Roles of preoperative and early postoperative electrodiagnosis in brachial plexus injury patients undergoing nerve transfer operations: retrospective feasibility study.

OBJECTIVE: The purpose of this retrospective observational study was to assess the feasibility of electrodiagnostic parameters, perioperatively, and to discover optimal values as prognostic factors for patients with brachial plexus injury undergoing nerve transfer operations. METHODS: We retrospectively reviewed the records of 11 patients who underwent nerve transfer surgery. The patients underwent perioperative electrodiagnosis (EDX) before and approximately 6 months after surgery. We evaluated the compound muscle action potential (CMAP) ratio, motor unit recruitment, and their interval changes. To evaluate motor strength, we used the Medical Research Council (MRC) grade, 6 and 12 months after surgery. We evaluated the relationships between improved CMAP ratio, and motor unit recruitment and MRC grade changes 6 and 12 months postoperatively. RESULTS: All parameters increased significantly after surgery. The CMAP ratio improvement 6 months after surgery correlated with the MRC grade change from baseline to 12 months, with a correlation coefficient of 0.813. CONCLUSION: EDX parameters improved significantly postoperatively, and the CMAP ratio improvement 6 months after surgery correlated with the clinical outcomes at 1 year. The results of perioperative EDX might help establish long-term treatment plans for patients who undergo nerve transfer surgery.

Surgical Reconstruction of Isolated Upper Trunk Brachial Plexus Birth Injuries in the Presence of an Avulsed C5 or C6 Nerve Root.

BACKGROUND: Avulsion of either the C5 or C6 root with intact middle and lower trunks in brachial plexus birth injury is rare. In these cases, only 1 proximal root is available for intraplexal reconstruction. The purpose of the present study was to determine the outcomes of these patients when single-root reconstruction was balanced across the anterior and posterior elements of the upper trunk. METHODS: We performed a retrospective cohort study of prospectively collected data for patients with brachial plexus birth injury who underwent primary nerve reconstruction between 1993 and 2014. Patients were included who had isolated upper-trunk injuries with intact middle and lower trunks. The study group had avulsion of either the C5 or C6 root. The control group had neuroma-in-continuity or ruptures of the upper trunk. Outcomes were assessed with use of the Active Movement Scale and the Brachial Plexus Outcome Measure. The Wilcoxon signed-rank test was utilized to evaluate changes across treatment. RESULTS: Ten patients with brachial plexus birth injury were included in the avulsion cohort. Surgical reconstruction entailed neuroma resection and nerve grafting from the single available root balanced across all distal targets with or without spinal accessory-to-suprascapular nerve transfer. Significant improvements were observed across treatment for both the avulsion and control groups in terms of shoulder abduction, shoulder flexion, external rotation, elbow flexion, and supination. At a mean follow-up of 54.5 ± 8.8 months, patients in the avulsion group achieved Active Movement Scale scores of 6.8 ± 0.4 for elbow flexion and 6.5 ± 0.9 for shoulder flexion and abduction, with lesser recovery observed in external rotation (3.3 ± 2.8). All patients available for Brachial Plexus Outcome Measure assessments demonstrated functional movement. CONCLUSIONS: In the setting of avulsion of 1 upper-trunk root, nerve reconstruction by grafting of the upper trunk from the other upper-trunk root provides improved movement, high Active Movement Scale scores, and satisfactory function according to the Brachial Plexus Outcome Measure. These data provide support for a strategy that ensures the entire upper trunk is adequately reconstructed in the setting of upper-trunk lesions. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Relationship between Trunk Control and Upper Extremity Function in Children with Obstetric Brachial Plexus Palsy.

PURPOSE: This study aimed to assess sitting skills and trunk control in children with obstetric brachial plexus palsy (OBPP) and investigate the effect of these skills on upper extremity function. METHODS: A total of 106 children with OBPP aged 10-18 months were included in this study. Injury severity was determined with Narakas Classification. The Gross Motor Function Measurement Sitting Sub-scale was used to assess sitting skills, while the Sitting Assessment Scale was used to evaluate the trunk control. The upper extremity functions were assessed with using the Active Movement Scale and the Modified Mallet Score. RESULTS: As the severity of injury increased, sitting skills and trunk control values decreased (p = .0001). In addition, upper extremity function decreased with the decreasing sitting skills and trunk control (p = .0001). CONCLUSION: Rehabilitation approaches should involve approaches that aim to increase trunk control in addition to programs targeting the extremity function in children with OBPP.

