Syn = Abnormal
Kinesis = Movement
So how is this abnormal movement (synkinesis) created in facial palsy?
When the nerve is compressed in the acute phase of a facial palsy due to either inflammation, surgery, or tumours; it is possible that some of the axons or “wires” will be severed.
Our peripheral nerves have the capacity to regrow and do so at the rate of 1mm per day. In the process of regrowing, sometimes the nerves get crossed and end up going to a different muscle than they did originally (see diagram below). The left side of the face is normal and the right side depicts synkinesis.
A nerve that originally went to the eye, for example, is now going to the mouth. The brain still thinks it’s talking to the eye, but now the mouth is reacting. This is how movements become connected so that when a person with synkinesis blinks, their mouth might also move. Through hard work and the help of a trained facial therapist, it is possible to create a new pathway using the principles of neuroplasticity. For a great reference on neuroplasticity see Norman Doidge’s book The Brain that Changes Itself.