Body surface

The body surface (short: KOF or BSA (= body surface area)) is the outer surface of the body covered with skin.

Knowing the body surface of a person is important for the dosage of certain drugs (such as cytostatics and other active ingredients used in oncology ), as well as for estimating skin lesions ( burns ).

Empirical formulas for determining the body surface

With the help of empirical data, some formulas for estimating the body surface area based on body weight and height could be obtained. In practice, very often nomograms used.

• Mosteller formula ^*) : ${\displaystyle S=0{,}01666667\cdot L^{0{,}5}\cdot M^{0{,}5}}$
• Gehan-George formula
  • for children <5 years: ${\displaystyle S=0{,}02667\cdot L^{0{,}42246}\cdot M^{0{,}51456}}$
  • for children and adolescents aged 5–19 years: ${\displaystyle S=0{,}03050\cdot L^{0{,}35129}\cdot M^{0{,}54375}}$
  • for adults age> 19 years ^*) : ${\displaystyle S=0{,}01545\cdot L^{0{,}54468}\cdot M^{0{,}46336}}$
• Haycock formula ^*) : ${\displaystyle S=0{,}024265\cdot L^{0{,}3964}\cdot M^{0{,}5378}}$
• DuBois formula ^*) : ${\displaystyle S=0{,}007184\cdot L^{0{,}725}\cdot M^{0{,}425}}$
• Formula according to Boyd ^*) : ${\displaystyle S=0{,}0332965\cdot L^{0{,}3}\cdot M^{0{,}6157-0{,}00816474\;\ln(M)}}$
• Schlich formula
  • for women ^*) : ${\displaystyle S=0{,}000975482\cdot \mathrm {L} ^{1{,}08}\cdot M^{0{,}46}}$
  • for men ^*) : ${\displaystyle S=0{,}000579479\cdot \mathrm {L} ^{1{,}24}\cdot M^{0{,}38}}$
• Fujimoto formula ^*) : ${\displaystyle S=0{,}008883\cdot L^{0{,}663}\cdot M^{0{,}444}}$
• Takahira formula ^*) : ${\displaystyle S=0{,}007241\cdot L^{0{,}725}\cdot M^{0{,}425}}$
• Livingston-Lee formula:
  • for body mass ≥ 10 kg: ${\displaystyle S=0{,}1173\times M^{0{,}6466}}$
  • for body mass <10 kg: ${\displaystyle S=0{,}1037\times M^{0{,}6724}}$
• Shuter and Aslani formula ^*) : ${\displaystyle \mathrm {S} =0{,}00949\times W^{0{,}441}\times H^{0{,}655}}$

The symbols have the following meanings

• ${\displaystyle S}$ - body surface in m²
• ${\displaystyle L}$ - Height in cm
• ${\displaystyle M}$ - body mass in kg

The Mosteller and Haycock formulas are mainly used to determine the body surface area in children.

The original Boyd formula is:

${\displaystyle S=0{,}0003207\cdot L^{0{,}3}(M\cdot 1000)^{0{,}7285-0{,}0188\log _{10}(M\cdot 1000)}}$ .

In the above compilation it has been reworked a little to achieve better comparability between the various formulas.

The Mosteller formula (in the original ) can also be shown as an alternative as above. ${\displaystyle S={\sqrt {\tfrac {L\cdot M}{3600}}}}$

The Schlich formulas take into account, among other things, the different physique of women and men. In the original, they calculate the specific body surface area (i.e. body surface area per kilogram of body mass) from the body mass index and body mass.

^*)For the marked formulas, Pschyrembel Online has made a calculator available that calculates the body surface area after entering body height and weight. See web links .

Averages

• In 1926 the average body surface area of ​​healthy adults was 1.73 m².
• For men, the average is 1.9 m².
• For women: 1.6 m²
• Premature babies: 0.10 m² with a weight of 1000 g
• Premature babies: 0.15 m² with a weight of 2000 g
• Newborns: 0.25 m²
• 2 month old infant: 0.3 m²
• 2-4 year old children: 0.5 m²
• 5 year old children: 0.75 m²
• 9 year old children: 1.07 m²
• 10 year old children: 1.14 m²; other specification: 1.0 m²
• Children aged 12–13: 1.33 m²

Information / formulas for body parts

For adults one can roughly use the rule of nine, cf. Incineration: Determination of the area burned , apply:

Head 9% + arm 9% + leg 18% (9% on the front and 9% on the back) + torso 36% (9% each on the left and right halves, front and back) + genitals 1% = 100%

In general, the palm (including fingers) accounts for around 1% of the body surface.

