Anchoring units for leads of implantable electric stimulation systems and methods of making and using

A nerve stimulation lead with a distal end, a proximal end, and a longitudinal length, the nerve stimulation lead comprising:

• a plurality of electrodes disposed at the distal end;
• a plurality of terminals disposed at the proximal end;
• a plurality of conductive wires electrically coupling the plurality of electrodes electrically to the plurality of terminals;
• and
• at least one anchoring unit disposed on the nerve stimulation lead, the at least one anchoring unit comprising an expandable tip disposed on the nerve stimulation lead distal to the plurality of electrodes, wherein the expandable tip is configured and arranged to remain undeployed through implantation of the lead and to be deployed after implantation of the lead by causing the expandable tip to expand in diameter.

A nerve stimulation lead with a distal end, a proximal end, and a longitudinal length, the nerve stimulation lead comprising:

• a plurality of electrodes disposed at the distal end;
• a plurality of terminals disposed at the proximal end;
• a plurality of conductive wires electrically coupling the plurality of electrodes electrically to the plurality of terminals;
• and
• at least one anchoring unit disposed on the nerve stimulation lead, the at least one anchoring unit comprising an inner ring, an outer ring defining at least one cutout, and at least one anchoring element that is attached to the inner ring and configured and arranged to rotate out from the at least one cutout of the outer ring when one of the inner ring and at least one anchoring element are rotated in a first direction relative to the outer ring.