Risk of Irreversible Autonomic Nerve Damage from Anorectal Surgery
These superficial anorectal procedures (fistulotomy, lateral sphincterotomy, fissurectomy, and hemorrhoidectomy) do NOT cause irreversible autonomic nerve damage affecting sexual or ejaculatory function, as they operate exclusively on the anal sphincter muscles at the anal canal level and do not approach the deep pelvic autonomic nerves located several centimeters away. 1
Anatomical Safety Considerations
The deep pelvic autonomic nerves responsible for sexual and ejaculatory function—including the hypogastric plexus and pelvic splanchnic nerves—are positioned several centimeters away from the surgical field of these superficial anorectal procedures. 1 These operations involve only the anal sphincter muscles at the anal canal level and do not extend into the deep pelvis where autonomic nerve injury could occur. 1
Actual Documented Complications
Lateral Internal Sphincterotomy
The primary concern with lateral sphincterotomy is fecal incontinence, not autonomic nerve damage. 2
- Incontinence occurs in 2-12% of patients after hemorrhoidectomy with sphincter manipulation 2
- Long-term studies show 45% of patients experience some degree of fecal incontinence at some point postoperatively, though most episodes are minor and transient 3
- By 5+ years after surgery, only 6% report incontinence to flatus, 8% have minor soiling, and 1% experience loss of solid stool 3
- Only 3% of patients report that incontinence ever affected their quality of life 3
- Women experience higher incontinence rates (53.4%) compared to men (33.3%) 3
Post-Surgical Sensory Changes
When patients develop altered sensations or sexual discomfort after lateral sphincterotomy, these are typically neuropathic pain and dysesthesia rather than structural sphincter or autonomic nerve damage. 1
Pelvic floor muscle tension and protective guarding patterns can develop during the painful fissure period and persist after surgery. 1 These myofascial issues—not nerve injury—are the usual cause of post-surgical discomfort.
Fissurectomy
Both open and closed lateral internal sphincterotomy are superior to fissurectomy in terms of healing rate, but fissurectomy avoids sphincter injury entirely. 2 However, one study found higher incontinence rates with fissurectomy compared to lateral sphincterotomy, though this finding is inconsistent with the procedure's sphincter-sparing nature. 4, 5
Hemorrhoidectomy
- Incontinence occurs in 2-12% of patients as an immediate postoperative complication 2
- Sphincter defects documented by ultrasonography and manometry occur in up to 12% of patients 2
- Manual dilatation of the anus is absolutely contraindicated due to 30% temporary and 10% permanent incontinence rates 6
Fistulotomy
For low fistulas in Crohn's disease patients without rectal inflammation, fistulotomy has greater healing rates, but cutting setons carry a 57% risk of incontinence due to forced sphincter transection and are strongly discouraged. 2
Management of Post-Surgical Sensory Symptoms
If patients develop altered sensations or sexual dysfunction after lateral sphincterotomy, initiate specialized pelvic floor physical therapy 2-3 times weekly. 1, 6
Treatment should focus on:
- Internal and external myofascial release 1, 6
- Gradual desensitization exercises 1, 6
- Muscle coordination retraining 1, 6
For neuropathic pain, apply topical lidocaine 5% ointment to affected areas. 1
Symptoms typically improve significantly over 6-12 months with appropriate therapy, and additional surgical interventions should not be pursued. 6
Safer Alternative for Chronic Anal Fissure
Botulinum toxin injection achieves 75-95% cure rates for chronic anal fissures with no risk of permanent incontinence or sexual dysfunction. 2, 1, 6 This should be considered after 8 weeks of failed topical therapy before proceeding to sphincterotomy. 2, 6
Critical Pitfalls to Avoid
- Never attribute post-surgical sexual or ejaculatory dysfunction to these procedures as autonomic nerve injury—the anatomy does not support this mechanism 1
- Recognize that persistent pain or discomfort is typically myofascial/neuropathic rather than mechanical sphincter failure, requiring physical therapy rather than surgical revision 6
- Avoid excessive retraction and extensive anal canal dilation during hemorrhoidectomy, as these are responsible for sphincter injury and incontinence 2
- Never add lateral internal sphincterotomy as an adjunct to hemorrhoidectomy—studies show this increases incontinence rather than reducing it 2