Adequate hemostasis is a prerequisite in neurosurgery, to prevent dramatic postoperative bleedings and their consequences.Different sorts of local hemostatic agents have been developed, with a variable efficacy.Some of them have been used for years, none being perfect.The residual presence of these agents may behave as foreign bodies, and induce inflammation, infection, and even delayed bone growth.Safety is an other concern since most of modern agents contain more or less human and animal components.We are going to review the history of those agents, their different categories, compare them and try to establish some guidelines when using them, with their different indications. Hemostasis (basis)Hemostasis comes from the coordinated activation of platelets and plasma clotting factors to form a platelet fibrin clot.Two processes, primary and secondary hemostasis activation of the clotting cascade id done by collagen for the intrinsic pathway, and the extrinsic pathway is activated by the release of tissue factors from the damaged zone.The two converge ento the common pathway which begins with the conversion of Factor X to Xa, the conversion of prothrombin to thrombin, which is integral in clot stabilization via fibrin.This common pathway is facilitated by Factor V (Hawiger 1987). HistoryFrom the beginning of the neurosurgical practice, local hemostatic agents have proved to be very useful completing the more classical use of the electrocoagulation whatever its type, mono or bipolar or sometimes laser. First attempts Auto or hetero-muscle applicationUntil the early 1950, neurosurgeons used as topical hemostatic agents fresh chicken breast which was delivered to the operative theatre just before the beginning of the operation.Electrocoagulation device was not very good, and they often had to apply the chicken flesh www.intechopen.comExplicative Cases of Controversial Issues in Neurosurgery 506 on the brain during ten minutes while washing the field with warm serum, and removed it before closing the dura.Fresh muscle harvested from the temporal site or the thigh is still commonly used for extradural dural hemostasis and may be left in situ. How to referenceIn order to correctly reference this scholarly work, feel free to copy and paste the following:

Muscle fiber action participates in a true contractile machinery associated with noncontractile components providing mechanical stability. The myofibril, the muscle fiber subentity, has an extremely consistent architecture, composed of longitudinal cylindrical units called sarcomeres, the skeletal muscle length functional unit, a highly important place in the transduction of chemical signal into mechanical contractile energy, for the most part mediated by calcium. The sarcoplasmic reticulum is the other major component of muscle fiber and is dedicated to calcium storage, liberation and distribution to the fiber, under the influence of action potential propagation. This phenomenon is called excitation-contraction coupling. This paper explores muscle anatomy from its main embryologic stages of development to its histochemical specificity, including its molecular constitution, and details the main morphofunctional relations supporting muscle contraction. (C) 2009 Published by Elsevier Masson SAS.

Les agents hémostatiques locaux sont d’usage quotidien en neurochirurgie, et ce depuis les premiers temps de cette spécialité. Les produits cellulosiques hyperoxydés comme les différentes colles biologiques ont démontré à la fois leur innocuité et leur efficacité tout en aidant le neurochirurgien à obtenir une hémostase stable, dans des situations où les moyens d’hémostase classique sont inutilisables, voire contre-indiqués.

Over the last decades microvascular decompression (MVD) has been established as the curative treatment of the primary Hemifacial Spasm (HFS), proven to be linked in almost all cases to a neurovascular compression of the facial nerve. Because the disease is not life-threatening and MVD not totally innocuous, efficacy and safety have to be weighted before decision taken of indicating surgery. The authors have been charged by the French Speaking Society of Neurosurgery to conduct a detailed evaluation of the probability of relief of the spasm that MVD is able to obtain, together with its potential complications. For the review, the authors have gone through the reports available from the Pubmed system. Eighty-two publications have been read and analysed, totalizing more than 10,000 operated cases. In most series, the percentage of patients with total relief ranged between 85% and 90%. Relief was obtained after a certain delay in as many as in 33% ± 8% of the patients in many series. For those, delay lasted around one year in 12% of them. When effect of MVD was considered achieved, relief remained permanent in all but 1%–2% of the long-term followed patients. As regards to complications, risk of permanent cranial nerve deficit was evaluated at 1%–2% for facial palsy, 2%–3% for non-functional hearing loss, 0.5%–1% for lower cranial nerve dysfunction. Risk of stroke was at 0.1% and mortality at 0.1%. CSF leakage and related complications could be reduced at less than 2% in most series provided careful closing techniques be applied. Complications were at a higher rate in repeated MVD. MVD is an effective curative method for almost all the patients affected with primary HFS. Because MVD for HFS is functional surgery, scrupulous consideration of its potential risks, together with the ways to avoid complications are of paramount importance. When MVD is estimated to have failed, it is wise to wait one year before considering to repeat surgery, as number of patients may benefit from delayed effect. This is the more so as important as repeated surgery entails a higher rate of complications.

