Sacral Neuromodulation for Chronic Pelvic Pain

The change in pain score using a 10-point Visual Analogue Scale (VAS) from 2-10 weeks.

The VAS is a validated tool to determine patient perceived pain. VAS is scored from 0-10, where 0 = no pain and 10 = worst possible pain. The value at Visit 4 (10 weeks post-implant) minus the value at Visit 2 (baseline, 2 weeks post-implant) will be used to calculate change. Negative numbers indicate an improvement in pain, and positive numbers indicate a worsening pain

The change in central sensitization score over 13 months

Change in central sensitization will be assessed using the temporal summation test using the TSA2 AIR system. Temporal summation is considered a manifestation of central sensitization and can be assessed using thermal modalities. It is measured as the magnitude of positive slope of the line fitted to the series of 10 stimuli at the target temperature. A larger slope reflects a higher degree of central sensitization. The central sensitization slope at each treatment visit (visits 3 through 8) minus the slope at visit 2 (baseline, 2 weeks post-implementation) will be recorded and analyzed. A positive number reflects more central sensitization, and a negative number reflects less central sensitization.

Change in pelvic floor pain using a 10-point VAS pain score.

A trained provider will palpate all 4 quadrants of the pelvis, while recording pain scores for each quadrant. The VAS is a validated questionnaire that assesses pain on a scale from 0 = no pain to 10 = worst possible pain. The subject will provide a pain score from 0 - 10 for each of the 4 quadrants assessed. The average pain score of the 4 quadrants is then calculated. The average pain score ranges from 0 to 10. The difference in value from visit 2 (baseline, 2 weeks post implant) minus visit 8 (an average of 13 months post implant) is calculated. A positive number indicates improvement of symptoms. A negative number indicates worsening of symptoms.

Change in severity of overactive bladder symptoms.

The change in OAB symptoms between baseline (visit 2) and subsequent study visits will be assessed using the 6-question Overactive Bladder Questionnaire Short Form (OABq). OABq is a well-established questionnaire used to assess severity of OAB symptoms. The OAB-Q Short Form (SF) consists of two scales assessing symptom bother and health-related quality of life (HR-QOL) in patients with OAB. Each question is rated on a 6 point scale with 1 = Not at all and 6 = A very great deal. Scores can range from 0 to 100, with higher scores indicating more severe symptoms. The change is calculated from the baseline (visit 2, 2 weeks post-implant) minus the value at visit 8 (an average of 13 months post-implant). A positive number indicates improvement of symptoms. A negative number indicates worsening of symptoms.

Change in Female Sexual Function

The Female Sexual Function Index (FSFI) is a 19-question questionnaire evaluating female sexual health in several domains: libido, arousal, lubrication, orgasm, satisfaction, and sexual pain. Each subdomain is scored separately, and the total score calculated. Change in FSFI score will be assessed between baseline (visit 2, 2 weeks-post implant) and visit 8 (an average of 13 months post-implant). A lower FSFI score is equivalent to a higher degree of sexual dysfunction. Scores range from 0 to 36. The change value is calculated from visit 8 (approximately 13 months post-implant) minus visit 2 (baseline, 2 weeks post-implant). A positive number indicates improvement of symptoms. A negative number indicates worsening of symptoms.