration of the distal tip 125 of the introducer stylet 114 is facilitated through bone. The upper surface of the proximal handle 116 of the introducer cannula 112 also includes a curved lateral slot 117 and curved ramp 141 to facilitate insertion of the curved cannula assembly 210 into the proximal handle 116 and then into and along the central lumen of the hypotube 118, as will be further described subsequently.
The central lumen 137 of the hypotube 118 extends from the proximal handle 116 to the open distal tip 122 of the hypotube 118. The hypotube 118 may be flared or tapered such that the diameter of the hypotube 118 is not constant along its entire length. For example, the diameter may decrease abruptly at a certain distance (e.g., 1 cm-3 cm) from a lower edge of the lower flange 113 of the proximal handle 116, forming an abrupt narrowing edge 119, and then continue with a constant diameter distally. In another embodiment, the diameter may decrease gradually (e.g., taper uniformly) along the length of the hypotube 118 from the lower edge of the lower flange 113 or the edge 119 to the open distal tip 122 of the hypotube 118. The central lumen 137 of the hypotube 118 may be coated with a medical grade silicone lubricant to improve tool insertion and removal. The outer diameter of the hypotube 118 may range from about 4.2 mm to about 4.5 mm, e.g., from 3 mm to 5 mm. As shown in
The proximal handle 126 of the introducer stylet 114 includes an alignment indicator 129, an anti-rotation tab 131, and a press button 134. As shown best in
The press button 134 is integrally coupled to the anti-rotation tab 131 such that pressing of the press button 134 extends the anti-rotation tab 131 out of the constraint of the slot 117, thereby allowing the introducer stylet 114 to rotate with respect to the introducer cannula 112 (as shown in
In the illustrated example, the gear wheel 221 comprises internal threads configured to interface with corresponding external threads of the threaded proximal shaft portion 220 such that rotation of the gear wheel 221 causes controlled proximal or distal translation of the gear wheel 221 along the threaded proximal shaft portion 220. The threaded proximal shaft portion 220 is sized such that when the gear wheel 221 is in its distal-most position, the distal tip 222 of the curved cannula 212 does not extend out of the open distal tip 122 of the introducer cannula 112 when the curved cannula assembly 210 is fully inserted therein. The gear wheel 221 may spin freely about the threaded proximal shaft portion 220. The threads may comprise triple threads. The gear wheel 221 may be configured to traverse the entire length of the threaded proximal shaft portion 220 with four complete rotations of the gear wheel 221.
The rigid support portion 223 may comprise a biocompatible metal or other rigid material, such as stainless steel, titanium, platinum and/or the like, so as to provide additional support to the curved cannula 212 during insertion of the J-stylet 214. The distal flexible shaft portion 224 may be comprised of a thermoplastic, shape-memory polymer material (such as polyether ether ketone (PEEK), polyurethane, polyethylene terephthalate (PET), and/or the like). The distal end portion 225 may be pre-curved (e.g., shape-set) to have a predetermined curve in a “resting” or unconstrained configuration.
The distal elongate shaft 218 includes a curved distal end portion 227 having an asymmetric curve profile along its length (e.g., the curved distal end portion 227 does not have a constant full diameter along its length). A distal channeling tip 228 is sized and shaped to facilitate channeling through cancellous bone along a curved path or trajectory. The curved distal end portion 227 comprises a flexible curved section 229 having a “D-shaped” cross-sectional profile, as shown, for example, by the cross-sectional profile in
According to several embodiments, the asymmetric curve profile (e.g., profile with D-shaped cross-section) advantageously provides improved cephalad-caudal steering because the curved distal end portion 227 primarily bends inward and not laterally. In addition, the design and material of the curved distal end portion 227 of the J-stylet 214 may enable the angle of curvature of the curved distal end portion 227 to advantageously remain relatively consistent and reproducible across a variety of bone densities, or regardless of bone environment. For example, in one embodiment, the design and material of the curved distal end portion 227 of the J-stylet 214 facilitates consistent and reproducible access to a posterior location (e.g., in a posterior half of the vertebral body or to a location approximately 30%-50% of the distance between the posterior-most aspect and the anterior-most aspect of the vertebral body along a sagittal axis or to a geometric center or midpoint within the vertebral body for vertebral bodies having varying bone densities or other desired target location in the vertebral body or other bone). In accordance with several embodiments, the curvature is designed to deviate by less than 25 degrees (e.g., less than 20 degrees, less than 15 degrees, less than 10 degrees) or less than 30% from the predefined set curvature of the curved distal end portion 227 in an unconstrained configuration (even in hard bone, such as non-osteopenic or non-osteoporotic bone).
