BACKGROUND: The transverse rectus abdominis musculocutaneous (TRAM) flap is widely used in breast reconstruction. However, morbidity with its pedicled form has resulted in a high incidence of complications. The authors conducted a study of the pedicled TRAM flap procedure in 35 female Wistar rats based on the left deep inferior epigastric vessel, which was nondominant. METHODS: In all the rats, the flap was divided into four areas: area 1, the skin on the left rectus abdominis muscle pedicle; area 2, the skin contralateral to the midline, opposite of the left rectus abdominis muscle pedicle; and areas 3 and 4, the skin lateral to areas 1 and 2, respectively. The occurrence, percentage, and distribution of necrosis on the TRAM flap surface were determined. RESULTS: Necrosis was observed at four statistically distinct and significant levels, distributed in the four different areas as follows: area 1, 9 percent; area 2, 37 percent; area 3, 74 percent; and area 4, 100 percent (p < 0.001). The median proportion of necrosed flap surface was 15 percent (range, 2 to 42 percent). CONCLUSIONS: The determination of necrosis allowed us to identify three distinct levels of necrosis: area 4 with the highest scores, area 3 with intermediate scores, and areas 1 and 2 with the lowest scores (p < 0.001). Areas 1 and 2 of the TRAM flap surface had less incidence of necrosis, contrary to the lateral areas 3 and 4, in which cutaneous necrosis was found to be more significant.
BACKGROUND: The transverse rectus abdominis musculocutaneous (TRAM) flap is widely used in breast reconstruction. However, morbidity with its pedicled form has resulted in a high incidence of complications. The authors conducted a study of the pedicled TRAM flap procedure in 35 female Wistar rats based on the left deep inferior epigastric vessel, which was nondominant. METHODS: In all the rats, the flap was divided into four areas: area 1, the skin on the left rectus abdominis muscle pedicle; area 2, the skin contralateral to the midline, opposite of the left rectus abdominis muscle pedicle; and areas 3 and 4, the skin lateral to areas 1 and 2, respectively. The occurrence, percentage, and distribution of necrosis on the TRAM flap surface were determined. RESULTS:Necrosis was observed at four statistically distinct and significant levels, distributed in the four different areas as follows: area 1, 9 percent; area 2, 37 percent; area 3, 74 percent; and area 4, 100 percent (p < 0.001). The median proportion of necrosed flap surface was 15 percent (range, 2 to 42 percent). CONCLUSIONS: The determination of necrosis allowed us to identify three distinct levels of necrosis: area 4 with the highest scores, area 3 with intermediate scores, and areas 1 and 2 with the lowest scores (p < 0.001). Areas 1 and 2 of the TRAM flap surface had less incidence of necrosis, contrary to the lateral areas 3 and 4, in which cutaneous necrosis was found to be more significant.