Prevention of shoulder dystocia related birth injuries: Myths and facts

Traditionally, brachial plexus damage was attributed to excessive traction applied on the fetal head at delivery. Recently, it was proposed that most injuries occur spontaneously in utero. The author has studied the mechanism of neurological birth injuries based on 338 actual cases with special attention to(1) fetal macrosomia;(2) maternal diabetes; and(3) methods of delivery. There was a high coincidence between use of traction and brachial plexus injuries. Instrumental extractions increased the risk exponentially. Erb's palsy following cesarean section was exceedingly rare. These facts imply that spontaneous neurological injury in utero is extremely rare phenomenon. Literary reports show that shoulder dystocia and its associated injuries increased in the United States several-fold since the introduction of active management of delivery in the 1970's. Such a dramatic change in a stable population is unlikely to be caused by incidental spontaneous events unrelated to external factors. The cited investigations indicate that brachial plexus damage typically is traction related. The traditional technique which precludes traction is the optimal method for avoiding arrest of the shoulders and its associated neurological birth injuries. Effective prevention also requires meticulous prenatal care and elective abdominal delivery of macrosomic fetuses in carefully selected cases.

Motor neuron-specific RhoA knockout delays degeneration and promotes regeneration of dendrites in spinal ventral horn after brachial plexus injury

Dendrites play irreplaceable roles in the nerve conduction pathway and are vulnerable to various insults.Peripheral axotomy of motor neurons results in the retraction of dendritic arbors,and the dendritic arbor can be re-expanded when reinnervation is allowed.RhoA is a target that regulates the cytoskeleton and promotes neuronal survival and axon regeneration.However,the role of RhoA in dendrite degeneration and regeneration is unknown.In this study,we explored the potential role of RhoA in dendrites.A line of motor neuronal conditional knockout mice was developed by crossbreeding HB9~(Cre+)mice with RhoA~(flox/flox)mice.We established two models for assaying dendrite degeneration and regeneration,in which the brachial plexus was transection or crush injured,respectively.We found that at 28 days after brachial plexus transection,the density,complexity,and structural integrity of dendrites in the ventral horn of the spinal cord of RhoA conditional knockout mice were slightly decreased compared with that in Cre mice.Dendrites underwent degeneration at 7 and 14 days after brachial plexus transection and recovered at 28–56 days.The density,complexity,and structural integrity of dendrites in the ventral horn of the spinal cord of RhoA conditional knockout mice recovered compared with results in Cre mice.These findings suggest that RhoA knockout in motor neurons attenuates dendrite degeneration and promotes dendrite regeneration after peripheral nerve injury.

Comparing the Surgical Outcomes of Modified Quad and Triangle Tilt Surgeries to other Procedures Performed in Obstetric Brachial Plexus Injury

Purpose: To compare results from our surgical treatment experiences in children with obstetric brachial plexus injuries (OBPI), to those who have had other surgical treatments. Methods: We conducted a retrospective study in our medical records consisting of two groups of OBPI patients. Group 1: 26 OBPI children (16 girls and 10 boys), age range between 2.0 and 12.0 (mean age 6.9), who have undergone surgical treatments at other institutions between 2005 and 2010. Group 2: 45 OBPI children (20 boys and 25 girls), age between 0.7 and 12.9 (mean age 3.7), who have had modified Quad and triangle tilt surgical treatment between 2005 and 2010 at our institution. In both groups Mean modified Mallet scores and radiological scores were measured and compared. All measurements were made at least one year post surgery in both groups. Results: Post-operative mean modified Mallet score was 11.8 ± 2.4 in group 1 patients, whereas post-mean modified Mallet score was 20 ± 2.7 (P 0.0001) following modified Quad and triangle tilt surgeries in group 2 patients. Further, their radiological scores such as posterior subluxation, and glenoid version were 13.4 ± 21.3 and ﹣30.2 ± 19.1 in group 1, whereas 32.1 ±13.5 (P 0.0004), and ﹣16.3 ± 11.5 (P 0.008) in group 2 patients, when compared to normal values of 50, and 0 respectively. Conclusion: Patients who have had mod Quad and triangle tilt for OBPI obtained significantly better functional outcomes in modified total Mallet score as well as in radiological scores, when compared to those OBPI children, who underwent other procedures such as posterior glenohumeral capsulorrhaphy, biceps tendon lengthening, humeral osteotomy, anterior capsule release, nerve transfer/graft, botox and muscle/tendon transfer and release.