Various embodiments of the curved sections 229 may exist for improved performance during an operation and/or for easier removal of the J-stylet 214 from the curved cannula 212, as will be further described subsequently.
The J-stylet 214 may be designed and adapted to exert a lateral force of between 6 pounds and 8 pounds. The curvature of the curved section 229 of the curved distal end portion 227 may result in an angle between the central longitudinal axis of the straight proximal portion of the distal elongate shaft 218 and an axis of the distal channeling tip 228 in a normally unconstrained state. This angle may be between 65 degrees and 80 degrees (e.g., 65 degrees, 70 degrees, 75 degrees, 80 degrees, or any other value within the recited range). The radius of curvature of the curved section 229 may range from 11.5 mm to 15 mm (e.g., from 11.5 mm to 12 mm, from 12 mm to 12.5 mm, from 12 mm to 13 mm, from 12.5 mm to 14 mm, from 13 mm to 14 mm, from 13.5 mm to 15 mm, overlapping ranges thereof, or any value within the recited ranges). The J-stylet 214 may comprise nitinol, other flexible metallic alloy material, for plastic material.
Referring to
The open flute volume of the fluted distal portion 449 may be advantageously configured to hold all or substantially all (e.g., more than 75%, more than 80%, more than 85%, more than 90%) of the significantly-sized bone chips or fragments removed by the introducer drill 440 as the introducer drill 440 is removed from the introducer cannula 112, thereby reducing the bone fragments left behind in the bone (e.g., vertebral body) or in the introducer cannula 112. In some embodiments, the open flute volume of the fluted distal portion 449 is adapted to hold about 2 ccs of bone. The fluted distal portion 449 may exhibit web tapering (e.g., increase in width or depth, or angle with respect to longitudinal axis of the flutes) along its length from distal to proximal (e.g., reverse taper). There may be no web taper for approximately the first 25 mm at the distal-most region. The web taper may then increase gradually until a maximum web taper is reached near the proximal end of the fluted distal portion 449 so as to facilitate pushing of the bone fragments or chip upward (or proximally) along the fluted distal portion 449. For example, the fluted distal portion 449 may have a negative draft (e.g., about 0.77 inch or 20 mm negative draft).
Retraction of the J-Stylet from the Introducer System
In low density bone, retraction of the curved stylet (e.g., J-stylet) 214 may be more difficult than in denser bone due to reduced cancellous bone support of the curved cannula 212. Less curved cannula support at the introducer cannula 112 exit can allow localized lateral deflection of the curved cannula 212 during removal of the curved stylet 214. This causes the introducer cannula exit to have greater interaction with the inner radius of the curved distal end portion 227 of the curved stylet 214 (through the curved cannula wall) as the stylet 214 is pulled into the introducer cannula 112 during removal. Transitions along the curved section inner radius can cause increased resistance during removal of the stylet 214. Therefore, increased flexibility of the curved distal end portion 227 and changes to the transition from the curved section to the distal channeling tip 228 can reduce this stylet/introducer system interaction to lower the stylet removal force.
