{"paper_id":"3b9db7eb-e4b9-46cb-a1ff-1c57b215abe5","body_text":"Time Zero Gap Created by Rat Sciatic Nerve Transection | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Time Zero Gap Created by Rat Sciatic Nerve Transection Elan Shukhmakher, Yelena Akelina, Robert J. Strauch This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6590688/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 11 You are reading this latest preprint version Abstract Background Gaps following traumatic nerve transection can be overcome by nerve mobilization or by nerve grafting. Excessive tension across a nerve repair is thought to be detrimental to nerve healing leading many surgeons to perform nerve grafting in the setting of even modest tension across a nerve repair. Fresh nerve transections typically result in a nerve gap from the elastic recoil of the nerve itself. The size of the nerve gap created by a fresh transection of the rat sciatic nerve has previously not been quantified. The goal of this study was to measure the acute nerve gap produced by rat sciatic nerve transection. Results The average rat sciatic nerve gap size following transection was 3.77mm, with a range of 2mm-6mm. The average nerve diameter was 1.82mm, with a range of 1.4mm-2.5mm. Conclusion Immediately following transection of the rat sciatic nerve, a gap equal to twice the diameter of the nerve is created. This gap is produced by the elastic recoil of the nerve. nerve gap transection rat sciatic nerve Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Background Traumatic nerve injuries can result in substantial disability [1]. Reports show instances of traumatic nerve injuries to be close to 350,000 cases per year, with the majority of those who suffered from such afflictions being young, having an average age of 32-39 [2]. Operative exploration of acutely transected nerves typically reveals some retraction of the nerve ends, known as the “nerve gap”. Mobilization of the nerve ends can often result in successful primary repair, however, if “excessive” tension exists at the repair site, a nerve graft may be more appropriate. Outcomes of nerve grafting are uniformly inferior to those of primary nerve repair [3], however the decision to perform nerve grafting as opposed to a primary repair is often a subjective one. What seems to be a ‘tight’ nerve repair can often be remedied by adequate nerve mobilization, moderate adjacent joint flexion, and ‘stress-relaxation’ by placing a few larger caliber sutures to take the tension off the repair and waiting a few minutes for the nerve to stretch out. With the increasing popularity of nerve allografting, it seems that fewer acutely transected nerves (within first two weeks of injury) are being repaired primarily owing to concerns of excessive tension at the repair site [4]. It has been widely anecdotally observed that even when a nerve is freshly cut, there is a substantial nerve gap immediately created by the inherent elastic recoil of the nerve. The goal of the present study was to quantify the size of the acute nerve gap produced by rat sciatic nerve transection. Methods Twenty-two live Sprague-Dawley male rats weighing ~300g were utilized for this study, allowing for 44 sciatic nerves to be dissected and transected by the same surgeon. All procedures received approval from the Columbia University Medical Center Institutional Animal Care and Use Committee. All surgical manipulations were conducted under an operating-microscope (Zeiss OPMIMD; Carl Zeiss; Jena, Germany). The rats were initially anesthetized via a 75-95mg/Kg ketamine and 5-8mg/Kg xylazine intraperitoneal injection, and an intraperitoneal bolus was used throughout the procedure to maintain anesthesia. All animals were shaved, scrubbed with povidone iodine and alcohol, and positioned prone. Masking tape and pins to secure the arms and legs of the rat to the operating board were used, followed by placing 5 4x4 gauze underneath the leg of the rat, depending on which side was being operated on. Using a scalpel with a #15 blade, along with Adson tissue forceps and cotton tip applicators, blunt dissection at muscle planes between quadriceps femoris and biceps femoris exposed the right and left sciatic nerves of each rodent [Figure 1]. 