Nonflaccid Facial Palsy: 15-30% Risk After Bell’s Palsy

“Nonflaccid facial paralysis is a spectrum of hypokinetic and hyperkinetic movement,” wrote Markey and colleagues in the journal Otolaryngology. Hypokinetic movement involves less movement, while hyperkinetic movement involves more movement.

“Clinically, this manifests as contraction of the orbicularis oris muscle simultaneous with eye closure or blinking and/or contraction of the orbicularis oculi during speaking or chewing,” explains Rubin in the Handbook of Clinical Neurology. Orbicularis oris muscles are the group of muscles in the lips that encircles the mouth.

Clinical Features of Nonflaccid Facial Palsy

“Patients affected by NFFP often have a narrowed palpebral fissure, prominent and misoriented nasolabial fold, neck and face tightness, and mentalis dimpling,” writes Miller and colleagues in the journal Facial Plastic Surgery & Aesthetic Medicine. “These muscles can make a smile asymmetry.”

A narrowed palpebral fissure is a narrowing of the eye opening between the eyelids. Mentalis are the chin muscles.

Lyme Disease as a Cause of NFFP

Bell’s palsy can lead to NFFP in 15–30% of patients, writes Miller. “Other common causes of NFFP include Ramsay Hunt syndrome, acoustic neuroma resection, Lyme disease, trauma, autoimmune disease.”

Patients can suffer from NFFP with significant functional, aesthetic, psychological, and social impairments,” writes Miller. To view photos of patients with both flaccid and nonflaccid facial palsy, visit “The spectrum of facial palsy: The MEEI facial palsy photo and video standard set.”

Treatment Options for Nonflaccid Facial Palsy

There is a wide range of treatments for NFFP including:

• Physical therapy
• Muscle relaxants
• Facial massage
• Acupuncture
• Myectomy
• Neurectomy
• Botox

Frequently Asked Questions

What is nonflaccid facial palsy?

Nonflaccid facial palsy (NFFP) is a spectrum of involuntary facial movements that can occur after facial nerve injury. It includes both hypokinetic movement (decreased movement) and hyperkinetic movement (excessive involuntary movement), often causing the eye to close when trying to smile or facial muscles to contract while chewing.

What percentage of Bell’s palsy cases develop nonflaccid facial palsy?

Studies show that 15-30% of Bell’s palsy patients develop nonflaccid facial palsy. This complication can cause significant functional, aesthetic, psychological, and social impairments.

Can Lyme disease cause nonflaccid facial palsy?

Yes. Lyme disease is listed among the common causes of NFFP, along with Ramsay Hunt syndrome, acoustic neuroma resection, trauma, and autoimmune disease. When Bell’s palsy is caused by Lyme disease, NFFP can develop as a complication.

What are the visible signs of nonflaccid facial palsy?

Visible signs include narrowed eye opening (palpebral fissure), prominent and misoriented nasolabial fold, neck and face tightness, chin muscle dimpling (mentalis dimpling), and smile asymmetry. These features distinguish NFFP from standard flaccid Bell’s palsy.

What treatments are available for nonflaccid facial palsy?

Treatment options include physical therapy, muscle relaxants, facial massage, acupuncture, myectomy (muscle removal), neurectomy (nerve sectioning), and Botox injections. The choice of treatment depends on the severity and specific manifestations of the condition.

Clinical Takeaway

Nonflaccid facial palsy is not a rare complication—it develops in 15-30% of Bell’s palsy cases. When Lyme disease is the underlying cause of facial palsy, patients face the same risk of developing these involuntary facial movements. The functional and social impact can be profound: difficulty eating, drinking, and smiling normally, combined with visible facial asymmetry that affects social interactions and self-image.

I have seen firsthand in my practice how NFFP affects patients with Lyme disease. The aesthetic, psychological, and social impairments are significant and warrant specialized treatment beyond standard antibiotics. Patients need access to the full range of therapeutic options—from physical therapy and Botox to surgical interventions when conservative measures fail. Early recognition of Lyme disease and appropriate antibiotic treatment may help prevent some cases of NFFP, though this complication can still develop even with proper treatment.