Patent ID: 11877860
Assignee: NUVASIVE, INC.
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 16:
17. A method of neurophysiologic assessment during a spinal surgical procedure, said method comprising the steps of:
establishing an operative corridor to a surgical target site inferior to spinal level L1-2 along a lateral, trans-psoas path of a patient;
before establishing the operative corridor, delivering a first transcutaneous, transabdominal stimulation signal by a neurophysiologic monitoring system, via a single cathode electrode adhered to the midline of the back of the patient at spinal level L1-2 and a single anode electrode adhered to the patient's anterior abdominal midline, wherein said first transcutaneous, trans-abdominal stimulation signal is of sufficient intensity to evoke a response in a muscle located inferior to said surgical target site; and
recording a first neuromuscular response data set of said muscle located inferior to said surgical target site based on the delivery of said first transcutaneous, trans-abdominal stimulation signal, wherein said first neuromuscular response data set includes a stimulation intensity of the delivered first transcutaneous, trans-abdominal stimulation signal and a stimulation intensity of the signal received at said muscle in response to said first transcutaneous, transabdominal stimulation signal, wherein the stimulation intensity of the first delivered signal and the first received signal are recorded in said neurophysiologic monitoring system via one or more electrodes inferior to the surgical site;
delivering, periodically during the spinal surgical procedure, a second transcutaneous, trans-abdominal stimulation signal by the neurophysiologic monitoring system, via the cathode electrode and the anode electrode, to the lumbar motor neural pathways superior and inferior to the surgical target site of said spinal surgical procedure during establishment of the operative corridor to the surgical target site;
recording a second neuromuscular response data set of said muscle located inferior to said surgical target site based on the delivery of said second transcutaneous, trans-abdominal stimulation signal, wherein said second neuromuscular response data set includes a stimulation intensity of the delivered second transcutaneous, trans-abdominal stimulation signal and a stimulation intensity of the signal received at said muscle in response to said second transcutaneous, trans-abdominal stimulation signal, and wherein the stimulation intensity of the second delivered signal and the second received signal are recorded in said neurophysiologic monitoring system via the one or more electrodes;
wherein the neurophysiologic monitoring system has a selectable alert testing mode and a selectable threshold testing mode, wherein a control unit in alert testing mode evaluates the second neuromuscular response data for the presence of a response to said second transcutaneous, trans-abdominal stimulation signal, and wherein the control unit in the threshold testing mode detects changes in stimulation intensity between the first and second neuromuscular response data sets;
monitoring changes to health or status of one or more nerves during the spinal surgical procedure by detecting changes in stimulation intensity of the one or more nerves using the first and second neuromuscular response data sets; and
automatically determining, by the neurophysiologic monitoring system, the health or status of the one or more nerves during the spinal surgical procedure based on at least one of the alert testing mode and threshold testing mode, wherein an alert is provided in the alert testing mode if no response is detected to said second transcutaneous, trans-abdominal stimulation signal, and wherein an alert is provided in the threshold testing mode if the difference between said stimulation intensity of said first and second responses are not within a pre-determined amount.