Is it normal for a 6-month post-fistulotomy patient to experience stool coming out the left side of the fistulotomy site and the hole being pulled slightly to the left during defecation?

Post-Fistulotomy Healing at 6 Months: Stool Deviation and Asymmetric Wound Contraction

The symptoms you describe—stool coming out the left side of the fistulotomy site with leftward pulling of the opening—are concerning for incomplete healing with possible tract persistence or keyhole deformity, and require immediate clinical and imaging evaluation to rule out recurrent fistula or abscess formation. 1, 2

Understanding What May Be Happening

At 6 months post-fistulotomy, complete wound healing should have occurred in 97% of cases within 1-6 months 3. Your symptoms suggest one of three scenarios:

Most Likely: Keyhole Deformity with Sphincter Dysfunction

• Keyhole deformity occurs when the fistulotomy wound heals with asymmetric scarring and sphincter retraction, creating a characteristic notch or "keyhole" appearance at the anal opening 4
• This deformity causes stool to preferentially exit through the defect (in your case, the left side) rather than through the normal anal canal 4
• Keyhole deformity develops in approximately 25% of patients after simple fistulotomy, particularly with posteriorly located fistulas 4
• The leftward "pulling" sensation represents sphincter muscle retraction and scar contracture at the healing site 1, 4

Alternative Concern: Incomplete Fistula Healing or Recurrence

• Fistula recurrence occurs in 3-3.5% of cases after fistulotomy, typically manifesting within the first year 3, 5
• Persistent drainage through the original fistulotomy site suggests the tract may not have fully epithelialized or a new tract has formed 6, 1
• Active proctitis or rectal inflammation (if you have Crohn's disease) dramatically impairs wound healing and increases recurrence risk 6

Less Common: Occult Abscess Formation

• Hidden abscess cavities can develop even after apparent wound healing, presenting as persistent drainage 5
• This occurs in approximately 1-2% of post-fistulotomy patients 5

Critical Diagnostic Evaluation Required Immediately

You need the following tests to determine the exact cause:

Mandatory Imaging

• Endoanal ultrasound must be performed to assess for active inflammation, fluid collections, structural sphincter defects, or persistent fistula tracts 1, 2
• MRI of the pelvis is recommended if ultrasound is inconclusive, as it can detect hidden fistulous tracts ending in abscess cavities that are not clinically apparent 5

Functional Assessment

• Anorectal manometry is essential to quantify sphincter pressures and determine the degree of sphincter dysfunction from the fistulotomy 1, 2
• Normal values for males are mean resting pressure >50 mmHg and maximum squeeze pressure >100 mmHg 2

Clinical Examination

• Evaluation for active proctitis or rectal inflammation is necessary, as this would explain persistent symptoms and contraindicate any further surgical intervention 1, 2, 6
• If you have Crohn's disease, your Crohn's Disease Activity Index should be assessed (must be <150 for any surgical consideration) 7, 6

What This Means for Your Management

If Keyhole Deformity is Confirmed (Most Likely Scenario)

Symptomatic management should be initiated immediately:

• Apply topical 0.3% nifedipine with 1.5% lidocaine ointment three times daily for at least 6 weeks to reduce sphincter hypertonicity and promote healing 1, 2
• Expect symptom relief after 14 days of consistent use 1, 2
• Add oral analgesics (paracetamol or ibuprofen) for severe discomfort episodes 1, 2

Adjunctive measures:

• Maintain a high-fiber diet (25-30g daily) with adequate water intake to prevent constipation and reduce anal trauma 1
• Perform warm sitz baths to promote sphincter relaxation and healing 1
• Consider topical metronidazole cream if poor hygiene or low-grade infection is suspected 1

Surgical correction options (only after inflammation resolves):

• Fistulotomy with immediate primary sphincter reconstruction can be considered if there is no active proctitis and you are medically optimized 1, 7, 8
• This technique has a 95.8% success rate with healing at mean follow-up of 29 months 8
• However, 11.6% of patients develop de novo post-defecation soiling 8
• Ligation of intersphincteric fistula tract (LIFT) is an alternative for complex cases, with healing rates of 60-90% 1, 6

If Recurrent Fistula is Confirmed

• Non-cutting seton placement is the treatment of choice to maintain drainage and prevent abscess formation 6
• Setons can be removed after a median of 33 weeks when combined with optimal medical therapy, with success rates up to 98% 6
• If you have Crohn's disease, combination therapy with anti-TNF agents (infliximab or adalimumab) plus seton drainage provides superior outcomes compared to either treatment alone 6

If Abscess is Detected

• Immediate surgical drainage is required before any other intervention 6
• Seton placement should follow drainage to prevent recurrence 6

Critical Pitfalls to Avoid

Do NOT undergo the following procedures, as they will worsen your condition:

• Cutting setons result in 57% incontinence rates from progressive sphincter transection and are strongly contraindicated 6, 1, 7
• Repeat sphincterotomy would further compromise your already damaged sphincter and make functional restoration impossible 1, 7
• Aggressive dilation causes permanent sphincter injury in 10% of patients 1, 7
• Any surgical intervention while active proctitis or rectal inflammation is present will fail and cause additional complications 6, 1

Setting Realistic Expectations

Complete restoration of pre-surgical anatomy and function may not be achievable given the extent of sphincter division during your fistulotomy 1, 2. The goal is to:

• Maximize healing of the current surgical site 1
• Objectively assess residual sphincter function 1
• Prevent further deterioration through conservative management 1, 2

Sphincter hypertonicity and sensory abnormalities typically improve over 6-12 months with conservative management including topical calcium channel blockers and pelvic floor exercises 2. However, some degree of altered sensation or minor soiling may persist long-term 8, 4.

Immediate Next Steps

1. Schedule urgent consultation with a colorectal surgeon experienced in perianal disease 6
2. Obtain endoanal ultrasound and consider MRI if indicated 1, 2, 5
3. Begin topical nifedipine/lidocaine therapy while awaiting evaluation 1, 2
4. Avoid constipation and maintain excellent perianal hygiene 1
5. Do not consent to any cutting procedures until complete diagnostic evaluation is performed 6