Design improvements to the stylet 214 allowing for easier removal from the introducer cannula 112 while maintaining its primary function to form a curved path within the bone may include a thinner curved distal end portion 227, a tapered curved distal end portion 227, alternate asymmetric cross-section circumference profiles (e.g. a rectangle, a reverse “D” shape) of the curved distal end portion 227, flatter transitions from the curved distal end portion 227 to the distal channeling tip 228, a curved distal end portion 227 with a full cross-section circumference profile and multiple relief slots, a slot at the distal channeling tip 228 and localized material relief placed proximal to the distal channeling tip 228.
High density bone can reduce lateral deployment. While the lateral deployment force of the curved stylet 214 can be increased in many ways, it may also cause operator difficulty with curved cannula assembly insertion into the introducer cannula 112 and with removal of the stylet 214 from the introducer cannula 112.
At a certain point during a procedure, it may be necessary to remove the J-stylet 214 from the introducer cannula 112 (e.g., from the curved cannula 212 which is inserted within the introducer cannula 112) so as to allow a further instrument (e.g., a radiofrequency treatment probe or straight stylet or drill) to be inserted through the curved cannula 212. For example, when the distal channeling tip 228 has successfully reached a target treatment region within bone, the J-stylet 214 may be removed from the curved cannula 212. After that, a treatment device (e.g., a radiofrequency probe) may be inserted into the curved cannula 212 to conduct tissue modulation. As stated above, the retraction of the J-stylet 214 from the curved cannula 212 may cause interference between the curved distal end portion 227 of the J-stylet 214 and the central lumen 237 of the curved cannula 212. This interaction may result in significant resistance that impedes the retraction, thereby making it more cumbersome for an operator to remove the J-stylet 214.
As shown in
For example, in lower density bone (e.g., osteoporotic bone or osteopenic bone), retraction of the J-stylet 214 may be more difficult than in higher density bone (e.g., non-osteoporotic bone or non-osteopenic bone) due to reduced cancellous bone support of the curved cannula 212. The stronger support of more dense bone may help maintain the shape of the curved cannula 212 so that the central lumen 237 is not as easy to deform.
In some embodiments, the curved distal end portion 227 of the J-stylet 214 can be adjusted or altered to facilitate easier, less cumbersome removal of the J-stylet 214 from the curved cannula 212 or the introducer cannula 112 (e.g., due to decreased friction resistance and/or deformation). As illustrated in
In addition or as an alternative to varying the thickness 234, the material of the distal elongate shaft 218, including the curved distal end portion 227, can be selected to adjust the flexibility of the curved distal end portion 227. A more flexible material may satisfy the requirement of a more flexible curved distal end portion 227. The thickness 234 may be adjusted together with the selection of the material to achieve an optimal flexibility of the curved distal end portion 227. In general, a more flexible curved distal end portion 227 may advantageously more easily conform to the straightening action when the J-stylet 214 is pulled and the curved distal end portion 227 is retracted from the curved distal end 225 of the curved cannula 212 toward the proximal straight portion of the curved cannula 212. As such, less frictional resistance cause by the J-stylet 214 can be achieved.
On the other hand, however, if the curved distal end portion 227 of the J-stylet 214 is made too flexible, it may not be stiff enough to penetrate into hard or cancellous bone when the J-stylet 214 is malleted or otherwise advanced to access bone. In some implementations, there may be need to include different J-stylets 214 with different flexibilities of the curved distal end portions 227 configured for different bone hardness or density.
