Percutaneous Nerve Evaluation Trial Time

Sacral neuromodulation (SNM) was approved by the Food and Drug Administration (FDA) for the treatment of urgency incontinence (UUI) in 1998. One of two trial phase techniques are utilized prior to placement of the implantable pulse generator (IPG) to predict a patient's success with the device: a percutaneous nerve evaluation (PNE) or a stage implantation. Patients who experience a \> 50% improvement in UUI symptoms progress to permanent implantation. PNE offers significant advantages compared to a staged implantation including a single anesthetic and operating room trip. Historically, full implantation rates are only 40-50% following PNE versus 70-90% in women who undergo a staged approach. The lower rate of progression to full implantation after PNE may be attributed to lead migration. Newer data suggest up to 90% of PNE trials lead to full implantation. The investigators hypothesize that shortening PNE trial time to 3 days from 7 days will not result in a lower proportion of PNE trials leading to SNM implantation and may offer less time for lead migration. The investigators aim to perform a multi-center, randomized trial to determine if a 3-day PNE trial is not inferior to a 7-day PNE trial with respect to rates of progression to SNM implantation.