一氧化氮合成酶在周围神经的表达

目的 研究一氧化氮合成酶（ｎｉｔｒｉｃ ｏｘｉｄｅ ｓｙｎｔｈａｓｅ,ＮＯＳ）的三种同工酶在大鼠坐骨神经中的表达和分布情况。方法 取１０只ＳＤ大鼠双侧正常坐骨神经,一侧用于Ｗｅｓｔｅｒｎ印迹检查,另外一侧用于免疫组化检查。结果 Ｗｅｓｔｅｒｎ印迹法中,用神经元型一氧化氮合成酶（ｎｅｕｒｏｎａｌ ＮＯＳ,ｎＮＯＳ）单抗和内皮细胞型一氧化氮合成酶（ｅｎｄｏｔｈｅｌｉａｌ ＮＯＳ,ｅＮＯＳ）单抗,分别发     

The use of magnetic resonance imaging to evaluate the accuracy of a handheld ultrasound machine in localizing the sciatic nerve in the popliteal fossa

BACKGROUND AND OBJECTIVE: Ultrasound has become an increasingly popular modality in facilitating the performance of peripheral nerve blocks. There is a paucity of data describing techniques of ultrasound-guided sciatic nerve blocks. By using magnetic resonance imaging (MRI) as a gold standard, the objective of this study was to describe the ability of a handheld ultrasound machine to accurately locate the sciatic nerve. METHODS: Ten patients were prospectively enrolled and placed in the prone position. By using a 4- to 7-MHz ultrasound transducer, the sciatic nerve was visualized in short axis between 5 to 10 cm above the popliteal crease. The distance from the skin to the nerve was measured by ultrasound, and a MRI lucent marker was placed at this site. This process was repeated in one additional location. The patient was then placed supine in the MRI scanner and short-axis T1-weighted images were obtained. On the MRI image, we recreated the 2 lines extending down from the markers using the distances previously measured by ultrasound. The point of intersection of these 2 lines represents the ultrasound-determined location of the sciatic nerve, which was then compared with the midpoint of the nerve complex on MRI. RESULTS: The sciatic nerve was easily visualized by ultrasound in all 10 patients. MRI showed the division of the sciatic nerve in 9 out of 10 patients. Ultrasound was able to confirm this division in 7 patients. The mean distance between the MRI and ultrasound midpoint location of the sciatic nerve was 2.9 +/- 1.3 mm. CONCLUSIONS: The data presented here suggest that the specific ultrasound machine evaluated in this study can accurately localize the sciatic nerve in the popliteal fossa.     

生物素葡聚糖胺观测周围神经局部轴突运输的实验研究

目的 研究神经示踪剂生物素葡聚糖胺（BDA）用于直观观察周围神经局部轴突运输的可行性。方法 （1）显露双侧兔坐骨神经，于实验侧及对照侧坐骨神经干注射不同浓度、不同剂量BDA，对照侧注射生理盐水，术后6、12、24、48h取样。于光镜及共聚焦显微镜下观察样本。（2）将兔左侧坐骨神经横断损伤并缝合，分别于术后1～6周于损伤近侧神经干注射10％BDA，12h后取标本观察。结果 10％BDA可清晰地在周围神经轴突内显像，操作简单，结果易于观察。同时，坐骨神经断伤术后3周时有明确的轴浆运输的恢复。结论 BDA神经干局部注射后能较清楚而直观地显示局部轴突运输的情况。     

