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A Rule of Thumb for Evaluating Surface Areas of Chronic Wounds
Zexin Yao1, Suiping He, Mengru Pang
1In the Department of Public Health, Guangdong Pharmaceutical University, Guangzhou, China, Zexin Yao, MPH; and Suiping He, MPH, are postgraduate students. In the Department of Burn and Plastic Surgery, General Hospital of Southern Theater Command of PLA, Guangzhou, Mengru Pang, MM; Xiaoxuan Lei, MM; Cuiwen Wu, MM; Enqing Lin, MM; Zhilong Cao, MM; and Wencai Jiang, MM, are postgraduate students. Xiaobing Fu, MD, PhD, is Professor of Wound Healing, College of Life Sciences, PLA General Hospital, PLA Medical College, Beijing. Biao Cheng, MD, PhD, is Professor of Wound Healing, Department of Public Health, Guangdong Pharmaceutical University. Acknowledgments: This study was supported by grants from the National Natural Science Foundation of China (81272105 and 81671924), the National Key Research and Development Plan of China (2017YFC1103301), the Science and Technology Key Project of Guangdong Province (2014B020212010), the Science and Technology Planning Project of Guangdong Province of China (2015B020233012), and the Military Medical Innovation Special Projects (18CXZ029). The authors have disclosed no other financial relationships related to this article. Submitted April 24, 2020; accepted in revised form May 26, 2020.
Background:
Rapid estimation of the area of chronic wounds is clinically important. A simple method using the thumb was investigated for universal physical measurement, particularly of small and multiple wounds; the thumb surface area (TSA) was then compared with the total body surface area (TBSA).
Methods:
A cross-sectional observational study and random sampling were used to obtain the characteristics of 343 participants. Data related to handprint surface area of the thumb and palm were collected using a scanner and laptop and assessed using image software. The TSA as a percentage of TBSA was confirmed based on the traditional rule that regards palmar surface area as 1% of TBSA. Information on factors potentially influencing measurement was gathered with questionnaires to analyze correlations.
Results:
The left and right TSAs were on average 4.27% and 4.28%, respectively, of the palmar surface area for all participants. Multiple linear regression analysis found that male and older participants had higher TSA:TBSA proportions (sex, P = .0020; age, P < .0001). The TSA:TBSA proportion increased by age for both males (by age group, 0.0418%, 0.0426%, 0.0432%, and 0.0460%, respectively) and females (0.0400%, 0.0409%, 0.0427%, and 0.0430%, respectively).
Conclusions:
Thumb size is relatively stable in relation to TBSA, lending itself to a universal method for estimating the size of chronic wounds as a percentage of TBSA. It therefore represents a convenient physical measurement for assessing the area of burns and other wounds.
