Facial paralysis: A focus on synkinesis and treatment options

It may not be a term you're familiar with, but "synkinesis" is a common type of facial paralysis. This issue is characterized by an imbalance in facial function following a facial nerve event or injury that results in a nerve no longer working properly or that regenerates in an improper manner. Synkinesis can also cause twitching and spasticity, which can be very uncomfortable and sometimes painful for patients experiencing it.

Synkinesis was once thought to be untreatable, but recent advancements within the field of plastic surgery have proven otherwise. Using a variety of innovative techniques, surgeons are working to provide relief for patients with synkinesis and encourage more balanced facial movement. As this subspecialty is still evolving, there is no textbook technique to treat synkinesis, and there are few surgeons who specialize in this area of plastic surgery.

To gather more insight on the topic of synkinesis and the treatment options available, we reached out to a leading expert in the field.

ASPS Member Surgeon Andre Panossian, MD, is a plastic surgeon specializing in the treatment of synkinesis and facial paralysis as a whole. He took time to speak with us about this condition, its prognosis and treatment options available for patients.

A brief examination of synkinesis

Synkinesis is a type of facial paralysis that happens after a facial nerve event or injury, such as Bell's palsy or a traumatic accident. It often appears following damage to a nerve that causes it to no longer work properly.

"This condition is the miswiring or aberrant wiring that occurs with regeneration of the facial nerve," said Dr. Panossian. "That means that there are muscle groups that are activating involuntarily with other muscle groups, where they used to be separate functions. For example, if you go to pucker your lips, your eyelid closes on one side."

Patients with synkinesis can experience abnormal nerve regeneration, which involves incorrect wiring that connects the wrong muscle to the wrong nerve.

"There are theories as to why this happens," said Dr. Panossian. "The running theory is that the facial nerve is unlike any nerve in the body – there are multiple muscle groups controlled and multiple redundancies throughout. As a facial nerve moves through the face, it keeps dividing into more and more branches until it reaches the musculature of the face. As it does, you're getting progressive redundancy through the branches that occur. During natural formation, these are separate functions. With nerve regeneration, it can somehow veer along redundant pathways into other muscle groups that weren't the intended target."

In addition to partial paralysis of the face, synkinesis can also cause unwanted muscle twitching or spasticity. This can be both uncomfortable and especially frustrating for patients to experience in combination with the imbalance of their facial movements.

Treatment options for synkinesis and facial paralysis

Currently, there are two common treatment options – selective neurolysis and symmetry procedures. These procedures vary from surgeon to surgeon. However, they are both performed with the same goal in mind – to stop twitching or spasticity in the face. One commonality in the procedures is that before the treatment is performed, patients must first be closely examined to determine which stage of synkinesis they're in – mild, moderate or severe.

Oftentimes, the first step following this determination is to attempt treatment with Botox.

"These are very unique locations for injection," said Dr. Panossian. "We always start off with a very specialized version of Botox application. We'll place it, for example, along the margins of the eyelids. You can also use it on the opposite side to create paralysis in order to create more facial symmetry. Usually, when we use Botox in that situation, we're Botoxing the normal side to create symmetry."

The effects of Botox are temporary and can be reversed. If patients like how Botox performs, surgeons can then use the results to create a proper, long-term surgical plan to mimic them.

Selective neurolysis

This procedure involves a 'trimming' of abnormal or redundant nerve branches, but this surgery can be intensive and ineffective for many surgeons and patients.

"We're trying to stimulate those branches during surgery and cut out as many as possible," said Dr. Panossian. "However, this is inefficient. You're never going to tackle hundreds and hundreds of branches that feed into muscles. In general, I'll take out some of the larger branches that are causing the problem in combination with a muscle-focused approach. It's not enough to do a nerve procedure alone. This will cause an interruption of stimulation and can help eliminate the twitching. I'll leave the primary pathway to allow proper movement."

This type of procedure can also be risky to perform as well, with some patients experiencing further facial paralysis afterward.

"There's a fine line between controlling the nerves and musculature and paralyzing them, so you have to be very careful," said Dr. Panossian.

Symmetry procedures

This treatment involves creating symmetry in the face, whether through balancing out the facial paralysis or encouraging movement in the areas of the face experiencing the paralysis.

"As part of the surgery, I'll often recommend these symmetry procedures," said Dr. Panossian. "These are static procedures that serve to anchor anatomic facial features in place and destroy function in facial downstream muscles that don't need to be active. For example, lifting your forehead up doesn't have a great level of importance in daily life. In general, we combine destruction of the nerves that lead into that muscle in both sides of the forehead with a brow lift, and that will usually do the trick for a lot of people."

This helps the face appear more balanced overall.

Further treatment options

It's important to remember that final results may not be seen immediately after the procedure, and further treatments may be needed.

"We always have to wait a period of time following a procedure so that things can heal enough to get a good sense of how we did," said Dr. Panossian. "It's not always clear cut what the therapy should be until you heal up. Sometimes, the synkinesis is so prevalent that it comes back. With some patients, we have to see how much recovery we can accomplish before we decide what to do next, whether Botox, therapy or more surgery. If I see some deficiency that therapy can be valuable for, I will initiate that right away. However, it's seldom needed."

Using selective neurolysis, symmetry procedures and other state-of-the-art techniques, plastic surgeons are working to minimize the spasticity and twitching associated with synkinesis and balance out asymmetrical facial functions in patients. As a relatively young subspecialty within plastic surgery, it's exciting to consider where facial paralysis treatment will take us in the future.

To find a qualified plastic surgeon for any cosmetic or reconstructive procedure, consult a member of the American Society of Plastic Surgeons. All ASPS members are board certified by the American Board of Plastic Surgery, have completed an accredited plastic surgery training program, practice in accredited facilities and follow strict standards of safety and ethics. Find an ASPS member in your area.