Sacral nerve stimulation lead alignment features and associated systems and methods

Abstract

Systems and methods for implanting sacral nerve stimulation leads through a target sacral foramen and proximate a target sacral nerve are disclosed. For example, an alignment system including a primary alignment feature and a secondary alignment feature couplable to the primary alignment feature are provided. The primary alignment feature lies flat against the patient's skin and includes radiopaque grid lines that form a coordinate system on the patient's skin. An imaging device obtains a first image that includes both the primary alignment feature and the target foramen. The position of the target foramen is correlated to a position on the primary alignment feature based on the first image. The secondary alignment feature is coupled to the primary alignment feature and provides an indication of the specific insertion point and insertion angle for a delivery instrument carrying a signal delivery device into the patient.

Description

Attorney Docket No.: 143662.8009. WO00SACRAL NERVE STIMULATION LEAD ALIGNMENT FEATURES AND ASSOCIATED SYSTEMS AND METHODSCROSS-REFERENCE TO RELATED APPLICATION(S)

[0001] The present application claims priority to U.S. Provisional Patent Application No. 63 / 690,271 , filed September 3, 2024, the disclosure of which is incorporated by reference herein in its entirety.TECHNICAL FIELD

[0002] The present technology is directed toward electrically modulating nervous tissue to treat a patient condition.BACKGROUND

[0003] Neurological stimulation systems generally have a signal generator that generates electrical pulses, and one or more signal delivery devices such as leads that deliver the electrical pulses to neurological tissue or muscle tissue. The delivered electrical pulses modulate neural activity to treat an underlying patient condition. For example, neurostimulation has been used to treat various disorders such as pain, movement disorders, cardiac disorders, and various other medical conditions. Sacral neuromodulation (SNM) is a type of neuromodulation in which electrical stimulation is applied to one or more sacral nerves to treat a patient condition. SNM has been used to treat various urological disorders, including urinary retention, urinary urge incontinence, urgency frequency, and fecal incontinence.BRIEF DESCRIPTION OF THE DRAWINGS

[0004] Figure 1A is a partially schematic illustration of an implantable sacral neuromodulation system positioned at a patient's sacral region to deliver electrical signals in accordance with some embodiments of the present technology.

[0005] Figure 1 B illustrates sacral nerve anatomy of a patient, along with a portion of a signal delivery device of the system of Figure 1A shown as implanted at a representative location in accordance with some embodiments of the present technology.-1-143662.8009. WO00X18295141 .1Attorney Docket No.: 143662.8009. WO00

[0006] Figure 2A is a partially schematic illustration of an electrical signal generated in accordance with some embodiments of the present technology.

[0007] Figure 2B is a partially schematic illustration of another electrical signal generated in accordance with some embodiments of the present technology.

[0008] Figures 3A-3C illustrate various primary alignment features configured in accordance with some embodiments of the present technology.

[0009] Figure 4A is a partially schematic view of the primary alignment feature of Figure 3A positioned on the skin of the patient at the patient's sacral region in accordance with some embodiments of the present technology.

[0010] Figure 4B is a partially schematic view of the primary alignment feature of Figure 3B positioned on the skin of the patient at a patient's sacral region in accordance with some embodiments of the present technology.

[0011] Figures 5A-5D illustrate various secondary alignment features configured in accordance with some embodiments of the present technology.

[0012] Figures 6A and 6B are perspective views of the primary alignment feature of Figure 3B being used in combination with the second alignment feature of Figures 5B-5D in accordance with some embodiments of the present technology.

[0013] Figure 7 is a partially schematic lateral view of the secondary alignment feature of Figures 5B-5D positioned in accordance with some embodiments of the present technology.

[0014] Figure 8 is a flowchart of a method of implanting sacral nerve stimulation leads in accordance with some embodiments of the present technology.DETAILED DESCRIPTIONA. Introduction

[0015] The present technology is directed to systems and methods for implanting sacral nerve stimulation leads through a target sacral foramen and proximate a target sacral nerve to facilitate neurostimulation of the target sacral nerve. For example, the present technology includes an alignment system including a primary alignment feature and a secondary alignment feature that is removably couplable to or positionable on the-2-143662.8009. WO00X18295141 .1Attorney Docket No.: 143662.8009. WO00 primary alignment feature. The primary alignment feature can lie generally flat against the patient's skin and includes radiopaque grid lines that form a visible coordinate system on the patient's skin. The radiopaque grid lines help in accurately correlating internal anatomical landmarks, such as the patient's sacral foramen and associated nerves, with external landmarks (e.g., positions on the surface of the patient's skin) when reviewing fluoroscopic images of the patient. The secondary alignment feature can be coupled to the primary alignment feature based on the correlated position of the target foramen on the primary alignment feature, and provides an indication of the specific insertion point and insertion angle for a delivery instrument (e.g., a needle) carrying a signal delivery device (e.g., a stimulation lead).

[0016] Without intending to be bound by theory, it is expected that the present technology may enhance the accuracy and efficiency of delivering stimulation leads for sacral nerve stimulation by assisting with identifying the location of a target foramen and associated sacral nerve, and guiding the insertion of medical instruments into the patient and toward the nerve. As a result, the present technology may facilitate faster procedure times by reducing the time required to find the correct foramen and place the lead, increasing efficiency of the procedure. Furthermore, the alignment systems and associated methods described herein may reduce medical personal's exposure to radiation by reducing the number of x-rays needed throughout the procedure (e.g., by reducing / eliminating the need to repeatedly take x-rays to incrementally guide placement of the signal delivery device), and / or by removing the need to have medical personnel be near the x-ray beam while capturing images. Additionally, the present technology can provide a source of physical documentation that the delivery instrument (e.g., the needle) and signal delivery device (e.g., the stimulation lead) were properly inserted in the correct foramen.

[0017] The present technology is also expected to be relatively simple to employ, expanding accessibility of the procedure to medical personnel with a broad range of skill and familiarity with the procedure and associated anatomy. For example, many of the alignment systems described herein are expected to be compatible with existing neuromodulation systems, and can therefore be used to assist with the implantation of existing sacral stimulation leads. As one skilled in the art will appreciate, the foregoing advantages are provided by way of example only, and embodiments of the present-3-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 technology may have additional advantages in addition to or in lieu of those expressly identified herein.

[0018] Unless otherwise stated, the terms "generally," "about," and "approximately" refer to values within 10% of a stated value. For example, the use of the term "about 100" refers to a range of 90 to 110, inclusive. In instances in which relative terminology is used in reference to something that does not include a numerical value, the terms are given their ordinary meaning to one skilled in the art.

[0019] As used herein, and unless otherwise noted, the terms "modulate," "modulation," "stimulate," and "stimulation" refer generally to electrical signals that have an inhibitory, excitatory, and / or other effect on a target neural population. Accordingly, a sacral nerve "stimulator" can have an inhibitory effect and / or an excitatory effect on certain neural populations.

[0020] As used herein, the terms "electrical therapy signal," "electrical signal," "therapy signal," "signal," and other associated terms are used interchangeably and generally refer to an electrical signal that can be characterized by one or more parameters, such as frequency, pulse width, and / or amplitude.

[0021] As used herein, "proximate a target neural population" refers to the placement of a signal delivery element such that it can deliver electrical stimulation to the target neural population. For example, if the target population includes the third sacral spinal nerve, "proximate the target neural population" includes, but is not limited to, the relative lead positions described and shown in Figure 1 B, as well as other positions not expressly described herein.

[0022] Specific details of certain embodiments of the disclosure are described below with reference to methods for modulating one or more target neural populations (e.g., nerves) or sites of a patient, and associated implantable structures for providing the modulation. Although selected embodiments are described below with reference to modulating the sacral nerves, the modulation may in some instances be directed to other neurological structures and / or target neural populations and / or other neurological tissues throughout the body. For example, some embodiments may include modulating the vagus nerve, the splenic nerve, the splanchnic nerve, and / or other peripheral nerves. Some embodiments can have configurations, components, and / or procedures different than those described herein, and other embodiments may eliminate particular-4-143662.8009.WO00M 82951419.1Attorney Docket No.: 143662.8009. WO00 components and / or procedures. A person of ordinary skill in the relevant art, therefore, will understand that the present disclosure may include other embodiments with additional elements, and / or may include other embodiments without several of the features shown and described below with reference to Figures 1 A-8.B. Representative Embodiments of Sacral Neuromodulation Systems and Associated Stimulation Waveforms

[0023] Figure 1A schematically illustrates a sacral neuromodulation system 100 ("the system 100") implanted to stimulate a patient's sacral nerves and configured in accordance with embodiments of the present technology. The system 100 includes a signal generator 1 10 and a signal delivery device 120. The signal generator 110 can be implanted and / or implantable subcutaneously within the patient P. For example, in the illustrated embodiment the signal generator 110 is implanted subcutaneously at the lower back / upper buttock area of the patient P (e.g., adjacent but posterior to the iliac crest IC and / or iliac fossa IF).

