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Medial Branch (medial + branch)
Selected AbstractsNeural plasticity of neonatal hypoglossal nerve for effective sucklingJOURNAL OF NEUROSCIENCE RESEARCH, Issue 11 2007Nanae Fukushima Abstract The adaptive movement of the tongue after unilateral lesion of the hypoglossal (XII) nerve during the early postnatal days is essential for recovery of milk intake. The present study investigated the basic mechanisms underlying such adaptation, focusing on the neural plasticity that allows effective suckling. After resection of the ipsilateral XII nerve on P1, 1,1,-dioctadecyl-3,3,3,,3,-tetramethylindocarbocyanine perchlolate (DiI), a postmortem neuronal tracer, was applied to the contralateral uninjured XII nerve on P4 and P7. DiI-labeled fibers were traced successfully within the tongue and showed gradually increased extension over the XII nerve-injured side in the central core portion of the denervated tongue between P4 and P7. Systematic neuroanatomic experiments showed that contralateral axonal sprouting occurred as early as 1 day after nerve injury (P2), and that such axonal sprouting occurred exclusively from the medial branch of the XII nerve responsible for tongue protrusion, an essential movement for suckling. These findings provide direct evidence of functional neural plasticity that allows effective suckling in XII nerve-injured newborns with suckling disturbance. © 2007 Wiley-Liss, Inc. [source] Radiofrequency Neurotomy for Low Back Pain: Evidence-Based Procedural GuidelinesPAIN MEDICINE, Issue 2 2005W. Michael Hooten MD ABSTRACT Objective., This review was undertaken to outline the procedural limitations of the randomized controlled trials (RCTs) of radiofrequency (RF) neurotomy for low back pain. Second, the literature related to patient selection, diagnostic testing, and the technique of performing lumbar spine, RF neurotomy will be critically reviewed and analyzed. Based on these analyses, diagnostic and procedural guidelines will be proposed. Design., A Medline and EMBASE search identified three RCTs and two systematic reviews of RF neurotomy for low back pain. A similar search identified pertinent literature related to the method of patient selection for a diagnostic block, the medial branch and L5 dorsal ramus comparative block, and the anatomical and technical parameters of lumbar spine RF neurotomy. Results., Substantial procedural shortcomings were identified in all three RCTs. In the systematic reviews, these procedural limitations were not accounted for by the quality assessment of study design which resulted in an inaccurate estimate of clinical effectiveness. Analysis using likelihood ratios showed that screening criteria could increase the probability of zygapophysial joint pain before performing diagnostic blocks. Similar analysis showed that comparative medial branch blocks, rather than single blocks, must be used before RF neurotomy. Anatomical studies demonstrated that the shorter distal compared with the circumferential radius of the RF lesion necessitates placement of the electrode parallel to the course of the nerve along the base of the superior articular process. Conclusions., The evidence-based procedural guidelines provide consistent criteria for multisite studies that could enroll a sufficiently large homogenous study cohort. [source] The Surgical Anatomy of Lumbar Medial Branch Neurotomy (Facet Denervation)PAIN MEDICINE, Issue 3 2004Peter Lau FRACR ABSTRACT Objective., To demonstrate the validity of placing electrodes parallel to the target nerve in lumbar radiofrequency neurotomy. DESIGN., Previous data on the anatomy of the lumbar dorsal rami were reviewed and a demonstration cadaver was prepared. Under direct vision, electrodes were placed on, and parallel to, the L4 medial branch and the L5 dorsal ramus. Photographs were taken to record the placement, and radiographs were taken to illustrate the orientation and location of the electrode in relation to bony landmarks. Results., In order to lie in contact with, and parallel to, the target nerve, electrodes need to be inserted obliquely from below, so that their active tip crosses the neck of the superior articular process. At typical lumbar levels, the tip should lie opposite the middle two quarters of the superior articular process. At the L5 level, it should lie opposite the middle and posterior thirds of the S1 superior articular process. Conclusion., If electrodes are placed parallel to the target nerve, the lesions made can be expected to encompass the target nerves. If electrodes are placed perpendicular to the nerve, the nerve may escape coagulation, or be only partially coagulated. Placing the electrode parallel to the nerve has a demonstrated anatomical basis, and has been vindicated clinically. Other techniques lack such a basis, and have not been vindicated clinically. Suboptimal techniques may underlie suboptimal outcomes from lumbar medial branch neurotomy. [source] Technical Aspects of RadiofrequencyPAIN PRACTICE, Issue 3 2002M. Sluijter MD If the