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Topley M, Crotty AM, Boyle A, Peller J, Kawaja M, Hendry JM. Evaluation of motor and sensory neuron populations in a mouse median nerve injury model. J Neurosci Methods 2023; 396:109937. [PMID: 37531978 DOI: 10.1016/j.jneumeth.2023.109937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 07/23/2023] [Accepted: 07/29/2023] [Indexed: 08/04/2023]
Abstract
BACKGROUND Peripheral nerves can regenerate and restore function after injury but this process is hindered by many factors including chronic denervation, motor end-plate resorption and Schwann cell senescence. Forelimb injury models in rodents are becoming increasingly popular as they more accurately reflect the physiology and biomechanics of upper extremity nerve injuries. However several aspects of this surgical model remain poorly characterized. NEW METHOD C57Bl/6 mice underwent enumeration of median nerve motor and sensory neuron pools using retrograde labeling with or without nerve transection. Distal histomorphometry of uninjured mouse median nerves was also examined. Baseline reference values of volitional forelimb grip strength measurements were determined and the rate of neural elongation was also estimated. RESULTS We identified 1363 ± 165 sensory and 216 ± 16 motor neurons within the uninjured dorsal root ganglia (DRG) and ventral spinal cord, respectively. Eight days following injury, approximately 34% of motoneurons had elongated a distance of 5 mm beyond the repair site 8 days following injury. Volitional grip strength decreased 50% with unilateral median nerve transection and was negligible with contralateral flexor tendon tenotomy. COMPARISON WITH EXISTING METHOD Our spinal cord and DRG harvesting technique presented here was technically straightforward and reliable. Estimates of motor and sensory neuron numbers for the mouse median nerve compared favourably with studies using intramuscular injection of retrograde neurotracer. Histomorphometry data was consistent with and reinforced reference values in the literature. CONCLUSIONS This study provides data that further develops an increasingly popular surgical model for studying peripheral nerve injury and repair.
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Affiliation(s)
- Max Topley
- Department of Surgery, Queen's University, Kingston, ON, Canada; Centre for Neuroscience Studies, Queen's University, Canada
| | - Anne-Marie Crotty
- Department of Surgery, Queen's University, Kingston, ON, Canada; Centre for Neuroscience Studies, Queen's University, Canada
| | - Amy Boyle
- Centre for Neuroscience Studies, Queen's University, Canada
| | - Jacob Peller
- Centre for Neuroscience Studies, Queen's University, Canada
| | - Michael Kawaja
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada; Centre for Neuroscience Studies, Queen's University, Canada
| | - J Michael Hendry
- Department of Surgery, Queen's University, Kingston, ON, Canada; Kingston Health Sciences Center, Kingston, ON, Canada; Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada; Centre for Neuroscience Studies, Queen's University, Canada.
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2
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Luft M, Klepetko J, Muceli S, Ibáñez J, Tereshenko V, Festin C, Laengle G, Politikou O, Maierhofer U, Farina D, Aszmann OC, Bergmeister KD. Proof of concept for multiple nerve transfers to a single target muscle. eLife 2021; 10:71312. [PMID: 34596042 PMCID: PMC8530510 DOI: 10.7554/elife.71312] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 09/30/2021] [Indexed: 11/13/2022] Open
Abstract
Surgical nerve transfers are used to efficiently treat peripheral nerve injuries, neuromas, phantom limb pain, or improve bionic prosthetic control. Commonly, one donor nerve is transferred to one target muscle. However, the transfer of multiple nerves onto a single target muscle may increase the number of muscle signals for myoelectric prosthetic control and facilitate the treatment of multiple neuromas. Currently, no experimental models are available. This study describes a novel experimental model to investigate the neurophysiological effects of peripheral double nerve transfers to a common target muscle. In 62 male Sprague-Dawley rats, the ulnar nerve of the antebrachium alone (n=30) or together with the anterior interosseus nerve (n=32) was transferred to reinnervate the long head of the biceps brachii. Before neurotization, the motor branch to the biceps’ long head was transected at the motor entry point. Twelve weeks after surgery, muscle response to neurotomy, behavioral testing, retrograde labeling, and structural analyses were performed to assess reinnervation. These analyses indicated that all nerves successfully reinnervated the target muscle. No aberrant reinnervation was observed by the originally innervating nerve. Our observations suggest a minimal burden for the animal with no signs of functional deficit in daily activities or auto-mutilation in both procedures. Furthermore, standard neurophysiological analyses for nerve and muscle regeneration were applicable. This newly developed nerve transfer model allows for the reliable and standardized investigation of neural and functional changes following the transfer of multiple donor nerves to one target muscle.
