An alternative method for restoring opposition after median nerve injury: an anatomical feasibility study for the use of neurotisation

Opposition, one of the most important functions of the hand, is lost or impaired after median nerve injury. Complete recovery does not always occur after treatment, and various techniques of opponensplasty are used for restoring opposition. This study was performed in order to develop an alternative method for selective restoration of thenar muscle function. Ten arms from 5 cadavers were used. The median nerve with its thenar motor branch (Tb) and the anterior interosseous nerve with its motor branch to pronator quadratus (PQb) were prepared in the distal forearm. The mean widths and the number of myelinated fibres of these nerves were: PQb 1.3±0.10 mm, Tb 1.4±0.12 mm and PQb 912±88 mm, Tb 1020±93 mm. The minimum necessary distance from the distal flexor crease of the wrist for neurotisation of the Tb by the PQb was 60±5.41 mm. It was concluded that PQb‐Tb neurotisation would be possible anatomically. The advantages are that motor function is reestablished with a motor nerve, the diameters and the number of myelinated fibres of both nerves are similar, the loss of function after denervation of the pronator quadratus is slight and opponensplasty still remains as a final option.     

The possibility of deep peroneal nerve neurotisation by the superficial peroneal nerve: an anatomical approach

Neurotisation involves transfer of nerves for the restoration of function following injury. A number of nerves have been used in different part of the peripheral nervous system. This study was undertaken to develop a practical and relatively safe surgical approach to the treatment of L4 root lesion's. We examined the effectiveness and safety of neurotisation of the deep peroneal nerve and its branches by the superficial peroneal nerve. Twelve legs of dissected cadavers provided for teaching purposes in the anatomy laboratory were used to display the common peroneal nerve and its branches. Each branch was measured using calipers and analysed to investigate the possibility of neurotisation of the deep peroneal nerve by the superficial peroneal nerve and its branches. It was found that of the measured branches, transposition was possible between those to peroneus longus and tibialis anterior on the basis of their diameter and length. In recent decades, advances in microsurgical reconstruction and understanding of the microanatomy have played major roles in improving the results of surgical treatment of nerve injuries. There is a need for further experimental studies on the feasibility of this surgical approach.     

Anatomical basis of neurotisation of the median nerve in the hand by the radial nerve

Summary The sensory sequelae after lesions of the median nerve cause difficulties in treatment since few sensory transfers are available. Neurotisation of the median by sensory branches of the radial nerve have aroused little interest although they have already been used by some authors after anastomosis at the wrist or through the first or second interosseous spaces. Based on what was originally a purely anatomic study, our interest was directed to the possibilities of performing more distal neurotisation for the treatment of sensory disorders of limited extent. The chief object was to obtain faster sensory reinnervation. 30 hands were dissected and a radial branch was defined as suitable for neurotisation whose diameter approximated that of its palmar digital homolog. Only those findings constantly observed in analysis of the hands studied were taken into account. It is therefore possible to reliably define the type and site of the routes of approach as well as the sensory branches suitable for neurotisation.

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Bases anatomiques de la neurotisation du nerf médian à la main par le nerf radial

Résumé Les séquelles sensitives après lésion du nerf médian posent un problème thérapeutique car peu de transferts sensitifs sont disponibles. La neurotisation du médian par les branches sensitives du radial suscite peu d'intérêt bien que déjà utilisée par quelques auteurs après anastomose au poignet ou à travers le ler ou 2ème espace inter-osseux. A partir d'un travail uniquement anatomique, notre intérêt s'est porté sur les possibilités effectives de neurotisations plus distales pour le traitement de troubles sensitifs limités dans leur topographie. L'intéret étant surtout d'obtenir une réinnervation sensitive plus rapide. 30 mains ont ainsi été disséquées. Nous avons défini comme neurotisable un rameau radial dont le diamètre était voisin de son homologue digital palmaire. Seules ont été prises en compte les données constantes retrouvées après l'analyse des mains étudiées. Il est ainsi possible de définir de manière fiable le type et le siège des voies d'abord ainsi que les rameaux sensitifs utilisables pour la neurotisation.