In some implementations, such as shown in
Referring to
In other configurations, the tapering of the flexible curved section 229 may be reversed from what is illustrated in
In some embodiments, material may be removed from a local part of the flexible curved section 229 for increased local flexibility. In
In some embodiments, the distal channeling tip 228 can be constructed to be more adaptable to shape deformation of the internal surface of the central lumen 237 of the curved cannula 212. Referring to
In some embodiments, the flexible extension 246 in
As shown in
Improvements to the curved cannula 212 allow for greater curvature of the curved cannula assembly when exiting the introducer cannula 112 into bone. Changes to the curved cannula 212 may include chamfering the tip to form a beveled face to deflect the curved cannula 212 laterally. Referring to
In accordance with several embodiments, the method may optionally include removing the introducer stylet after initial penetration into the pedicle 502 (for example, if the operator can tell that the density of the bone is going to be sufficiently dense or hard that additional steps and/or tools will be needed to obtain a desired curved trajectory to access a posterior portion (e.g., posterior half) of the vertebral body 500. With reference to
The curved cannula assembly 210 may then be inserted within the introducer cannula 112 with the gear wheel 221 in the distal-most position so as to prevent inadvertent advancement of the curved cannula assembly 210 out of the open distal tip 122 of the introducer cannula 112 prematurely. With reference to
With reference to
With reference to
At certain levels of the spine (e.g., sacral and lumbar levels) and for certain patient spinal anatomies that require a steeper curve to access a desired target treatment location within the vertebral body, a combination curette/curved introducer may first be inserted to start a curved trajectory (e.g., create an initial curve or shelf) into the vertebra. The curette may have a pre-curved distal end portion or be configured such that the distal end portion can be controllably articulated or curved (e.g., manually by a pull wire or rotation of a handle member coupled to one or more pull wires coupled to the distal end portion or automatically by a robotic or artificial intelligence driven navigation system). The combination curette/curved introducer may then be removed and the outer straight cannula and inner curved cannula/curved stylet assembly may then be inserted to continue the curve toward the target treatment location.
In accordance with several implementations, any of the access tools (e.g., cannula or stylet) or treatment devices may comprise a rheological and/or magnetizable material (e.g., magnetorheological fluid) along a distal end portion of the access tool that is configured to be curved in situ after insertion to a desired location within bone (e.g., vertebra). A magnetic field may be applied to the distal end portion of the access tool and/or treatment device with the magnetizable fluid or other material and adjusted or varied using one or more permanent magnets or electromagnets to cause the distal end portion of the access tool and/or treatment device to curve toward the magnetic field. In some implementations, a treatment probe may include a magnetic wire along a portion of its length (e.g., a distal end portion). Voltage applied to the magnetic wire may be increased or decreased to increase or decrease a curve of the magnetic wire. These implementations may advantageously facilitate controlled steering without manual pull wires or other mechanical mechanisms. The voltage may be applied by instruments controlled and manipulated by an automated robotic control system.
The treatment devices (e.g., treatment probes) may be any device capable of modulating tissue (e.g., nerves, tumors, bone tissue). Any energy delivery device capable of delivering energy can be used (e.g., RF energy delivery devices, microwave energy delivery devices, laser devices, infrared energy devices, other electromagnetic energy delivery devices, ultrasound energy delivery devices, and the like). The treatment device 501 may be an RF energy delivery device. The RF energy delivery device may include a bipolar pair of electrodes at a distal end portion of the device. The bipolar pair of electrodes may include an active tip electrode and a return ring electrode spaced apart from the active tip electrode. The RF energy delivery device may include one or more temperature sensors (e.g., thermocouples, thermistors) positioned on an external surface of, or embedded within, a shaft of the energy delivery device. The RF energy delivery device may not employ internally circulating cooling, in accordance with several implementations.
In some implementations, water jet cutting devices may be used to modulate (e.g., denervate) nerves. For example, a water jet cutter may be configured to generate a very fine cutting stream formed by a very high-pressure jet of water. For example, the pressure may be in the range of 15 MPa to 500 MPa (e.g., 15 MPa to 50 MPa, 30 MPa-60 MPa, 50 MPa-100 MPa, 60 MPa-120 MPa, 100 MPa-200 MPa, 150 MPa-300 MPa, 300 MPa-500 MPa, overlapping ranges thereof, or any value within the recited ranges). In some implementations, a chemical neuromodulation tool injected into a vertebral body or at an endplate may be used to ablate or otherwise modulate nerves or other tissue. For example, the chemical neuromodulation tool may be configured to selectively bind to a nerve or endplate. In some implementations, a local anesthetic (e.g., liposomal local anesthetic) may be used inside or outside a vertebral body or other bone to denervate or block nerves. In some implementations, brachytherapy may be used to place radioactive material or implants within the vertebral body to deliver radiation therapy sufficient to ablate or otherwise denervate the vertebral body. In some implementations, chymopapain injections and/or condoliase injections may be used (e.g., under local anesthesia). Phototherapy may be used to ablate or otherwise modulate nerves after a chemical or targeting agent is bound to specific nerves or to a vertebral endplate.
