Overview
Definition:
Retromuscular mesh repair, also known as the preperitoneal approach, involves placing a synthetic mesh in the plane between the posterior rectus sheath and the peritoneum, or between the transversalis fascia and the peritoneum, for hernia repair
This approach provides strong prosthetic reinforcement to the abdominal wall defect, reducing recurrence rates
The open approach allows for direct visualization and palpation of the anatomy, often preferred for certain hernia types or in specific patient populations.
Epidemiology:
Hernias, particularly inguinal and ventral (incisional, umbilical, epigastric), are common conditions affecting millions worldwide
Inguinal hernias occur in 5-30% of men and 0.5-4% of women
Ventral hernias account for approximately 10-15% of all abdominal hernias
Recurrence rates after hernia repair can range from 5-20% depending on the technique and complexity, making mesh reinforcement crucial.
Clinical Significance:
Retromuscular mesh repair is a cornerstone in modern hernia surgery, significantly lowering recurrence rates compared to purely tissue-based repairs
Understanding this technique is vital for surgical residents preparing for DNB and NEET SS examinations, as it represents a standard of care for numerous hernia types
Proper execution of this procedure is key to achieving durable repairs and minimizing patient morbidity.
Indications
Indications:
Primary or recurrent inguinal hernias (direct, indirect, femoral)
Large or complex ventral hernias (incisional, umbilical, epigastric)
Patients requiring prosthetic reinforcement due to weakened abdominal wall
Cases where laparoscopic approach is contraindicated or not feasible
Recurrent hernias after previous open repairs not involving the retromuscular space.
Contraindications:
Active infection at the surgical site
Uncorrected coagulopathy
Patient refusal or inability to tolerate surgery
Severe medical comorbidities precluding anesthesia
Highly contaminated wounds
Large intra-abdominal contents (requiring staged repair or other techniques).
Preoperative Evaluation:
Thorough history and physical examination to define hernia type and size
Assessment of patient's comorbidities and anesthesia risk
Review of previous surgeries
Counseling on risks, benefits, and alternatives, including recurrence rates
Imaging (ultrasound, CT scan) may be used for complex or recurrent ventral hernias to delineate anatomy and defect size.
Preoperative Preparation
Patient Optimization:
Optimize nutrition, especially for malnourished patients
Ensure adequate glycemic control in diabetic patients
Address obesity and smoking cessation where appropriate
Prophylactic antibiotics are typically administered intravenously within 60 minutes of incision, tailored to the surgical flora (e.g., cefazolin).
Anesthesia Considerations:
Can be performed under general, spinal, or even local anesthesia with sedation depending on the patient, hernia type, and surgeon preference
General anesthesia is most common for larger or more complex repairs.
Surgical Setup:
Standard sterile surgical preparation and draping of the abdomen and groin
Careful positioning of the patient to allow optimal surgical access
Use of appropriate surgical instruments, including retractors, mesh tools, and fixation devices.
Procedure Steps
Incision And Dissection:
An incision is made over the hernia defect
For inguinal hernias, a curvilinear incision in the groin (Lichtenstein approach) or a midline incision for ventral hernias
The dissection proceeds down to the anterior rectus sheath
The anterior rectus sheath is incised longitudinally, and the rectus muscle is identified
Retraction of the rectus muscle laterally exposes the posterior rectus sheath or transversalis fascia.
Identification Of Defect:
The peritoneal sac and hernia contents are identified and reduced back into the abdominal cavity
The defect in the transversalis fascia or posterior rectus sheath is clearly delineated
Careful assessment for any associated defects or weaknesses in the abdominal wall.
Mesh Placement:
A synthetic mesh of appropriate size and type (e.g., polypropylene, composite) is selected
The mesh is placed in the retromuscular space, ensuring it is adequately larger than the defect (typically 2-3 cm overlap in all directions)
The mesh should lie flat without tension and cover the entire myopectineal orifice for inguinal hernias or the fascial defect for ventral hernias.