Jitter patterns in conventional concentric needle electromyography recordings of regenerating motor units.

BACKGROUND: The time interval between two potential components of the same motor unit potential (MUP) is measured for jitter analysis. Enhanced jitter is generally thought to result from impaired neuromuscular transmission as occurs in myasthenia gravis or during reinnervation. METHODS: Within a database of conventional video-electromyography (EMG) recordings 4 MUP with peculiar jitter patterns were identified. In 1 spontaneously discharging MUP, massive and chaotic jitter was seen with a mean consecutive difference (MCD) of 9.3 ms. In 2 spontaneously discharging MUP a certain potential subgroup jittered relative to the other part(s) of the MUP (MCD 2.0 and 3.3 ms). A jittering satellite was detected in a fourth voluntarily recruited MUP (MCD 0.6 ms). RESULTS: These different jitter patterns recorded with conventional EMG technique may mainly result from dysmyelination. CONCLUSIONS: A new look at the contribution of dysmyelination to abnormal jitter is also warranted in single fiber EMG recordings.

Upregulation of JHDM1D-AS1 alleviates neuroinflammation and neuronal injury via targeting miR-101-3p-DUSP1 in spinal cord after brachial plexus injury.

BACKGROUND: Neuroinflammation in the spinal cord following acute brachial plexus injury (BPI) remains a vital cause that leads to motor dysfunction and neuropathic pain. In this study, we aim to explore the role of long non-coding RNA JHDM1D antisense 1 (JHDM1D-AS1) in mediating BPI-induced neuroinflammation and neuronal injury. METHODS: A total brachial plexus root avulsion (tBPRA) model in adult rats and IL-1ß-treated motor neuron-like NSC-34 cells and LPS-treated microglia cell line BV2 were conducted for in vivo and in vitro experiments, respectively. The expressions of JHDM1D-AS1, miR-101-3p and DUSP1, p38, NF-κB, TNF-α, IL-1ß, and IL-6 were detected by RT-PCR and western blot seven days after tBPI. Immunohistochemistry (IHC) was used to detect neuronal apoptosis. CCK8 assay, Tunel assay and LDH kit were used for the detection of neuronal injury. The targeted relationships between JHDM1D-AS1 and miR-101-3p, miR-101-3p and DUSP1 were verified by RNA immunoprecipitation (RIP) and dual-luciferase reporter gene assay. RESULTS: We found significant downregulated expression of JHDM1D-AS1 and DUSP1 but upregulated expression of miR-101-3p in the spinal cord after tBPI. Overexpression of JHDM1D-AS1 had a prominent neuroprotective effect by suppressing neuronal apoptosis and microglial inflammation through reactivation of DUSP1. Further exploration revealed that JHDM1D-AS1 may act as a competitive endogenous RNA targeting miR-101-3p, which bound on the 3'UTR of DUSP1 mRNA. In addition, overexpression of miR-101-3p could reverse the neuroprotective effects of JHDM1D-AS1 upregulation by blocking DUSP1. CONCLUSIONS: JHDM1D-AS1 exerted neuroprotective and anti-inflammatory effects in a rat model of tBPI by regulating miR-101-3p/DUSP1 axis.

Perineural spread to the brachial plexus: a focused review of proposed mechanisms and described pathologies.

BACKGROUND: Perineural spread (PNS) is an emerging mechanism for progressive, non-traumatic brachial plexopathy. We aim to summarize the pathologies (tumor and infection) shown to have spread along or to the brachial plexus, and identify the proposed mechanisms of perineural spread. METHODS: A focused review of the literature was performed pertaining to pathologies with identified perineural spread to the brachial plexus. RESULTS: We summarized pathologies currently reported to have PNS in the brachial plexus and offer a structure for understanding and describing these pathologies with respect to their interaction with the peripheral nervous system. CONCLUSIONS: Perineural spread is an underrepresented entity in the literature, especially regarding the brachial plexus. It can occur via a primary or secondary mechanism based on the anatomy, and understanding this mechanism helps to support biopsies of sacrificial nerve contributions, leading to more effective and timely treatment plans for patients.

