Peripheral nerve injuries can cause serious health problems and result in lifelong disabilities. Although researchers have been studying peripheral nerve injuries, patients may not regain complete function of their muscles even after surgeries to repair their nerves are performed. However, animal studies have shown that after peripheral nerve cut and repair (muscle self-reinnervation), stretch-reflex in the affected muscles does not recover, which may affect the muscle electromyographic (EMG) activity of all muscle synergists, as well as joint kinematics. The aim of this study is to determine the effects of the self-reinnervation of the lateral gastrocnemius (LG) and soleus (SO) muscles in the hind limb of felines on the mean EMG activity of the intact synergist medial gastrocnemius (MG), as well as the moments at the knee and ankle joints during different walking conditions: level (0%), downslope (-50%), and upslope (+50%). The EMG activity and joint kinematics were recorded on the three different walking conditions before and 12 weeks after the self-reinnervation of LG and SO when these muscles recovered their activity. The self-reinnervation of the two muscles caused the MG EMG activity to increase for all walking conditions. However, the changes in the knee and ankle moments differed depending on the three different walking conditions. It was concluded that the changes in EMG and joint moments after self-reinnervation could be caused by the absence of stretch-reflex in the affected muscles and/or changes in physiological properties of muscles.

This thesis studies sensory innervation in mammals using an organotypic co-culture of spinal cord-dorsal root ganglion and skeletal muscle of embryonic rat, the histological changes of reinnervated muscle spindles after nerve section and the localisation of the calcium-binding protein calretinin in cat mechanoreceptor organs. The immediate importance of this project concerns the better understanding of how the normal process of development differs from reinnervation following nerve lesion or section. A range of classical and well defined materials and methods as been used in the work described. The thesis Is divided into Ove chapters: Chapter 1 reviews aspects of the mechanosensory organs which have been studied experimentally in relation to their sensory innervation, including proprioceptive muscle spindle development, reinnervation, and finally, the presence of the calcium-binding protein, calretinin in the mechanoreceptor organs. This provides an introduction and background to the work. Chapter 2 describes the organotypic organisation of spinal-cord, dorsal-root ganglia and skeletal muscle co-culture in vitro. Results show that slices of the spinal-cord, dorsal- root ganglia survive well under experimental conditions and can live for several weeks with feeding every 1-3 days. Sensory neurons can develop and grow in a medium without any additional promoting factor. The presence of structurally identifiable synapses indicates that other neurons are also maintained in culture and have functional connections. In the organotypic culture new muscle fibres can form either from the original explant or from the additional explant. In chapter 3 I describe two abnormal endings present in spindles of the tenuissimus of the cat that had been reinnervated following section of the nerve more than one year previously. The reconstruction of the endings of these two spindles supports the hypothesis of modulation of the primary-ending response by the mechanical properties of the intrafusal muscle fibres, rather than by intrinsic properties of the la afferent itself. They further indicate that, in the absence of a la afferent, intrafusal-fibre differentiation can be maintained by a group II afferent. Chapter 4 concerns the localisation of the calcium-binding protein calretinin, which was studied immunohistochemically in the abductor digiti quinti medius muscle of the cat hind limb. The calretinin immunoreactivity was found in some intrafusal fibres, the primary endings and the cqjsule of the muscle spindles and the sensory terminals of tendon organs and Paciniform corpuscles. The present findings contradict a recent hypothesis that calretinin is associated with rapid adaptation, but suggest that calretinin has a specific function in muscle proprioceptors. Finally, Chapter 5 outlines the conclusions of this study and gives some suggestions for continuation of the work in the future.

