Facial synkinesis is a condition in which certain facial muscles move unintentionally while you're trying to make a different expression — such as your eye closing when you smile. It often develops after facial nerve injury or inflammation, such as Bell’s palsy.
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What Is Synkinesis?
Facial synkinesis is a condition in which certain facial muscles move unintentionally while you're trying to make a different expression, such as your eye closing when you smile.It often develops after facial nerve injury or inflammation, such as Bell's palsy.
As the nerve recovers, it may accidentally reconnect to the wrong muscle groups. This mix-up confuses the signals from your brain to your facial muscles, so that muscles end up moving when they shouldn’t.
Think of it as your brain sending a message to your mouth to smile, but another muscle “eavesdrops” and reacts as well — even though it wasn’t invited to the party.
What are the types of synkinesis?
The most common types of facial synkinesis are:
- Ocular-oral synkinesis — When blinking or closing an eye causes the mouth muscles to twitch or pull.
- Oral-ocular synkinesis — When smiling or puckering your lips causes your eyes to narrow or close.
Other common synkinetic facial movements include:
- Cheek lifting or dimpling when you shut your eyes tightly.
- Eyes closing, tearing, or twitching when you’re chewing or eating.
- Eyelids closing or twitching when you raise your eyebrows.
- Lips moving or twitching when you raise your eyebrows.
- Neck muscles tightening when you sing, talk, or whistle.
What causes synkinesis?
Facial synkinesis is caused when nerve fibers (known as axons) grow back in a disorganized way after a significant trauma to the facial nerve.
If the nerve is only mildly affected, such as in a mild case of Bell’s palsy, the axons are temporarily blocked, but not harmed. This is called neuropraxia. People with neuropraxia typically do not develop synkinesis. But if the axons are damaged and then regenerate incorrectly, synkinesis can occur.
Synkinesis risk factors
You’re at higher risk of facial synkinesis if you’ve had:
- Bell’s palsy.
- Ramsay Hunt syndrome.
- Lyme disease causing facial paralysis.
- Facial nerve surgery, such as vestibular schwannoma removal, removal of parotid tumor, or trauma.
- Nerve grafting or nerve repair surgery.
These conditions may damage facial nerve fibers, which may lead to aberrant (abnormal) regeneration as they heal. Regenerating nerve fibers may reconnect to unintended muscles, leading to involuntary contractions at the same time as voluntary movements.
Complications of synkinesis
When synkinesis is left untreated, it can lead to a range of physical, functional, and emotional issues that can worsen over time.
Functional/physical impact
- Involuntary muscle movements — Patients may experience unwanted contractions, like eye closure when smiling or lip pulling when blinking. This can make everyday tasks like eating, speaking, or smiling more difficult.
- Muscle imbalance and tightness — Overactive muscles can become stiff due to too much muscle tone, leading to discomfort and a sensation of facial tightness.
- Reduced facial symmetry — As synkinesis progresses, facial expressions may become uneven or distorted, affecting both appearance and communication.
Psychosocial impact
- Lower quality of life — Untreated synkinesis can lead to emotional distress, frustration, and social isolation.
- Self-consciousness and social withdrawal — The visible effects of synkinesis can make people feel embarrassed or anxious in social settings.
Diagnostic/treatment impacts
Treatments are most effective when started early.
Early diagnosis and personalized therapy offer the best chance for meaningful recovery.
How common is synkinesis?
According to the National Institutes of Health (NIH), facial synkinesis affects about 30% of patients after acute peripheral facial nerve palsy, including Bell’s palsy. Facial synkinesis occurs in 10% to 20% of children after acute facial palsy.
What Are the Signs and Symptoms of Synkinesis?
Common symptoms of synkinesis include:
- Increased muscle tightness in the face — Facial muscles on the affected side become too tight, making them difficult to move compared to those on the unaffected side.
- Linked facial movements — Because the neural signals from the brain to the face have become confused, an attempt to move one muscle may result in inappropriate activation of other muscles. For example, smiling might cause your eye to close. These linked movements might persist long-term.
- Muscle spasms — Some patients with synkinesis complain of muscle spasms, particularly around the eye and in the lower face/neck.
When should I see a doctor about my synkinesis symptoms?
Contact your health care provider if you notice any involuntary facial movements that happen at the same time as intentional ones. This is especially important if symptoms appear after you've recovered from a facial nerve issue, such as Bell's palsy or Ramsay Hunt syndrome, or facial nerve surgery.
How Do You Diagnose Synkinesis?
Your doctor will take your medical history and ask you about your history of facial palsy. They will conduct a physical exam and may use a patient questionnaire to quantify your symptoms.
The following tests might be needed:
- Electromyography — Can confirm synkinetic muscle interaction during voluntary facial movements.
- Hearing tests — Some conditions can affect both the facial nerve and your hearing.
- Standardized photo series — Photos may be taken for your medical record, to help track your progress over time.
Synkinesis can occur for several reasons, and a comprehensive clinical assessment is essential to ensure a proper diagnosis.
How Do You Treat Synkinesis?
Common synkinesis treatment options include:
Physical therapy/facial training therapy
Facial nerve physical therapy focuses on retraining the coordination of appropriate facial muscle movements. Other related treatments include mirror therapy, relaxation exercises, and home self-massage.
Chemical denervation (Botox®)
Botox may be used on synkinetic muscles by itself or combined with physical therapy/facial training therapy. Botox treats synkinesis by reducing inappropriate muscle activity, reducing uncomfortable muscle tension, and balancing the face to achieve better facial symmetry.
Surgery
Surgery is usually a second- or third-line treatment reserved for synkinesis that has failed to respond to physical therapy and Botox.
Surgical treatment options for synkinesis may include:
- DAO myectomy.
- Ocular myectomy.
- Platysmectomy.
- Brow lifting.
- Upper blepharoplasty.
- Selective denervation.
- Cross-facial nerve grafting.
- Gracilis free muscle transfer.