1cm of the bilateral sciatic nerves were carefully exposed and released from the surrounding tissues without injury to vessels or nerve branches [Figure 2]. The diameter of the sciatic nerve at the site of the planned transection was measured using a Shinwa Sokutei 58698 crack scale scientific ruler [Figure 3]. With a fresh scalpel, the sciatic nerves were transected using a wooden spatula beneath the nerve to protect the underlying tissue [Figure 4]. Measurements of the gap between the nerve ends were measured using the ruler. Upon completion of the surgical procedure and collection of data, the animals were euthanized with a 100mg/Kg Euthasol Intraperitoneal injection. The primary outcome measure was the measured gap in the sciatic nerve following transection. Results Twenty-two live Sprague-Dawley male rats were used as the eligible group in this study, resulting in 44 sciatic nerves being dissected, transected, and measured [Figure 5]. A mean nerve gap of 3.77mm was found with a range of 2mm to 6mm and a standard deviation of 1.06mm. The frequencies of the measured nerve gaps are shown in [Table 1]. The diameter of the sciatic nerves at the transection site was 1.82mm on average with a range of 1.4mm to 2.5mm and, a standard deviation of 0.27mm. The frequencies of the measured nerve diameters are shown in [Table 2]. Table 1 Frequencies of Nerve Gaps Nerve Gap (Millimeters) Frequency 2 6 (13.64%) 3 10 (22.73%) 3.5 4 (9.09%) 4 11 (25.00%) 4.5 1 (2.27%) 5 10 (22.73%) 5.5 1 (2.27%) 6 1 (2.27%) Frequencies of the nerve gap sizes observed, with 4mm representing the most frequent gap measured. Table 2 Frequencies of Nerve Diameters Nerve Diameter (Millimeters) Frequency 1.4 1 (2.27%) 1.5 5 (11.36%) 1.6 6 (13.64%) 1.7 12 (27.27%) 1.8 2 (4.55%) 1.9 4 (9.09%) 2.0 9 (20.45%) 2.2 2 (4.55%) 2.5 3 (6.82%) Frequencies of the nerve diameter sizes observed, with1.7mm representing the most frequent diameter measured. Discussion Treatment of chronic nerve lacerations involves trimming back the adjoining nerve ends to healthy fascicular patterns; this can result in substantial nerve gaps requiring some kind of bridging conduit, such as hollow tubes, allograft or autograft nerve interposition. In recent years, there has been increasing enthusiasm for repairing even acutely lacerated nerves with nerve allografts following the rationale that any tension on a nerve repair is detrimental to outcomes [4]. All acutely lacerated nerves will demonstrate some retraction of the ends, even seconds after the nerve is lacerated. When repairing recently lacerated nerves, the gap between the nerve ends caused by inherent elastic nerve recoil can typically be overcome by placing a few larger sutures and allowing the nerve to “stress-relax” to the point where a repair can be undertaken with fine sutures under less tension. Nevertheless, some practitioners suggest that even acutely sharply transected nerves be treated with interposition allograft repair, under the theory that any tension at the nerve repair site should be discouraged. The downside of interposition nerve grafting is that primary nerve repair under even moderate tension yields superior results to any interposition grafting procedure, even autografting [5] [6]. The basic science shows that acute significant stretching of a nerve is detrimental to nerve blood flow and thus healing [7], however substantial successful nerve elongation is possible over time, as occurs with limb or finger lengthening. Mackinnon has shown in a rat sciatic nerve model that acute nerve elongation to overcome a gap can be a problem, however if modest dissection and ‘freeing up’ of the nerve is performed, then tension at the nerve repair site is markedly diminished [8]. In one of the few basic science primate studies on nerve repair, Hentz et al repaired the ulnar nerves of Cynomolgus monkeys either primarily under tension or by using an interposition autograft under no tension and found better results in the nerves repaired under tension without the autograft. They concluded that for defects of up to 3-4 cm in adult humans that modest tension across the nerve repair site was superior to using an auto or other graft to achieve a tension free repair [3]. To the best of our knowledge, no data exists concerning the size of nerve gaps in acutely lacerated human nerves; such a study could be ethically performed examining gaps during intentional neurotomies associated with procedures such as denervations, nerve transfers or neuroma treatments. Therefore, this study has shown that at time zero an instantaneous gap is created by nerve transection owing to the inherent elastic recoil of the nerve itself. This gap, in the rat sciatic nerve model, is equivalent to twice the diameter of the nerve itself. If this were to be extrapolated to a human median nerve transection at the wrist, with a diameter of approximately 5 mm, this would be a 1 cm gap [9]. Clinically, we have observed gaps of over one cm in acutely lacerated median and ulnar nerves. The point of this study is to