Rectal Sensory-Motor Alterations: A Clinical Perspective on Anorectal Disorders

Rectal Sensory-Motor Alterations: A Clinical Perspective on Anorectal Disorders | 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 Rectal Sensory-Motor Alterations: A Clinical Perspective on Anorectal Disorders Xinpeng Wang, Yanhui Gao, Li Xiao, Shuang Wang, Bohong Xu, Yu Zhi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4657186/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Altered rectal sensation and motility are prevalent in various anorectal disorders. However, the correlation between rectal sensation and motility has not been well-defined. The aims of this study are to determine the association between these two factors in anorectal disorders and to clarify the underlying mechanisms, thereby offering innovative insights for therapeutic approaches. Methods Retrospectively, we evaluated clinical data from 954 patients with anorectal disorders, who underwent high-resolution anorectal manometry for rectal motility and sensory testing. Regression analysis was performed to evaluate the associations between the rectal sensation and motility across different age and gender strata within different diseases. Results Significant variations in rectal sensations were observed across different diseases, with patients who had undergone rectal cancer surgery exhibiting the lowest sensory threshold volumes (P < 0.01). The constipated patients exhibited significant correlations between rectal sensory thresholds and motility (P < 0.001), with positive associations with maximum squeezing pressure and negative associations with rectoanal gradient and manometric defecation index. For rectal cancer and postoperative patients, only the maximum tolerable volume showed correlation with rectal motility (P < 0.05), including anal resting pressure, rectoanal gradient, and manometric defecation index. Regression analysis revealed that age and gender had a limited impact on the correlation between rectal sensation and motility. Conclusions Patients with anorectal diseases exhibit substantial variations in rectal sensation and motility, with a significant correlation observed between these factors. The correlation is notably influenced by age and gender in patients with constipation and rectal cancer, suggesting that similar relationships may be observed across various anorectal disorders. Registration number ChiCTR2400086148 Reg Date 2024-06-26 00:00:00 rectal sensation rectal motility anorectal disorders high-resolution anorectal manometry Figures Figure 1 Figure 2 Figure 3 Introduction Anorectal disorders, although not life-threatening, severely impact the quality of life. The complex process of defecation relies on intact anorectal sensation to detect rectal filling. Subsequently, the generation of adequate rectal propulsive force and the relaxation of the anal sphincter act synergistically to facilitate effective evacuation [ 1 ]. Recently, there has been a heightened focus on the role of sensory dysfunction in the occurrence and development of anorectal disorders among the majority of patients [ 2 ]. Furthermore, rectal hyposensitivity has been identified as a factor that can adversely impact the efficacy of certain treatments. It has been suggested as a critical target for intervention to restore normal rectal sensation in patients with anorectal disorders[ 3 ]. Conversely, rectal hypersensitivity has been observed in patients with urge fecal incontinence (FI) and irritable bowel syndrome (IBS), underscoring the diverse sensory dysregulations associated with these conditions [ 4 ]. Furthermore, the degree of clinical manifestation in patients with anorectal disorders is significantly associated with alterations in rectal sensation and motility [ 5 – 7 ]. Sun WM et al. have found that in patients with FI, rectal sensation is closely related to the contraction of the external anal sphincter. Upon relaxation of the internal anal sphincter, the delayed or absent contraction of the external anal sphincter may lead to FI [ 8 ]. After patients with FI were stratified into a rectal hypersensitivity group and a normal group, revealing that those in the rectal hypersensitivity group showed enhanced rectal contractility [ 9 ]. Therefore, we hypothesize that there exists a potentially inseparable relationship between rectal sensation and rectal motility, which we aim to investigate further in this study. Method Participants We retrospectively analyzed data from 954 patients with anorectal disorders who had completed high-resolution anorectal manometry and undergone rectal sensory testing at the pelvic floor center of Xinhua Hospital Affiliated to Dalian University from January 2018 to April 2023. Participants with long-standing metal or electronic implants, pregnant individuals, those with a history of other malignancies, patients afflicted with severe mental or psychological disorders, and subjects under the age of 18 were excluded from the study. According to the age classification criteria published by the World Health Organization (WHO) in 2020, all patients were categorized into three groups: the youth group (≤ 44 years old), the middle-aged group (45–59 years old), and the elderly group (≥ 60 years old). The median volume of each rectal sensory threshold was used as the limit. Patients with values above those limits were classified as insensitive patients, while those with values below were classified as sensitive. The research plan was approved by the ethics review committee of Xinhua Hospital Affiliated to Dalian University (2023-93-01). High-resolution anorectal manometry The 24 channel water-perfused catheter (Ningbo Maida Medical Device, Ningbo, China) was utilized for all patients. Enema was administered 30 minutes prior to the examination to ensure bowel preparation. Patients were positioned in the left lateral position with flexed hips and knees during the examination. The catheter was then lubricated and inserted into the rectum. After the patients were comfortably positioned and the pressures had stabilized, the anal resting pressure was measured. Then, patients were instructed to squeeze their anus for more than 30 seconds to obtain the maximum squeezing pressure. Subsequently, patients were asked to simulate evacuation for more than 15 seconds, during which the rectal pressure and anal residual pressure were recorded. Rectoanal gradient was the difference between rectal and anal residual pressures. In addition to rectoanal gradient, the manometric defecation index, a quantification parameter of pressure changes, was calculated as the ratio of rectal pressure to anal pressure. Rectal sensation was assessed by gradually inflating the rectal balloon with a hand-held syringe. Patients were instructed to orally report their first sensation, desire to defecate, maximum toleration, or pain. The threshold volumes for the first constant sensation volume (FCSV), defecatory desire volume (DDV), and maximum tolerable volume (MTV) were then recorded. Statistical Analysis Age, gender, the results of anorectal manometry and rectal sensation for all patients were included in the statistical analysis, and the rectoanal gradient and manometric defecation index were calculated. All data were analyzed by SPSS version 23.0, and the graphics were made by GraphPad Prism 9. Chi-square test was used to compare the categorical variables. Shapiro-Wilk test was used to analyze the normality of rectal sensation and motility test results of different diseases. It was found that rectal motility in patients with rectal cancer after surgery and anal resting pressure in patients with FI were normal distributed within different sensory groups. One-way analysis of variance and t-test were employed to analyze normal distributions variables, and the rank sum test was used for non-normal distributions. Spearman correlation was utilized to analyze the correlation between different rectal sensation and rectal motility. Simple linear regression analysis was conducted to evaluate the impact of sensation on motility. Bilateral