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Affiliation(s)
- Matthias Luft
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Vienna, Vienna, Austria.,Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Johanna Klepetko
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Vienna, Vienna, Austria.,Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Silvia Muceli
- Department of Electrical Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Jaime Ibáñez
- Department of Bioengineering, Imperial College London, London, United Kingdom.,Department of Clinical and Movement Neuroscience, University College London, London, London, United Kingdom.,BSICoS Group, IIS Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Vlad Tereshenko
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Vienna, Vienna, Austria.,Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Christopher Festin
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Vienna, Vienna, Austria.,Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Gregor Laengle
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Vienna, Vienna, Austria.,Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Olga Politikou
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Vienna, Vienna, Austria.,Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Udo Maierhofer
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Vienna, Vienna, Austria.,Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Dario Farina
- Department of Bioengineering, Imperial College London, London, United Kingdom.,Department of Clinical and Movement Neuroscience, University College London, London, London, United Kingdom
| | - Oskar C Aszmann
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Vienna, Vienna, Austria.,Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Vienna, Vienna, Austria
| | - Konstantin Davide Bergmeister
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Vienna, Vienna, Austria.,Center for Biomedical Research, Medical University of Vienna, Vienna, Austria.,Karl Landsteiner University of Health Sciences, Department of Plastic, Aesthetic and ReconstructiveSurgery, University Hospital St. Poelten, St. Poelten, Austria
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3
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Sporer ME, Aman M, Bergmeister KD, Depisch D, Scheuba KM, Unger E, Podesser BK, Aszmann OC. Experimental nerve transfer model in the neonatal rat. Neural Regen Res 2021; 17:1088-1095. [PMID: 34558537 PMCID: PMC8552847 DOI: 10.4103/1673-5374.324851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Clinically, peripheral nerve reconstructions in neonates are most frequently applied in brachial plexus birth injuries. Most surgical concepts, however, have investigated nerve reconstructions in adult animal models. The immature neuromuscular system reacts differently to the effects of nerve lesion and surgery and is poorly investigated due to the lack of reliable experimental models. Here, we describe an experimental forelimb model in the neonatal rat, to study these effects on both the peripheral and central nervous systems. Within 24 hours after birth, three groups were prepared: In the nerve transfer group, a lesion of the musculocutaneous nerve was reconstructed by selectively transferring the ulnar nerve. In the negative control group, the musculocutaneous nerve was divided and not reconstructed and in the positive control group, a sham surgery was performed. The animal´s ability to adapt to nerve lesions and progressive improvement over time were depict by the Bertelli test, which observes the development of grooming. Twelve weeks postoperatively, animals were fully matured and the nerve transfer successfully reinnervated their target muscles, which was indicated by muscle force, muscle weight, and cross sectional area evaluation. On the contrary, no spontaneous regeneration was found in the negative control group. In the positive control group, reference values were established. Retrograde labeling indicated that the motoneuron pool of the ulnar nerve was reduced following nerve transfer. Due to this post-axotomy motoneuron death, a diminished amount of motoneurons reinnervated the biceps muscle in the nerve transfer group, when compared to the native motoneuron pool of the musculocutaneous nerve. These findings indicate that the immature neuromuscular system behaves profoundly different than similar lesions in adult rats and explains reduced muscle force. Ultimately, pathophysiologic adaptations are inevitable. The maturing neuromuscular system, however, utilizes neonatal capacity of regeneration and seizes a variety of compensation mechanism to restore a functional extremity. The above described neonatal rat model demonstrates a constant anatomy, suitable for nerve transfers and allows all standard neuromuscular analyses. Hence, detailed investigations on the pathophysiological changes and subsequent effects of trauma on the various levels within the neuromuscular system as well as neural reorganization of the neonatal rat may be elucidated. This study was approved by the Ethics Committee of the Medical University of Vienna and the Austrian Ministry for Research and Science (BMWF-66.009/0187-WF/V/3b/2015) on March 20, 2015.