show that even at time zero, there exists a significant nerve gap produced by nerve transection. Such a gap is usually seen following nerve transection and should be recognized as a normal finding, not a pathological nerve gap that necessarily requires a nerve graft. This study is limited by examining only a single time point shortly following sciatic nerve transection. Although this allows for standardized measurement of the instantaneous gap, it does not take into account dynamic changes that may occur following injury, such as nerve retraction or early tissue remodeling. Although the rat sciatic nerve model is widely used for studies on peripheral nerves, anatomical and physiological differences in human and rat nervous systems can potentially hinder direct extrapolation. Nerve diameter, along with connective tissue and muscle composition surrounding the nerve, can influence gap development differently in human nerves and need to be considered while extrapolating the clinical relevance of results. Conclusion Nerve gaps measuring twice the diameter of the rat sciatic nerve are produced by acute nerve transection. This gap is likely related to the inherent elasticity of the nerve. Such acute nerve gaps will be easily overcome by primary nerve repair and typically will not require nerve auto or allografting. Declarations Ethics approval and consent to participate All procedures received approval from the Columbia University Medical Center Institutional Animal Care and Use Committee. Consent For Publication Not applicable Availability of data and materials All data generated or analyzed during this study are included in this published article [and its supplementary information files]. Funding Not applicable Authors contributions E.S - Contributed to this study by conducting the experimental procedure, collecting the data, assisting in data analysis, and being primarily responsible for writing the manuscript. Y.A- Contributed to the design of the experimental procedure, assisted in data analysis, and provided critical revisions and edits to the manuscript. R.S- Contributed to the design of the experimental procedure, assisted in data analysis, and provided critical revisions and edits to the manuscript. Acknowledgments Not applicable List of abbreviations Not applicable References Zhang S, Huang M, Zhi J, Wu S, Wang Y, Pei F. Research hotspots and trends of peripheral nerve injuries based on web of science from 2017 to 2021: A bibliometric analysis. Frontiers; 2022. Available from: https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2022.872261/full 1. Cruz AJM. Neurotmesis. U.S. National Library of Medicine; 2023. Available from: https://www.ncbi.nlm.nih.gov/books/NBK559108/ Hentz VR, Rosen JM, Xiao SJ, McGill KC, Abraham G. The nerve gap dilemma: A comparison of nerves repaired end to end under tension with nerve grafts in a primate model. U.S. National Library of Medicine; 1993. Available from: https://pubmed.ncbi.nlm.nih.gov/8515008/ Lans J, Eberlin K, Evans P, Mercer D, Greenberg J, Styron J. A systematic review and meta-analysis of Nerve Gap Repair: Comparative effectiveness of allografts, autografts, and Conduits. U.S. National Library of Medicine; 2022. Available from: https://pubmed.ncbi.nlm.nih.gov/36728885/ Murovic JA. Upper-extremity peripheral nerve injuries: A Louisiana State University Health Sciences Center Literature Review with comparison of the operative outcomes of 1837 Louisiana State University Health Sciences Center Median, radial, and ulnar nerve lesions. U.S. National Library of Medicine; 2009. Available from: https://pubmed.ncbi.nlm.nih.gov/19927055/ Sallam A, Eldeeb M, Kamel N. Autologous fibrin glue versus microsuture in the surgical reconstruction of peripheral nerves: A randomized clinical trial. U.S. National Library of Medicine; 2021. Available from: https://pubmed.ncbi.nlm.nih.gov/34011463/ Yi C, Dahlin L. Impaired nerve regeneration and Schwann cell activation after repair with tension. U.S. National Library of Medicine; 2010. Available from: https://pubmed.ncbi.nlm.nih.gov/20729767/ Sunderland I, Brenner M, Singham J, Rickman S, Hunter D, Mackinnon S. Effect of tension on nerve regeneration in rat sciatic nerve transection model. U.S. National Library of Medicine; [cited 2004 Oct]. Available from: https://pubmed.ncbi.nlm.nih.gov/15385776/ Ortiz R, Westenberg R, Langhammer C, Knaus W, Chen N, Eberlin K. Nerve diameter in the hand: A cadaveric study [Internet]. U.S. National Library of Medicine; 2019. Available from: https://pubmed.ncbi.nlm.nih.gov/31044121/ Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 04 Jun, 2025 Reviews received at