P values less than 0.05 were considered statistically significant. Result Demographics The mean age of the patients was 56.5 ± 13.7 years for men and 62.1 ± 13.0 years for women. The demographic information of the included patients is summarized in Table 1 . Within the same age group, young and middle-aged females were more likely to have anorectal disorders than males (P = 0.001, and P < 0.001, respectively), while elderly males were more likely to suffer from anorectal disorders than females (P < 0.001). Constipation was the most common anorectal disorder in females (P < 0.001), whereas rectal cancer and postoperative patients were common in males (P < 0.001, and P = 0.011, respectively). Table 1 Characteristics of the Study Population (n = 954). Characteristics Men (n = 346) Women (n = 608) p-value Age(years) ≤ 44 40 (11.5%) 120 (19.7%) 0.001 45–59 67 (19.4%) 206 (33.9%) < 0.001 ≥ 60 239 (69.1%) 282 (46.4%) < 0.001 Comorbidities Constipation 240 (69.4%) 534 (87.8%) < 0.001 Fecal incontinence 20 (5.8%) 24 (3.9%) 0.128 Rectal cancer 69 (19.9%) 38 (6.3%) < 0.001 After rectal cancer surgery 17 (4.9%) 12 (2%) 0.011 Differences of rectal sensation in different diseases. The sensory threshold for FCSV was significantly lower in postoperative rectal cancer patients than in those with constipation, FI and rectal cancer (P < 0.001, P < 0.01, and P < 0.01, respectively). Similarly, the sensory threshold for DDV was significantly lower in postoperative rectal cancer patients than in those with constipation, FI and rectal cancer (P < 0.001, P < 0.001 and P < 0.001, respectively). The sensory threshold for DDV in rectal cancer was significantly lower than in constipation (P < 0.05). Furthermore, the sensory threshold for MTV in postoperative rectal cancer patients was significantly lower than in those with constipation, FI and rectal cancer (P < 0.001, P < 0.001 and P < 0.001, respectively). And the sensory threshold for MTV in rectal cancer patients was significantly lower than that in patients with constipation (P < 0.001). (Fig. 1 ) Variations of rectal motility in different rectal sensations. Supplementary Table 2 summarizes the rectal motility differences of patients with anorectal disorders under different sensory thresholds. In constipated patients with FCSV, the anal resting pressure was significantly higher in the insensitive group compared to the sensitive group (P = 0.020); The maximum squeezing pressure was significantly higher in the insensitive group compared to both the sensitive and normal groups (P < 0.001); The rectoanal gradient in the insensitive and normal groups was lower than that in the sensitive group (P < 0.001); The manometric defecation index in the sensitive group was significantly higher than those in the normal and insensitive groups (P < 0.001). In constipated patients with DDV, the maximum squeezing pressure was significantly higher in the insensitive group compared to the sensitive group (P = 0.001); The rectoanal gradient was lower in the insensitive group compared to both the sensitive and normal groups (P < 0.001); The manometric defecation index in the insensitive group was lower than that in both the sensitive and normal groups (P < 0.001). In constipated patients with MTV, the maximum squeezing pressure of the normal group was higher than that of the sensitive group (P = 0.006). For rectal cancer patients, only under the MTV, the rectoanal gradient of the insensitive group was lower than that of the sensitive group (P = 0.022), and the manometric defecation index of the insensitive group was lower than that of the sensitive group (P = 0.028). For postoperative patients, only under the MTV, the rectoanal gradient of the insensitive group was higher than that of the sensitive group (P = 0.012), and manometric defecation index of the insensitive group was lower than those of the sensitive group (P = 0.018). Correlation between rectal sensation and motility. In constipated patients, we found that maximum squeezing pressure was positively correlated with each sensory threshold volume (r = 0.1253, P < 0.001; r = 0.1361, P = 0.001 and r = 0.1217, P < 0.001, respectively). The rectoanal gradient (r=-0.1917, P < 0.001; r=-0.1717, P < 0.001 and r=-0.1177, P = 0.001, respectively) and manometric defecation index (r=-0.1765, P < 0.001; r=-0.1618, P < 0.001 and r=-0.1005, P < 0.005, respectively) were inversely correlated with each sensory threshold volume. In rectal cancer patients, the anal resting pressure was positively correlated with the MTV (r = 0.02072, P = 0.032). The rectoanal gradient and manometric defecation index were inversely correlated with the MTV (r=-0.2226, P = 0.021, and r=-0.2158, P = 0.026, respectively). In rectal cancer patients after surgery, the rectoanal gradient and manometric defecation index were also inversely correlated with MTV (r=-0.3924, P = 0.035, and r=-0.4214, P = 0.023, respectively). (Fig. 2 ) Considering the distinct age and gender distribution among patients with various anorectal diseases, we aim to investigate whether these two factors exert influence on the correlation between rectal sensation and motility. Among patients with constipation, the rectoanal gradient and manometric defecation index showed inverse correlations with the FCSV (R²=0.023, P = 0.039, and R²=0.01936, P = 0.033, respectively) in middle-aged females, with only the rectoanal gradient showing an inverse correlation with the FCSV (R²=0.0301, P = 0.018) in elderly females. Additionally, the rectoanal gradient was inversely related to the DDV (R²=0.02266, P = 0.040) in middle-aged females, while both the rectoanal gradient and manometric defecation index demonstrated inverse correlations with the DDV (R²=0.01829, P = 0.039, and R²=0.02376, P = 0.036, respectively) in elderly females. Moreover, the rectoanal gradient was inversely correlated with the MTV (R²=0.04384, P = 0.025) in young females, and the maximum squeezing pressure showed a positive correlation with the MTV (R²=0.02921, P = 0.027) in elderly females. Notably, the constipated patients in the middle-aged and elderly groups exhibited a stronger correlation between rectal sensation and motility within the FCSV group compared to the DDV group (R²=0.023 VS R²=0.02266, and R²=0.01936 VS R²=0.01829, respectively). All male patients with rectal cancer were in the middle-aged group, and their maximum squeezing pressure was positively correlated with MTV (R²=0.06153, P = 0.040). Conversely, in elderly female patients with rectal cancer, the manometric defecation index was inversely correlated with the MTV (R²=0.08826, P = 0.013). (Fig. 3 ) Discussion Intact rectal sensation, which is maintained by the normal functioning of rectal afferent nerves and the rectal wall, leads to the sensation of defecatory urge [ 10 ]. Abnormalities in rectal sensation have been postulated as a potential pathophysiological mechanism in anorectal disorders. Thiruppathy et al. demonstrated that patients with urge FI and constipation exhibit relatively distinct rectal sensation profiles [ 11 ]. Based on the above research, we are also interested in investigating rectal sensation in patients with rectal cancer, as well as in postoperative patients exhibiting symptoms of anorectal disorders. Due to the reduced maximum tolerable volume and rectal compliance in postoperative patients, a small amount of content can trigger the defecatory urge, necessitating frequent defecation [ 12 ]. This structural damage significantly affects the quality of life, resulting in significantly elevated rectal sensation thresholds compared to other diseases. Ihnat et al. found that patients who have undergone rectal cancer surgery often experience alterations in rectal sensitivity, typically accompanied by mild to moderate anorectal disorders, characterized by decreased anal resting and maximum squeezing pressures, as well as reduced rectal volume and compliance [ 13 ]. Therefore, we anticipate that exploring the relationship between rectal sensation and motility will shed light on the underlying pathophysiological