What is the estimated percentage of total body surface area (TBSA) affected in an adult patient with burns to the 2nd, 3rd, 4th, and 5th fingers?

Burn Surface Area Estimation for Finger Burns

Burns to the 2nd, 3rd, 4th, and 5th fingers represent approximately 2-3% of total body surface area (TBSA) in an adult, calculated using the hand surface area method where the entire hand (palm plus all fingers) equals approximately 2.5% TBSA. 1

Calculation Method

Use the Lund-Browder chart as your primary assessment tool for accurate TBSA calculation, as it is the most accurate standardized method for both adults and children. 2, 1

For practical estimation of finger burns specifically:

• The entire hand (palm plus all five fingers) represents approximately 2.5% TBSA in adults on the Lund-Browder chart 1
• Since you have burns to four fingers (excluding the thumb), this represents roughly 2-3% TBSA, as the four fingers comprise the majority of the hand's surface area excluding the palm and thumb 3
• Each individual finger surface (all four sides plus tip) requires approximately 2 thumbprints on volar, dorsal, radial and ulnar surfaces, totaling about 8-10 thumbprints per finger 3

Alternative Quick Estimation

• The palm (excluding fingers) alone represents 0.5% TBSA 1, 4
• The palm including all digits represents 0.8-1.0% TBSA 1, 4
• One thumbprint area equals approximately 1/30th of 1% TBSA 3

Critical Management Implications

This burn requires immediate specialist referral regardless of the percentage, as any partial-thickness or full-thickness hand burns require immediate specialist consultation due to high risk of functional sequelae. 5

• Deep burns to the hands are considered severe burns requiring burn center evaluation, even when TBSA is small, because hands are function-sensitive areas 2
• Adults with burns to hands/fingers meet criteria for burn specialist consultation to determine if burn center admission is needed 2, 5

Common Pitfalls to Avoid

• Do not use the Rule of Nines for small burns like isolated finger injuries, as it lacks the precision needed and significantly overestimates TBSA 1
• Do not delay specialist referral while attempting outpatient management for function-sensitive area burns 5
• Perform repeated assessments during initial care, as TBSA estimates are often inaccurate on first evaluation and are overestimated in 70-94% of cases 2, 1