Muscle-Nerve-Nerve Grafting Improves Facial Reanimation in Rats Following Facial Nerve Injury

Nerve injury resulting in muscle paralysis from trauma or surgery is a major medical problem. Repair of such injuries with existing nerve grafting and reconstructive techniques often results in less than optimal outcomes. After previously demonstrating significant return of function using muscle-nerve-muscle (MNM) grafting in a rat facial nerve model, this study compares a variant of the technique, muscle-nerve-nerve (MNN) neurotization to MNM and interposition (IP) nerve grafting. Thirty male rats were randomized into four groups (1) control with no intervention, (2) repair with IP grafts, (3) MNM grafts and (4) MNN grafts. All groups had the buccal and marginal mandibular branches of the right facial nerve resected. Return of vibrissae movement, orientation, and snout symmetry was measured over 16 weeks. Functional recovery and muscle atrophy were assessed and quantified. All interventions resulted in significant improvement in vibrissae movement and orientation as compared to the control group (p < 0.05). The MNM and MNN groups had significantly less time to forward vibrissae movement as compared to controls (p < 0.05), and a large number of animals in the MNN group had coordinated vibrissae movement at 16 weeks. MNN and IP grafts retained significantly more muscle mass as compared to control (p < 0.05). Thus, MNN grafting is a promising adjuvant or alternative technique for reanimation for patients with unilateral peripheral nerve injury who are not candidates for primary neurorrhaphy.

Facial synkinesis: A distressing sequela of facial palsy

Introduction Synkinesis refers to abnormal involuntary facial movements that accompany volitional facial movements. Despite a 55% incidence of synkinesis reported in patients with enduring facial paralysis, there is still a lack of complete understanding of this debilitating condition, leading to functional limitations and decreased quality of life. 1 This article reviews the diagnostic assessment, etiology, pathophysiology, rehabilitation, and nonsurgical and surgical treatments for facial synkinesis. Methods A PubMed and Cochrane search was done with no date restrictions for English-language literature on facial synkinesis. The search terms used were “facial,” “synkinesis,” “palsy,” and various combinations of the terms. Results The resultant inability to control the full extent of one’s facial movements has functional and psychosocial consequences and may result in social withdrawal with a significant decrease in quality of life. An understanding of facial mimetic musculature is imperative in guiding appropriate intervention. While chemodenervation with botulinum toxin and neurorehabilitation have continued to be the primary treatment strategy for facial synkinesis, novel techniques such as selective myectomy, selective neurolysis, free-functioning muscle transfer, and nerve grafting techniques are becoming increasingly utilized in treatment regimens. Facial rehabilitation, including neuromuscular retraining, soft tissue massage, and relaxation therapy in addition to chemodenervation with botulinum toxin, remains the cornerstone of treatment. In cases of severe, intractable synkinesis and non-flaccid facial paralysis, surgical interventions, including selective neurectomy, selective myectomy, nerve grafting, or free muscle transfer, may play a more significant role in alleviating symptoms. Discussion A multidisciplinary approach involving therapists, clinicians, and surgeons is necessary to develop a comprehensive treatment regimen that will result in optimal outcomes. Ultimately, therapy should be tailored to the severity and pattern of synkinesis, and each patient approached on a case-by-case basis. A multidisciplinary approach involving therapists, clinicians, and surgeons is necessary to develop a comprehensive treatment regimen that will result in optimal outcomes.

Traumatic Brachial Plexus Injury in Indonesia: An Experience from a Developing Country

