Fat necrosis in free and pedicled TRAM flaps.

One purported advantage of the free transverse rectus abdominis musculocutaneous (TRAM) flap for breast reconstruction is that, compared with the conventional TRAM flap, it has a better blood supply and therefore a lower incidence of fat necrosis. We tested this claim by reviewing the incidence of fat necrosis, both clinically and mammographically, in a group of 110 patients with 116 TRAM flap breast reconstructions who had undergone mammography of their reconstructed breasts. Of the 49 breasts reconstructed with free TRAM flaps, 4 (8.2 percent) had clinically evident fat necrosis, and 1 (2.0 percent) had fat necrosis that was detectable by mammography. Of the 67 breasts reconstructed with conventional TRAM flaps, 18 (26.9 percent) had clinically detectable fat necrosis, and 9 (13.4 percent) had fat necrosis that was detectable mammographically. Both of these differences were statistically significant (p = 0.0113 for clinical fat necrosis; p = 0.031 for mammographic fat necrosis). Fat necrosis was more common in patients who were obese or had a history of smoking, but neither association was statistically significant. We conclude that the use of the free TRAM flap reduces the incidence of fat necrosis in the reconstructed breast.