高分辨率磁共振成像对臂丛神经损伤的预测价值

目的探析高分辨率磁共振(MRI)成像对臂丛神经损伤(brachial plexus injury,BPI)的预测价值。方法对59例临床拟诊BPI的病例行高分辨MRI检查。根据年龄,将年龄≥65岁者纳入老年组,18~64岁者纳入青中年组。观察两组臂丛神经显像效果,计算臂丛神经成像评分、臂丛神经信噪比(signal-to-noise ratio,SNR)、对比度噪声比(contrast-to-noise ratio,CNR)和背景抑制评分,分析高分辨率MRI成像对不同年龄段BPI的预测价值。结果59例临床拟诊BPI病例中,MRI诊断为BPI 20例,其余正常。20例经MRI确诊BPI中,老年组7例和青中年组13例。老年组节前损伤2例(28.57%),节后损伤5例(71.43%);青中年组节前损伤5例(38.46%),节后损伤8例(61.54%)。两组病人臂丛神经成像评分由低到高依次为三维双回波稳态(3D-DESS)序列增强扫描、三维短时反转恢复快速自旋回波(3D SPACE)序列平扫、DESS序列平扫和SPACE序列增强扫描,且在干3、支5 DESS序列平扫、股6 DESS序列增强扫描及支5 SPACE序列增强扫描上,老年组臂丛神经成像评分明显低于青中年组(P<0.05)。两组SNR、CNR由低到高依次为DESS增强、SPACE平扫、DESS平扫和SPACE增强(P<0.05),两组背景组织抑制评分比较,SPACE增强最高,其次为DESS平扫,DESS增强和SPACE平扫最低(P<0.05)。老年组DESS序列增强扫描的SNR、CNR以及SPACE序列平扫、增强扫描的SNR、CNR均明显低于青中年组(P<0.05)。结论与青中年BPI病人相比,老年BPI病人臂丛神经成像评分、SNR与CNR更低,MRI 3D SPACE序列可清晰显示臂丛神经内部信号改变,同时降低神经周围背景组织信号干扰,对于显示神经损伤优势明显,值得临床优先选择。

磁共振神经成像对臂丛神经损伤的诊断效能及其与手术的一致性研究

目的 探讨磁共振神经成像(MRN)在臂丛神经损伤(BPI)中的诊断效能并评估其与手术的一致性。方法 回顾性分析35例BPI患者的影像资料及手术记录,以手术探查结果为对照标准,将术前MRN检查所见与手术探查结果进行比较。建立基于MRN征象的分类方法,分析M RN与手术探查结果的一致性。结果 MRN对35例患者神经损伤的定位评估与手术分型具有很高的符合率(9 1.4%),两者一致率良好(82.9%)。MRN诊断BPI的敏感度、特异度、准确度、阳性预测值、阴性预测值分别为92.7%、71.4%、90.3%、96.2%、55.6%。BPI的MRN分类与手术探查结果无明显差别,两者一致性良好(Kappa=0.743;Kappa=0.686)。结论 MRN能直观、准确地显示BPI的位置、形态及信号,MRN的神经分类方法与手术探查具有良好一致性,对BPI的诊断及治疗具有重要价值。

