End-to-side nerve repair in peripheral nerve injury

In peripheral nerve injury, end-to-side neurorrhaphy has been reported as an alternative in cases that the proximal nerve stump is not accessible. Several hypotheses have been proposed to explain peripheral nerve regeneration after end-to-side neurorrhaphy. Recent evidence suggests that nerve regeneration occurs by collateral sprouting. Although a great number of humoral factors have been identified, molecular mechanism of nerve regeneration after end-to-side neurorrhaphy has not been completely clarified yet. The goal of this technique is to provide satisfactory functional recovery for the recipient nerve, without any deterioration of the donor nerve function. End-to-side technique has been investigated in detail in both experimental and clinical studies. Only a limited number of reported cases in clinical practice, until today, can reveal that end-to-side technique may become a viable means of repairing peripheral nerves in certain clinical situations.     

End-to-side nerve suture--a technique to repair peripheral nerve injury.

End-to-side nerve suture (ETSNS) has until recently been extensively researched in the laboratory animal (rat and baboon). Lateral sprouting from an intact nerve into an attached nerve does occur, and functional recovery (sensory and motor) has been demonstrated. We have demonstrated conclusively that ETSNS in the human is a viable option in treating peripheral nerve injuries, including injuries to the brachial plexus. Among the many advantages of this new technique are: (i) simple and short operation; (ii) shorter recovery time--suture is done closer to the target organs; (iii) nerve grafts to bridge injured gaps are eliminated, reducing the morbidity of nerve surgery to a minimum; (iv) innervation of paralysed muscles, for which there was previously thought to be no hope of recovery, opens up many new treatment options; and (v) certain aspects of nerve function and regeneration, unknown until recently, open new horizons and understanding. ETSNS has given us new dimensions in the management of peripheral nerve injuries.     

多功能生长因子Pleiotrophin与周围神经损伤的研究进展

原癌基因Pleiotrophin于1989年被发现,在肿瘤发生发展和中枢神经系统内起着重要作用.最近的研究表明:Pleiotrophin分子信号很可能参与周围神经损伤后脊髓神经元的保护、促进轴突再生、轴突再生导向、骨骼肌的神经再支配4个环节,并可能在轴突再生导向和骨骼肌的神经再支配中发挥关键作用.随着研究的深入,Pleiotrophin基因有望成为提高周围神经修复效果和重建神经肌连接的基因调控靶点.     

周围神经损伤修复方法的研究进展

【摘要】〓回顾周围神经损伤的修复方法,从传统的断端吻合法、神经移植法、神经导管法、神经延长法,到组织工程法、基因工程法,修复手段日益完善,但周围神经的功能恢复仍然没有突破性的进展。各种修复技术各有优点,也都存在一定的局限性。因此,提高神经再生的速度和质量、完善现有的修复方法和寻找新的修复方法,仍然是一个巨大的挑战。     

Anatomy and physiology of peripheral nerve injury and repair

The management of peripheral nerve injury continues to be a major clinical challenge. Despite advancements in microsurgical technique, results after nerve repair have been unpredictable and dis appointing. The management of these nerve injuries relies on having a thorough understanding of peripheral nerve anatomy. This is the basis of the classification schemes by Seddon and Sunderland, in which the prognosis of nerve injuries varies depending on the degree of injury to their substructures. The most recent advances in the management of peripheral nerve injuries rely on the ability to manipulate the pathophysiologic processes triggered by nerve injuries and regeneration. End-to-end primary repair should be sought whenever a tension-free repair can be attained. If there is a significant nerve gap, use of nerve autograft remains the gold standard. In nerve injuries where a nerve autograft is not possible, the use of nerve allograft, as well as autogenous, biodegradable, and synthetic nerve conduits has shown promising results in experimental studies.     

Techniques of peripheral nerve repair.

At present, the principles of microsurgical reconstruction of the peripheral nerve incorporate a clear understanding of the pathophysiology of the peripheral nerve, accurate preoperative assessment of the lesion, aggressive early treatment to avoid irreversible atrophy of the end organ, use of nontraumatic microtechniques for optimal alignment of individual fascicular bundles, introduction of a minimum amount of foreign material at the suture line, resection of the scar-producing epineurium, total avoidance of tension at the suture line, and placement of the nerve repair in a well-vascularized soft tissue bed. If tension is eliminated, a minimal amount of suture material is required to repair the nerve ends, because the bundles are maintained in anatomical alignment by a fibrin clot. We have reviewed the various nerve repair methods, stressing that with strict attention to microsurgical technique, the surgeon can hope to maximize reinnervation. Although the importance of all aspects of careful surgical technique cannot be overemphasized, we believe that it is unlikely that improved clinical results will come from further refinements in microsurgical techniques. We are not limited by a working knowledge and understanding of the details of the neurobiology and the neurochemistry of nerve regeneration.     

