Compound nerve action potential of common peroneal nerve and sural nerve action potential in common peroneal neuropathy

To enhance the accuracy for determining the precise localization, the findings of the compound nerve action potentials (CNAPs) of the common peroneal nerve (CPN) were investigated in patients with common peroneal mononeuropathy (CPM) in the knee, and the sural sensory nerve action potentials (SNAPs) were also analyzed. Twenty-five patients with CPM in the knee were retrospectively reviewed. The findings of the CNAPs of the CPN recorded at the fibular neck and the sural SNAPs were analyzed. The lesion was localized at the fibular head (abnormal CNAPs) and at or distal to the fibular head (normal CNAPs). Seven patients were diagnosed as having a lesion at or distal to the fibular neck, and 18 cases were diagnosed as having a fibular head lesion. The sural SNAPs were normal in all the cases of lesion at or distal to the fibular neck. Among 18 cases of fibular head lesion, the sural SNAPs were normal in 7 patients: two cases of conduction block and 5 cases of mild axon loss. Eleven patients showed abnormal sural SNAPs. Of those, 9 cases were severe axon loss lesions and 2 patients were diagnosed as having severe axon loss with conduction block. The recording of the CNAPs may enhance precise localization of CPM in the knee. Moreover, the sural SNAPs could be affected by severe axonal lesion at the fibular head.     

Anatomical basis of the extraspinal cord compression

Knowledge of anatomical landmarks of the spinal cord within the vertebral foramen is essential to understand the pathogenesis of spinal cord compression by tumor growth. The spinal cord can spread in the intervertebral foramen, the epidural space, the vertebral body, and the posterior neural arch. The morphology of the spinal cord, the relations of the spinal roots with the vertebrae, the principal fiber tracts, the spinal membranes, and the arterial and venous distribution are described in order to explain and analyze signs and disorders caused by the most frequent tumors involved in spinal cord compression.     

骨间前神经综合征解剖学基础

目的 :探讨骨间前神经综合征发病解剖基础。方法 :48侧 (左右各 2 4侧 )成人防腐固定标本在肉眼或双目放大镜下解剖观察可能构成对骨间前神经卡压的解剖结构。结果 :有 6 6 .6 %的拇长屈肌副头由内上至外下斜过骨间前神经主干前方。横过骨间前神经的结构还有 :尺侧副血管 (48.3% ) ,指浅屈肌发出至拇长屈肌的小肌束或纤维束 (10 .4% )。骨间前神经与桡、尺骨的关系 :77%骨间前神经走在桡骨颈前方下行一段 ,长为 3.9cm(37侧 ,) ;16 .7%骨间前神经在桡、尺骨之间走行 ;6 .3%隔指深屈肌走在尺骨的前方。结论 :拇长屈肌副头、横过骨间前神经的肌束和纤维等结构可能是致骨间前神经综合征的解剖基础。     

Anatomical basis of transgluteal pudendal nerve block

Background  The pudendal nerve may become entrapped either within the pudendal canal or near the sacrotuberous ligament resulting in a partial conduction block. The goal of the present anatomical study was to assess a new transgluteal injection technique in terms of the precise injection site and the resulting distribution of the injected agent. Materials and methods  This study was carried out using eight fresh human cadavers. An epidural needle with a removable wing was inserted and the catheter position visualized using MRI. Through the catheter 10 ml of gadolinium contrast medium was injected into three of the cadavers. A further four cadavers were injected with latex and blue pigment and the pelvi-perineal area of each then separated from the trunk for freezing before being cut into 4–8 mm thick sections with an electric bandsaw. One final cadaver was injected with a mix of gadolinium (5 ml) and latex (5 ml) and both the MRI and anatomical procedures outlined above were performed. Results  Using MRI, we clearly imaged both the site of injection, near the trunk of the pudendal nerve, and the gadolinium contrast medium in different pelvic and perineal areas and around the fascia of the obturator internus and levator ani muscle. Concerning the anatomical study, latex was observed mainly around the sacrotuberous ligament, along the obturator internus muscle and in the perineal area in contact with the dividing branches of the pudendal nerve. The mixed injection of latex and gadolinium in the pudendal canal was found with the same localization between MRI and anatomical studies. Conclusion  This easily performed technique should provide a new approach for treating perineal neuralgia via pudendal nerve block in the consultation room without the need for computed tomography.     