[0024] The signal delivery device 120 extends from the signal generator 1 10 and can be implanted within the patient P proximate a target neural population. In some embodiments, the target neural population includes one or more of the sacral spinal nerves (e.g., the S1 sacral nerve, the S2 sacral nerve, the S3 sacral nerve and / or the S4 sacral nerve). Accordingly, in some embodiments the signal delivery device 120 can extend through one of the sacral foramen S1 -S4 (the illustrated embodiment depicts the signal delivery device 120 extending through the sacral foramen S1 ) and adjacent one or more sacral spinal nerves when implanted. More specifically, the signal delivery device 120 can be implanted proximate the S1 sacral nerve, the S2 sacral nerve, the S3 sacral nerve, and / or the S4 sacral nerve. The signal delivery device 120 can carry features configured to administer therapy to the target neural population. For example, the signal delivery device 120 can include one or more lead(s) or lead bodies 122 extending from the signal generator 110 toward the target neural population (e.g., toward the S3 sacral nerve). As described in greater detail with reference to Figure 1 B, the lead 122 can include or carry one or more electrical contacts or electrodes (e.g., ring electrodes, cuff electrodes, and / or other suitable electrical contacts) that deliver electrical signals to the target neural population.-5-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00

[0025] In operation, the signal generator 1 10 can generate and transmit signals (e.g., electrical signals) to the signal delivery device 120. In turn, the signal delivery device 120 can deliver the electrical signals to the target neural population, e.g., to electrically modulate neurons within the target neural population to induce a therapeutic effect in the patient. Representative electrical signals that can be generated by the signal generator 1 10 and delivered to the patient P via the signal delivery device 120 are described in greater detail below with reference to Figures 2A and 2B.

[0026] The signal generator 110 can include a machine-readable (e.g., computer- readable) medium containing instructions for generating and transmitting electrical signals. Accordingly, generating electrical signals in accordance with the methods described herein can include executing computer-executable instructions contained by, on, or in computer-readable media located within the signal generator 1 10. The signal generator 110 can also include one or more processors for executing the machine- readable instructions, memory unit(s), batteries (rechargeable and / or non- rechargeable), communication devices (e.g., an antenna), and / or other software or hardware-based components. As shown in Figure 1 A, the signal generator 1 10 can include a single housing for storing some or all of the foregoing components, although in other embodiments some or all of the foregoing components can be stored in separate housings.

[0027] In some embodiments, the signal generator 1 10 can be configured to communicate with one or more external controllers. For example, the signal generator 110 can wirelessly communicate with a physician controller (not shown) that is external to the patient P. A physician or other healthcare provider can use the physician controller to program the signal generator 1 10, e.g., to select parameters for the electrical signal to be generated by the signal generator 110. In some embodiments, the signal generator 1 10 can also communicate with a patient controller that is external to the patient P. The patient P can use the patient controller to control various aspects of the therapy provided by the signal generator 1 10. For example, the patient may be able to start and stop electrical stimulation therapy using the patient controller, and / or control certain parameters (e.g., amplitude) of the electrical stimulation using the patient controller. In some embodiments, the signal generator 1 10 can transmit data to the physician controller and / or the patient controller for user review. For example, the signal generator 110 may periodically (or on demand) transmit data associated with one or-6-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 more of electrode impedance, battery power, program settings (e.g., current signal parameters), historical program settings (e.g., historical signal parameters), program / parameter changes, usage data (e.g., stimulation start and stop times), or the like. The physician controller and the patient controller can include a dedicated controller device, or be implemented as an application on a smartphone, tablet, etc.

[0028] In some embodiments, the system 100 can be implanted in the patient P to treat a gastrointestinal and / or urogenital condition. For example, the system 100 can be implanted to treat IBD or an associated condition, including Crohn's disease or ulcerative colitis. For example, the system 100 can deliver electrical signals to one or more sacral nerves of the patient to electrically stimulate the one or more sacral nerves. As described in detail throughout this Detailed Description, the electrical signal can treat, reduce, and / or ameliorate the IBD. For example, the electrical signal may reduce one or more IBD-related symptoms (e.g., diarrhea, abdominal pain, weight loss, etc.), and / or reduce inflammation causing the one or more symptoms. Moreover, although shown as providing unilateral stimulation, in some embodiments the system 100 can be configured to provide bilateral sacral nerve stimulation to treat the patient's IBD. Additional details of electrical signals and stimulation regimes for treating IBD are described below with reference to Figures 2A and 2B. In some embodiments, the system 100 can be implanted to treat other conditions, such as fecal incontinence, urinary incontinence, urinary retention, or the like.

[0029] In some embodiments, prior to receiving the signal generator 110, the patient P undergoes a trial period during which the patient P receives electrical stimulation to determine whether the patient P responds favorably to stimulation therapy. During the trial period, the patient P may use a temporary, external trial stimulator that generates and transmits electrical signals to the target neural population via the signal delivery device 120 or another implanted signal delivery element. If the patient responds favorably during the trial period, the patient may elect to have the signal generator 1 10 implanted to facilitate chronic stimulation therapy. In some embodiments, the trial period can be omitted, and the signal generator 1 10 can be implanted without the patient previously receiving stimulation from a temporary external signal generator.-7-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00

[0030] Figure 1 B is an illustration of a sacral plexus SP of a patient, along with a distal portion of the lead 122 shown as implanted at a representative location. The sacral plexus SP includes four sacral spinal nerves: the first sacral nerve S1 , the second sacral nerve S2, the third sacral nerve S3, and the fourth sacral nerve S4. The lead 122 is shown as extending along (e.g., proximate to) the third sacral nerve S3 such that it can electrically stimulate the third sacral nerve S3. In other embodiments, however, the lead 122 can be positioned proximate other sacral spinal nerves, and / or proximate other nerve fibers of the sacral plexus SP, to electrically stimulate other target tissue. In yet other embodiments, the lead 122 can be positioned proximate other neural structures of the sacral plexus SP.

[0031] Figure 1 B also shows a plurality of electrodes or electrical contacts 124a- d carried by the lead 122, as described previously. Electrical signals generated by the signal generator 1 10 and transmitted through the lead 122 can be delivered to the target neural population via the electrodes 124a-d. Although shown as having four electrodes, the lead 122 can have more or fewer electrodes, such as one, two, three, four, five, six, seven, eight, or more.

[0032] In some embodiments, test stimulation may be administered to a patient during a procedure to implant the signal delivery device 120. This can be done to ensure adequate placement of the lead 122, e.g., to ensure that the electrical signals delivered via the lead 122 are applied to the target neural population. In some embodiments, test stimulation is administered at or above a sensory threshold during an implant procedure such that the patient can give intraoperative feedback about the location of the sensation, and thus the location of the lead 122. In some embodiments, test stimulation is administered at or above a motor threshold during the implant procedure, and a motor response to the test stimulation is observed to determine the location of the lead 122. In other embodiments, however, placement of the lead 122 can be confirmed using other techniques (e.g., imaging), such that intraoperative test stimulation is not required.

[0033] Figure 2A is a partially schematic illustration of a representative electrical signal waveform 200 ("the signal 200") generated in accordance with embodiments of the present technology. The signal 200 can be generated by the system 100 (e.g., by the signal generator 110) described above with respect to Figures 1A and 1 B, or by another sacral neuromodulation system. As described throughout this Detailed-8-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00Description, the signal 200 can be delivered to a patient's sacral region to treat a patient condition such as IBD.

[0034] The signal 200 includes repeating pulse periods 201 , with each pulse period 201 having a biphasic pulse 202 followed by an interpulse interval 212. Each pulse 202 includes a first pulse phase 203 having a first polarity followed by a second pulse phase 204 having a second polarity that is opposite the first polarity. For example, in the illustrated embodiment the first pulse phase 203 is an anodic pulse phase and the second pulse phase 204 is a cathodic pulse phase, although in other embodiments the anodic pulse phase and the cathodic pulse phase can be reversed, such that the cathodic pulse phase is the first pulse phase and the anodic pulse phase is the second pulse phase. In other embodiments, the signal 200 includes monophasic pulses. In such embodiments, the signal 200 includes repeating pulses of the same polarity.

[0035] In some embodiments, the first pulse phase 203 is separated from the second pulse phase 204 by an interphase interval 208. During the interphase interval 208, the amplitude of the signal 200 can return to baseline (e.g., zero or about zero), although in other embodiments the amplitude of the signal 200 during the interphase interval 208 can be a non-zero value. In some embodiments, the interphase interval 208 is omitted, and the signal 200 transitions directly from the first pulse phase 203 to the second pulse phase 204.

