Medial Sural Artery Perforator Flap: A Middle Ground Between Anterolateral Thigh and Radial Forearm Flaps.

Abstract

The medial sural artery perforator (MSAP) flap has gained popularity in head and neck reconstruction primarily as a less morbid alternative to the radial forearm free flap (RFFF). However, no direct comparison of thickness exists among the MSAP, RFFF, and anterolateral thigh (ALT) flaps, which together represent the commonly utilized nonosseus-free flaps in head and neck reconstruction. Thus, this study aimed to compare these flap sites and identify predictors of thickness that will aid in reconstructive surgical planning. Cross-sectional study. Tertiary referral hospital. The thickness of skin and subcutaneous tissue at the RFFF, MSAP, and ALT donor sites were measured in 54 adult patients using Doppler ultrasound. General linear models were generated to identify predictors of flap thickness. The mean thickness of the RFFF, MSAP, and ALT flaps was 3.8 ± 2.2 mm, 7.4 ± 3.8 mm, and 9.6 ± 4.7 mm. Body mass index (BMI) was the only statistically significant contributing factor (p < .0001, coefficient: 0.15) for the RFFF. MSAP was affected by age (p = .006, coefficient = 0.06), female gender (p < .0001, coefficient = 3.2), and BMI (p < .001, coefficient = 0.25), while the ALT was affected by female gender (p = .0005, coefficient = 3.3) and BMI (p < .0001, coefficient = 0.35). Thus, the ratio of increase for flap thickness with respect to BMI is 3:5:7 for the RFFF, MSAP, and ALT flaps, respectively. The MSAP is about twice the thickness of the RFFF and 2 mm thinner than the ALT; however, 22% of patients had thicker MSAP than ALT flaps. As the strongest predictors of flap thickness, female gender, and BMI may be taken into consideration during surgical planning for reconstruction.