What are the criteria for determining if a linear cut requires suturing, considering factors such as depth, length, location, and patient's overall health, including history of diabetes, immunosuppression, or previous surgeries?

Criteria for Linear Cuts Requiring Suturing

Suture any linear cut that extends through the dermis into subcutaneous fat, involves muscle or fascia, has gaping edges that cannot be approximated with tape alone, is located in high-tension areas, or is on the face where optimal cosmetic outcome is essential. 1

Depth Assessment (Primary Determinant)

Full-thickness dermal wounds require suturing when the cut penetrates beyond the dermis into subcutaneous tissue, as these wounds cannot heal adequately by secondary intention without significant scarring. 2

• Superficial cuts (epidermis only or superficial dermis): Do not require sutures; can be managed with adhesive strips or tissue adhesive 1
• Deep dermal cuts (through dermis into fat): Require suturing to achieve proper wound edge approximation 2
• Cuts involving muscle, fascia, or deeper structures: Mandatory suturing with layered closure to restore anatomical integrity 2

Length Considerations

• Facial wounds >0.5 cm: Generally benefit from suturing for optimal cosmetic outcome, even if superficial 1
• Trunk and extremity wounds >1-2 cm: Require suturing if full-thickness, as tissue adhesives have higher dehiscence rates (RR 3.35; 95% CI 1.53-7.33) 1
• Scalp lacerations >1 cm: Should be sutured due to high vascularity and tension 3

Location-Specific Criteria

High-tension anatomic sites mandate suturing regardless of length:

• Joints and flexor surfaces: Require suturing due to constant movement and tension 2
• Scalp: Requires suturing for hemostasis control and to prevent gaping 3
• Face: Suture all full-thickness wounds for cosmetic optimization, using subcuticular technique 1, 4
• Hands and feet: Suture to maintain function and prevent wound breakdown 2

Wound Edge Assessment

Gaping wounds require suturing when edges cannot be approximated to within 2-3 mm with gentle pressure, as this indicates tension that will prevent adequate healing. 2

• Wounds with edges that spontaneously approximate may be managed with adhesive strips 1
• Wounds under tension (edges pull apart >5 mm) require deep dermal sutures before superficial closure 1

Patient-Specific Risk Factors Requiring Lower Threshold for Suturing

Immunocompromised patients, diabetics, and those on chronic steroids require suturing for smaller wounds than would otherwise be necessary, as these conditions impair wound healing and increase infection risk. 2

• Diabetes: Suture wounds >0.5 cm due to impaired healing capacity 2
• Immunosuppression: Lower threshold for suturing to prevent wound complications 2
• Chronic steroid use: Increases risk of dehiscence; suture liberally 2
• Previous keloid formation: Consider tissue adhesive alternatives when appropriate 1

Contraindications to Primary Suturing

Do not primarily suture contaminated wounds, bites (except facial), or wounds >12-24 hours old without thorough debridement and consideration for delayed primary closure. 2

• Heavily contaminated wounds require irrigation and debridement before closure decision 2
• Animal/human bites (except face): Leave open for delayed closure 2
• Wounds presenting >12 hours (>24 hours on face): Consider delayed primary closure 2

Time-Sensitive Closure Windows

• Face: Can suture up to 24 hours post-injury due to excellent vascularity 1
• Trunk and extremities: Optimal closure within 6-12 hours 2
• Contaminated wounds: May require delayed primary closure at 3-5 days 2

Common Pitfalls to Avoid

• Never use tissue adhesive alone on high-tension wounds, as dehiscence rates are significantly higher (RR 3.35) 1
• Avoid suturing through infected tissue without adequate debridement and antibiotic coverage 2
• Do not close wounds under excessive tension without undermining or deep dermal sutures, as this causes tissue strangulation 3, 1
• Never assume superficial appearance means no deep structure involvement; always assess full depth 2