[0036] The first pulse phase 203 can have a pulse width 206 within a pulse width range of from about 100 microseconds to about 2 milliseconds. For example, the first pulse phase 203 can have a pulse width 206 within a pulse width range of from about 100 microseconds to about 1 .5 milliseconds, or from about 100 microseconds to about 1 millisecond, or from about 100 microseconds to about 800 microseconds, or from about 200 microseconds to about 700 microseconds, or from about 200 microseconds to about 600 microseconds, or from about 300 microseconds to about 700 microseconds, or from about 300 microseconds to about 600 microseconds, or from about 300 microseconds to about 500 microseconds, or from about 400 microseconds to about 600 microseconds, or from about 400 microseconds to about 500 microseconds. For example, in some embodiments the pulse width 206 can be about 100 microseconds, about 150 microseconds, about 200 microseconds, about 250 microseconds, about 300 microseconds, about 350 microseconds, about 400-9-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 microseconds, about 450 microseconds, about 500 microseconds, about 550 microseconds, about 600 microseconds, about 650 microseconds, or about 700 microseconds. The foregoing pulse width ranges and values are provided by way of example only — in some embodiments, the electrical signals described herein may have pulse width values outside the foregoing ranges.

[0037] In some embodiments, the second pulse phase 204 has the same or about the same pulse width as the first pulse phase 203. Accordingly, the second pulse phase 204 can have any of the pulse widths recited above with respect to the first pulse phase 203. In other embodiments, however, the second pulse phase 204 can have a different pulse width than the first pulse phase 203. For example, if the first pulse phase 203 has a pulse width of 400 microseconds or less, the second pulse phase 204 may have a pulse width of 600 microseconds or more. Likewise, if the first pulse phase 203 has a pulse width of 600 microseconds or more, the second pulse phase 204 may have a pulse width of 400 microseconds or less. In general, when the second pulse phase 204 has a different pulse width than the first pulse phase 203, the pulse width of the second pulse phase 204 can be 50%, 60%, 70%, 80%, 90%, 1 10%, 120%, 130%, 140%, 150%, 160%, 170%, 180%, 190% or 200% of the pulse width of the first pulse phase 203.

[0038] Regardless of whether the first pulse phase 203 and the second pulse phase 204 have the same pulse width, a total charge delivered during the second pulse phase 204 can be equal or approximately equal in magnitude and opposite in polarity from the total charge delivered during the first pulse phase 203. In this way, the second pulse phase 204 is a charge balancing pulse that prevents or at least reduces charge buildup at the electrode used to deliver the signal 200. Accordingly, in embodiments for which the first pulse phase 203 and the second pulse phase 204 have an equal or approximately equal pulse width, the first pulse phase 203 and the second pulse phase 204 can have an equal or approximately equal and opposite amplitude. In embodiments in which the first pulse phase 203 and the second pulse phase 204 have different pulse widths, the first pulse phase 203 and the second pulse phase 204 can have different amplitudes such that the total charge delivered during the first pulse phase 203 and the second pulse phase 204 remains approximately the same. In other embodiments, the pulse 202 can be charge imbalanced, such that the first pulse phase 203 and the second pulse phase 204 do not deliver charges of the same magnitude. In such embodiments, charge buildup at the electrode may passively dissipate.-10-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00

[0039] The interpulse interval 212 is a quiescent period between sequential pulses 202. During the interpulse interval 212, the signal 200 can return to a baseline amplitude (e.g., zero or about zero) such that little to no charge is administered to the patient. In some embodiments, the interpulse interval can be within an interpulse interval range of from about 1 millisecond to about 1 second, such as from about 5 milliseconds to about 500 milliseconds, or from about 50 milliseconds to about 500 milliseconds, or from about 100 milliseconds to about 300 milliseconds. The foregoing interpulse interval ranges and values are provided by way of example only — in some embodiments, the electrical signals described herein may have interpulse interval values outside the foregoing ranges. In some embodiments, the duration of the interpulse interval 212 can be set independently from the duration of the pulses 202. In other embodiments, the duration of the interpulse interval 212 is set based on a selected pulse 202 duration and desired signal frequency.

[0040] The duration of the pulse period 201 determines the frequency of the signal 200. For example, if the duration of the pulse period 201 is 200 milliseconds, then the frequency of the signal is 5 Hz (i.e., five pulse periods 201 are delivered per second). The signal 200 can have a frequency between about 0.5 Hz and about 130 Hz. For example, the signal 200 can have a frequency within a frequency range of from about 1 Hz to about 40 Hz, or from about 1 Hz to about 30 Hz, or from about 1 Hz to about 25 Hz, or from about 1 Hz to about 20 Hz, or from about 1 Hz to about 15 Hz, or from about 5 Hz to about 15 Hz, or from about 1 Hz to about 12 Hz, or from about 1 Hz to about 10 Hz, or from about 2 Hz to about 8 Hz, or from about 3 Hz to about 7 Hz, or from about 4 Hz to about 6 Hz, or from about 4.5 Hz to about 5.5 Hz, or from about 4.8 Hz to about 5.2 Hz. In other embodiments, the signal 200 can have a frequency of about 0.5 Hz, about 1 Hz, about 2 Hz, about 3 Hz, about 4 Hz, about 5 Hz, about 6 Hz, about 7 Hz, or about 8 Hz. In some embodiments, the signal 200 can have a frequency of about 4.2 Hz, about 4.4 Hz, about 4.6 Hz, about 4.8 Hz, about 5.0 Hz, about 5.2 Hz, about 5.4 Hz, about 5.6 Hz, or about 5.8 Hz. The foregoing frequency ranges and values are provided by way of example only — in some embodiments, the electrical signals described herein may have frequency values outside the foregoing ranges.

[0041] The pulses 202 can have a current amplitude between about 0.1 mA and about 20 mA. For example, in some embodiments the pulses 202 have a current amplitude within a current amplitude range of from about 0.5 mA to about 15 mA, or-11 -143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 from about 1 mA to about 12 mA, or from about 2 mA to about 12 mA, or from about 3 mA to about 10 mA. The pulses 202 can also have a voltage amplitude between about 0.1 V and 15 V. For example, in some embodiments the pulses 202 have a voltage amplitude within a voltage amplitude range of from about 0.1 V to about 10 V, or from about 0.2 V to about 8 V, or from about 0.5 V to about 4 V. In some embodiments, the amplitude (e.g., the current amplitude and / or the voltage amplitude) of the signal 200 is set based on an individual patient's sensory threshold and / or motor threshold. For example, in some embodiments the pulses 202 have a peak amplitude that is below the sensory or perception threshold of the patient. In such embodiments, the patient generally cannot actively feel the signal 200 as it is being administered. For example, the pulses 202 may have an amplitude that is 50% of sensory threshold, 60% of sensory threshold, 70% of sensory threshold, 80% of sensory threshold, 90% of sensory threshold, or 95% of sensory threshold. In other embodiments, the pulses 202 have an amplitude that is at or above the sensory threshold, such that the patient can perceive the signal 200 being delivered. In yet other embodiments, the pulses 202 have an amplitude that is below the motor threshold of the patient. In such embodiments, the signal 200 does not induce clinically discernable movement (e.g., muscle twitching) in the patient while being administered. For example, the pulses 202 may have an amplitude that is 50% of motor threshold, 60% of motor threshold, 70% of motor threshold, 80% of motor threshold, 90% of motor threshold, or 95% of motor threshold.

[0042] In some embodiments, electrical signals generated in accordance with the present technology can have one more ramped parameters. For example, Figure 2B illustrates an electrical signal 250 ("the signal 250") with a ramped amplitude in accordance with some embodiments of the present technology. The signal 250 can be generally similar to the signal 200, and can have any of the parameters and parameter values described above in connection with the signal 200. However, relative to the signal 200, an amplitude of the of the signal 250 can be ramped such that a peak amplitude of the signal 250 changes over time. In the illustrated embodiment, for example, the signal 250 includes a plurality of pulses 252 (five pulses 252a-252e are shown), with each sequential pulse 252 having a different amplitude than the preceding pulse 252. More specifically, the amplitude of the signal 250 increases from pulse 252a to pulse 252c, and then decreases from pulse 252c to pulse 252e. This pattern can then be repeated. In some embodiments, the signal 250 includes multiple pulses 252 at a-12-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 common amplitude before being ramped up or down to a different amplitude (e.g., multiple pulses are delivered with an amplitude equal to the pulse 252a before the signal 250 is ramped to delivering pulses with an amplitude equal to the pulse 252b). Although shown as being ramped in two directions, in other embodiments the signal 250 is ramped only in a single direction (e.g., the amplitude is either increased or decreased, but not both), until a maximum or minimum amplitude is reached.

[0043] In some embodiments, other parameters of the signal 250 (e.g., pulse width, interpulse interval, frequency, etc.) can remain constant (e.g., unchanged) as the amplitude of the pulses 252 is ramped. In other embodiments, one or more other parameters can be ramped, in addition to the amplitude being ramped. For example, in some embodiments both a pulse width and an amplitude of the pulses 252 is ramped. In such embodiments, the pulse width of the pulses 252 may be inversely ramped with the amplitude, such that as the amplitude increases, the pulse width decreases, and vice versa. Moreover, in some embodiments the pulse width, frequency, or other parameter is ramped instead of the amplitude.

