Triple nerve transfers for the management of early unilateral facial palsy.

Background: Early onset facial paralysis is usually managed with cross-face nerve grafts, however the low number of axons that reach the target muscle may result in weakness or failure. Multiple-source innervation, or 'supercharging', seeks to combine the advantages of different donor nerves while minimizing their weaknesses. We propose a combination of cross-face nerve grafts with local extra-facial nerve transfers to achieve earlier facial reanimation in our patients.

Methods: A retrospective cohort including all patients with early unilateral facial palsy (<12 months evolution) who underwent triple nerve transfer between 2019 and 2021 was conducted. We performed single-stage procedure including zygomatic-to-zygomatic and buccal-to-buccal cross-face grafts, a nerve-to-masseter to bucozygomatic trunk transfer, and a mini-hypoglossal to marginal branch transfer. Results were evaluated using the clinician-graded facial function scale (eFACE).

Results: Fifteen patients were included (eight females, seven males), mean age at the time of surgery was 48.9 ± 13.3 years. Palsy was right-sided in eight cases. The mean time from palsy onset to surgery was 5.5 ± 2.8 months. Patients showed improvement in static (70.8 ± 21.9 vs. 84.15 ± 6.68, p = 0.002) and dynamic scores (20 ± 16.32 vs. 74.23 ± 7.46, p < 0.001), as well as periocular (57.33 ± 15.23 vs. 74 ± 7.18, p = 0.007), smile (54.73 ± 11.93 vs. 85.62 ± 3.86, p < 0.001), mid-face (46.33 ± 18.04 vs. 95 ± 7.21, p < 0.001) and lower face scores (67.4 ± 1.55 vs. 90.31 ± 7.54, p < 0.001).

Conclusion: The triple nerve transfer technique using cross-face nerve grafts, the nerve-to-masseter, and the hypoglossal nerve, is an effective and reproducible technique to obtain middle and lower face reanimation in cases of early facial palsy.