Bladder incontinence in patients who suffer from sacral spinal cord injury can wreak havoc on one's quality of life. A 2012 survey suggests that patients who sustain spinal cord injury prioritize the recovery of bladder function over other faculties. With about 12,000 new spinal cord injury cases reported in the United States each year, finding ways to combat the disabilities that result from lower spinal cord dysfunction should be of utmost importance to the scientific research community. Prior to studying the effects of surgical reinnervation on the bladder after long-term decentralization, it was critical to understand the effects that decentralization had on the integrity of both smooth muscle and intramural nerves of the bladder, the function of which could determine the success of surgical reinnervation. Chapter 2 describes in vivo stimulation, ex vivo smooth muscle contractility studies, and immunohistochemical techniques that were used to assess the condition of the functional components of the bladder. Collective results showed that although pelvic plexus-induced stimulation decreased when decentralization included the bilateral transection of the L7 dorsal root, smooth muscle cells and intramural nerves maintained their function after long-term bladder decentralization. Thus, preservation of at least some nerve activity may allow for successful surgical reinnervation after long-term injury. Following confirmation of smooth muscle and intramural nerve viability after decentralization, we sought to determine if nerve transfer after long-term decentralization restores bladder function in canines. In Chapter 3, we detail both decentralization and surgical reinnervation procedures used in our model. Briefly, decentralization of the bladder included bilateral transection of hypogastric nerves, as well as all spinal roots caudal to L7, with a subset of animals undergoing additional transection of the dorsal root of L7. One year after decentralization, animals that showed consistent loss of sensory and motor function underwent surgical reinnervation, which included the bilateral transfer of part of the obturator nerve to the anterior vesical branch of the pelvic nerve and the semimembranosus branch of the sciatic nerve to the pudendal nerve. Behavioral observations, in vivo stimulation of transferred nerves, and retrograde tracing studies were used to explore the efficacy of reinnervation on both sensory and motor components of bladder function. Ultimately, results showed that the new neuronal pathways created by nerve transfer can restore bladder sensation and possibly motor function in lower motor neuron-lesioned canines. Beyond the effects of surgical reinnervation on bladder function, we were interested in taking a closer look at the mechanisms that dictate function after decentralization and reinnervation (Chapter 3). Based on our previous work that found that transfer of somatic nerves resulted in bladder smooth muscle expression of a nicotinic receptor subunit thought to be expressed primarily in striated muscles, we were interested in assessing changes in the profile of nicotinic receptors responsible for bladder function. Ex vivo smooth muscle contractility studies showed that response to nicotinic receptor agonists were not altered after decentralization or reinnervation. Furthermore, the α1 nicotinic receptor subunit was expressed in bladder smooth muscle across all surgical groups. Future studies are necessary to better elicit the physiological relevance of these nicotinic receptors in the bladder. Additionally, due to the complexity of surgical reinnervation, it was important to understand all contributions to bladder innervation (Chapter 4). We previously identified that cells in the ventral horns of spinal cord levels rostral to the sacral cord can directly innervate the bladder via retrograde tracing. Because these direct inputs were not in proximity of the spinal root transections made during decentralization, we wanted to know how decentralization and reinnervation impacted their effects on the bladder when stimulated. L2-mediated detrusor contractions were significantly decreased by transection of the hypogastric nerves, suggesting that many of the nerves originating from the L2 cord are sympathetic in