SD大鼠腰神经根的解剖学观察

目的　为从腰神经根途径开展脊髓损伤后肢体运动功能重建的研究提供解剖依据。 方法　对10只SD大鼠灌注后进行显微解剖研究,并对30只SD大鼠进行手术中观察和测量,观察腰神经根的解剖特点。 结果　SD大鼠腰神经根共有6对,其中L2~4组成股神经支配股四头肌,L5~6组成坐骨神经支配股后肌群,腰髓约平对T12,13及L1、2水平。腰神经前根1束较细,后根2束较粗,腰神经前、后根出硬膜后,有各自独立的硬膜囊包绕后直至后根神经节处。 结论　SD大鼠腰神经根解剖特征与人类不同。     

基因工程细胞移植治疗坐骨神经损伤的研究进展

<正>坐骨神经是人体最粗大的神经,主要支配股二头肌长头、半腱肌、半膜肌和大收肌、小腿及足的全部肌肉以及除隐神经支配区以外的小腿与足的皮肤感觉。在损伤严重的情况下,远段发生的轴突坏死、髓鞘分解消失和神经鞘膜增生等,即"瓦勒变性"过程,引起股后部肌肉及小腿和足部所有肌肉全部瘫痪,导致膝关节不能屈、踝关节与足趾运动功能完全丧失,呈足下垂,且小腿后外侧和足部感觉丧失,足部出现神经营养性改变,可严重影响伤者的日常生活。坐骨神经损伤为临床常见且术后修复     

人股二头肌肌内神经分布和神经入肌点定位

目的查清人股二头肌长头和短头的肌内神经分布和神经入肌点定位,为其肌移植提供形态学依据。方法(1)观察20具尸体股二头肌长头和短头的神经分支数量,拟将坐骨结节与股骨外上髁连线分4等份,观测神经入肌点水平。(2)用3具童尸股二头肌做Sihler's肌神经染色,观察肌内神经分布。结果(1)长头神经来自坐骨神经胫侧,神经肌支一支型占22.5%,两支型72.5%,三支型5.0%,入肌点位于1/4区占22.1%,2/4区57.1%,3/4区20.8%。短头神经来自坐骨神经腓侧,一支型占95.0%,两支型5.0%,入肌点在肌的近部浅面。(2)长、短头肌内神经分支各形成一条神经支配带,横过各肌束中段。结论股二头肌长头和短头有单独神经支配。长头神经支配多见于两支型,神经入肌点多见于2/4区。     

神经电生理对臀部肌注致坐骨神经损伤的诊断价值

目的：探讨神经电生理检测对臀部肌注致坐骨神经损伤的诊断意义。方法：对34例患者进行腓总神经、胫神经的神经传导速度（NCV）检测，并对胫骨前肌、腓肠肌、股二头肌长短头、椎旁肌L4-S1进行针极肌电图检测。结果：34例病例中，腓总神经传导速度NCV异常29例（85．3％），胫神经13例（38．2％），腓总神经、胫神经同时异常8例（23．5％）。经统计学处理，与正常对照组比较差异有显著意义（P〈0．01）。肌电图示，有失神经电位改变者：胫前肌为29例（85．3％），股二头肌短头为29例（85．3％），腓肠肌为13例（38．2％），股二头肌长头为13例（38．2％）。结论：神经电生理检测对臀部肌注致坐骨神经损伤的诊断可提供客观依据。     

正常青年人自然步态下肢肌的表面肌电图分析◆

背景：肌肉的生物电活动是人体的能动部分,可反映人体运动的功能。 目的：观察和分析正常青年人在自然步态中下肢肌肉的表面肌电活动。 方法：采用美国NORAXON公司生产的 TELEMYO 2400R G2表面肌电图仪对30例正常青年人在平地自然行走时,其双下肢股直肌、胫前肌、股二头肌和腓肠肌内侧进行测试,分析在正常步态中受试肌群表面肌电信号的变化规律。 结果与结论：正常青年人平地自然步行中,其双下肢股直肌、胫前肌、股二头肌和腓肠肌内侧的肌电随步态周期呈活动与静止周期性变化,左右侧同名肌肉交替活动;平均肌电振幅、平均肌电积分、平均频率、中位频率值最大的是腓肠肌内侧,其余由大到小依次是胫前肌,股二头肌,股直肌,右左腿分布规律一致;右侧腓肠肌内侧平均肌电振幅、平均频率、中位频率值均明显低于左侧(P < 0.05);受试肌的时域、频域值波动在一定范围。提示正常青年人自然步态中下肢肌群肌电活动呈节律性和右左侧交替活动;在受试肌中腓肠肌内侧的肌电活动最强;腓肠肌内侧的肌电活动存在着优势侧与非优势侧的轻度差别;下肢肌肌电活动的时域、频域值在一定范围波动。      