mechanisms of various anorectal diseases, thereby enhancing diagnostic precision and therapeutic strategies. One or even two abnormal rectal sensory threshold volumes were found in most anorectal disorders through rectal sensory testing, and it is speculated that each sensory threshold volume may represent different pathophysiological pathways [ 5 ]. In this study, we attempted to classify patients into sensitive and insensitive groups based on the same sensory threshold volumes to analyze rectal motility. According to the London Classification, the determination of rectal sensory abnormalities requires comparison with established normal values [ 14 ], however, determining the precise range for a normal threshold remains a challenge. In the healthy population, females exhibit significantly lower rectal sensory thresholds than males [ 15 ], and these thresholds tend to decrease with the increase of age [ 16 ]. Additionally, BMI has been identified as a factor influencing rectal sensory thresholds [ 17 ]. The sensation of rectal fullness induces the relaxation of the internal anal sphincter and the contraction of the external anal sphincter, which are crucial stages in the defecation process [ 18 ]. Fox et al. found that the first sensation occurs when the function of the internal anal sphincter is threatened, and the urge to defecate emerges as the function of the external anal sphincter is threatened [ 19 ]. Nevertheless, the precise correlation between rectal motility and sensation in anorectal disorders is not yet clear. Patients with anorectal disorders often experience weak propulsive forces, heightened resistance during defecation, or both. Moreover, a long term negative anorectal gradient and anorectal dyssynergia can aggravate symptoms [ 7 ]. Training in the coordinated contraction of pelvic floor muscles and the relaxation of the anal sphincters to facilitate rectal evacuation has been demonstrated to enhance rectal sensation [ 20 ]. Our study found that patients in the insensitivity group exhibited elevated anal resting pressure and maximum squeezing pressure, as well as dyssynergic defecation and inadequate propulsive efforts, which is consistent with characteristics observed in constipated patients with rectal hyposensitivity in previous research [ 20 , 21 ]. In addition, the constipated patients with rectal hyposensitivity require a greater volume to trigger the anorectal contraction reflex [ 22 ]. Some patients who lack the urge to defecate often actively increase abdominal pressure in an attempt to defecate, which can lead to uncoordinated movement of the pelvic floor muscles during this process. Proper guidance and training can help these patients establish good defecation habits, thereby enhancing their rectal sensation to some degree [ 23 ]. Rectal motility varies according to different rectal sensations. Following the insertion of a balloon filled with an appropriate volume into the rectum of constipated patients with normal rectal sensation, an increase in the rectoanal gradient, correction of dyssynergic defecation, and improvements in the patients’ symptoms were observed. However, stimulation patients with decreased rectal sensitivity using the same method did not result in any improvement [ 17 ]. Moreover, we observed that all three rectal sensory threshold volumes in constipated patients were significantly correlated with rectal motility. All of these correlations indicated that as sensory threshold volumes increased, the maximum squeezing pressure of patients increased, while the rectoanal gradient and manometric defecation index both decreased. This correlation was weaker in rectal cancer and postoperative patients, and it was only found in the MTV. These findings suggest that different diseases possess unique characteristics that may facilitate diagnosis and therapeutic advancements in the future. In Jiang et al. research, DDV was elevated in all hyposensitivity functional anorectal disorder patients, and it was speculated as a useful indicator for the diagnosis of rectal sensation impairment [ 24 ]. However, our findings revealed that each sensory threshold volume in constipated patients exhibited significant correlations with motility, with FCSV showing the most pronounced correlation. Therefore, we speculate that FCSV may be the most reliable indicator for assessing rectal sensory impairment and predicting motor function performance. Similarly, in our study, only MTV was significantly correlated with rectal motility in rectal cancer patients and postoperative patients, suggesting that MTV may be the best predictive indicator for both groups. Age and gender play significant roles in rectal sensation and motility. Rectal sensory threshold volumes tend to increase with advancing age, particularly in males [ 25 ], whereas motility tends to decline with age, more prominently in females [ 26 ]. Noelting et al. reported that healthy older women exhibit a greater rectoanal gradient than younger women [ 27 ]. Conversely, our research found that, under the same FCSV and DDV, middle-aged female patients with constipation have a higher rectoanal gradient than elderly female patients. Consequently, the influence of age and gender on this correlation is still uncertain. Furthermore, we observed that in middle-aged and elderly female patients with constipation, FCSV had a more pronounced effect on the rectoanal gradient than DDV. Overall, although the influence of age and gender on these correlations is limited, it remains significant and should not be overlooked, in order to better understand and treat anorectal diseases in clinical practice. This study is constrained by its retrospective design and the varying number of subjects across the different disease categories. In addition, our study focused solely on the correlation between rectal sensation and rectal motility. However, it is important to note that sensory afferent nerve terminals involved in defecation are present not only in the rectum but also in the anal canal, and their functions are not entirely identical [ 28 ]. Both patients with rectal hyposensitivity and normal sensation may present with abnormal anal canal sensation [ 29 ]. The interplay between rectal sensation, anal canal sensation, and their respective correlations with motility requires further investigation. In conclusion, our data indicate that various anorectal disorders present unique profiles of rectal sensation and motility, among which postoperative rectal cancer patients demonstrating the highest rectal sensitivity. Patients with constipation exhibit differences in rectal motility among all three rectal sensory conditions, and the rectal motility of rectal cancer and postoperative patients only show differences in MTV. In patients with constipation, both the rectoanal pressure gradient and the manometric defecation index decrease as the three rectal sensory threshold volumes increase. Rectal cancer and postoperative patients exhibited clinical manifestations similar to those of constipated patients, but these similarities were only observed under the MTV. This study not only revealed the differences in rectal sensation among anorectal disorders but also provided insights for improving rectal motility and diagnosing diseases, thereby laying the foundation for the development of individualized treatment for patients. Declarations Financial support: This work was supported by Liaoning Revitalization Talents Program (No. XLYC2007028). Competing Interests: None Ethics approval: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The study was approved by the ethics review committee of Xinhua Hospital Affiliated to Dalian University (No.2023-93-01). Consent to participate: Informed consent was obtained from all individual participants included in the study. Data availability The datasets generated or analyzed during the study are available from the corresponding author on reasonable request. Author contributions Xinpeng Wang conducted data analysis and wrote the draft of the manuscript. Yanhui Gao, Li Xiao, Shuang Wang and Bohong Xu contributed to data collection and interpretation. Yu Zhi designed and supervised the experiments, and performed critical revisions of the manuscript. 