Onset-mitigating high-frequency nerve block

Abstract

A method of blocking signal transmission through a nerve, with reduced onset activity includes applying an HFAC to an axon of a nerve to block the transmission of signals through the axon. The method may also include applying a direct current (DC) to the axon, increasing the amplitude of the DC over time to a predetermined amplitude, applying the HFAC, and then decreasing the DC. The method may also include temporarily reducing the amplitude of the HFAC to permit the transmission of signals through the axon and subsequently increasing the amplitude to block transmission without triggering an onset response. The method may also include temporarily applying an unbalanced charge to the nerve and then balancing the charge over time.

1 - 38 . (canceled) 
     
     
         39 . A method for closed-loop nerve block, the method comprising:
 detecting, from at least one sensor in electrical communication with a nerve of a patient, a signal indicative of pain in the patient;   generating, from a waveform generator coupled to a controller, a nerve block signal when the controller indicates that a nerve block is required, the nerve block signal having a frequency of greater than 1 kHz and an amplitude of approximately 4 to 10 volts per pulse;   adjusting, by the controller, the nerve block signal based on closed-loop feedback from the at least one sensor; and   applying the nerve block signal to the nerve of the patient from one or more electrodes coupled to the waveform generator.   
     
     
         40 . The method of  claim 39 , wherein the pain is related to at least one of neuroma pain, cancer pain, post-operative pain, and chronic pain. 
     
     
         41 . The method of  claim 39 , wherein the pain is associated with a missing appendage. 
     
     
         42 . The method of  claim 39 , further comprising adjusting the nerve block signal as the nerve block signal is applied based on closed-loop feedback from the at least one sensor. 
     
     
         43 . The method of  claim 39 , wherein adjusting the nerve block signal comprises adjusting the frequency, voltage and current base on inputs from the at least one sensor. 
     
     
         44 . The method of  claim 39 , wherein the nerve block is one or more of an efferent neuron block, an afferent neuron block, and an interneuron block. 
     
     
         45 . The method of  claim 39 , further comprising closing, by the controller, a switch between the waveform generator and the one or more electrodes when the controller determines that nerve block is required. 
     
     
         46 . The method of  claim 39 , wherein the controller is implanted in the patient. 
     
     
         47 . The method of  claim 39 , wherein the waveform generator generates the nerve block signal having a current of between 1 milliamp and 12 milliamps. 
     
     
         48 . The method of  claim 39 , wherein generating the nerve block signal comprises generating a first high frequency alternating current (HFAC). 
     
     
         49 . The method of  claim 48 , wherein applying the nerve block signal comprises applying a DC signal in combination with the HFAC. 
     
     
         50 . A method for closed-loop nerve block, the method comprising:
 detecting, from at least one sensor in electrical communication with a nerve of a patient, a signal indicative of a pain associated with a missing appendage in the patient;   generating, from a waveform generator coupled to a controller, a nerve block signal when the controller indicates that a nerve block is required, the nerve block signal having a frequency of greater than 1 kHz and an amplitude of approximately 4 to 10 volts per pulse;   adjusting, by the controller, the nerve block signal based on closed-loop feedback from the at least one sensor; and   applying the nerve block signal to the nerve of the patient from one or more electrodes coupled to the waveform generator, wherein the nerve block signal is adjusted as the nerve block signal is applied based on closed-loop feedback from the at least one sensor.   
     
     
         51 . The method of  claim 50 , wherein adjusting the nerve block signal comprises adjusting the frequency, voltage and current base on inputs from the at least one sensor. 
     
     
         52 . The method of  claim 50 , wherein the nerve block is one or more of an efferent neuron block, an afferent neuron block, and an interneuron block. 
     
     
         53 . The method of  claim 50 , further comprising closing, by the controller, a switch between the waveform generator and the one or more electrodes when the controller determines that nerve block is required. 
     
     
         54 . The method of  claim 50 , wherein the controller is implanted in the patient. 
     
     
         55 . The method of  claim 50 , wherein the waveform generator generates the nerve block signal having a current of between 1 milliamp and 12 milliamps. 
     
     
         56 . The method of  claim 50 , wherein generating the nerve block signal comprises generating a first high frequency alternating current (HFAC). 
     
     
         57 . The method of  claim 56 , wherein applying the nerve block signal comprises applying a DC signal in combination with the HFAC. 
     
     
         58 . A method for closed-loop nerve block, the method comprising:
 detecting, from at least one sensor in electrical communication with a nerve of a patient, a signal indicative of a pain associated with a missing appendage in the patient;   determining, in an implanted controller, whether nerve block is required based on the signal from the at least one sensor;   generating, from a waveform generator coupled to the implanted controller, a nerve block signal when the implanted controller indicates that the nerve block is required, the nerve block signal having a frequency of greater than 1 kHz and an amplitude of approximately 4 to 10 volts per pulse;   adjusting, by the implanted controller, the nerve block signal based on closed-loop feedback from the at least one sensor; and   applying the nerve block signal to the nerve of the patient from one or more electrodes coupled to the waveform generator, wherein the nerve block signal is adjusted as the nerve block signal is applied based on closed-loop feedback from the at least one sensor.