Using the “Sugarcane Chewing” Concept as the Directionality of Motor Neurotizer Selection for Facial Paralysis Reconstruction: Chang Gung Experiences

Dual versus Single Innervation of Gracilis Free Functional Muscle Transfer in Facial Paralysis: Long-Term Resting and Dynamic Outcomes

BACKGROUND

The purpose of this study was to compare long-term tone and excursion in single- versus dual-innervated free functional muscle transfer (FFMT) in patients with longstanding facial paralysis.

METHODS

Patients with longstanding facial palsy treated with an FFMT innervated either by a nerve-to-masseter graft (single-innervation group) or nerve-to-masseter and cross-facial-nerve grafts (dual-innervation group) were included. One-year minimum follow-up was required. Outcome measures, based on standardized photographs, included excursion, smile angle, teeth exposure, commissure height deviation, and upper lip height deviation in repose and in closed and open-teeth smile preoperatively and at 3 months, 1 year, and 3 years postoperatively. Emotrics software and ImageJ software were used to take measurements. Between-group and within-group longitudinal comparisons were analyzed.

RESULTS

At 3 years (single, n = 24; dual, n = 13), significance was found between groups in commissure position (single, 26.42 mm versus dual, 31.51 mm; P < 0.0001) and excursion with open-mouth smile (single, 31.32 mm versus dual, 26.59 mm; P < 0.001). Single-innervation FFMT within-group analysis lacked significant improvement in commissure height deviation and upper lip height deviation at 3 years in repose, whereas the dual-innervation group revealed significant improvements (3.67 mm [ P < 0.001], 3.17 mm [ P < 0.001], respectively). Teeth exposure revealed an increase in the dual-innervation group (single, 35.753 mm 2 versus dual, 64.177 mm 2 ), but significance was not observed.

CONCLUSION

Dual-innervated FFMT revealed improvements in resting tone and teeth exposure with minimal decrease in smile excursion compared with single-innervated FFMT.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Dynamic Repair Surgery for Late-Stage Facial Paralysis: Advances in Restoring Movement and Function

Purpose: Facial paralysis results from congenital or acquired facial nerve damage, leading to significant cosmetic and functional deficits. Surgical resection of parotid and midface tumors can cause facial paralysis, necessitating effective treatment strategies. This review addresses the challenge of restoring movement and function in late-stage facial paralysis, focusing on dynamic repair techniques involving nerve and muscle transplantation. Methods: The review encompasses studies on dynamic repair surgery for late facial paralysis, including techniques such as local muscle flap with pedicle transfer, vascularized nerve flap with pedicle transfer, and multiple muscle flap procedures. A systematic literature search was conducted using PubMed, Web of Science, and Google Scholar, covering studies from 2000 to 2024. Keywords included "dynamic repair", "late-stage facial paralysis", "nerve and muscle transplantation", "muscle flap", and "tendon transposition". Included were clinical studies, systematic reviews, and meta-analyses reporting surgical outcomes. Exclusion criteria included studies with insufficient data and non-peer-reviewed articles. Results: Dynamic repair techniques involving nerve and muscle transplantation are essential for treating late-stage facial paralysis. Each surgical method has strengths and limitations. The masseter muscle flap demonstrates high success rates, although it can cause horizontal tension and jaw contour issues. The temporalis muscle flap is effective for smile restoration but may lead to temporal concavity. The gracilis muscle flap is widely used, especially with dual nerve innervation, showing high success in spontaneous smiles but requiring a longer recovery period. The latissimus dorsi flap is effective but can cause edema and shoulder issues. The serratus anterior free flap offers flexibility with precise vector positioning but may not achieve adequate lip elevation and can cause cheek swelling. Combined multi-flap surgeries provide more natural facial expressions but increase surgical complexity and require advanced microsurgical skills. Conclusions: Dual nerve innervation shows promise for restoring spontaneous smiles. One-stage surgery offers faster recovery and reduced financial burden. Comprehensive patient evaluation is crucial to select the most suitable surgical method. Dynamic repair techniques involving nerve and muscle transplantation provide effective solutions for restoring function and aesthetics in late-stage facial paralysis. Future research should focus on long-term outcomes, patient satisfaction, and standardizing surgical protocols to optimize treatment strategies.