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Front Med (Lausanne) 10:1119617 Abe T, Kunimoto M, Hachiro Y et al (2023) Effects of Age and Sex on the Anorectal Sensory Threshold to Electrical Stimulation: A Single-center Observational Study. J Anus Rectum Colon 7:74–81 Gundling F, Seidl H, Scalercio N, Schmidt T, Schepp W, Pehl C (2010) Influence of gender and age on anorectal function: normal values from anorectal manometry in a large caucasian population. Digestion 81:207–213 Noelting J, Ratuapli SK, Bharucha AE, Harvey DM, Ravi K, Zinsmeister AR (2012) Normal values for high-resolution anorectal manometry in healthy women: effects of age and significance of rectoanal gradient. Am J Gastroenterol 107:1530–1536 Knowles CH (2018) Human studies of anorectal sensory function. Ir J Med Sci 187:1143–1147 Vasudevan SP, Scott SM, Gladman MA, Lunniss PJ (2007) Rectal hyposensitivity: evaluation of anal sensation in female patients with refractory constipation with and without faecal incontinence. Neurogastroenterol Motil 19:660–667 Additional Declarations No competing interests reported. Supplementary Files SupplementaryNostatisticallysignificantresults.pdf SupplementaryTable2.pdf Cite Share Download PDF Status: Posted Version 1 posted 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-4657186","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":323567949,"identity":"e376e211-71a0-4b71-9d1e-a2e27ec40ef0","order_by":0,"name":"Xinpeng Wang","email":"","orcid":"","institution":"Xinhua Hospital Affiliated to Dalian University","correspondingAuthor":false,"prefix":"","firstName":"Xinpeng","middleName":"","lastName":"Wang","suffix":""},{"id":323567950,"identity":"780a8b62-68c2-4e1a-b4b7-80f022df70c8","order_by":1,"name":"Yanhui Gao","email":"","orcid":"","institution":"Xinhua Hospital Affiliated to Dalian University","correspondingAuthor":false,"prefix":"","firstName":"Yanhui","middleName":"","lastName":"Gao","suffix":""},{"id":323567951,"identity":"db058225-b50b-4a1d-b384-4934b826f64a","order_by":2,"name":"Li Xiao","email":"","orcid":"","institution":"Xinhua Hospital Affiliated to Dalian University","correspondingAuthor":false,"prefix":"","firstName":"Li","middleName":"","lastName":"Xiao","suffix":""},{"id":323567952,"identity":"ec7555a5-dd83-4c40-bded-910c0258f726","order_by":3,"name":"Shuang Wang","email":"","orcid":"","institution":"Dalian University, Dalian Economic and Technological Development Zone","correspondingAuthor":false,"prefix":"","firstName":"Shuang","middleName":"","lastName":"Wang","suffix":""},{"id":323567953,"identity":"83abc12a-426f-45d5-9854-71c758d59b86","order_by":4,"name":"Bohong Xu","email":"","orcid":"","institution":"Xinhua Hospital Affiliated to Dalian University","correspondingAuthor":false,"prefix":"","firstName":"Bohong","middleName":"","lastName":"Xu","suffix":""},{"id":323567954,"identity":"1d41017e-8e8f-4fd1-8f08-36ebd1eb88d7","order_by":5,"name":"Yu Zhi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA9UlEQVRIiWNgGAWjYJACZgaGAzxA6sCBhAobHn7+BoI6GJshWtgSH3w4kyYjOeMAcVqANI+x4cyWwzYGDQn41Zuz9z5/XPDnjozBjQQzad6G8zwGDAcYP3zMwa3Fsue4YfMMnmc8QC1p0rw7bvOYMzcwS87chluLwY00xmYeicMgLcekec/c5rFsOMDGzEtQiwFIS2KbNG/bOR6DAwnEaEkAaUlmNpzZdoAILWeOMc7mOXCYR/LMM0ZgICfzSM442IzfL8fbGD7z/Dlsz3c8/wMwKu3s+fmbD374iEcLHCgcgDMZG4hQDwTyRKobBaNgFIyCEQgAG4JZnhuw8HgAAAAASUVORK5CYII=","orcid":"","institution":"Xinhua Hospital Affiliated to Dalian University","correspondingAuthor":true,"prefix":"","firstName":"Yu","middleName":"","lastName":"Zhi","suffix":""}],"badges":[],"createdAt":"2024-06-29 02:38:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4657186/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4657186/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":60912738,"identity":"e48ed46a-1cd3-466f-95ca-bbe4a6ecf535","added_by":"auto","created_at":"2024-07-23 13:05:13","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":259090,"visible":true,"origin":"","legend":"\u003cp\u003eVariations of rectal motility in different rectal sensations\u003c/p\u003e\n\u003cp\u003e(A) Comparison of FCSV in different diseases. (B) Comparison of DDV in different diseases. (C) Comparison of MTV in different diseases. *p\u0026lt;0.05 **p\u0026lt;0.01 ***p\u0026lt;0.001\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4657186/v1/e1689f1e931827869edcbd48.jpeg"},{"id":60912741,"identity":"998a1f0d-ae7f-44bc-b2e8-db9e9cc42b7a","added_by":"auto","created_at":"2024-07-23 13:05:13","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":349805,"visible":true,"origin":"","legend":"\u003cp\u003eCorrelation between rectal sensation and motility.\u003c/p\u003e\n\u003cp\u003e(A) Correlation between FCSV and rectal motility in patients with constipation. (B) Correlation between DDV and rectal motility in patients with constipation. (C) Correlation between MTV and rectal motility in patients with constipation. (D) Correlation between MTV and rectal motility in patients with rectal cancer. (E) Correlation between MTV and rectal motility in postoperative patients with rectal cancer.\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4657186/v1/4381ad964adce4e1c30cb7c9.jpeg"},{"id":60912739,"identity":"46cd1369-592b-4dd3-b2bc-154fa3f33443","added_by":"auto","created_at":"2024-07-23 13:05:13","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":392662,"visible":true,"origin":"","legend":"\u003cp\u003eRegression analysis of the influence of age and gender on correlation.\u003c/p\u003e\n\u003cp\u003e(A) Patients with constipation in FCSV group regression analysis of the influence of age and gender on correlation between rectal sensation and motility. (B) Patients with constipation in DDV group regression analysis of the influence of age and gender on rectal motility. (C) Patients with constipation in MTV group regression analysis of the influence of age and gender on rectal motility. (D) Patients with rectal cancer in MTV group regression analysis of the influence of age and gender on rectal motility.\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4657186/v1/ea419c8fbdeecfc7de3afbe0.jpeg"},{"id":73155050,"identity":"857e3fde-fa79-4060-b67f-cd69f26f9218","added_by":"auto","created_at":"2025-01-07 08:54:33","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1403289,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4657186/v1/1bbd278e-fe02-4539-8826-86acba4f608a.pdf"},{"id":60912737,"identity":"84a2714a-2f60-411c-8ef8-9ca3ffebf348","added_by":"auto","created_at":"2024-07-23 13:05:13","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":1841480,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryNostatisticallysignificantresults.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4657186/v1/0df3d4db2dba94f517b89e61.pdf"},{"id":60913556,"identity":"92d46c6f-5e84-485a-af6e-855f895608bf","added_by":"auto","created_at":"2024-07-23 13:13:13","extension":"pdf","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":128060,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryTable2.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4657186/v1/e4e46b7877561824edb7e217.