Which suture materials and sizes are optimal for different wound types (e.g., superficial clean lacerations, deeper moderate‑tension wounds, contaminated or high‑tension wounds, and fascia or tendon repairs)?

Optimal Suture Selection by Wound Type

For most wound closures, use monofilament sutures: slowly absorbable monofilament (e.g., PDS) for deep layers and fascia, and non-absorbable monofilament (polypropylene or nylon) for skin, with antimicrobial-coated sutures strongly recommended for contaminated fields.

Superficial Clean Lacerations

For simple skin lacerations with minimal tension:

• Skin closure: 5-0 to 6-0 non-absorbable monofilament (polypropylene or nylon) 1
• Alternative: Absorbable monofilament like polyglycolic acid (Dexon) eliminates need for suture removal with comparable infection rates to silk, polyethylene, or nylon 2
• Technique consideration: If wound edges approximate naturally under minimal tension, dermal sutures can be avoided entirely 1

Deeper Moderate-Tension Wounds

For layered closures requiring fascial support:

• Deep/superficial fascia: 0 to 2-0 polydioxanone (PDS II) 1
• Dermal layer (if needed): 4-0 to 5-0 PDS II 1
• Skin: 6-0 to 7-0 polypropylene or nylon 1

Key principle: Place tension on fascial layers, not dermis, to minimize scarring and optimize wound edge elevation 1

Contaminated or High-Tension Wounds

Critical recommendation: Use antimicrobial-coated (triclosan-impregnated) monofilament sutures for fascial closure in clean-contaminated and contaminated fields 3. This represents a strong recommendation based on high-quality RCTs showing significantly lower surgical site infection rates 3.

Important caveat: The tensile strength reduction over time does not differ between contaminated versus clean conditions, even for absorbable sutures 4. However, silk shows significantly more severe inflammation under contaminated conditions and should be avoided 4.

For emergency laparotomy closures specifically:

• Monofilament slowly absorbable sutures are strongly recommended over multifilament due to significantly lower incisional hernia rates 3
• Use "small bite" technique when possible 3

Fascia or Tendon Repairs

Tendon repairs require special consideration:

• Strongest materials: Non-absorbable synthetic fibers like Supramid or polypropylene 5
• Avoid: Stainless steel (difficult to work with, bulky knots) and absorbable sutures (become too weak too quickly) 5
• Technique: Bunnell, Kessler, or Mason-Allen techniques provide strongest repairs, though Bunnell is more strangulating to microcirculation 5
• Clinical pearl: Less traumatic techniques facilitate tendon sheath closure and synovial fluid continuity, critical for nutrition and healing 5

Fascial closures in emergency settings:

• Monofilament slowly absorbable sutures (1A evidence) 3
• Consider antimicrobial coating for clean-contaminated/contaminated fields 3

Critical Pitfalls to Avoid

1. Never use multifilament sutures for fascial closure in emergency settings—significantly higher incisional hernia rates 3

2. Avoid silk in contaminated wounds—shows more severe inflammatory response 4

3. Don't over-suture dermis—place tension on fascial layers instead to prevent large scars 1

4. Absorbable sutures are inappropriate for tendon repairs—they lose strength before adequate healing occurs 5

Wound Classification Context

The CDC classification system guides suture selection 6:

• Class I (clean): Standard monofilament approach
• Class II (clean-contaminated): Add antimicrobial coating
• Class III (contaminated): Antimicrobial-coated monofilament mandatory
• Class IV (dirty-infected): Antimicrobial-coated monofilament, consider delayed closure

Evidence strength note: The antimicrobial suture recommendation carries moderate certainty of evidence (1B) but strong recommendation strength due to significant SSI reduction in emergency settings 3. The monofilament recommendation for fascial closure carries high certainty evidence (1A) with strong recommendation 3.