Sensory‑Seeking Compulsion with Pelvic‑Floor Dyssynergia and Rectal Hyposensitivity Following Hemorrhoidectomy
This patient has a combined disorder of dyssynergic defecation with rectal sensory impairment, complicated by obsessive‑compulsive disorder manifesting as compulsive body‑scanning and sensory‑seeking behaviors; the primary work‑up is anorectal manometry with sensory threshold testing, followed by biofeedback therapy targeting both pelvic‑floor coordination and sensory retraining, with concurrent psychiatric management of the OCD component. 1
Understanding the Clinical Picture
The Core Problem: Loss of Proprioceptive Feedback
Hemorrhoidectomy can cause denervation and devascularization of the anorectum, leading to persistent voiding dysfunction, pain, and altered sensation—the patient's "missing" deep rectal sensation is a recognized functional complication of pelvic‑floor surgery. 2
Rectal sensory impairment (hyposensitivity) is defined by elevated thresholds for detecting rectal distension; patients may not perceive the urge to defecate until the rectum is markedly distended, and they often lack awareness of rectal filling. 1
The concurrent loss of fine bladder‑filling sensation suggests shared pelvic‑floor neuromuscular dysfunction, because both urinary and defecatory systems rely on common sensory pathways. 1
The patient's conscious tensing to "search for grounding feelings" represents a maladaptive compensatory strategy for the absent proprioceptive feedback that was previously used for arousal and sleep regulation. 1
The OCD Component: Compulsive Body‑Scanning
OCD is characterized by time‑consuming, distressing compulsions that the individual feels driven to perform; in this case, the compulsion is repetitive body‑scanning and tensing to locate a sensation that no longer exists. 3
The patient's behavior meets DSM‑5 criteria for OCD: the urge to search for the sensation is intrusive and unwanted (obsession), the conscious tensing is a repetitive mental/physical act performed in response to that urge (compulsion), and the behavior is time‑consuming and causes clinically significant distress. 2
Reassurance‑seeking through body‑scanning is a recognized OCD compulsion that provides only short‑lived relief and perpetuates the obsessive cycle. 4
The fact that normal bowel movements temporarily relieve distress does not exclude OCD—it indicates that the patient experiences transient sensory feedback during defecation, which briefly satisfies the compulsive need for proprioceptive grounding. 1
Diagnostic Work‑Up
First‑Line Testing: Anorectal Manometry with Sensory Assessment
Anorectal manometry combined with the balloon‑expulsion test is the essential first‑line evaluation for suspected defecatory disorders and sensory impairment. 1
The International Anorectal Physiology Working Group (IAPWG) protocol measures both motor function and rectal sensory thresholds using stepwise graded balloon distension during manometry. 1
Expected findings in this patient:
- Elevated sensory thresholds: first‑sensation > 60 mL and urge‑to‑defecate > 120 mL, confirming rectal hyposensitivity. 1
- Possible paradoxical anal contraction or < 20 % relaxation during push maneuvers, indicating coexisting dyssynergic defecation. 1
- Failure to expel a 50 mL water‑filled balloon within 1–3 minutes, supporting pelvic‑floor dyssynergia. 1
A diagnosis of rectal sensory impairment requires at least two abnormal sensory thresholds to account for the subjective nature of sensory testing. 1
When to Add Imaging
Fluoroscopic or MR defecography is recommended only when manometry and balloon‑expulsion results are discordant or when structural pelvic‑floor lesions (e.g., rectoceles, intussusception) are suspected. 1
MR defecography is not indicated as an initial imaging study for acute pelvic‑floor hypertonicity; it is reserved for chronic defecatory disorders unresponsive to conservative therapy. 1
In this patient, three years post‑surgery with chronic symptoms, defecography may be considered if manometry is equivocal or if the patient fails biofeedback therapy. 1
Laboratory and Endoscopic Evaluation
Only a complete blood count is routinely required; metabolic panels (glucose, calcium, thyroid studies) are not ordered unless systemic symptoms are present. 1
Colonoscopy is not indicated unless alarm features (rectal bleeding, anemia, weight loss) are present or age‑appropriate cancer screening has not been completed. 1
Management Strategy
Phase 1: Immediate Symptomatic Relief (First 1–2 Weeks)
Discontinue all constipating medications (opioids, anticholinergics, calcium‑channel blockers, iron supplements). 1