重复经颅磁刺激联合常规康复治疗臂丛神经损伤术后的效果

目的:观察研究重复经颅磁刺激(rTMS)结合常规康复治疗在单侧臂丛神经损伤(BPI)术后的效果。方法:选取广西医科大学第二附属医院康复医学科收治的BPI术后患者60例为研究对象,随机分为对照组与观察组各30例,对照组给予常规康复结合假性rTMS,观察组予常规康复结合初级运动区(M1)rTMS,疗程为3个月。在治疗前后对两组患者进行疼痛视觉模拟评分(VAS)、徒手肌力测试(MMT)、肩关节主动活动度测定(ROM)。结果:最终观察组纳入患者29例,对照组纳入28例。治疗前,两组患者一般情况、VAS、MMT、ROM比较,差异无统计学意义(P>0.05)。治疗3个月后,所有患者各项评定均较治疗前明显改善,差异有统计学意义(P<0.05),其中,观察组VAS较对照组明显降低,差异有统计学意义(P<0.05);观察组患侧肩关节前屈、后伸、外展主动活动度较对照组明显改善,差异有统计学意义(P<0.05);而两组患者的肌力恢复程度相当,差异无统计学意义(P>0.05)。结论:rTMS结合常规康复治疗能有效改善BPI术后患侧肩关节活动度,缓解疼痛。

江西省级顾玉东院士工作站创伤性臂丛神经损伤流行病学特点及治疗方案分析

目的分析江西省级顾玉东院士工作站创伤性臂丛神经损伤流行病学特点及治疗方案。方法收集2018年1月至2021年12月江西省级顾玉东院士工作站诊治的全部新发创伤性臂丛神经损伤病例,建立标准的数据采集表,采集病人性别、年龄、致伤原因、诊断、手术方案等数据,分析4年间院士工作站创伤性臂丛神经损伤的流行病学特点。结果全部符合条件的病人共58例,男47例,女11例,中位年龄43岁(8~78岁)。切割伤(29.31%)与交通事故伤(25.86%)为主要致伤原因。损伤部位以束支部多见(62.07%),其次为根干部节后损伤(22.41%)、根性撕脱伤(12.07%)。治疗方案选择中,仅有10.34%的病人选择非手术治疗,手术治疗者中以单纯臂丛神经松解术最多(67.24%),其次为神经移位术(18.97%),神经移位术中以副神经移位修复肩外展功能最为多见。结论江西省级顾玉东院士工作站创伤性臂丛神经损伤以中青年男性多见,交通事故伤与切割伤为主要致伤原因,大多数病人需要接受手术治疗。

超声下臂丛上干阻滞对肩关节镜肩袖损伤全麻患者血流动力学及应激反应的影响

目的探讨超声下臂丛上干阻滞对肩关节镜肩袖损伤全麻患者的应用价值。方法方便选取2020年3月—2022年11月济阳区人民医院收治的86例肩关节镜肩袖损伤全麻患者为研究对象,根据随机数表法划分为联合组和单一组,各43例。单一组施以全身麻醉,联合组施以超声下臂丛上干阻滞结合全麻。对比两组血流动力学、应激反应、麻醉药物用量。结果T_(2)时,联合组心率为(65.32±3.28)次/min、平均动脉压水平(84.32±3.27)mmHg较单一组(71.81±4.29)次/min、(86.81±4.05)mmHg低,差异有统计学意义(t=7.881、3.137,P均<0.05);T_(1)、T_(2)时,联合组肾上腺素、去甲肾上腺素水平较单一组低,差异有统计学意义(P均<0.05);联合组舒芬太尼、七氟烷用量较单一组少,差异有统计学意义(P均<0.05)。结论超声下臂丛上干阻滞应用于肩关节镜肩袖损伤全麻患者可稳定血流动力学,减少应激反应、麻醉药物用量。