Effects of sympathetic stimulation on C-fibre response after peripheral nerve compression: an experimental study in the rabbit common peroneal nerve

Non-myelinated C-fibre responses during sympathetic trunk stimulation were studied in rabbit common peroneal nerve 2 weeks after the nerve had been subjected to compression at 400 mmHg for 30 min. Our previous studies have demonstrated that during sympathetic trunk stimulation the compound action potential of uninjured somatic C-fibres is characterized by a reduced amplitude and an increased latency. In the present study, nerve compression changed the C-fibre response to sympathetic stimulation. Three out of eight nerves reacted to nerve compression by increased C-fibre compound action potential amplitude in response to sympathetic stimulation. In three other rabbits with compressed nerves the C-fibre action potential amplitude was unchanged, and in the remaining two rabbits the action potential amplitude was decreased during sympathetic stimulation. The action potential latency increased in all tested compressed C-fibres. The phenomenon of increased C-fibre amplitude during sympathetic activation has not been observed in uninjured nerves. As in uninjured nerves, noradrenaline infusion produced an increased C-fibre action potential amplitude and latency in six animals. Sympathetic stimulation did not affect the A-fibre response. These results indicate that sympathetic activity influences the conduction properties in C-fibres of somatic origin and that the response can be changed after a nerve injury. The findings may be of importance for the understanding of pain aggravation in different types of nerve injuries during increased sympathetic activity.     

腓浅神经痛诊治的解剖学基础(系列介绍之十五)

目的 介绍腓浅神经痛的诊断与局部注射的治疗方法。方法 选择门诊确诊为腓浅神经痛的患者18例，采用强的松龙混悬液加麻药局部注射神经穿出小腿深筋膜的部分的治疗方法。结果 所有病例皆在注射后短时完全止痛，多数病例一周后痊愈，少数病例经1～3次注射后痊愈。结论 对诊断明确的病例，采取强的松龙局部注射法，可以获得满意的疗效。     

骨间后神经受压的解剖学基础

目的阐明骨间后神经(PIN)卡压的原因及其手术治疗提供解剖基础。方法30侧尸体上肢标本,将PIN分为3段(即桡管段、旋后肌管段和旋后肌管后段)观察其肌支的分支情况;用卡尺对桡管(RT)、旋后肌管(ST)和桡侧腕短伸肌腱弓(AECRM)的形态和大小进行了观测,并对ST入口和出口的体表投影定位。结果ST入口和出口的宽度分别为(14.1±2.1)mm和(6.2±1.7)mm,长度为(35.0±6.9)mm。PIN从桡骨头至旋后肌腱弓(AF)和PIN从旋后肌穿出处的长度分别为(19.3±4.4)mm和(53.4±5.2)mm。AF的53.3%由肌性加腱性组织构成,23.3%由腱性组织构成,23.3%由肌组织构成。70%旋后肌远侧缘由腱性组织构成,所有AECRM均是腱性。桡骨背侧桡骨头下方1示指宽和3示指宽分别为ST的入口和出口的体表投影。结论本文提供的RT、ST和AECRM详细形态资料,对于PIN卡压的诊断和手术治疗具有指导意义。     

Effects of nerve compression or ischaemia on conduction properties of myelinated and non-myelinated nerve fibres. An experimental study in the rabbit common peroneal nerve

Compound action potentials of both myelinated (A) and non-myelinated (C) fibres in the common peroneal nerve of rabbits were studied during and after acute, graded compression of the nerve at 200 or 400 mmHg applied for 2 h or during ischaemia created by nitrogen inhalation or aortic occlusion. Compression of the nerve at 200 mmHg blocked the AI component (large myelinated fibres) after about 23 min, while compression at 400 mmHg shortened this time to 11 min. The A2 component (thinner myelinated fibres) had a lower conduction velocity and a higher resistance to compression. There was just a slight decrease in conduction velocity of the non-myelinated fibres when the nerves were compressed at 200 mmHg for 2 h. However, compression at 400 mmHg for 2 h induced a marked deterioration of amplitude and conduction velocity of the C-fibres. There was an incomplete restitution of function of A- and C-fibres during 2 h of recovery. The thinner myelinated fibres were more susceptible to deprivation of oxygen than the thicker ones, while non-myelinated fibres differed in response according to method of ischaemia induction. It is concluded that non-myelinated fibres are very resistant to compression and a very high pressure (greater than 400 mmHg) is needed to affect these fibres.     

