Long head of the triceps branch transfer to axillary nerve in C5, C6 brachial plexus injuries: anterior approach

Shoulder abduction is a very complex movement and quite important for upper limb function, as more distal functions depend on a stable shoulder, especially in C5, C6 brachial plexus injuries. Various studies in the literature have emphasized the importance of improved functional outcome and shoulder reanimation with concomitant neurotization of suprascapular nerve and axillary nerve in C5, C6 brachial plexus injuries. A number of approaches to axillary nerve transfer in brachial plexus injuries have been reported. The author describes an innovative anterior deltopectoral approach for axillary nerve transfers in five patients with C5, C6 brachial plexus injuries. The spinal accessory nerve was neurotized with the suprascapular nerve through a transverse supraclavicular incision. The axillary nerve and the long head of the triceps branch were identified through the anterior deltopectoral approach and neurotized at the posterior cord level. This approach gives easy access to other donors such as the medial pectoral, thoracodorsal, and median and ulnar nerves. Oberlin's transfer was also performed for elbow flexion by extending the deltopectoral incision. The regained shoulder active abduction (M5) averaged 120 degrees and active external rotation averaged 65 degrees at the final follow-up of 26 months (average). This anterior deltopectoral approach is an excellent alternative for axillary nerve transfer in brachial plexus injuries and produces results comparable with those of other approaches. All brachial plexus surgeons must understand the anatomy and the relationship of the axillary nerve to the surrounding structures. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.     

Full-length phrenic nerve transfer by means of video-assisted thoracic surgery in treating brachial plexus avulsion injury

Phrenic nerve transfer has been widely used in treating brachial plexus avulsion injury. However, the present method crosses the thoracic part of the phrenic nerve, and nerve graft is needed, resulting in a long period of regeneration and partly irreversible muscle atrophy. We present our early experience of using video-assisted thoracic surgery to harvest a full length of phrenic nerve for transfer. Fifteen patients (mean age, 28 years) were treated. The thoracic part of the phrenic nerve was freed by means of video-assisted thoracic surgery and taken out of the thoracic cavity, and a full-length phrenic nerve was transferred to the musculocutaneous nerve to recover elbow flexion. The patients were followed. Another 29 patients with long-term follow-up who underwent traditional cervical phrenic nerve to musculocutaneous nerve transfer in our institute between 1994 and 1997 were selected. The period of newborn potential appearing in the biceps and the period for biceps to achieve M3 between two groups were compared. The operation was safe and no complications occurred. The additional length of phrenic nerve was 12.3 +/- 4.5 cm. Eleven patients received sufficient follow-up. Eight patients achieved biceps recovery to M3 (elbow flexion against gravity), and mean time was 198.8 +/- 36.0 days, much earlier than that of the traditional method (p < 0.01). Pulmonary function recovered to the preoperative level 9 months after operation. This new method is safe and minimally invasive. The result of full-length phrenic nerve transfer is much better than that of the traditional method. It obviously shortens the time required for nerve reinnervation, and offers a promising method for patients who have had a long interval from injury to operation and for forearm muscle reconstruction by phrenic nerve transferred to the median nerve or combined with free-muscle transfer.     

Validity of median nerve somatosensory evoked potentials in the diagnosis of supraclavicular brachial plexus lesions

Experience with median nerve SEPs in the diagnosis of brachial plexus lesions is analysed in 49 patients selected from a total material of 264 cases with brachial plexus problems tested by SEP techniques. Median nerve SEPs were always compared with the results of SEPs after stimulation of at least one other nerve relevant to the site of the lesion as suspected clinically and electromyographically. All patients presented with unilateral brachial plexus problems and all root lesions were verified by clinical presentation, EMG studies, myelogram or surgery. There were 19 brachial plexus injuries, 13 cases with cervical spondylopathic rediculopaties without myelopathy and 7 patients presented brachial plexopathy with systemic cancer. It was found that median nerve SEPs were always normal in injuries of upper trunk and root avulsions confined to one or two root levels. Median nerve SEPs were abnormal in multiple trunk lesions and multiple root avulsions. In patients with spondylopathic radiculopathies median nerve SEPs were normal apart from one case where involvement of multiple roots was present. Median nerve SEPs were useful in assessing patients presenting brachial plexus problems in the presence of systematic cancer apart from cases where lower trunk involvement was present.In general, median nerve SEPs are useful if they are combined with SEP testing of other nerves anatomically more closely related to the problem as outlined clinically and electromyographically.     