resulting current flows through a percutaneously introduced electrode, heat will be produced around the electrode because the body tissue acts as a resistor. RF can, therefore, be used to ablate nervous tissue in the treatment of chronic pain. This method has gained acceptance for percutaneous cordotomy and for the treatment of trigeminal neuralgia. For spinal pain, the method had little success initially, but since the introduction of small diameter instrumentation, the results have markedly improved. he mechanism of action of RF has not been challenged until recently even though there was awareness that some observations were not consistent with the heat concept. The formation of heat is not the only occurrence during RF treatment, however. The tissue surrounding the electrode is also exposed to the RF electric field. This exposure has a biological effect as has been demonstrated both in cells in a cell culture and in the exposure to RF of dorsal root ganglia, resulting in transsynaptal induction of early gene expression in the dorsal horn. The mode of action of RF is, therefore, uncertain at the moment. The method of pulsed RF is based on the concept that the production of heat has been a by-product of RF treatment and that the clinical effect is due to exposure to the electric field. In pulsed RF, the generator output is interrupted to allow for the elimination of heat in the silent period. The early results have been encouraging, but the results of controlled, prospective studies are not yet available. Since there are now 2 almost diametrically opposed views on the mode of action of RF, it is difficult to give recommendations for treatment. The decision is easy for indications for which heat RF has traditionally been contraindicated such as the treatment of peripheral nerves and trigger points. When the application of heat carries a potential risk, for instance if the dorsal root ganglion is the target structure, the use of pulsed RF is also recommended. As for the medial branch the situation is controversial. Since there are controlled studies available showing the effect of heat lesions, it is recommended that the technique should not be changed until further studies have been completed. Finally, the equipment for RF treatment is described and safety issues are discussed. [source] Paresthesia and hypesthesia in the dorsum of the foot as the presenting complaints of a ganglion cyst of the footCLINICAL ANATOMY, Issue 5 2010Diogo Casal Abstract Although ganglion cysts of the foot represent a substantial amount of lumps in this region, they rarely cause peripheral nerve symptoms. We describe the clinical case of a 43-year-old female with complaints in the previous three months of hypesthesia and paresthesia in the anterior portion of the medial half of the dorsum of her left foot that extended into the first interdigital cleft. She associated the start of her neurological symptoms to the appearance of a lump in the dorsum of the foot. A presumptive diagnosis of compression of the medial branch of the deep fibular nerve and of the medial dorsal cutaneous nerve in the dorsum of the foot by a ganglion cyst was made. Ultrasonography confirmed the cystic nature of the lesion and surgery allowed complete excision of a mass arising from the joint between the medial and intermediate cuneiform bones that was compressing the deep fibular nerve and the medial dorsal cutaneous nerve. Pathological examination confirmed that the lesion was a cystic ganglion. As far as the authors know, the simultaneous compression of the medial branch of the deep fibular nerve and of the medial dorsal cutaneous nerve in the dorsum of the foot by a ganglion cyst has not been described before. Clin. Anat. 23:606,610, 2010. © 2010 Wiley-Liss, Inc. [source] Arterial anatomy of the hallucal sesamoidsCLINICAL ANATOMY, Issue 6 2009Bjoern Rath Abstract The aim of this study was to analyze the arterial supply of the sesamoid bones of the hallux. Twenty-two feet from adult cadavers were injected with epoxide resin or an acrylic polymer in methyl methacrylate (Acrifix®) and subsequently processed by two slice plastination methods and the enzyme maceration technique. Afterwards, the arterial supply of the sesamoid bones was studied. The first plantar metatarsal artery provided a medial branch to the medial sesamoid bone. The main branch of the first plantar metatarsal artery continued its course distally along the lateral side of the lateral sesamoid and supplied it. The supplying arteries penetrated the sesamoid bones on the proximal, plantar, and distal sides. The analysis and cataloging of the microvascular anatomy of the sesamoids revealed the first plantar metatarsal artery as the main arterial source to the medial and lateral sesamoid bones. In addition, the first plantar metatarsal artery ran along the lateral plantar side of the lateral sesamoid bone, suggesting that this artery is at increased risk during soft-tissue procedures such as hallux valgus surgery. Clin. Anat. 22:755,760, 2009. © 2009 Wiley-Liss, Inc. [source] Bilateral