journal 18 May, 2025 Reviewers agreed at journal 16 May, 2025 Reviews received at journal 14 May, 2025 Reviewers agreed at journal 14 May, 2025 Reviewers agreed at journal 14 May, 2025 Reviews received at journal 14 May, 2025 Reviewers agreed at journal 14 May, 2025 Reviewers invited by journal 14 May, 2025 Submission checks completed at journal 14 May, 2025 First submitted to journal 14 May, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {\"props\":{\"pageProps\":{\"initialData\":{\"identity\":\"rs-6590688\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":458296296,\"identity\":\"8d054200-fb9e-48b1-b4a9-6f3afa3c1e7d\",\"order_by\":0,\"name\":\"Elan Shukhmakher\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABDUlEQVRIiWNgGAWjYDACdiBmbGAwMGBgYGYGsuVAggce4NPCjKbFGKwlgRQtiQ0gUXxa+JmZnz38ueOwsbnY4cfGBRX30ueHHX4ItMVOTrcBuxbJZjZzY94zh80sZ6cZJ884U5y78XaaAVBLsrHZAexaDA4zmEkzth22MbidYHyYty0hd+PsBJCWA4nbcGixP8z+TfInWEv658O8/xLSDWenf8CrxYCZx0yCt+2wmcHtHONk3oaEBHnpHPy2SBzmKZPmbUs3BmopNuY5lmC4QTqn4ECCAW6/8Le3bwM6zNpww+30zdI8NQny8rPTN3/4UGEnh0sLFqeCVRoQqxwE5BtIUT0KRsEoGAUjAQAAN6lfeMAwSQoAAAAASUVORK5CYII=\",\"orcid\":\"\",\"institution\":\"Columbia University Irving Medical Center\",\"correspondingAuthor\":true,\"prefix\":\"\",\"firstName\":\"Elan\",\"middleName\":\"\",\"lastName\":\"Shukhmakher\",\"suffix\":\"\"},{\"id\":458296297,\"identity\":\"25319a80-dc88-4ef9-9697-7eaf57338cd6\",\"order_by\":1,\"name\":\"Yelena Akelina\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Columbia University Irving Medical Center\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Yelena\",\"middleName\":\"\",\"lastName\":\"Akelina\",\"suffix\":\"\"},{\"id\":458296298,\"identity\":\"03b84494-8ee3-4f08-a65b-b250cab2039d\",\"order_by\":2,\"name\":\"Robert J. 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Reports show instances of traumatic nerve injuries to be close to 350,000 cases per year, with the majority of those who suffered from such afflictions being young, having an average age of 32-39 [2]. \\u0026nbsp;Operative exploration of acutely transected nerves typically reveals some retraction of the nerve ends, known as the \\u0026ldquo;nerve gap\\u0026rdquo;. Mobilization of the nerve ends can often result in successful primary repair, however, if \\u0026ldquo;excessive\\u0026rdquo; tension exists at the repair site, a nerve graft may be more appropriate. Outcomes of nerve grafting are uniformly inferior to those of primary nerve repair [3], however the decision to perform nerve grafting as opposed to a primary repair is often a subjective one. What seems to be a \\u0026lsquo;tight\\u0026rsquo; nerve repair can often be remedied by adequate nerve mobilization, moderate adjacent joint flexion, and \\u0026lsquo;stress-relaxation\\u0026rsquo; by placing a few larger caliber sutures to take the tension off the repair and waiting a few minutes for the nerve to stretch out. With the increasing popularity of nerve allografting, it seems that fewer acutely transected nerves (within first two weeks of injury) are being repaired primarily owing to concerns of excessive tension at the repair site [4].\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eIt has been widely anecdotally observed that even when a nerve is freshly cut, there is a substantial nerve gap immediately created by the inherent elastic recoil of the nerve. The goal of the present study was to quantify the size of the acute nerve gap produced by rat sciatic nerve transection.\\u0026nbsp;\\u003c/p\\u003e\"},{\"header\":\"Methods\",\"content\":\"\\u003cp\\u003eTwenty-two live Sprague-Dawley male rats weighing ~300g were utilized for this study, allowing for 44 sciatic nerves to be dissected and transected by the same surgeon. All procedures received approval from the Columbia University Medical Center Institutional\\u003c/p\\u003e\\n\\u003cp\\u003eAnimal Care and Use Committee. All surgical manipulations were conducted under an operating-microscope (Zeiss OPMIMD; Carl Zeiss; Jena, Germany).\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eThe rats were initially anesthetized via a 75-95mg/Kg ketamine and 5-8mg/Kg xylazine intraperitoneal injection, and an intraperitoneal bolus was used throughout the procedure to maintain anesthesia. All animals were shaved, scrubbed with povidone iodine and alcohol, and positioned prone. Masking tape and pins to secure the arms and legs of the rat to the operating board were used, followed by placing 5 4x4 gauze underneath the leg of the rat, depending on which side was being operated on. Using a scalpel with a #15 blade, along with Adson tissue forceps and cotton tip applicators, blunt dissection at muscle planes between quadriceps femoris and biceps femoris exposed the right and left sciatic nerves of each rodent [Figure 1]. 