Surgical anatomy of the sciatic nerve: A meta‐analysis

The sciatic nerve has varying anatomy with respect to the piriformis muscle. Understanding this variant anatomy is vital to avoiding iatrogenic nerve injuries. A comprehensive electronic database search was performed to identify articles reporting the prevalence of anatomical variations or morphometric data of the sciatic nerve. The data found was extracted and pooled into a meta‐analysis. A total of 45 studies (n = 7068 lower limbs) were included in the meta‐analysis on the sciatic nerve variations with respect to the piriformis muscle. The normal Type A variation, where the sciatic nerve exits the pelvis as a single entity below the piriformis muscle, was most common with a pooled prevalence of 85.2% (95%CI: 78.4–87.0). This was followed by Type B with a pooled prevalence of 9.8% (95%CI: 6.5–13.2), where the sciatic nerve bifurcated in the pelvis with the exiting common peroneal nerve piercing, and the tibial nerve coursing below the piriformis muscle. In morphometric analysis, we found that the pooled mean width of the sciatic nerve at the lower margin of the piriformis muscle was 15.55 mm. The pooled mean distance of sciatic nerve bifurcation from the popliteal fossa was 65.43 mm. The sciatic nerve deviates from its normal course of pelvic exit in almost 15% of cases. As such we recommend that a thorough assessment of sciatic nerve variants needs to be considered when performing procedures in the pelvic and gluteal regions in order to reduce the risk of iatrogenic injury. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1820–1827, 2016.     

Ultrasound examination and localization of the sciatic nerve: a volunteer study

BACKGROUND: Few studies have examined the use of ultrasound for sciatic nerve localization. The authors evaluated the usefulness of low-frequency ultrasound in identifying the sciatic nerve at three locations in the lower extremity and in guiding needle advancement to target before nerve stimulation. METHODS: In this prospective observational study, 15 volunteers underwent sciatic nerve examination using a curved ultrasound probe in the range of 2-5 MHz and a Philips-ATL 5000 unit (ATL Ultrasound, Bothell, WA) in the gluteal, infragluteal, and proximal thigh regions. Thereafter, an insulated block needle was advanced inline with the ultrasound beam to reach the nerve target, which was further confirmed by electrical stimulation. The quality of sciatic nerve images, ease of needle to nerve contact, threshold stimulating current, and resultant motor response were recorded. RESULTS: The sciatic nerve was successfully identified in the transverse view as a solitary predominantly hyperechoic structure on ultrasound in all of the three regions examined. The target nerve was visualized easily in 87% and localized within two needle attempts in all patients. Nerve stimulation was successful in 100% after two attempts with a threshold current of 0.42 +/- 0.12 (mean +/- SD) eliciting foot plantarflexion or dorsiflexion. CONCLUSIONS: These preliminary data show that a curved 2- to 5-MHz ultrasound probe provides good quality sciatic nerve imaging in the gluteal, infragluteal, and proximal thigh locations. Ultrasound-assisted sciatic nerve localization is potentially valuable for clinical sciatic nerve blocks.     

LLLT actives MMP-2 and increases muscle mechanical resistance after nerve sciatic rat regeneration

The purpose of this study was to analyze the low-level laser therapy (LLLT) on metalloproteinase expression and the mechanical strength of skeletal muscle regeneration after peripheral nerve injury. Rats were subjected to crush injury of the right sciatic nerve, followed by LLLT (830 nm, 35, 70, 140, and 280 J/cm²) for 21 consecutive days. Functional gait analysis was performed at weekly intervals and the animals were sacrificed after the last evaluation at day 21 for collection of the gastrocnemius muscles, which were submitted to analysis of resistance, and the tibialis anterior, for evaluation of metalloproteinase-2 (MMP-2). The results were statistically analyzed at a significance level of 5%. The irradiated groups showed a significant decrease in the sciatic functional index and a significant increase in the mechanical strength when compared to the injured group with no treatment (p?<?0.05), with no significant difference among the energy densities used. While no difference among groups was observed for the activity of MMP-2 in pro-active band, at the intermediate band, the activity was significantly higher (p?<?0.05) for the groups irradiated with 35, 70, and 140 J/cm², and at the active band, the activity was significantly more intense in the group irradiated with 280 J/cm². The present study demonstrated that injury of the sciatic nerve, with consequent muscle denervation, are benefited by the laser therapy, which restores neuromuscular function, active MMP-2 and increases the maximum breaking strength.     