神经肌电图检查对足下垂患者病因诊断的回顾性分析

目的:通过神经肌电图检查对足下垂患者的临床资料、发病特点、病因诊断进行回顾性分析,为以后临床诊断、治疗提供依据。方法:收集我院2016年9月至2018年1月门诊无明显外伤的足下垂患者20例,对患侧下肢行神经及相关肌肉检测,通过所得数据分析足下垂患者患病原因。结果:7例诊断为腓总神经病,其中4例以腓骨小头上-下段传导速度减慢、动作电位波幅下降超过50%,为不良姿势、体位导致,3例为局部肿物压迫导致腓骨小头处卡压;7例以腓骨长肌、胫后肌、臀中肌、腰椎旁肌肌神经源性损害为主,诊断为腰5神经根病;6例为腓总神经、胫神经动作电位波幅下降,腓骨长肌、股二头肌长头神经源性损害,臀中肌、腰椎旁肌肌电图未见异常,诊断为坐骨神经病。结论:神经肌电图检查在足下垂患者的病因诊断中具有重要临床意义。     

一例罕见的47,XXX女性假肥大型肌营养不良症

患者　女 ,10岁。因走路不稳易摔跤、上楼梯困难及小腿肥大就诊。患儿系足月顺产 ,生长发育较同龄儿童落后 ,智力、发育正常。查体 :神志清楚 ,皮肤巩膜无黄染 ,浅表淋巴结不肿大 ,心脏听诊无异常 ,肝、脾未触及。步态呈鸭步 ,躯干、骨盆和四肢的肌肉萎缩 ,翼状肌、小腿腓肠肌肥大 ,未引出病理反射 ,Gower's征阳性。心电图示心肌损害 ,右肱二头肌和右胫前肌肌电图显示肌源性损害。血液生化检显示患者肌酸激酶 10 10 3U / L (正常参考值 15～ 15 0 U/ L ) ,乳酸脱氢酶 6 4 3U/ L (正常参考值 180～ 4 30 U/ L ) ,谷草转氨酶 14 4 U/ L (…     

快肌与慢肌失神经支配后的形态学变化

目的:探讨快肌(胫前肌)与慢肌(比目鱼肌)在失神经支配过程中的形态学差异。方法:本研究拟采用大鼠坐骨神经离断模型,通过组织病理学系统分析失神经支配过程中胫前肌与比目鱼肌在形态学方面的变化。结果:在坐骨神经损伤后不同时间点,将比目鱼肌的萎缩程度与胫前肌相比,显示比目鱼肌的萎缩程度较胫前肌严重,主要表现在比目鱼肌的肌肉湿重比较小、肌纤维截面积比率较低、超微结构较不完整、运动终板破损较严重。结论:失神经支配后慢肌萎缩程度较快肌严重。     

多发性肌炎和皮肌炎患者的临床与肌电图分析

目的 :探讨多发性肌炎 (PM)和皮肌炎 (DM)病人的临床与肌电图特征。方法 :对 74例PM和DM临床与肌电图特征进行分析。结果 :首发症状以肌肉无力为最多见 (占 3 4% ) ,其他依次为皮肤损害 (占 3 1% ) ,发热 (占 13 % )。肌电图检查示肌原性损害 64例 ,神经原性损害 2例 ,异常率为 89%。主要表现为插入电位延长 (9% )、出现自发电位 (5 2 % ) ;MUP时限缩短 (74% )、MUP波幅降低 (6% ) ,多相波增多 (3 4% ) ;重收缩时波型异常 (4 5 % )及峰值波幅降低 (3 7% )。股四头肌、胫前肌及肱二头肌组阳性率显著高于外展拇短肌组 (P <0 0 5 ) ,胫前肌组MUP时限缩短阳性率最高 ,多相波增多阳性率胫前肌组最高。结论 :肌电图检查是诊断PM和DM的重要手段 ,选择股四头肌、胫前肌及肱二头肌进行EMG检查阳性率最高     