艾司氯胺酮复合罗哌卡因在腋路臂丛神经阻滞中的应用效果

目的:观察艾司氯胺酮复合罗哌卡因在腋路臂丛神经阻滞中的应用效果。方法:回顾性分析2022年3月至2023年3月于该院接受腋路臂丛神经阻滞的76例手外伤患者的临床资料,根据麻醉方案不同将其分为对照组和研究组各38例。两组均行腋路臂丛神经阻滞,对照组应用罗哌卡因麻醉,研究组应用艾司氯胺酮复合罗哌卡因麻醉,比较两组不同时刻[入室时(T0)、阻滞15 min(T1)、阻滞30 min(T2)、术毕(T3)]血流动力学指标[平均动脉压(MAP)、心率]水平,臂丛神经阻滞效果,感觉与运动阻滞起效时间和持续时间,手术前后疼痛程度[视觉模拟量表(VAS)]评分,以及术后24 h不良反应发生率。结果:T0~T3时,两组MAP、心率水平比较,差异均无统计学意义(P>0.05);两组臂丛神经阻滞效果比较,差异无统计学意义(P>0.05);两组感觉与运动阻滞起效时间比较,差异均无统计学意义(P>0.05);研究组感觉与运动阻滞持续时间均长于对照组,差异有统计学意义(P<0.05);术后12、24 h,研究组VAS评分均低于对照组,差异有统计学意义(P<0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:艾司氯胺酮复合罗哌卡因应用于腋路臂丛神经阻滞可延长感觉与运动阻滞持续时间,降低VAS评分,效果优于单纯罗哌卡因麻醉。

Review of current reconstructive approaches for pan-brachial plexus injuries

Pan-brachial plexus injuries present a challenging clinical problem,resulting in severe impairment of motor and sensory function in the upper extremity.Although current literature has outlined several promising methodologies for treatment,a consensus has yet to be reached.In this review,we present three general approaches for reconstructing the upper extremity in these complex cases.

Electroacupuncture attenuates neuropathic pain after brachial plexus injury

Electroacupuncture has traditionally been used to treat pain, but its effect on pain following brachial plexus injury is still unknown. In this study, rat models of an avulsion injury to the left brachial plexus root （associated with upper-limb chronic neuropathic pain） were given electroacupuncture stimulation at bilateral Quchi （LIll）, Hegu （LI04）, Zusanli （ST36） and Yanglingquan （GB34）. After electroacupuncture therapy, chronic neuropathic pain in the rats＇ upper limbs was significantly attenuated. Immunofluorescence staining showed that the expression of β-endorphins in the arcuate nucleus was significantly increased after therapy. Thus, experimental findings indi- cate that electroacupuncture can attenuate neuropathic pain after brachial plexus injury through upregulating β-endorphin expression.

Human amniotic epithelial cell transplantation for the repair of injured brachial plexus nerve: evaluation of nerve viscoelastic properties

The transplantation of embryonic stem cells can effectively improve the creeping strength of nerves near an injury site in animals. Amniotic epithelial cells have similar biological properties as em-bryonic stem cells; therefore, we hypothesized that transplantation of amniotic epithelial cells can repair peripheral nerve injury and recover the creeping strength of the brachial plexus nerve. In the present study, a brachial plexus injury model was established in rabbits using the C6root avulsion method. A suspension of human amniotic epithelial cells was repeatedly injected over an area 4.0 mm lateral to the cephal and caudal ends of the C6 brachial plexus injury site （1 × 106 cells/mL, 3μL/injection, 25 injections） immediately after the injury. The results showed that the decrease in stress and increase in strain at 7,200 seconds in the injured rabbit C6 brachial plexus nerve were mitigated by the cell transplantation, restoring the viscoelastic stress relaxation and creep properties of the brachial plexus nerve. The forepaw functions were also signiifcantly improved at 26 weeks after injury. These data indicate that transplantation of human amniotic epithelial cells can effec-tively restore the mechanical properties of the brachial plexus nerve after injury in rabbits and that viscoelasticity may be an important index for the evaluation of brachial plexus injury in animals.

