What could be causing a patient's decreased libido and sexual sensation after a hemorrhoidectomy and three subsequent surgeries for a fissure, given that they had normal sexual function prior to the surgeries?

Sexual Dysfunction After Anorectal Surgery

The most likely cause of persistent decreased libido and sexual sensation after hemorrhoidectomy and subsequent fissure surgeries is pudendal nerve injury from the surgical procedures, particularly if posterior mucosal anoplasty or internal sphincterotomy was performed. This represents a recognized but underreported complication of anorectal surgery that can result in permanent changes to genital sensation and sexual function.

Mechanism of Injury

Pudendal nerve damage during pelvic floor surgery is the primary mechanism for post-surgical sexual dysfunction in this clinical scenario:

• The pudendal nerve provides sensory innervation to the external genitalia, perineum, and distal anal canal, and surgical dissection in the posterior anal region can directly injure these nerve branches 1
• Internal sphincterotomy, commonly performed with fissure repair, carries risk of nerve injury when the dissection extends beyond the intersphincteric plane 2
• The Leopold Bellan procedure (posterior mucosal anoplasty combined with hemorrhoidectomy) involves more extensive posterior dissection that increases risk of neurovascular damage 2, 3

Clinical Evaluation

Perform a focused neurological and anatomical assessment to document the extent of dysfunction:

• Test perineal sensation bilaterally using light touch and pinprick to map areas of sensory loss 4
• Assess for saddle anesthesia, which would indicate more extensive cauda equina involvement requiring urgent MRI 4
• Evaluate anal sphincter tone via digital rectal examination and check the bulbocavernosus reflex 4
• Document bladder and bowel function, as new urinary retention or bilateral lower extremity symptoms would necessitate emergency imaging to rule out cauda equina syndrome 4
• Perform speculum examination in female patients to assess for vaginal stenosis, mucosal changes, or anatomic distortion from surgical scarring 1

Screen for contributing psychosocial factors that commonly compound physical dysfunction:

• Assess for depression and anxiety using validated screening tools, as these are prevalent after pelvic surgery and independently impair sexual function 5
• Identify medications that may contribute, particularly narcotics for chronic pain and SSRIs if prescribed for mood symptoms 5
• Evaluate relationship dynamics and partner health status, as these significantly impact sexual activity 5

Diagnostic Workup

If bilateral radiculopathy, new bladder symptoms, or progressive neurological deficits are present, obtain emergency MRI of the lumbar spine to exclude cauda equina syndrome:

• MRI with and without IV contrast is mandatory, including T1-weighted sequences before and after gadolinium administration 6
• Cauda equina syndrome presents with bilateral leg symptoms, saddle anesthesia (90% sensitivity for urinary retention), and progressive neurological deficits 4
• Emergency surgical decompression within 12 hours provides the best outcomes if mechanical compression is identified 6, 4

For isolated sexual dysfunction without red flag symptoms, the workup focuses on documenting the extent of dysfunction:

• Use the Female Sexual Function Index (validated in surgical populations) to quantify arousal, lubrication, orgasm, pain, and satisfaction domains 5
• Physical examination should document points of tenderness, vaginal atrophy, and anatomic changes from surgery 5
• Consider pelvic floor physical therapy evaluation to assess for myofascial pain and pelvic floor dysfunction 1

Management Approach

There is no definitive treatment to reverse established pudendal nerve injury, but symptomatic management can improve quality of life:

• Refer to pelvic floor physical therapy for desensitization techniques, dilator therapy if stenosis is present, and treatment of myofascial pain 1
• Consider topical estrogen therapy in postmenopausal women or those with vaginal atrophy to improve tissue health and reduce dyspareunia 5
• Prescribe vaginal lubricants and moisturizers for symptomatic relief of dryness and friction-related discomfort 5
• Refer to sex therapy or counseling to address psychological components, relationship issues, and adaptive strategies for intimacy 5

Address modifiable contributing factors aggressively:

• Optimize treatment of depression and anxiety, as these significantly impair sexual function independent of nerve injury 5
• Review and modify medications that impair sexual function, particularly switching from SSRIs to bupropion if antidepressants are needed 5
• Manage chronic pain with non-narcotic approaches when possible, as opioids suppress libido and sexual function 5

Prognosis and Counseling

Set realistic expectations about recovery, as nerve injury from surgery may result in permanent changes:

• The 1-year outcome data from hemorrhoidectomy shows that while anal symptoms improve dramatically, de novo sexual dysfunction can persist 3
• Approximately 40% of sexually active patients experience persistent sexual dysfunction after pelvic surgery, with ostomates and those undergoing more extensive procedures at highest risk 7
• Recovery of sensation is more likely if some perineal sensation remains, but complete sensory loss typically indicates irreversible injury 4

Common Pitfalls to Avoid

• Do not dismiss the patient's temporal correlation between surgery and symptoms - the timing strongly suggests iatrogenic injury rather than coincidental age-related changes 1, 7
• Do not delay MRI if any bilateral symptoms, bladder dysfunction, or saddle anesthesia are present - these are red flags for cauda equina syndrome requiring emergency intervention 6, 4
• Do not attribute all symptoms to psychological factors - while depression and anxiety contribute, the physical nerve injury is the primary driver in this scenario 5
• Do not perform repeat surgical interventions without clear anatomic indication - additional surgery risks further nerve damage and worsening of symptoms 1
• Do not overlook partner involvement in treatment - sexual dysfunction affects both individuals and couples-based interventions improve outcomes 5