Age-related outcomes of facial reanimation surgery using gracilis free functional muscle transfer innervated by the masseteric nerve: A retrospective cohort study

BACKGROUND

The free functional muscle gracilis transfer is an established approach in facial reanimation surgery; however, the significance of its neurotization and the patient's age is still inconclusive. Several donor nerves are available for facial reanimation using the free functional gracilis muscle transfer.

OBJECTIVE

This retrospective cohort study investigates whether the masseteric nerve is an equally reliable donor nerve in both older and younger patients.

METHODS

We included 46 patients (13-71 years, male and female) who underwent nerve-to-masseter (NTM)-driven free functional muscle transfer (FFMT) between January 2008 and December 2019. Patients were distributed into three cohorts according to their age at surgery. We assessed the facial symmetry before and after surgery using the pupillo-modiolar angle. Commissure height and excursion deviation were measured with the Emotrics software. Patient-reported outcome measurements were taken using the Facial Clinimetric Examination (FaCE) scale.

RESULTS

All patients had successful flap innervation, except for one patient in the middle-aged cohort (31-51 years). The postoperative facial symmetry at rest, smiling, and laughing was analyzed with the pupillo-modiolar angle and the Emotrics software and showed similar results between all cohorts. The FaCE scale showed similar scores for the middle-aged (31-51 years) cohort and the senior cohort (52-71 years). The social function score in the senior cohort was higher than in the middle-aged cohort, without statistical significance. One patient in the middle-aged (31-51 years) cohort and the senior cohort (52-71 years), respectively, underwent emergency revision due to impaired flap perfusion and could be salvaged.

CONCLUSIONS

NTM-driven FFMT for facial reanimation is a safe and reliable procedure across all age groups of patients.

Phrenic Nerve as an Alternative Donor for Nerve Transfer to Restore Shoulder Abduction in Severe Multiple Root Injuries of the Adult Brachial Plexus

PURPOSE

Nerve transfer is the gold standard to restore shoulder abduction in acute brachial plexus injuries. The aim of this study was to compare the phrenic nerve (Ph) to the spinal accessory nerve (XI) as the donor nerve for this purpose.

METHODS

A retrospective chart review was performed on 136 patients with acute brachial plexus injuries who received a nerve transfer of the shoulder with either the Ph (94 patients) or XI (42 patients). Each group was divided into 3 subgroups based on the recipient nerve. The maximum degree of shoulder abduction was recorded after 2 years of postoperative follow-up. A generalized estimating equation model was performed to examine the variables affecting shoulder abduction over time.

RESULTS

The maximum degrees of shoulder abduction achieved were 61.9° ± 38.7° in patients with Ph and 51.1° ± 37.3° in patients with XI. More than M3 shoulder abduction was achieved by 67% of patients with Ph versus 59% of patients with XI. The regression analysis showed that the age at the time of surgery correlated more with the functional outcome over time than the choice of donor nerve.

CONCLUSIONS

In multiple root brachial plexus injuries, the Ph exhibited similar outcomes to the XI for shoulder abduction. Our routine exploration of the supraclavicular plexus exposes the Ph conveniently for nerve transfer. The phrenic nerve should be considered as an alternative when the XI is not available or is reserved for secondary reconstruction.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Comparison of static and dynamic symmetry between masseter-innervated and dual-innervated free multivector serratus anterior muscle transfer for complete facial paralysis

PURPOSE

In this study, facial symmetry was compared between the masseter-innervated and dual-innervated free multivector serratus anterior muscle transfer (FMSAMT) methods.