Small-worldness of brain networks after brachial plexus injury: a resting-state functional magnetic resonance imaging study

Research on brain function after brachial plexus injury focuses on local cortical functional reorganization,and few studies have focused on brain networks after brachial plexus injury.Changes in brain networks may help understanding of brain plasticity at the global level.We hypothesized that topology of the global cerebral resting-state functional network changes after unilateral brachial plexus injury.Thus,in this cross-sectional study,we recruited eight male patients with unilateral brachial plexus injury（right handedness,mean age of 27.9±5.4years old）and eight male healthy controls（right handedness,mean age of 28.6±3.2）.After acquiring and preprocessing resting-state magnetic resonance imaging data,the cerebrum was divided into 90 regions and Pearson’s correlation coefficient calculated between regions.These correlation matrices were then converted into a binary matrix with affixed sparsity values of 0.1–0.46.Under sparsity conditions,both groups satisfied this small-world property.The clustering coefficient was markedly lower,while average shortest path remarkably higher in patients compared with healthy controls.These findings confirm that cerebral functional networks in patients still show smallworld characteristics,which are highly effective in information transmission in the brain,as well as normal controls.Alternatively,varied small-worldness suggests that capacity of information transmission and integration in different brain regions in brachial plexus injury patients is damaged.

Total brachial plexus injury： contralateral C7 root transfer to the lower trunk versus the median nerve

Contralateral C7（cC7） root transfer to the healthy side is the main method for the treatment of brachial plexus root injury. A relatively new modification of this method involves cC7 root transfer to the lower trunk via the prespinal route. In the current study, we examined the effectiveness of this method using electrophysiological and histological analyses. To this end, we used a rat model of total brachial plexus injury, and cC7 root transfer was performed to either the lower trunk via the prespinal route or the median nerve via a subcutaneous tunnel to repair the injury. At 4, 8 and 12 weeks, the grasping test was used to measure the changes in grasp strength of the injured forepaw. Electrophysiological changes were examined in the flexor digitorum superficialis muscle. The change in the wet weight of the forearm flexor was also measured. Atrophy of the flexor digitorum superficialis muscle was assessed by hematoxylin-eosin staining. Toluidine blue staining was used to count the number of myelinated nerve fibers in the injured nerves. Compared with the traditional method, cC7 root transfer to the lower trunk via the prespinal route increased grasp strength of the injured forepaw, increased the compound muscle action potential maximum amplitude, shortened latency, substantially restored tetanic contraction of the forearm flexor muscles, increased the wet weight of the muscle, reduced atrophy of the flexor digitorum superficialis muscle, and increased the number of myelinated nerve fibers. These findings demonstrate that for finger flexion functional recovery in rats with total brachial plexus injury, transfer of the cC7 root to the lower trunk via the prespinal route is more effective than transfer to the median nerve via subcutaneous tunnel.

Effect of lentiviral vector-mediated overexpression of hypoxia-inducible factor 1 alpha delivered by pluronic F-127 hydrogel on brachial plexus avulsion in rats

Brachial plexus avulsion often results in massive motor neuron death and severe functional deficits of target muscles. However, no satisfactory treatment is currently available. Hypoxia-inducible factor 1α is a critical molecule targeting several genes associated with ischemia-hypoxia damage and angiogenesis. In this study, a rat model of brachial plexus avulsion-reimplantation was established, in which C5–7 ventral nerve roots were avulsed and only the C6 root reimplanted. Different implants were immediately injected using a microsyringe into the avulsion-reimplantation site of the C6 root post-brachial plexus avulsion. Rats were randomly divided into five groups: phosphate-buffered saline, negative control of lentivirus, hypoxia-inducible factor 1α(hypoxia-inducible factor 1α overexpression lentivirus), gel(pluronic F-127 hydrogel), and gel + hypoxia-inducible factor 1α(pluronic F-127 hydrogel + hypoxia-inducible factor 1α overexpression lentivirus). The Terzis grooming test was performed to assess recovery of motor function. Scores were higher in the hypoxia-inducible factor 1α and gel +hypoxia-inducible factor 1α groups(in particular the gel + hypoxia-inducible factor 1α group) compared with the phosphate-buffered saline group. Electrophysiology, fluorogold retrograde tracing, and immunofluorescent staining were further performed to investigate neural pathway reconstruction and changes of neurons, motor endplates, and angiogenesis. Compared with the phosphate-buffered saline group, action potential latency of musculocutaneous nerves was markedly shortened in the hypoxia-inducible factor 1α and gel + hypoxia-inducible factor1α groups. Meanwhile, the number of fluorogold-positive cells and ChAT-positive neurons, neovascular area(labeled by CD31 around av ulsed sites in ipsilateral spinal cord segments), and the number of motor endplates in biceps brachii(identified by α-bungarotoxin) were all visibly increased, as well as the morphology of motor endplate in biceps brachil was clear in the hypoxia-inducible factor 1α and gel + hypoxia-inducible factor 1α groups. Taken together, delivery of hypoxia-inducible factor 1α overexpression lentiviral vectors mediated by pluronic F-127 effectively promotes spinal root regeneration and functional recovery post-brachial plexus avulsion. All animal procedures were approved by the Institutional Animal Care and Use Committee of Guangdong Medical University, China.