Effects of nerve compression or ischaemia on conduction properties of myelinated and nonmyelinated nerve fibres. An experimental study in the rabbit common peroneal nerve

Compound action potentials of both myelinated (A) and non-myelinated (C) fibres in the common peroneal nerve of rabbits were studied during and after acute, graded compression of the nerve at 200 or 400 mmHg applied for 2 h or during ischaemia created by nitrogen inhalation or aortic occlusion. Compression of the nerve at 200 mmHg blocked the Ai component (large myelinated fibres) after about 23 min, while compression at 400 mmHg shortened this time to 11 min. The A2 component (thinner myelinated fibres) had a lower conduction velocity and a higher resistance to compression. There was just a slight decrease in conduction velocity of the nonmyelinated fibres when the nerves were compressed at 200 mmHg for 2 h. However, compression at 400 mmHg for 2 h induced a marked deterioration of amplitude and conduction velocity of the C-fibres. There was an incomplete restitution of function of A- and C-fibres during 2 h of recovery. The thinner myelinated fibres were more susceptible to deprivation of oxygen than the thicker ones, while non-myelinated fibres differed in response according to method of ischaemia induction. It is concluded that non-myelinated fibres are very resistant to compression and a very high pressure (> 400 mmHg) is needed to affect these fibres.     

腓总神经与腓骨颈的关系及其小腿各肌支的解剖学研究

目的明确腓总神经与腓骨颈的关系以及小腿各肌支的解剖学特征。方法取成人下肢标本40例,在肉眼及放大镜下解剖,观察腓总神经与腓骨颈的关系以及腓总神经各肌支的数目及走行,以腓骨头最突出点为测量起点,测量腓总神经绕腓骨颈处至腓骨头最突出点的距离;测量各肌支的发出点、入肌点的高度,并作统计学分析。结果腓总神经绕腓骨颈处至腓骨头最突出点的距离,左、右侧分别为(1.64±0.36)cm和(1.58±0.34)cm。各肌支的数目不等,其中胫骨前肌支数目最多,腓骨短肌支和跗长伸肌支的数目较少。40例标本中,腓总神经均穿行于腓骨颈部骨一筋膜管。结论腓总神经在绕腓骨颈处均穿行于骨一筋膜管。提示:这可能是导致腓总神经卡压综合征的主要原因之一;不同肌肉的神经肌支数目差别较大,与其所支配肌肉的结构、功能有关。     

Anatomical basis for a technique of ulnar nerve transposition

Summary There are five major anatomical locations where the ulnar nerve may be compressed near the elbow. Multiple sites of compression are often noted clinically; in other cases, the site of compression is difficult to identify. Clinical experience and results of a series of 20 anatomical dissections suggest that local decompression or subcutaneous transfer may be performed without necessarily exposing all five locations, posing a risk of incomplete decompression. Submuscular transfer of the ulnar nerve decompresses all five locations simultaneously and thus theoretically may be more reliable. The potentially superior results predicted by this anatomical investigation have been confirmed in a clinical case review. Submuscular transposition of the ulnar nerve is reliable and safe, not only in the primary treatment of ulnar neuropathy at the elbow but also in revision of previous operations. Presented at the Second Annual Meeting of the American Association of Clinical Anatomists, Omaha, June 7 to 8, 1985     

The significance of tibial and common peroneal nerves in nerve blocks

Purpose

The aim of this study was to elucidate the anatomical location of tibial nerve (TN) and common peroneal nerve (CPN) in the popliteal crease for specific nerve block.

Methods

Fifty fresh specimens from 27 adult Korean cadavers (16 males and 11 females, age 35–87 years) were investigated. Five of the 27 cadavers were used to determine the depths of nerves in cross-section.

