From the Guidelines
The muscle repaired during a second-degree perineal laceration is the perineal muscle, specifically the bulbo-cavernosus and transverse perineal muscles, which are reapproximated in a running, continuous, nonlocking fashion 1.
Second-Degree Perineal Laceration Repair
A second-degree perineal laceration repair involves a three-layer closure technique.
- First, the vaginal mucosa is repaired using continuous 2-0 or 3-0 absorbable sutures (like Vicryl) starting above the apex of the laceration and continuing to the hymenal ring.
- Next, the perineal muscles are reapproximated using interrupted or continuous 2-0 absorbable sutures to restore the perineal body's strength.
- Finally, the perineal skin is closed with subcuticular 3-0 absorbable sutures for optimal cosmetic results.
Post-Repair Management
Post-repair management includes:
- Regular perineal hygiene with warm water after urination or bowel movements
- Sitz baths 2-3 times daily for comfort and healing
- Ice packs for the first 24-48 hours to reduce swelling
- Pain management with oral analgesics such as ibuprofen 600mg every 6 hours or acetaminophen 650mg every 4-6 hours
- Stool softeners like docusate sodium 100mg twice daily to prevent constipation Patients should be advised to avoid straining during bowel movements and to maintain adequate hydration and fiber intake.
Healing and Recovery
The repair typically heals within 2-3 weeks, with complete tissue recovery by 6 weeks postpartum 1. This approach effectively restores anatomical integrity while minimizing pain and promoting optimal healing of the perineum. It is also important to consider using rapidly-absorbing suture, despite the increased cost, because of the lower need for postpartum suture removal 1. Additionally, monofilament sutures may be preferred due to less bacterial seeding and lower risk of infection 1. However, the use of skin adhesive or no suture for closure of second-degree perineal lacerations may also be considered, as it has been associated with reduction of pain, analgesia use, and dyspareunia, and improved breastfeeding rates at 3 months postpartum 1.
From the Research
Second-Degree Perineal Laceration Repair
The typical repair and management for a second-degree perineal laceration involve the repair of the perineal muscles, specifically:
- The bulbospongiosus muscle (BSM) 2
- The superficial transverse perineal muscle (STPM) may also be involved, but not always 2
Muscle Anatomy and Injury
Studies have shown that the perineal body is not the site of insertion of perineal muscles, but rather the site along which muscle fibers of these muscles pass uninterrupted from one side to the other 3. The bulbospongiosus and superficial portion of the external anal sphincter (EAS) are continuous anatomically with a common innervation in most specimens 4.
Clinical Implications
The injury to the superficial perineal muscles, particularly the BSM, is associated with increased risk of perineal pain and dyspareunia 2. The extent of the injury, with > 50% BSM ± STPM torn, is significantly associated with higher pain and dyspareunia at 10 days and 6 months postpartum, respectively 2.
Anatomical Considerations for Repair
The skeletal muscle complex between the vagina and anal canal, formed by the confluence of the external anal sphincter, anterior bundle of the levator ani, and superficial transverse perineal muscle, is important for perineum repair 5. Understanding the three-dimensional arrangement of these muscles is crucial for obstetricians and gynecologists repairing obstetric lacerations and treating pelvic floor disorders 5.