In children, the ratio of the upper to the lower body surface is shifted in favor of the upper. This means that in newborns 21% of the KOF is on the head and, in contrast, only 1/3 on the trunk and about 1/3 on the legs.

Head 20% + arms 20% + legs 30% + torso 30% = 100%

There are also formulas for the calculation, e.g. B. after Livingston and Lee:

• Head = A × B × 0.308 (where A = circumference around chin and vertex ; B = coronal circumference around forehead and temples, above the eyebrows)
• Arms = F × (G + H + I) × 0.611 (where F = distance between the acromion and the distal end of the radius when the arm is extended; G = circumference of the upper arm near the axilla ; H = largest circumference on the forearm, below the elbow; I = narrowest circumference of the Forearm, on the head of the ulna
• Hands = J × K × 2.22 (where J = connecting line between the lower edge of the radius and the tip of the 2nd finger, stretched; K = circumference in the area of ​​the metacarpal joints )
• Trunk (including neck, external genitals and breasts) = L × (M + N) × 0.703 (where L = from the top of the sternum to the top of the pubic bone; M = waist circumference at the level of the navel; N = chest size at the level of the nipples at Men and above the breasts in women)
• Thigh = O × (P + Q) × 0.508 (where O = upper edge of the greater trochanter to the lower edge of the patella ; P = circumference of a thigh below the perineum; Q = hip circumference at the level of the trochanters) and = W × (P + Q ) × 0.552 (where W = upper edge of the pubic bone to the lower edge of the patella)
• Lower leg = R × S × 1.4 (where R = from the sole of the foot to the lower edge of the patella; S = circumference at the lower edge of the patella)
• Feet = T × (U + V) × 1.04 (where T = length from heel to big toe; U = circumference at the level of the base of the little toe; V = narrowest circumference of the ankle)

Web links

• Pschyrembel Online : Body Surface . Automatic calculation after entering height and weight with various formulas

Individual evidence

1. ^ Eugene Lyman Fish, J. Ramser Crawford: How to Make the Periodic Health Examination , Macmillan Company , New York 1927, p. 345.
2. ^ Markus Daschner: Tabellarum nephrologicum , 3rd edition, Shaker Verlag , Aachen 2009, ISBN 978-3-8322-7967-7 , p. 67.
3. ^ Markus Daschner: Tabellarum nephrologicum , 3rd edition, Shaker Verlag, Aachen 2009, ISBN 978-3-8322-7967-7 , p. 67.
4. ↑ notmed.info
5. ^ MJ Müller: Nutritional medicine practice in the Google book search

literature

• E. Schlich, M. Schumm, M. Schlich: 3-D body scan as an anthropometric method for determining the specific body surface. In: Nutritional review. 57, 2010, pp. 178-183. (Abstract)
• RD Mosteller: Simplified calculation of body-surface area. In: N Engl J Med . 317, 1987, p. 1098. PMID 3657876 .
• EA Gehan, SL George: Estimation of human body surface area from height and weight. In: Cancer Chemother Rep. 54, 1970, pp. 225-235. PMID 5527019 .
• GB Haycock, GJ Schwartz, DH Wisotsky: Geometric method for measuring body surface area: A height-weight formula validated in infants, children and adults. In: J Pediatr. 93, 1978, pp. 62-66. PMID 650346 .
• D. DuBois, EF DuBois: A formula to estimate the approximate surface area if height and weight be known. In: Arch Intern Med . 17, 1916, pp. 863-871.
• E. Boyd: The growth of the surface area of ​​the human body . University of Minnesota Press, Minneapolis 1935.
• S. Fujimoto, T. Watanabe, A. Sakamoto, K. Yukawa, K. Morimoto: Studies on the physical surface area of ​​Japanese. 18. Calculation formulas in three stages over all ages. In: Nippon Eiseigaku Zasshi. 5, 1968, pp. 443-450.
• EH Livingston, S. Lee: Body surface area prediction in normal-weight and obese patients. In: American Journal of Physiology-Endocrinology and Metabolism . 281, 2001, pp. E586-E591.
• B Shuter, A. Aslani: Body surface area: Du bois and Du bois revisited. In: European Journal of Applied Physiology. 82, 3, 2000, pp. 250-254.

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !