Assessing Surgical Site Infection Risks in Posterior Cervical Decompression: The Role of Local Fat Thickness

Assessing Surgical Site Infection Risks in Posterior Cervical Decompression: The Role of Local Fat Thickness | 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 Assessing Surgical Site Infection Risks in Posterior Cervical Decompression: The Role of Local Fat Thickness B. Younes, J. Farzullayev, L. Kawish, D. Mielke, V. Rohde, Tammam Abboud This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6572326/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: Local subcutaneous fat thickness has been identified as a significant predictor for the risk of surgical site infection (SSI) in lumbar spine procedures. Emerging research suggests its potential relevance in posterior cervical spine surgery as well. This study aims to further explore the connection, focusing on the comparative impact of Body Mass Index (BMI) and localized fat thickness at the C5 level on the risk of SSIs. Methods: This study presents a comprehensive retrospective analysis of patients treated with posterior cervical decompression without fusion for mono- or multisegmental cervical spondylotic myelopathy. From 2015 to 2022. Exclusions were made for minors and individuals who received posterior cervical instrumentation. Measurements of localized nuchal and fat thickness at the C5 level were taken. Patient charts provided data on demographics, BMI, diabetic status, smoking history, previous surgical history, the extent of surgery (number of operated levels), and duration of hospital stay. A combination of univariate and multivariate analysis was employed to identify significant predictors of SSIs. Results: From the 346 patients who qualified for the study, 20 (5.8%) experienced SSIs. Those with SSIs generally had higher BMIs (median 29 vs. 27, p=0.032), greater nuchal fat thickness (median 27mm vs. 23mm, p=0.012), and more extensive surgeries (75% had multiple levels operated compared to 55% in the non-SSI cohort, p=0.001). Additionally, the occurrence of SSI resulted in a prolonged hospital stay (median 12 days vs. 7 days, p≤0.001). However, in multivariate logistic regression, nuchal fat thickness was not a significant predictor, whereas BMI and the number of operated levels were confirmed as substantial predictors of SSI (OR=1.095, CI: 1.005 to 1.192, p= 0.038 and OR=2.089, CI: 1.3 to 3.357, p= 0.002 respectively). Conclusion: This research indicates that contrary to initial assumptions, localized fat thickness at the C5 level is not a significant predictive factor for SSI post posterior cervical decompression. Instead, it underscores the importance of BMI and the extent of surgical intervention as considerable, quantifiable risk factors for SSIs. These findings can guide more effective preoperative assessments and targeted interventions to mitigate SSI risks in posterior cervical decompression surgeries. SSI Posterior cervical decompression Postoperative complications Cervical spine Figures Figure 1 Figure 2 Figure 3 Introduction Surgical site infection (SSI) rates following spinal surgeries vary widely, with figures ranging from 1–7%. Notably, the incidence of SSI after posterior cervical spine surgery presents an even broader range, from 0.5–18.2%, as reported in various studies [ 1 – 5 ]. This rate is significantly higher compared to that of surgeries employing the anterior cervical approach. SSIs are associated with extended hospital stays, increased rates of readmission, and can quadruple healthcare costs. Identifying and understanding risk factors for SSI is crucial for developing and enhancing preventive measures aimed at reducing SSI incidence. Established risk factors include diabetes, prolonged operative times, obesity, smoking, significant blood loss, and immunosuppression. Previous research has established a clear link between higher body mass index (BMI) and the increased risk of SSI following abdominal and spinal surgeries. An elevated BMI often correlates with greater subcutaneous tissue thickness. However, BMI alone does not provide insights into the localized distribution of adipose tissue, which can be critical for surgical outcomes. This has led to the exploration of measuring subcutaneous tissue thickness at specific surgical sites. The rationale is that thicker subcutaneous layers may contribute to larger potential spaces post-wound closure, complicating surgical exposure and potentially increasing the risk of tissue necrosis, subsequently elevating SSI risk. Indeed, some studies have identified a positive correlation between increased peri-incisional subcutaneous fat thickness and the heightened risk of SSI following both posterior cervical and lumbar spine fusion surgeries [ 6 , 7 ]. However, the literature provides no data on the correlation between subcutaneous fat thickness and the risk of SSI in cases of posterior cervical surgery without additional fusion. The aim of this investigation is to evaluate the relationship between subcutaneous fat thickness, BMI, and other risk factors in relation to the risk of SSI following posterior cervical decompression for degenerative spine diseases, without the incorporation of fusion techniques. Methods This retrospective, single-center case series analyzed a cohort of 346 patients who underwent posterior cervical decompression without fusion for degenerative spine diseases at University Hospital Göttingen between 2015 and 2022. We collected and reviewed demographic, radiological, and clinical data pre- and post-surgery, focusing on identifying potential surgical site infection risk factors. The variables studied included age, gender, a history of diabetes, smoking status, ASA (American Society of Anesthesiologists) classification, prior surgeries on cervical spine, length of operation, the number of levels operated, and the