Facial nerve in foetal cadavers: An anatomical study with clinical relevance

Introduction: Facial nerve paralysis is a major complication of parotid surgery and is widely reported. Little attention is paid to the facial nerve trunk in children. The facial nerve trunk in children and infants can be easily injured since they lie close to the surface. The present study therefore intends to describe the variability in the facial nerve trunk and its branching pattern in foetuses. Methods: The study was done bilaterally in 30 formalin-fixed foetuses (15 females, 15 males), age ranging from 21.0 to 35.5 weeks of gestation. The length of the facial nerve trunk was measured and bifurcation and trifurcation of the trunk was examined. Variability in the branching pattern was also noted. Results: The most common facial nerve trunk branching type was bifurcation (53.33%), followed by trifurcation (33.33%). Multiple branching of the facial nerve was also observed in 13.34% of the cases. Other variations related to the facial nerve were also noted. The mean length of the facial nerve trunk was 7.15 ± 2.12 mm. There was no significant difference between the right and left sides and in case of males and female foetuses. Conclusion: Facial nerve injury during parotid surgery is a main cause of paediatric facial paralysis. The length of the facial nerve trunk therefore must be accurately known in any surgical procedure planned in the area. The main furcation of the facial nerve should also receive special attention.