周围神经损伤临床修复技术概况

周围神经损伤的修复，过去长期以来都是肉眼下操作，进行简单的神经外膜缝合，因得不到神经束的精确对合，以致神经再生效果很差。近10余年来，我国的周围神经外科事业随着机械化程度的提高和交通事业的发展，周围神经损伤发生率大幅度的上升，以及显微外科技术的应用而有了长足的发展，极大地推动了周围神经外科的基础研究和修复水平，丰富     

水凝胶在周围神经损伤修复领域的应用研究进展

作为临床常见创伤性疾病之一,周围神经损伤(peripheral nerve injury,PIN)由于损伤后再生速度缓慢,常会引起神经疼痛、异常反射、自主神经紊乱等,甚至出现感觉运动障碍严重影响机体功能。即便作为治疗金标准,自体神经移植也存在供区有限、供体损伤等局限性,极大地限制了其临床应用效果。因此,制备适合临床实践的人工神经移植物成为PIN治疗的未来发展趋势,修复损伤缺损和促进神经再生也成为组织工程和再生医学的研究热点。近年来,对人工神经导管(nerve guidance conduits,NGCs)在神经再生修复领域进行了广泛研究,其中支架材料和内填充物作为神经导管的核心要素也成为研究的重点,新材料应用、包埋干细胞/前体细胞、开发负载营养因子及载药缓释系统均取得了一系列成果。本研究探讨了水凝胶及其相关衍生材料在PIN修复领域中的应用进展,为推动组织工程和临床医学的相关研究提供新的思路。     

甲基泼尼松龙对周围神经修复的影响

目的 探讨甲基泼尼松龙对周围神经再生的促进作用及剂量选择。方法 28只成年SD雌性大，取股外侧切口，钳夹造成双侧坐骨神经损伤。创伤后1h起分别肌注不同剂量的甲基泼尼松龙或对照溶液，并间隔3h维持肌注，持续24h。按肌注剂量的不同随机分为大剂量组（首剂150mg/kg）、中剂量组（首剂30mg/kg）、小剂量组（首剂15mg/kg）和对照组（生理盐水与0．9％苯甲醛1：1混合液）。肌注后观察各组大鼠一般状态，记录术前及术后4周大鼠足印，测定坐骨神经功能指数（SFI0；术后4周显露双侧坐骨神经测定神经传导速度（NCV）；对取得的数据进行统计学分析。同时行神经横切片组织学观察。结果 中、小剂量组SFI均值优于大剂量组和对照组，但差异无显著性意义；中、小剂量组神经诱发电位引出率（100％）明显高于对照组（57．1％）（P＜0．01）；小剂量组NCV值优于其他三组，而且差异具有显著性意义（P＜0．05）；大剂量组大鼠均出现明显神经精神症状，有1只因感染死亡，3只4侧出现局部感染，其他三组未见明显异常。中、小剂量组神经横切片轴索再生情况优于大剂量组及对照组。结论 甲基泼尼松龙的全身应用可有效促进周围神经损伤后再生，但剂量选择不应过大，以减少感染及精神症状等副作用。     

FK 506加速周围神经损伤修复后的功能恢复

目的：探讨FK506对大鼠坐骨神经横断伤修复后肢体功能恢复的影响。方法：45只SD大鼠高位切断坐骨神经后原位缝合，术后实验组（25只）用FK506灌胃，对照组（20只）不给药，于术后第1、2、3、5个月检测术肢比目鱼肌肌湿重恢复率，小腿三头肌肌力恢复率，坐骨神经功能指数及皮层体感诱发电位（SEEP）的潜伏期，结果：实验组肢体功能恢复时间较对照组提前大约2个月。结论：FK506可加速周围神经横断伤修复后肢体功能的恢复。     

Use of nerve conduits in peripheral nerve repair

Studies on nerve conduits for peripheral nerve regeneration have concentrated on the manipulation of various conduit materials to avoid sacrificing native nerve in the clinical situation. With the proliferation of available nerve growth-stimulating factors, the focus is shifting experimentally toward molecular biologic manipulation, with the addition of these materials as substrates within the conduit. The clinical use of conduits has concentrated on the use of autogenous tissue, with a few examples of polyglactin (PGA) mesh and silicone. Ultimately, as yet, conduit material does not seem to have a profound effect on outcome. Substrate manipulation has not yet had clinical application. An important problem that remains, both experimentally and clinically, is overriding the size of the maximal gap that can be bridged successfully, as well as obtaining good functional sensory and motor recovery, compared with the use of nerve grafts. Advances in molecular biology may reveal further details about the nerve growth phenomenon, the precise sequencing of the substrate materials that are effective in promoting nerve growth, and when they should be applied. Advances in chemical engineering may provide additional biologically stable materials that have the ability to integrate growth-enhancing agents or factors into the lumen of the conduit.     

Progress of peripheral nerve repair

Study on repair of peripheral nerve injury has been proceeding over a long period of time.With the use of microsurgery technique since 1960s, the quality of nerve repair has been greatly improved.In the past 40 years,with the continuous increase of surgical repair methods,more progress has been made on the basic research of peripheral nerve repair.     

Microsurgical repair of peripheral nerve injuries in the upper extremity.