Primary cancer location predicts predominant level of brachial plexopathy.

BACKGROUND: Changes in radiation therapy practice and cancer incidence bring into question prior evidence suggesting that radiation therapy predominantly injures the brachial plexus upper trunk, while tumor invasion typically injures the lower trunk. METHODS: We reviewed electrodiagnostic brachial plexopathy reports in cancer survivors for predominant trunk involvement, injury mechanism (tumor invasion vs radiation), and primary cancer location. RESULTS: Fifty-six cases of cancer-associated brachial plexopathy were identified. There was no relationship between injury mechanism and brachial plexus injury level. However, primary cancer location superior/inferior to the clavicle increased the odds of predominantly upper/lower trunk involvement by a factor of 60.0 (95% confidence interval: 7.9, 1401, respectively). CONCLUSIONS: Cancers superior/inferior to the clavicle increase the likelihood of predominantly upper/lower trunk plexopathy, respectively, regardless plexus injury mechanism. These findings contrast with older work, possibly due to more precise radiation therapy techniques and increased incidence of radiosensitive head and neck cancers.

Trapezius Transfer to Restore Shoulder Function in Traumatic Brachial Plexus Injury: Revisited and Modified.

Background: Trapezius transfer has shown promise to restore shoulder movements and has stood through the passage of time. We here in describe a modification of trapezius transfer technique and review the current literature available. Methods: The modified trapezius transfer in which the trapezius muscle is extended with folded tensor fascia lata graft and attached as distally possible to the deltoid insertion was done in twelve patients at tertiary health care centre in India. Post-operative splinting and staged physiotherapy were given. Results: Results were described in the form of improvement in degree of shoulder abduction and Disabilities of the Arm, Shoulder and Hand (DASH) score. Six months post-surgery there were improvement in shoulder abduction and DASH score with mean 116 degrees (10-180 degree) and 38 (23-58) respectively. One patient showed poor results due to poor compliance in post-operative period. There were no major complications observed. Conclusions: The modified technique of trapezius transfer described here is a feasible option with good biomechanical outcomes. The technique is simple and can be adopted easily by emerging brachial plexus surgeon as a technique for secondary reconstruction of shoulder joint.

Chondrodesis of the wrist in children with severe paralytic hand deformities.

We examined the anatomical and clinical results of a new wrist subphyseal arthrodesis method called chondrodesis, which relies on resorbable suture-bone fixation for children with severe paralytic hand deformities and does not require fixation devices or bone grafting. Four children's wrists underwent the procedure, resulting in three successful wrist bone fusions. The wrists were stabilized by joint fusion in 4-5 months in good positions, ranging from neutral to extension 15°, while still allowing the forearm to keep growing since the radial growth plate remained open as of the last follow-up. The procedure improved hand function (House score, Raimondi score) and appearance. It also increased control over gripping motions with the operated hand, and even restored key pinch ability in one of the patients. The youngest patient was not able to achieve bone fusion at the key sites and will need further corrective procedures at a later and more optimal age. This novel procedure is appealing because of its technical reproducibility, low cost, encouraging outcomes, ease of rehabilitation, and because it spares the physeal cartilage.

Assessment of Motor Repertoire in 3- to 5-Month-Old Infants With Obstetric Brachial Plexus Lesion.

PURPOSE: The aim of this study was to define the movement characteristics and postures of infants with obstetric brachial plexus lesion. METHODS: The study group included 20 infants with obstetric brachial plexus lesion and a control group of 20 infants with normal neurological outcome, aged 9 to 17 weeks postterm. Infants were evaluated by global and detailed general movements assessment. RESULTS: There were no significant differences between the motor optimality scores of the 2 groups. However, there were some differences in terms of concurrent movements and the posture. Infants with obstetric brachial plexus lesion demonstrated more excitement bursts, head rotation, hand-knee contact, rolling, and few finger posture and postural asymmetry, and performed jerky movements when compared with the control group. CONCLUSIONS: Obstetric brachial plexus lesion did not affect the quality of fidgety movements of the infants but leads to compensatory movements in concurrent movements on the unaffected sides.

