What is the most important consideration in a knife laceration to the hand?

Assessment of Knife Lacerations to the Hand

The most critical consideration in a knife laceration to the hand is identifying underlying injuries to tendons, nerves, and neurovascular structures, as these cannot heal without surgical repair and require urgent evaluation under tourniquet with expeditious referral for surgical intervention. 1, 2, 3

Primary Assessment Priorities

Immediate Evaluation for Deep Structure Injury

• Surface examination is inadequate and frequently misleading – penetrating injuries to the hand place vital neurovascular, tendon, and nerve structures at high risk, and wound appearance does not correlate with extent of underlying damage 1

• Subclinical injuries are extremely common – in full-thickness hand lacerations, 49% harbor deep injuries not detected on clinical examination before formal exploration, including 33% with tendon lacerations 3

• Formal exploration under tourniquet is essential for any laceration penetrating full thickness of subcutaneous tissue, as this reveals injuries that would otherwise be missed and prevents complications like delayed tendon rupture 3

Vascular Assessment

• Check for perfusion immediately – vascular damage in the hand can result in life-threatening exsanguinating hemorrhage or permanent disability from nerve damage 1

• Absent pulses or decreased perfusion require emergent intervention – these findings mandate immediate reduction/exploration to prevent limb loss, ischemic contracture, and functional deficit 1

Wound Management Protocol

Initial Care Standards

• Perform hand hygiene with antimicrobial soap and water or alcohol-based hand rub before patient contact 4

• Irrigate thoroughly with sterile normal saline and remove superficial debris; avoid iodine or antibiotic-containing irrigation solutions 4

• Explore under tourniquet (mean inflation time 4.9 minutes is safe and effective) to identify all tendon, nerve, and vascular injuries 3

Antibiotic Prophylaxis Decision-Making

Prophylactic antibiotics are indicated for high-risk wounds only, not routine simple lacerations 4, 5:

High-risk criteria requiring prophylaxis:

• Immunocompromised, asplenic, or advanced liver disease patients 4
• Moderate to severe injuries with resultant edema 4
• Injuries potentially penetrating periosteum or joint capsule 4
• Significant wound contamination 4

For high-risk wounds:

• Amoxicillin-clavulanate 875/125 mg twice daily is first-line prophylaxis 4
• Duration: 3-5 days for prophylaxis 4
• Extended treatment if established infection develops: 3-4 weeks for septic arthritis, 4-6 weeks for osteomyelitis 4

Simple hand lacerations without high-risk features:

• Infection rate is only 4.8% without antibiotics 5
• Prophylactic antibiotics do not reduce infection rates in simple lacerations (7% with antibiotics vs 4% without, P=0.66) 5

Surgical Referral Indications

Urgent surgical referral is mandatory for:

• Any tendon laceration (tendons cannot heal without surgical approximation) 2
• Any nerve laceration (requires surgical repair for healing) 2
• Neurovascular injuries 1, 2
• Injuries penetrating joint capsules or periosteum 4

Common pitfall: Approximately 21 tendons per 100 full-thickness lacerations require repair, with 19% of patients needing immobilization in volar slab for ≥3 weeks – missing these injuries leads to permanent functional impairment 3

Tetanus Prophylaxis

• Administer tetanus toxoid if not vaccinated within 10 years 1
• Tdap is preferred over Td if not previously given 1
• For dirty wounds, give booster if >5 years since last dose; for clean wounds, if >10 years 1