METHODS

Eighteen patients with unilateral complete facial paralysis underwent facial reanimation surgery between April 2006 and July 2019. The masseter-innervated FMSAMT group (Group M, n = 8) underwent end-to-end coaptation with the ipsilateral masseter nerve in one stage. The dual-innervated FMSAMT group (Group D, n = 10) underwent end-to-end coaptation with the masseter nerve and end-to-side coaptation with the contralateral facial nerve via cross-face nerve graft. They were further divided into the one-stage (Group D1, n = 5) and two-stage (Group D2, n = 5) subgroups. The durations of periods until the first visible muscle contraction with clenching, first spontaneous smile, and the completion of resting tone were evaluated. The possibility of a spontaneous smile and symmetry of the midline and horizontal deviation at rest and during voluntary smiling were compared between each group.

RESULTS

Groups M and D differed significantly in the possibility of a spontaneous smile and improvement rate of midline deviation and horizontal deviation at rest (p < 0.001, p < 0.001, and p = 0.001, respectively) but not in the improvement rate of midline and horizontal deviation during voluntary smiling. The duration of the period until the completion of resting tone was significantly shorter in Group D1 than in Group D2 (p = 0.048); however, the possibility of a spontaneous smile and the improvement rate of midline and horizontal deviation were not significantly different.

CONCLUSIONS

Dual-innervated FMSAMT was effective in guaranteeing a symmetrical resting tone, voluntary smiling, and reproducing a spontaneous smile.

Donor nerve selection in free gracilis muscle transfer for facial reanimation. A systematic review and meta-analysis of clinical outcomes

BACKGROUND

One of the critical factors in facial reanimation is selecting the donor nerve. The most favored neurotizers are the contralateral facial nerve with a cross-face nerve graft (CFNG) and motor nerve to the masseter (MNM). A relatively new dual innervation (DI) method has shown successful results. This study aimed to compare the clinical outcomes of different neurotization strategies for free gracilis muscle transfer (FGMT).

METHODS

The Scopus and WoS databases were queried with 21 keywords. Three-stage article selection was performed for the systematic review. Articles presenting quantitative data for commissure excursion and facial symmetry were included in meta-analysis, using random-effects model. ROBINS-I tool and Newcastle-Ottawa scale were used to assess bias and study quality.

RESULTS

One hundred forty-seven articles containing FGMT were systematically reviewed. Most studies indicated CFNG as the first choice. MNM was primarily indicated in bilateral palsy and in elderly. Clinical outcomes of DI studies were promising. 13 studies including 435 observations (179 CFNG, 182 MNM, 74 DI) were eligible for meta-analysis. The mean change in commissure excursion was 7.15 mm (95% CI: 4.57-9.72) for CFNG, 8.46 mm (95% CI: 6.86-10.06) for MNM, and 5.18 mm (95% CI: 4.01-6.34) for DI. In pairwise comparisons, a significant difference was found between MNM and DI (p = 0.0011), despite the superior outcomes described in DI studies. No statistically significant difference was found in resting and smile symmetry (p = 0.625, p = 0.780).

CONCLUSIONS

CFNG is the most preferred neurotizer, and MNM is a reliable second option. Outcomes of DI studies are promising, but more comparison studies are needed to draw conclusions. Our meta-analysis was limited by incompatibility of the assessment scales. Consensus on a standardized assessment system would add value to future studies.

Dynamic reanimation of severe blepharoptosis using the neurotized omohyoid muscle graft

BACKGROUND

Attempts at dynamic reconstruction of the upper eyelid either by neurotization or direct muscle replacement have been scarce. Substitution of the levator palpebrae superioris muscle requires the use of extremely small and pliable structures. As a proof of concept/pilot study, we present a consecutive series of patients who underwent blepharoptosis correction using the neurotized omohyoid muscle graft.

METHODS

Retrospective analysis of patients receiving a neurotized omohyoid muscle graft for levator palpebralis substitution between January and December 2019.

RESULTS

Five patients were operated (2 male, 3 female); median age was 35.5 years. Median palpebral aperture was 0 mm and levator function was< 1 mm in all cases. Median denervation time for the levator muscle was 9 years. All surgeries were uneventful, and no postoperative complications were seen. Twelve months after the procedure, all patients presented with adequate palpebral aperture on activation of the spinal nerve. Median palpebral aperture was 6.5 mm Postoperative electromyography revealed muscle contraction when stimulation was applied to the spinal nerve.

