Fig. 4
![Fig. 4](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs13018-016-0506-7/MediaObjects/13018_2016_506_Fig4_HTML.gif)
An electrical lead connected to a portable stimulator (SPR Therapeutics, LLC, Cleveland, OH; illustration used with permission from Brian M. Ilfeld, MD, MS)
An electrical lead connected to a portable stimulator (SPR Therapeutics, LLC, Cleveland, OH; illustration used with permission from Brian M. Ilfeld, MD, MS)