Masseteric nerve supercharge bypass in primary reconstruction of facial nerve

Reverse End-to-Side Transfer to Ulnar Motor Nerve: Evidence From Preclinical and Clinical Studies

The disappointing outcomes of conventional nerve repair or grafting procedures for proximal ulnar nerve injuries have led the scientific community to search for better alternatives. The pronator quadratus branch of the anterior interosseous nerve has been transferred to the distal ulnar motor branch in a reverse end-to-side fashion with encouraging results. This transfer is now becoming commonly used as an adjunct to cubital tunnel decompression in patients with compressive ulnar neuropathy, underscoring the need for this knowledge transfer to the neurosurgical community. However, the mechanism of recovery after these transfers is not understood completely. We have reviewed the existing preclinical and clinical literature relevant to this transfer to summarize the current level of understanding of the underlying mechanisms, define the indications for performing this transfer in the clinic, and identify the complications and best practices with respect to the operative technique. We have also attempted to identify the major deficiencies in our current level of understanding of the recovery process to propose directions for future research.

The evaluation of the effect of free gracilis muscle transfer on cheek tone and oral competence in long-standing facial paralysis of patients by using Blasco index

PURPOSE

Smile and eyelid reanimation are generally emphasized in facial reanimation, but the loss of cheek tone provided by the buccinator muscle is not adequately addressed. The use of free gracilis muscle flap for facial reanimation has become widespread since it was used in head and neck reconstruction by Harii et al. The effect of free gracilis muscle transfer on drooling is not clearly defined in the literature. In our study, we aimed to evaluate the effect of free gracilis muscle transfer on drooling in patients with facial paralysis (FP) by using Blasco index. Smile function was overemphasized in the literature, but drooling was not evaluated. What happens to drooling after free functional muscle transfer was not clear, so this study was designed to evaluate improvement in drooling.

PATIENTS AND METHODS

Drooling and smile were evaluated in 11 patients (4 male, 7 female) who underwent facial reanimation with a free functional gracilis muscle transfer (FFGMT), in long-standing FP. The mean age was 39.9 years (range 22-56 years). Etiology was idiopathic in two patients, trauma in five patients, and intracranial tumor in four patients. Photographs and video recordings were taken preoperatively and at the first year postoperatively. The muscle was stitched to the upper lip, corner of the mouth, lower lip and the preauricular region. Masseteric nerve was preferred as donor nerve. Smile restoration was evaluated according to the five-stage classification defined by Terzis and Noah.

RESULTS

Flap dimensions differed from 12 cm× 5 cm to 15 cm× 6 cm. Oral intake was stopped for 5 days, and speaking was restricted postoperatively. Patients exercised for about 1 h starting from the postoperative third month. Patients were followed up for an average of 26.5 (14-48) months postoperatively. Postop courses were uneventful, and we did not observe any complications in these patients. Preoperative Blasco index score was 3 in 6 patients, 2 in 5 patients and the mean scores were 2.54 ± 0.52. Patients were followed for 1 year. No drooling was observed in the postoperative first year. The Blasco index score was 0 for all patients. The decrease in postoperative scores was found to be statistically significant (p < .01). Smile restoration was evaluated according to the five-stage classification defined by Terzis and Noah for facial reanimation after muscle transfer. Excellent results (grade 5) were obtained in 6 patients, good results (grade 4) in 4 patients and moderate results (grade 3) in 1 patient.

CONCLUSION

Free functional gracilis muscle transfer improves chewing functions and prevents drooling. This case series reveals that FFGMT can be a good option to enable cheek tone in long-standing FP of patients.

Mechanisms and outcomes of the supercharged end-to-side nerve transfer: a review of preclinical and clinical studies

Proximal peripheral nerve injuries often result in poor functional outcomes, chiefly because of the long time period between injury and the reinnervation of distal targets, which leads to muscle and Schwann cell atrophy. The supercharged end-to-side (SETS) nerve transfer is a recent technical innovation that introduces donor axons distally into the side of an injured nerve to rapidly innervate and support end organs while allowing for additional reinnervation after a proximal repair at the injury site. However, the mechanisms by which donor axons grow within the recipient nerve, contribute to muscle function, and impact the regeneration of native recipient axons are poorly understood. This uncertainty has slowed the transfer's clinical adoption. The primary objective of this article is to comprehensively review the mechanisms underpinning axonal regeneration and functional recovery after a SETS nerve transfer. A secondary objective is to report current clinical applications in the upper limb and their functional outcomes. The authors also propose directions for future research with the aim of maximizing the clinical utility of the SETS transfer for peripheral nerve surgeons and their patients.