Brachial plexus birth injuries and the association between pre-procedure and post-procedure pediatric outcomes data collection instrument scores and narakas classification.

BACKGROUND: The brachial plexus is a network of nerves exiting the spinal cord through the fifth, sixth, seventh, and eighth cervical nerves (C5-C8) as well as the first thoracic nerve (T1) to conduct signals for motion and sensation throughout the arm. Brachial plexus birth injuries (BPBI) occur in 1.5 per 1,000 live births. The purpose of this study was to determine the perceived change in musculoskeletal health-related quality of life of brachial plexus patients utilizing the Pediatric Outcomes Data Collection Instrument (PODCI). PODCI scores were examined along with the patient's procedure history (surgical or Botulinum Toxin), extent of involvement and demographics. PATIENTS: A total of 81 patients from two to eighteen years of age from nine different states met the inclusion criteria of having a pre-procedure and post-procedure PODCI score along with a Narakas score from 2002-2017. These patients were seen at the Brachial Plexus Center, which is an interdisciplinary clinic at a large academic medical centerMETHODS: This retrospective study utilized PODCI data collected annually during their regular brachial plexus clinic visits. Upper extremity (UE) and global functioning (GFx) scores pre- and post-procedure were stratified by Narakas Classification. Data were analyzed using paired t-test and ANOVA testing. RESULTS: Patients with a Brachial Plexus Birth Injury (BPBI) had lower PODCI scores for UE and GFx when compared with the pediatric normative scores for age-matched healthy children. Scores in both UE and GFx domains were higher after procedure in the groups of Narakas I and IV. There was significant correlation between UE and GFx scores and documented first PODCI score (2 years of age) and age at intervention (5 years of age). CONCLUSION: Procedures increased the perceived quality of life for children with a BPBI and increased their overall PODCI scores for both UE and GFx.

Acupuncture Induces Reduction in Limbic-Cortical Feedback of a Neuralgia Rat Model: A Dynamic Causal Modeling Study.

Background: Neuropathic pain after brachial plexus avulsion remained prevalent and intractable currently. However, the neuroimaging study about neural mechanisms or etiology was limited and blurred. Objective: This study is aimed at investigating the effect of electroacupuncture on effective connectivity and neural response in corticolimbic circuitries during implicit processing of nociceptive stimulus in rats with brachial plexus pain. Methods: An fMRI scan was performed in a total of 16 rats with brachial plexus pain, which was equally distributed into the model group and the electroacupuncture group. The analysis of task-dependent data determined pain-related activation in each group. Based on those results, several regions including AMY, S1, and h were recruited as ROI in dynamic causal modeling (DCM) analysis comparing evidence for different neuronal hypotheses describing the propagation of noxious stimuli in regions of interest and horizontal comparison of effective connections between the model and electroacupuncture groups. Results: In both groups, DCM revealed that noxious stimuli were most likely driven by the somatosensory cortex, with bidirectional propagation with the hypothalamus and amygdala and the interactions in them. Also, the 3-month intervention of acupuncture reduced effective connections of h-S1 and AMY-S1. Conclusions: We showed an evidence that a full connection model within the brain network of brachial plexus pain and electroacupuncture intervention reduces effective connectivity from h and AMY to S1. Our study for the first time explored the relationship of involved brain regions with dynamic causal modeling. It provided novel evidence for the feature of the organization of the cortical-limbic network and the alteration caused by acupuncture.

Comparison of neuropathic pain characteristics associated with total brachial plexus injury before and after surgical repair: A retrospective study.