CONCLUSION

This study introduces the concept of severe blepharoptosis correction using the omohyoid muscle. We believe that with time and further technical refinements it could become an invaluable tool in eyelid reconstruction surgery.

Functional Outcome Comparison of Free Gracilis Muscle Anchoring Methods in Patients with Facial Paralysis: Upper Lip Red Line Incision versus Facelift Incision Approach

BACKGROUND

 The greatest challenge of a free-muscle transfer in facial reanimation surgery is anchoring muscle to perioral soft tissue. An additional incision provides a better way to anchor the transferred muscle but leaves a visible scar. Herein, we compared the functional and aesthetic outcomes in a conventional facelift incision approach with and without the addition of a red line incision.

METHODS

 This study included patients experiencing unilateral facial paralysis who underwent free gracilis transfer between December 2016 and December 2018. Anchoring through facelift incision with extended neck incision was performed in the control group, while a red line incision was added in the red line group by avoiding extended neck incision. Oral commissure excursion, upper lip and commissure height differences, and symmetry were measured.

RESULTS

 A total of 24 patients met the criteria and were included in this study. Of these, 10 patients were assigned to the red line group and 14 to the control group. The red line and control groups demonstrated a similar symmetry index in both resting (0.96 ± 0.18 and 0.92 ± 0.10, respectively; p = 0.435) and smiling (0.94 ± 0.12 and 0.91 ± 0.10, respectively; p = 0.314). However, the upper lip height difference demonstrated greater postoperative improvement (resting: 2.12 ± 1.13 vs. 3.92 ± 1.41 mm, p = 0.002, and smiling: 1.68 ± 0.88 vs. 3.41 ± 1.69 mm, p = 0.004, respectively). A scar could be easily concealed on the mucocutaneous line of the lip.

CONCLUSION

 This novel method for muscle anchoring in facial reanimation surgery allows surgeons to approach perioral muscle more directly. This leads to improved surgical results by securely anchoring the transferred muscles using a fixation point that is more medially located than in other approaches. Our method is effective and offers an improved surgical outcome for the free functional gracilis muscle transfer.

Surgical Treatment for Postparalytic Facial Synkinesis - A 35 Year Experience

BACKGROUND

Surgical intervention with Combined myectomy & neurectomy followed by functioning free muscle transplantation (FFMT) has been proposed to effectively resolve the problem of postparalytic facial synkinesis (PPFS) since 1985, and continues to be our standard-of-care. We aim to provide evidence that this surgical strategy is effective for treatment of synkinesis and smile quality.

METHODS

103 patients with PPFS were investigated (1985-2020). They all underwent extensive removal of the synkinetic muscles and triggered facial nerve branches in the cheek, nose and neck regions, followed by gracilis FFMT for facial reanimation. Ninety-four patients with 50 Type II and 44 Type III PPFS patients, all of whom had at least one year of postoperative follow-up were included in the study. Patient's demographics, functional and aesthetic evaluations before and after surgery were collected.

RESULTS

In the yearly distribution of the facial paralysis reconstruction, the incidence of surgical intervention increased from 15% prior to 2012 up to 24% in the years after. Young adults (79%) and female patients (63%) were the dominant population. Results showed a significant improvement of the facial smile quality with more teeth visible while smiling, and a long-lasting decrease of facial synkinesis. Ninety six percent of patients did not require botulinum-A toxin injection after surgery. Revision surgery for secondary deformity was 53%.

CONCLUSION

Combined myectomy & neurectomy followed by FFMT for Type II and III synkinetic patients leads to promising and long-lasting results despite high revision rates. Refined techniques to decrease the revision rates are needed in the future.

