Are there different degrees of injury?
Yes. Facial nerve injuries can be classified into three groups:
- First degree injury – the nerve is “concussed or bruised” and recovers within 8 weeks.
- Second degree injury – the nerve is more severely damaged but the nerve’s outer layer is still intact. It recovers at the rate of up to 1mm per day, with first signs of recovery usually at 4 months.
- Third degree injury – the nerve is severely damaged and requires surgical repair. Recovery from this is very slow and always incomplete. If the nerve is severed and not repaired in any way there will be no natural recovery and surgery will be required to help restore facial function.
The quality and duration of recovery is dependent on the severity of the initial injury. If the nerve has suffered nothing more than a mild trauma, recovery can be very fast, taking several days to several weeks. An “average” recovery is likely to take between a few weeks and a few months. The nerve regenerates at a rate of approximately 1-2 millimeters per day, and can continue to regenerate for 18 months, probably even longer. Improvement of appearance can continue beyond that time frame.
What happens once you have damaged your facial nerve?
When facial palsy initially occurs the affected side(s) of your face will feel and look floppy as there are no nerve signals telling the muscles to contract. Once your face starts to recover you will notice that:
- Muscles in some areas begin to work again earlier than other areas.
- In some areas you may notice different things about your face;
- The eye may seem smaller and the corner of the mouth may seem raised on the affected side.
- The cheek may feel tight and stiff. Don’t panic, you haven’t had a facial palsy on the other side.
- The cheek branches of the nerve tend to recover first but aren’t balanced out by the forehead and chin branches of the nerve which take longer to get working again. So the face muscles are unbalanced.
- As all the nerve branches recover you can help get balance back in the face with lots of slow, careful exercises in front of the mirror.
- At first movements may be asymmetrical and difficult but slow repetitive practice will eventually wake up your brain’s memory of how the movement used to work. This is a slow process but worth persevering with as small improvements add up to a big overall change.
- Exercises done at this stage must be done on a relaxed face and should concentrate on tiny, precise movements.
- Synkinesis can occur in the later stages of recovery.
- The more severe your nerve injury is the more likely it is that you will develop synkinesis.
- Synkinesis is a medical term that means ‘unwanted movement’. Having synkinesis means that different parts of the face move together outside your control.
- It happens because as the nerves begin their recovery, if one branch of the nerve is activated all the others join in to try and help, e.g. you want to smile and the eye shuts.
- This situation will improve as recovery continues as long as you get into the habit of stopping the unwanted movements from happening when you don’t want them to (your therapist will advise you how to achieve this).
- Synkinesis also means some facial muscles act against each other in a ‘tug of war’ which can stop parts of the face from moving even though the nerve has recovered. The affected muscles have to be gently re-taught when to move and when to stay relaxed and then this has to be practised over and over again. It is important not to practice incorrectly as this can make the situation worse.
- If you put too much effort into a facial movement it can spill over to stimulate all the nerves and you will get unwanted activity in other areas. This is why facial exercises have to be slow, gentle and careful, stopping just before you get unwanted activity.
- Techniques like looking in the mirror, touching your face and focused relaxation can all help your movement to become more refined.
- The amount of muscle effort needed to do these exercises is very low, only approximately 10%, pushing your face to work harder will not make you get better more quickly.
- One exercise done perfectly is better than many done with poor control.
What else may be a problem when you have facial palsy?
- A muscle in the ear (stapedius) can be affected causing sounds to appear louder on that side.
- Eating and drinking can be harder due to weakness of the cheek and lip seal.
- Food can collect in the affected cheek and be difficult to remove.
- Some people complain because they bite the inside of their cheek or lip.