[0044] In some embodiments, the electrical signals described herein (e.g., the signal 200 of Figure 2A and the signal 250 of Figure 2B) are administered during discrete stimulation sessions or periods that have a duration less than 24 hours. For example, the stimulation sessions may have a duration of between about 15 minutes and about 4 hours, or between about 15 minutes and about 3 hours, or between about 15 minutes and about 2 hours, or between about 30 minutes and about 3 hours, or between about 30 minutes and about 2 hours, or between about 30 minutes and about 1.5 hours, or between about 45 minutes and about 1 .5 hours. In some embodiments, the stimulation sessions can have a duration of about 5 minutes, about 15 minutes, about 30 minutes, about 45 minutes, about 1 hour, about 1.5 hours, about 2 hours, about 2.5 hours, about 3 hours, about 3.5 hours, or about 4 hours. The patient can receive one or more stimulation sessions per day. For example, in some embodiments the patient receives a single stimulation session per day. In other embodiments, the patient receives multiple (e.g., two, three, four, etc.) discrete stimulation sessions per day. During periods between stimulation sessions, the patient generally does not receive any stimulation, or at least any clinically meaningful stimulation. The foregoing representative stimulation period durations are provided by way of example only — in some embodiments, the electrical signals described herein may be applied during-13-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 stimulation sessions having different durations. One expected advantage of delivering stimulation during discrete stimulation sessions having a relatively short duration is that doing so may reduce the frequency with which the patient must recharge the power source in the signal generator. Another expected advantage is that it may reduce the likelihood the patient becomes desensitized (e.g., habituates) to the stimulation. In some embodiments, however, electrical stimulation is applied for 24 hours per day.

[0045] The electrical signals can be administered intermittently or continuously during the stimulation sessions. For example, the electrical signals can be administered continuously (e.g., without interruption) during the entirety of the stimulation session. Alternatively, the electrical signals can be administered intermittently, such that the signal is only actively delivered during portions of the stimulation sessions. In such embodiments, the stimulation session may cycle between "on" times during which the signal is being administered, and "off" times during which the signal is not being administered. In some embodiments, the "on" time can be between about 1 second and about 10 minutes, and the "off" time can be between about 1 second and about 10 minutes. Representative examples of suitable intermittent stimulation schedules include 10 seconds on, 10 seconds off; 10 seconds on, 30 seconds off; 10 seconds on, 60 seconds off; 10 seconds on, 90 seconds off; 30 seconds on, 30 seconds off; 30 seconds on, 60 seconds off; 30 seconds on, 90 seconds off; 1 minute on, 1 minute off; 10 minutes on, 10 minutes off, etc. The on times and off times are provided by way of example only — in some embodiments, the electrical signals described herein may be applied according to different on times and off times.

[0046] Regardless of whether the signal is administered intermittently or continuously during the stimulation sessions, the signal can be administered according to a duty cycle of between about 0.1 % and about 100% during each stimulation session. As used herein, and referring again to Figure 2A, the term duty cycle refers to the fraction of a single pulse period 201 (which consists of a single pulse 202 and a single interpulse interval 212) in which the pulse 202 is being actively delivered. That is, for a single pulse period, the duty cycle can be expressed as: (pulse width / duration of pulse period) x 100. For example, if a pulse period comprises (1 ) a bi-phasic pulse with no interphase interval and with each phase of the pulse having a pulse width of 500 microseconds, followed by (2) an interpulse interval having a duration of 99 milliseconds (e.g., before the following pulse period begins), the duty cycle is 1 % (1 millisecond-14-143662.8009.WO00M 82951419.1Attorney Docket No.: 143662.8009. WO00 combined pulse width / 100 millisecond pulse period duration, x 100). In this way, the term duty cycle is different than the term intermittent, which generally refers to delivering sequential pulse periods in a row for a first duration (e.g., 10 seconds), followed by a quiescent period during which no pulse periods are delivered for a second duration (e.g., for 90 seconds).C. Sacral Nerve Stimulation Lead Alignment Features and Associated Methods

[0047] As set forth above, the present technology includes an alignment system including alignment features for assisting with the placement of electrical leads (e.g., the lead 122 of Figure 1 A) at a target sacral nerve of a patient. As described further below, the alignment system comprises a primary alignment feature (e.g., an alignment grid) configured to lie flat against the patient's skin and a secondary alignment feature (e.g., an insertion guide) configured to be positioned over the primary alignment feature. As described in detail below, the primary alignment feature can include multiple sets of radiopaque grid lines forming a coordinate system that is visible in fluoroscopic images of a target foramen associated with the target sacral nerve. When an imaging device (e.g., an x-ray imaging device) obtains a first image that includes both the primary alignment feature and the target foramen (and / or the associated sacral nerve), the position of the target foramen can be correlated to a position on the primary alignment feature. This position helps medical personnel identify the correct location of the target foramen and / or target sacral nerve below the skin. A secondary alignment feature having one or more insertion markings can then be coupled to the primary alignment feature based on the correlated position of the target foramen, and provides an indication of the specific insertion point and insertion angle for a delivery instrument (e.g., a needle) carrying a signal delivery device (e.g., a stimulation lead) to deliver an electrical stimulation lead proximate the target foramen and / or nerve.

[0048] Figure 3A illustrates a first primary alignment feature 300 for providing a visual guide during a procedure for implanting a signal delivery device through a target sacral foramen of a patient and configured in accordance with some embodiments of the present technology. The primary alignment feature 300 can be designed to be positioned on and / or adhered to a target region of a patient's skin overlying the target sacral foramen. For example, the primary alignment feature 300 can be a flat (e.g., planar or at least substantially planar) panel having a generally rectangular shape. In-15-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 other embodiments, however, the primary alignment feature 300 can have a three- dimensional curvature designed to match a corresponding curvature of the target region of the patient's skin, and / or other suitable shapes, such as circular, oval-shaped, triangular, pentagonal, hexagonal, irregular, or the like. The size of the primary alignment feature 300 can be based on the target region of the patient's skin. In some embodiments, the size and / or shape of the primary alignment feature 300 can be designed to reduce or avoid interference with other aspects of the associated medical procedure. For example, the size and / or shape of the primary alignment feature 300 can be selected such that the primary alignment feature 300 does not cover a particular area of skin through which the signal generator 110 will be implanted. In some embodiments, the primary alignment feature 300 is at least 1 cm by 1 cm. For example, the primary alignment feature can have a dimension of between 1 -25cm by 1 -25cm, or between 3-20cm by 3-20cm, or between 5-15cm by 5-15cm. The foregoing ranges are provided by way of example only — in other embodiments, the primary alignment feature 300 can have dimensions outside the foregoing ranges.

[0049] Regardless of its shape and size, in some embodiments a first (e.g., lower) surface of the primary alignment feature 300 includes an adhesive for adhering the primary alignment feature 300 to the patient (e.g., similar to a sticker). In other embodiments however, the primary alignment feature 300 can be adhered to the patient using other suitable techniques (e.g., tape, glue, etc.), or can simply be laid over the patient. Regardless, the primary alignment feature is expected to easy to remove from the patient (e.g., after the procedure, to reposition, etc.) without causing patient pain or damage to the skin. In some embodiments, the primary alignment feature 300 can be at least partially flexible or elastic such that it can accommodate non-planar surfaces of the patient's skin (e.g., curves, protrusions, cavities, etc.). The primary alignment feature 300 can be generally radiolucent except for the particular radiopaque features described below.

[0050] The primary alignment feature 300 includes a first set or plurality of first grid lines 301 (individually labeled as 301 a-n) and a second set or plurality of second grid lines 302 (individually labeled as 302a-n). The first grid lines 301 are parallel to each other and extend vertically in the orientation shown in Figure 3A. The second grid lines 302 are also parallel to each other but extend horizontally in the orientation shown in Figure 3A. Accordingly, individual first grid lines 301 intersect orthogonally with-16-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 individual second grid lines 302. In the illustrated embodiment, the spacing between individual first grid lines 301 and the spacing between individual second grid lines 302 are equal or substantially equal. In other embodiments, however, the spacing between the first grid lines 301 and / or the spacing between the second grid lines 302 need not be equal or substantially equal. Further, although the illustrated embodiment shows 10 first grid lines 301 and 10 second grid lines 302, in some embodiments the primary alignment feature 300 can have more or fewer first grid lines 301 and / or second grid lines 302. For example, the primary alignment feature 300 can have between 5 and 50 first grid lines 301 and between 5 and 50 second grid lines 302. Moreover, although the illustrated embodiment shows that the primary alignment feature 300 has the same number of first grid lines 301 and second grid lines 302, in other embodiments the primary alignment feature 300 can have an unequal number of first grid lines 301 and second gride lines 302 (e.g., 10 first grid lines 301 and 15 second grid lines 302). The first grid lines 301 and the second grid lines 302 can be formed of a radiopaque material (e.g., a radiopaque ink, tape, etc.) such that they are visible in fluoroscopic (e.g., x-ray) images that include the primary alignment feature 300. The primary alignment feature 300 can therefore also be referred to as an "alignment grid" or a "positioning grid."