1cm of the bilateral sciatic nerves were carefully exposed and released from the surrounding tissues without injury to vessels or nerve branches [Figure 2].\\u003c/p\\u003e\\n\\u003cp\\u003eThe diameter of the sciatic nerve at the site of the planned transection was measured using a Shinwa Sokutei 58698 crack scale scientific ruler [Figure 3]. With a fresh scalpel, the sciatic nerves were transected using a wooden spatula beneath the nerve to protect the underlying tissue [Figure 4]. Measurements of the gap between the nerve ends were measured using the ruler. Upon completion of the surgical procedure and collection of data, the animals were euthanized with a 100mg/Kg Euthasol Intraperitoneal injection. The primary outcome measure was the measured gap in the sciatic nerve following transection.\\u0026nbsp;\\u003c/p\\u003e\"},{\"header\":\"Results\",\"content\":\"\\u003cp\\u003eTwenty-two live Sprague-Dawley male rats were used as the eligible group in this study, resulting in 44 sciatic nerves being dissected, transected, and measured [Figure 5]. A mean nerve gap of 3.77mm was found with a range of 2mm to 6mm and a standard deviation of 1.06mm. The frequencies of the measured nerve gaps are shown in [Table 1]. The diameter of the sciatic nerves at the transection site was 1.82mm on average with a range of 1.4mm to 2.5mm and, a standard deviation of 0.27mm. The frequencies of the measured nerve diameters are shown in [Table 2].\\u003c/p\\u003e\\n\\u003cp\\u003eTable 1 Frequencies of Nerve Gaps\\u003c/p\\u003e\\n\\u003ctable border=\\\"1\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003eNerve Gap (Millimeters)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003eFrequency\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e6 (13.64%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e10 (22.73%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e3.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e4 (9.09%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e4\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e11 (25.00%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e4.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e1 (2.27%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e10 (22.73%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e5.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e1 (2.27%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e6\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e1 (2.27%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003eFrequencies of the nerve gap sizes observed, with 4mm representing the most frequent gap measured.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eTable 2 Frequencies of Nerve Diameters\\u003c/p\\u003e\\n\\u003ctable border=\\\"1\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003eNerve Diameter (Millimeters)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003eFrequency\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e1.4\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e1 (2.27%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e1.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e5 (11.36%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e1.6\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e6 (13.64%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e1.7\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e12 (27.27%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e1.8\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e2 (4.55%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e1.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e4 (9.09%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e2.0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e9 (20.45%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e2.2\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e2 (4.55%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e2.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd valign=\\\"top\\\" style=\\\"width: 311px;\\\"\\u003e\\n \\u003cp\\u003e3 (6.82%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003eFrequencies of the nerve diameter sizes observed, with1.7mm representing the most frequent diameter measured.