Comparison of venous drainage in flow-through and conventional dorsalis pedis flaps for repair of dorsal foot defects.

Inadequate venous drainage can lead to congestion and necrosis of flaps used in the repair of defects, thereby elevating the risk of flap failure. In this study, we sought to test the hypothesis that the venous drainage was better in flow-through flaps than in conventional dorsalis pedis free flaps used in the repair of dorsal foot defects. In this retrospective study, we investigated the data of 14 patients who underwent repair with flow-through flaps (n = 7) or conventional flaps (n = 7) for dorsal foot defects, between January 2007 and December 2013. The defects ranged from 6.2 × 11 cm to 9.5 × 16 cm in size. The donor sites were resurfaced using full-thickness free-skin grafts, and after transfer, the flaps were evaluated for postoperative congestion, surviving area, and sensory function. The results showed that the operative time was significantly longer for flow-through flaps than for conventional flaps (6.4 ± 1.7 h vs. 4.3 ± 1.2 h, P = 0.020), mainly due to additional dissection of the first dorsal metatarsal artery required in the case of the former. Necrosis was observed in the case of 4 conventional flaps, but not in the case of flow-through flaps. The flow-through flaps showed significantly lower incidence of congestion and higher survival area proportion than the conventional flaps (P < 0.05). The flow-through dorsalis pedis flaps have the advantages of lower incidence of necrosis and congestion and better survival over the conventional flaps in the repair of dorsal foot defects, and absence of additional morbidities, but required a longer operative time than conventional flaps.