Response to comments on "Capnography as an aid in localizing the phrenic nerve in brachial plexus surgery. Technical note"

Comment on 'Capnography as an aid in localizing the phrenic nerve in brachial plexus surgery. Technical note' Bhagat H, Agarwal A, Sharma MS Journal of Brachial Plexus and Peripheral Nerve Injury 2008, 3:14 (22 May 2008)     

An overview of phrenic nerve and diaphragm muscle development in the perinatal rat.

In this overview, we outline what is known regarding the key developmental stages of phrenic nerve and diaphragm formation in perinatal rats. These developmental events include the following. Cervical axons emerge from the spinal cord during embryonic (E) day 11. At approximately E12.5, phrenic and brachial axons from the cervical segments merge at the brachial plexi. Subsequently, the two populations diverge as phrenic axons continue to grow ventrally toward the diaphragmatic primordium and brachial axons turn laterally to grow into the limb bud. A few pioneer axons extend ahead of the majority of the phrenic axonal population and migrate along a well-defined track toward the primordial diaphragm, which they reach by E13.5. The primordial diaphragmatic muscle arises from the pleuroperitoneal fold, a triangular protrusion of the body wall composed of the fusion of the primordial pleuroperitoneal and pleuropericardial tissues. The phrenic nerve initiates branching within the diaphragm at approximately E14, when myoblasts in the region of contact with the phrenic nerve begin to fuse and form distinct primary myotubes. As the nerve migrates through the various sectors of the diaphragm, myoblasts along the nerve's path begin to fuse and form additional myotubes. The phrenic nerve intramuscular branching and concomitant diaphragmatic myotube formation continue to progress up until E17, at which time the mature pattern of innervation and muscle architecture are approximated. E17 is also the time of the commencement of inspiratory drive transmission to phrenic motoneurons (PMNs) and the arrival of phrenic afferents to the motoneuron pool. During the period spanning from E17 to birth (gestation period of approximately 21 days), there is dramatic change in PMN morphology as the dendritic branching is rearranged into the rostrocaudal bundling characteristic of mature PMNs. This period is also a time of significant changes in PMN passive membrane properties, action-potential characteristics, and firing properties.     

The intercostal to phrenic nerve transfer: an effective means of reanimating the diaphragm in patients with high cervical spine injury

Nerve transfers have been well described for the treatment of congenital and traumatic injuries in the brachial plexus and extremities. This series is the first to describe nerve transfers to reanimate the diaphragm in patients confined to long-term positive pressure ventilation because of high cervical spine injury. Patients who have sustained injury to the spinal cord at the C3 to C5 level suffer axonal loss in the phrenic nerve. They can neither propagate a nerve stimulus nor respond to implanted diaphragmatic pacing devices (electrophrenic respiration). Ten nerve transfers were performed in six patients who met these conditions. The procedures used end-to-end anastomoses from the fourth intercostal to the phrenic nerve approximately 5 cm above the diaphragm. A phrenic nerve pacemaker was implanted as part of the procedure and was placed distal to the anastomosis. Each week, the pacemaker was activated to test for diaphragmatic response. Once diaphragm movement was documented, diaphragmatic pacing was instituted. Eight of the 10 transfers have had more than 3 months to allow for axonal regeneration. Of these, all eight achieved successful diaphragmatic pacing (100 percent). The average interval from surgery to diaphragm response to electrical stimulation was 9 months. All patients were able to tolerate diaphragmatic pacing as an alternative to positive pressure ventilation, as judged by end tidal CO2 values, tidal volumes, and patient comfort. Intercostal to phrenic nerve transfer with diaphragmatic pacing is a viable means of liberating patients with high cervical spine injury from long-term mechanical ventilation.     

Structure and homodynamia of the intersegmental connection TI-TII

The reason to consider the second thoracic cerebrospinal nerve (Th2) as one of the sources of the brachial plexus is the fact of the intersegmentary connection between Th1 and Th2 by means of a neural branch situating on the internal surface of the thorax near the vertebral column (the intrathoracic or paravertebral branch). However, not all cases of the intersegmentary connection Th1-Th2 should be regarded only as participation of Th2 in the formation of the brachial plexus, this is conditioned by certain peculiarities of its structure and by the character of interconnections with the I intercostal nerve. The macro-microscopic method demonstrates that the intersegmentary connection Th1-Th2 includes somatic and vegetative components, that to the same extent participate both in formation of the brachial plexus and in the I intercostal nerve. The intersegmentary connection Th1-Th2 is considered as a vegetative neural structure, containing somatic conductors and is considered as a homologue of superficial connective branches. It is the way, by which sympathetic fibers can reach the brachial plexus from the segment situating below, without passing through the superior thoracic nodes of the sympathetic trunk.     

Dynorphin-A (1-8) is contained within perikarya, nerve fibres and nerve terminals of rat duodenum

By the use of well-characterized antibodies against porcine dynorphin-A(1-8), an endogenous opioid peptide, and the use of a modified immunofluorescence microscopic technique, dynorphin-A(1-8) stained perikarya, nerve fibres, and nerve terminals were visualized in the rat duodenum. Dynorphin-A(1-8) immunoreactive perikarya were revealed with certainty only in the myenteric plexus, while dynorphinergic nerve fibres could bee seen in the myenteric plexus and circular muscle layer, but not in the longitudinal muscle layer and submucous plexus. Dynorphin-A(1-8) immunofluorescent nerve endings were in close contacts with submucosal blood vessels, probably arterioles, and Brunner's gland cells. These findings suggest that the opioid peptide dynorphin-A(1-8) might be synthetized within myenteric plexus perikarya of the rat duodenum and that it might modulate the peristaltic activity, intestinal blood pressure, and production of mucopeptides synthetized within Brunner's gland cells.     

Monoaminergic and cholinergic nerve fibres in the human dental pulp

Summary Distribution of cholinesterase-containing nerve fibres was studied in 15 human dental pulps by the thiocholine method. Falk's fluorescent method was used to demonstrate catecholamines (8 dental pulps).Cholinesterases were localized partly in the subodontoblastic plexus sending out fine branches towards odontoblasts, and partly in the nerve fibres attached to the blood vessel walls. These fibres in contrast to those of the subodontoblastic plexus were finer and showed fine varicosities.Monoaminergic terminals were localized mainly along blood vessel walls, however, some fibres having no relation to the blood vessels were also found.Cholinesterase-containing nerve fibres in the periphery of the pulp are considered to be sensitive nerve fibres originating from n.V. Distribution of cholinesterase-containing nerve fibres and monoaminergic terminals along the blood vessel walls indicates that the blood vessels in the human dental pulp might be under both parasympathetic and sympathetic control.     

Histochemistry and ultrastructure of nerve fibres and contractile cells in the tunica albuginea of the rat testis

Whole-mounted preparations of the tunica albuginea of the rat testis were studied using light microscopy techniques for demonstration of cholinergic nerve fibres (Karnovski-Root method), catecholaminergic nerve fibres (De la Torre's method) and actin filaments (avidin-biotin-peroxidase method). An ultrastructural study of different regions of the albuginea was also performed. Cholinergic fibres were seen to penetrate into the albuginea with the testicular artery to form a broad network in the mediastinum testis, many fibres ending beneath the rete testis epithelium. Catecholaminergic fibres penetrated through the middle part of the cauda epididymis and formed a plexus in the albuginea covering the inferior testicular pole. This plexus gave rise to straight fibres which formed varicosities, some of them appeared related with mast cells. Actin-containing cells were only found beneath the rete testis epithelium. These cells were similar to myofibroblasts. The location of both cholinergic fibres and contractile cells among the rete testis channels suggests that these cells may be involved in the pumping of semen towards the ductuli efferentes and that their contractility may be regulated by cholinergic fibres.     

Restoration of elbow flexion after brachial plexus injury: the role of nerve and muscle transfers

Brachial plexus trauma results in a variable loss of upper extremity function. The restoration of this function requires elbow flexion of adequate strength and range of motion. A proper evaluation of brachial plexus lesions is a prerequisite to any reconstructive procedure, and appropriate guidelines are presented. One option for restoring elbow flexion is a nerve transfer. The best results with this procedure are obtained in young patients treated within 6 months of injury. Another option is a free or pedicled muscle transfer, which should be considered in older patients or patients treated more than 6 months after an injury. Muscle transfers may also be used to augment the results of nerve transfer procedures. Choices and clinical results of donor nerves and muscle for transfer are discussed, and an algorithm for treatment is presented.     