[0051] The primary alignment feature 300 can also include visual indicators or annotations for identifying individual first grid lines 301 and second grid lines 302. For example, the primary alignment feature 300 can have first grid line indicators or annotations 303 for identifying individual first grid lines 301 (e.g., individual first grid lines 301 include corresponding individual indicators A-J). Similarly, the primary alignment feature 300 can include second grid line indicators or annotations 304 for identifying individual second grid lines 302 (e.g., individual second grid lines 302 include corresponding individual indicators 1-10). Similar to the grid lines 301 and 302, the indicators 303 and 304 can also be formed of a radiopaque material (e.g., a radiopaque ink, tape, etc.) such that they are also visible in fluoroscopic (e.g., x-ray) images that include the primary alignment feature 300.

[0052] The primary alignment feature 300 can include additional markings / features. For example, in some embodiments the primary alignment feature 300 includes one or more landmarking features (not shown) that can be used to align the primary alignment feature 300 with visible anatomical structures, such as bony protuberances. These features can be incorporated into the shape of the labels, the-17-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 lines of the grid, or as standalone features. For example, the primary alignment feature 300 can include markers that align with prominent bony landmarks of the sacral area, as well as lines that contour to the natural curves of the sacrum and coccyx. In some embodiments, the shape of the label and / or the lines of the grid are shaped to outline the bony protuberances over which the primary alignment feature 300 lies. For example, the primary alignment feature 300 can include one or more markers indicating the location of a prominent bony landmark in the sacral area when the markers are positioned over the bony landmark. A user can align the primary alignment feature 300 on the patient using the landmarking features. In some embodiments, the landmarking features can optionally be formed of a radiopaque material similar to the first and second grid lines 301 , 302. As another example, the primary alignment feature 300 can include additional markings such as company branding, a sales-representative telephone number, a QR code that, when scanned, provides access to instructions for using the primary alignment feature 300, or the like.

[0053] In some embodiments, the primary alignment feature 300 is composed of a markable material that a user can annotate (e.g., using a pen, pencil, etc.). This enables a user to make direct markings within the grid formed by the grid lines 301 , 302, e.g., to mark the location of internal bony structures, etc. The material can also be configured to be pierced by a medical instrument (e.g., a needle carrying a stimulation lead). For example, the material can provide the same amount of resistance, or less resistance, to the needle than the patient's skin. Representative materials include, but are not limited to, paper, silicone sheets, polyurethane films, and the like. In some embodiments, the materials are sterile and / or biocompatible.

[0054] Figure 3B illustrates another primary alignment feature 310 configured in accordance with select embodiments of the present technology. The primary alignment feature 310 can be generally similar to the primary alignment feature 300 of Figure 3A, and so the description of the primary alignment feature 300 of Figure 3A applies equally to the primary alignment feature 310, except where the context clearly dictates otherwise. For example, the primary alignment feature 310 includes a first set or plurality of first grid lines 31 1 (individually labeled as 31 1 a-n), a second set or plurality of second grid lines 312 (individually labeled as 312a-n), first grid line indicators 313, and second grid line indicators 314. However, relative to the grid lines 301 , 302 of the primary alignment feature 300 of Figure 3A, some of the first grid lines 311 have different-18-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 characteristics. For example, the first first grid line 31 1 a has a first weight, the third first grid line 31 1 c is dashed, and the fifth first grid line 31 1 e has a second weight that is greater than the first weight. Similarly, the first second grid line 312a has a first weight, the third second grid line 31 1 c is dashed, and the fifth second grid line 312e has a second weight that is greater than the first weight. The lines with different characteristics can be arranged in other patterns and so the present technology is not limited to the pattern shown in Figure 3B. Indeed, as one skilled in the art will appreciate, any combination of the first and second grid lines 31 1 , 312 can have any combination or pattern of different characteristics. Further, in addition to or in lieu of varying the weight of the line or providing dashed lines, the lines 311 , 312 can be varied in other suitable manners (e.g., some lines can be dotted, curvy, double-dashed, etc.). Without intending to be bound by theory, providing grid lines having different characteristics may better assist a doctor or other healthcare provider with correlating an underlying target sacral foramen to a position on the primary alignment feature 310.

[0055] Figure 3C illustrates yet another primary alignment feature 320 configured in accordance with select embodiments of the present technology. The primary alignment feature 320 can also be generally similar to the primary alignment feature 300 of Figure 3A, and so the description of the primary alignment feature 300 of Figure 3A applies equally to the primary alignment feature 320, except where the context clearly dictates otherwise. For example, the primary alignment feature 320 includes a first set or plurality of first grid lines 321 (individually labeled as 321 a-n), a second set or plurality of second grid lines 322 (individually labeled as 322a-n), first grid line indicators 323, and second grid line indicators 324. However, relative to the primary alignment feature 300 of Figure 3A, individual first grid lines 321 are not parallel to one another, and individual second grid lines 322 are not parallel to one another. Further, the first grid lines 321 are non-orthogonal (e.g., do not form right angles) with the second grid lines 322. Without intending to be bound by theory, providing non-parallel and / or non-orthogonal grid lines may provide better or more targeted coverage of a target area on the surface of a patient's skin, and thus may better assist a doctor or other healthcare provider with correlating an underlying target sacral foramen to a position on the primary alignment feature 320.

[0056] As one skilled in the art will appreciate, various features of the primary alignment features 300, 310, and 320 can be combined to provide additional-19-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 embodiments of primary alignment features. For example, primary alignment features of the present technology can include any combination of lines having different characteristics, parallel and / or non-parallel lines, orthogonal and / or non-orthogonal lines, and the like.

[0057] The primary alignment guides described herein can be used to assist a physician or other healthcare provider with determining a target insertion point for a procedure for implanting a signal delivery device (e.g., the signal delivery device 120 of Figure 1A) through a target sacral foramen and proximate a target sacral nerve of a patient. For example, Figure 4A is an anterior view of the primary alignment feature 300 of Figure 3A positioned on a surface of a patient's skin overlying a sacral region of the patient and in accordance with some embodiments of the present technology. As shown, the primary alignment feature 300 can be coupled to and / or positioned on the patient such that it overlaps with at least some portion of one or more of the sacral foramen S1 , S2, S3, and S4 when viewed from a posterior direction.

[0058] In operation, a physician or other healthcare provider can use an imaging device to capture a first image of the patient that includes both the primary alignment feature 300 and a target foramen (e.g., the S3 foramen) associated with a target sacral nerve. In some embodiments, the imaging device is a fluoroscopic imaging device or other x-ray device. When the imaging device captures an image including the target foramen and the primary alignment feature 300, the radiopaque grid lines 303, 304 of the primary alignment feature 300 create a coordinate system visible in the fluoroscopic image. For example, when an anterior-posterior (AP) x-ray image is captured, the x-ray image will show the grid lines 303, 304 overlaid over the bony anatomy of the patient, and the location of the target foramen can be identified relative to coordinates of intersecting grid lines. In the illustrated embodiment, for example, the S3 foramen is located approximately between the first grid lines 303 labeled F and H, and the second grid lines 304 labeled 5 and 6. The user can identify this location by reviewing the x-ray image. The user can then place a visible marker (not shown in Figure 4A) on the primary alignment feature 300 at the identified location. In some embodiments, the marker can indicate a target insertion point at which a needle carrying a stimulation lead should be inserted into the patient so that it can be advanced through the target sacral foramen. In some embodiments, the insertion point is slightly offset from the target foramen to account for an insertion angle. Accordingly, in some embodiments the mark can be-20-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 placed on the primary alignment feature 300 at a position that is not directly "above" the target foramen.

[0059] In some embodiments, the visible marker can be made by a marker or pen. In other embodiments, a secondary alignment feature can be placed upon and / or coupled to the primary alignment feature to indicate the target insertion point. In some embodiments, the secondary alignment feature can include a sticker or label that can be placed on the primary alignment feature at the target insertion point, as described in detail below with reference to Figure 5A. In yet other embodiments, the secondary alignment feature can be a three-dimensional structure that provides information on an insertion direction and / or insertion angle in addition to designating the target insertion point, such as described below with reference to Figures 5B-7.

[0060] Figure 4B is an anterior view of the primary alignment feature 310 of Figure 3B positioned on the surface of a patient's skin overlying the sacral region of the patient. The primary alignment feature 310 can be used similarly as the primary alignment feature 300 described above with reference to Figure 4A. For example, a fluoroscopic image that includes the primary alignment feature 310 and the patient's bony anatomy can be used to identify, within a coordinate system created by the grid lines 313, 314, an insertion point for advancing a stimulation lead through a target sacral foramen. A visible marker and / or secondary alignment feature can then be placed on the primary alignment feature 310 at the target insertion point.

[0061] In addition to the primary alignment features described above, the present technology further includes secondary alignment features that can be placed on and / or coupled to the primary alignment feature. The secondary alignment features can (1 ) identify a target insertion point on the primary alignment feature, and / or (2) provide an insertion angle guide and / or an insertion direction guide for guiding insertion of a needle carrying a stimulation lead during an implant procedure (the secondary alignment feature can therefore also be referred to as an insertion guide, an insertion angle guide, an insertion direction guide, or the like).

