Grade

Definition

I

Normal symmetrical function in all areas

II

Slight weakness noticeable only on close inspection
Complete eye closure with minimal effort
Slight asymmetry of smile with maximal effort
Synkinesis barely noticeable, contracture, or spasm absent

III

Obvious weakness, but not disfiguring
May not be able to lift eyebrow
Complete eye closure and strong but asymmetrical mouth movement
                                                                           with maximal effort
Obvious, but not disfiguring synkinesis, mass movement or spasm

IV

Obvious disfiguring weakness
Inability to lift brow
Incomplete eye closure and asymmetry of mouth with maximal effort
Severe synkinesis, mass movement, spasm

V

Motion barely perceptible
Incomplete eye closure, slight movement corner mouth
Synkinesis, contracture, and spasm usually absent

VI

No movement, loss of tone, no synkinesis, contracture, or spasm