\\u003c/p\\u003e\"},{\"header\":\"Discussion \",\"content\":\"\\u003cp\\u003eTreatment of chronic nerve lacerations involves trimming back the adjoining nerve ends to healthy fascicular patterns; this can result in substantial nerve gaps requiring some kind of bridging conduit, such as hollow tubes, allograft or autograft nerve interposition. In recent years, there has been increasing enthusiasm for repairing even acutely lacerated nerves with nerve allografts following the rationale that any tension on a nerve repair is detrimental to outcomes [4]. All acutely lacerated nerves will demonstrate some retraction of the ends, even seconds after the nerve is lacerated. When repairing recently lacerated nerves, the gap between the nerve ends caused by inherent elastic nerve recoil can typically be overcome by placing a few larger sutures and allowing the nerve to \\u0026ldquo;stress-relax\\u0026rdquo; to the point where a repair can be undertaken with fine sutures under less tension. Nevertheless, some practitioners suggest that even acutely sharply transected nerves be treated with interposition allograft repair, under the theory that any tension at the nerve repair site should be discouraged. The downside of interposition nerve grafting is that primary nerve repair under even moderate tension yields superior results to any interposition grafting procedure, even autografting [5] [6].\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eThe basic science shows that \\u003cem\\u003eacute\\u003c/em\\u003e significant stretching of a nerve is detrimental to nerve blood flow and thus healing [7], however substantial successful nerve elongation is possible over time, as occurs with limb or finger lengthening. Mackinnon has shown in a rat sciatic nerve model that acute nerve elongation to overcome a gap can be a problem, however if modest dissection and \\u0026lsquo;freeing up\\u0026rsquo; of the nerve is performed, then tension at the nerve repair site is markedly diminished [8]. In one of the few basic science primate studies on nerve repair, Hentz et al repaired the ulnar nerves of Cynomolgus monkeys either primarily under tension or by using an interposition autograft under no tension and found better results in the nerves repaired under tension without the autograft. They concluded that for defects of up to 3-4 cm in adult humans that modest tension across the nerve repair site was superior to using an auto or other graft to achieve a tension free repair [3].\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eTo the best of our knowledge, no data exists concerning the size of nerve gaps in acutely lacerated human nerves; such a study could be ethically performed examining gaps during intentional neurotomies associated with procedures such as denervations, nerve transfers or neuroma treatments. \\u0026nbsp; Therefore, this study has shown that at time zero an instantaneous gap is created by nerve transection owing to the inherent elastic recoil of the nerve itself. This gap, in the rat sciatic nerve model, is equivalent to twice the diameter of the nerve itself. If this were to be extrapolated to a human median nerve transection at the wrist, with a diameter of approximately 5 mm, this would be a 1 cm gap [9]. Clinically, we have observed gaps of over one cm in acutely lacerated median and ulnar nerves.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eThe point of this study is to show that even at time zero, there exists a significant nerve gap produced by nerve transection. Such a gap is usually seen following nerve transection and should be recognized as a normal finding, not a pathological nerve gap that necessarily requires a nerve graft.\\u003c/p\\u003e\\n\\u003cp\\u003eThis study is limited by examining only a single time point shortly following sciatic nerve transection. Although this allows for standardized measurement of the instantaneous gap, it does not take into account dynamic changes that may occur following injury, such as nerve retraction or early tissue remodeling. Although the rat sciatic nerve model is widely used for studies on peripheral nerves, anatomical and physiological differences in human and rat nervous systems can potentially hinder direct extrapolation. Nerve diameter, along with connective tissue and muscle composition surrounding the nerve, can influence gap development differently in human nerves and need to be considered while extrapolating the clinical relevance of results.\\u0026nbsp;\\u003c/p\\u003e\"},{\"header\":\"Conclusion \",\"content\":\"\\u003cp\\u003eNerve gaps measuring twice the diameter of the rat sciatic nerve are produced by acute nerve transection. This gap is likely related to the inherent elasticity of the nerve. Such acute nerve gaps will be easily overcome by primary nerve repair and typically will not require nerve auto or allografting.