Overview
Definition:
A perineal hernia after an abdominoperineal resection (APR) is the protrusion of abdominal contents through a defect in the pelvic floor, typically in the perineal region, following the surgical removal of the rectum and anus
This occurs due to the loss of structural integrity of the pelvic diaphragm and surrounding tissues
It represents a complex reconstructive challenge, often associated with significant morbidity.
Epidemiology:
The incidence of perineal hernia following APR varies widely in literature, ranging from 5% to over 50% in some series, depending on the definition, follow-up duration, surgical technique, and patient factors
Factors increasing risk include large defects, obesity, advanced age, previous pelvic surgery, and adjuvant radiation therapy.
Clinical Significance:
Perineal hernias post-APR can lead to chronic pain, discomfort, difficulty with ambulation, sexual dysfunction, and, in severe cases, bowel obstruction or strangulation
Accurate diagnosis and timely surgical intervention are crucial to alleviate symptoms, prevent complications, and improve the patient's quality of life
Understanding this complication is vital for surgical residents preparing for DNB and NEET SS examinations.
Clinical Presentation
Symptoms:
A palpable bulge or swelling in the perineal region, often exacerbated by coughing or straining
Discomfort or pain in the perineum
Sensation of fullness or pressure
Bowel habit changes, such as increased frequency or urgency
Difficulty with defecation
Recurrent perineal wound infections or dehiscence
Incarceration or strangulation symptoms: severe pain, nausea, vomiting, and inability to pass flatus or stool.
Signs:
A visible or palpable perineal mass, which may be reducible
Tenderness on palpation
Signs of inflammation if incarcerated or strangulated
Potential for skin changes over the hernia sac
Examination may reveal a defect in the pelvic floor at the perineal site.
Diagnostic Criteria:
Diagnosis is primarily clinical, based on the characteristic perineal bulge and symptoms
Imaging may be used to confirm the diagnosis and assess the extent of the hernia, particularly in recurrent or complex cases
No formal standardized diagnostic criteria exist, but a high index of suspicion in patients post-APR with perineal symptoms is key.
Diagnostic Approach
History Taking:
Detailed history of the initial APR procedure, including surgical technique, any complications, and adjuvant therapies
Onset and progression of perineal symptoms
Aggravating and relieving factors for the bulge and pain
Bowel function assessment
Any prior attempts at hernia repair
Past surgical history, comorbidities, and medications.
Physical Examination:
Thorough perineal examination, including inspection for scars, masses, and skin changes
Palpation to assess the size, consistency, reducibility, and tenderness of any perineal bulge
Assessment of pelvic floor muscle strength
Examination of the anal canal and surrounding tissues
A digital rectal examination may reveal associated abnormalities
Patients may be asked to strain or cough to elicit the hernia.
Investigations:
Imaging modalities are often employed to confirm the diagnosis and delineate the hernia anatomy
CT scan of the pelvis is useful for visualizing abdominal contents within the perineal sac and assessing the size of the defect
MRI can provide better soft tissue detail and assess the pelvic floor muscles and surrounding structures
Ultrasound may be used in specific cases but is less comprehensive
Laboratory investigations are usually not primary but may be indicated for complications such as infection.
Differential Diagnosis:
Perineal abscess
Rectovaginal or rectourethral fistula
Scar dehiscence or seroma
Hematoma
Soft tissue tumor
Prolapse of other pelvic organs (e.g., vaginal vault prolapse)
Pelvic lymphocele
It is crucial to distinguish a true perineal hernia from other perineal pathologies.
Management
Initial Management:
For asymptomatic or minimally symptomatic hernias, conservative management with supportive measures may be considered
For symptomatic, incarcerated, or strangulated hernias, urgent surgical intervention is indicated
Patients with signs of strangulation require immediate resuscitation and surgical exploration.
Surgical Management:
The goal of surgical management is to reduce the herniated contents, repair the pelvic floor defect, and prevent recurrence
Multiple techniques exist: Primary suture repair of the pelvic floor defect
Use of autologous tissue grafts (e.g., gracilis muscle flap, gluteal muscle flap) to reinforce the defect
Prosthetic mesh repair, although this carries a higher risk of infection in the perineal area
Combined abdominal and perineal approaches (e.g., sacrocolpopexy, posterior component separation)
The choice of technique depends on the size of the defect, patient factors, surgeon's experience, and whether it is a primary or recurrent hernia.
Supportive Care:
Preoperative optimization of nutritional status and management of comorbidities
Postoperative care includes pain management, early ambulation, wound care, and bowel regimen to prevent constipation
Careful monitoring for signs of infection, seroma formation, or recurrence
In some cases, temporary diversion of the fecal stream may be necessary, although it is less commonly performed in elective repairs.
Complications
Early Complications:
Wound infection
Seroma formation
Hematoma
Skin necrosis
Fecal fistula or leakage
Recurrence of hernia
Nerve injury.
Late Complications:
Chronic perineal pain
Sexual dysfunction
Recurrence of hernia
Chronic wound breakdown
Difficulty with defecation.
Prevention Strategies:
Meticulous surgical technique during APR to preserve pelvic floor integrity
Careful closure of the perineal defect
Judicious use of drains
Optimizing patient factors pre- and post-operatively, such as weight management and smoking cessation
Consideration of reconstructive techniques that provide robust support to the pelvic floor
Early recognition and management of wound complications.
Prognosis
Factors Affecting Prognosis:
Recurrence rates vary significantly with the repair technique and surgeon experience, ranging from 10% to over 40% for simple repairs
Factors influencing outcome include hernia size, presence of comorbidities, previous repairs, and the method of pelvic floor reconstruction
Early diagnosis and intervention generally lead to better outcomes.
Outcomes:
Successful repair can alleviate symptoms, improve quality of life, and prevent serious complications
However, recurrence remains a significant concern, especially with less robust reconstructive methods
Long-term functional outcomes, including bowel function and sexual health, can be affected by both the initial APR and the subsequent hernia repair.
Follow Up:
Regular follow-up is essential to monitor for recurrence, assess wound healing, and manage any long-term sequelae
Follow-up schedule typically involves clinical examinations at 1, 3, 6, and 12 months post-operatively, and then annually
Imaging may be considered if recurrence is suspected clinically.
Key Points
Exam Focus:
Understand the high incidence of perineal hernia post-APR and the varied definitions
Know the indications for surgical repair (symptomatic, incarcerated, strangulated)
Be familiar with various surgical techniques: primary repair, autologous flaps, mesh (with caution), and combined approaches
Recognize the significant risk of recurrence and factors influencing it.
Clinical Pearls:
A high index of suspicion is paramount in patients with perineal symptoms post-APR
Always perform a thorough perineal examination, including asking the patient to strain
Consider imaging (CT/MRI) for large or complex hernias or suspected recurrence
Involve multidisciplinary teams for complex reconstructive cases
Be aware of the contraindications and limitations of mesh in the perineal region post-APR.
Common Mistakes:
Underestimating the incidence or significance of perineal hernias post-APR
Inadequate closure of the pelvic floor defect during the initial APR
Inappropriate selection of repair technique, especially relying solely on simple suture closure for large defects
Delaying surgical intervention for symptomatic hernias
Neglecting long-term follow-up, leading to missed recurrences.