nature; however, treatment with phentolamine did not completely eliminate the increase in pressure in response to L2 stimulation. Therefore, the remaining inputs likely act upon the bladder through a yet undefined pathway. The quantity of positively labelled cells did not change in sections of the L2 ventral horn across all surgical groups, suggesting no change in the contribution of direct inputs to bladder innervation. Finally, anatomical feasibility of the obturator and semimembranosus branch of the sciatic nerve transfers has been assessed in an unembalmed cadaver, the results of which have not yet been published. Overall, this research gives us reason to believe that surgical reinnervation is a viable option for patients who develop lower neurogenic bladder after injury to the sacral cord, cauda equina, or peripheral nerves mediating bladder function. / Biomedical Sciences

La voie olivocérébelleuse (OCP) comprend les fibres grimpantes (CFs), terminaisons axonales des neurones de l'olive inferieure (ION), et leurs cibles, les cellules de Purkinje (PCs). La OCP suit une topographie hautement organisée. A la suite d'une lesion unilatérale de la OCP mature, l'application locale du facteur trophique ‘BDNF’ dans le hemicervelet dénervé induit la reinnervation fonctionnelle des PCs par les CFs. L'objectif de ce travail a était de comprendre les mécanismes activés par le BDNF permettant la plasticité post-lésionnelle dans le OCP mature. Avec un modèle ex vivo chez la souris, nous avons montré que l’injection de BDNF dans le cervelet dénervé augmente la croissance des branchements transverses des CFs intactes. Cette réponse est médiée par l'augmentation de l’expression de Pax3 dans l'ION intact. La surexpression du Pax3 dans l’ION augmente le niveau de PSA-NCAM dans le hemicervelet dénervé, probablement sur les CFs. Cette expression de PSA-NCAM est nécessaire et suffisante pour la réinnervation CF-PC. Nous proposons que la plasticité activée par le BDNF dans l'OCP mature implique le Pax3 et le PSA-NCAM dans l’ION, qui sous-tendent la genèse des branchements des CFs et la reconnaissance correcte des PC dénervés. Pendant le développement de la OCP, la plasticité post-lésionnelle spontanée est plus importante, permettant la compensation anatomique et fonctionnelle. Dans notre modèle ex vivo au stade immature, nous avons montré que cette plasticité spontanée implique l'expression de Pax3 et de PSA-NCAM. Ces résultats suggèrent que la reinnervation post-lésionnelle dans la OCP mature active certains mécanismes de la plasticité développementale. / In the olivocerebellar pathway (OCP) the afferent climbing fibres (CFs), which are the terminal axon projections of the inferior olivary nucleus (ION), innervate cerebellar Purkinje cells (PCs). Following unilateral transection of mature OCP, the addition of the neurotrophic factor BDNF into the denervated cerebellum induces functional CF reinnervation of PCs. What mechanism underlies the BDNF-activated plastic window in the mature OCP and whether recapitulates developmental plasticity remains unknown. Using an optimized ex vivo model of the mouse OCP, we have found that the addition of BDNF into the de-afferented hemicerebellum induces both the outgrowth and elongation of transverse branches from intact CFs. This BDNF-induced plastic response is mediated by the up-regulation of the expression of transcription factor Pax3 in the intact ION. Increased pax3 gene in the ION up-regulates polysialic acid-neural cell adhesion molecule (PSA-NCAM), most likely in the olivocerebellar axons, which was found to be necessary and sufficient for CF reinnervation to PCs. We propose that the BDNF-activated plastic mechanism in the mature OCP involves the afferent Pax3 and PSA-NCAM, which underlies the sprouting of CFs and their appropriate recognition of denervated PCs. Early postnatal OCP shows a spontaneous plasticity following lesion that compensates anatomically and functionally for PC denervation. Using our ex vivo model of the OCP, we found that developmental post-lesion plasticity intrinsically activates and depends on the expression of Pax3 and PSA-NCAM. These results suggest that BDNF treatment in mature OCP reactivates some steps of developmental plasticity mechanisms.

No description available.

No description available.