\\u003c/p\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eEthics approval and consent to participate\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eAll procedures received approval from the Columbia University Medical Center Institutional Animal Care and Use Committee.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConsent For Publication\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eNot applicable\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAvailability of data and materials\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eAll data generated or analyzed during this study are included in this published article [and its supplementary information files].\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eFunding\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eNot applicable\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAuthors contributions\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eE.S - Contributed to this study by conducting the experimental procedure, collecting the data, assisting in data analysis, and being primarily responsible for writing the manuscript. \\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eY.A- Contributed to the design of the experimental procedure, assisted in data analysis, and provided critical revisions and edits to the manuscript.\\u003c/p\\u003e\\n\\u003cp\\u003eR.S-\\u0026nbsp;Contributed to the design of the experimental procedure, assisted in data analysis, and provided critical revisions and edits to the manuscript.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAcknowledgments\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eNot applicable\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eList of abbreviations\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eNot applicable\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col class=\\\"decimal_type\\\"\\u003e\\n \\u003cli\\u003eZhang S, Huang M, Zhi J, Wu S, Wang Y, Pei F. Research hotspots and trends of peripheral nerve injuries based on web of science from 2017 to 2021: A bibliometric analysis. Frontiers; 2022. Available from:\\u0026nbsp;https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2022.872261/full\\u003c/li\\u003e\\n \\u003cli\\u003e1. Cruz AJM. Neurotmesis. U.S. National Library of Medicine; 2023. Available from:\\u0026nbsp;https://www.ncbi.nlm.nih.gov/books/NBK559108/\\u003c/li\\u003e\\n \\u003cli\\u003eHentz VR, Rosen JM, Xiao SJ, McGill KC, Abraham G. The nerve gap dilemma: A comparison of nerves repaired end to end under tension with nerve grafts in a primate model. U.S. National Library of Medicine; 1993. Available from:\\u0026nbsp;https://pubmed.ncbi.nlm.nih.gov/8515008/\\u003c/li\\u003e\\n \\u003cli\\u003eLans J, Eberlin K, Evans P, Mercer D, Greenberg J, Styron J. A systematic review and meta-analysis of Nerve Gap Repair: Comparative effectiveness of allografts, autografts, and Conduits. U.S. National Library of Medicine; 2022. Available from:\\u0026nbsp;https://pubmed.ncbi.nlm.nih.gov/36728885/\\u003c/li\\u003e\\n \\u003cli\\u003eMurovic JA. Upper-extremity peripheral nerve injuries: A Louisiana State University Health Sciences Center Literature Review with comparison of the operative outcomes of 1837 Louisiana State University Health Sciences Center Median, radial, and ulnar nerve lesions. U.S. National Library of Medicine; 2009. Available from:\\u0026nbsp;https://pubmed.ncbi.nlm.nih.gov/19927055/\\u003c/li\\u003e\\n \\u003cli\\u003eSallam A, Eldeeb M, Kamel N. Autologous fibrin glue versus microsuture in the surgical reconstruction of peripheral nerves: A randomized clinical trial. U.S. National Library of Medicine; 2021. Available from:\\u0026nbsp;https://pubmed.ncbi.nlm.nih.gov/34011463/\\u003c/li\\u003e\\n \\u003cli\\u003eYi C, Dahlin L. Impaired nerve regeneration and Schwann cell activation after repair with tension. U.S. National Library of Medicine; 2010. Available from:\\u0026nbsp;https://pubmed.ncbi.nlm.nih.gov/20729767/\\u003c/li\\u003e\\n \\u003cli\\u003eSunderland I, Brenner M, Singham J, Rickman S, Hunter D, Mackinnon S. Effect of tension on nerve regeneration in rat sciatic nerve transection model. U.S. National Library of Medicine; [cited 2004 Oct]. Available from: \\u0026nbsp;https://pubmed.ncbi.nlm.nih.gov/15385776/\\u003c/li\\u003e\\n \\u003cli\\u003eOrtiz R, Westenberg R, Langhammer C, Knaus W, Chen N, Eberlin K. Nerve diameter in the hand: A cadaveric study [Internet]. U.S. National Library of Medicine; 2019. Available from: https://pubmed.ncbi.nlm.nih.gov/31044121/\\u003c/li\\u003e\\n\\u003c/ol\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":true,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"bmc-plastic-and-reconstructive-surgery\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"\",\"sideBox\":\"Learn