number of days stayed postoperatively. We also analyzed the incidence of SSI, including the associated microorganisms. The height and weight of patients at the time of the index surgery were recorded to calculate their BMI. Cases involving fusion constructs from the occiput to C7 were excluded from the analysis. All participants had undergone preoperative magnetic resonance imaging (MRI) of the cervical spine. Patient identification for inclusion was done using concurrent ICD-10 codes specific to posterior cervical spine decompression. Unilateral cervical decompression was performed as described by Mielke & Rohde [ 8 ]. After a midline skin incision, the muscle fascia is incised, and muscle detached from the hemilamina(e). Depending on the number of involved segments, a laminotomy or hemilaminectomy is performed under the microscope. A 5-mm diamond drill is used to remove the base of the spinous process from the medial hemilaminectomy edge to the contralateral medial facet joint, thinning the inner contralateral hemilamina(e) without breaching the outer corticalis. The usually hypertrophic yellow ligament is removed with a Kerrison rongeur until the contralateral dorsal nerve root is exposed. The wound is closed routinely without suction drainage. SSIs were defined and categorized as superficial, deep, and organ/space infections occurring within 30 days post-surgery, following the guidelines set by the Centers for Disease Control and Prevention. Measurement of fat thickness For measuring subcutaneous fat and muscle thickness, we defined fat thickness as the distance from the C5 spinous processes to the back skin and maximum muscle thickness as the distance from the lamina to the spinous processes of C5. Nuchal thickness was subsequently calculated by adding these two measurements. All measurements were taken from axial and sagittal reformats in MRI scans and were standardized to ensure uniformity. Each measurement's accuracy was manually verified by two authors (B. Y. and J. F.). We also documented other risk factors for the development of SSI as part of our comprehensive data collection. Data management and statistical analysis Data capture was systematic and was entered into an Excel database (Microsoft Corp.). For the statistical analysis, the data were exported to SPSS and analyzed using IBM SPSS Statistics Version 27.0 (IBM Corp, Released 2016, IBM SPSS Statistics for Windows, Version 27.0, Armonk, NY, USA). We employed bivariate analysis to explore the associations between various patient characteristics (age, gender, diabetes status, smoking status, ASA classification, and BMI) and the development of SSI. Continuous variables such as age and BMI, which were normally distributed, were analyzed using the Student's t-test. Categorical variables like gender, diabetes status, and number of levels operated were analyzed using the chi-square test. Statistical significance was considered at a p-value of less than 0.05. Results The cohort's mean age was 65 years. Values if descriptive with a gender distribution of 65% male (n=225) and 35% female (n=121). Diabetes was present in 16.8% (n=58) of patients. The mean BMI was 27.8 ± 5.2 kg/m². Smoking was reported by 28.3% of the patients (n=98). Details of ASA classification, mean length of surgery and hospital stay are presented in Table 1. 195 patients (56%) received decompression of more than one level. Seven patients (2%) developed an epidural hematoma in the surgical access area, of which six underwent hematoma evacuation. Among the 346 patients, 20 (5.8%) developed SSI. All SSIs manifested within four weeks postoperatively and 16 already (80%) during hospital stay. Microbiologic cultures were obtained from all 20 patients diagnosed with SSIs (SSIs), with 12 individuals (60%) exhibiting positive cultures. Of the 20 patients with SSI, only 2 patients (10%) required second surgery for wound débridement. Staphylococcus aureus was identified in 8 cases (40%) of the positive cultures, and Staphylococcus epidermidis and Enterococcus spp. complex in 2 patients each. Management of SSI Conservative management of SSI failed in 17 of 20 patients (85%), who had to undergo wound debridement, while one of them (5%) had to be treated with additional VAC therapy. In the remaining three patients (15%), conservative management was successful. All patients received long-term antibiotic treatment in accordance with the results of antibiotic susceptibility testing. Analysis Patients who developed SSI did not differ from those who did not regarding age, gender, rate of diabetes, smoking status, ASA, prior surgeries on cervical spine or length of operation. Occurrence of epidural hematoma and its surgical treatment did not correlate with SSI (p= 0.995). Patients with SSIs generally had higher BMIs (median 29 vs. 27, p=0.032, Figure 1), greater nuchal fat thickness (median 27mm vs. 23mm, p=0.012, Figure 2), and more extensive surgeries, with a higher median number of operated levels in the SSI group (2.4) compared to the non-SSI group (1.75), whereas 75% of the SSI patients underwent more than one level of surgery, compared to 55% in the non-SSI group (p=0.001, Figure 3).The ratio of fat to muscle thickness was also higher in the SSI group (median 0.98 vs. 0.75, p=0.003). Additionally, the occurrence of SSI resulted in a prolonged hospital stay (median 12 days vs. 7 days, p≤0.001). All results of univariate analysis are presented in Table 2. In the multivariate logistic regression, neither nuchal fat thickness nor the ratio of fat to muscle thickness were significant predictors, whereas BMI and the number of operated levels were confirmed as substantial predictors of SSI (OR=1.095, CI: 1.005 to 1.192, p= 0.038 and OR=2.089, CI: 1.3 to 3.357, p= 0.002 respectively). All values are presented in Table 3. Discussion Surgical site infections represent