Supercharged massetric-facial cross-graft for gracilis reinnervation in unilateral facial palsy treatment

BACKGROUND

The choice of neurotization source for gracilis neuromuscular transplant is a key point in the treatment of unilateral long-standing paralysis. To combine the advantages of different donor nerves and overcome their disadvantages, mixed neurotization sources have been described with encouraging results. The authors present a preliminary report of a novel technique, the "supercharged" cross-graft, a two-step technique consisting of a double powered cross nerve graft provided by a zygomatic branch of the healthy facial nerve and the masseter nerve of the healthy side.

PATIENTS AND METHODS

From January 2015 to December 2019 eight patients, aged between 19 and 61 years old (mean age at surgery 33.62) suffering unilateral established paralysis (congenital or acquired, >24 months) underwent gracilis reinnervation with the supercharged cross grafting technique. Subjects underwent a two-step surgical rehabilitation: in the first operation sural nerve was harvested and used as cross-graft cooptated by healthy side facial nerve branch and masseteric nerve. During second procedure gracilis neuromuscular transplant was performed reinnervarting the muscle with the cross-graft. Patients were evaluated using Emotrics software, which allowed for automated facial measurements on post-operative pictures taken at the last follow-up. The results of the different poses were compared to assess the contribution to smile excursion by the masseter and facial nerve, together and separately. Finally, we analyzed spontaneous smile to assess whether masseteric contribution is used in daily life.

RESULTS

No major or minor complications occurred. Follow-up time ranged from 12 to 41 months, with a mean of 22.75 months. A good commissure excursion (mean 33.84 mm) was obtained during smile with no teeth clenching (without masseter activation), as well as during teeth clenching without smiling (activation of gracilis only - mean 32.55). When smiling and biting simultaneously the excursion was greater than the single two components (mean 35.91). In spontaneous smile, commissure excursion was higher (mean 34.23) than that provided by only the facial nerve (smile only) in most patients.

CONCLUSIONS

This novel technique of mixed neurotization for gracilis transplant shows consistent results with powerful contraction and good smile coordination. It also allows us to extend the indications for mixed neurotization techniques.

A supportive donor nerve for long-term facial paralysis: Anatomical analysis of the posterior auricular nerve and micro-anatomical comparison with zygomatic nerve

BACKGROUND

The posterior auricular nerve (PAN) is an inspiring candidate for the additional axonal source in long-term facial paralysis to improve the functional results of the cross-facial nerve (FN) graft technique. However, no studies have analyzed the PAN's axonal load and its microscopic anatomy to assess its utilization in facial reanimation. The present study aims to examine the anatomical and microscopic features of the PAN to analyze its feasibility as a donor nerve.

METHODS

The bilateral facial side of 14 fresh frozen adult human cadavers was examined for the study. The PAN's anatomical course was recorded, and nerve specimens from the PAN and zygomatic nerve (ZN) were obtained to compare their microscopic anatomy and axon counts using a light microscope and transmission electron microscope.

RESULTS

The PAN's average branching distance and its course length were 5.8 ± 2.69 mm and 59.2 ± 5.85, respectively. The mean number of myelinated axons was 600.28 ± 69.97 in the PAN and 728.85 ± 166.31 in the ZN. This difference between the two nerves was statistically significant (p = 0.002). However, considering the gender variable, the mean axon counts of PAN and ZN were statistically similar for face sides and their average. Furthermore, the ultrastructural anatomy of both nerves was similar in electron microscopic evaluation.

CONCLUSIONS

The present study confirms that the PAN is a proper candidate to be a supportive donor nerve due to its isolated site, consistent anatomical course, convenient ultrastructural anatomy as well as axonal load.

Strategies to Improve Cross-Face Nerve Grafting in Facial Paralysis

Cross-face nerve grafting enables the reanimation of the contralateral hemiface in unilateral facial palsy and may recover a spontaneous smile. This chapter discusses various clinically applicable strategies to increase the chances for good functional outcomes by maintaining the viability of the neural pathway and target muscle, increasing the number of reinnervating nerve fibers and selecting functionally compatible donor nerve branches. Adopting those strategies may help to further improve patient outcomes in facial reanimation surgery.