In accordance with several implementations, thermal energy may be applied within a cancellous bone portion (e.g., by one or more radiofrequency (RF) energy delivery instruments coupled to one or more RF generators) of a vertebral body. The thermal energy may be conducted by heat transfer to the surrounding cancellous bone, thereby heating up the cancellous bone portion. In accordance with several implementations, the thermal energy is applied within a specific frequency range and having a sufficient 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 modulated. In several implementations, modulation comprises permanent ablation or denervation or cellular poration (e.g., electroporation). In some implementations, modulation comprises temporary denervation or inhibition. In some implementations, modulation comprises stimulation or denervation without necrosis of tissue.
For thermal energy, temperatures of the thermal energy may range from about 70 to about 115 degrees Celsius (e.g., from about 70 to about 90 degrees Celsius, from about 75 to about 90 degrees Celsius, from about 83 to about 87 degrees Celsius, from about 80 to about 100 degrees Celsius, from about 85 to about 95 degrees Celsius, from about 90 to about 110 degrees Celsius, from about 95 to about 115 degrees Celsius, or overlapping ranges thereof). The temperature ramp may range from 0.1-5 degrees Celsius/second (e.g., 0.1-1.0 degrees Celsius/second, 0.25 to 2.5 degrees Celsius/second, 0.5-2.0 degrees Celsius/second, 1.0-3.0 degrees Celsius/second, 1.5-4.0 degree Celsius/second, 2.0-5.0 degrees Celsius/second). The time of treatment may range from about 10 seconds to about 1 hour (e.g., from 10 seconds to 1 minute, 1 minute to 5 minutes, from 5 minutes to 10 minutes, from 5 minutes to 20 minutes, from 8 minutes to 15 minutes, from 10 minutes to 20 minutes, from 15 minutes to 30 minutes, from 20 minutes to 40 minutes, from 30 minutes to 1 hour, from 45 minutes to 1 hour, or overlapping ranges thereof). Pulsed energy may be delivered as an alternative to or in sequence with continuous energy. For radiofrequency energy, the energy applied may range from 350 kHz to 650 kHz (e.g., from 400 kHz to 600 kHz, from 350 kHz to 500 kHz, from 450 kHz to 550 kHz, from 500 kHz to 650 kHz, overlapping ranges thereof, or any value within the recited ranges, such as 450 kHz±5 kHz, 475 kHz±5 kHz, 487 kHz±5 kHz). A power of the radiofrequency energy may range from 5 W to 30 W (e.g., from 5 W to 15 W, from 5 W to 20 W, from 8 W to 12 W, from 10 W to 25 W, from 15 W to 25 W, from 20 W to 30 W, from 8 W to 24 W, and overlapping ranges thereof, or any value within the recited ranges). In accordance with several implementations, a thermal treatment dose (e.g., using a cumulative equivalent minutes (CEM) 43 degrees Celsius thermal dose calculation metric model) is between 200 and 300 CEM (e.g., between 200 and 240 CEM, between 230 CEM and 260 CEM, between 240 CEM and 280 CEM, between 235 CEM and 245 CEM, between 260 CEM and 300 CEM) or greater than a predetermined threshold (e.g., greater than 240 CEM). The CEM number may represent an average thermal cumulative dose value at a target treatment region or location and may represent a number that expresses a desired dose for a specific biological end point. Thermal damage may occur through necrosis or apoptosis.