膝骨关节炎患者膝关节置换后下肢肌的表面肌电图变化

背景：膝骨关节炎患者膝关节置换后下肢肌功能恢复一直存在着争议。 目的：评价膝骨关节炎患者膝关节置换手术后下肢肌肉功能。 方法：应用TELEMYO 2400R G2表面肌电图遥测仪对25例双膝骨关节炎单膝关节置换后患者在平常自然步态下进行双下肢股直肌、胫前肌、股二头肌和腓肠肌内侧的表面肌电信号测试。在肌电图测试前,对患者双膝关节功能进行美国特种外科医院膝关节评分。 结果与结论：患者置换后美国特种外科医院膝关节评置换侧平均分91.44,其优良率达100%;未置换侧平均分54.52。置换侧在疼痛、关节功能方面有明显改善;膝关节置换后置换侧股直肌、胫前肌、股二头肌的肌电振幅、肌电积分、平均频率、中位频率的(平均值、最小值、最大值)与未置换侧相比差异无显著性意义(P > 0.05);置换侧腓肠肌内侧肌电振幅值及肌电积分值显著大于未置换侧(P < 0.05);置换侧腓肠肌内侧平均频率、中位频率与未置换侧相比差异无显著性意义(P > 0.05)。提示膝关节置换后置换侧的下肢肌没有恢复到正常的功能活动水平,因此膝关节置换后康复要特别重视患者的肌肉锻炼。中国组织工程研究杂志出版内容重点：人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程全文链接：     

Interaction between peripheral afferent activity and presynaptic inhibition of ia afferents in the cat

It has been demonstrated in man that the H-reflex is more depressed by presynaptic inhibition than the stretch reflex. Here we investigated this finding further in the alpha-chloralose-anesthetized cat. Soleus monosynaptic reflexes were evoked by electrical stimulation of the tibial nerve or by stretch of the triceps surae muscle. Conditioning stimulation of the posterior biceps and semitendinosus nerve (PBSt) produced a significantly stronger depression of the electrically than the mechanically evoked reflexes. The depression of the reflexes has been shown to be caused by presynaptic inhibition of triceps surae Ia afferents. We investigated the hypothesis that repetitive activation of peripheral afferents may reduce their sensitivity to presynaptic inhibition. In triceps surae motoneurones, we measured the effect of presynaptic inhibition on excitatory postsynaptic potentials (EPSPs) produced by repetitive activation of the peripheral afferents or by fast and slow muscle stretch. EPSPs evoked by single electrical stimulation of the tibial nerve or by fast muscle stretch were significantly depressed by PBSt stimulation. However, the last EPSP in a series of EPSPs evoked by a train of electrical stimuli (5-6 shocks, 150-200 Hz) was significantly less depressed by the conditioning stimulation than the first EPSP. In addition, the last part of the long-lasting EPSPs evoked by a slow muscle stretch was also less depressed than the first part. A single EPSP evoked by stimulation of the medial gastrocnemius nerve was less depressed when preceded by a train of stimuli applied to the same nerve than when the same train of stimuli was applied to a synergistic nerve. The decreased sensitivity of the test EPSP to presynaptic inhibition was maximal when it was evoked within 20 ms after the train of EPSPs. It was not observed at intervals longer than 30 ms. These findings suggest that afferent activity may decrease the efficiency of presynaptic inhibition. We propose that the described interaction between afferent nerve activity and presynaptic inhibition may partly explain why electrically and mechanically evoked reflexes are differently sensitive to presynaptic inhibition.     

