In a patient post‑fistulotomy (≈30% internal/external sphincter resected) with reduced rectal tightness and diminished orgasmic pleasure, does loss of baseline resting anal pressure indicate loss of rectal arousal?

Loss of Baseline Resting Anal Pressure Does Not Indicate Loss of Rectal Arousal

The reduction in baseline resting anal pressure after fistulotomy reflects permanent internal anal sphincter (IAS) damage and loss of smooth-muscle tone—not a loss of rectal sensory arousal or sexual function. The IAS generates passive resting tone through involuntary smooth muscle contraction and has no role in sexual sensation or orgasmic pleasure 1, 2, 3.

Understanding the Physiology: IAS vs. Sensory Function

What Baseline Resting Pressure Actually Measures

• Baseline (resting) anal pressure is generated almost entirely by the internal anal sphincter (IAS), an involuntary smooth-muscle structure that maintains passive continence at rest 1, 3.

• After fistulotomy with 30% sphincter resection, resting pressure drops significantly and permanently—studies show a decline from baseline values of ~138 mmHg to ~86 mmHg at 1 month, with partial recovery to ~110 mmHg at 12 months but never returning to pre-surgical levels 3.

• This pressure loss reflects structural sphincter defects visible on endoanal ultrasound, with IAS defects increasing from 30.8% to 74.3% of patients post-fistulotomy 2.

Why Pressure Loss Does Not Equal Arousal Loss

• The IAS is composed of smooth muscle with no sensory nerve endings for sexual arousal; it functions purely for passive continence through tonic contraction 1, 3.

• Rectal sensory arousal and orgasmic pleasure depend on:

  • Intact sensory nerve endings in the rectal mucosa and perianal skin
  • Pudendal nerve function (which was not affected by pudendal nerve latency changes in fistulotomy studies) 2
  • Pelvic floor muscle coordination and voluntary external anal sphincter (EAS) function 4

• Studies of fistulotomy show that pudendal nerve terminal motor latency does not change postoperatively, indicating preserved neurologic pathways for sensation 2.

The Real Problem: Pelvic Floor Dysfunction, Not Pressure Loss

What Is Actually Causing Your Symptoms

• Your diminished orgasmic pleasure and altered rectal sensation are caused by pelvic floor muscle tension and protective guarding patterns that developed during the painful pre-surgical period and persist after fistulotomy 4.

• This is a myofascial and neuropathic problem, not a sphincter-tone problem 4, 5.

• The "reduced rectal tightness" you describe reflects loss of passive IAS tone (which is permanent after 30% resection) but does not explain the sensory changes, which stem from muscle hypertonicity and dyscoordination 4, 1, 2.

Evidence-Based Treatment Algorithm

Step 1: Initiate Pelvic Floor Physical Therapy (Primary Treatment)

• Begin pelvic floor physical therapy 2–3 times weekly with:

  • Internal and external myofascial release
  • Gradual desensitization exercises
  • Muscle coordination retraining
  • Warm sitz baths 2–3 times daily 4, 5

• This addresses the root cause: pelvic floor muscle tension and altered sensory processing, not sphincter tone 4.

Step 2: Add Neuropathic Pain Management

• Apply topical lidocaine 5% ointment to affected areas for neuropathic pain control 4.

• Avoid all sphincter-relaxing medications (calcium-channel blocker creams, nitroglycerin, botulinum toxin), as these target sphincter hypertonia—a problem you do not have—and may worsen continence in the setting of existing sphincter damage 5.

Step 3: Set Realistic Expectations

• Dysesthesia and altered sensations typically improve significantly over 6–12 months with appropriate pelvic floor therapy and neuropathic pain management 4.

• The reduced baseline resting pressure is permanent due to structural sphincter loss, but this does not prevent recovery of sexual function and sensory pleasure 1, 2, 3.

Critical Pitfalls to Avoid

Do Not Pursue Additional Surgical Interventions

• No further surgery should be performed to address your sensory symptoms, as additional sphincter manipulation would likely worsen the neuropathic component rather than improve it 4.

• Manual anal dilatation is absolutely contraindicated, carrying a 30% temporary and 10% permanent incontinence rate 4, 6.

Do Not Misinterpret Manometry Results

• Low resting pressure on manometry does not diagnose or explain loss of arousal; it simply confirms the expected structural consequence of sphincter resection 1, 2, 3.

• One older study suggested that the therapeutic effect of sphincterotomy might be due to anatomic widening rather than pressure reduction, further supporting that pressure itself is not the key variable for sensory function 7.

Why This Distinction Matters Clinically

• Baseline resting pressure = IAS smooth-muscle tone = passive continence function 1, 3

• Rectal arousal and orgasmic pleasure = sensory nerve endings + pelvic floor muscle coordination + pudendal nerve function 4, 2

• These are separate physiologic systems that happen to coexist in the same anatomic region but do not causally depend on one another 4, 1, 2.

• Your symptoms require pelvic floor rehabilitation and neuropathic pain management, not interventions targeting sphincter tone 4, 5.