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Introduction: "Watch and wait"-strategies from 3 to 6 months for peripheral nerve injuries are standard of care in specialized centers. However, this contradiction between delayed decision-making and the demand for fast reinnervation, especially of the motoric endplate, has not yet been overcome. Therefore, this study aimed to investigate the time-sparing effects by accelerated decision-making due to the complementary MR-neurography application combined with established diagnostics like electroneurography and neurosonography from the first admission to the determination of the treatment plan., Patients and Methods: A retrospective matched-pair chart review analysis with Supplementary MR-neurography in the period between 2014 and 2017 was designed. Matching was performed by the parameters of nerve type, localization of the nerve injury, patient age, and treatment of the injury. Twenty-nine patients were included and matched in the study. MR-neurography imaging was performed by a 3T magnetic resonance imaging with a sampling perfection with application optimized contrasts using different flip angle evolution short tau inversion recovery sequence for the brachial plexus and gradient echo accurate fast imaging with steady-state free precession sequence for the upper extremity. Time to decision-making was investigated for or against a surgical intervention for patients with or without a Supplementary MR-neurography., Results: In general, MR-neurography accelerated decision-making for 28 days, with results of 37.5 + 5.4 days with Supplementary MR-neurography and 65.3 + 9.7 days without Supplementary MR-neurography (p = .05). Within the first 90 days following trauma, patients with MR-neurography (38.2 ± 7.7 days) benefit under a significant faster decision-making (p = .05) than patients without MR-neurography (79.0 + 14.2 days). After 90 days, no evidence of accelerated decision-making was found with the addition of MR-neurography (p = .6). In 10 of the 29 patients, despite additional electroneurography and neurosonography, no decision could be made and the MR-neurography has been used primarily as a diagnostic tool., Conclusion: MR-neurography has significant time-sparing effects on the decision-making for approximately 4 weeks within the first 90 days after the trauma. This may help overcome the paradigm of "watch and wait"-strategies during the first 3-6 months after the peripheral nerve injury., (© 2021 Wiley Periodicals LLC.)

The assessment of already installed anchorages for a possible exceeding of the service load level is a question that is gaining more and more importance, especially in building maintenance. Bonded anchors are of particular interest here, as the detection of a capacity reduction or load exceedance can cause damage to the concrete-bonded mortar behavior. This article investigates the extent to which ultrasonic methods can be used to make a prediction about the condition of anchorages in concrete and about their load history. A promising innovative assessment method has been developed. The challenges in carrying out the experimental investigations are the arrangement of the transducers, the design of the test set-up and the applicability of direct, indirect or semidirect ultrasonic transmission. The experimental investigations carried out on a test concrete mix and a bonded anchor system show that damage to the concrete structure can be detected by means of ultrasound. The results indicate the formation of cracks and therefore a weakening of the response determined by means of direct, indirect and semidirect ultrasonic transmission. However, for application under non-laboratory conditions and on anchors with unknown load history, the calibration with a reference anchor and the identification of the maximum load is required. This enables a referencing of the other loaded anchors to the unloaded conditions and allows an estimation of the load history of individual anchors.

Introduction: Nerve transfers are an important tool to restore muscle function. Despite their popularity in reconstructive surgery, their effects on the motor unit remain largely unknown. Therefore, a realistic animal model is needed for the upper extremity, which is where the majority of nerve transfers are conducted. This work shows different upper extremity nerve transfer models in the rat, where elbow flexion was restored with different types of nerve transfer in adult and neonatal rats., Methods: Anatomy and microsurgical feasibility was first evaluated in 10 adult and 5 neonate Sprague Dawley rats. In 40 rats (30 adult and 10 neonate), a nerve transfer of the whole ulnar nerve or just the deep branch was performed to reinnervate the long head of the biceps muscle. After 12 weeks of regeneration, the transfer was evaluated for functional aspects such as muscle force and weight., Results: Neural anatomy was constant in all rats. All nerve transfers were successful and functional analyses showed a maximum tetanic muscle force of 2.47 + 0.25 N after an ulnar nerve transfer. Deep branch transfers achieved 1.96 + 0.65 N, and neonates achieved 1.1 + 0.23 N. Control side was 2.78 + 0.24 N. The muscle weight was 325.6 + 0.24 mg for the control, 313.8 + 0.25 mg after UN transfer, 226.7 + 0.65 mg after deep branch transfer and 85.5 + 0.23 mg for neonates., Discussion: For proper clinical translation, an upper extremity model is needed. Successful reinnervation in all groups was demonstrated, which indicates an excellent model for future research. Variations in functional parameters are likely the effect of different donor axon ratios. Neuronal plasticity also appears to play a major role in the regeneration potential., Conclusion: This work illustrates several animal models to further investigate nerve transfers on all levels of the motor unit., Competing Interests: Die Autoren geben an, dass kein Interessenkonflikt besteht., (© Georg Thieme Verlag KG Stuttgart · New York.)