Cooling may optionally be provided to prevent surrounding tissues from being heated during the nerve modulation procedure. The cooling fluid may be internally circulated through the delivery device from and to a fluid reservoir in a closed circuit manner (e.g., using an inflow lumen and an outflow lumen). The cooling fluid may comprise pure water or a saline solution having a temperature sufficient to cool electrodes (e.g., 2-10 degrees Celsius, 5-10 degrees Celsius, 5-15 degrees Celsius). Cooling may be provided by the same instrument used to deliver thermal energy (e.g., heat) or a separate instrument. In accordance with several implementations, cooling is not used.
In some implementations, ablative cooling may be applied to the nerves or bone tissue instead of heat (e.g., for cryoneurolysis or cryoablation applications). The temperature and duration of the cooling may be sufficient to modulate intraosseous nerves (e.g., ablation, or localized freezing, due to excessive cooling). The cold temperatures may destroy the myelin coating or sheath surrounding the nerves. The cold temperatures may also advantageously reduce the sensation of pain. The cooling may be delivered using a hollow needle under fluoroscopy or other imaging modality.
In some implementations, one or more fluids or agents may be delivered to a target treatment site to modulate a nerve. The agents may comprise bone morphogenetic proteins, for example. In some implementations, the fluids or agents may comprise chemicals for modulating nerves (e.g., chemoablative agents, alcohols, phenols, nerve-inhibiting agents, or nerve stimulating agents). The fluids or agents may be delivered using a hollow needle or injection device under fluoroscopy or other imaging modality.
One or more treatment devices (e.g., probes) may be used simultaneously or sequentially. For example, the distal end portions of two treatment devices may be inserted to different locations within a vertebral body or other bone or within different vertebral bodies or bones. Radiofrequency treatment probes may include multiple electrodes configured to act as monopolar, or unipolar, electrodes or as pairs of bipolar electrodes. The treatment device(s) may also be pre-curved or curveable such that the curved stylet is not needed or may have sharp distal tips such that additional sharpened stylets are not needed. In some implementations, any or all of the access tools and the treatment devices are MR-compatible so as to be visualized under MR imaging.
The one or more treatment devices (e.g., probes such as radiofrequency probes, treatment device 501 of a kit or system) may include an indicator configured to alert a clinician as to 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. The light ring may be configured to light up with different colors and/or exhibit other visible effects (e.g., pulsing on and off with certain patterns). The one or more treatment devices may also be configured to provide audible alerts (e.g., beeps having a certain frequency or intonation) corresponding to different operational states. In one implementation, the light ring may be dark or not lit up when the treatment device is not connected to a radiofrequency generator or not ready for RF energy delivery. The light ring may pulse at a first rate (e.g., 1 pulse every 2-3 seconds) to indicate an operational state in which the treatment device and generator system are ready to initiate RF energy delivery. The light ring may be continuously lit up to indicate an operational state in which the treatment device is actively delivering RF energy. The light ring may pulse at a second rate different than (e.g., faster than, slower than) the first rate to indicate an operational state in which an error has been detected by the generator or if a particular treatment parameter is determined to be outside an acceptable range of values. In one implementation, the second rate is greater than the first rate (e.g., 2 pulses per second). Haptic feedback may also be provided to the clinician for at least some of the operational states to provide a further alert in addition to a visible alert.
In some implementations, the treatment device (e.g., treatment device 501) includes a microchip that is pre-programmed with treatment parameters (e.g., duration of treatment, target temperature, temperature ramp rate). Upon electrical connection of the treatment device to the generator, the treatment parameters are transmitted to the generator and displayed on a display of the generator to provide confirmation of desired treatment to a clinician.