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Affiliation(s)
- Matthias E Sporer
- Christian Doppler Laboratory for the Restoration of Extremity Function; Clinical Laboratory for Bionic Extremity Reconstruction, Department of Surgery, Medical University of Vienna, Vienna, Austria; Division of Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Martin Aman
- Christian Doppler Laboratory for the Restoration of Extremity Function, Department of Surgery; Division of Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Konstantin D Bergmeister
- Christian Doppler Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of Vienna, Vienna; Department of Plastic, Aesthetic and Reconstructive Surgery, University Hospital of St. Poelten, Karl Landsteiner University of Health Sciences, St. Poelten, Austria
| | - Dieter Depisch
- Christian Doppler Laboratory for the Restoration of Extremity Function; Clinical Laboratory for Bionic Extremity Reconstruction, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Katharina M Scheuba
- Christian Doppler Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Ewald Unger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Bruno K Podesser
- Division of Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Oskar C Aszmann
- Christian Doppler Laboratory for the Restoration of Extremity Function; Clinical Laboratory for Bionic Extremity Reconstruction, Department of Surgery; Division of Plastic and Reconstructive Surgery, Medical University of Vienna, Vienna, Austria
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4
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Li A, Pereira C, Hill EE, Vukcevich O, Wang A. In vitro, In vivo and Ex vivo Models for Peripheral Nerve Injury and Regeneration. Curr Neuropharmacol 2021; 20:344-361. [PMID: 33827409 PMCID: PMC9413794 DOI: 10.2174/1570159x19666210407155543] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 01/29/2021] [Accepted: 03/29/2021] [Indexed: 11/22/2022] Open
Abstract
Peripheral Nerve Injuries (PNI) frequently occur secondary to traumatic injuries. Recovery from these injuries can be expectedly poor, especially in proximal injuries. In order to study and improve peripheral nerve regeneration, scientists rely on peripheral nerve models to identify and test therapeutic interventions. In this review, we discuss the best described and most commonly used peripheral nerve models that scientists have and continue to use to study peripheral nerve physiology and function.
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Affiliation(s)
- Andrew Li
- University of California Davis Ringgold standard institution - Hand and Upper Extremity Surgery, Division of Plastic Surgery, Department of Surgery Sacramento, California. United States
| | - Clifford Pereira
- University of California Davis Ringgold standard institution - Hand and Upper Extremity Surgery, Division of Plastic Surgery, Department of Surgery Sacramento, California. United States
| | - Elise Eleanor Hill
- University of California Davis Ringgold standard institution - Department of Surgery Sacramento, California. United States
| | - Olivia Vukcevich
- University of California Davis Ringgold standard institution - Surgery & Biomedical Engineering Sacramento, California. United States
| | - Aijun Wang
- University of California Davis - Surgery & Biomedical Engineering 4625 2nd Ave., Suite 3005 Sacramento Sacramento California 95817. United States
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5
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Aman M, Bergmeister KD, Festin C, Sporer ME, Russold MF, Gstoettner C, Podesser BK, Gail A, Farina D, Cederna P, Aszmann OC. Experimental Testing of Bionic Peripheral Nerve and Muscle Interfaces: Animal Model Considerations. Front Neurosci 2020; 13:1442. [PMID: 32116485 PMCID: PMC7025572 DOI: 10.3389/fnins.2019.01442] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 12/23/2019] [Indexed: 12/05/2022] Open
Abstract
