Transcutaneous Neuromodulation at Posterior Tibial Nerve and ST36 for Chronic Constipation

Abstract

The aims of this study were to investigate the effects and possible mechanisms of transcutaneous neuromodulation (TN) in patients with chronic constipation. Twelve patients were recruited. The treatment consisted of 2-week TN and 2-week sham-TN which was performed in a crossover design. Bowel habit diary, Patient Assessment of Constipation Symptom (PAC-SYM), Patient Assessment of Constipation Quality of Life (PAC-QOL), and anorectal motility were evaluated. Electrocardiogram was recorded for the assessment of autonomic function during acute TN therapy. It was found that (1) TN improved the frequency of spontaneous defecation. After 2-week TN therapy, 83% patients had more than 3 times bowel movements per week which was significantly different from sham-TN (P = 0.01). (2) TN improved PAC-SYM and PAC-QOL scores (P < 0.001, resp.). (3) TN significantly decreased the threshold volume to elicit RAIR (P < 0.05), ameliorated rectal sensory threshold (P = 0.04), and maximum tolerance (P = 0.04). (4) TN, but not sham-TN, increased the vagal activity (P = 0.01 versus baseline) and decreased the sympathetic activity (P = 0.01, versus baseline). It was concluded that needleless TN at posterior tibial nerve and ST36 using a watch-size stimulator is effective in chronic constipation, and the effect was possibly mediated via the autonomic mechanism.

Ameliorating effects and autonomic mechanisms of needle‐less transcutaneous electrical stimulation atST36 on stress‐induced impairment in gastric slow waves

“…A watch‐size digital stimulator (SNM‐FDC01, Ningbo MedKinetic Inc., Ningbo, China) was built and used to deliver electrical stimulation via these two electrodes using trains of pulses as follows: train on‐time of 2 s and off‐time of 3 s, pulse width of 0.5 ms, pulse frequency of 25 Hz, and current intensity at the maximum level tolerated by the subject (the subject sensed stimulation but could tolerate the test without distraction). This set of parameters was previously shown to improve gastric motility in our lab . For transcutaneous electrical stimulation, the actual current delivered into the acupoint is dependent on the impedance between the electrode and acupoint; whereas, the impedance varies among different subjects.…”

“…To make the stimulation more uniform, we have chosen to use the sensation of the subject to set the strength of the TEA. This method has been used in a number of previous studies …”

Effectiveness of percutaneous tibial nerve stimulation in managing refractory constipation

“…The idea that a similar benefit can be achieved in constipation is supported by the findings of two studies using transcutaneous tibial nerve stimulation, both of which reported symptomatic improvement in patients with constipation . In the first study PTNS was given for 1 h twice daily for 2 weeks and in the second study twice weekly for 30 min for 6 weeks . Similar accounts of improved results with an increase in the stimulation frequency have also been reported with gastric pacing for gastroparesis and deep brain stimulation for Parkinson's disease .…”

Electroacupuncture treatments for gut motility disorders

“…Without the need to come to the hospital, the compliance of the TEA is substantially increased. Possibly attributed to these above factors, TEA was reported to be effective in treating GERD, functional dyspepsia, and functional constipation in a few small‐scale single‐center studies . The disadvantage of delivering electrical current superficially to the skin rather than deep into the acupuncture point seemed to be compensated by more frequent administrations of TEA.…”

“…Home‐based TEA has also been reported effective in increasing complete spontaneous bowel movement and reducing constipation symptoms in patients with functional constipation in a pilot study. Mechanistically, TEA was found to improve sympathovagal balance, that is, suppression of sympathetic over‐activity and enhancement of vagal tone . Further large‐scale studies are needed to establish the clinical utilization of TEA for treating chronic functional constipation.…”