Oral function in facial nerve palsy: a comparative analysis of flaccid and synkinetic palsy

Background: Facial nerve palsy (FNP) can have a profound impact on oral function and quality of life (QOL). However, the distinct challenges encountered by patients with flaccid compared with synkinetic facial movements have not been characterised. This study aimed to describe and compare speech, swallowing and QOL in patients with these 2 conditions. Methods: Patients with lower motor neurone FNP were recruited from the Sydney Facial Nerve Service. Their oral competence was measured using clinician- and patient-rated outcome measures. This included a consonant analysis of a recorded reading sample and a subjective intelligibility rating by the clinician and patient and 2 validated questionnaires, the Speech Handicap Index (SHI) and Oral Competence Questionnaire (OCQ). Results: Sixty-five participants were enrolled in the study (n=16 intact facial nerve function, prior to facial nerve sacrifice surgery, n=31 synkinetic FNP and n=18 flaccid FNP). The flaccid FNP group presented with more speech errors within each consonant group (p<0.001), poorer intelligibility in clinician and patient ratings (p<0.001 and p=0.01, respectively) and in the OCQ responses (p=0.01). No significant difference was observed in the SHI between the synkinetic and flaccid groups. Conclusions: Flaccid and synkinetic FNP are 2 distinct conditions, presenting with differing characteristics and requiring different treatment pathways. These findings suggest that patients with flaccid FNP present with poorer functional outcomes in swallowing and speech-related QOL.