more about [BMC Plastic and Reconstructive Surgery](https://link.springer.com/journal/44452)\",\"snPcode\":\"44452\",\"submissionUrl\":\"https://submission.springernature.com/new-submission/44452/3\",\"title\":\"BMC Plastic and Reconstructive Surgery\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"stoa\",\"reportingPortfolio\":\"BMC Series\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":true},\"keywords\":\"nerve gap, transection, rat sciatic nerve\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-6590688/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-6590688/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003cp\\u003e\\u003cstrong\\u003eBackground \\u003c/strong\\u003eGaps following traumatic nerve transection can be overcome by nerve mobilization or by nerve grafting. Excessive tension across a nerve repair is thought to be detrimental to nerve healing leading many surgeons to perform nerve grafting in the setting of even modest tension across a nerve repair. Fresh nerve transections typically result in a nerve gap from the elastic recoil of the nerve itself. The size of the nerve gap created by a fresh transection of the rat sciatic nerve has previously not been quantified. The goal of this study was to measure the acute nerve gap produced by rat sciatic nerve transection.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eResults \\u003c/strong\\u003eThe average rat sciatic nerve gap size following transection was 3.77mm, with a range of 2mm-6mm. The average nerve diameter was 1.82mm, with a range of 1.4mm-2.5mm.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConclusion \\u003c/strong\\u003eImmediately following transection of the rat sciatic nerve, a gap equal to twice the diameter of the nerve is created. This gap is produced by the elastic recoil of the nerve.\\u003c/p\\u003e\",\"manuscriptTitle\":\"Time Zero Gap Created by Rat Sciatic Nerve Transection \",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2025-05-19 08:52:51\",\"doi\":\"10.21203/rs.3.rs-6590688/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"decision\",\"content\":\"Revision requested\",\"date\":\"2025-06-04T18:48:57+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2025-05-18T18:18:15+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"236981861720008219724865039195354122385\",\"date\":\"2025-05-16T19:18:31+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2025-05-14T23:40:22+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"182142701859248429392683303642779882952\",\"date\":\"2025-05-14T23:28:54+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"20800744890408494835601797695635214502\",\"date\":\"2025-05-14T21:16:05+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2025-05-14T20:13:12+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"33300178285463539348893900108280160300\",\"date\":\"2025-05-14T19:30:57+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewersInvited\",\"content\":\"\",\"date\":\"2025-05-14T18:44:03+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"checksComplete\",\"content\":\"\",\"date\":\"2025-05-14T17:37:43+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"submitted\",\"content\":\"BMC Plastic and Reconstructive Surgery\",\"date\":\"2025-05-14T17:36:37+00:00\",\"index\":\"\",\"fulltext\":\"\"}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"bmc-plastic-and-reconstructive-surgery\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"\",\"sideBox\":\"Learn more about [BMC Plastic and Reconstructive Surgery](https://link.springer.com/journal/44452)\",\"snPcode\":\"44452\",\"submissionUrl\":\"https://submission.springernature.com/new-submission/44452/3\",\"title\":\"BMC Plastic and Reconstructive Surgery\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"stoa\",\"reportingPortfolio\":\"BMC Series\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":true}}],\"origin\":\"\",\"ownerIdentity\":\"1dfe10a6-194f-4447-9ced-e85c97d37098\",\"owner\":[],\"postedDate\":\"May 19th, 2025\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"under-review\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2025-08-21T18:23:25+00:00\",\"versionOfRecord\":[],\"versionCreatedAt\":\"2025-05-19 08:52:51\",\"video\":\"\",\"vorDoi\":\"\",\"vorDoiUrl\":\"\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-6590688\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-6590688\",\"identity\":\"rs-6590688\",\"version\":[\"v1\"]},\"buildId\":\"XKTyCvWXoU3ODBz1xrDgd\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}