脐带间充质干细胞移植可延缓大鼠失神经肌肉的萎缩

背景：周围神经断伤后生长缓慢,失神经支配的肌肉萎缩及运动终板纤维化,导致肢体功能不可逆障碍。脐带间充质干细胞已经广泛应用于多学科研究,但应用于周围神经损伤中延缓大鼠失神经肌肉萎缩鲜有报道。 目的：观察异种异基因脐带间充干细胞移植于大鼠离断坐骨神经断端,延缓失神经肌肉萎缩的效果。 方法：新鲜脐带采集于健康足月产妇,分离鉴定脐带间充质干细胞。制备大鼠坐骨神经SunderlandⅣ度损伤模型,去神经束5 mm,神经外膜修复,5 mm小间隙移植脐带间充质干细胞模型,对照组仅在小间隙内注入同体积生理盐水。测定大鼠坐骨神经功能指数,小腿三头肌湿质量,坐骨神经干潜伏期、动作电位传导速度、波幅,以及骨骼肌纤维横截面积维持率。 结果与结论：造模后4,8及12周,脐带间充质干细胞组大鼠坐骨神经功能指数、右侧小腿三头肌湿质量及骨骼肌纤维横截面积维持率均显著高于对照组(P < 0.05)。造模后12周肌电图显示,脐带间充质干细胞组大鼠坐骨神经干潜伏期显著低于对照组,动作电位传导速度及波幅显著高于生理盐水对照组(P < 0.001)。提示脐带间充质干细胞移植于大鼠离断的坐骨神经断端,可促进神经生长,延缓失神经肌肉萎缩,维持失神经肌肉形态及功能。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

Basic anatomical investigation of semitendinosus and the long head of biceps femoris muscle for their possible use in electrically stimulated neosphincter formation

Anal neosphincter formation with electrically stimulated gracilis muscle is used increasingly for the surgical treatment of fecal incontinence. An alternative to gracilis might be of interest if this muscle is not available. 30 semitendinosus muscles and 15 long heads of biceps femoris were investigated on human cadavers. In particular, the nerve and vascular supply of these muscles was studied, both representing basic factors for muscle transposition. The long head of biceps femoris m. was found to receive its dominant vascular supply from the first and second perforating artery and its nerve supply from one motor branch out of the sciatic nerve, both as described in literature. The examination of semitendinosus m., however, revealed new anatomical aspects in its vascular supply. In all cases semitendinosus m. was found to receive dominant vascular pedicles from the medial circumflex femoral artery close to the ischial tuberosity and the second perforating artery. The nerve supply consisted of two motor branches out of the sciatic nerve. Both muscles fulfilled several basic criterias for transposition to the anus. However, regarding these requirements, semitendinosus offered distinct advantages in comparison with the long head of biceps femoris. Due to its vascular and nerve topography, semitendinosus seems suitable to serve as an alternative to gracilis.     

Reflex changes in muscle spindle discharge during a voluntary contraction

1. This study was undertaken to determine whether low-threshold cutaneous and muscle afferents from mechanoreceptors in the foot reflexly affect fusimotor neurons innervating the plantar and dorsiflexors of the ankle during voluntary contractions. 2. Recordings were made from 29 identified muscle spindle afferents innervating triceps surae and the pretibial flexors. Trains of electrical stimuli (5 stimuli, 300 impulses per second) were delivered to the sural nerve at the ankle (intensity: 2-4 times sensory threshold) and to the posterior tibial nerve at the ankle (intensity: 1.5-3 times motor threshold for the small muscles of the foot). The stimuli were delivered while the subject maintained an isometric voluntary contraction of the receptor-bearing muscle, sufficient to accelerate the discharge of each spindle ending. This ensured that the fusimotor neurons directed to the ending were active and influencing the spindle discharge. The effects of these stimuli on muscle spindle discharge were assessed using raster displays, frequencygrams, poststimulus time histograms (PSTHs) and cumulative sums ("CUSUMs") of the PSTHs. Reflex effects onto alpha-motoneurons were determined from poststimulus changes in the averaged rectified electromyogram (EMG). Reflex effects of these stimuli onto single-motor units were assessed in separate experiments using PSTHs and CUSUMs. 3. Electrical stimulation of the sural or posterior tibial nerves at nonnoxious levels had no significant effect on the discharge of the 14 spindle endings in the pretibial flexor muscles. The electrical stimuli also produced no significant change in discharge of 11 of 15 spindle endings in triceps surae. With the remaining four endings in triceps surae, the overall change in discharge appeared to be an increase for two endings (at latencies of 60 and 68 ms) and a decrease for two endings (at latencies of 110 and 150 ms). The difference in the incidence of the responses of spindle endings in tibialis anterior and in triceps surae was significant (P less than 0.05, chi 2 test). 4. For both triceps surae and pretibial flexor muscles the electrical stimuli to sural or posterior tibial nerves had clear effects on the alpha-motoneuron pool, whether assessed using surface EMG or the discharge of single-motor units. Based on EMG recordings using intramuscular wire electrodes, the reflex effects differed for the gastrocnemii and soleus. 5. In this study, reflex changes in the discharge of human spindle endings were more difficult to demonstrate than comparable changes in the discharge of alpha-motoneurons.(ABSTRACT TRUNCATED AT 400 WORDS)     