Transplantation of human amniotic epithelial cells repairs brachial plexus injury:pathological and biomechanical analyses

A brachial plexus injury model was established in rabbits by stretching the C6 nerve root. Imme- diately after the stretching, a suspension of human amniotic epithelial cells was injected into the injured brachial plexus. The results of tensile mechanical testing of the brachial plexus showed that the tensile elastic limit strain, elastic limit stress, maximum stress, and maximum strain of the injured brachial plexuses were significantly increased at 24 weeks after the injection. The treatment clearly improved the pathological morphology of the injured brachial plexus nerve, as seen by hematoxylin eosin staining, and the functions of the rabbit forepaw were restored. These data indicate that the injection of human amniotic epithelial cells contributed to the repair of brachial plexus injury, and that this technique may transform into current clinical treatment strategies.

Nerve transfer helps repair brachial plexus injury by increasing cerebral cortical plasticity

In the treatment of brachial plexus injury, nerves that are functionally less important are transferred onto the distal ends of damaged crucial nerves to help recover neuromuscular function in the target region. For example, intercostal nerves are transferred onto axillary nerves, and accessory nerves are transferred onto suprascapular nerves, the phrenic nerve is transferred onto the musculocutaneous nerves, and the contralateral C7 nerve is transferred onto the median or radial nerves. Nerve transfer has become a major method for reconstructing the brachial plexus after avulsion injury. Many experiments have shown that nerve transfers for treatment of brachial plexus injury can help reconstruct cerebral cortical function and increase cortical plasticity. In this review article, we summarize the recent progress in the use of diverse nerve transfer methods for the repair of brachial plexus injury, and we discuss the impact of nerve transfer on cerebral cortical plasticity after brachial plexus injury.

Contralateral C7 transfer combined with acellular nerve allografts seeded with differentiated adipose stem cells for repairing upper brachial plexus injury in rats

Nerve grafting has always been necessary when the contralateral C7 nerve root is transferred to treat brachial plexus injury. Acellular nerve allograft is a promising alternative for the treatment of nerve defects, and results were improved by grafts laden with differentiated adipose stem cells. However, use of these tissue-engineered nerve grafts has not been reported for the treatment of brachial plexus injury. The aim of the present study was to evaluate the outcome of acellular nerve allografts seeded with differentiated adipose stem cells to improve nerve regeneration in a rat model in which the contralateral C7 nerve was transferred to repair an upper brachial plexus injury. Differentiated adipose stem cells were obtained from Sprague-Dawley rats and transdifferentiated into a Schwann cell-like phenotype. Acellular nerve allografts were prepared from 15-mm bilateral sections of rat sciatic nerves. Rats were randomly divided into three groups: acellular nerve allograft, acellular nerve allograft + differentiated adipose stem cells, and autograft. The upper brachial plexus injury model was established by traction applied away from the intervertebral foramen with micro-hemostat forceps. Acellular nerve allografts with or without seeded cells were used to bridge the gap between the contralateral C7 nerve root and C5–6 nerve. Histological staining, electrophysiology, and neurological function tests were used to evaluate the effect of nerve repair 16 weeks after surgery. Results showed that the onset of discernible functional recovery occurred earlier in the autograft group first, followed by the acellular nerve allograft + differentiated adipose stem cells group, and then the acellular nerve allograft group;moreover, there was a significant difference between autograft and acellular nerve allograft groups. Compared with the acellular nerve allograft group, compound muscle action potential, motor conduction velocity, positivity for neurofilament and S100, diameter of regenerating axons, myelin sheath thickness, and density of myelinated fibers were remarkably increased in autograft and acellular nerve allograft + differentiated adipose stem cells groups. These findings confirm that acellular nerve allografts seeded with differentiated adipose stem cells effectively promoted nerve repair after brachial plexus injuries, and the effect was better than that of acellular nerve repair alone. This study was approved by the Animal Ethics Committee of the First Affiliated Hospital of Sun Yat-sen University of China(approval No. 2016-150) in June 2016.

