E-Stim of Pelvic Floor Muscles

Question 1

E-stim for PF dysfunction stretches back to

Answer 1

1878

Question 2

Transvaginal stimulation for UI and IC was evaluated by:

Answer 2

Fall et all in 1977

Question 3

TENS treatment for urinary symptoms

Answer 3

@ S2-3 dermatome first documented in 1985

Question 4

MOA for PF E-stim:

Answer 4

unknown but there are theories

Question 5

MOA theories:

Answer 5

• E-stim to treat UI is thought to stimulate pelvic muscle contractions and/or modulate detrusor contractions (VanBalken 2004)

Question 6

NMES MOA

Answer 6

1) activation of pudendal nerve reflex loop (brubaker 2000)
- direct stimulation of the pudendal nerve efferent (motor) fibers, produces strong contraction of the pelvic floor muscle
- produces strong contraction of pelvic floor muscles –> High frequency (50Hz/pps) required for PFM contraction
- contraction PFM causes reflexive inhibition and relaxation of detrusor muscle

2) pudendal to pelvic nerve reflex
- less than 20 Hz
- inhibits parasympathetic fibers of the pelvic nerve causing inhibition of detrusor contractions
- turning the pelvic nerve “off”

3) pudendal to hypogastric nerve reflex:
- less than 5Hz
- excitation of sympathetic fibers of the hypogastric plexus inhibits detrusor contractions
- turning the hypogastric “on”

Question 7

Proposed TENS MOA

Answer 7

1) possible activation of endorphin pathways in the spinal cord when applied at the same sites of the spinal roots of the bladder (Bristow 1996 –> thought to inhibit reflex detrusor activity –> applied at low frequency 5-10Hz
2) direct stimulation of the sacral roots (S2-4) may activate the external urethral sphincter –> reduces detrusor activity by reflex inhibition