The efficacy of sensory nerve coaptation in DIEP flap breast reconstruction - Preliminary results of a double-blind randomized controlled trial.

[BACKGROUND] Sensory nerve coaptation has great potential to restore sensation after autologous breast reconstruction. However, blinded and randomized studies are lacking. We therefore present the preliminary results of our ongoing double-blinded randomized controlled trial that compares sensory recovery of innervated versus non-innervated DIEP flaps.

[METHODS] Patients who underwent DIEP flap breast reconstruction between July 2019 and February 2022 were included and randomized. The anterior cutaneous branch of the second or third intercostal nerve was coapted. Pre- and postoperative sensory testing was performed with Semmes-Weinstein Monofilaments, Pressure Specified Sensory Device, and a thermostimulator, for tactile and temperature thresholds.

[RESULTS] This interim analysis comprised 41 patients contributing 29 innervated and 38 non-innervated breasts. At 24 months of follow-up, the mean monofilament value of the flap skin was lower in innervated than in non-innervated flaps (4.48 vs. 5.20, p = 0.003). Touch thresholds were lower the center of the innervated flaps (47.8 vs. 71.2 g/mm, p = 0.036), and heat pain was more often imperceptible in non-innervated flaps (42.1% vs. 10.3%, p = 0.004). No adverse events were associated with sensory nerve coaptation.

[CONCLUSIONS] These preliminary results indicate superior sensibility and recovery of protective sensation in innervated compared with non-innervated DIEP flaps. Although the results of the completed trial must be awaited to establish the full clinical impact, including highly anticipated quality of life outcomes, we encourage continuation of scientific and clinical efforts in this promising technique.