Failed Sacral Neuromodulation

Abstract

In Brief Objective: The objective of this study was to demonstrate the diagnosis of pudendal neuropathy in 8 consecutive female patients presenting in 2004 with chronic pelvic pain unsuccessfully treated using sacral nerve root stimulators. Clinical symptom history, physical examination, and neurophysiological tests confirmed pudendal neuropathy as a cause of their pelvic pain. Methods: Eight women with previous placement of a sacral nerve root stimulation device for chronic pelvic pain presented to the Center for Urologic and Pelvic Pain between January and August 2004. In each, the device was unsuccessful in controlling their pain. Focused symptom history suggested pudendal neuralgia, specifically pelvic pain aggravated by sitting, reduced by standing or recumbency, and relieved by sitting on a toilet seat. Tests included sensory examination, warm detection threshold, and pudendal nerve terminal motor latency test. Results: Sensory examination, warm detection threshold testing, and pudendal nerve terminal motor latency tests confirmed the clinical symptoms of pudendal neuropathy in all 8 subjects. Conclusions: Patients with chronic pelvic pain should be evaluated neurologically to identify or rule out pudendal neuropathy before implantation of a sacral nerve root stimulator is considered. If test results are abnormal, then stimulation is not likely to be successful. Patients with chronic pelvic pain that fails to respond to neuromodulation should be evaluated for pudendal neuropathy. Eight women with chronic pain had previously received sacral nerve root stimulators as treatment. Because of failure of pain control they sought further evaluation. Symptoms were typical of pudendal neuralgia and evaluation, including physical examination, warm detection threshold testing and pudendal nerve terminal motor latency tests confirmed pudendal neuropathy.