Sensory reinnervation of autologous tissue TRAM flaps after breast reconstruction

The use of the transverse rectus abdominis musculocutaneous (TRAM) flap has come to the forefront for breast reconstruction following mastectomy. Despite our ability to create surgically a supple breast mound, simulate the nipple with local skin flaps, and pigment the skin to create an areola, one of the last drawbacks has been the reestablishment of normal sensation. Some patients have anecdotally reported some sensory return in the reconstructed breast mound. We sought to quantitate the pattern of sensory return in TRAM flaps in 24 patients to identify factors that favor sensory reinnervation of the flap. Patients were recalled for sensory testing after unilateral or bilateral breast reconstruction following mastectomy for cancer or premalignant mastopathy. The interval from surgery varied from 3 to 41 months. Sensation was evaluated using the Semmes-Weinstein monofilament test, hot/cold recognition, and vibratory sensation measured in 16 segments of the reconstructed breast mound and compared to the opposite, unoperated breast or to volunteer controls. Thirty-four flaps were evaluated. The Semmes-Weinstein measurements demonstrated measurable sensation in 32 of 34 flaps with 2 flaps developing sensation equal to the control unoperated breast. The return of hot recognition occurred in 21 of 34 flaps, cold recognition in 22 of 34 flaps, and vibratory sensation in 26 of 34 flaps. Our findings suggest that excellent sensory return occurs in the majority of patients via nerve ingrowth into the flap from the mastectomy bed. It would appear that a natural breast reconstruction with some sensation can be a reality for the majority of patients in the absence of additional complex surgical maneuvers such as nerve preservation or nerve-nerve coaptation.