The goal of this observational cross-sectional study is to investigate whether the severity of facial dysfunction is associated with psychological distress in patients with unilateral facial palsy.

The main questions it aims to answer are:

• Is there a significant relationship between the degree of facial muscle dysfunction (as measured by Sunnybrook Facial Grading Scale and EMG parameters) and levels of anxiety and depression (as measured by HADS)?
• Does reduced facial function correlate with lower self-esteem levels (as measured by the Arabic version of the Single-Item Self-Esteem Scale)?

Researcher will assess and analyze the correlation between facial motor impairment and psychological outcomes to determine whether greater functional impairment is associated with increased psychological distress.

Participants will:

• Undergo clinical assessment using the Sunnybrook Facial Grading Scale to evaluate facial nerve function
• Receive electrophysiological evaluation using surface electromyography (sEMG) to measure muscle activity
• Complete standardized questionnaires including the Hospital Anxiety and Depression Scale (HADS) and the Arabic Single-Item Self-Esteem Scale (A-SISE)

Facial palsy represents a complex neurological condition with multifactorial consequences that extend beyond motor dysfunction to encompass significant psychosocial impairment. While the physical manifestations of facial nerve dysfunction are well characterized, the psychological sequelae particularly anxiety, depression, and diminished self-esteem remain under-investigated in relation to objective measures of functional severity. Existing literature has largely relied on subjective or isolated assessment approaches, with limited integration of clinical grading systems and electrophysiological quantification.

This study aims to systematically examine the association between the severity of facial dysfunction and psychological distress using a multidimensional assessment framework. Objective evaluation of facial motor function will be conducted using standardized clinical grading, complemented by electrophysiological measurements to quantify muscle activity and neuromuscular performance. Psychological outcomes will be assessed using validated instruments that capture core domains of emotional well-being, including anxiety, depressive symptoms, and global self-esteem.

Facial motor function will be assessed using the Sunnybrook Facial Grading Scale (SFGS), a validated and widely used clinical tool that evaluates resting symmetry, voluntary movement, and synkinesis. The composite score derived from this scale provides a quantitative measure of overall facial nerve function, allowing for sensitive detection of varying degrees of impairment across facial regions.

To complement clinical evaluation, electrophysiological assessment will be conducted using surface electromyography (sEMG) to objectively quantify muscle activity in key facial muscles. sEMG recordings will be obtained from standardized electrode placement sites over functionally relevant muscles (e.g., frontalis, orbicularis oculi, and orbicularis oris). Signal analysis will include parameters such as amplitude (e.g., root mean square [RMS]) to reflect motor unit recruitment and neuromuscular activation. This quantitative approach provides objective insight into the degree of muscle involvement and functional integrity, enhancing the precision of facial function assessment.

Psychological outcomes will be evaluated using validated self-report instruments. The Hospital Anxiety and Depression Scale (HADS) will be used to assess levels of anxiety and depressive symptoms through its two subscales, providing a reliable measure of psychological distress in clinical populations. Additionally, global self-esteem will be assessed using the Arabic version of the Single-Item Self-Esteem Scale (A-SISE), a brief yet validated measure designed to capture the individual's overall perception of self-worth.

A key strength of this study lies in its integrative design, which combines clinical, electrophysiological, and patient-reported outcome measures within a single analytical model. This approach is intended to address an existing gap in the literature regarding the extent to which objectively measured facial impairment correlates with psychological burden.

The findings of this study are expected to provide clinically relevant insights into the interplay between functional impairment and mental health in patients with facial palsy. In turn, this may contribute to improved risk stratification, early identification of vulnerable patients, and the development of comprehensive rehabilitation strategies that incorporate both physical and psychosocial dimensions of care.

Inclusion Criteria:

• Patients with unilateral idiopathic Bell's palsy confirmed by nerve conduction studies (NCS) will be included.
• The age of patients ranged from 25 to 50 years.
• The duration of Bell's palsy ranged from three months to two years.
• Patients with a body mass index (BMI) less than 30 kg/m² will be included.
• Only patients who were able to comprehend and complete questionnaires will be included in the study.

Exclusion Criteria:

• History of recurrent facial palsy or bilateral facial nerve involvement.
• Presence of other neurological disorders unrelated to facial palsy affecting the face (e.g., stroke, multiple sclerosis).
• A current diagnosis of psychiatric illness prior to the onset of facial palsy.
• Cognitive impairment preventing valid completion of assessments.
• Sleep disorders.
• Diabetes mellitus.

Eighty-five patients of both sexes with unilateral idiopathic Bell's palsy will be participate in this study. The patients diagnosis as having Bell's palsy based on careful clinical examination by a neurologist. The diagnosis will be confirmed by nerve conduction studies. Patients will be recruited from the outpatient clinic of the Faculty of Physical Therapy, Hours University.