Avian enteric nerve plexuses

Summary The enteric nerve plexuses of the domestic fowl (Gallus domesticus) were investigated in sections and stretch preparations by means of the cholinesterase and glyoxylic acid fluorescence histochemical techniques. Cholinesterase-positive and varicose and non-varicose fluorescent nerve fibres were distributed at all levels of the gut in myenteric, submucosal, muscle and mucosal plexuses, and in a perivascular plexus. The density of the innervation and the detailed distribution of the nerves varied in different parts of the intestinal tract. All nerve plexuses appeared to be best developed in the rectum. Whereas the circular muscle coat contained a substantial number of nerves at all levels of the gut, the longitudinal coat was well innervated only in the rectum. The major portion of the mucosal plexus appeared to be associated with the intestinal glands. The nerve cell bodies were restricted to the myenteric and submucosal plexuses and were mainly cholinesterase-positive. Fluorescent ganglion cells were not observed. Pretreatment of stretch preparations with NADH: Nitro BT to stain ganglion cells showed that the majority of the cells were surrounded by a meshwork of fluorescent varicose fibres, although none of the fibres appeared to be associated with individual cells. The perivascular plexus was mainly associated with the arteries. The functional significance of the innervation is discussed.We would like to thank the British Council for financial support for Mr. H.A. Ali     

Anatomy of the spinal accessory nerve plexus: relevance to head and neck cancer and atherosclerosis

The term spinal accessory nerve plexus may be defined as the spinal accessory nerve with all its intra- and extracranial connections to other nerves, principally cranial, cervical, and sympathetic. The term is not new. This review examines its applied anatomy in head and neck cancer and atherosclerosis. Over the centuries, general studies of neural and vascular anatomy and embryology formed a basis for the understanding upon which the plexus is described. During the past century, its anatomy and blood supply have come to be better understood. The importance of almost all of the plexus to head, neck, and upper extremity motor and sensory functions has come to be realized. Because of this understanding, surgical neck dissection has become progressively more conservative. This historical progression is traced. Even the most recent anatomic studies of the spinal accessory nerve plexus reveal configurations, new to many of us. They were probably known to classical anatomists, and not recorded in readily available literature, or not recorded at all. Human and comparative anatomic studies indicate that the composition of this plexus and its blood supply vary widely, even though within the same species their overall function is very nearly the same. Loss of any of these structures, then, may have very different consequences in different individuals. As a corollary to this statement, data are presented that the spinal accessory nerve itself need not be cut during surgical neck dissections for severe impairment to occur. In addition, data are presented supporting the theory that atherosclerosis by obstructing vessels to this plexus and its closely connected brachial plexus will very likely result in their ischemic dysfunction, often painful. Finally evidence, as well as theory, is stated concerning anatomic issues, methodology, outcome, and possible improvements in surgical procedures emphasizing conservatism.     

The distribution and origin of calcitonin gene-related peptide-containing nerve fibres in feline dental pulp. Relationship with substance P-containing nerve fibres

The origin and distribution of calcitonin gene-related peptide (CGRP)-like immunoreactivity in feline dental pulp were studied using indirect immunofluorescence. Nerve fibres with varicosities exhibiting CGRP-like immunoreactivity were observed to enter the pulp with blood vessels. Many CGRP-containing nerve fibres were found to extend along blood vessels in the central pulp, and some of these fibres exhibited a network arrangement in the walls of dental pulp blood vessels. However, some of fibres were apparently not associated with blood vessels. Some thin, CGRP-containing nerve fibres formed a part of the nerve plexus in the subodontoblastic area and penetrated into the odontoblastic layer. In animals that had undergone transection of the inferior alveolar nerve, no CGRP-containing nerve fibres were observed. Application of a double-immunofluorescence staining technique also revealed that the distribution of CGRP-containing nerve fibres is very similar to that of substance P-containing nerve fibres.     

树鼩(Tupaia belangeri chinensis)的脊神经丛

由于树鼩在系统发育方面所具的特殊性,以及当今实验动物的小型化趋向,树鼩正在被开发成为新型的实验动物,其生物学特性的研究随之蓬勃开展,如对染色体(陈宜峰等,1981)、神经生理(刘世熠等,1982)、血象(邹如金等,1983)、骨髓象(张耀平等,1986)、血液生化(彭燕章等,1986;陈保生等,1983)、皮纹(Haines,1955;张耀平等,1984)、解剖(Le Gros Clark,1924、1926;George,1977)、     

Funnel web spider venom produces spontaneous action potentials in nerve

Venom from the lethal Australian spider, $\text{Atrax robustus}$, causes fasciculation of muscles $\text{in vivo}$ and in isolated diaphragms in mice. Spontaneous end-plate potentials were recorded in muscle fibres exposed to the venom and associated spontaneous electrical activity could also be recorded from the phrenic nerve. It was proposed that the venom produces muscle fasciculation by causing abnormal, spontaneous, repetitive firing of motor nerves. The mechanism of this action was investigated in aplysia neurones. The venom produced abnormal, spontaneous, repetitive inward currents in voltage clamped neurones and changed the current-voltage characteristics of the surface membrane. It is suggested that the basic mode of action of Funnel-web venom is to change the electrical field in nerve membrane.     

