Surgical instruments with electrically isolated actuation members, related devices, and related methods

An actuation member for transmitting force from a drive mechanism to an end effector of a surgical instrument, the actuation member having a length extending from a proximal end to a distal end, the actuation member comprising:

• an electrically conductive distal flexible portion extending proximally from the distal end of the actuation member and configured to be operably coupled with the end effector of the surgical instrument;
• an electrically conductive proximal rod portion connected to and extending proximally from the distal flexible portion, the proximal rod portion being configured to be operably coupled to the drive mechanism, the proximal rod portion comprising a blind bore in which a proximal end portion of the distal flexible portion is received, the distal flexible portion in electrically conductive communication with the electrically conductive proximal rod portion, and the proximal rod portion having a solid cross-section proximally of a terminating end of the blind bore;
• a first electrically insulating material surrounding at least some of a length of the distal flexible portion that is not received in the blind bore;
• a second electrically insulating material overlapping the first electrically insulating material and surrounding at least some of a length of the proximal rod portion from a location where the proximal rod portion connects to the distal flexible portion and to a location where the proximal rod portion is solid;
• an electrically insulating sleeve overlapping at least a portion of the second electrically insulating material and extending proximally past the second electrically insulating material along a length of the proximal rod portion that is solid;
• and
• an electrically insulating cylinder overlapping at least a portion of the electrically insulating sleeve and positioned over a proximal end portion of the proximal rod portion.