SUFU 2019: 12 Year Single Center Retrospective Review of Risk Factors and Rate of Tined Lead Breakage During Sacral Neuromodulation Lead Explant

Miami, FL (UroToday.com) The tined lead for use with the InterStim sacral neuromodulation (SNM) device was first introduced in 2002, to electrically stimulate the sacral nerve and potentially result in improved bowel and bladder symptoms.  In 2010, the manufacturer of the device (Medtronic, MN) has estimated the risk of lead breakage at the time of removal to be about 1%. In cases where the lead is to be removed, the manufacturer has recommended removal from an incision over the sacrum.

However, there have been no large published studies to date to estimate the rate of lead breakage during explantation, although previous reports from the Cleveland Clinic has estimated an 18% rate of lead breakage based on 5-year data.

Jessica Rueb, MD, from the Cleveland Clinic reported her institution’s experience with lead breakage based on a retrospective review of lead explants from 2006 to 2018. Exclusion criteria included patients with non-tined leads, missing information, explants due to infection, or a history of a failed stage 1 procedure.

283 patients met study eligibility requirements during the study timeframe. Patients were predominantly female (93%) with a median age of 52 years (range 42-65 years), median BMI of 28, and median time since implantation of 2.4 years. 15% of explanations at their institution had been implanted at an outside hospital.

23/283 (8.1%) had lead breakage during lead removal. Various factors were assessed comparing those with a lead removed intact and those that had lead breakage during removal. On univariate analysis, clinical factors that were predictive of lead breakage included male gender, history of diabetes, time since implantation, and loss of efficacy prior to lead explant. However, on multivariate analysis, only gender (OR 8.2 95% CI 2.6-25.5) and time since implantation (OR 0.675 95% CI 0.555-0.821) remained significant. There was a 67% increased risk of lead breakage if time since implant was 4.5 vs 2.2 years and an 8.2 times higher risk of lead breakage in males.

Various surgical techniques for lead removal at their institution include lead removal from the incision over the sacral foramen, lead removal from the IPG incision, and lead removal from incision over the sacral foramen with the use of a straight stylet. All of the incidents of lead breakage occurred when the lead was removed from an incision over the sacral foramen, but this did not result in any statistical significance.

The authors concluded that the rate of lead breakage is higher than estimated by the manufacturer of the Interstim device (8.1% versus 1%), and that the strongest predictor of lead breakage was the time interval since lead implant. Furthermore, removing the lead from an incision over the sacral foramen, as suggested by the manufacturer, did not seem to be protective.


Presented by: B Jessica Rueb, MD, Cleveland Clinic, Cleveland, Ohio

Written by: Judy Choi, MD, Assistant Professor, Department of Urology, University of California, Irvine @judymchoi at the Society of Urodynamics, Female Pelvic Medicine & Urogenital Reconstruction Winter Meeting, SUFU 2019, February 26 - March 2, 2019, Miami, Florida