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Rectal Sensory-Motor Alterations: A Clinical Perspective on Anorectal Disorders","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAnorectal disorders, although not life-threatening, severely impact the quality of life. The complex process of defecation relies on intact anorectal sensation to detect rectal filling. Subsequently, the generation of adequate rectal propulsive force and the relaxation of the anal sphincter act synergistically to facilitate effective evacuation [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Recently, there has been a heightened focus on the role of sensory dysfunction in the occurrence and development of anorectal disorders among the majority of patients [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Furthermore, rectal hyposensitivity has been identified as a factor that can adversely impact the efficacy of certain treatments. It has been suggested as a critical target for intervention to restore normal rectal sensation in patients with anorectal disorders[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Conversely, rectal hypersensitivity has been observed in patients with urge fecal incontinence (FI) and irritable bowel syndrome (IBS), underscoring the diverse sensory dysregulations associated with these conditions [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eFurthermore, the degree of clinical manifestation in patients with anorectal disorders is significantly associated with alterations in rectal sensation and motility [\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Sun WM et al. have found that in patients with FI, rectal sensation is closely related to the contraction of the external anal sphincter. Upon relaxation of the internal anal sphincter, the delayed or absent contraction of the external anal sphincter may lead to FI [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. After patients with FI were stratified into a rectal hypersensitivity group and a normal group, revealing that those in the rectal hypersensitivity group showed enhanced rectal contractility [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Therefore, we hypothesize that there exists a potentially inseparable relationship between rectal sensation and rectal motility, which we aim to investigate further in this study.\u003c/p\u003e"},{"header":"Method","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eParticipants\u003c/h2\u003e \u003cp\u003eWe retrospectively analyzed data from 954 patients with anorectal disorders who had completed high-resolution anorectal manometry and undergone rectal sensory testing at the pelvic floor center of Xinhua Hospital Affiliated to Dalian University from January 2018 to April 2023. Participants with long-standing metal or electronic implants, pregnant individuals, those with a history of other malignancies, patients afflicted with severe mental or psychological disorders, and subjects under the age of 18 were excluded from the study. According to the age classification criteria published by the World Health Organization (WHO) in 2020, all patients were categorized into three groups: the youth group (\u0026le;\u0026thinsp;44 years old), the middle-aged group (45\u0026ndash;59 years old), and the elderly group (\u0026ge;\u0026thinsp;60 years old). The median volume of each rectal sensory threshold was used as the limit. Patients with values above those limits were classified as insensitive patients, while those with values below were classified as sensitive. The research plan was approved by the ethics review committee of Xinhua Hospital Affiliated to Dalian University (2023-93-01).\u003c/p\u003e \u003cdiv id=\"Sec4\" class=\"Section3\"\u003e \u003ch2\u003eHigh-resolution anorectal manometry\u003c/h2\u003e \u003cp\u003eThe 24 channel water-perfused catheter (Ningbo Maida Medical Device, Ningbo, China) was utilized for all patients. Enema was administered 30 minutes prior to the examination to ensure bowel preparation. Patients were positioned in the left lateral position with flexed hips and knees during the examination. The catheter was then lubricated and inserted into the rectum. After the patients were comfortably positioned and the pressures had stabilized, the anal resting pressure was measured. Then, patients were instructed to squeeze their anus for more than 30 seconds to obtain the maximum squeezing pressure. Subsequently, patients were asked to simulate evacuation for more than 15 seconds, during which the rectal pressure and anal residual pressure were recorded. Rectoanal gradient was the difference between rectal and anal residual pressures. In addition to rectoanal gradient, the manometric defecation index, a quantification parameter of pressure changes, was calculated as the ratio of rectal pressure to anal pressure. Rectal sensation was assessed by gradually inflating the rectal balloon with a hand-held syringe. Patients were instructed to orally report their first sensation, desire to defecate, maximum toleration, or pain. The threshold volumes for the first constant sensation volume (FCSV), defecatory desire volume (DDV), and maximum tolerable volume (MTV) were then recorded.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eAge, gender, the results of anorectal manometry and rectal sensation for all patients were included in the statistical analysis, and the rectoanal gradient and manometric defecation index were calculated. All data were analyzed by SPSS version 23.0, and the graphics were made by GraphPad Prism 9. Chi-square test was used to compare the categorical variables. Shapiro-Wilk test was used to analyze the normality of rectal sensation and motility test results of different diseases. It was found that rectal motility in patients with rectal cancer after surgery and anal resting pressure in patients with FI were normal distributed within different sensory groups. One-way analysis of variance and t-test were employed to analyze normal distributions variables, and the rank sum test was used for non-normal distributions. Spearman correlation was utilized to analyze the correlation between different rectal sensation and rectal motility. Simple linear regression analysis was conducted to evaluate the impact of sensation on motility. Bilateral P values less than 0.05 were considered statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Result","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eDemographics\u003c/h2\u003e \u003cp\u003eThe mean age of the patients was 56.5\u0026thinsp;\u0026plusmn;\u0026thinsp;13.7 years for men and 62.1\u0026thinsp;\u0026plusmn;\u0026thinsp;13.0 years for women. The demographic information of the included patients is summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Within the same age group, young and middle-aged females were more likely to have anorectal disorders than males (P\u0026thinsp;=\u0026thinsp;0.001, and P\u0026thinsp;\u0026lt;\u0026thinsp;0.001, respectively), while elderly males were more likely to suffer from anorectal disorders than females (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Constipation was the most common anorectal disorder in females (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), whereas rectal cancer and postoperative patients were common in males (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001, and P\u0026thinsp;=\u0026thinsp;0.011, respectively).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCharacteristics of the Study Population (n\u0026thinsp;=\u0026thinsp;954).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eCharacteristics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMen\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;346)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eWomen\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;608)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eAge(years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026le;\u0026thinsp;44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e40 (11.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e120 (19.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e45\u0026ndash;59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e67 (19.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e206 (33.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e239 (69.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e282 (46.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eComorbidities\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eConstipation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e240 (69.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e534 (87.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFecal incontinence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20 (5.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e24 (3.