     

肘部及前臂上段正中神经卡压综合征的临床解剖学研究

目的 探讨肘部正中神经卡压综合征的解剖学基础。方法 解剖观察５０侧上肢标本,结果 肱二头肌腱膜与正中神经的关系有非覆盖４０例（８０％）,部分覆盖型６侧（１２％）和完全覆盖型４侧（８％）。旋前圆肌纤维桥斜过正中神经前方３２侧（６４％）。旋前圆肌肱骨头肌内有腱束８例（成人,占１８．６％）,尺骨头汪岙较厚筋膜４７侧（９４％）。指浅屈肌起始结构有联合腱弓型４４侧（８８％）,纤维情怀２侧型（４％）和腱束型（     

用旋前方肌肌桥修复正中神经缺损的应用解剖

在30侧成人上肢标本上,观测了旋前方肌的形态和血供.旋前方肌血供来自骨间前动脉、桡动脉和尺动脉的旋前方肌肌支.肌的血供主要来自骨间前动脉,以骨间前血管为蒂,依据神经损伤平面的不同,可设计以旋前方肌上、中、下不同部位的肌桥为桥接体、     

骨间前神经转位重建鱼际肌功能

前臂或腕部正中神经断裂,直接吻合后鱼际肌功能的恢复常常令人失望,为了解决这一难题,本文在120侧成人上肢解剖学研究的基础上,采用骨间前神经转位术修复鱼际肌支9侧,获得成功.     

胫神经近端肌支移位治疗高位坐骨神经损伤的应用解剖

目的：探讨胫神经的近端肌支移位治疗某些高位坐骨神经损伤的解剖学可行性。方法选取15具（30侧）福尔马林固定的成人下肢标本,解剖并测量胫神经近端各肌支的长度、直径、发出点至腓骨小头平面的距离（位置）和至腓骨颈的距离;从分叉部向近端膜内分离腓总神经的腓深腓浅两部分,测量可分离的最大长度以及腓深神经的直径。结果胫神经近端主要肌支有比目鱼肌支、腓肠肌外侧头支和腓肠肌内侧头支,其长度分别为(53.2±9.9)、(36.3±9.6)、(44.7±8.6) mm;从分叉部向近端膜内分离腓总神经的最大长度为(59.3±7.2) mm;分离后,所有标本的比目鱼肌支和腓肠肌外侧头支以及28侧（占93.3%）标本的腓肠肌内侧头可直接与腓深神经无张力地吻合。结论膜内分离腓总神经后,近端胫神经肌支移位移位治疗高位坐骨神经损伤在解剖学上可行。综合考虑各肌支的长度和直径,比目鱼肌支是移位的最佳供体神经。     

Bilateral variant contributions in the formation of median nerve

Bilateral variations in the formation of median nerve (Mn) and the recurrent course of its communications with musculocutaneous nerve (MCn) are very rare. These bilateral anomalies were observed during a routine dissection of the upper limbs of an adult male cadaver in the Department of Anatomy, PGIMER, Chandigarh. On both the sides, Mn was formed by the union of three roots. There was an additional lateral root on both sides. On the right side it was a contribution from the lateral cord and on the left it arose from the anterior division of the middle trunk. On the left side the lateral cord was formed distal than usual in relation to the second part of the axillary artery. On the right side a communicating branch arising from the additional lateral root followed a recurrent course and divided into two to unite separately with medial root of median, while on the left side a single communicating branch from an additional lateral root united with the medial root of median. Recurrent course of the communicating branch between lateral root of median and medial root of median has not been reported earlier. On the right side the MCn after piercing the coracobrachialis gave another communicating branch, which joined the Mn at the level of insertion of deltoid.     

Relationships of the palmar cutaneous branch of the median nerve: a morphometric study

Treatment of carpal tunnel syndrome consists in decompression of the median nerve by section of the flexor retinaculum. Usually, this surgery improves the disease with disappearance of the symptoms. However, some painful sequelae may remain such as painful discharges, paresthesiae or permanent anesthesia of the base of the thumb or of the scar related to an injury of the palmar cutaneous branch of the median nerve (PCBm). This study was performed to define the accurate emergence and the anatomic characteristics of this nerve in relation to stable landmarks. Moreover, it assessed the importance of the visual identification of the branch during section of the flexor retinaculum. Thirty-five hands were dissected under macroscopic examination and under magnification of the thinnest branches. Measurements were performed with a caliper and the forearm in supination. Determination of the bistyloid line showed variability in the location of the distal wrist crease. Thus, it could not be used as a landmark to locate the PCBm. The palmar cutaneous branch is the distal collateral branch of the median nerve in the forearm. It emerges on its radial side, on average 44.3 mm before the bistyloid line. It courses in line with the third finger and perforates the antebrachial aponeurosis about 5.7 mm from the bistyloid line. This emergence can be located in the palm, where it can be injured if the incision is performed in line with the third finger. The PCBm usually ends in the palm by division into two or three branches. The lateral branch supplies the skin of the thenar eminence while the medial, usually shorter branch supplies the midline part of the palm. This study has shown the importance of performing the cutaneous incision in line with the fourth finger to avoid injury to the PCBm.     

