Synkinesis refers to a movement disorder in which there is involuntary co-movement of muscles or muscle groups not involved in the intended movement.
Pathophysiology
The development of synkinesias is mainly based on faulty reinnervation after nerve damage. After axonal injury, nonspecific sprouting of nerve fibers occurs during regeneration, so that motor end organs are innervated incorrectly. This results in a single cortical impulse activating several muscle groups simultaneously.
Diagnosis
Diagnosis is primarily clinical and is based on observing characteristic co-movements during targeted voluntary actions. In addition, an electromyography (EMG) examination can also be performed for diagnostic purposes[^1].