Physiotherapy and Surgery for Facial Nerve Paralysis

Imagine losing your ability to convey tone and emotion through facial expressions. The loss of facial function due to facial nerve paralysis can significantly affect confidence and emotional wellbeing. Facial nerve paralysis is a result of damage or injury to the seventh cranial nerve, a.k.a. the facial nerve. The facial nerve controls facial expression, salivary function, taste in parts of the tongue, and has a small role in ear function (1).

Treatment Options

Understanding the cause (Fig. 1) and extent (complete or incomplete) of facial nerve paralysis is important in guiding treatment and in setting patient expectations for recovery (‘prognosis’) (1). Treatment options include both physical rehabilitation and surgical interventions.

Fig 1. The four overarching categories of potential causes for facial paralysis organized by incidence (1).

Physiotherapy for Facial Nerve Paralysis

Physiotherapy can be an essential part of your journey to recovery after facial nerve paralysis and should be offered regardless of how transient or chronic the paralysis is (2). When to see a physiotherapist, and what that physiotherapy care might look like will depend on the cause and prognosis of the nerve paralysis, as well as any follow-on issues (‘sequelae’) that the paralysis may have caused (3).

The potential consequences of facial nerve paralysis include little-known neuromuscular conditions such as synkinesis, asymmetry, hyperkinesis, muscle atrophy, and contracture.  The most common of these outcomes is synkinesis, a condition where the deliberate contraction of muscles in one area of the face causes an involuntary contraction in another. For example, oral-ocular synkinesis is the involuntary movement of the mouth during voluntary eye movement (such as blinking or eyebrow raising). Synkinesis is thought to arise from poor nerve regeneration during the healing process of the facial nerve. Research suggests that patients with incomplete recovery after facial nerve paralysis can benefit from a physical rehabilitation program including neuromuscular re-education, exercise therapy, and biofeedback (4,5).

Physiotherapy treatment may include:

• Soft tissue massage and stretching to address adaptive shortening/tension of impacted muscles.
• Development of an individualized exercise program to address facial asymmetries. This may involve biofeedback and/or mirror therapy to work on muscle strengthening and importantly, muscle patterning, control, and coordination.
• Education regarding facial muscles and their function, expected progression, and timeline of recovery.

Surgical Options for Facial Nerve Paralysis

Along with conservative management in the form of physical rehabilitation, there are many potential surgical interventions that can help. Two common surgeries include neural repair where a damaged nerve is sutured back together, and neural decompression where structures compressing the nerve are removed (6).

Patients where neural repair or decompression are not possible or unsuccessful may be referred to a plastic surgeon like Dr. Baltzer at the Toronto Western Hospital to undergo a more involved surgical procedure known as “facial reanimation”. Dr. Baltzer is one of a handful of surgeons in Canada who perform facial reanimation surgery in adults (7).

Unlike neural repair or decompression which attempt to recover the function of the existing damaged nerve, the goal of facial reanimation surgery is to provide an entirely new neural input to the facial muscles that have been left dysfunctional by nerve damage. This can be done in one of three ways: nerve graft, nerve transfer, or a combination of both (Fig. 2). A nerve graft involves transplanting a piece of a healthy nerve from another part of the body into the affected area where it will then have to regenerate. A nerve transfer involves borrowing a nerve branch from a nearby area and attaching it to the affected muscle. Picture replacing a wire (nerve graft) versus plugging a wire into a new plug (nerve transfer) (7). Additionally, in some cases nerve grafts and/or transfers occur alongside muscle transplants. This would be recommended in cases where the facial muscle has been significantly damaged or atrophied as a result of the initial nerve damage. In fact, facial reanimation surgery ideally takes place within one year of facial paralysis to avoid more significant muscle atrophy that can occur (6).

Fig 2. Combination of nerve graft and transfer using a nerve from the leg to supply input to the paralyzed side of the face. Modified from Ref 6.

Post-surgical Physiotherapy

Physical rehabilitation plays an important role in post-surgical recovery as well. Since 50% of those treated surgically will develop mild or moderate synkinesia (8), it is not surprising that post-surgical physiotherapy treatment can look very similar to non-surgical physiotherapy care. In addition to the physiotherapy treatments listed above, post-surgical physiotherapy for facial nerve paralysis may also employ manual lymphatic drainage techniques to help manage surgery-related swelling (9).

The timeline for initiating post-surgical physiotherapy will largely depend on need as assessed by the surgeon. With that said, there is evidence to support the efficacy of post-surgical physiotherapy throughout the recovery period, as early as 5 weeks post-surgery (9), and for chronic cases as late as 13 years  following nerve paralysis (10).  Regardless of the timeframe, the treating physiotherapist will establish a treatment plan based on four categories that pertain to typical signs and symptoms: initiation, facilitation, movement control, and relaxation (see Table 1) (3).

Table 1. Symptom-based categories which guide physiotherapy treatment approach. (Modified from Ref 3).

Facial paralysis is a challenging and complex condition, but significant recovery can be possible. Optimal results are typically realized through a multidisciplinary approach and collaborative treatment plan.

References:

1. Mavrikakis I., Facial Nerve Palsy: Anatomy, Etiology, Evaluation, and Management. Orbit. 2008; 27, 466-474.
2. Karp E., Waselchuk E., et al. Facial Rehabilitation as Noninvasive treatment for Chronic Facil Nerve Paralysis. Otology & Neurology. 2018; 40, 241-245.
3. Brach J., VanSwearingen J., Physical Therapy for Facial Paralysis: A Tailored Treatment Approach. Physical Therapy. 1999; 79(4), 397-404
4. Pourmomeny A., Asadi S., Managment of Synkinesis and Asymmetry in Facial Nerve Palsy: A Review Article. Iranian Journal of Otorhinolaryngology. 2014; 26(4) 251-256.
5. Liapids J., et al. Too much or too little? A systematic review of post paretic synkinesis treatment. Journal of plastic, Reconstructive & Aesthetic Surgery 2020; 73, 443-452
6. Mehta R., Surgical Treatment of Facial Paralysis. Clin Exp Otorhinolaryngol. 2009 Mar; 2(1): 1–5.
7. Not Just reason, but ability to smile again: https://www.uhn.ca/corporate/News/Pages/Not_just_reason_but_ability_to_smile_again.aspx
8. Placheta E., et al., Facial Synkinesia before and after Surgical Reanimation of the Paralyzed Face. Plastic and Reconstructive Surgery. 2014; 133(6).
9. Wilsion C., Ronan S., Rehabilitation Post facial Reanimation Surgery After Removal of Acoustic Meuroma: A Case Study. JNPT. 2010; 34: 41-49.
10. Cronin G., Leif Steenerson R., The effectiveness of neuromuscular facial retraining combined with electromyography in facial paralysis rehabilitation. Otolayngology-Head and Neck Surgery. 2003; 128(4), 534-538