a prevalent complication associated with spine surgery, thereby amplifying patient morbidity and mortality rates. In this study we presented a large series of patients who received posterior cervical decompression. A comprehensive analysis was conducted, investigating all factors that can be associated with SSI. Surgery related risk factors included number of operated levels and duration of surgery. Patients’ dependant risk factors included age, obesity, diabetes, smoking and ASA classification. Surgery related risk factors We found that number of operated levels was an independent factor predicting postoperative SSI. Patients who were operated on more than one level had a 2-fold higher risk of developing SSI. Although the correlation between number of fused levels and SSI has been reported before [ 9 ], our study is the first to highlight this risk during decompression surgery. Duration of surgery which is one of the known risk factors for SSI was not found to be significant in the context of dorsal cervical compression. This can be attributed to the relatively short surgery duration compared with fusion surgery. Another known risk factor is blood loss [ 10 ]. Estimated blood loss over 1 liter was reported to increase risk of SSI in spine surgery [ 11 ]. We did not address this aspect in our study, as blood loss during dorsal cervical decompression is unlikely to exceed the limit of one liter. We also assessed the frequency of an operation-associated spinal epidural hematoma. Its occurrence rate was as low as 2% and did not correlate with SSI. Patients’ dependant risk factors, BMI or fat-index? SSI in general might be associated with several patient characteristics including age, smoking, diabetes, obesity and previous surgeries. However, only few of these factors were reported to be of significance in the context of dorsal cervical surgery. Obesity expressed by BMI or nuchal thickness was the most frequently reported factor to be associated with SSI among multiple studies addressing dorsal cervical spine surgery [ 7 , 12 – 17 ]. In posterior cervical fusion surgery, studies with large patient cohorts confirmed BMI as a clear risk factor for SSI [ 12 , 16 ]. However, current literature indicated that local fat distribution may have higher impact on SSI than general obesity in patients undergoing lumbar surgery [ 18 , 19 ], and recent series suggested that increased surgical site subcutaneous fat thickness [ 13 ] and precisely increase fat-index [ 15 , 17 ] are associated with higher risk of SSI following cervical spine surgery. Our results do not support this suggestion. Although each of fat index and fat thickness together with BMI correlated with SSI in the univariate analysis, only BMI among Patients’ related risk factors was an independent predictor of SSI. This can be explained by the close relationship between BMI, fat thickness and fat index as the first directly influences the last two factors. Our series is important as it addresses a specific surgical approach namely, unilateral cervical decompression, while most studies included dorsal cervical fusion with or without laminectomy. We found an SSI rate of 6%, which lies within the range of reported SSI rates in the literature of 4–11%[ 7 , 12 , 13 , 15 ]. Our results indicate that the less invasive surgical approach does not reduce risk of SSI in comparison to other dorsal cervical spine approaches and that BMI is the decisive factor among patient’ related risk factors to be considered when counseling patients regarding postoperative SSI. Medical vs. surgical treatment of SSI Medical treatment was applied in all patients suffering from SSI in this series. However, revision surgery was required in most cases (85%). Similarly high rate of repeated surgery for treatment of SSI were reported previously (3). This suggests that earlier surgical intervention to treat SSI following dorsal cervical decompression is superior to medical treatment and encourages earlier surgical intervention to avoid longer hospital stays and in-hospital complications. However, larger studies will be needed to clarify the question of the optimal time of surgical intervention for treatment of SSI. Conclusion The study concludes that the risk of surgical site infection (SSI) in posterior cervical decompressions increases in correlation with the number of operated levels and high BMI. Notably, the analysis did not reveal a significant association between FT/MT, nuchal fat thickness, and the incidence of SSIs. Declarations a. Funding: The authors declare that no funds, grants, or other financial support were received during the preparation of this manuscript. b. Conflicts of interest/Competing interests: The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper. c. Ethics approval and consent to participate: Ethical approval was obtained (ethical commission of University Hospital Göttingen, Internal Review Board reference number: 12/09/23), aligning with the 1964 Declaration of Helsinki and its amendments. All procedures adhered to local and institutional laws and data protection regulations. Informed consent was not required as the study was retrospective in nature and involved the analysis of previously collected data. d. Clinical trial number: Not applicable. e. Availability of data and materials: The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request. f. Consent for publication: For this retrospective study, formal consent for publication was not required, as all data were anonymized and collected in accordance with institutional ethical standards and national data protection regulations. g. Authors' contributions: TA: designed the project, analysed data, made the figure and corrected the manuscript. BY: wrote the manuscript and analysed data. JF: wrote the manuscript and analysed data. LK: analysed data. DM: provided scientific