Relationship between the ratio of length to width of the slender narrow pedicle and the survival area of the random flap

摘要

This study explored the relationship between the area of survival and the length/width ratio of slender narrow pedicles to random flaps to assess their clinical safety. Twenty-five pigs were randomly divided into five groups (n=5 in each group). The length/width ratios of the narrow pedicles in all five groups were 0/2(cm), 1 /2 (cm), 2/2 (cm), 3/2 (cm), and 4/2(cm) respectively, and these were created in five random flaps of different sizes on both sides of the back of each pig (Flap A [control]: 2cm×2cm; B: 3cm×3 cm; C: 4cm×4cm; D: 5cm×5 cm; and E: 6cm×6cm). Flap A was the “traditional” flap. All flaps survival areas were evaluated by general observation, intravenous fluorescent dye, blood flow ECT (Emission Computed Tomography) analyses, and histopathological examinations. The clinical course and pathological processes within the traditional flaps (Flap A) and the slender narrow pedicle flaps were consistent. An increasing flap area and a constant length/width ratio, or vice versa, preserved the area of graft survival. However, when the flap area reached a certain limit, the distal flap necrosis without decreasing the overall flap survival area in the same group; when the length/width ratio reached a certain limit, the distal flap necrosis with decreasing the overall flap survival area in the same group. The width of the pedicle can safely be significantly smaller than the width of the flap, and the flap pedicle can be designed to be slender. This type of pedicle facilitates flap rotation. However, there is a maximum flap survival area that the slender narrow pedicle can support.