Threatened lower extremity in a neonate from a severely constricting amniotic band: a case for limb salvage after a 6-year functional follow-up

A child presented at birth with a threatened lower limb from severe constriction band. Limb salvage was performed by emergency z-plasty reconstructions and subsequent sural nerve grafting to a fibrotic segmental deficit in the sciatic nerve. Follow-up over a 6-year period enables us to provide a favorable outlook with regard to functional use of the extremity and absence of chronic lymphedema, but she does have a significant limb length discrepancy.There is virtually no information on long-term functional outcome of such cases, although textbook teaching advises one to attempt emergency salvage of an extremity that is threatened by a severely constricting congenital amniotic band. Follow-up of our patient equips us with outcome information so that we can now better inform parents when once again faced with this problem in the neonate.     

周围神经65KD蛋白对培养鼠胚脊髓运动神经元的影响

目的 了解周围神经损伤后其远侧端特异性表达的65KD蛋白对鼠胚脊髓运动神经元的影响。方法 选用SD大鼠坐骨神经横断后二周的动物模型,自然凝胶系统电溶分析损伤后神经远侧端中的蛋白组分,将65KD蛋白区带胶务与14天鼠胚脊髓运动神经元联合培养。结果 损伤后二周的坐骨神经远侧端中特异性地出现表达增强的65KD蛋白;与含65KD蛋白区带胶条联合培养的脊髓运动神经元细胞存活数量多、突起生长旺盛。结论 坐骨神经损伤后其远侧端组织中65KD蛋白表达增强,该蛋白具有促进鼠胚脊髓运动神经元存活与突起生长的作用：     

125碘 - 辣根过氧化物酶追踪手术后神经

目的　研究12 5碘 辣根过氧化物酶 ( 12 5I HRP)追踪术后神经轴浆流的可行性 ;为临床应用放射性同位素研究神经再生提供实验依据。方法　 2 4只SD大鼠 ,按手术先后顺序分为两组。 ( 1)实验组 :于坐骨结节远端 0 .8cm处切断大鼠右侧坐骨神经后立即行端端缝合术。术后 4周 ,从右侧小腿三头肌内注射12 5I HRP。 ( 2 )对照组 :将12 5I HRP注射到大鼠右侧小腿三头肌内。于注射12 5I HRP 2 4h后 ,实验组取神经缝合口近段 0 .8cm神经干 ,对照组取右侧坐骨结节远端的坐骨神经 0 .8cm ;两组同时切取该段神经周围肌肉和左侧相应部位坐骨神经干 ,进行12 5碘放射性强度的г 计数。结果　对照组 ,注射侧坐骨神经干的12 5碘放射性强度是其它组织的 3 0倍以上。实验组 ,注射侧坐骨神经的12 5碘放射性强度是其周围肌肉和对侧坐骨神经的 6倍和 7倍。两组注射侧坐骨神经的12 5碘放射性强度和其它组织相比 ,差异均有显著性意义 (P <0 0 1)。　结论　12 5I HRP注入肌肉被神经末梢摄取后 ,经轴浆逆流可以通过神经缝合口到达神经近段 ;应用г 计数器可探测神经组织中的12 5碘放射性强度。     

Magnetic resonance microneurography of rabbit sciatic nerve on a 1.5-T clinical MR system correlated with gross anatomy

