Functional upgrading of partially recovered facial palsy by cross-face nerve grafting with distal end-to-side neurorrhaphy

Background: Cross-face nerve grafting combined with functional muscle transplantation has become the standard in reconstructing an emotionally controlled smile in complete irreversible facial palsy. A special problem exists in incomplete or partially recovered facial palsies, when the little existing function should be preserved but the existing function alone is clinically insufficient. Methods: In this situation, cross-face nerve grafting performed by means of end-to-end coaptation to a zygomatic branch of the healthy side and by end-to-side neurorrhaphy to a corresponding branch of the incompletely paralyzed side is proposed to upgrade smile function on the latter side and contribute to more static and dynamic overall symmetry. The interposition nerve graft is set in overlength to preserve the possibility of a later muscle transplantation in case of unsatisfying functional result through the additional neuronal input. The authors have used this concept in seven patients with irreversible partial facial palsy. Three cases have a sufficiently long follow-rip to be presented here. Outcome was objectively quantified with three-dimensional video analysis of facial movements. Results: In all three cases, functional improvement and a positive effect on the static and dynamic symmetry of the face could be measured. None of the patients was disappointed by the smile function achieved or wanted to undergo additional muscle transplantation. Conclusion: On the basis of these first clinical experiences, the authors recommend cross-face nerve grafting with overlength and a distal end-to-side neurorrhaphy in patients with irreversible incomplete facial palsy affecting the smile.