The projections of chemically identified nerve fibres in canine ileum

Summary The projections of nerve fibres with immunoreactivity for the peptides enkephalin (ENK), gastrin-releasing peptide (GRP), neuropeptide Y (NPY), somatostatin (SOM), substance P (SP) and vasoactive intestinal peptide (VIP) were studied in canine small intestine by analysing the consequences of lesions of intrinsic and extrinsic nerves. Of peptides present in fibres supplying myenteric ganglia, GRP, SOM and VIP were in anally directed nerve pathways, whereas ENK and NPY were in orally directed pathways. Pathways ran for up to about 30 mm. SP fibres ran for short distances in both directions in the myenteric plexus. The circular muscle was supplied with ENK, NPY, SP and VIP fibres arising from the myenteric ganglia, whereas most mucosal SP and VIP fibres were deduced to arise from submucous ganglia. There were projections of fibres reactive for ENK, GRP, SOM, SP and VIP from myenteric ganglia to submucous ganglia. Antibodies to tyrosine hydroxylase were used to locate noradrenaline nerve fibres supplying the intestine; these fibres all disappeared when extrinsic nerves running through the mesentery to the small intestine were cut. It is deduced that there is an ordered pattern of projections of peptide-containing fibres in the canine intestine.     

l-Theanine and NEP1-40 promote nerve regeneration and functional recovery after brachial plexus root avulsion

Brachial plexus root avulsion causes severe sequelae Treatments and prognosis face many problems, including inflammatory reaction, oxidative damage, and myelin related inhibitory effect. l-Theanine has anti-inflammatory, anti-oxidative, and neuroprotective effects. NEP1-40 competitively inhibits Nogo-66 receptor (NgR1) promotes axonal regeneration. Forty-eight Sprague-Dawley rats were randomly assigned into four groups to establish an animal model of brachial plexus root avulsion. Inflammation and oxidative damage were evaluated by spectrophotometry and motor function of the upper limbs was assessed via Terzis grooming test after modeling. Immunofluorescence and hematoxylin and eosin staining were utilized to determine the content of reactive oxygen species, activation of microglial cells, neuroprotection, and nerve regeneration. Compared with the control group, the L-Theanine + NEP1-40 group had significantly decreased myeloperoxidase, malondialdehyde, interleukin-6, reactive oxygen species, and microglial cells, significantly increased score on the Terzis grooming test, increased motor neuron content, and thickened muscle fibers, increased area, and appearance of large and clear motor endplate structures. The results of this study suggest that l-Theanine combined with NEP1-40significantly promoted nerve regeneration after brachial plexus root avulsion, and may be a potential treatment for promoting nerve regeneration. Possible mechanisms underlying these results are alleviation of oxidative damage and inflammatory responses in the injured area and antagonism of myelin inhibition.     

Corticotropin-releasing factor is contained within perikarya and nerve fibres of rat duodenum

Immunofluorescence microscopic studies revealed a corticotropin-releasing factor (CRF) staining within both myenteric plexus perikarya and nerve fibres of the rat duodenum. A CRF-immunofluorescence could be visualized also within nerve fibres close associated with myenteric and submucous blood vessels. Even the lamina propria contained CRF-immunoreactive nerve fibres, which were obviously often localized near the basal lamina.     

Altered breathing pattern elicited by stimulation of abdominal visceral afferents

The effect of stimulation of afferent mesenteric nerves on tidal volume (VT), phrenic nerve, and external intercostal muscle activities was studied in anesthetized spontaneously breathing cats. Both mechanical distension of the small intestine and electrical stimulation of the mesenteric nerves resulted in an initial inspiratory inhibition of VT followed by a gradual recovery above the prestimulus controls. Changes in VT were accompanied by a depression of phrenic nerve activity and an excitation of external intercostal muscle activity. During the recovery phase of VT, the amplitude of phrenic nerve activity returned only partially, whereas the activity of the external intercostal muscle was greater than the prestimulus controls. In a second group of experiments, brief tetanic stimulation at the beginning of inspiration led to a complete and maintained inhibition of phrenic nerve activity but with a simultaneous excitation of external intercostal muscle activity and without any change in VT; whereas expiratory stimulation caused a decrease in expiratory abdominal muscle activity, without changing the peak amplitude of phrenic nerve activity. The respiratory changes observed with distension of the small intestine were abolished after denervation of the mesenteric plexus. It is concluded that activation of the visceral afferents of the mesenteric region reflexly changes diaphragmatic breathing to intercostal breathing. It is assumed that such a type of breathing pattern may occur in pregnancy and in pathophysiological situations involving splanchnic viscera.