Targeted muscle reinnervation (TMR) amplifies the electrical activity of nerves at the stump of amputees by redirecting them in remnant muscles above the amputation. The electrical activity of the reinnervated muscles can be used to extract natural control signals. Nonetheless, current control systems, mainly based on noninvasive muscle recordings, fail to provide accurate and reliable control over time. This is one of the major reasons for prosthetic abandonment. This prospective interventional study includes three unilateral above-elbow amputees and reports the long-term (2.5 years) implant of wireless myoelectric sensors in the reinnervation sites after TMR and their use for control of robotic arms in daily life. It therefore demonstrates the clinical viability of chronically implanted myoelectric interfaces that amplify nerve activity through TMR. The patients showed substantial functional improvements using the implanted system compared with control based on surface electrodes. The combination of TMR and chronically implanted sensors may drastically improve robotic limb replacement in above-elbow amputees., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Iron based shape memory alloys (Fe-SMA) have recently been used as active flexural strengthening material for reinforced concrete (RC) beams. Fe-SMAs are characterized by a shape memory effect (SME) which allows the recovery of previously induced plastic deformations through heating. If these deformations are restrained a recovery stress is generated by the SME. This recovery stress can be used to prestress a SMA applied as a strengthening material. This paper investigates the performance and the load deformation behavior of RC beams strengthened with mechanical end anchored unbonded Fe-SMA strips activated by sequentially infrared heating. The performance of a single loop loaded and a double loop loaded SMA strengthened RC beam are compared to an un-strengthened beam and a reference beam strengthened with commercially available structural steel. In these tests the SMA strengthened beam had the highest cracking load and the highest ultimate load. It is shown that the serviceability behavior of a concrete beam can be improved by a second thermal activation. The sequential heating procedure causes different temperature and stress states during activation along the SMA strip that have not been researched previously. The possible effect of this different temperature and stress states on metal lattice phase transformation is modeled and discussed. Moreover the role of the martensitic transformation during the cooling process on leveling the inhomogeneity of phase state in the overheated section is pointed out., Competing Interests: The authors declare no conflict of interest. The founding sponsors had a role in the design of the study. They had no role in the collection, analyses, or interpretation of data and in the decision to publish the results.

Aims: Reconstruction of breasts and chest wall deformities in female patients after severe burn injury is a challenge for reconstructive surgeons. In these patients, neither implant-based procedures nor standard free flaps are sometimes applicable because of limited skin quality and unavailability of donor sites at the abdomen, back, buttock, or medial thigh., Methods: We present a case of a young female patient with a history of 80 % total body surface area burn after electric high-voltage injury. The burn occurred at the age of 9 years, and during the initial treatment, the right breast required amputation because of deep, full-thickness burn. Because the rigid and instable scar including chronic wound developed and an implant-based breast reconstruction was not feasible, the choice of possible free flaps was limited to the right lateral/proximal thigh. Preoperative computed tomography angiography demonstrated 2 intact perforators branching off the lateral femoral circumflex artery and a combined 17 × 24-cm tensor fascia lata/anterior lateral thigh perforator flap with in-flap anastomosis was transferred to the right breast after wound debridement and histological exclusion of Majolin ulcer in the instable scar. The internal mammary vessels were chosen as recipient vessels, and the donor site was covered with a split-thickness skin graft., Results: The postoperative course was uneventful at the right breast; however, the recipient site healed secondarily at the proximal pole. The resulting breast asymmetry was corrected by lipofilling of the central zone of the reconstructed breast and new definition of the inframammary fold as well as a minor liposuction at the cranial margin of the flap. The patient was very satisfied with the result, and no further correction was necessary., Conclusions: Autologous breast reconstruction is a valuable option for patients after severe burn injury. However, microsurgical expertise and an individualized and flexible surgical strategy are required for optimal reconstructive results. Computed tomography angiography is helpful for preoperative planning of the procedure.