Initiate polyethylene glycol ≈ 17 g daily (osmotic laxative) to soften stools and reduce straining. 1
Add bisacodyl ≈ 10 mg orally once daily (stimulant laxative) to promote regular bowel movements. 1
Encourage fluid intake of at least 1.5 L/day and advise toileting habits: defecate ≈ 30 minutes after meals (gastrocolic reflex), use a footstool to achieve a squatting position, and limit straining to ≤ 5 minutes. 1
Avoid high‑dose fiber or bulk laxatives until adequate hydration is ensured, as they can worsen outlet obstruction. 1
Phase 2: Definitive Therapy—Biofeedback for Sensory Retraining and Pelvic‑Floor Coordination
Biofeedback therapy is the definitive first‑line treatment, carrying a Grade A recommendation with a 70–80 % success rate for dyssynergic defecation. 1
For this patient, a comprehensive biofeedback protocol is required that addresses both pelvic‑floor muscle coordination and sensory retraining. 1
Sensory retraining biofeedback leads to measurable improvement in rectal sensory function and alleviates symptoms of both constipation and fecal incontinence; approximately 76 % of patients with refractory anorectal complaints achieve adequate symptom relief. 1
Typical protocol: 4–6 sessions over 8–12 weeks with a trained pelvic‑floor therapist, using visual or auditory feedback to train patients to relax pelvic‑floor muscles during straining and to recognize lower rectal‑distension thresholds. 1
Predictors of success: lower baseline rectal sensory thresholds and absence of depression. 1
Predictors of failure: elevated first‑sensation threshold and presence of depression. 1
Phase 3: Concurrent Psychiatric Management of OCD
Screen for depression before initiating biofeedback, because depression is linked to higher first‑sensation rectal sensory thresholds and independently predicts poor response to biofeedback therapy. 1
Initiate Cognitive Behavioral Therapy with Exposure and Response Prevention (ERP) as first‑line treatment for the OCD component. 4
The ERP protocol should target the compulsive body‑scanning and tensing behaviors: the patient must learn to tolerate the absence of the "grounding" sensation without performing the compulsive search. 4
Consider sertraline 50 mg daily as first‑line SSRI pharmacotherapy for moderate‑to‑severe OCD symptoms; higher doses (up to 200 mg daily) are often needed for OCD compared to other psychiatric disorders. 5
Reassure the patient that the obsessive urge to search for the sensation is a manifestation of OCD, not a sign of ongoing surgical damage, and that ERP will reduce the compulsive drive over time. 4
Phase 4: Escalation When Biofeedback Fails
If biofeedback is unavailable or unsuccessful after 8–12 weeks, order a colonic transit study, because ≈ 30 % of patients have combined dyssynergic defecation and slow‑transit constipation. 1
If slow transit is confirmed, add prucalopride ≈ 2 mg daily (prokinetic with strong evidence for slow‑transit constipation). 1
If normal transit is confirmed, reassess rectal sensory impairment and consider a second course of sensory‑retraining biofeedback. 1
Refer to colorectal surgery only when structural abnormalities (e.g., large rectocele, rectal prolapse) are identified on defecography. 1
Common Pitfalls to Avoid
Do not dismiss the patient's symptoms as purely psychiatric—the sensory impairment is a real physiologic consequence of hemorrhoidectomy, and the OCD is a secondary maladaptive response to that loss. 2, 1
Do not assume the patient has irritable bowel syndrome without first excluding a defecatory disorder; the two conditions overlap in ≈ 30 % of cases but require different therapies. 1
Do not order colonic transit studies before anorectal testing; up to one‑third of patients have secondary slowing due to untreated dyssynergia. 1
Do not prescribe high‑dose fiber or bulk laxatives, as they increase stool volume that cannot be evacuated. 1
Do not proceed to surgical interventions without confirming normal anorectal function; unrecognized dyssynergia leads to disastrous surgical outcomes. 1
Do not treat the OCD component in isolation—the compulsive body‑scanning will persist as long as the underlying sensory deficit remains unaddressed. 1, 4
Referral Pathway
Refer to gastroenterology or a pelvic‑floor specialist for anorectal manometry, balloon‑expulsion testing, and biofeedback therapy. 1
Refer to psychiatry or a psychologist trained in ERP for concurrent management of the OCD component. 4
Refer to colorectal surgery only if defecography reveals structural pelvic‑floor abnormalities requiring repair. 1