Spinal cord injuries and other neurological disorders can disturb the regulation of normal bladder function including continence and micturition. Developing new neuronal pathways by surgically rerouting nerves is a potential approach for restoring bladder function. Our laboratory successfully rerouted somatic nerves to the anterior vesical branch of the pelvic nerve to reinnervate the bladder muscle in canines. Electrical stimulation of these transferred nerves induced detrusor pressure and bladder emptying and we confirmed regrowth of these rerouted nerves using retrograde neurotracing methods. In these studies, reinnervation was proved at 1st and 3rd months after decentralization. We believe that our aim of developing an approach to surgically reinnervate the bladder after long-term decentralization is critical to the success of the reinnervation surgery due to the possibility that patients would delay having a surgery until they try other non-surgical approaches or therapies. We also demonstrated the reinnervation of urethral and anal sphincters by femoral to pudendal nerve transfer after sacral ventral root transection to restore continence. However, these studies did not demonstrate the reinnervation of bladder, urethra and anal sphincter, all in same animal that would be helpful to human patients with lower motor neuron lesioned bladders to restore both continence and emptying. Therefore, prior to applying these surgical procedures to human patients, further investigation is required to prove the effectiveness of nerve transfer strategies in this canine model using multiple experimental techniques. This dissertation is a part of a larger project in canines examining whether surgical rerouting of obturator to pelvic nerve and sciatic to pudendal nerve allows restoration of bladder, urethral and anal sphincter functions, including continence (storage) and emptying (voiding and defecation) functions, in lower motor neuron lesioned bladders. In this study, it was aimed to explore bladder and urethral reinnervation using behavioral observation and in-vivo electrophysiological techniques. In order to completely prove that the reinnervation surgeries are responsible for restoration of bladder and urethral functions, it was first necessary to demonstrate the absence of these functions in animals with long term decentralized bladders and to determine whether the same animals were able to recover functions after reinnervation. In specific aim 1, we addressed this goal by tracking squat-and-void behaviors at monthly intervals after decentralization and reinnervation, using home cage video recordings and evaluation of bladder sensation and emptying after bladder filling. Immediately prior to euthanasia, reinnervation was also explored by electrical stimulation of transferred nerves to evaluate motor function. Retrograde neuronal tracing was also performed to explore sensory reinnervation. Results showed evidence of functional restoration of bladder and urethral function in reinnervated animals based on behavior observation and electrical stimulation of transferred nerves. Also, regrowth of neuronal cells in the new neuronal pathways was observed that were developed by the nerve transfer surgeries. This study also aimed to establish an electroneurogram recording method (part of in-vivo electrophysiological experiments) to explore afferent (sensory) neuronal activity in transferred nerves induced by bladder filling. However, the extraction of neuronal activity from the peripheral nerves is a challenging task. Several factors including noise, interference from surrounding muscle activities and the electronic components can affect these microvolts level recordings. Choice of recording electrode in configuration with the whole recording setup also plays a significant role while performing these low amplitude signal recordings. In specific aim 2, we addressed this issue by refining electroneurogram recording techniques to obtain high strength signal during multifiber recording. We first developed custom electrodes, suitable for varying nerve diameters and available implantation sites, were tested for functionality. Then, we performed multiple testing using these electrodes with different amplifiers to calibrate noise in saline. Testing results helped to establish the recording setup suitable for in-vivo experimental environment. Later, these refined techniques were applied to record afferent (sensory) activity of sciatic nerves and afferent (sensory) and efferent (motor) activity of hypogastric nerves in rats. Based on the recording results, it was aimed to employ similar techniques in order to record nerve activity in the canine model. Prior to applying these refined techniques to explore sensory reinnervation from new neuronal pathways after nerve transfer surgeries, in specific aim 3, we aimed to assess the hypogastric nerve activity in normal intact and acutely lumbosacral decentralized bladders using these refined techniques. The effects of electrical stimulation of hypogastric nerves or lumbar roots on detrusor pressure were determined, as were effects of isoflurane versus propofol anesthetics on hypogastric nerve stimulation evoked pressure. Hypogastric nerve activity was recorded using custom-made bipolar cuff electrodes during bladder filling. To confirm or refute that any increase in electroneurogram during bladder filling is due to afferent activity from the end organ, the hypogastric nerve was transected between the recording electrode and the spinal cord and the effects of bladder filling on afferent but not efferent activity were recorded. Results showed that electrical stimulation of hypogastric nerves evoked low amplitude detrusor pressures that did not differ between the two anesthetics. Upper lumbar (L2) ventral root stimulation evoked detrusor pressures were suppressed, yet not eliminated after transection of hypogastric nerves and all spinal roots below L5. Afferent and efferent hypogastric nerve activity did not change with bladder filling in neuronally intact bladders but decreased in decentralized bladders. No change in afferent activity were observed during bladder filling in normal intact and decentralized bladders. Overall findings in this research indicate that the new neuronal pathways created by nerve transfer can restore bladder sensation and emptying function in lower motor neuron-lesioned canines. A more complete decentralized bladder model needs to include transection of both the lumbosacral spinal roots innervating the bladder and the hypogastric nerves prior to performing nerve transfer surgeries. The refined electroneurogram recording methods may be suitable for evaluating the effectiveness of nerve transfer surgeries by monitoring the sensory activities of the transferred nerve. / Electrical and Computer Engineering

No description available.