During the last years, the prosthetic replacement in upper limb amputees has undergone different developments. The use of new nerve surgical concepts improved the control strategies tremendously, especially for high-level amputees. Technological innovation in the field of pattern recognition enables the control of multifunctional myoelectric hand prostheses in a natural and intuitive manner. However, the different levels of amputation pose different challenges for the therapeutic team which concern not only the prosthetic attachment; also the expected functional outcome of prosthetic limb replacement differs greatly between the individual levels of amputation. Therefore, especially in partial hand amputations the indication for prosthetic fitting has to be evaluated critically, as these patients may benefit more from biologic reconstructive concepts. The value of the upper extremity, in particular of the hand, is undisputable and, as such represents the driving force for the technological and surgical developments within the exoprosthetic replacement. This article discusses the possibilities and limitations of exoprosthetic limb replacement on the different amputation levels and explores new developments., (Georg Thieme Verlag KG Stuttgart · New York.)

Background: Prosthetic replacement after amputation or loss of function of the upper extremity has gained therapeutic value over the last years. The control of upper arm prostheses has been refined by the use of selective nerve transfers, and the indication for prosthetic replacement has been expanded., Objectives: Overview regarding surgical, therapeutic and prosthetic options in upper extremity amputations or their loss of function., Methods: Selective literature research including the authors' own experience in everyday clinical practice, as well as a review of medical records., Results: Selective nerve transfers of the amputated nerves of the brachial plexus to the remaining stump muscles can create up to six myosignals for intuitive and simultaneous control of the different prosthetic joints. This way, an efficient and harmonious control of the prosthetic device is possible without the need to change between the different control levels. The prosthetic replacement, with consequent elective amputation, represents a new approach in the functional reconstruction of the upper extremity, especially in patients with a functionless hand after massive soft tissue or nerve damage.

Animal research is debated highly controversial, as evident by the "Stop Vivi-section" initiative in 2015. Despite widespread protest to the initiative by researchers, no data is available on the European medical research community's opinion towards animal research. In this single-center study, we investigated this question in a survey of students and staff members at the Medical University of Vienna. A total of 906 participants responded to the survey, of which 82.8% rated the relevance of animal research high and 62% would not accept a treatment without prior animals testing. Overall, animal research was considered important, but its communication to the public considered requiring improvement.

Animal research is debated highly controversial, as evident by the "Stop Vivi-section" initiative in 2015. Despite widespread protest to the initiative by researchers, no data is available on the European medical research community's opinion towards animal research. In this single-center study, we investigated this question in a survey of students and staff members at the Medical University of Vienna. A total of 906 participants responded to the survey, of which 82.8% rated the relevance of animal research high and 62% would not accept a treatment without prior animals testing. Overall, animal research was considered important, but its communication to the public considered requiring improvement.

Mutilated hands at the distal level may pose a challenge for reconstruction. Biological treatment options may require multiple surgical interventions and a long rehabilitation course with little hope of good functional outcome. Standard hand prostheses are also not an ideal solution, as they are too long and cumbersome for partial hand injuries. This paper outlines the functional outcomes of prosthetic reconstruction with devices customized for the transcarpal amputation levels. The functional outcome was evaluated with the Action Research Arm Test (ARAT), Southampton Hand Assessment Procedure (SHAP), and the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH). Functional evaluation was performed at least 12 months after final fitting. Psychological assessment was performed with the Short Form-36. The three patients achieved a mean ARAT score of 35.67 ± 0.58. The average SHAP score was 74 ± 7.81. The average DASH score was found to be 16.11 ± 12.03. The reconstructed hand achieved a score of 75.27 ± 8.16% in SHAP and 62.57 ± 1.02% in ARAT in relation to the healthy hand. All patients exhibited average physical and mental component summary scales in the Short Form-36. The majority of transcarpal amputations are seen in manual laborers due to work-related trauma. Returning to work is the main goal in such young and otherwise-healthy patients. As shown with this study, prosthetic fitting results in quick and reliable functional reconstruction. Therefore, this treatment should be considered as an option during the initial decision-making process of reconstructing difficult traumatic injuries of the hand., (Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.)