This study was performed to investigate the feasibility and accuracy of magnetic resonance (MR) microneurography of the rabbit sciatic nerve on a 1.5-T clinical MR system by correlation with the gross anatomy. The 3D T2-weighted imaging (3D-T2WI), 3D T2-weighted imaging plus spectral presaturation with inversion recovery (SPIR), and T1-weighted imaging (T1WI) of the sciatic nerve in ten rabbits were performed on a 1.5-T MR system. The radiological anatomy of the sciatic nerve was observed and correlated with the gross anatomy. The anterior-posterior diameter of the sciatic nerve trunk was measured on 3D T2WI and on gross anatomy. The T1 and T2 relaxation times were also measured with multiecho spin echo and mixed sequence, respectively. The tibial nerve and peroneal nerve in the sciatic nerve trunk in all ten rabbits could be clearly displayed on T2WI and T2WI. The fine branches of the gastrocnemius nerve, posterior femoral cutaneous nerve, and the posterior gluteal nerve could be clearly depicted on T2WI. The T1 and T2 relaxation times of the sciatic nerves were 915 and 40 ms, respectively. The anterior-posterior diameter of sciatic nerve trunk was measured grossly, and on T2WI was 3.17 +/- 0.21 mm and 3.15 +/- 0.19 mm, respectively. There was no statistically significant difference (t = 0.768, P = 0.462). With the 1.5-T clinical MR system, the microneurography of the sciatic nerve could be revisualized, and the finer structure of the sciatic nerve trunk could be clearly and accurately delineated.     

全髋关节置换及翻修术后坐骨神经损伤的原因探讨

目的 通过对655例行全髋关节置换及翻修术患者的回顾性分析，探讨术后出现坐骨神经损伤的原因并提出相应的预防措施。方法 1998年1月～2001年12月，对655倒髋关节病变的患者行手术治疗．其中全髋关节置换术587例，全髋关节翻修术68例，术后有9例出现坐骨神经损伤．发生率为1.37％。其中8例发生在全髋关节置换术后，1例发生在全髋关节翻修术后，9例患者中，男3例，女6例；年龄35～67岁，平均51岁，9例患者中4例因股骨头缺血性坏死、2例因先天性髋臼发育不良合并髋关节骨关节炎、1例因强直性脊柱炎合并髋部病变、1例因类风湿关节炎合并髋部病变、1例因全髋关节假体松动而行全髋关节置换术。非骨水泥固定8例，骨水泥固定1例。9例坐骨神经损伤的患者中．7例因肢体不等长而同时行下肢延长术．2例因髋部强直而同时行松解术，结果 9例术后出现坐骨神经损伤的患者．8例为单纯腓总神经损伤．临床表现为足不能背伸；1例为腓总神经和胫神经联合损伤．临床表现为足不能背伸和跖屈。术后随访6～48个月，平均31个月.其中8例患者术后半年坐骨神经功能全部恢复；1例患者术后半年坐骨神经功能仍未恢复．遂行切开探查松解术．探查术后1年坐骨神经功能部分恢复。结论 全髋关节置换及翻修术后坐骨神经损伤．多由下肢过度延长或机械性压迫所致，大多数不完全损伤可以恢复.     

Peripheral nerve lengthening by controlled isolated distraction: a new animal model.

We have developed a simple and effective animal model to study the distraction neurogenesis utilizing the sciatic nerve-lengthening technique in rats. The model allows macroscopic, physiological, and histological evaluation of the distraction site. Fourteen adult Harlan Sprague Dawley rats (300-350 g) were used in this study. A 10 mm segment of the right sciatic nerve of each animal in the nerve-lengthening group was resected. Gradual nerve lengthening was performed by advancing the proximal nerve stump at a rate of 1 mm/day. The proximal stump neuroma was then resected and a direct nerve anastomosis was performed. On the left side a standard autogenous nerve-grafting procedure was performed with a 10 mm segment of sciatic nerve used as an in situ nerve graft. Three months after the second surgery, the sciatic nerves were exposed and investigated by gross observation and EMG followed by histological processing and tissue analysis. Neomicrovascularization was observed surrounding the sciatic nerve anastomosis in all five specimens of the nerve-lengthening group as compared to the more white-colored scar tissue that was observed in the nerve-grafting group. The EMG results were similar for both groups. Histological studies of the lengthened nerves showed axon morphology equivalent to the grafted nerves. This study demonstrated a clear evidence of the successful nerve regeneration within a segmental nerve gap by nerve lengthening.     

