Login to Access Video or Poster Abstract: MP26-14
Sources of Funding: none

Introduction

To aid and clarify the approach for percutaneous lead placement for permanent implantation of tibial nerve stimulation lead electrode.

Methods

A cadaver model was developed to guide delivery of permanently implanted tibial nerve leads using bony landmarks, ultrasound and fluoroscopic imaging in below the knee cadaver legs. The tibial artery was identified proximally and a guide wire placed. The tibial nerve leads were placed percutaneously with a standard lead introducer. Both antegrade (proximal to distal) and retrograde approaches (distal to proximal) were explored. Both approaches were evaluated real time with ultrasound (transverse and longitudinal) and fluoroscopy (lateral and anterior-posterior). Then the cadaver legs were dissected and lead placement was evaluated with respect to depth and orientation to the nerve.

Results

Ultrasound identified the wire in the artery in both transverse and longitudinal planes, and the nerve posterior. Flouroscopy, lateral and anterior-posterior, was effective in identifing the vector of lead placement, whether crossing the tibial nerve vs. placement more parallel to the nerve. The antegrade approach was modified by migrating more proximally up the lower leg, to try to achieve a more parallel vector of lead placment with the nerve. However, antegrade approaches were always crossing the tibial nerve and went deep to the nerve, with only 1-2 electrodes in close proximity to the nerve. The retrograde approach, starting at the level of the medial malleolus, about 1 finger breadth behind (in general about 1/3 the distance from the medial malleolus to Achilles tendon) was easy and effective in placing the lead parallel to the nerve with 3-4 electrodes in close proximity to the nerve.

Conclusions

We report a novel, safe retrograde method of percutaneous lead placement parallel to the tibial nerve, avoiding key vascular structures. The retrograde approach, starting posterior to the medial malleolus, was easier and reproducibly placed a more parallel lead that may optimize tibial nerve stimulation. Ultrasound was effective in localizing the tibial artery to aid orientation and depth of placement of the stimulation lead and maximize safety. This minimally invasive retrograde percutaneous approach can place a chronic tibial nerve stimulation lead in the physicians office under local anesthesia.

Funding

none