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.128\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRectal cancer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e69 (19.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e38 (6.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAfter rectal cancer surgery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17 (4.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e12 (2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.011\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eDifferences of rectal sensation in different diseases.\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThe sensory threshold for FCSV was significantly lower in postoperative rectal cancer patients than in those with constipation, FI and rectal cancer (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001, P\u0026thinsp;\u0026lt;\u0026thinsp;0.01, and P\u0026thinsp;\u0026lt;\u0026thinsp;0.01, respectively). Similarly, the sensory threshold for DDV was significantly lower in postoperative rectal cancer patients than in those with constipation, FI and rectal cancer (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001 and P\u0026thinsp;\u0026lt;\u0026thinsp;0.001, respectively). The sensory threshold for DDV in rectal cancer was significantly lower than in constipation (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Furthermore, the sensory threshold for MTV in postoperative rectal cancer patients was significantly lower than in those with constipation, FI and rectal cancer (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001 and P\u0026thinsp;\u0026lt;\u0026thinsp;0.001, respectively). And the sensory threshold for MTV in rectal cancer patients was significantly lower than that in patients with constipation (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eVariations of rectal motility in different rectal sensations.\u003c/b\u003e \u003c/p\u003e \u003cp\u003eSupplementary Table\u0026nbsp;2 summarizes the rectal motility differences of patients with anorectal disorders under different sensory thresholds. In constipated patients with FCSV, the anal resting pressure was significantly higher in the insensitive group compared to the sensitive group (P\u0026thinsp;=\u0026thinsp;0.020); The maximum squeezing pressure was significantly higher in the insensitive group compared to both the sensitive and normal groups (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001); The rectoanal gradient in the insensitive and normal groups was lower than that in the sensitive group (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001); The manometric defecation index in the sensitive group was significantly higher than those in the normal and insensitive groups (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). In constipated patients with DDV, the maximum squeezing pressure was significantly higher in the insensitive group compared to the sensitive group (P\u0026thinsp;=\u0026thinsp;0.001); The rectoanal gradient was lower in the insensitive group compared to both the sensitive and normal groups (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001); The manometric defecation index in the insensitive group was lower than that in both the sensitive and normal groups (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). In constipated patients with MTV, the maximum squeezing pressure of the normal group was higher than that of the sensitive group (P\u0026thinsp;=\u0026thinsp;0.006).\u003c/p\u003e \u003cp\u003eFor rectal cancer patients, only under the MTV, the rectoanal gradient of the insensitive group was lower than that of the sensitive group (P\u0026thinsp;=\u0026thinsp;0.022), and the manometric defecation index of the insensitive group was lower than that of the sensitive group (P\u0026thinsp;=\u0026thinsp;0.028). For postoperative patients, only under the MTV, the rectoanal gradient of the insensitive group was higher than that of the sensitive group (P\u0026thinsp;=\u0026thinsp;0.012), and manometric defecation index of the insensitive group was lower than those of the sensitive group (P\u0026thinsp;=\u0026thinsp;0.018).\u003c/p\u003e \u003cp\u003e \u003cb\u003eCorrelation between rectal sensation and motility.\u003c/b\u003e \u003c/p\u003e \u003cp\u003eIn constipated patients, we found that maximum squeezing pressure was positively correlated with each sensory threshold volume (r\u0026thinsp;=\u0026thinsp;0.1253, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001; r\u0026thinsp;=\u0026thinsp;0.1361, P\u0026thinsp;=\u0026thinsp;0.001 and r\u0026thinsp;=\u0026thinsp;0.1217, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001, respectively). The rectoanal gradient (r=-0.1917, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001; r=-0.1717, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001 and r=-0.1177, P\u0026thinsp;=\u0026thinsp;0.001, respectively) and manometric defecation index (r=-0.1765, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001; r=-0.1618, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001 and r=-0.1005, P\u0026thinsp;\u0026lt;\u0026thinsp;0.005, respectively) were inversely correlated with each sensory threshold volume. In rectal cancer patients, the anal resting pressure was positively correlated with the MTV (r\u0026thinsp;=\u0026thinsp;0.02072, P\u0026thinsp;=\u0026thinsp;0.032). The rectoanal gradient and manometric defecation index were inversely correlated with the MTV (r=-0.2226, P\u0026thinsp;=\u0026thinsp;0.021, and r=-0.2158, P\u0026thinsp;=\u0026thinsp;0.026, respectively). In rectal cancer patients after surgery, the rectoanal gradient and manometric defecation index were also inversely correlated with MTV (r=-0.3924, P\u0026thinsp;=\u0026thinsp;0.035, and r=-0.4214, P\u0026thinsp;=\u0026thinsp;0.023, respectively). (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eConsidering the distinct age and gender distribution among patients with various anorectal diseases, we aim to investigate whether these two factors exert influence on the correlation between rectal sensation and motility. Among patients with constipation, the rectoanal gradient and manometric defecation index showed inverse correlations with the FCSV (R\u0026sup2;=0.023, P\u0026thinsp;=\u0026thinsp;0.039, and R\u0026sup2;=0.01936, P\u0026thinsp;=\u0026thinsp;0.033, respectively) in middle-aged females, with only the rectoanal gradient showing an inverse correlation with the FCSV (R\u0026sup2;=0.0301, P\u0026thinsp;=\u0026thinsp;0.018) in elderly females. Additionally, the rectoanal gradient was inversely related to the DDV (R\u0026sup2;=0.02266, P\u0026thinsp;=\u0026thinsp;0.040) in middle-aged females, while both the rectoanal gradient and manometric defecation index demonstrated inverse correlations with the DDV (R\u0026sup2;=0.01829, P\u0026thinsp;=\u0026thinsp;0.039, and R\u0026sup2;=0.02376, P\u0026thinsp;=\u0026thinsp;0.036, respectively) in elderly females. Moreover, the rectoanal gradient was inversely correlated with the MTV (R\u0026sup2;=0.04384, P\u0026thinsp;=\u0026thinsp;0.025) in young females, and the maximum squeezing pressure showed a positive correlation with the MTV (R\u0026sup2;=0.02921, P\u0026thinsp;=\u0026thinsp;0.027) in elderly females. Notably, the constipated patients in the middle-aged and elderly groups exhibited a stronger correlation between rectal sensation and motility within the FCSV group compared to the DDV group (R\u0026sup2;=0.023 VS R\u0026sup2;=0.02266, and R\u0026sup2;=0.01936 VS R\u0026sup2;=0.01829, respectively). All male patients with rectal cancer were in the middle-aged group, and their maximum squeezing pressure was positively correlated with MTV (R\u0026sup2;=0.06153, P\u0026thinsp;=\u0026thinsp;0.040). Conversely, in elderly female patients with rectal cancer, the manometric defecation index was inversely correlated with the MTV (R\u0026sup2;=0.08826, P\u0026thinsp;=\u0026thinsp;0.013). (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIntact rectal sensation, which is maintained by the normal functioning of rectal afferent nerves and the rectal