Peripheral nerve injuries are frequent and generate significant deficits. Their treatment sometimes leads to functional recovery but is mostly incomplete or unpredictable, despite the regular use of sophisticated repair techniques. The clinician must clearly understand the peripheral nervous system's responses to injury, which reveal surprising degenerating and spontaneous regenerating abilities. This potential recovery is a peripheral nervous system specificity and follows a relatively complex process. Peripheral neurons depend on glial cell structure and metabolism, inducing a global and dynamic response of the whole axon environment, even in cases of focal lesion, modulated by the initial type and mechanism of injury. Today's progress remains insufficient to improve functional prognosis significantly, but a better understanding of peripheral nerve regenerating processes has opened the door to new medical and surgical advances.

Peripheral nerve surgery requires a certain level of specialization. Surgeons must have solid knowledge of morphological anatomy of the different segments to be explored, decompressed, repaired, or even neurotized. This paper describes the most common approaches to the peripheral nerves of the upper limb.

Background/Objective. - Peripheral selective neurotomy is commonly used to treat the equinus spastic foot (tibial nerve), but is less frequently used in treating upper limb spasticity, because of the complexity of the articular deformities and the complex innervations of the different muscles. We present our experience and the long-term results of this surgery based on a retrospective series of 22 patients with a disabling spasticity of the upper limb.Methods. - Between 2003 and 2006, neurotomies were performed in 22 patients with disabling spasticity of the upper limb despite optimal medical treatment. Patients were evaluated before and after the surgical procedure. Twelve clinical parameters were studied for describing deformity (resting position and amplitude of each joint), spasticity (Ashworth and Tardieu scores), and the functional impacts of the spasticity.Results. - At long-term follow-up, A parameters were improved from the surgery, both in terms of spastic symptoms (highly significantly decreased in Ashworth and Tardieu scores) and the deformity of the upper limb (e.g., 60 degrees increase in the extension of the elbow). Pain, active amplitude, and functional impact scores were also statistically significantly improved after surgery. The mean satisfaction index was 7/10 (+/- 1.6).Conclusions. - Selective neurotomy is an effective treatment for patients with a disabling and excessive spasticity in the upper limb. It provides a long-term, objective improvement based on analytical and functional parameters. We emphasize the importance of accurate clinical evaluation and surgical planning. Finally, excessive time to treatment seems to be an important factor for recurrence or incomplete efficiency of the procedure. (C) 2009 Elsevier Masson SAS. All rights reserved.

The peripheral nerve provides the pathway for motor, sensory and vegetative axons belonging to the peripheral nervous system. It transmits information between these neurons and their peripheral effectors in both directions (sensory receptors, skeletal muscles and viscera). The afferences to the periphery correspond to the nerve motor content, whereas efferences from the periphery, in charge of delivering information to the central integrators, correspond to nerve-sensitive content. This information support depends on intrinsic properties of the nerve itself. Recent advances in cellular and molecular biology have provided a better understanding of nerve physiology, which are reviewed here as an indispensable basis to the study of its pathology.

In 2007, four patients where implanted with the Restore neurostimulation system for intractable chronic leg pain at the Poitiers Hospital. The potential for improving the patients' quality of life and medical-economic concerns motivated this choice for these highly selected patients. In this paper, we propose brief clinical case reports and discuss the reasons for choosing this new rechargeable system, even though it was initially more expensive than the standard neurostimulation system (Itrel 3). All patients receiving implants declared that they were very satisfied with the quality of stimulation provided by Restore and noted a significant improvement in their quality of life. If this solution becomes advantageous from an economic point of view, clinical data should lend support to the utility of this technological innovation for patients who have hitherto been in treatment failure.

