Background: Flap operations are frequently performed in diabetic patients. Nevertheless, we could find no experimental study examining diabetes mellitus's effect on the flaps' survival. For this reason, we designed this study as a random-pattern skin-flap model of diabetic rats in 1999.
Methods: We used 72 rats weighing about 200 g each. The animals were divided into 2 groups, 1 experimental (diabetic) and 1 control (nondiabetic). Following their diabetic periods, we elevated the rats' modified McFarlane flaps and measured their viable flap areas.
Results: The mean percentage of the flap area surviving was 51.40% in the 2-week experimental group. It was 48.20% in the 4-week experimental group and 36.70% in the 8-week experimental group. The mean percentage of flap area surviving was 65.87% in the united control group (the total of all control groups). The mean surviving skin-flap area in the united control group was significantly higher than in the 4- and 8-week experimental groups. Moreover, the mean surviving flap area in the 8-week experimental group was significantly lower than in the 2-week and 4-week experimental groups.
Conclusions: Our study demonstrated that a 4-week diabetic duration for rats is sufficient to observe diabetes' deleterious effects on the flaps' viability. These effects were significantly established, however, after 8 weeks of diabetes. To obtain definitive results, at least 8 weeks of diabetic duration are preferred for similar studies.