wall, leads to the sensation of defecatory urge [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Abnormalities in rectal sensation have been postulated as a potential pathophysiological mechanism in anorectal disorders. Thiruppathy et al. demonstrated that patients with urge FI and constipation exhibit relatively distinct rectal sensation profiles [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Based on the above research, we are also interested in investigating rectal sensation in patients with rectal cancer, as well as in postoperative patients exhibiting symptoms of anorectal disorders. Due to the reduced maximum tolerable volume and rectal compliance in postoperative patients, a small amount of content can trigger the defecatory urge, necessitating frequent defecation [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. This structural damage significantly affects the quality of life, resulting in significantly elevated rectal sensation thresholds compared to other diseases. Ihnat et al. found that patients who have undergone rectal cancer surgery often experience alterations in rectal sensitivity, typically accompanied by mild to moderate anorectal disorders, characterized by decreased anal resting and maximum squeezing pressures, as well as reduced rectal volume and compliance [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Therefore, we anticipate that exploring the relationship between rectal sensation and motility will shed light on the underlying pathophysiological mechanisms of various anorectal diseases, thereby enhancing diagnostic precision and therapeutic strategies. One or even two abnormal rectal sensory threshold volumes were found in most anorectal disorders through rectal sensory testing, and it is speculated that each sensory threshold volume may represent different pathophysiological pathways [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. In this study, we attempted to classify patients into sensitive and insensitive groups based on the same sensory threshold volumes to analyze rectal motility. According to the London Classification, the determination of rectal sensory abnormalities requires comparison with established normal values [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], however, determining the precise range for a normal threshold remains a challenge. In the healthy population, females exhibit significantly lower rectal sensory thresholds than males [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], and these thresholds tend to decrease with the increase of age [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Additionally, BMI has been identified as a factor influencing rectal sensory thresholds [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe sensation of rectal fullness induces the relaxation of the internal anal sphincter and the contraction of the external anal sphincter, which are crucial stages in the defecation process [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Fox et al. found that the first sensation occurs when the function of the internal anal sphincter is threatened, and the urge to defecate emerges as the function of the external anal sphincter is threatened [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Nevertheless, the precise correlation between rectal motility and sensation in anorectal disorders is not yet clear.\u003c/p\u003e \u003cp\u003ePatients with anorectal disorders often experience weak propulsive forces, heightened resistance during defecation, or both. Moreover, a long term negative anorectal gradient and anorectal dyssynergia can aggravate symptoms [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Training in the coordinated contraction of pelvic floor muscles and the relaxation of the anal sphincters to facilitate rectal evacuation has been demonstrated to enhance rectal sensation [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Our study found that patients in the insensitivity group exhibited elevated anal resting pressure and maximum squeezing pressure, as well as dyssynergic defecation and inadequate propulsive efforts, which is consistent with characteristics observed in constipated patients with rectal hyposensitivity in previous research [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. In addition, the constipated patients with rectal hyposensitivity require a greater volume to trigger the anorectal contraction reflex [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Some patients who lack the urge to defecate often actively increase abdominal pressure in an attempt to defecate, which can lead to uncoordinated movement of the pelvic floor muscles during this process. Proper guidance and training can help these patients establish good defecation habits, thereby enhancing their rectal sensation to some degree [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e Rectal motility varies according to different rectal sensations. Following the insertion of a balloon filled with an appropriate volume into the rectum of constipated patients with normal rectal sensation, an increase in the rectoanal gradient, correction of dyssynergic defecation, and improvements in the patients\u0026rsquo; symptoms were observed. However, stimulation patients with decreased rectal sensitivity using the same method did not result in any improvement [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Moreover, we observed that all three rectal sensory threshold volumes in constipated patients were significantly correlated with rectal motility. All of these correlations indicated that as sensory threshold volumes increased, the maximum squeezing pressure of patients increased, while the rectoanal gradient and manometric defecation index both decreased. This correlation was weaker in rectal cancer and postoperative patients, and it was only found in the MTV. These findings suggest that different diseases possess unique characteristics that may facilitate diagnosis and therapeutic advancements in the future.\u003c/p\u003e \u003cp\u003eIn Jiang et al. research, DDV was elevated in all hyposensitivity functional anorectal disorder patients, and it was speculated as a useful indicator for the diagnosis of rectal sensation impairment [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. However, our findings revealed that each sensory threshold volume in constipated patients exhibited significant correlations with motility, with FCSV showing the most pronounced correlation. Therefore, we speculate that FCSV may be the most reliable indicator for assessing rectal sensory impairment and predicting motor function performance. Similarly, in our study, only MTV was significantly correlated with rectal motility in rectal cancer patients and postoperative patients, suggesting that MTV may be the best predictive indicator for both groups.\u003c/p\u003e \u003cp\u003eAge and gender play significant roles in rectal sensation and motility. Rectal sensory threshold volumes tend to increase with advancing age, particularly in males [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e], whereas motility tends to decline with age, more prominently in females [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Noelting et al. reported that healthy older women exhibit a greater rectoanal gradient than younger women [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Conversely, our research found that, under the same FCSV and DDV, middle-aged female patients with constipation have a higher rectoanal gradient than elderly female patients. Consequently, the influence of age and gender on this correlation is still uncertain. Furthermore, we observed that in middle-aged and elderly female patients with constipation, FCSV had a more pronounced effect on the rectoanal gradient than DDV. Overall, although the influence of age and gender on these correlations is limited, it remains significant and should not be overlooked, in order to better understand and treat anorectal diseases in clinical practice.