Synkinesis in Bell's palsy in a randomised controlled trial

Area of Science:

• Neurology
• Facial Nerve Research
• Clinical Trials

Background:

• Bell's palsy is a common cause of unilateral facial nerve paralysis.
• Synkinesis, involuntary facial muscle contractions, can develop as a sequela of facial nerve injury.
• Understanding synkinesis development is crucial for patient management and rehabilitation.

Purpose of the Study:

• To investigate the frequency, severity, and predictors of synkinesis in patients with Bell's palsy.
• To analyze gender differences in synkinesis development.
• To identify early indicators for predicting synkinesis.

Main Methods:

• Analysis of data from the Scandinavian Bell's palsy trial, a randomized controlled study.
• Inclusion of 829 patients, with a 12-month follow-up for 743 patients.
• Assessment of synkinesis frequency and severity using Sunnybrook scales at 12 months.

Main Results:

• Synkinesis was observed in 21.3% of patients at 12 months, with no significant gender difference.
• Moderate to severe synkinesis occurred in 6.6% of patients.
• Early indicators, including Sunnybrook composite score and voluntary movement symmetry at 1 month, effectively predicted synkinesis development.

Conclusions:

• Moderate to severe synkinesis affects a notable percentage of Bell's palsy patients.
• Synkinesis scores can increase between 6 and 12 months, necessitating long-term evaluation.
• Early assessment of facial nerve recovery using specific clinical scores can predict synkinesis risk.