support, and corrected the manuscript. VR: designed the project, provided scientific support and corrected the manuscript. All authors fulfil the criteria for authorship of the International Committee of Medical Journal Editors. h. Acknowledgement: Not applicable. References Kwon BK, Fisher CG, Boyd MC, Cobb J, Jebson H, Noonan V, et al. A prospective randomized controlled trial of anterior compared with posterior stabilization for unilateral facet injuries of the cervical spine. J Neurosurg Spine 2007;7(1):1-12. Memtsoudis SG, Hughes A, Ma Y, Chiu YL, Sama AA, Girardi FP. Increased in-hospital complications after primary posterior versus primary anterior cervical fusion. Clin Orthop Relat Res 2011;469(3):649-57. Olsen MA, Mayfield J, Lauryssen C, Polish LB, Jones M, Vest J, et al. Risk factors for surgical site infection in spinal surgery. Journal of neurosurgery 2003;98(2 Suppl):149-55. Sebastian A, Huddleston P, 3rd, Kakar S, Habermann E, Wagie A, Nassr A. Risk factors for surgical site infection after posterior cervical spine surgery: an analysis of 5,441 patients from the ACS NSQIP 2005-2012. Spine J 2016;16(4):504-9. Xu R, Bydon M, Sciubba DM, Witham TF, Wolinsky JP, Gokaslan ZL, et al. Safety and efficacy of rhBMP2 in posterior cervical spinal fusion for subaxial degenerative spine disease: Analysis of outcomes in 204 patients. Surgical neurology international 2011;2:109. Gupta VK, Zhou Y, Manson JF, Watt JP. Radiographic spine adipose index: an independent risk factor for deep surgical site infection after posterior instrumented lumbar fusion. Spine J 2021;21(10):1711-7. Mehta AI, Babu R, Sharma R, Karikari IO, Grunch BH, Owens TR, et al. Thickness of subcutaneous fat as a risk factor for infection in cervical spine fusion surgery. The Journal of bone and joint surgery American volume 2013;95(4):323-8. Mielke D, Rohde V. Bilateral spinal canal decompression via hemilaminectomy in cervical spondylotic myelopathy. Acta Neurochir (Wien) 2015;157(10):1813-7. Zhang X, Liu P, You J. Risk factors for surgical site infection following spinal surgery: A meta-analysis. Medicine 2022;101(8):e28836. Aeschbacher P, Nguyen TL, Dorn P, Kocher GJ, Lutz JA. Surgical Site Infections Are Associated With Higher Blood Loss and Open Access in General Thoracic Practice. Front Surg 2021;8:656249. Pull ter Gunne AF, Cohen DB. Incidence, prevalence, and analysis of risk factors for surgical site infection following adult spinal surgery. Spine 2009;34(13):1422-8. Cheng CW, Cizik AM, Dagal AHC, Lewis L, Lynch J, Bellabarba C, et al. Body mass index and the risk of deep surgical site infection following posterior cervical instrumented fusion. Spine J 2019;19(4):602-9. Donnally CJ, Henstenburg JM, Pezzulo JD, Farronato D, Patel PD, Sherman M, et al. Increased Surgical Site Subcutaneous Fat Thickness Is Associated with Infection after Posterior Cervical Fusion. Surg Infect (Larchmt) 2022;23(4):364-71. Fatima N, Massaad E, Alvarez-Breckenridge C, Berry Candelario JE, Hadzipasic M, Shankar GM, et al. Does Obesity Correlate with Postoperative Complications After Elective Posterior Cervical Spine Fusion? World neurosurgery 2020;141:e231-e8. Porche K, Lockney DT, Gooldy T, Kubilis P, Murad G. Nuchal thickness and increased risk of surgical site infection in posterior cervical operations. Clinical neurology and neurosurgery 2021;205:106653. Sridharan M, Malik AT, Kim J, Khan SN, Yu E. Does Increasing Body Mass Index Correlate with Adverse Outcomes Following Posterior Cervical Fusions? World neurosurgery 2020;133:e789-e95. Wang J, Chang Y, Suo M, Huang H, Liu X, Li Z. Incidence and risk factors of surgical site infection following cervical laminoplasty: A retrospective clinical study. Int Wound J 2023;21(2). Lee JJ, Odeh KI, Holcombe SA, Patel RD, Wang SC, Goulet JA, et al. Fat Thickness as a Risk Factor for Infection in Lumbar Spine Surgery. Orthopedics 2016;39(6):e1124-e8. Sang C, Chen X, Ren H, Meng Z, Jiang J, Qin Y. Correlation between lumbar multifidus fat infiltration and lumbar postoperative infection: a retrospective case-control study. BMC Surg 2020;20(1):35. Tables Tables 1 to 3 are available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Table1.docx Table2.docx Table3.docx 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-6572326","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":465435935,"identity":"f8f322f5-643d-4b1e-9c53-875110aaf785","order_by":0,"name":"B. Younes","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA6UlEQVRIiWNgGAWjYBACA2bmBoYHFf8YGNgbQFwLYrQwNjAknDnAwMBzAMSVIEILA1BLYhtQuUQCiE+EFnN2xsYPCWfu2BvcfH51w48CCQb+9u4EvFosmxmbJRIqniVuuJ1TdrMH6DCJM2c34HfYYcYGiYQzzAkGt3PSbvAAtRhI5BLU0vwjsY0Z6LAzaTf/EKmlTSKx7TDjhhvsx24TZQvQL20WCWfSEmeeyWG7LWMgwUPQL+b8hw/f+FBhY893/Pizm2/+2Mjxt/fi1wIHCgd4DEA0D3HKQUC+gf0B8apHwSgYBaNgRAEAcYRPkfj+Om0AAAAASUVORK5CYII=","orcid":"","institution":"University medical center Göttingen","correspondingAuthor":true,"prefix":"","firstName":"B.","middleName":"","lastName":"Younes","suffix":""},{"id":465435936,"identity":"14ff5ea3-a372-47e9-9fcf-08a517d1783d","order_by":1,"name":"J. 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Notably, the incidence of SSI after posterior cervical spine surgery presents an even broader range, from 0.5\u0026ndash;18.2%, as reported in various studies [\u003cspan additionalcitationids=\"CR2 CR3 CR4\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. This rate is significantly higher compared to that of surgeries employing the anterior cervical approach. SSIs are associated with extended hospital stays, increased rates of readmission, and can quadruple healthcare costs. Identifying and understanding risk factors for SSI is crucial for developing and enhancing preventive measures aimed at reducing SSI incidence. Established risk factors include diabetes, prolonged operative times, obesity, smoking, significant blood loss, and immunosuppression.