Results

Tibial nerve was located 50 % from the most lateral point of the popliteal crease and 1.4-cm deep to the surface. In 20 % of the 50 specimens, the medial sural cutaneous nerve branched out below or at the popliteal crease, whereas the CPN was located at 26 % from the most lateral point of the popliteal crease and 0.7-cm deep from the surface. Furthermore, in 6 % of specimens the lateral sural cutaneous nerve branched out below or at the popliteal crease.

Conclusion

The results concerning the location of the TN and CPN at the popliteal crease offer a good guide to optimal nerve block.     

腓血管蒂腓骨嵌合组织瓣设计的解剖学基础

目的　为腓血管蒂腓骨嵌合组织瓣设计提供解剖学依据。 方法　用30侧成人下肢标本,以腓骨头和外踝为标志,将小腿分为上、中、下3区段解剖观测：①腓动脉起源、走行与分支;②腓动脉各区段肌（隔）穿支、骨膜支数目与分布。另1侧新鲜标本摹拟手术设计。  结果    腓动脉源于胫后动脉,移行为跟外侧动脉,中下段贴腓骨后面走行,沿途分支至邻近骨、肌肉和小腿外侧皮肤。其中：①腓骨骨膜支：（2~8）支、外径0.5~1.1 mm,分布腓骨中下1/3段骨膜：②胫骨骨膜支：（1~3）支、外径0.6~0.8 mm,营养胫骨中、下1/3段后面骨膜; ③肌（隔）穿支：（4~8）支、外径1.0~1.6 mm,支配小腿外侧中下段皮肤,并与胫前、胫后动脉皮支吻合。  结论　以腓动脉为蒂可设计腓骨嵌合组织瓣,依需要选择一种或多种嵌合组织瓣修复骨合并软组织缺损。     

Anatomical and histological basis of surgery to the radial nerve

Summary A study of the anatomical relationships of the radial nerve centered on those areas of greatest clinical interest, that is to say the spiral groove of the humerus and the radial canal of the elbow. The microscopical study based on serial histological sections from 7 specimens showed an immense variation in topography and in the number and diameter of nerve bundles in the different specimens. No particular endoneural fascicular organization was apparent to us from the studies. Emphasis is placed on the high percentage of connective tissue in relation to nervous tissue. All these factors together makes alignment of a sectioned nerve exceedingly difficult for the surgeon. Among other clinical applications of the study, the authors draw attention to the relationship of the radial nerve to disorders of the epicondyle.

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Bases anatomiques et histologiques dans la chirurgie du nerf radial

Résumé L'étude des rapports du nerf radial est centrée sur les régions d'intérêt clinique dans la gouttiére de torsion de l'humérus et dans le canal radial au coude. L'etude microsocipique par coupes histologiques sériées sur 7 spécimens fait apparaître une trés grande variabilité dans la topographie, le nombre et le diamétre de fascicules chez les différents spécimens. Aucune systématisation fasciculaire endoneurale ne nous est aaparue possible dans notre série. L'accent est mis sur le grand pourcentage du tissu conjonctif par rapport au tissu nerveux. Tous ces éleéments rendent difficile la réparation nerveuse aprés section. Parmi les applications cliniques, les auteurs insistent sur les relations entre le nerf radial et les épicondylalgies.

     

Branching patterns and localization of the common fibular (peroneal) nerve: an anatomical basis for planning safe surgical approaches

Purpose

Given the severity and incidence of injury to the common fibular (peroneal) nerve (CFN), there is a need to further clarify its anatomical location and branching patterns. This project attempts to consolidate current anatomical understanding of this nerve and provide physicians with reproducible measurements regarding the CFN and its branches.

Methods

Dissections were performed on 50 specimens (28 cadavers), both fresh and preserved. The CFN was dissected from its emergence from the fibular tunnel to its anterior tibial recurrent nerve (ATRN), superficial fibular nerve (SFN), and deep fibular nerve (DFN) branches. The CFN branching patterns were assessed and all variations were categorized into four types.

Results

Several significant relationships were identified between observable traits and key anatomical characteristics of the CFN. A significant correlation was found between fibular length and distance from the tip of the fibula to the DFN/ATRN branch, as well as between fibular length and distance from the tibial tuberosity to the SFN/DFN and DFN/ATRN branches. An association was identified between length of exposed sub-cutaneous CFN and height. Thickness of the biceps femoris tendon correlated significantly with BMI.

