Fig. 1

Lead placement on spinal cord and electrophysiology recording examples. A cartoon demonstration of two Octrode™ leads placed in series on the spinal cord with partial laminectomies starting on L1 and the 5 thoracic segments rostral which can be seen in the animated spinal column. B X-ray image showing the placement of two leads with the lowest contact (8) located at the same level as the lowest rib bone (marked with arrow and outlined with dotted lines). Electrode contracts 7 and 8 on the first lead were used as stimulation electrodes, unless otherwise stated. The second lead with contacts 9 to 16 was placed more rostrally. C Example of ESR from four different channels along the electrode arrays. In each subplot, the grey background is the aggregation of 300 individual recordings, and the blue trace is the median waveform of these consecutive individual trials. The two dashed lines in each subplot indicate the end of stimulation and the biggest negative peak in the ECAP component in ESR, respectively. The arrowed line in the top subplot shows the measured latency of the ECAP component recorded on Channel 9