[0062] Figure 5A illustrates a first embodiment of a secondary alignment feature 500 configured in accordance with some embodiments of the present technology. As shown, the secondary alignment feature 500 includes a flat (e.g., planar or substantially planar) label (e.g., an adhesive sticker) that can be positioned on and / or coupled to an-21 -143662.8009. WO00X18295141 .1Attorney Docket No.: 143662.8009. WO00 alignment grid (e.g., any of the primary alignment features discussed with reference to Figures 3A-4B) to provide an indication of where a medical instrument, such as a needle, can puncture the skin to access the target foramen (e.g., the S3 foramen) and the associated target sacral nerve. For example, the insertion guide 500 can include a center point C. Based on the captured image of the primary alignment feature and the target foramen, the center point C of the insertion guide 500 is positioned over the target foramen. In some embodiments, the insertion guide 500 is placed directly over the target foramen (e.g., between the first grid lines 301 labeled F and H, and the second grid lines 302 labeled 5 and 6 in the example of Figure 4A, assuming the target foramen is S3). In some embodiments, the insertion guide 500 is offset / shifted a distance from the grid lines closest to the target foramen, to account for an angled approach to the target foramen. However, because the secondary alignment feature 500 is planar, the secondary alignment feature 500 does not assist with controlling an angle of insertion of the needle.

[0063] Figure 5B is a perspective view of a second embodiment of a secondary alignment feature 510 for controlling an insertion point, an insertion angle, and an insertion direction and that is configured in accordance with embodiments of the present technology. Figure 5C is another perspective view of the secondary alignment feature 510 of Figure 5B, rotated approximately 90 degrees counterclockwise relative to the view of Figure 5B. Figures 5B and 5C show the secondary alignment feature 510 in a "folded" or "upright" configuration (discussed further herein). Figure 5D illustrates the secondary alignment feature 510 of Figures 5B and 5C in an "unfolded" or "flat" configuration.

[0064] Referring collectively to Figures 5B-5D, the secondary alignment feature 510 includes a first section 520 including an insertion point C and one or more radiopaque angle indicator markings and / or lines 522 (also referred to as angle indicators). The angle indicator lines 522 can extend at different angles along the first section 520, such as between +40 degrees to -40 degrees, although in other embodiments the angle indicator lines 522 can extend at greater or lesser angles, and / or include more or fewer increments between +40 and -40 degrees. To further enhance a user's ability to distinguish individual angle indicator lines 522, the lines 522 can have different characteristics, similar to the grid lines 31 1 , 312 described above with reference to Figure 3B. As described in greater detail below, the angle indicator-22-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 lines 522 can be visible to a user when the secondary alignment feature 510 is positioned on a primary alignment feature to help assist in controlling an insertion point, an insertion angle, and / or an insertion direction.

[0065] The secondary alignment feature 510 also includes a second section 530 configured to support the first section 520 when the secondary alignment feature 510 is folded along one or more first joints J1 , and one or more third sections 540 configured to act as a base or stand for the secondary alignment feature when the secondary alignment feature 510 is folded along one or more second joints J2. As shown in Figures 5B and 5C, the secondary alignment feature 510 is configured to form an upright stand when folded along the first joints J1 and the second joints J2. That is, the first section 520 including the angle indicator markings 522 extends in a plane that is not parallel to or the same as the planes occupied by the second section 530 or the third sections 540. For example, the first section 520 can be configured to form an angle relative to the third sections 540 of between about 15 degrees and about 90 degrees, or between about 30 degrees and about 90 degrees, or between about 45 degrees and about 90 degrees. As described in greater detail below, this enables a user to use the angle indicator markings 522 to control an angle of insertion of a delivery device and / or enables a user to see the angle indicator markings 522 when the secondary alignment feature 510 is included in a lateral fluoroscopic image.

[0066] The secondary alignment feature 510 is configured to be coupled to and / or positioned upon a primary alignment feature (e.g., any of the primary alignment features discussed with reference to Figures 3A-3C). For example, the third sections 540 can be placed on the primary alignment feature to act as a base for the secondary alignment feature 510. In some embodiments, the third sections 540 are coated in an adhesive material and / or substance, such as glue or a silicone-based polymer, or include tape or other adhesive surface. The secondary alignment feature 510 is configured to be both couplable and decouplable from the primary alignment feature such that the secondary alignment feature 510 can be repositioned as needed (e.g., after capturing fluoroscopic image data including the target foramen and the secondary alignment feature 510).

[0067] For example, Figure 6A is a perspective view of the primary alignment feature 310 of Figure 3B being used in combination with the secondary alignment feature 510 of Figures 5B-5D in accordance with some embodiments of the present-23-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 technology. Figure 6B is another perspective view of the primary alignment feature 310 of Figure 3B being used in combination with the secondary alignment feature 510 of Figures 5B-5D, rotated approximately 90 degrees in a clockwise direction relative to Figure 6A. As shown, the third sections can be placed on and / or adhered to the primary alignment feature 310. As a result, the second section 520 extends away from the surface of the primary alignment feature 310 at an angle between about 15 degrees and about 90 degrees, or between about 30 degrees and 90 degrees, or between about 45 degrees and about 90 degrees. That is, the second section 520 is non-planar with the primary alignment feature 310.

[0068] The secondary alignment feature 510 can be coupled to and / or positioned on the primary alignment feature 310 at specific location and at a specific orientation. The specific location and the specific orientation can be determined based on fluoroscopic images of the patient and a target sacral foramen and sacral nerve. For example, the secondary alignment feature 510 can be positioned such that the insertion point C (Figure 5B) aligns with a determined target insertion point on the primary alignment feature. The secondary alignment feature 510 can also be oriented such that the second region aligns generally with the determined direction of insertion. Finally, the angle indicator lines 522 (Figure 5B) can show different insertion angles, one of which can be selected as the target insertion angle. In this way, the secondary alignment feature 510 can assist with setting / determining a target insertion point, a target insertion direction, and a target insertion angle.

[0069] Figure 7 is a partially schematic lateral view of the secondary alignment feature 510 of Figures 5B-5D positioned in accordance with some embodiments of the present technology. As shown in Figure 7, the +20 degree angle indicator is approximately parallel to, and aligned with, a plane 760 of a target sacral joint associated with a target foramen, S3. Thus, the +20 degree angle indicator can be used to help align a medical instrument for penetration through the skin S of patient P to access the target foramen, S3. In some embodiments, multiple fluoroscopic images depicting the position / orientation of the secondary alignment feature 510 relative to the plane 760 of the target sacral joint (or other anatomical feature / landmark) are used to align and / or realign the secondary alignment feature 510 until at least one of the angle indicators is approximately parallel to the plane 760.-24-143662.8009.WO00M 82951419.1Attorney Docket No.: 143662.8009. WO00

[0070] Figure 8 is a flowchart of a method 800 of implanting a sacral nerve stimulation lead through a target sacral foramen and proximate a target sacral nerve in accordance with some embodiments of the present technology. The method 800 can begin at block 802, by identifying a target foramen that is associated / correlated with a target sacral nerve for electrical stimulation treatment for a patient. For example, in embodiments in which the right S3 sacral nerve is the target nerve for treatment, the corresponding right S3 foramen can be identified as the target foramen. In embodiments in which the left S3 sacral nerve is the target nerve for treatment, the corresponding left S3 foramen can be identified as the target foramen. In some embodiments, the operation at block 802 can be omitted and the method 800 can begin at block 804.

[0071] The method 800 can continue at block 804, by positioning a primary alignment feature on a skin of the patient in the area of the target foramen. The primary alignment feature includes multiple sets (e.g., a first set and a second set) of radiopaque lines that form a grid-like pattern. For example, the primary alignment feature can be generally similar to or the same as the primary alignment features 300, 310, or 320 of Figures 3A-3C. In some embodiments, positioning the primary alignment feature on the patient's skin includes adhering or sticking the primary alignment feature to the patient's skin. In other embodiments, however, the primary alignment feature is simply laid over the top of the patient's skin. In some embodiments, the primary alignment feature can be initially positioned based on mitigating and / or preventing interference with other aspects of the medical procedure, such as avoiding covering up a particular area of skin through which a signal generator will be implanted. In some embodiments, the primary alignment feature can include landmarking features that a user can align with visual anatomical structures (e.g., bony protuberances) to facilitate placement of the primary alignment feature.

[0072] The method 800 can continue at block 806 by capturing a first image of the primary alignment feature and at least the target foramen (e.g., via a fluoroscopic imaging device). In some embodiments, the first image can be an anterior-posterior x- ray image that includes both the primary alignment feature and at least some of the sacral bony anatomy of the patient. In other embodiments, the first image can be taken from other angles / views, and / or can include other anatomical structures.-25-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00

[0073] The method 800 can optionally continue at block 807 by determining a location within the grid lines of the primary alignment feature that directly overlies the target sacral foramen (e.g., the target foramen location). For example, if the target sacral foramen is the S3 foramen, the target foramen location can be the point within the grid lines of the primary alignment feature that sits directly above the S3 foramen when the patient is prone. A mark can optionally be placed at the target foramen location. In some embodiments, the operation at block 807 is skipped and the method 800 proceeds directly to the operation at block 808.