It has been shown that the onset of a central nervous system lesion in the rat results in morphological modifications of the peripheral nerves and the underlying neuromuscular junctions, without suggesting a functional correlation between recuperation of motor functions and sublesional metabolic activity. Using double lesion localization (T2 and T6) in a spinal rat model has nevertheless pointed out the functional importance of the T2-T6 metameric interval in the reinnervation phenomena observed, raising the problem of spinal generation in locomotor movements. Motivated by electrophysiological data that have given support to the concept of an anatomic substrate for these intramedullary rhythm generators, we attempted to establish a relation between the functional recuperation possible after a central nervous system lesion and modifications within the metabolism of the underlying neuromuscular system. We notably focused on Na/K-ATPase, whose crucial role in neuromuscular transmission has been evidenced. This paper proposes to demonstrate the involvement in the mechanisms of metabolic regulation after trans-synaptic denervation, i.e., a central nervous system lesion. Our study includes the Na/K-ATPase activity analysis on the sublesional peripheral nerve and the combined analysis of the expression of different RNA messengers within the corresponding muscle groups. We have also investigated the spatiotemporal organization of the compensating processes of the nerves underlying the lesion using magnetic resonance spectroscopy.

The sarcoplasmic reticulum (SR) plays a fundamental role in excitation-contraction coupling, which propagates the electric signal conversion along the muscle fiber's plasmic membrane to a mechanical event manifested as a muscle contraction. It plays a crucial role in calcium homeostasis and intracellular calcium storage control (storage, liberation and uptake) necessary for fiber muscle contraction and then relaxation. These functions take place at the triad, made up of individualized SR subdomains where the protein-specific organization provides efficient and fast coupling. Ryanodine receptors (RyR) and dihydropyridine receptors (DHPR) mainly act in calcium exchanges in the SR. This particular structural and molecular architecture must be correlated to its functional specificity.

Peripheral nerve tumors are most often benign tumors of the nerve sheath; uncommonly they come from the nerve cells or are metastatic tumors. A precise diagnosis is required for well-adapted and effective treatment, as is good knowledge of fibromatosis diseases. In some cases, the diagnosis of the nerve tumor will lead to a diagnosis of phakomatosis. Surgical treatment must be clearly discussed, which, in case of schwannomas gives very good functional results. Primitive malignant tumors remain an unsolved therapeutic problem.

This paper explores the specific roles of sprouting stimuli, perisynaptic Schwann cells and neuromuscular activity in axonal sprouting at the neuromuscular junction in partially denervated muscles. As for sprouting stimuli, insulin-like growth factor II which is generated from inactive muscle fibers in partially denervated and paralysed skeletal muscle is described. Likewise, perisynaptic Schwann cells can induce and guide axonal sprouting in partially denervated muscles. Finally, excessive neuromuscular activity significantly reduces bridging of the perisynaptic Schwann cell processes between denervated and innervated endplates and thereby inhibits axonal sprouting in partially denervated muscle. The lack of neuromuscular activity is also harmful in axonal sprouting, probably by impeding calcium influx into the nerve.

The peripheral nerve provides the pathway for motor, sensory, and vegetative axons belonging to the peripheral nervous system. It transmits information between these neurons and their peripheral effectors in both directions (sensory receptors, skeletal muscles, and viscera). The afferences to the periphery correspond to the nerve motor content, whereas efferences from the periphery, in charge of delivering information to the central integrators, correspond to nerve-sensitive content. This information support depends on the intrinsic properties of the nerve itself. Peripheral nerve injuries are frequent and generate significant deficits. Their treatment sometimes leads to functional recovery but is mostly incomplete or unpredictable, despite the regular use of sophisticated repair techniques. The clinician must clearly understand the peripheral nervous system's responses to injury, which reveal surprising degenerating and spontaneous regenerating abilities. This potential recovery is a peripheral nervous system specificity and follows a relatively complex process. Peripheral neurons depend on glial cell structure and metabolism, inducing the global and dynamic response of the whole axon environment, even in cases of focal lesion, modulated by the initial type and mechanism of injury. Today's progress remains insufficient to improve functional prognosis significantly, but a better understanding of peripheral nerve regenerating processes obtained in cellular and molecular biology has opened the door to new medical and surgical advances. (C) 2009 Published by Elsevier Masson SAS.