\u003c/p\u003e \u003cp\u003ePrevious research has established a clear link between higher body mass index (BMI) and the increased risk of SSI following abdominal and spinal surgeries. An elevated BMI often correlates with greater subcutaneous tissue thickness. However, BMI alone does not provide insights into the localized distribution of adipose tissue, which can be critical for surgical outcomes. This has led to the exploration of measuring subcutaneous tissue thickness at specific surgical sites. The rationale is that thicker subcutaneous layers may contribute to larger potential spaces post-wound closure, complicating surgical exposure and potentially increasing the risk of tissue necrosis, subsequently elevating SSI risk. Indeed, some studies have identified a positive correlation between increased peri-incisional subcutaneous fat thickness and the heightened risk of SSI following both posterior cervical and lumbar spine fusion surgeries [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, the literature provides no data on the correlation between subcutaneous fat thickness and the risk of SSI in cases of posterior cervical surgery without additional fusion.\u003c/p\u003e \u003cp\u003eThe aim of this investigation is to evaluate the relationship between subcutaneous fat thickness, BMI, and other risk factors in relation to the risk of SSI following posterior cervical decompression for degenerative spine diseases, without the incorporation of fusion techniques.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis retrospective, single-center case series analyzed a cohort of 346 patients who underwent posterior cervical decompression without fusion for degenerative spine diseases at University Hospital G\u0026ouml;ttingen between 2015 and 2022. We collected and reviewed demographic, radiological, and clinical data pre- and post-surgery, focusing on identifying potential surgical site infection risk factors. The variables studied included age, gender, a history of diabetes, smoking status, ASA (American Society of Anesthesiologists) classification, prior surgeries on cervical spine, length of operation, the number of levels operated, and the number of days stayed postoperatively. We also analyzed the incidence of SSI, including the associated microorganisms. The height and weight of patients at the time of the index surgery were recorded to calculate their BMI. Cases involving fusion constructs from the occiput to C7 were excluded from the analysis.\u003c/p\u003e \u003cp\u003eAll participants had undergone preoperative magnetic resonance imaging (MRI) of the cervical spine. Patient identification for inclusion was done using concurrent ICD-10 codes specific to posterior cervical spine decompression. Unilateral cervical decompression was performed as described by Mielke \u0026amp; Rohde [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. After a midline skin incision, the muscle fascia is incised, and muscle detached from the hemilamina(e). Depending on the number of involved segments, a laminotomy or hemilaminectomy is performed under the microscope. A 5-mm diamond drill is used to remove the base of the spinous process from the medial hemilaminectomy edge to the contralateral medial facet joint, thinning the inner contralateral hemilamina(e) without breaching the outer corticalis. The usually hypertrophic yellow ligament is removed with a Kerrison rongeur until the contralateral dorsal nerve root is exposed. The wound is closed routinely without suction drainage. SSIs were defined and categorized as superficial, deep, and organ/space infections occurring within 30 days post-surgery, following the guidelines set by the Centers for Disease Control and Prevention.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eMeasurement of fat thickness\u003c/h2\u003e \u003cp\u003eFor measuring subcutaneous fat and muscle thickness, we defined fat thickness as the distance from the C5 spinous processes to the back skin and maximum muscle thickness as the distance from the lamina to the spinous processes of C5. Nuchal thickness was subsequently calculated by adding these two measurements. All measurements were taken from axial and sagittal reformats in MRI scans and were standardized to ensure uniformity. Each measurement's accuracy was manually verified by two authors (B. Y. and J. F.). We also documented other risk factors for the development of SSI as part of our comprehensive data collection.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eData management and statistical analysis\u003c/h3\u003e\n\u003cp\u003eData capture was systematic and was entered into an Excel database (Microsoft Corp.). For the statistical analysis, the data were exported to SPSS and analyzed using IBM SPSS Statistics Version 27.0 (IBM Corp, Released 2016, IBM SPSS Statistics for Windows, Version 27.0, Armonk, NY, USA).\u003c/p\u003e \u003cp\u003eWe employed bivariate analysis to explore the associations between various patient characteristics (age, gender, diabetes status, smoking status, ASA classification, and BMI) and the development of SSI. Continuous variables such as age and BMI, which were normally distributed, were analyzed using the Student's t-test. Categorical variables like gender, diabetes status, and number of levels operated were analyzed using the chi-square test. Statistical significance was considered at a p-value of less than 0.05.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThe cohort's mean age was 65 years. Values if descriptive with a gender distribution of 65% male (n=225) and 35% female (n=121). Diabetes was present in 16.8% (n=58) of patients. The mean BMI was 27.8 ± 5.2 kg/m². Smoking was reported by 28.3% of the patients (n=98). Details of ASA classification, mean length of surgery and hospital stay are presented in Table 1. \u0026nbsp;195 patients (56%) received decompression of more than one level. Seven patients (2%) developed an epidural hematoma in the surgical access area, of which six underwent hematoma evacuation.