An anatomical study of porcine peripheral nerve and its potential use in nerve tissue engineering

Current nerve tissue engineering applications are adopting xenogeneic nerve tissue as potential nerve grafts to help aid nerve regeneration. However, there is little literature that describes the exact location, anatomy and physiology of these nerves to highlight their potential as a donor graft. The aim of this study was to identify and characterise the structural and extracellular matrix (ECM) components of porcine peripheral nerves in the hind leg. Methods included the dissection of porcine nerves, localisation, characterisation and quantification of the ECM components and identification of nerve cells. Results showed a noticeable variance between porcine and rat nerve (a commonly studied species) in terms of fascicle number. The study also revealed that when porcine peripheral nerves branch, a decrease in fascicle number and size was evident. Porcine ECM and nerve fascicles were found to be predominately comprised of collagen together with glycosaminoglycans, laminin and fibronectin. Immunolabelling for nerve growth factor receptor p75 also revealed the localisation of Schwann cells around and inside the fascicles. In conclusion, it is shown that porcine peripheral nerves possess a microstructure similar to that found in rat, and is not dissimilar to human. This finding could extend to the suggestion that due to the similarities in anatomy to human nerve, porcine nerves may have utility as a nerve graft providing guidance and support to regenerating axons.     

尺神经深支的应用解剖

目的:为尺神经深支卡压和损伤的临床诊治以及高位尺神经损伤直接移植修复尺神经深支提供解剖学依据.方法:选择30侧自肘以上离断新鲜完整无畸形上肢进行解剖,观察尺神经深支的走行和分支.测量小鱼际各肌支的长度、宽度和厚度;尺神经深支相邻肌支间距离;豌豆骨近缘至深支最末分支间长度;尺神经深支逆向可分离长度和分离后的近端宽度和厚度,骨间前神经旋前方肌支远端宽度和厚度.结果:尺神经深支分支复杂,呈树枝状结构,在其走行过程中经Guyon管、豆钩管、对掌肌管、拇收肌腱弓等,解剖关系复杂.相应骨间肌支和蚓状肌支大部在尺神经深支主干同一平面呈不同角度发出.结论:尺神经深支易卡压部位多,可能是高位尺神经损伤后手内在肌功能不易恢复的原因之一;邻近骨折脱位较易损伤尺神经深支;高位尺神经损伤早期行神经移位直接修复尺神经深支,有利于手功能的恢复.     

An applied anatomical study of the superior laryngeal nerve loop

The aim of this study was to provide some specific information about the morphology and topography of the superior laryngeal n., its branches, and its anastomoses with the cervical sympathetic chain, as well as its relations with the thyroid gland. Sixty adult cadavers, ie 120 superior laryngeal nn., were dissected and analysed. An anastomotic loop connecting the cervical sympathetic chain and the distal laryngeal n. was present in 111 of the 120 cases. The morphology of this loop made it possible to define 5 different groups. This study supplies information valuable in thyroid surgery.     

An anatomical study of the palmar cutaneous branch of the median nerve

We present an anatomical study of the palmar cutaneous branch of the median nerve emphasizing its frequency, origin, perforation point at the transverse carpal ligament, point of emergence in the palm, width, length, divisions and innervation territory. For this purpose, fifty cadaver hands were dissected under a stereomicroscope and/or magnifying glass. The origin of the palmar cutaneous branch (PCB) was on the average 4.56 cm proximal to conventionally named "zero point" on the most distal transverse volar wrist crease. Perforation of the aponeurosis occurred on average 0.79 cm from the mentioned point and its emergence in the palm at 0.76 cm. The nerve had an average length of 5.24 cm. PCB's divisions in the palm resulted in a medial branch in 42%, a lateral branch in 92% and an intermediate branch in 100% of the hands studied. In six specimens PCB presented a deep branch which was directed toward the thenar eminence or made communication with the superficial branch of the palmar digital nerve or still penetrated between the first or second metacarpal. In 4% of the cases there was a communicating branch between the superficial branch of the radial nerve and the PCB. These anatomical results should be considered in the evaluation of the best surgical techniques for decompression of the median nerve in the carpal tunnel.     

