Twenty-seven free transverse rectus abdominis musculocutaneous (TRAM) and 16 pedicled TRAM flap breast reconstruction patients were studied for 7 to 41 months (mean, 23 months) postoperatively to compare abdominal sequelae after these two operations. The patient groups were demographically similar; mean age was 47 years in both groups. Subjective grading of the results was similar in both groups. The incidence of minor lower abdominal bulges was higher (44%, 7/16) in the pedicled group than in the free TRAM flap group (4%, 1/27). No hernias were found. Delayed healing of the abdominal scar occurred in 3 free TRAM flap and 1 pedicled TRAM flap patients. Two free TRAM flap (8%) and 7 pedicled TRAM (44%) flap patients had minor edge necrosis of the breast. Trunk strength was tested using an isokinetic device (Lido Multi Joint II), and peak torque for flexion (mean, 111 Nm ± 25 Nm in the free TRAM flap group and 123 Nm ± 28 Nm in the pedicled TRAM flap group) and extension (mean, 144 Nm ± 38 Nm and 167 Nm ± 45 Nm) were measured. No statistical differences occurred between these groups. Sit-up performance was tested and graded from 1 to 6. Both groups performed equally (4.8 and 4.8) and within normal values for this age group. Ultrasonography of the rectus muscles revealed that in the free TRAM flap group, the rectus muscle of the operated side was significantly thinner (cranial segment 6.8 mm vs. 7.8 mm, p