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;Among the 346 patients, 20 (5.8%) developed SSI. All SSIs manifested within four weeks postoperatively and 16 already (80%) during hospital stay. \u0026nbsp;Microbiologic cultures were obtained from all 20 patients diagnosed with SSIs (SSIs), with 12 individuals (60%) exhibiting positive cultures. Of the 20 patients with SSI, only 2 patients (10%) required second surgery for wound débridement. Staphylococcus aureus was identified in 8 cases (40%) of the positive cultures, and Staphylococcus epidermidis and Enterococcus spp. complex in 2 patients each.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eManagement of SSI\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eConservative management of SSI failed in 17 of 20 patients (85%), who had to undergo wound debridement, while one of them (5%) had to be treated with additional VAC therapy. In the remaining three patients (15%), conservative management was successful.\u0026nbsp;All patients received long-term antibiotic treatment in accordance with the results of antibiotic susceptibility testing.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAnalysis\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003ePatients who developed SSI did not differ from those who did not regarding age, gender, rate of diabetes, smoking status, ASA, prior surgeries on cervical spine or length of operation. Occurrence of epidural hematoma and its surgical treatment did not correlate with SSI (p= 0.995).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePatients with SSIs generally had higher BMIs (median 29 vs. 27, p=0.032, Figure 1), greater nuchal fat thickness (median 27mm vs. 23mm, p=0.012, Figure 2), and more extensive surgeries, with a higher median number of operated levels in the SSI group (2.4) compared to the non-SSI group (1.75), whereas 75% of the SSI patients underwent more than one level of surgery, compared to 55% in the non-SSI group (p=0.001, Figure 3).The ratio of fat to muscle thickness was also higher in the SSI group (median 0.98 vs. 0.75, p=0.003). Additionally, the occurrence of SSI resulted in a prolonged hospital stay (median 12 days vs. 7 days, p≤0.001). \u0026nbsp;All results of univariate analysis are presented in Table 2.\u003c/p\u003e\n\u003cp\u003eIn the multivariate logistic regression, neither nuchal fat thickness nor the ratio of fat to muscle thickness were significant predictors, whereas BMI and the number of operated levels were confirmed as substantial predictors of SSI (OR=1.095, CI: 1.005 to 1.192, p= 0.038 and OR=2.089, CI: 1.3 to 3.357, p= 0.002 respectively). All values are presented in Table 3.\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eSurgical site infections represent a prevalent complication associated with spine surgery, thereby amplifying patient morbidity and mortality rates. In this study we presented a large series of patients who received posterior cervical decompression. A comprehensive analysis was conducted, investigating all factors that can be associated with SSI. Surgery related risk factors included number of operated levels and duration of surgery. Patients’ dependant risk factors included age, obesity, diabetes, smoking and ASA classification.\u003c/p\u003e\n\u003ch3\u003eSurgery related risk factors\u003c/h3\u003e\n\u003cp\u003eWe found that number of operated levels was an independent factor predicting postoperative SSI. Patients who were operated on more than one level had a 2-fold higher risk of developing SSI. Although the correlation between number of fused levels and SSI has been reported before [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e], our study is the first to highlight this risk during decompression surgery.\u003c/p\u003e \u003cp\u003eDuration of surgery which is one of the known risk factors for SSI was not found to be significant in the context of dorsal cervical compression. This can be attributed to the relatively short surgery duration compared with fusion surgery. Another known risk factor is blood loss [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Estimated blood loss over 1 liter was reported to increase risk of SSI in spine surgery [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. We did not address this aspect in our study, as blood loss during dorsal cervical decompression is unlikely to exceed the limit of one liter. We also assessed the frequency of an operation-associated spinal epidural hematoma. Its occurrence rate was as low as 2% and did not correlate with SSI.\u003c/p\u003e\n\u003ch3\u003ePatients’ dependant risk factors, BMI or fat-index?\u003c/h3\u003e\n\u003cp\u003eSSI in general might be associated with several patient characteristics including age, smoking, diabetes, obesity and previous surgeries. However, only few of these factors were reported to be of significance in the context of dorsal cervical surgery. Obesity expressed by BMI or nuchal thickness was the most frequently reported factor to be associated with SSI among multiple studies addressing dorsal cervical spine surgery [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan additionalcitationids=\"CR13 CR14 CR15 CR16\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e–\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. In posterior cervical fusion surgery, studies with large patient cohorts confirmed BMI as a clear risk factor for SSI [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. However, current literature indicated that local fat distribution may have higher impact on SSI than general obesity in patients undergoing lumbar surgery [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], and recent series suggested that increased surgical site subcutaneous fat thickness [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e] and precisely increase fat-index [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] are associated with higher risk of SSI following cervical spine surgery. Our results do not support this suggestion. Although each of fat index and fat thickness together with BMI correlated with SSI in the univariate analysis, only BMI among Patients’ related risk factors was an independent predictor of SSI. This can be explained by the close relationship between BMI, fat thickness and fat index as the first directly influences the last two factors.