NGF和GM1联合应用对去细胞异种神经支架移植后神经再生和修复的影响

为了探讨神经生长因子(NGF)和单唾液酸四己糖神经节苷脂(GM1)联合应用对去细胞异种神经支架移植后神经再生及功能恢复的影响,本研究将SD大鼠随机分为生理盐水对照组、NGF治疗组、GM1治疗组、NGF+GM1联合治疗组,选取兔胫神经进行化学萃取,形成去细胞异种神经支架桥接大鼠10mm坐骨神经缺损,移植前分别用等渗盐水(NS)、NGF液、GM1液或NGF+GM1液浸泡去细胞异种神经支架,术后各组大鼠术侧小腿肌内分别注射NS液、NGF液、GM1液或NGF+GM1液。术后4、8周行大体观察并用神经电生理、肌湿重、免疫组织化学等方法测定神经纤维再生及功能恢复情况。结果显示:在同一时间点,NGF+GM1联合治疗组坐骨神经运动传导速度恢复率、小腿腓肠肌复合动作电位波幅恢复率、小腿三头肌湿重恢复率均优于单独用药组(P<0.05);免疫组织化学结果显示NGF+GM1联合治疗组有大量再生有髓神经纤维顺畅地通过远端吻合口。本研究结果提示联合应用NGF和GM1可明显促进去细胞异种神经支架移植后的神经纤维再生与功能恢复。     

Effect of muscle length on phasic stretch reflexes in humans and cats.

1. This is a report of the effects at different muscle lengths of the muscle's immediate history on the tendon jerk and Hoffman (H)-reflex in triceps surae of human subjects and cats. 2. In adult human subjects the size of the tendon jerk was measured as electromyogram (EMG) and torque in response to a tendon tap. Before each test tap the muscle was conditioned by a maximum voluntary contraction carried out with the foot either plantarflexed or dorsiflexed by 30 degrees from the test position. After a contraction with the foot dorsiflexed, the subsequent reflex response was smaller than after a contraction with the foot plantarflexed. 3. The same conditioning procedure was carried out with the H-reflex. The reflex was elicited by transcutaneous electrical stimulation of the tibial nerve in the popliteal fossa. Here the reflex after a contraction with the foot dorsiflexed was larger than after plantarflexion. In other words, the effects of conditioning were the opposite for the tendon jerk and H-reflex. 4. The effects of muscle conditioning were tested over a range of muscle lengths. As the test length was made progressively longer, that is, the foot more dorsiflexed, the difference in size of the tendon jerk following the two forms of conditioning became less, whereas for the H-reflex it remained the same. 5. These findings were confirmed in cats anesthetized with alpha-chloralose. The tendon jerk was elicited by a quick stretch applied to the triceps surae muscle group, and the H-reflex represented by the monosynaptic reflex recorded from the central, cut end of the ventral root in response to electrical stimulation of the triceps nerve. Muscle conditioning consisted of a 1-s period of stimulation at 20 pulses/s, at fusimotor strength, of the peripheral end of the cut ventral root at a muscle length 5 mm longer or shorter than the test length. In the cat, as in human subjects, the effect of conditioning on the tendon jerk reversed at long muscle lengths, whereas the monosynaptic reflex showed no reversal. 6. It had been proposed previously that the effects of conditioning on stretch reflexes could be explained by development of slack in the intrafusal fibers of muscle spindles after a contraction at a longer-than-test length. The presence of slack lowers the resting discharge of spindles and reduces the afferent response to a tendon tap.(ABSTRACT TRUNCATED AT 400 WORDS)