Introduction: Man-machine interfacing remains the main challenge for accurate and reliable control of bionic prostheses. Implantable electrodes in nerves and muscles may overcome some of the limitations by significantly increasing the interface's reliability and bandwidth. Before human application, experimental preclinical testing is essential to assess chronic in-vivo biocompatibility and functionality. Here, we analyze available animal models, their costs and ethical challenges in special regards to simulating a potentially life-long application in a short period of time and in non-biped animals. Methods: We performed a literature analysis following the PRISMA guidelines including all animal models used to record neural or muscular activity via implantable electrodes, evaluating animal models, group size, duration, origin of publication as well as type of interface. Furthermore, behavioral, ethical, and economic considerations of these models were analyzed. Additionally, we discuss experience and surgical approaches with rat, sheep, and primate models and an approach for international standardized testing. Results: Overall, 343 studies matched the search terms, dominantly originating from the US (55%) and Europe (34%), using mainly small animal models (rat: 40%). Electrode placement was dominantly neural (77%) compared to muscular (23%). Large animal models had a mean duration of 135 ± 87.2 days, with a mean of 5.3 ± 3.4 animals per trial. Small animal models had a mean duration of 85 ± 11.2 days, with a mean of 12.4 ± 1.7 animals. Discussion: Only 37% animal models were by definition chronic tests (>3 months) and thus potentially provide information on long-term performance. Costs for large animals were up to 45 times higher than small animals. However, costs are relatively small compared to complication costs in human long-term applications. Overall, we believe a combination of small animals for preliminary primary electrode testing and large animals to investigate long-term biocompatibility, impedance, and tissue regeneration parameters provides sufficient data to ensure long-term human applications.
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Affiliation(s)
- Martin Aman
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Surgery, Medical University of Vienna, Vienna, Austria.,Division of Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Konstantin D Bergmeister
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Surgery, Medical University of Vienna, Vienna, Austria.,Division of Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Christopher Festin
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Matthias E Sporer
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Surgery, Medical University of Vienna, Vienna, Austria.,Division of Biomedical Research, Medical University of Vienna, Vienna, Austria
| | | | - Clemens Gstoettner
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Bruno K Podesser
- Division of Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Alexander Gail
- Cognitive Neuroscience Lab, German Primate Center, Göttingen, Germany
| | - Dario Farina
- Department of Bioengineering, Imperial College, London, United Kingdom
| | - Paul Cederna
- Section of Plastic and Reconstructive Surgery, Department of Surgery, University of Michigan, Ann Arbor, MI, United States
| | - Oskar C Aszmann
- Clinical Laboratory for Bionic Extremity Reconstruction, Department of Surgery, Medical University of Vienna, Vienna, Austria.,Division of Plastic and Reconstructive Surgery, Medical University of Vienna, Vienna, Austria
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6
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Bergmeister KD, Aman M, Muceli S, Vujaklija I, Manzano-Szalai K, Unger E, Byrne RA, Scheinecker C, Riedl O, Salminger S, Frommlet F, Borschel GH, Farina D, Aszmann OC. Peripheral nerve transfers change target muscle structure and function. SCIENCE ADVANCES 2019; 5:eaau2956. [PMID: 30613770 PMCID: PMC6314825 DOI: 10.1126/sciadv.aau2956] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Accepted: 11/26/2018] [Indexed: 05/05/2023]
Abstract
Selective nerve transfers surgically rewire motor neurons and are used in extremity reconstruction to restore muscle function or to facilitate intuitive prosthetic control. We investigated the neurophysiological effects of rewiring motor axons originating from spinal motor neuron pools into target muscles with lower innervation ratio in a rat model. Following reinnervation, the target muscle's force regenerated almost completely, with the motor unit population increasing to 116% in functional and 172% in histological assessments with subsequently smaller muscle units. Muscle fiber type populations transformed into the donor nerve's original muscles. We thus demonstrate that axons of alternative spinal origin can hyper-reinnervate target muscles without loss of muscle force regeneration, but with a donor-specific shift in muscle fiber type. These results explain the excellent clinical outcomes following nerve transfers in neuromuscular reconstruction. They indicate that reinnervated muscles can provide an accurate bioscreen to display neural information of lost body parts for high-fidelity prosthetic control.