Evaluation of nerve transfer options for treating total brachial plexus avulsion injury： a retrospective study of 73 participants

Despite recent great progress in diagnosis and microsurgical repair, the prognosis in total brachial plexus-avulsion injury remains unfavorable.Insufficient number of donors and unreasonable use of donor nerves might be key factors. To identify an optimal treatment strategy for this condition, we conducted a retrospective review. Seventy-three patients with total brachial plexus avulsion injury were followed up for an average of 7.3 years. Our analysis demonstrated no significant difference in elbow-flexion recovery between phrenic nerve-transfer （25 cases）, phrenic nerve-graft （19 cases）, intercostal nerve （17 cases）, or contralateral C7-transfer （12 cases） groups. Restoration of shoulder function was attempted through anterior accessory nerve （27 cases）, posterior accessory nerve （10 cases）, intercostal nerve （5 cases）, or accessory ＋ intercostal nerve transfer （31 cases）. Accessory nerve ＋ intercostal nerve transfer was the most effective method. A significantly greater amount of elbow extension was observed in patients with intercostal nerve transfer （25 cases） than in those with contralateral C7 transfer （10 cases）. Recovery of median nerve function was noticeably better for those who received entire contralateral C7 transfer （33 cases） than for those who received partial contralateral C7 transfer （40 cases）. Wrist and finger extension were reconstructed by intercostal nerve transfer （31 cases）. Overall, the recommended surgical treatment for total brachial plexus-avulsion injury is phrenic nerve transfer for elbow flexion, accessory nerve ＋ intercostal nerve transfer for shoulder function, intercostal nerves transfer for elbow extension, entire contralateral C7 transfer for median nerve function, and intercostal nerve transfer for finger extension. The trial was registered at Clinical-Trials.gov （identifier： NCT03166033）.

Phrenic nerve transfer to the musculocutaneous nerve for the repair of brachial plexus injury: electrophysiological characteristics

Phrenic nerve transfer is a major dynamic treatment used to repair brachial plexus root avulsion. We analyzed 72 relevant articles on phrenic nerve transfer to repair injured brachial plexus that were indexed by Science Citation Index. The keywords searched were brachial plexus injury, phrenic nerve, repair, surgery, protection, nerve transfer, and nerve graft. In addition, we per-formed neurophysiological analysis of the preoperative condition and prognosis of 10 patients undergoing ipsilateral phrenic nerve transfer to the musculocutaneous nerve in our hospital from 2008 to 201 3 and observed the electromyograms of the biceps brachii and motor conduc-tion function of the musculocutaneous nerve. Clinically, approximately 28% of patients had brachial plexus injury combined with phrenic nerve injury, and injured phrenic nerve cannot be used as a nerve graft. After phrenic nerve transfer to the musculocutaneous nerve, the regener-ated potentials ifrst appeared at 3 months. Recovery of motor unit action potential occurred 6 months later and became more apparent at 12 months. The percent of patients recovering ‘ex-cellent’ and ‘good’ muscle strength in the biceps brachii was 80% after 18 months. At 12 months after surgery, motor nerve conduction potential appeared in the musculocutaneous nerve in seven cases. These data suggest that preoperative evaluation of phrenic nerve function may help identify the most appropriate nerve graft in patients with an injured brachial plexus. The func-tional recovery of a transplanted nerve can be dynamically observed after the surgery.