Effects of pedicle torsion on dynamic perforasome survival in a multiterritory perforator flap model: An experimental study.

Background: Necrosis of propeller flaps is a problem in clinical practice. This study was performed to investigate the effects of pedicle torsion on dynamic perforasome survival using a multiterritory perforator flap model in rats.

Methods: Intercostal artery perforator flaps (IC flaps) containing two adjacent dynamic perforasomes were applied to both sides of the dorsum in 15 rats. The IC vessels were dissected carefully under 10 × magnification. A 360° arc of pedicle torsion was applied to the right IC flaps, which comprised the rotary group. Left IC flaps were used as controls. Flap perfusion, viability, and angiography were compared between the two groups.

Results: Sodium fluorescein angiography showed that there was blood supply to the flap in both groups on postoperative day (POD) 1, and laser Doppler images indicated that flap perfusion increased daily after surgery. The differences in perfusion of dynamic perforasomes between the two groups were not significant. The mean survival rate of the rotary group was not significantly different from that of the control group (98.94 ± 1.24% versus 99.03 ± 1.86%, respectively, p > 0.05) on POD 7. Angiography showed that dilated choke vessels connected the three perforasomes in both groups.

Conclusions: The 360° arc of pedicle torsion had no detrimental effect on dynamic perforasome perfusion or survival in a multiterritory perforator flap model after meticulous surgical dissection of the pedicle in this study. The dilated choke vessel connected adjacent perforasomes, and the dynamic perforasome survival still adhered to the perforasome theory after pedicle torsion.