Mesh Fixation:
Depending on the approach and mesh used, fixation may be required
This can involve non-absorbable sutures to tack the mesh to the surrounding fascia (e.g., Cooper's ligament, pectineal ligament for inguinal hernias
posterior rectus sheath for ventral hernias)
Alternatively, tacks or glues can be used, though their routine use is debated
Tension-free placement is paramount.
Fascial Closure:
The anterior rectus sheath is closed over the mesh with non-absorbable sutures to provide an additional layer of reinforcement and reduce seroma formation
For ventral hernias, the fascial defect itself may be closed if feasible, followed by mesh placement in the retromuscular space and anterior fascial closure.
Postoperative Care
Pain Management:
Adequate analgesia is crucial
This may include multimodal approaches: patient-controlled analgesia (PCA) with opioids, oral analgesics (NSAIDs, acetaminophen), and regional blocks (e.g., transversus abdominis plane (TAP) block).
Mobilization And Activity:
Early mobilization is encouraged to prevent deep vein thrombosis (DVT) and pulmonary complications
Patients are advised to avoid heavy lifting and strenuous activities for 4-6 weeks, with gradual return to normal activities.
Wound Care And Monitoring:
Wound is dressed with sterile dressings
Patients are instructed on signs of infection, seroma, or hematoma
Regular monitoring for fever, increasing pain, wound discharge, or redness
Drain placement is uncommon but may be used in complex cases.
Discharge Planning:
Discharge typically occurs within 24-48 hours for uncomplicated cases
Patients receive instructions on wound care, pain management, activity restrictions, and follow-up appointments
They are advised to contact their physician if any concerning symptoms arise.
Complications
Early Complications:
Wound infection
Seroma formation
Hematoma
Pain
Urinary retention
Bowel obstruction (rare)
Nerve injury (e.g., chronic groin pain).
Late Complications:
Mesh infection
Mesh migration or extrusion (rare with proper fixation)
Chronic pain
Recurrence (despite mesh)
Adhesions
Bowel obstruction due to adhesions.
Prevention Strategies:
Meticulous surgical technique, including proper handling of tissues and mesh
Adequate mesh overlap and fixation
Strict aseptic technique
Prophylactic antibiotics
Appropriate pain management to facilitate early mobilization
Patient education on post-operative restrictions.
Prognosis
Factors Affecting Prognosis:
Hernia type and size
Patient's comorbidities (obesity, diabetes)
Surgical technique and mesh used
Surgeon's experience
Patient compliance with post-operative instructions
Presence of wound infection or seroma.
Outcomes:
Retromuscular mesh repair generally offers excellent long-term outcomes with low recurrence rates, typically <5% for primary inguinal hernias and generally lower than tissue-only repairs for ventral hernias
Functional recovery is usually good with appropriate rehabilitation.
Follow Up:
Routine follow-up appointments are recommended at 2-4 weeks post-operatively to assess wound healing and patient recovery
Further follow-up may be scheduled at 6-12 months or as needed
Patients should be educated on long-term self-monitoring for any signs of recurrence or complications.
Key Points
Exam Focus:
Understand the anatomical plane for retromuscular mesh placement
Differentiate between anterior (sublay) and posterior (preperitoneal) retromuscular approaches
Know the indications and contraindications for open mesh repair
Recall common mesh materials and fixation methods
Be aware of potential complications and their management.
Clinical Pearls:
Adequate mesh overlap is critical for durability
Tension-free placement is the hallmark of successful mesh repair
Early and adequate pain control facilitates recovery and reduces complications
Proper patient selection and counseling are essential for managing expectations regarding activity restrictions.
Common Mistakes:
Inadequate mesh size or overlap
Mesh placed under tension
Incomplete reduction of hernia sac
Failure to close the anterior rectus sheath in ventral repairs
Overlooking associated anatomical defects
Inadequate post-operative pain management leading to poor mobility.