OBJECTIVES: The goal of this study was to compare clinical characteristics of neuropathic pain associated with total brachial plexus injury before and after surgeries and to correlate possible contributing factors concerning to the pain prognosis. PATIENTS AND METHODS: Thirty patients with both total brachial plexus injury and neuropathic pain were included. Neuropathic pain was evaluated in terms of pain intensities, symptoms and regions. Pain intensities were evaluated by a visual analogue scale. The Neuropathic Pain Symptoms Inventory questionnaire and body maps were used to compare the pain symptoms and regions. Demographic data, injury and repair information were evaluated to analyze the possible factors influencing the prognosis. RESULTS: The average pain score of all participants was 7.13 ± 2.46 preoperatively and 5.40 ± 2.08 postoperatively. All patients were divided into Pain Relief Group and Pain Aggravation Group. Older age (p = 0.042), machine traction injury (p = 0.019)and nerve transplantation(p = 0.015) seemed to be related with pain aggravation. Paroxysmal pain was aggravated after surgical repairs (p = 0.041), while paresthesia/dysesthesia improved after surgery (p = 0.003). The permanent component of the pain (spontaneous pain) did not show any significant change (p = 0.584). Pain in C5 (p < 0.001) and C6 (p = 0.031) dermatomes got relieved after surgery. CONCLUSION: This study revealed the neuropathic pain of most patients with total brachial plexus injury was alleviated after neurosurgery, and the pain prognosis of different symptoms and regions varied after the nerve repair.

Contralateral C7 transfers: An innovative approach to improving peripheral neuropathic pain after traumatic brachial plexus injury with C5 rupture and avulsion of C6, C7, C8 and T1. A case series study.

OBJECTIVES: Peripheral neuropathic pain is a common and disabling problem after traumatic brachial plexus injury with global plexopathy secondary to C5 rupture and avulsion of C6, C7, C8, and T1. The purpose of this paper is to evaluate restoration of sensation and pain levels before and after targeted muscle reinnervation to the hand using contralateral C7 nerve transfers in patients who have traumatic brachial plexus injuries with C5 rupture and avulsion of C6, C7, C8, and T1. PATIENTS AND METHODS: This paper presents a retrospective review of the outcomes of the surgical management of 11 patients with global plexopathy with C5 rupture and avulsion from C6 to T1 roots. Ten of the patients had peripheral neuropathic pain. Mean follow-up was 6.9 years. RESULTS: Sensory recovery to the median nerve territory was returned in 10 out of 11 patients. Pain and quality of life were improved in the majority. CONCLUSION: Contralateral C7 nerve transfers may restore sensation to the median nerve territory with concurrent improvement in pain and some function in a limited number of patients for whom no other treatment options exist.

Low interrater reliability of brachial plexus MRI in chronic inflammatory neuropathies.

INTRODUCTION: Magnetic resonance imaging of the brachial plexus shows nerve thickening in approximately half of the patients with chronic inflammatory demyelinating polyneuropathy (CIDP) and multifocal motor neuropathy (MMN). The reliability of qualitative evaluation of brachial plexus MRI has not been studied previously. METHODS: We performed an interrater study in a retrospective cohort of 19 patients with CIDP, 17 patients with MMN, and 14 controls. The objective was to assess interrater variability between radiologists by using a predefined scoring system that allowed the distinction of no, possible, or definite nerve thickening. RESULTS: Raters agreed in 26 of 50 (52%) brachial plexus images; κ-coefficient was 0.30 (SE 0.08, 95% confidence interval 0.14-0.46, P < .0005). DISCUSSION: Our results provide evidence that interrater reliability of qualitative evaluation of brachial plexus MRI is low. Objective criteria for abnormality are required to optimize the diagnostic value of MRI for inflammatory neuropathies.

Backpack palsy and other brachial plexus neuropathies in the military population.

Brachial plexus neuropathy is often seen in the military population, especially due to pressure (backpack palsy, BPP) or idiopathic (neuralgic amyotrophy, NA). We aimed to gain insight in the disease characteristics of soldiers with brachial plexus neuropathies in the Dutch military population and to compare disease characteristics between patients with BPP and NA. In this retrospective chart review study we aimed to include all patients with brachial plexus neuropathy, who presented in the Joint Military Hospital between 1 January, 2011 and 31 December, 2016. We calculated the incidence of NA and BPP and Chi-square tests or Student t tests were performed for differences in patient characteristics between NA and BPP. We included 127 patients, 63 with BPP, 45 with NA, 10 with traumatic brachial plexus neuropathy, and 9 with other plexopathy. The incidence of brachial plexus neuropathy was 50/100 000 person years overall, 25/100 000 person years for BPP, and 18/100 000 person years for NA. Patients in the BPP group differed from the NA with regard to pain (BPP 41% vs NA 93%, P = .000), atrophy (13% BPP vs 29% NA, P = .049), and sensory symptoms (83% BPP vs 44% NA, P = .000). In the BPP group 90% had incomplete recovery and in the NA group 78%. Our study showed a high incidence of BPP and NA in the military population and suggests recovery is not so benevolent as previously thought. Future research is necessary to improve insight and outcome of military patients with brachial plexus neuropathies.

