Chinese article claims sacral nerve stimulation cured 19/32 and improved 12/32 cases.
Zhonghua Wei Chang Wai Ke Za Zhi. 2012 Dec;15(12):1236-9.
Sacral nerve stimulation treatment in functional anorectal pain.
Wang ZM, Xin XZ, Duan MM. abstract here
Article in Chinese so not much to add. Sacral nerve stimulation has also been used for rectal incontinence:
Dis Colon Rectum. 2011 Sep;54(9):1065-75.
Long-term efficacy and safety of sacral nerve stimulation for fecal incontinence.
Mellgren A, Wexner SD, Coller JA, Devroede G, Lerew DR, Madoff RD, Hull T free article here
“At 3 years follow-up, 86% of patients (P > .0001) reported >50% reduction in the number of incontinent episodes per week compared with baseline and the number of incontinent episodes per week decreased from a mean of 9.4 at baseline to 1.7. Perfect continence was achieved in 40% of subjects .”
It has also been used for intractible constipation:
Br J Surg. 2013 Jan;100(2):174-81.
Sacral nerve stimulation for constipation.
Thomas GP, Dudding TC, Rahbour G, Nicholls RJ, Vaizey CJ. abstract here
“Up to 87 per cent showed an improvement in symptoms at a median follow-up of 28 months”
For treatment of pain, there have been case studies and one Italian trial:
Dis Colon Rectum. 2009 Mar;52(3):456-62.
Is sacral nerve stimulation an effective treatment for chronic idiopathic anal pain?
Falletto E, Masin A, Lolli P, Villani R, Ganio E, Ripetti V, Infantino A, Staziv abstract here
- 12 hopeless cases not helped by drugs or rehab
- “After a mean follow-up of 15 (range, 3-80) months, visual analog pain scores had significantly improved (from 8.2 +/- 1.7 to 2.2 +/- 1.3, P < 0.001).”