The generator 400 also includes a display 408 configured to display information to the clinician or operator. During startup and use, the current status of the generator 400 and energy delivery (treatment) parameters may be displayed on the display 408. During energy delivery, the display 408 may be configured to display remaining treatment time, temperature, impedance, and power information (alphanumerically and/or graphically). For example, graphical representations of power vs. time and impedance vs. time may be displayed. In one implementation, the display may comprise a color, active matrix display. The generator 400 further includes a start/pause button 410 configured to be pressed by an operator to initiate and stop energy delivery. Similar to the indicator light 406 surrounding the instrument connection port 405, a second indicator light 412 may surround the start/pause button 410. The second indicator light 412 may also comprise a circular LED indicator light. The second indicator light 412 may be configured to continuously illuminate in a solid color (e.g., white, blue, green) when the generator 400 is powered on and ready to initiate energy delivery. The indicator light 412 may flash at a first pulsing rate (e.g., 1 Hz) to prompt a clinician to press the start/pause button 410 to initiate energy delivery. The indicator light 412 may flash at a second pulsing rate different than (e.g., faster than) the first pulsing rate (e.g., 2 Hz, 3 Hz, 4 Hz) when energy delivery has been paused or stopped. The generator 400 may also be configured to output audible alerts indicative of the different operating conditions (e.g., to coincide with the output of the indicator lights 406, 412.
The generator 400 may also include a power button 414 configured to power on and off the generator 400, a standby power indicator light 416 configured to illuminate (e.g., in solid green color) when an AC power switch (not shown) of the generator 400 is switched on, an RF active indicator light 417 configured to illuminate (e.g., in solid blue color) during RF energy delivery, and a system fault indicator light 418 configured to illuminate (e.g., in solid red color) during a system fault condition. The generator 400 may also include user input buttons 420 configured to facilitate navigation and selection of options (e.g., menu options, configuration options, acknowledgement requests) that appear on the display 408 (e.g., arrow buttons to toggle up and down between options and an “enter” button for user selection of a desired option).
For access to locations outside bone (e.g., extraosseous locations, such as outside a vertebral body), visualization or imaging modalities and techniques may be used to facilitate targeting. For example, a foramen of a vertebral body (e.g., basivertebral foramen) may be located using MRI guidance provided by an external MR imaging system, CT guidance provided by an external tomography imaging system, fluoroscopic guidance using an external X-ray imaging system, and/or an endoscope inserted laparoscopically. Once the foramen is located, therapy (e.g., heat or energy delivery, chemoablative agent delivery, cryotherapy, brachytherapy, and/or mechanical severing) may be applied to the foramen sufficient to modulate (e.g., ablate, denervate, stimulate) any nerves entering through the foramen. For example, an endoscope may be used to locate the foramen under direct visualization and then the basivertebral nerve may be mechanically transected near the foramen. In some implementations, an intervertebral disc and vertebral body may be denervated by treating (e.g., ablating) a sinuvertebral nerve prior to the sinuvertebral nerve branching into the basivertebral nerve that enters the basivertebral foramen of the vertebral body. Because vertebral endplates are cartilaginous, radiation or high-intensity focused ultrasound energy may be applied to vertebral endplates from a location external to a subject's body altogether to denervate nerves in the vertebral endplates.
In accordance with several implementations, target, or candidate, vertebrae for treatment can be identified prior to treatment. The target, or candidate, vertebrae may be identified based on identification of various types of, or factors associated with, endplate degeneration and/or defects (e.g., focal defects, erosive defects, rim defects, corner defects, all of which may be considered pre-Modic change characteristics). For example, one or more imaging modalities (e.g., MRI, 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 that include findings of inflammation and edema or type 2 Modic changes that include changes in bone marrow (e.g., fibrosis) and increased visceral fat content). For example, images obtained via MRI (e.g., IDEAL 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 1 Modic change. Examples of pre-Modic change characteristics could include mechanical characteristics (e.g., loss of soft nuclear material in an adjacent intervertebral disc of the vertebral body, reduced disc height, reduced hydrostatic pressure, microfractures, focal endplate defects, erosive endplate defects, rim endplate defects, corner endplate defects, osteitis, spondylodiscitis, Schmorl's nodes) or bacterial characteristics (e.g., detection of bacteria that have entered an intervertebral disc adjacent to a vertebral body, a disc herniation or annulus tear which may have allowed bacteria to enter the intervertebral disc, inflammation or new capilarisation that may be caused by bacteria) or other pathogenetic mechanisms that provide initial indications or precursors of potential Modic changes or vertebral endplate degeneration or defects.