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Affiliation(s)
- Konstantin D. Bergmeister
- CD Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of Vienna, Vienna, Austria
- Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Martin Aman
- CD Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of Vienna, Vienna, Austria
- Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Silvia Muceli
- Department of Bioengineering, Imperial College London, London, UK
- Clinic for Trauma Surgery, Orthopaedic Surgery and Plastic Surgery–Research Department of Neurorehabilitation Systems, University Medical Center Göttingen, Göttingen, Germany
| | - Ivan Vujaklija
- Department of Bioengineering, Imperial College London, London, UK
| | - Krisztina Manzano-Szalai
- CD Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Ewald Unger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Ruth A. Byrne
- Division of Rheumatology, Clinic for Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Clemens Scheinecker
- Division of Rheumatology, Clinic for Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Otto Riedl
- CD Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Stefan Salminger
- CD Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of Vienna, Vienna, Austria
- Division of Plastic and Reconstructive Surgery, Medical University of Vienna, Vienna, Austria
| | - Florian Frommlet
- Center for Medical Statistics, Informatics and Intelligent Systems, Section for Medical Statistics, Medical University of Vienna, Vienna, Austria
| | - Gregory H. Borschel
- Division of Plastic and Reconstructive Surgery, The Hospital for Sick Children, Toronto, ON, Canada
| | - Dario Farina
- Department of Bioengineering, Imperial College London, London, UK
| | - Oskar C. Aszmann
- CD Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of Vienna, Vienna, Austria
- Division of Plastic and Reconstructive Surgery, Medical University of Vienna, Vienna, Austria
- Corresponding author.
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7
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Muceli S, Bergmeister KD, Hoffmann KP, Aman M, Vukajlija I, Aszmann OC, Farina D. Decoding motor neuron activity from epimysial thin-film electrode recordings following targeted muscle reinnervation. J Neural Eng 2018; 16:016010. [PMID: 30524045 DOI: 10.1088/1741-2552/aaed85] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Surface electromyography (EMG) is currently used as a control signal for active prostheses in amputees who underwent targeted muscle reinnervation (TMR) surgery. Recent research has shown that it is possible to access the spiking activity of spinal motor neurons from multi-channel surface EMG. In this study, we propose the use of multi-channel epimysial EMG electrodes as an interface for decoding motor neurons activity following TMR. APPROACH We tested multi-channel epimysial electrodes (48 detection sites) built with thin-film technology in an animal model of TMR. Eight animals were tested 12 weeks after reinnervation of the biceps brachii lateral head by the ulnar nerve. We identified the position of the innervation zone and the muscle fiber conduction velocity of motor units decoded from the multi-channel epimysial recordings. Moreover, we characterized the pick-up volume by the distribution of the motor unit action potential amplitude over the epimysium surface. MAIN RESULTS The electrodes provided high quality signals with average signal-to-noise ratio >30 dB across 95 identified motor units. The motor unit action potential amplitude decreased with increasing distance of the electrode from the muscle fibers (P [Formula: see text] 0.001). The decrease was more pronounced for bipolar compared to monopolar derivations. The average muscle fiber conduction velocity was 2.46 ± 0.83 m s-1. Most of the neuromuscular junctions were close to the region where the nerve was neurotized, as observed from the EMG recordings and imaging data. SIGNIFICANCE These results show that epimysial electrodes can be used for selective recordings of motor unit activities with a pick-up volume that included the entire muscle in the rat hindlimb. Epimysial electrodes can thus be used for detecting motor unit activity in muscles with specific fascicular territories associated to different functions following TMR surgery.