\u003c/p\u003e \u003cp\u003eThis study is constrained by its retrospective design and the varying number of subjects across the different disease categories. In addition, our study focused solely on the correlation between rectal sensation and rectal motility. However, it is important to note that sensory afferent nerve terminals involved in defecation are present not only in the rectum but also in the anal canal, and their functions are not entirely identical [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. Both patients with rectal hyposensitivity and normal sensation may present with abnormal anal canal sensation [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. The interplay between rectal sensation, anal canal sensation, and their respective correlations with motility requires further investigation.\u003c/p\u003e \u003cp\u003eIn conclusion, our data indicate that various anorectal disorders present unique profiles of rectal sensation and motility, among which postoperative rectal cancer patients demonstrating the highest rectal sensitivity. Patients with constipation exhibit differences in rectal motility among all three rectal sensory conditions, and the rectal motility of rectal cancer and postoperative patients only show differences in MTV. In patients with constipation, both the rectoanal pressure gradient and the manometric defecation index decrease as the three rectal sensory threshold volumes increase. Rectal cancer and postoperative patients exhibited clinical manifestations similar to those of constipated patients, but these similarities were only observed under the MTV. This study not only revealed the differences in rectal sensation among anorectal disorders but also provided insights for improving rectal motility and diagnosing diseases, thereby laying the foundation for the development of individualized treatment for patients.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFinancial support:\u003c/strong\u003e This work was supported by\u0026nbsp;Liaoning Revitalization Talents Program\u0026nbsp;(No.\u0026nbsp;XLYC2007028).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting Interests:\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eNone\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval:\u003c/strong\u003e All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The study was approved by the\u0026nbsp;ethics review committee of Xinhua Hospital Affiliated to Dalian University\u0026nbsp;(No.2023-93-01).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate:\u003c/strong\u003e Informed consent was obtained from all individual participants included in the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets generated or analyzed during the study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eXinpeng Wang conducted data analysis and wrote the draft of the manuscript. Yanhui Gao, Li Xiao, Shuang Wang and Bohong Xu contributed to data collection and interpretation. Yu Zhi designed and supervised the experiments, and performed critical revisions of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSupplementary Materials\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTo access the additional data provided in Supplementary Table 2, as well as the additional data and statistical information without significant correlations, please refer to the online version of the International Journal of Colorectal Disease.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eBharucha AE (2006) Pelvic floor: anatomy and function. Neurogastroenterol Motil 18:507\u0026ndash;519\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSharma A, Herekar A, Yan Y, Karunaratne T, Rao SSC (2022) Dyssynergic Defecation and Other Evacuation Disorders. 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J Anus Rectum Colon 7:74\u0026ndash;81\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGundling F, Seidl H, Scalercio N, Schmidt T, Schepp W, Pehl C (2010) Influence of gender and age on anorectal function: normal values from anorectal manometry in a large caucasian population. Digestion 81:207\u0026ndash;213\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNoelting J, Ratuapli SK, Bharucha AE, Harvey DM, Ravi K, Zinsmeister AR (2012) Normal values for high-resolution anorectal manometry in healthy women: effects of age and significance of rectoanal gradient. Am J Gastroenterol 107:1530\u0026ndash;1536\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKnowles CH (2018) Human studies of anorectal sensory function. Ir J Med Sci 187:1143\u0026ndash;1147\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVasudevan SP, Scott SM, Gladman MA, Lunniss PJ (2007) Rectal hyposensitivity: evaluation of anal sensation in female patients with refractory constipation with and without faecal incontinence. Neurogastroenterol Motil 19:660\u0026ndash;667\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"rectal sensation, rectal motility, anorectal disorders, high-resolution anorectal manometry","lastPublishedDoi":"10.21203/rs.3.rs-4657186/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4657186/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAltered rectal sensation and motility are prevalent in various anorectal disorders. However, the correlation between rectal sensation and motility has not been well-defined. The aims of this study are to determine the association between these two factors in anorectal disorders and to clarify the underlying mechanisms, thereby offering innovative insights for therapeutic approaches.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRetrospectively, we evaluated clinical data from 954 patients with anorectal disorders, who underwent high-resolution anorectal manometry for rectal motility and sensory testing. Regression analysis was performed to evaluate the associations between the rectal sensation and motility across different age and gender strata within different diseases.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSignificant variations in rectal sensations were observed across different diseases, with patients who had undergone rectal cancer surgery exhibiting the lowest sensory threshold volumes (P \u0026lt; 0.01). The constipated patients exhibited significant correlations between rectal sensory thresholds and motility (P \u0026lt; 0.001), with positive associations with maximum squeezing pressure and negative associations with rectoanal gradient and manometric defecation index. For rectal cancer and postoperative patients, only the maximum tolerable volume showed correlation with rectal motility (P \u0026lt; 0.05), including anal resting pressure, rectoanal gradient, and manometric defecation index. Regression analysis revealed that age and gender had a limited impact on the correlation between rectal sensation and motility.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePatients with anorectal diseases exhibit substantial variations in rectal sensation and motility, with a significant correlation observed between these factors. The correlation is notably influenced by age and gender in patients with constipation and rectal cancer, suggesting that similar relationships may be observed across various anorectal disorders.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRegistration number \u003c/strong\u003eChiCTR2400086148\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eReg Date \u003c/strong\u003e2024-06-26 00:00:00\u003c/p\u003e","manuscriptTitle":"Rectal Sensory-Motor Alterations: A Clinical Perspective on Anorectal Disorders","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-07-23 13:05:08","doi":"10.21203/rs.3.rs-4657186/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"e8e636a3-1bef-4840-b208-c7e36764d3d1","owner":[],"postedDate":"July 23rd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-01-07T08:54:18+00:00","versionOfRecord":[],"versionCreatedAt":"2024-07-23 13:05:08","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4657186","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4657186","identity":"rs-4657186","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}