Cutaneous innervation of the ankle: An anatomical study showing danger zones for ankle surgery

Three nerves innervate the skin in the foot and ankle region: the saphenous, sural, and superficial peroneal nerves. Because they are close to the medial and lateral malleoli, these nerves are at significant risk during orthopedic interventions. The aims of this study were to investigate the distal courses of the three cutaneous nerves of the ankle and to determine their exact relationships with easily identifiable bony landmarks. Ten freshly frozen and 40 embalmed lower extremities of adults were dissected. The positions of the superficial peroneal, sural, and saphenous nerves were determined using reference lines based on easily palpable osseous landmarks. The frequencies and distributions of all three nerves and their branches were converted into absolute numbers. A danger zone for each nerve was established on the basis of the distribution of crossings between the nerves and the different reference lines. Determination of the exact orientation of the nerves around the ankle should help minimize the nerve injury rate during surgical approaches in this area. Using this easily translatable new grid system, the course and danger zones of each cutaneous nerve around the ankle can be estimated clinically. Clin. Anat. 653–658, 2014. © 2013 Wiley Periodicals, Inc.     

桡神经肱肌支的解剖学研究

目的：研究桡神经的肱肌支的形态特点。方法：对７２侧固定尸体的桡神经肱肌支进行解剖与测量，并分为三种不同的类型进行比较。结果：桡神经存在肱肌支出现率为５１．４％（３７侧）。肱肌支的出现以单侧多见，与性别、侧别无关。对肱肌支的起始点、入肌点、长度及横径测量结果，将其归分为：上升型、下降型和水平型三种类型。肌支的起始点在Ｈｕｅｔｅｒ＇ｓ线上３．０～９．６ｃｍ，入肌点在Ｈｕｅｔｅｒ＇ｓ线下０．２～线上９．５ｃｍ，肌支长度０．７～９．６ｃｍ，横径为０．４～２．０ｍｍ。结论：桡神经的肱肌支较普遍存在，行上臂、肘部手术时，应对其加以保护，尤其是在肌皮神经已有损伤者更应如此     

骨间后神经穿桡管远端处的解剖特点及其临床意义

目的：了解骨间后神经穿旋后肌后可能的卡压位置及临床意义,方法：在2倍放大镜下解剖骨间后神经穿旋后肌后的行程,分支,可能卡压位置以及前臂活动对其影响。结果：骨间后神经穿旋后肌后恒定地分尺仙支和桡侧支;旋后肌远侧缘和拇短伸肌,拇长展肌浅面的腱性肌纤维结构可能是致卡压的解剖结构,前臂伸肌群的活动可 诱发上述结构卡压骨间后神经,结论：在桡管远端同样存在卡坟骨间后神经的解剖结构,必要时应手术探查,松解。     

Ultrasonography-guided anterior approach for axillary nerve blockade: An anatomical study

Combined ultrasound (US)-guided blockade of the suprascapular and axillary nerves (ANs) has been proposed as an alternative to interscalene blockade for pain control in shoulder joint pathology or postsurgical care. This technique could help avoid respiratory complications and/or almost total upper limb palsy. Nowadays, the AN blockade is mostly performed using an in-plane caudal-to-cephalic approach from the posterior surface of the shoulder, reaching the nerve immediately after it exits the neurovascular quadrangular space (part of the spatium axillare). Despite precluding most respiratory complications, this approach has not made postsurgical pain relief any better than an interscalene blockade, probably because articular branches of the AN are not blocked.Cephalic-to-caudal methylene blue injections were placed in the first segment of the AN of six Thiel-embalmed cadavers using an US-guided anterior approach in order to compare the distribution with that produced by a posterior approach to the contralateral AN in the same cadaver. Another 21 formalin-fixed cadavers were bilaterally dissected to identify the articular branches of the AN.We found a good spread of the dye on the AN and a constant relationship of this nerve with the subscapularis muscle. The dye reached the musculocutaneous nerve, which also contributes to shoulder joint innervation. We describe the anatomical landmarks for an ultrasonography-guided anterior AN blockade and hypothesize that this anterior approach will provide better pain control than the posterior approach owing to complete blocking of the joint nerve. Clin. Anat. 33:488–499, 2020. © 2019 Wiley Periodicals, Inc.     