Cerebellar Infarctions Caused by a Stenosis of a Congenitally Unpaired Posterior Inferior Cerebellar ArteryJOURNAL OF NEUROIMAGING, Issue 4 2001B. Gaida-Hommernick MD ABSTRACT Bilateral symmetrical cerebellar infarcts in the territory supplied by the medial posterior inferior cerebellar artery (PICA) branches are extremely rare. In the few cases published, it has not been possible to clearly pinpoint the cause of this infarct pattern. The authors present the case history of a 58-year-old man who had acute headaches accompanied by pronounced rotatory vertigo with nausea and vomiting. The neurological examination revealed bilateral cerebellar signs. Cranial magnetic resonance imaging showed bilateral, nearly symmetrical infarcts in the territory of the medial branches of both PICAs. These bilateral PICA infarctions were caused by a stenosis of an unpaired PICA originating from the left vertebral artery supplying both cerebellar hemispheres. [source] Morphological Investigations on the Circulus Arteriosus Cerebri in Mole-Rats (Spalax leucodon)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2008A. Aydin Summary The aim of the present study is to investigate the circulus arteriosus cerebri in mole-rats (Spalax leucodon). Six adult mole-rats were used for this purpose. Coloured latex was injected into the left ventriculus of the hearts of all the animals. After careful dissection, the circulus arteriosus cerebri (the circle of Willis) was investigated. The cerebrum and the cerebellum were supplied by the internal carotid- and the basilar arteries respectively forming the circulus arteriosus cerebri in mole-rats. In the investigated objects, the internal carotid- and the basilar arteries were not united directly and for this reason the circulus arteriosus cerebri was not formed completely in mole-rat. The branches supplying the medulla oblongata and the cerebellum originate from the basilar artery formed by union of the left and right vertebral arteries and the internal ophthalmic, the caudal cerebral, the choroid, the median cerebral, the rostral cerebral arteries originated from the internal carotid artery. After giving off the medial cerebral artery, the right and left rostral cerebral arteries on every two sides divided into the lateral and medial twin branches and by union of the lateral branches the internal ethmoidal artery, and by union of the medial branches, the ramus extending to facies medialis cerebri were formed. The ramus extending to the facies medialis cerebri was anastomosed with the branch of the caudal cerebral artery on the back of the corpus callosum. The last part of the basilar artery gave the two branches running toward the right and left side on the pontocrural groove (sulcus pontocruralis) and every one of these branches ramified into two rami. One of these rami formed into the rostral cerebellar artery and the other one extended to the tectum mesencephali. In conclusion, the arterial circle of the cerebrum and cerebellum was supplied by the internal carotid artery and the basilar artery respectively in mole-rats. [source] A review of the thoracic splanchnic nerves and celiac gangliaCLINICAL ANATOMY, Issue 5 2010Marios Loukas Abstract Anatomical variation of the thoracic splanchnic nerves is as diverse as any structure in the body. Thoracic splanchnic nerves are derived from medial branches of the lower seven thoracic sympathetic ganglia, with the greater splanchnic nerve comprising the more cranial contributions, the lesser the middle branches, and the least splanchnic nerve usually T11 and/or T12. Much of the early anatomical research of the thoracic splanchnic nerves revolved around elucidating the nerve root level contributing to each of these nerves. The celiac plexus is a major interchange for autonomic fibers, receiving many of the thoracic splanchnic nerve fibers as they course toward the organs of the abdomen. The location of the celiac ganglia are usually described in relation to surrounding structures, and also show variation in size and general morphology. Clinically, the thoracic splanchnic nerves and celiac ganglia play a major role in pain management for upper abdominal disorders, particularly chronic pancreatitis and pancreatic cancer. Splanchnicectomy has been a treatment option since Mallet-Guy became a major proponent of the procedure in the 1940s. Splanchnic nerve dissection and thermocoagulation are two common derivatives of splanchnicectomy that are commonly used today. Celiac plexus block is also a treatment option to compliment splanchnicectomy in pain management. Endoscopic ultrasonography (EUS)-guided celiac injection and percutaneous methods of celiac plexus block have been heavily studied and are two important methods used today. For both splanchnicectomies and celiac plexus block, the innovation of ultrasonographic imaging technology has improved efficacy and accuracy of these procedures and continues to make pain management for these diseases more successful. Clin. Anat. 23:512,522, 2010. © 2010 Wiley-Liss, Inc. [source] | |||||||||||||