Preface: The research about product development of a prosthetic socket was conducted by two students from Mälardalen University, department of Innovation, Design, and Technology. Background: The most recent public survey shows that an estimated 5 million people in China are amputees, out of which a significantly large portion are below-elbow amputees. Sockets sold to below-elbow amputees are equipped with only two surface electromyography sensors, has low comfortability, has problems with perspiration, and a high weight. The current standard for socket manufacturing has not changed in decades. Research Questions: The following research questions have determined the direction of the research: (1) What measurable factors contribute to a convenient and ergonomic feature design in prosthetic socket from the end-user’s perspective? (2) How can the weight and functionality be improved to achieve a prosthetic socket more suited to the end-user, with respect to the existing prosthetic socket? (3) Which material and manufacturing method is suitable for producing cost-effective and customized prosthetic sockets? Research Method: The research was guided by the 5th edition of Product Design and Development by Ulrich & Eppinger (2012) where the product development process described in five of the six phases from planning to test and refinement were utilized. The data collection and analysis techniques performed in this research was guided by Research Methods for Students, Academics and Professionals by Williamson & Bow (2002). Interviews were conducted with five different stakeholders to find specifications of requirements and concretize subjectivism of what defines quality and ergonomics. Implementation: Currently, below-elbow amputees order sockets from orthopedic clinics. The socket was identified as a product of Ottobock. Investigations were made to find optimal solutions to the specification of requirements. Results: The development of a socket concept was designed for additive manufacturing using a multi-jet fusion printer. Analysis: This concept had significant improvements to parameters: higher grade of customizability, 30 % reduced weight, 48 % cost reduction, a new production workflow with 93,5 % automation, and a 69 % reduction in manual work hours. Conclusions: The data of the research strongly indicate existing potentials in enhancing socket design techniques and outputs by implementation of additive manufacturing processes. This can prove to be beneficial for achieving more competitive prosthetics and associated services. / Förord: Denna forskning om produktutvecklingsprocessen av en armprotes genomfördes av två studenter från Mälardalens universitet, avdelningen för innovation, design och teknik. Bakgrund: Den senaste offentliga undersökningen visar att cirka 5 miljoner människor i Kina är amputerade, varav en betydligt stor del är under-armbågsamputerade. Armproteser som säljs till underarmsamputerade individer är utrustade med endast två yt-elektromyografiska sensorer, har låg komfort, har problem med perspiration och hög vikt. Den nuvarande standarden för armproteser har inte förändrats under årtionden. Forskningsfrågor: Följande forskningsfrågor har bestämt riktningen för forskningen: (1) Vilka mätbara faktorer bidrar till en praktisk och ergonomisk funktionsdesign i underarmsproteser ur slutanvändarens perspektiv? (2) Hur kan vikten och funktionaliteten förbättras för att åstadkomma en underarmsprotes som är bättre anpassad för slutanvändaren med avseende på den befintliga underarmsprotesen? (3) Vilket material och tillverkningsmetod är lämpligt för att producera kostnadseffektiva och anpassade underarmsproteser? Forskningsmetod: Forskningsmetoden styrdes av den femte upplagan av Product Design and Development av Ulrich & Eppinger (2012) där produktutvecklingsprocessen är uppdelad i sex faser. I denna forskning användes de fem första faserna från planering till testning och justering. Tekniker för datainsamling och analys som användes i denna forskning styrdes av Research Methods for Students, Academics and Professionals av Williamson & Bow (2002). Intervjuer genomfördes med fem olika intressenter för att hitta kravspecifikationer och för att konkretisera subjektivitet för vad som definierar kvalitet och ergonomi. Implementering:  Underarmsamputerade individer beställer för närvarande armproteser från ortopediska kliniker. Armprotesen identifierades som en produkt av Ottobock. Undersökningar gjordes för att hitta optimala lösningar för kravspecifikationen. Resultat: Konceptutvecklingen av en armprotes utformades för additiv tillverkning med hjälp av en multi-jet-fusion-skrivare. Analys: Det här konceptet hade betydande förbättringar av parametrar: högre grad av anpassningsbarhet, 30 % minskad vikt, 48 % kostnadsreduktion, ett nytt produktionsflöde med 93,5 % automatisering och en 69 % minskning av manuella arbetstider. Slutsatser: Data från denna forskning indikerar att det finns starkt potential för att förbättra designtekniker och utgångar av underarmsproteser genom implementering av additiva tillverkningsprocesser. Detta kan visa sig vara fördelaktigt för att uppnå mer konkurrenskraftiga proteser och tillhörande tjänster.