Background: Nerve transfers are a powerful tool in extremity reconstruction, but the neurophysiological effects have not been adequately investigated. As 81 % of nerve injuries and most nerve transfers occur in the upper extremity with its own neurophysiological properties, the standard rat hindlimb model may not be optimal in this paradigm. Here we present an experimental rat forelimb model to investigate nerve transfers., Methods: In ten male Sprague-Dawley rats, the ulnar nerve was transferred to the motor branch of long head of the biceps. Sham surgery was performed in five animals (exposure/closure). After 12 weeks of regeneration, muscle force and Bertelli test were performed and evaluated., Results: The nerve transfer successfully reinnervated the long head of the biceps in all animals, as indicated by muscle force and behavioral outcome. No aberrant reinnervation occurred from the original motor source. Muscle force was 2,68 N ± 0.35 for the nerve transfer group and 2,85 N ± 0.39 for the sham group, which was not statically different ( p  = 0.436). The procedure led to minor functional deficits due to the loss of ulnar nerve function; this, however, could not be quantified with any of the presented measures., Conclusion: The above-described rat model demonstrated a constant anatomy, suitable for nerve transfers that are accessible to standard neuromuscular analyses and behavioral testing. This model allows the study of both neurophysiologic properties and cognitive motor function after nerve transfers in the upper extremity., Competing Interests: We, the authors, declare that we have no commercial association that might pose a conflict of interest in connection with the submitted article. We hereby disclose any financial and personal relationship with other people and organizations that could have influenced our work.

Background: Conventional upper arm prostheses are controlled via two surface electrodes that measure motor activity of two separately innervated muscle groups. The various prosthetic joints are chosen by co-contractions and controlled linearly by these two muscles. A harmonious and natural course of movements is not possible in this way., Objectives: Overview regarding surgical, therapeutical and prosthetic options in high amputations of the upper extremity., Methods: Selective literature research including the authors' own experience in everyday clinical practice as well as a review of medical records., Results: Selective nerve transfers of the amputated nerves of the brachial plexus to the remaining stump muscles can create up to six myosignals for intuitive and simultaneous control of the different prosthetic joints. In this way, an efficient and harmonious control of the prosthetic device is possible without the need to change between the different control levels. At the same time, possible neuromas are treated and painless wear of the prosthesis is achieved. Due to the resulting extended use of the prosthetic device, the demands regarding stump quality are increased. Thus, both surgically and by the means of the orthopedic technician a stable stump-socket connection should be achieved to enable optimal prosthetic function.

Background: Exposure of mesothelial cells to peritoneal dialysis fluids (PDF) results in cytoprotective cellular stress responses (CSR) that counteract PDF-induced damage. In this study, we tested the hypothesis that the CSR may be inadequate in relevant models of peritoneal dialysis (PD) due to insufficient levels of glutamine, resulting in increased vulnerability against PDF cytotoxicity. We particularly investigated the role of alanyl-glutamine (Ala-Gln) dipeptide on the cytoprotective PDF stress proteome., Methods: Adequacy of CSR was investigated in two human in vitro models (immortalized cell line MeT-5A and mesothelial cells derived from peritoneal effluent of uraemic patients) following exposure to heat-sterilized glucose-based PDF (PD4-Dianeal, Baxter) diluted with medium and, in a comparative proteomics approach, at different levels of glutamine ranging from depletion (0 mM) via physiological (0.7 mM) to pharmacological levels (8 mM administered as Ala-Gln)., Results: Despite severe cellular injury, expression of cytoprotective proteins was dampened upon PDF exposure at physiological glutamine levels, indicating an inadequate CSR. Depletion of glutamine aggravated cell injury and further reduced the CSR, whereas addition of Ala-Gln at pharmacological level restored an adequate CSR, decreasing cellular damage in both PDF exposure systems. Ala-Gln specifically stimulated chaperoning activity, and cytoprotective processes were markedly enhanced in the PDF stress proteome., Conclusions: Taken together, this study demonstrates an inadequate CSR of mesothelial cells following PDF exposure associated with low and physiological levels of glutamine, indicating a new and potentially relevant pathomechanism. Supplementation of PDF with pharmacological doses of Ala-Gln restored the cytoprotective stress proteome, resulting in improved resistance of mesothelial cells to exposure to PDF. Future work will study the clinical relevance of CSR-mediated cytoprotection.