Conclusions

These findings allow physicians to better assess a patient’s individual CFN anatomy based on correlations with measureable physical traits and will contribute to anatomic education and successful completion of various surgical, anesthetic, and physical therapy procedures.     

Anatomical considerations of the deep peroneal nerve for biopsy of the proximal fibula in Thais

The present research aims to study the anatomical relationship between the deep peroneal nerve and the neighboring structures in the proximal fibula of Thais, with special regard to define the boundaries of a “safe” area when performing a biopsy of the proximal fibula. The proximal parts of 118 legs of 59 formalin‐embalmed adult cadavers (31 males, 28 females) were investigated. The distance from the apex of the fibular head to the point of origin of the deep peroneal nerve, the distance from the most lateral prominence of the fibular head to the anterior intermuscular septum, and the angle between the deep peroneal nerve and the fibula axis were measured. The results showed that the mean distances from the apex of the fibular head to the point of origin of the deep peroneal nerve was 28.4 ± 4.8 mm and from the most lateral prominence of the fibular head to the anterior intermuscular septum was 14.9 ± 2.0 mm. The mean angle between the deep peroneal nerve and the fibular axis was 28.1° ± 7.2°. In conclusion, these findings suggest that a “safe” area for bone biopsy in the proximal fibula of Thais is palpable anterior to the fibular head and downward laterally, not lower than 28 mm or 8% of the fibular length and from the most lateral prominence transverse medially not further than 14 mm. The inferior boundary of this area is an oblique line of the deep peroneal nerve about 28° from the fibular axis. Clin. Anat. 22:256–260, 2009. © 2008 Wiley‐Liss, Inc.     

膝部腓总神经和胫神经的弥散张量成像及临床应用

目的 为膝部腓总神经和胫神经病变的早期诊断提供新的影像学依据。方法 选取不同年龄段的膝关节弥散张量成像正常者60例和单侧格林-巴利综合征住院患者20例,在工作站划分腓总神经和胫神经不同部位的感兴趣区,测量各向异性分数(fractional anisotropy,FA)值和表观弥散系数(apparent diffusion coefficient,ADC)值,生成纤维示踪图像,加以比较分析。结果 膝部腓总神经和胫神经的左右侧、不同年龄段、不同部位的FA、ADC值均无统计学差异(P>0.05),合并处理得出腓总神经和胫神经的FA、ADC值分别为(0.65±0.05)、(1.04±0.12)×10^-3mm²/s和(0.63±0.04)、(1.09±0.13)×10^-3mm²/s。病变组膝部腓总神经和胫神经的FA、ADC值分别为(0.55±0.06)、1.26±0.19)×10^-3mm²/s和(0.50±0.07)、(1.36±0.18)×10^-3...     

Anatomical and clinical study of the common fibular nerve. Part 1: Anatomical study

The aims of this research were: (1) to minimize injury to the common fibular nerve by a detailed anatomical study of the nerve and its branches and (2) clinically to establish a protocol for preoperative and postoperative assessment of patients undergoing surgery on the proximal third of the leg. Thus the incidence of fibular nerve palsy would definitely be negligible. The first part of the research consisted of an anatomical study of the common fibular nerve and its branches, paying particular attention to the motor nerve branches innervating different muscles of the leg. Dissections were done on 20 unselected lower limbs of cadavers, of unknown gender, age and dominant side, to study the anatomy of the common fibular nerve and its branches and the neighboring structures, such as the tibia, the fibula and the muscles of the leg. It was found that 76.7% of all motor nerve branches were located in the proximal third of the leg, 19.5% in the middle third and 3.8% in the distal third. The free courses of the motor nerve branches were 48.5% in the proximal third, 44.4% in the middle third and 7.1% in the distal third. Within a distance of 6 cm from the fibular head we found 51.1% of the motor nerve branches and from 6 to 11 cm there were only 25.5%. Hence there were danger zones of high and low risk for injury to the common fibular nerve and its branches. Results obtained are evaluated and discussed with regard to safer surgical approaches and insertion of Steinmann pins in the proximal third of the leg.