[0074] The method 800 can continue at block 808 by determining a target insertion point, a target insertion angle, and / or a target insertion direction based on the first image. The target insertion point can refer to a location on the patient at which a puncture should be made by a delivery device (e.g., needle) carrying the signal delivery device (e.g., stimulation lead). The target insertion point can be the same as or different than the target foramen location. The target insertion angle refers to the angle (e.g., 15 degrees, 30 degrees, 45 degrees, 60 degrees, etc.) the delivery device should be inserted at such that it travels from the insertion point to the target sacral foramen. The target insertion direction refers to the direction (e.g., medial to lateral, rostral to caudal, etc.) the lead should be inserted in. Collectively, the target insertion point, target insertion angle, and target insertion direction define the pathway a delivery device (e.g., needle) carrying the stimulation lead should be implanted via such that it can be advanced through the target foramen.

[0075] In some embodiments, determining the target insertion point, the target insertion angle, and / or the target insertion direction includes analyzing the first image to determine a preferred path to the sacral foramen. For example, the target insertion point, target insertion angle, and / or target insertion direction can be selected based at least part on (a) minimizing a distance between the target insertion point and the target foramen, (b) providing an optimal angle for entering the sacral foramen, (c) avoiding anatomical structures such as other bony structures, muscles, tendons, scar tissue, or the like, (d) physician preferences, (e) combinations thereof, and / or other factors. The target insertion point, target insertion angle, and / or target insertion direction can be determined by a user (e.g., the physician) or a computing system having a software module programmed to analyze the first image and to provide a recommended target-26-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 insertion point, target insertion angle, and / or target insertion direction based on the analysis.

[0076] In some embodiments, the operation at block 808 includes determining the target insertion point based on the first image, and then determining the target insertion angle and the target insertion direction based on the target insertion point. In other embodiments, the operation at block 808 includes determining the target insertion angle and target insertion direction based on the first image, and then determining the target insertion point based on the target insertion angle and the target insertion direction. In other embodiment, the operation at block 808 includes determining each of the target insertion point, the target insertion angle, and the target insertion direction.

[0077] After the target insertion point, target insertion angle, and / or target insertion direction are determined at block 808, the method 800 can continue at block 810 by positioning a secondary alignment feature on the primary alignment feature based on the determined target insertion point, target insertion angle, and / or target insertion direction. The secondary alignment feature can be generally similar to or the same as the secondary alignment features 500 and 510 of Figures 5A-5D. Accordingly, the secondary alignment feature can include a range of angle indicator lines (e.g., angle markings) from -40 to +40 degrees relative to the insertion point. The angle indicator that matches or approximately matches the target insertion angle to the target foramen (e.g., +20 degrees) can be selected and used to align and guide a medical instrument into the skin of the patient during the implant procedures, as described below. In some embodiments, positioning the secondary alignment feature on the primary alignment feature includes adhering or sticking the secondary alignment feature to the primary alignment feature. In other embodiments, however, the secondary alignment feature is simply laid on the primary alignment feature.

[0078] In embodiments in which the insertion point and target foramen location are co-located, the secondary alignment feature can simply be placed such that an insertion marker of the secondary alignment feature (e.g., a center point of the secondary alignment feature) is positioned directly over the co-located insertion point and target foramen. In embodiments in which the insertion point and the target foramen location are not co-located, the secondary alignment feature can be positioned on the primary alignment feature such that it is offset a distance from the target foramen location, e.g.,-27-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO00 to accommodate an angled entry of a medical device into the skin of the patient. In such embodiments, the secondary alignment feature can include angle indicators to assist with guiding the medical instrument at the target insertion angle into the skin and to the target foramen and / or target sacral nerve, as shown in block 816.

[0079] The method 800 can optionally continue at block 812 by capturing a second image including the secondary alignment feature and at least the target foramen. In some embodiments, the second image can be a lateral x-ray image that includes both the secondary alignment feature and at least some of the sacral bony anatomy of the patient. In other embodiments, the second image can be taken from other angles / views, and / or can include other anatomical structures. In some embodiments, the secondary alignment feature is comprised of a first section that includes one or more radiopaque angle indicators, and a second section configured to support the first section when one or more malleable joints of the secondary alignment feature are folded to form an upright or generally upright stand. The secondary alignment feature can be folded such that the first section including the angle indicators is approximately perpendicular to the skin of the patient, approximately parallel to the sagittal plane of the patient, and facing an imaging device (e.g., an x-ray of a lateral view of the sacral region of the patient). The imaging device can thus capture a second image including the angle indicators of the secondary alignment feature and the target foramen.

[0080] If a second image including the secondary alignment feature is captured at block 812, the method 800 can continue at block 814 by confirming and / or setting the insertion angle and insertion direction based on the second image. This can include, for example, analyzing the second image to confirm that if a delivery instrument (e.g., needle) is inserted into the patient at the target insertion point, the target insertion angle, and the target insertion direction, the delivery instrument will advance through the target foramen.

[0081] In some embodiments, an alignment of the secondary alignment feature is changed based on the second image. For example, the second image can include the radiopaque angle indicators of the secondary alignment feature, and an image of an anatomical feature and / or landmark. The secondary alignment feature can be aligned based on a plane corresponding to the anatomical feature. In some embodiments, the anatomical feature includes a target sacral joint corresponding to the target foramen-28-143662.8009. WO00X18295141 .1Attorney Docket No.: 143662.8009. WO00 and / or target sacral nerve. A plane of the target sacral joint can be used to align the secondary alignment feature such that one of the radiopaque angle indicators is approximately parallel and / or in-line with the plane of the target sacral joint. Once aligned, the radiopaque angle indicator that is closest to and / or matches the plane of the target sacral joint can be used to align and guide the delivery instrument into the skin of the patient.

[0082] The method 800 can continue at block 816 by aligning the delivery instrument (e.g., a delivery needle) carrying the signal delivery device (e.g., stimulation lead) based on the primary alignment feature and the secondary alignment feature. This includes, for example, preparing to insert the delivery instrument into the patient at the target insertion point, the target insertion angle, and the target insertion direction. A user can then advance the delivery instrument into the patient and though the target sacral foramen, and deploy the signal delivery device proximate the target sacral nerve.D. Representative Examples

[0083] The following examples are provided to further illustrate embodiments of the present technology and are not to be interpreted as limiting the scope of the present technology. To the extent that certain embodiments or features thereof are mentioned, it is merely for purposes of illustration and, unless otherwise specified, is not intended to limit the present technology. It will be understood that many variations can be made in the procedures described herein while still remaining within the bounds of the present technology. Such variations are intended to be included within the scope of the presently disclosed technology.1 . A stimulation lead alignment system for delivering an electrical stimulation lead to a target sacral nerve of a patient, the system comprising: a primary alignment feature including a first surface having: a plurality of first radiopaque grid lines extending in a first direction, and a plurality of second radiopaque grid lines extending in a second direction different from the first direction, wherein each of the first radiopaque grid lines intersects with each of the second radiopaque grid lines to form a grid; and-29-143662.8009. WO00X18295141 .1Attorney Docket No.: 143662.8009. WOOO a secondary alignment feature including a second surface having a plurality of insertion angle lines, wherein the secondary alignment feature is removably couplable to or positionable on the first surface of the primary alignment feature such that the first surface and the second surface are non-planar.2. The system of example 1 wherein the first radiopaque grid lines are parallel to each other, and wherein the second radiopaque grid lines are parallel to each other.3. The system of example 1 or example 2 wherein the first radiopaque grid lines are orthogonal to the second radiopaque grid lines.4. The system of example 1 or example 2 wherein the first radiopaque grid lines are non-orthogonal to the second radiopaque grid lines.5. The system of any of examples 1 -4 wherein at least some individual first radiopaque grid lines have a different characteristic than at least some other individual first radiopaque grid lines.6. The system of any of examples 1 -5 wherein the secondary alignment feature includes a first section having the first surface and one or more second sections, wherein the one or more second sections are configured to act as a base for the second alignment feature, and wherein the one or more second sections occupy a different plane than the first section.7. The system of example 6 wherein the one or more second sections include an adhesive for removably coupling the secondary alignment feature to the primary alignment feature.-30-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WOOO8. A stimulation lead alignment system for delivering an electrical stimulation lead to a target sacral nerve of a patient, the system comprising: a primary alignment feature having a first planar surface with a plurality of radiopaque grid lines; and a secondary alignment feature having a second planar surface with a plurality of insertion angle guide lines, wherein the secondary alignment feature is removably coupleable to and / or positionable on the primary alignment feature such that a relative position between the primary alignment feature and the secondary alignment feature is adjustable, and wherein, when the secondary alignment feature is coupled to and / or positioned on the primary alignment feature, the first planar surface and the second planar surface extend within different planes.9. The system of example 8 wherein the second planar surface has a first edge configured to be spaced apart from the primary alignment feature and a second edge configured to abut the primary alignment feature, and wherein the plurality of insertion angle guide lines converge to a common location at the second edge.10. The system of example 8 or example 9 wherein at least some of the plurality of insertion angle guide lines have different characteristics.1 1. The system of any of examples 8-10 wherein the secondary alignment feature further includes a third planar surface, wherein the third planar surface is not parallel to the second planar surface, and wherein, when the secondary alignment feature is coupled to or positioned on the primary alignment feature, the third planar surface is parallel to the first planar surface.12. The system of example 1 1 wherein the third planar surface includes an adhesive for removably coupling the secondary alignment feature to the primary alignment feature.-31 -143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WOOO13. A method of delivering an electrical stimulation lead through a target sacral foramen and to target sacral nerve of a patient, the method comprising: positioning a primary alignment feature on a skin of the patient in an area overlying the target foramen, the primary alignment feature including a plurality of first radiopaque grid lines intersecting with a plurality of second radiopaque grid lines to form a grid; capturing an image of the primary alignment feature the target foramen; correlating a position of the target sacral foramen to a position on the grid formed by the first radiopaque grid lines and the second radiopaque grid lines based on the image; determining a target insertion point, target insertion angle, and / or target insertion direction for a delivery instrument carrying the stimulation lead based on the image and the correlated position; removably positioning a secondary alignment feature one the primary alignment feature based on the determined target insertion point, target insertion angle, and / or target insertion direction; and using the secondary alignment feature to implant the stimulation lead at the target sacral nerve via the target insertion point, target insertion angle, and / or target insertion direction.14. The method of example 13 wherein the first image is an x-ray image taken along an anterior-posterior direction.15. The method of example 13 or example 14 wherein correlating a position of the target sacral foramen to a position on the grid includes determining a position on the grid that directly overlies the target sacral foramen.16. The method of any of examples 13-15 wherein determining the target insertion point, the target insertion angle, and / or the target insertion direction includes analyzing the first image to determine a preferred delivery path the target sacral foramen.-32-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WO0017. The method of any of examples 13-16 wherein determining the target insertion point, the target insertion angle, and / or the target insertion direction includes determining each of the target insertion point, target insertion angle, and target insertion direction based on the image.18. The method of any of examples 13-17, further comprising capturing a second image including the secondary alignment feature and the target foramen after removably positioning the secondary alignment feature on the primary alignment feature.19. The method of example 18, further comprising determining the insertion angle based on the second image.20. The method of example 18 or example 19 further comprising repositioning the secondary alignment feature relative to the primary alignment feature based on the second image.E. Conclusion

