Table 4.

Typical elements of facial training against facial synkinesis based on this review.

Element	Comment
EMG feedback exercises	Use of surface EMG for visual and/or auditory feedback of muscle activity simultaneously recorded from facial muscles/movement to be trained and facial muscles whose synkinetic activity should be reduced. Aim: Improvement of facial movement control while reducing synkinetic movements.
Mirror exercises	In front of a mirror: soft specific movement (for instance, showing teeth), holding the position for 5 sec, then relaxing; and trying not to close the eye. Aim: Improvement of facial movement control
Other active exercises	Soft specific movement (for instance, closing the eye), holding the position for 5 sec, then relaxing; Hand on synkinetic area (for instance, corner of the mouth) Aim: Improvement of facial movement control.
Mime therapy	Combination of physiotherapy and mime training Aim: Improving symmetry of the face both at rest and during movement, simultaneously controlling synkinesis.
Passive exercises, stretching and massage	Stretching individual muscles, holding 10–30 s Aim: Reducing muscle tension
Tactile or vibratory stimulation	Hands or devices are used for sensory stimulation of the facial skin Aim: Hypothesis: Sensory perception and sensory stimulation should promote motor skills. More studies are needed to confirm such an effect.
Combination with botulinum toxin injections	Botulinum toxin injection into facial muscle whose synkinetic activity should be reduced before starting the facial training Aim: Making the exercises easier for the patient; improvement of facial movement control
Other issues
Training session length	45–60 min, but also intensive training for 180 min established
Overall duration of the training	Typically over months, 10-day intensive training also established. Optimal duration not yet well studied.
Home exercises	If the patient shows improvement of facial movement control, home exercises can consolidate the therapeutic effect. 3–5 exercises twice daily. The additional effect of home training has still not been very well studied.
Telemedicine	Substitution of on-site training with therapist. The equivalence of telemedicine training has still not been very well studied.