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. Modic changes may or may not be correlated with endplate defects and may or may not be used in candidate selection or screening. In accordance with several embodiments, Modic changes are not evaluated and only vertebral endplate degeneration and/or defects (e.g., pre-Modic change characteristics prior to onset or prior to the ability to identify Modic changes) are identified. Rostral and/or caudal endplates may be evaluated for pre-Modic changes (e.g., endplate defects that manifest before Modic changes that may affect subchondral and vertebral bone marrow adjacent to a vertebral body endplate).
In some implementations, a level of biomarker(s) (e.g., substance P, cytokines, high-sensitivity C-reactive protein, or other compounds associated with inflammatory processes and/or pain and/or that correlate with pathophysiological processes associated with vertebral endplate degeneration or defects (e.g., pre-Modic changes) or Modic changes such as disc resorption, Type III and Type IV collagen degradation and formation, or bone marrow fibrosis) may be obtained from a patient (e.g., through a blood draw (e.g., blood serum) or through a sample of cerebrospinal fluid) to determine whether the patient is a candidate for basivertebral nerve ablation treatment (e.g., whether they have one or more candidate vertebral bodies exhibiting factors or symptoms associated with endplate degeneration or defects (e.g., pre-Modic change characteristics)). Cytokine biomarker samples (e.g., pro-angiogenic serum cytokines such as vascular endothelial growth factor (VEGF)-C, VEGF-D, tyrosine-protein kinase receptor 2, VEGF receptor 1, intercellular adhesion molecule 1, vascular cell adhesion molecule 1) 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, such as neo-epitopes of type III and type IV pro-collagen (e.g., PRO-C3, PRO-C4) and type III and type IV collagen degradation neo-epitopes (e.g., C3M, C4M).
In some implementations, samples are obtained over a period of time and compared to determine changes in levels overtime. 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 endplate degeneration or defects (e.g., pre-Modic change characteristics) or Modic changes, as described above), treatment may be recommended and performed to prevent or treat back pain. Biomarker levels (e.g., substance P, cytokine protein levels, PRO-C3, PRO-C4, C3M, C4M 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.
The identification of pre-Modic change characteristics may involve determining a quantitative or qualitative endplate score based on severity, extent, and/or quantity of the identified pre-Modic change characteristics (e.g., vertebral endplate defects) and vertebrae having a quantitative endplate score above a threshold may be deemed as potential candidates for treatment (e.g., basivertebral nerve ablation). The pre-Modic change characteristics may be combined with age, gender, body mass index, bone mineral density measurements, back pain history, and/or other known risk factors for vertebral endplate degeneration or defects (such as smoking, occupational or recreational physical demands or situations) in identifying candidate patients and/or candidate vertebral bodies for treatment (e.g., basivertebral nerve ablation).
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 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.
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.
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.
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 disclosed herein 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 applying of thermal energy.”
The terms “top,” “bottom,” “first,” “second,” “upper,” “lower,” “height,” “width,” “length,” “end,” “side,” “horizontal,” “vertical,” and similar terms may be used herein; it should be understood that these terms have reference only to the structures shown in the figures and are utilized only to facilitate describing embodiments of the disclosure. The terms “proximal” and “distal” are opposite directional terms. For example, the distal end of a device or component is the end of the component that is furthest from the operator during ordinary use. A distal end or tip does not necessarily mean an extreme distal terminus. The proximal end refers to the opposite end, or the end nearest the operator during ordinary use. 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 2:1” includes “2:1.” 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.
The present application claims priority to U.S. Provisional Patent Application No. 63/507,982, filed Jun. 13, 2023, the entire disclosure of which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63507982 | Jun 2023 | US |