[0084] From the foregoing, it will be appreciated that specific embodiments of the disclosed technology have been described herein for purposes of illustration, but that various modifications may be made without deviating from the technology. For example, electrical signals described herein can be delivered at combinations of parameter values within the foregoing ranges at values that are not expressly disclosed herein. Certain aspects of the technology described in the context of particular embodiments may be combined or eliminated in other embodiments. Further, while advantages associated with certain embodiments of the disclosed technology have been described in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments need necessarily exhibit such advantages to fall within the scope of the present technology. Accordingly, the disclosure and associated technology can encompass other embodiments not expressly shown or described herein.

[0085] The use of "and / or," as in "A and / or B" refers to A alone, B alone, and both A and B. Additionally, the term "comprising" is used throughout to mean including at-33-143662.8009. WO00X18295141 .1Attorney Docket No.: 143662.8009. WOOO least the recited feature(s) such that any greater number of the same feature and / or additional types of other features are not precluded. It will also be appreciated that specific embodiments have been described herein for purposes of illustration, but that various modifications may be made without deviating from the technology. Further, while advantages associated with certain embodiments of the technology have been described in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments need necessarily exhibit such advantages to fall within the scope of the technology. Accordingly, the disclosure and associated technology can encompass other embodiments not expressly shown or described herein.

[0086] Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, to between the upper and lower limits of that range is also specifically disclosed. Each smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in that stated range is encompassed within the disclosure. The upper and lower limits of these smaller ranges may independently be included or excluded in the range, and each range where either, neither or both limits are included in the smaller ranges is also encompassed within the disclosure, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the disclosure.-34-143662.8009. WOOOX18295141 .1

Claims

Attorney Docket No.: 143662.8009. WOOOCLAIMS l / We claim:1 . A stimulation lead alignment system for delivering an electrical stimulation lead to a target sacral nerve of a patient, the system comprising: a primary alignment feature including a first surface having: a plurality of first radiopaque grid lines extending in a first direction, and a plurality of second radiopaque grid lines extending in a second direction different from the first direction, wherein each of the first radiopaque grid lines intersects with each of the second radiopaque grid lines to form a grid; and a secondary alignment feature including a second surface having a plurality of insertion angle lines, wherein the secondary alignment feature is removably couplable to or positionable on the first surface of the primary alignment feature such that the first surface and the second surface are non-planar.

2. The system of claim 1 wherein the first radiopaque grid lines are parallel to each other, and wherein the second radiopaque grid lines are parallel to each other.

3. The system of claim 1 wherein the first radiopaque grid lines are orthogonal to the second radiopaque grid lines.

4. The system of claim 1 wherein the first radiopaque grid lines are non- orthogonal to the second radiopaque grid lines.

5. The system of claim 1 wherein at least some individual first radiopaque grid lines have a different characteristic than at least some other individual first radiopaque grid lines.

6. The system of claim 1 wherein the secondary alignment feature includes a first section having the first surface and one or more second sections, wherein the-35-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WOOO one or more second sections are configured to act as a base for the second alignment feature, and wherein the one or more second sections occupy a different plane than the first section.

7. The system of claim 6 wherein the one or more second sections include an adhesive for removably coupling the secondary alignment feature to the primary alignment feature.

8. A stimulation lead alignment system for delivering an electrical stimulation lead to a target sacral nerve of a patient, the system comprising: a primary alignment feature having a first planar surface with a plurality of radiopaque grid lines; and a secondary alignment feature having a second planar surface with a plurality of insertion angle guide lines, wherein the secondary alignment feature is removably coupleable to and / or positionable on the primary alignment feature such that a relative position between the primary alignment feature and the secondary alignment feature is adjustable, and wherein, when the secondary alignment feature is coupled to and / or positioned on the primary alignment feature, the first planar surface and the second planar surface extend within different planes.

9. The system of claim 8 wherein the second planar surface has a first edge configured to be spaced apart from the primary alignment feature and a second edge configured to abut the primary alignment feature, and wherein the plurality of insertion angle guide lines converge to a common location at the second edge.

10. The system of claim 8 wherein at least some of the plurality of insertion angle guide lines have different characteristics.1 1 . The system of claim 8 wherein the secondary alignment feature further includes a third planar surface, wherein the third planar surface is not parallel to the second planar surface, and wherein, when the secondary alignment feature is coupled-36-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WOOO to or positioned on the primary alignment feature, the third planar surface is parallel to the first planar surface.

12. The system of claim 1 1 wherein the third planar surface includes an adhesive for removably coupling the secondary alignment feature to the primary alignment feature.

13. A method of delivering an electrical stimulation lead through a target sacral foramen and to target sacral nerve of a patient, the method comprising: positioning a primary alignment feature on a skin of the patient in an area overlying the target foramen, the primary alignment feature including a plurality of first radiopaque grid lines intersecting with a plurality of second radiopaque grid lines to form a grid; capturing an image of the primary alignment feature the target foramen; correlating a position of the target sacral foramen to a position on the grid formed by the first radiopaque grid lines and the second radiopaque grid lines based on the image; determining a target insertion point, target insertion angle, and / or target insertion direction for a delivery instrument carrying the stimulation lead based on the image and the correlated position; removably positioning a secondary alignment feature one the primary alignment feature based on the determined target insertion point, target insertion angle, and / or target insertion direction; and using the secondary alignment feature to implant the stimulation lead at the target sacral nerve via the target insertion point, target insertion angle, and / or target insertion direction.

14. The method of claim 13 wherein the first image is an x-ray image taken along an anterior-posterior direction.

15. The method of claim 13 wherein correlating a position of the target sacral foramen to a position on the grid includes determining a position on the grid that directly overlies the target sacral foramen.-37-143662.8009. WOOOX18295141 .1Attorney Docket No.: 143662.8009. WOOO16. The method of claim 13 wherein determining the target insertion point, the target insertion angle, and / or the target insertion direction includes analyzing the first image to determine a preferred delivery path the target sacral foramen.

17. The method of claim 13 wherein determining the target insertion point, the target insertion angle, and / or the target insertion direction includes determining each of the target insertion point, target insertion angle, and target insertion direction based on the image.

18. The method of claim 13, further comprising capturing a second image including the secondary alignment feature and the target foramen after removably positioning the secondary alignment feature on the primary alignment feature.

19. The method of claim 18, further comprising determining the insertion angle based on the second image.

20. The method of claim 18 further comprising repositioning the secondary alignment feature relative to the primary alignment feature based on the second image.-38-143662.8009. WOOOX18295141 .1

Images