Reciprocal Dominance of the Anterolateral and Anteromedial Thigh Flap Perforator Anatomy

Abstract

When anterolateral thigh (ALT) perforators are inadequate, exploration of the contralateral thigh may be required. If anteromedial thigh (AMT) perforators were useable in these instances, harvest could proceed from a single donor site. A prospective cohort study was performed examining 100 consecutive thighs. Anterolateral and anteromedial thigh skin territories were surgically explored, and perforator size and number were documented. The relationship between ALT and AMT size and number was examined using Fisher exact test, logistic regression, and linear regression. Patients with small or no ALT perforators usually had a large AMT perforator. Patients with large or medium ALT perforators usually had medium or small AMT perforators (P = 0.029). Patients with small or no ALT perforators had a 6-fold increased chance of large/medium AMT perforators (odds ratio, 6.18; 95% confidence interval [CI], 1.23-30.91; P = 0.026). Patients without ALT perforators usually had 1 or more AMT perforators. Patients with 3 ALT perforators usually had no AMT perforators (P < 0.001). Patients with 1 or fewer ALT perforators had a 4-fold increased chance of an AMT perforator (odds ratio, 3.77; 95% CI, 1.34-10.65; P = 0.012). After assigning numeric values to perforators based on size, the total scores for ALT and AMT regions were analyzed using a linear regression model. Lower ALT perforator scores were significantly related to higher AMT scores (slope, -0.33; 95% CI, -0.46 to -0.20; P < 0.001). The Spearman test showed a similar relationship (ρ = -0.43, P < 0.001). There is an inverse relationship between size and number of ALT and AMT perforators, that is, when ALT perforators are inadequate, AMT perforators are typically useable.