The effect of twisting on single and double based perforator flap viability: An experimental study in rats

In this study, the histological and vital effects of rotation on multiple and single based perforator flaps were evaluated. A 6 cm × 6 cm abdominal perforator flap model was used on 80 male rats; half of these received a single‐pedicled flap, and the other half double‐pedicled. The flaps of control subgroups were raised and sutured without rotation. In rotation subgroups 90‐, 180‐, 270‐degree rotations were performed, and rotation effects on flap viability and histological changes were analyzed. Among single‐ and double‐pedicled perforator flaps, respectively, mean survival area was 12.59 cm² and 27.84 cm² in non‐rotated subgroups, 12.49 cm² and 17.06 cm² in 90‐degree rotation subgroups, 5.96 cm² and 9.96 cm² in 180‐degree rotation subgroups, and 1.45 cm² and 1.70 cm² in 270‐degree rotation subgroups. While survival areas of double‐ and single‐pedicled perforator flaps with the same rotation degree showed no statistically significant difference, non‐rotated double‐pedicled perforator flaps had a statistically larger survival area compared to single‐pedicled perforator flap (P = 0.001). In the single‐pedicled flap group, there were no statistical differences between survival flap areas of the non‐rotated subgroup and the 90‐ and 180‐degree rotation subgroups (P > 0.05), but the non‐rotated subgroup had a statistically larger survival area compared to the 270‐degree rotation subgroup (P = 0.003). In double‐pedicled perforator flap group, the control subgroup had a statistically larger flap survival area compared to 90‐degree, 180‐degree, and 270‐degree rotation subgroups (P = 0.004, P = 0.002, P = 0.001). Degenerative histological changes gradually increased in correlation with the rotation angle in both single‐ and double‐pedicled groups. When double‐ and single‐pedicled groups were compared; degenerative histology score displayed no statistical difference between control subgroups and rotated subgroups (P > 0.05). In this rat abdominal propeller perforator flap model, we found that double perforators without pedicle rotation could support larger flap survival when compared to the single pedicle. However, double perforators did not cause an increase of survival area when pedicles were rotated. In the single‐pedicled perforator flap, the flap survival area did not significantly decrease until 180‐degree pedicle rotation. In the double‐pedicled perforator flap, the flap survival area decreased when the degree of rotation increased. The degenerative changes increased in correlation with the rotation degree in both single‐ and double‐pedicled perforator flaps. © 2014 Wiley Periodicals, Inc. Microsurgery 34:464–469, 2014.