\u003c/p\u003e \u003cp\u003eOur series is important as it addresses a specific surgical approach namely, unilateral cervical decompression, while most studies included dorsal cervical fusion with or without laminectomy. We found an SSI rate of 6%, which lies within the range of reported SSI rates in the literature of 4–11%[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Our results indicate that the less invasive surgical approach does not reduce risk of SSI in comparison to other dorsal cervical spine approaches and that BMI is the decisive factor among patient’ related risk factors to be considered when counseling patients regarding postoperative SSI.\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eMedical vs. surgical treatment of SSI\u003c/h2\u003e \u003cp\u003eMedical treatment was applied in all patients suffering from SSI in this series. However, revision surgery was required in most cases (85%). Similarly high rate of repeated surgery for treatment of SSI were reported previously (3). This suggests that earlier surgical intervention to treat SSI following dorsal cervical decompression is superior to medical treatment and encourages earlier surgical intervention to avoid longer hospital stays and in-hospital complications. However, larger studies will be needed to clarify the question of the optimal time of surgical intervention for treatment of SSI.\u003c/p\u003e \u003cp\u003e\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe study concludes that the risk of surgical site infection (SSI) in posterior cervical decompressions increases in correlation with the number of operated levels and high BMI. Notably, the analysis did not reveal a significant association between FT/MT, nuchal fat thickness, and the incidence of SSIs.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cem\u003ea.\u0026nbsp; \u0026nbsp;\u003c/em\u003e\u003cem\u003eFunding:\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that no funds, grants, or other financial support were received during the preparation of this manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eb.\u0026nbsp; \u0026nbsp;\u003c/em\u003e\u003cem\u003eConflicts of interest/Competing interests:\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ec.\u0026nbsp; \u0026nbsp;\u003c/em\u003e\u003cem\u003eEthics approval and consent to participate:\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eEthical approval was obtained (ethical commission of University Hospital Göttingen, Internal Review Board reference number: 12/09/23), aligning with the 1964 Declaration of Helsinki and its amendments. All procedures adhered to local and institutional laws and data protection regulations. Informed consent was not required as the study was retrospective in nature and involved the analysis of previously collected data.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ed.\u0026nbsp; \u0026nbsp;\u003c/em\u003e\u003cem\u003eClinical trial number:\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ee.\u0026nbsp; \u0026nbsp;\u003c/em\u003e\u003cem\u003eAvailability of data and materials:\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ef.\u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/em\u003e\u003cem\u003eConsent for publication:\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eFor this retrospective study, formal consent for publication was not required, as all data were anonymized and collected in accordance with institutional ethical standards and national data protection regulations.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eg.\u0026nbsp; \u0026nbsp;\u003c/em\u003e\u003cem\u003eAuthors' contributions:\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eTA: designed the project, analysed data, made the figure and corrected the manuscript. BY: wrote the manuscript and analysed data. JF: wrote the manuscript and analysed data. LK: analysed data. DM: provided scientific support, and corrected the manuscript. VR: designed the project, provided scientific support and corrected the manuscript. All authors fulfil the criteria for authorship of the International Committee of Medical Journal Editors.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eh.\u0026nbsp; \u0026nbsp;\u003c/em\u003e\u003cem\u003eAcknowledgement:\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eKwon BK, Fisher CG, Boyd MC, Cobb J, Jebson H, Noonan V, et al. A prospective randomized controlled trial of anterior compared with posterior stabilization for unilateral facet injuries of the cervical spine. J Neurosurg Spine 2007;7(1):1-12.\u003c/li\u003e\n\u003cli\u003eMemtsoudis SG, Hughes A, Ma Y, Chiu YL, Sama AA, Girardi FP. Increased in-hospital complications after primary posterior versus primary anterior cervical fusion. Clin Orthop Relat Res 2011;469(3):649-57.\u003c/li\u003e\n\u003cli\u003eOlsen MA, Mayfield J, Lauryssen C, Polish LB, Jones M, Vest J, et al. Risk factors for surgical site infection in spinal surgery. Journal of neurosurgery 2003;98(2 Suppl):149-55.