Elbow flexion reconstruction with nerve transfer or grafting in patients with brachial plexus injuries: A systematic review and comparison study.

INTRODUCTION: Posttraumatic brachial plexus (BP) palsy was used to be treated by reconstruction with nerve grafts. For the last two decades, nerve transfers have gained popularity and believed to be more effective than nerve grafting. The aim of this systematic review was to compare elbow flexion restoration with nerve transfers or nerve grafting after traumatic BP injury. METHODS: PRISMA-IPD structure was used for 52 studies included. Patients were allocated as C5-C6 (n = 285), C5-C6-C7 (n = 150), and total BP injury (n = 245) groups. In each group, two treatment modalities were compared, and effects of age and preoperative interval were analyzed. RESULTS: In C5-C6 injuries, 93.1% of nerve transfer patients achieved elbow flexion force ≥M3, which was significantly better when compared to 69.2% of nerve graft patients (p < 0.001). For improved outcomes of nerve transfer patients, shorter preoperative interval was a significant factor in all injury patterns (p < 0.001 for C5-C6 injuries and total BP injuries, p = 0.018 for C5-C6-C7 injuries), and young age was a significant factor in total BP injury pattern (p = 0.022). CONCLUSIONS: Our analyses showed that nerve transfers appear superior to nerve graftings especially in patients with a C5-C6 injury. Unnecessary delays in surgery must be prevented, and younger patients may have more chance for better recovery. LEVEL OF EVIDENCE: Level II.

Evaluation of functional outcomes after brachial plexus injury.

Major nerve injuries such as those of the brachial plexus present a significant challenge for both rehabilitation and evaluation of outcome. With these often complex and multi-faceted injuries, correct selection of outcome measures is important. Healthy nerve function in humans heightens our interactions with the world, creating quality and enjoyment through our experiences of movement and touch. Therefore, assessments should be holistic and representative of all of these features. This article considers the assessment and evaluation of all of the features of nerve injury: sensorimotor, sensation (including that of pain), function and the psychosocial aspects. Current practice is described and combined with clinical experience and research findings to provide suggestions and recommendations for the selection of the most appropriate tools for use with this patient group.

Recovery of shoulder abduction in traumatic brachial plexus palsy: a systematic review and meta-analysis of nerve transfer versus nerve graft.

Brachial plexus palsy is a surgically manageable condition. Re-animating the shoulder is a high priority for restoring upper extremity function. Methods for reinnervating injured nerves include the transfer of a healthy nerve or fascicle distal to the site of injury, or grafting a healthy sensory nerve to restore motor function. Studies aiming to compare these two techniques for restoring shoulder abduction have yielded conflicting results. We conducted a systematic review and meta-analysis following the PRISMA guidelines. We reviewed the PubMed database for studies comparing nerve transfer and nerve grafting for shoulder abduction published by December 2018. Outcomes using the Medical Research Scale (MRC) for muscle strength were assessed using a random effects model meta-analysis. Five studies comprising a total of 212 patients (n = 158, nerve transfer; n = 54, nerve grafts) were used for the analysis. The rate of functional recovery of shoulder function was slightly better for nerve transfer (n = 114/158, 72%) than for nerve graft patients (n = 36/54, 67%). However, this was not statistically significant (OR 1.34, 95% CI 0.27-6.72, I2 = 62.9%). Nerve transfer and grafting are similarly effective in terms of shoulder abduction. Future prospective studies are needed to validate our results and identify the optimal shoulder re-animation strategy in patients with brachial plexus injuries.