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Affiliation(s)
- Silvia Muceli
- Department of Bioengineering, Imperial College London, London, United Kingdom
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8
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Bergmeister KD, Vujaklija I, Muceli S, Sturma A, Hruby LA, Prahm C, Riedl O, Salminger S, Manzano-Szalai K, Aman M, Russold MF, Hofer C, Principe J, Farina D, Aszmann OC. Broadband Prosthetic Interfaces: Combining Nerve Transfers and Implantable Multichannel EMG Technology to Decode Spinal Motor Neuron Activity. Front Neurosci 2017; 11:421. [PMID: 28769755 PMCID: PMC5515902 DOI: 10.3389/fnins.2017.00421] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Accepted: 07/05/2017] [Indexed: 01/09/2023] Open
Abstract
Modern robotic hands/upper limbs may replace multiple degrees of freedom of extremity function. However, their intuitive use requires a high number of control signals, which current man-machine interfaces do not provide. Here, we discuss a broadband control interface that combines targeted muscle reinnervation, implantable multichannel electromyographic sensors, and advanced decoding to address the increasing capabilities of modern robotic limbs. With targeted muscle reinnervation, nerves that have lost their targets due to an amputation are surgically transferred to residual stump muscles to increase the number of intuitive prosthetic control signals. This surgery re-establishes a nerve-muscle connection that is used for sensing nerve activity with myoelectric interfaces. Moreover, the nerve transfer determines neurophysiological effects, such as muscular hyper-reinnervation and cortical reafferentation that can be exploited by the myoelectric interface. Modern implantable multichannel EMG sensors provide signals from which it is possible to disentangle the behavior of single motor neurons. Recent studies have shown that the neural drive to muscles can be decoded from these signals and thereby the user's intention can be reliably estimated. By combining these concepts in chronic implants and embedded electronics, we believe that it is in principle possible to establish a broadband man-machine interface, with specific applications in prosthesis control. This perspective illustrates this concept, based on combining advanced surgical techniques with recording hardware and processing algorithms. Here we describe the scientific evidence for this concept, current state of investigations, challenges, and alternative approaches to improve current prosthetic interfaces.
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Affiliation(s)
- Konstantin D. Bergmeister
- CD-Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of ViennaVienna, Austria
- Department of Hand, Plastic and Reconstructive Surgery, Burn Center, BG Trauma Center Ludwigshafen, Plastic and Hand Surgery, University of HeidelbergLudwigshafen, Germany
| | - Ivan Vujaklija
- Department of Bioengineering, Centre for Neurotechnology, Imperial College LondonLondon, United Kingdom
| | - Silvia Muceli
- Neurorehabilitation Systems Research Group, Clinic for Trauma Surgery, Orthopedics and Plastic Surgery, University Medical Center GöttingenGöttingen, Germany
| | - Agnes Sturma
- CD-Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of ViennaVienna, Austria
- Health Assisting Engineering, University of Applied Sciences WienVienna, Austria
| | - Laura A. Hruby
- CD-Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of ViennaVienna, Austria
| | - Cosima Prahm
- CD-Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of ViennaVienna, Austria
| | - Otto Riedl
- CD-Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of ViennaVienna, Austria
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Medical University of ViennaVienna, Austria
| | - Stefan Salminger
- CD-Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of ViennaVienna, Austria
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Medical University of ViennaVienna, Austria
| | - Krisztina Manzano-Szalai
- CD-Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of ViennaVienna, Austria
| | - Martin Aman
- CD-Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of ViennaVienna, Austria
| | | | - Christian Hofer
- CD-Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of ViennaVienna, Austria
- Otto Bock Healthcare Products GmbHVienna, Austria
| | - Jose Principe
- Department of Electrical and Computer Engineering, University of FloridaGainesville, FL, United States
| | - Dario Farina
- Department of Bioengineering, Centre for Neurotechnology, Imperial College LondonLondon, United Kingdom
| | - Oskar C. Aszmann
- CD-Laboratory for the Restoration of Extremity Function, Department of Surgery, Medical University of ViennaVienna, Austria
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Medical University of ViennaVienna, Austria
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