Stretch-induced nerve injury: a proposed technique for the study of nerve regeneration and evaluation of the influence of gabapentin on this model

The rat models currently employed for studies of nerve regeneration present distinct disadvantages. We propose a new technique of stretch-induced nerve injury, used here to evaluate the influence of gabapentin (GBP) on nerve regeneration. Male Wistar rats (300 g; n=36) underwent surgery and exposure of the median nerve in the right forelimbs, either with or without nerve injury. The technique was performed using distal and proximal clamps separated by a distance of 2 cm and a sliding distance of 3 mm. The nerve was compressed and stretched for 5 s until the bands of Fontana disappeared. The animals were evaluated in relation to functional, biochemical and histological parameters. Stretching of the median nerve led to complete loss of motor function up to 12 days after the lesion (P<0.001), compared to non-injured nerves, as assessed in the grasping test. Grasping force in the nerve-injured animals did not return to control values up to 30 days after surgery (P<0.05). Nerve injury also caused an increase in the time of sensory recovery, as well as in the electrical and mechanical stimulation tests. Treatment of the animals with GBP promoted an improvement in the morphometric analysis of median nerve cross-sections compared with the operated vehicle group, as observed in the area of myelinated fibers or connective tissue (P<0.001), in the density of myelinated fibers/mm² (P<0.05) and in the degeneration fragments (P<0.01). Stretch-induced nerve injury seems to be a simple and relevant model for evaluating nerve regeneration.     

Functional anatomy of the mandibular nerve: consequences of nerve injury and entrapment

Various anatomic structures including bone, muscle, or fibrous bands may entrap and potentially compress branches of the mandibular nerve (MN). The infratemporal fossa is a common location for MN compression and one of the most difficult regions of the skull to access surgically. Other potential sites for entrapment of the MN and its branches include, a totally or partially ossified pterygospinous or pterygoalar ligament, a large lamina of the lateral plate of the pterygoid process, the medial fibers of the lower belly of the lateral pterygoid muscle and the inner fibers of the medial pterygoid muscle. The clinical consequences of MN entrapment are dependent upon which branches are compressed. Compression of the MN motor branches can lead to paresis or weakness in the innervated muscles, whereas compression of the sensory branches can provoke neuralgia or paresthesia. Compression of one of the major branches of the MN, the lingual nerve (LN), is associated with numbness, hypoesthesia, or even anesthesia of the tongue, loss of taste in the anterior two thirds of the tongue, anesthesia of the lingual gums, pain, and speech articulation disorders. The aim of this article is to review, the anatomy of the MN and its major branches with relation to their vulnerability to entrapment. Because the LN expresses an increased vulnerability to entrapment neuropathies as a result of its anatomical location, frequent variations, as well as from irregular osseous, fibrous, or muscular irregularities in the region of the infratemporal fossa, particular emphasis is placed on the LN.     

高频超声对正常正中神经显像及其临床意义

目的 通过高频超声探查上肢正中神经全程并熟练掌握正中神经的超声探查手法,选取超声易于辨识的解剖位点测量正中神经的横截面积（CSA）并探讨其与周围组织的关系,提供正常参考值范围并为临床诊断外周神经疾病提供依据。 方法 对240例健康志愿者沿正中神经走行进行高频超声探查,依次测量5个位点 ［腕管（腕横纹处）、前臂中点、正中神经穿出旋前圆肌处、肱骨髁上处及肱骨中点处］的CSA,每个位点重复测量３次取其均值,并进行CSA与身高、体重的相关性分析。 结果 高频超声显示,正常人正中神经横截面呈筛网状低回声图像,在不同部位分别显示为圆形、椭圆形或三角形,纵截面上成束状平行排列的低回声被断续的条带状高回声分割。探查得出,正中神经在上述5个位点的CSA均值以及双侧上肢之间同一位点处正中神经的CSA差异无统计学意义。 结论 正中神经在高频超声下全程可探及,显示率为100％;在不同部位的正常值及超声声像图略有差异,差异有统计学意义;正中神经的CSA在上臂段最粗,腕管处次之,前臂段最细。