Sciatic nerve palsy secondary to postoperative haematoma in primary total hip replacement

Sciatic nerve palsy is a recognised complication of primary total hip replacement. In our unit this complication was rare with an incidence of < 0.2% in the past ten years. We describe six cases of sciatic nerve palsy occurring in 355 consecutive primary total hip replacements (incidence 1.69%). Each of these palsies was caused by post-operative haematoma in the region of the sciatic nerve. Cases, which were recognised early and surgically-evacuated promptly, showed earlier and more complete recovery. Those patients for whom the diagnosis was delayed, and who were therefore managed expectantly, showed little or no recovery. Unexpected pain and significant swelling in the buttock, as well as signs of sciatic nerve irritation, suggest the presence of haematoma in the region of the sciatic nerve. It is, therefore, of prime importance to be vigilant for the features of a sciatic nerve palsy in the early post-operative period as, when recognised and treated early, the injury to the sciatic nerve may be reversed.     

嗅鞘细胞促进大鼠坐骨神经损伤后神经功能恢复

目的研究嗅鞘细胞（Olfactory ensheathing cells,OECs）移植对大鼠坐骨神经损伤后神经再生恢复的作用。方法取SD大鼠40只随机分成对照生理盐水（SAL）组和实验（OECs）组,予离断坐骨神经后直接予神经外膜缝合修复,在神经缝合处周围充填可吸收的明胶海绵,SAL组和OECs组明胶海绵内分别给予SAL和体外培养纯化的OECs;术后4、12周分别行大体观察,电生理检查和组织学检查。结果术后4、12周,SAL组和OECs组修复神经均有不同程度恢复,OECs组在运动神经传导速度、神经肌肉动作电位幅度和直径数据上有优于SAL组,但统计学上未见明显差异,而在有髓神经纤维数目方面明显优于SAL组（P〈0.05）。结论在本实验条件下,嗅鞘细胞（OECs）对大鼠坐骨神经损伤后的神经功能恢复有部分的促进作用。     

正常成人坐骨神经及其周围关系的高频超声研究

目的:探讨高频超声在正常成人坐骨神经检查中的应用价值。方法:应用高频超声检查60例共120条正常成人坐骨神经,男28例,女32例;年龄19～38岁,平均23.8岁。男女之间年龄、身高及体重差异均无统计学意义。采用横断扫查及纵断扫查,必要时结合宽景成像。在臀线处、股后部中段、腘窝上缘分别测量坐骨神经横截面积,并在每个横断面上观察坐骨神经与周围肌群关系;在臀部显示坐骨神经横断面后探头旋转90°,显示坐骨神经长轴,沿长轴从上到下纵切,结合宽景成像可以显示坐骨神经纵轴及与周围肌群关系。以男女分组和左右分组,分别求得臀线处中部、股后部中段、腘窝上缘处各组坐骨神经横截面积的均数和标准差,进行统计学分析。结果:高频超声对本组60例受检者120条股部坐骨神经均可清晰显示,但对臀部坐骨神经显示率较低,约为31.4%(21/66)。坐骨神经纵切面表现为条带状等回声或偏强回声,内可见数条平行偏强回声线,横断面呈边缘清楚的筛网状等回声或略强回声,可呈卵圆形、梯形、三角形及不规则形等,肌肉收缩时可见坐骨神经被动运动且形态可发生改变。28例男性56支坐骨神经与32例女性64支坐骨神经臀线处、股后部中段及腘窝上缘测得的横截面积,经统计学分析,男女之间对比差异有统计学意义;而左右侧对比差异无统计学意义。结论:高频超声可作为坐骨神经首选的影像检查方法。     

Incidence of Sciatic Nerve Palsy After Revision Hip Arthroplasty Through a Posterior Approach

Sciatic nerve palsy after revision hip arthroplasty is rare, but can have substantial impacts. The purpose of this study is to report the safety and reliability of limited sciatic nerve exposure during revision surgery. A retrospective case series of 350 revision hip surgeries performed by a single surgeon underwent sciatic nerve identification. In each case, the sciatic nerve was identified and tagged loosely with a Penrose drain. Three hundred forty-eight of 350 patients (99.4%) underwent successful revision hip arthroplasty. One patient developed a transient sensory palsy; and another patient, a delayed palsy. Both nerve palsies recovered by the 1-year visit. We advocate visual nerve identification and tagging in revision hip surgery as 1 possible method to potentially reduce the risks of sciatic nerve injury.     