Microsurgical techniques have been used for peripheral nerve repair at the University of Colorado since 1975. The authors prefer a modified fascicular repair. The rationale is discussed, surgical technique described, and a preliminary review of functional results presented.     

自组装多肽凝胶联合可降解神经导管修复长节段周围神经损伤

[目的]探讨自组装多肽凝胶联合可降解神经导管修复长节段周围神经损伤的可行性及效果。[方法]选取新西兰大白兔48只,体重1 500 g左右,雌雄不限,按随机数字法分为A:自体神经移植组、B:神经导管+NSCs+NGF组、C:神经导管+IKVAV多肽凝胶+NSCs+NGF组;选取兔坐骨神经,暴露后人为造成10 mm缺损损伤,按照分组分别进行移植修复。术后3、6、9、12周观察兔下肢溃疡形成及愈合情况;术后12周对各组动物进行坐骨神经肌电图检查,处死后取标本观察神经再生情况、小腿三头肌湿重、组织学观察及神经干细胞存活情况。[结果]术后3组动物均出现不同程度的足底溃疡,恢复情况以A组最好,C组次之,B组最差。术后12周神经肌电图、肌肉湿重检测均显示自体神经移植组神经功能恢复良好,优于其余两组(P<0.05)。组织学观察显示C组神经再生情况接近自体神经移植组,明显优于B组。术后12周荧光显微镜下观察到在神经损伤处有绿色荧光蛋白(GFP)荧光表达,神经干细胞仍然存活。[结论]自组装多肽凝胶联合可降解神经导管修复长节段周围神经损伤可以取得良好的疗效。     

Clinical application of axonal repair technique for treatment of peripheral nerve injury

Althoughtheapplicationoffinemicrosurgicaltechniquewithepineurialorperinurialstitcheshasimprovedtheoperativeefficacyofperipheralnerveinjuriestoa greatextent ,thetotaloutcomeofnerverepair ,however ,isnotallthatcouldbedesired .1Thecruxliesmostlyinthemisdirectionoftheregeneratingaxonscausedbythedisorganizationoftheinternalfascicularstructure .2DeMedinaceli3describedanewtechniqueofnerverepair,termed ”cellsurgery”,withwhichtheperipheralnerveisrepairedattheaxonallevelbyminimizingphysicalandchemical…     

Percussive injury to peripheral nerve in rats.

Weights were dropped on rat sciatic nerves. Teased fibers and light and electron micrographs of nerves removed between 10 minutes and 2 weeks later were examined. Axonal alterations were seen 10 minutes after injury, and subsequently interruption of axonal continuity with preservation of the basal lamina was apparent. Dissolution of myelin began within 30 minutes and progressed. At 14 days, a segment of some large fibers was devoid of myelin and, by 2 weeks, remyelination had commenced. Demyelination of significant number of fibers was always accompanied by Wallerian degeneration of other fibers of the same nerve. Percussive injury of nerves caused a mixed lesion in which the early and late pathological features were clearly distinguishable from those following crush or compression by a cuff. Any explanation of the transient interruption of function that has been described following such an injury is at present speculative.     

周围神经移植修复脊髓损伤的实验研究

目的：探讨自体坐骨神经移植修复脊髓损伤的可行性。方法：将58只雌性Wistar大鼠分为二组，实验组：采用显微外科技术，将50只大鼠于T13水平切除左半侧脊髓10mm，再取右侧坐骨神经10mm移植到脊髓缺损处，近端接脊髓，远端接马尾，分别于术后2、4、6、8、12、22周在光镜和电镜下观察移植处坐骨神经、吻合口远端马尾神经、左后肢坐骨神经再生情况，并用摄像机记录患肢功能恢复情况。对照组：8只大鼠，于13水平切除左半侧脊髓10mm，不移植坐骨神经，观察脊髓缺损远端马尾神经和左右肢坐骨神经再生情况。结果：对照组坐骨神经的轴突及髓鞘部分崩解，密度降低，无再生轴突形成。实验组术后4周电镜下偶见移植处坐骨神经髓鞘及轴突形成，术后8周光镜及电镜下可见较多细的有髓神经纤维，22周时接近正常；同时观察到左后肢坐骨神经再生；大鼠后肢功能部分恢复，肌力达3级。结论：大鼠脊髓损伤后有再生能力，周围神经移植修复脊髓损伤是可行的。     

Primary peripheral nerve repair in the hand and upper extremity.

A small consecutive series of primary nerve repairs in civilian injuries demonstrates that normal two-point discrimination and stereognosis can be anticipated not only in digital-nerve injuries but in mixed sensory and motor nerve injuries. Motor return follows and approaches normal in most patients. During the study period, 15 delayed repairs of mixed nerve lacerations were done. Two-point discrimination and stereognosis did not return to normal in any of the patients with mixed-nerve injuries or in one quarter of those with sensory-nerve injuries. Motor return never graded better than 3 on a scale of 0-4. Therefore, this author feels primary repair is superior to secondary repair and that almost all civilian injuries can be made surgically clean by debridement.