Background Brachial plexus injuries (BPI) cause severe physical disability and major psycho-socioeconomic burden. Although various countries have reported BPI incidence, the data from Indonesia as the fourth most populated country in the world remains unknown. We aim to assess the distribution of traumatic BPI, patients' characteristics, and treatment modalities in Indonesia. Methods A retrospective investigation was performed comprising 491 BPI patients at a tertiary referral hospital in Indonesia from January 2003 to October 2019. Demographic and outcomes data were retrieved from medical records. Results The average BPI patients' age was 27.3 ± 11.6 years old, with a male/female ratio of 4.6:1. Motorcycle accidents caused the majority (76.1%) of all BPI cases. Concomitant injuries were present in 62.3% of patients, dominated by fractures (57.1%) and brain injuries (25.4%). BPI lesion type was classified into complete (C5-T1, observed in 70% patients), upper (C5-C6, in 15% patients), extended upper (C5-C7, in 14% patients), and lower type (C8-T1, in 1% patients). The average time to surgery was 16.8 months (range 1–120 months), with the majority (76.6%) of the patients was operated on six months after the trauma. Free functional muscle transfer (FFMT) was the most common procedure performed (37%). We also analyzed the functional outcomes (active range of motion (AROM) and muscle power), DASH (Disabilities of the Arm, Shoulder, and Hand) score, and VAS (Visual Analogue Scale) across four most frequent procedures involving nerve reconstruction (FFMT, nerve transfer, external neurolysis, and nerve grafting). We found that FFMT was significantly better than nerve transfer in terms of DASH score and VAS (p = 0.000 and p = 0.016, respectively) in complete BPI (C5-T1). Moreover, we also found that nerve grafting resulted in a significantly better shoulder abduction AROM than nerve transfer and external neurolysis in extended upper BPI (C5-C7) (p = 0.033 and p = 0.033, respectively). Interestingly, no significant differences were observed in other measurements. Conclusion This study provides an overview of traumatic BPI patients in a single tertiary trauma center in Indonesia, expressing the profile of their characteristics and functional outcomes after surgical procedures.

Nerve Transfer Is Superior to Nerve Grafting for Suprascapular Nerve Reconstruction in Obstetrical Brachial Plexus Birth Injury: A Meta-Analysis

Background Restoration of shoulder function in obstetrical brachial plexus injury is paramount. There remains debate as to the optimal method of upper trunk reconstruction. The purpose of this study was to test the hypothesis that spinal accessory nerve to suprascapular nerve transfer leads to improved shoulder external rotation relative to sural nerve grafting. Methods A systematic review of Medline, EMBASE, EBSCO CINAHL, SCOPUS, Cochrane Library, and TRIP Pro from inception was conducted. Our primary outcome was shoulder external rotation. Results Four studies were included. Nerve transfer was associated with greater shoulder external rotation relative to nerve grafting (mean difference: 0.82 AMS 95% confidence interval [CI]: 0.27-1.36, P < .005). Patients undergoing nerve grafting were more likely to undergo a secondary shoulder stabilizing procedure (odds ratio [OR]: 1.27, 95% CI: 0.8376-1.9268). Conclusion In obstetrical brachial plexus injury, nerve transfer is associated with improved shoulder external rotation and a lower rate of secondary shoulder surgery. Level of Evidence Level III; Therapeutic

Nerve grafts and transfers

Following Cruickshank’s (1795) ingenious (and at first disbelieved) demonstration of the regenerative capacity of mammalian nerves, the eighteenth and nineteenth centuries saw a pan-European enthusiasm to redress the nihilism surrounding nerve injury. The first recorded experimental nerve grafts were performed by Philipeaux and Vulpian who attempted both nerve autografting as well as allografting in dogs. At that time, and for many years, allografts were thought to behave similarly to autografts, a belief that persisted well into the twentieth century in some clinics and laboratories. These early attempts at nerve grafting yielded poor results and most surgeons aimed for primary nerve repair despite nerve gaps. Other techniques to allow direct repair involved alteration of position, transposition of the nerve, and even sometimes bone shortening. Although primary repair was frequently possible, after these measures the repair was under tension and mechanical failure was common. Spurling (1945), Whitcomb (1946), and Woodall (1956) showed failure rates of 4%, 7.5%, and 22.4% respectively. Some recovery of function following nerve grafting was documented by Sanders (1942), Seddon (1954), and Brooks (1955). Millesi subsequently published his results for nerve grafting for injuries to the upper limb in 1984. These papers demonstrated more significant recovery of function and highlighted the detriment of delay in treatment to final outcome. Microsurgical advances were central to Millesi’s results, and he emphasized atraumatic dissection and the deleterious effect of tension at the repair site resulting in fibrosis preventing axonal regrowth. Nerve autograft is now the standard for orthotopic nerve reconstruction when primary repair cannot be achieved.