兔坐骨神经损伤修复后骶交感神经节内c-ret mRNA表达的变化

目的　探讨兔坐骨神经损伤修复后骶交感神经节内c-retmRNA表达的变化。方法　用组织原位杂交方法观察兔坐骨神经损伤修复 1 ,3,7,1 4 ,30 ,6 0d后c -retmRNA在骶交感神经节内的表达。结果　兔坐骨神经损伤修复 3d后 ,在损伤侧骶交感神经节内c -retmRNA表达明显上调 ,在损伤后 7d达高峰 ,损伤后 1 4d与 30d仍维持较高水平 ,损伤后 6 0d基本恢复到正常水平。结论　C -retmRNA在兔坐骨神经损伤修复后骶交感神经节内表达的变化 ,提示在坐骨神经损伤修复后给予外源性胶质源性神经营养因子 (GDNF)可能有利于交感神经纤维的再生。     

Anterior approach to the sciatic nerve block: the effects of leg rotation

In the anterior approach to the sciatic nerve block, the femur often obstructs the passage of the needle toward the sciatic nerve. In this study, by using a human cadaver model, we assessed how internal and external rotation of the leg influences the accessibility of the sciatic nerve with the anterior approach. Ten lower extremities from five adult cadavers were studied. Needles were used to simulate the anterior approach to the sciatic nerve block. The effect of leg rotation on the needle plane required to reach the sciatic nerve was studied with legs in the neutral position and then with internal and external rotation (45 degrees) of the legs. During needle placement in the neutral position, the needle could not be fully advanced to the level of the sciatic nerve because of obstruction by the lesser trochanter in 80% of attempts. Medial redirection of the needle (10 degrees--15 degrees) allowed it to pass the lesser trochanter but brought the tip of the needle too medial to the sciatic nerve. Internal rotation of the leg facilitated passage of all needles inserted at the level of the lesser trochanter. We conclude that internal rotation of the leg may significantly facilitate needle insertion in the anterior approach to sciatic block.     

What is the minimum effective volume of local anesthetic required for sciatic nerve blockade? A prospective, randomized comparison between a popliteal and a subgluteal approach

For sciatic nerve blockade, no study has defined the optimal volume of local anesthetic required to block the nerve. The current, prospective, randomized investigation was designed to find a minimum volume of 1.5% mepivacaine required to block the sciatic nerve using the subgluteal and posterior popliteal approaches. A total of 56 patients undergoing foot surgery were randomly assigned to receive sciatic nerve block by means of a posterior subgluteal (group subgluteal, n = 28) or a posterior popliteal (group popliteal, n = 28) approaches. All blocks were performed with the use a nerve stimulator (stimulating frequency, 2 Hz, intensity 1.5-0.5 mA) and a perineural stimulating catheter. In all patients, plantar flexion of the foot was elicited at <0.5 mA, to maintain consistency among groups. The volume of local anesthetic used in each patient was based on the modified Dixon's up-and-down method. Complete anesthesia was defined as complete loss of pinprick sensation in the sciatic nerve distribution with concomitant inability to perform plantar or dorsal flexion of the foot 20 min after injection. The mean volume of local anesthetic required to block the sciatic nerve was 12 +/- 3 mL in the subgluteal group and 20 +/- 3 mL in the popliteal group (P < 0.05). The ED95 for adequate block of the sciatic nerve was 17 mL in the subgluteal group and 30 mL in the popliteal group. The authors conclude that a larger volume of local anesthetic is necessary to block the sciatic nerve at a more distal site (popliteal approach) as compared with a more proximal level (subgluteal approach).