What is causing persistent bladder numbness during and after orgasm and after straining in a patient with a history of anal fistulotomy and pelvic‑floor hypertonicity?

Persistent Bladder Numbness After Anal Fistulotomy and Straining

This patient is experiencing iatrogenic pelvic autonomic nerve injury from anal fistulotomy surgery, compounded by pre-existing pelvic floor hypertonicity and chronic straining—the persistent bladder numbness during orgasm and urination represents sensory denervation that requires immediate urodynamic evaluation and multidisciplinary rehabilitation rather than expectant management. 1

Understanding the Mechanism

The constellation of symptoms—bladder numbness during orgasm, loss of urination sensation, and worsening after straining—points to injury of the pelvic autonomic nerves during fistulotomy surgery. 1 The fact that similar numbness occurred transiently after orgasm and straining before surgery suggests pre-existing vulnerability from pelvic floor hypertonicity. 2

Why This Happens

• Direct surgical injury: Anal fistulotomy can damage the hypogastric plexus and pelvic splanchnic nerves that provide bladder sensation, particularly when dissection extends into deeper pelvic tissues 1
• Acute straining effects: Even a single minute of straining significantly blunts anal sensation and causes measurable nerve conduction delays that normally recover within 3 minutes—but in patients with chronic straining and hypertonicity, these changes can become permanent 3
• Pelvic floor hypertonicity: Chronic muscle spasm and elevated pelvic floor tone can compress and chronically irritate pelvic autonomic nerves, making them more vulnerable to surgical trauma 4, 2

Immediate Diagnostic Workup

Urodynamic testing with cystometry must be performed to objectively document bladder sensation thresholds (first sensation, first desire, strong desire) and detrusor compliance—this provides definitive evidence of sensory denervation. 1

Additional essential evaluations include:

• Lumbosacral MRI to exclude central pathologies like cauda equina syndrome or Tarlov cysts that can mimic pelvic autonomic dysfunction 1
• Standardized sexual function questionnaires (Female Sexual Function Index or Brief Index of Sexual Functioning) to quantify deficits in arousal and orgasm, establishing a baseline for therapy 1
• Referral to urogynecology or urology for formal urodynamic evaluation to document the extent of bladder sensory loss 1

Treatment Strategy

Rehabilitation (Primary Management)

Pelvic floor physical therapy with a therapist experienced in pelvic nerve dysfunction should be initiated immediately to address muscle coordination deficits that exacerbate symptoms. 1 This is particularly critical given the pre-existing hypertonicity. 5, 2

• Bladder retraining with timed voiding every 2-3 hours is essential to prevent chronic bladder over-distension and permanent detrusor damage when sensation is blunted 1
• Perineal and pelvic floor stretching has proven highly efficacious for patients with pelvic floor spasticity, leading to improved pain, urinary stream, and sexual function 5
• Sex therapy and psychosexual counseling are essential for adapting to altered arousal patterns and exploring alternative sources of sexual satisfaction 1

Pharmacologic Limitations

No medication currently restores bladder sensory function or treats female sexual arousal disorder secondary to autonomic nerve injury—management relies entirely on behavioral strategies and physical therapy. 1

Prognosis and Expectations

Persistent bladder and sexual dysfunction beyond 6 months after pelvic surgery is strongly associated with irreversible autonomic nerve damage. 1 Given that symptoms are already constant and persistent, goals should shift toward functional adaptation rather than expecting full restoration.

Long-Term Management

• Ongoing pelvic floor physical therapy remains the primary means of improving quality of life 1
• Compensatory bladder management strategies (timed voiding) must become permanent habits 1
• Psychological support is critical for adapting to permanent changes in sexual function 1

Critical Pitfalls to Avoid

• Do not wait for spontaneous recovery: Unlike post-prostatectomy incontinence where 12-month observation is reasonable 6, 7, pelvic autonomic nerve injury requires immediate intervention to prevent secondary complications like chronic bladder over-distension 1
• Do not assume symptoms will resolve with time: The combination of surgical trauma, pre-existing hypertonicity, and chronic straining creates a high-risk scenario for permanent nerve damage 3, 2
• Do not overlook the hypertonicity component: Treating only the nerve injury without addressing the underlying pelvic floor dysfunction will result in continued nerve compression and symptom persistence 4, 5, 2