A contração muscular gerada por impulsos elétricos provenientes de duas fontes nervosas distintas pode ser alternativa no tratamento de lesões do plexo braquial e na paralisia facial. O objetivo desta tese foi avaliar e comparar diferentes técnicas de reinervação dupla com a técnica de reinervação única do músculo gastrocnêmio em ratos. Cinquenta ratos Wistar adultos, após terem seu nervo fibular direito seccionado, foram divididos em cinco grupos com relação ao procedimento realizado no nervo tibial: controle (C); seccionado (S); neurorrafia término-terminal (TT); neurorrafia primária associada à transferência nervosa fibular para tibial de maneira término-lateral (TL); e neurorrafia término-terminal convergente entre os cotos proximais dos nervos tibial e fibular com o coto distal do nervo tibial (TTC). Os resultados foram avaliados 12 semanas após o experimento por meio do teste da marcha, eletromiografia, índice de massa do músculo gastrocnêmio e contagem axonal no coto distal do nervo tibial. Os grupos de reinervação dupla (TL e TTC) revelaram maiores resultados funcionais (p < 0,05) em relação ao grupo de reinervação única (TT). O grupo TTC apresentou maior amplitude (p=0,006) e maior latência (p=0,041) do que o grupo TT. Em relação ao índice de massa muscular, não houve diferença entre os grupos de reinervação (p > 0,705). A análise histológica revelou maior densidade axonal no grupo TTC em relação ao grupo TT (p=0,001) e ao grupo TL (p=0,002). Ambas técnicas de dupla reinervação revelaram recuperação funcional do músculo gastrocnêmio mais precoce e maior quando comparadas à técnica de reinervação única (TT). Os animais do grupo TTC apresentaram maior número de axônios regenerados no coto distal do nervo tibial do que os do grupo TT e TL / Muscle contraction generated by electrical impulses simultaneously originating from two different neural sources may be an interesting treatment alternative for facial palsy and brachial plexus injury. The purpose of this thesis was to evaluate and compare distinct double reinnervation techniques with single reinnervation technique of gastrocnemius muscle in rats. Fifty adult Wistar rats underwent transection of their right peroneal nerve and were divided into five groups related to tibial nerve procedure: the control group (C), tibial nerve section group (S), tibial nerve end-to-end neurorrhaphy (EE) group, tibial nerve primary repair associated with end-to-side peroneal-to-tibial nerve transfer (ES) group, and tibial nerve repair by convergent end-to-end neurorrhaphy between the proximal stumps of the tibial and peroneal nerves to the distal stump of the tibial nerve (CEE) group. The outcomes were assessed 12 weeks after the experiment by use of a walking track, electromyography, gastrocnemius muscle mass index, and histomorphometric analysis of the distal tibial nerve. The double reinnervation groups (ES and CEE) showed greater functional recovery (p < 0.05) than the single reinnervation group (EE). The CEE group showed greater amplitude (p=0.006) and higher latency (p=0.041) than the EE group. There was no difference in the muscle mass index among the reinnervation groups (p > 0.705). Histologic analysis revealed greater axonal density in the CEE group than EE group (p=0.001) and ES group (p=0.002). The double reinnervation techniques showed earlier and greater functional recovery of the gastrocnemius muscle than did the single reinnervation technique. The CEE group showed a higher number of regenerated axons in the distal tibial nerve stump