\u003c/li\u003e\n\u003cli\u003eSebastian A, Huddleston P, 3rd, Kakar S, Habermann E, Wagie A, Nassr A. Risk factors for surgical site infection after posterior cervical spine surgery: an analysis of 5,441 patients from the ACS NSQIP 2005-2012. Spine J 2016;16(4):504-9.\u003c/li\u003e\n\u003cli\u003eXu R, Bydon M, Sciubba DM, Witham TF, Wolinsky JP, Gokaslan ZL, et al. Safety and efficacy of rhBMP2 in posterior cervical spinal fusion for subaxial degenerative spine disease: Analysis of outcomes in 204 patients. Surgical neurology international 2011;2:109.\u003c/li\u003e\n\u003cli\u003eGupta VK, Zhou Y, Manson JF, Watt JP. Radiographic spine adipose index: an independent risk factor for deep surgical site infection after posterior instrumented lumbar fusion. Spine J 2021;21(10):1711-7.\u003c/li\u003e\n\u003cli\u003eMehta AI, Babu R, Sharma R, Karikari IO, Grunch BH, Owens TR, et al. Thickness of subcutaneous fat as a risk factor for infection in cervical spine fusion surgery. The Journal of bone and joint surgery American volume 2013;95(4):323-8.\u003c/li\u003e\n\u003cli\u003eMielke D, Rohde V. Bilateral spinal canal decompression via hemilaminectomy in cervical spondylotic myelopathy. Acta Neurochir (Wien) 2015;157(10):1813-7.\u003c/li\u003e\n\u003cli\u003eZhang X, Liu P, You J. Risk factors for surgical site infection following spinal surgery: A meta-analysis. Medicine 2022;101(8):e28836.\u003c/li\u003e\n\u003cli\u003eAeschbacher P, Nguyen TL, Dorn P, Kocher GJ, Lutz JA. Surgical Site Infections Are Associated With Higher Blood Loss and Open Access in General Thoracic Practice. Front Surg 2021;8:656249.\u003c/li\u003e\n\u003cli\u003ePull ter Gunne AF, Cohen DB. Incidence, prevalence, and analysis of risk factors for surgical site infection following adult spinal surgery. Spine 2009;34(13):1422-8.\u003c/li\u003e\n\u003cli\u003eCheng CW, Cizik AM, Dagal AHC, Lewis L, Lynch J, Bellabarba C, et al. Body mass index and the risk of deep surgical site infection following posterior cervical instrumented fusion. Spine J 2019;19(4):602-9.\u003c/li\u003e\n\u003cli\u003eDonnally CJ, Henstenburg JM, Pezzulo JD, Farronato D, Patel PD, Sherman M, et al. Increased Surgical Site Subcutaneous Fat Thickness Is Associated with Infection after Posterior Cervical Fusion. Surg Infect (Larchmt) 2022;23(4):364-71.\u003c/li\u003e\n\u003cli\u003eFatima N, Massaad E, Alvarez-Breckenridge C, Berry Candelario JE, Hadzipasic M, Shankar GM, et al. Does Obesity Correlate with Postoperative Complications After Elective Posterior Cervical Spine Fusion? World neurosurgery 2020;141:e231-e8.\u003c/li\u003e\n\u003cli\u003ePorche K, Lockney DT, Gooldy T, Kubilis P, Murad G. Nuchal thickness and increased risk of surgical site infection in posterior cervical operations. Clinical neurology and neurosurgery 2021;205:106653.\u003c/li\u003e\n\u003cli\u003eSridharan M, Malik AT, Kim J, Khan SN, Yu E. Does Increasing Body Mass Index Correlate with Adverse Outcomes Following Posterior Cervical Fusions? World neurosurgery 2020;133:e789-e95.\u003c/li\u003e\n\u003cli\u003eWang J, Chang Y, Suo M, Huang H, Liu X, Li Z. Incidence and risk factors of surgical site infection following cervical laminoplasty: A retrospective clinical study. Int Wound J 2023;21(2).\u003c/li\u003e\n\u003cli\u003eLee JJ, Odeh KI, Holcombe SA, Patel RD, Wang SC, Goulet JA, et al. Fat Thickness as a Risk Factor for Infection in Lumbar Spine Surgery. Orthopedics 2016;39(6):e1124-e8.\u003c/li\u003e\n\u003cli\u003eSang C, Chen X, Ren H, Meng Z, Jiang J, Qin Y. Correlation between lumbar multifidus fat infiltration and lumbar postoperative infection: a retrospective case-control study. BMC Surg 2020;20(1):35.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTables 1 to 3 are available in the Supplementary Files section.\u003c/p\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":"SSI, Posterior cervical decompression, Postoperative complications, Cervical spine","lastPublishedDoi":"10.21203/rs.3.rs-6572326/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6572326/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eLocal subcutaneous fat thickness has been identified as a significant predictor for the risk of surgical site infection (SSI) in lumbar spine procedures. Emerging research suggests its potential relevance in posterior cervical spine surgery as well. This study aims to further explore the connection, focusing on the comparative impact of Body Mass Index (BMI) and localized fat thickness at the C5 level on the risk of SSIs.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eThis study presents a comprehensive retrospective analysis of patients treated with posterior cervical decompression without fusion for mono- or multisegmental cervical spondylotic myelopathy. From 2015 to 2022. Exclusions were made for minors and individuals who received posterior cervical instrumentation. Measurements of localized nuchal and fat thickness at the C5 level were taken. Patient charts provided data on demographics, BMI, diabetic status, smoking history, previous surgical history, the extent of surgery (number of operated levels), and duration of hospital stay. A combination of univariate and multivariate analysis was employed to identify significant predictors of SSIs.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003e\u0026nbsp;From the 346 patients who qualified for the study, 20 (5.8%) experienced SSIs. Those with SSIs generally had higher BMIs (median 29 vs. 27, p=0.032), greater nuchal fat thickness (median 27mm vs. 23mm, p=0.012), and more extensive surgeries (75% had multiple levels operated compared to 55% in the non-SSI cohort, p=0.001). Additionally, the occurrence of SSI resulted in a prolonged hospital stay (median 12 days vs. 7 days, p≤0.001). However, in multivariate logistic regression, nuchal fat thickness was not a significant predictor, whereas BMI and the number of operated levels were confirmed as substantial predictors of SSI (OR=1.095, CI: 1.005 to 1.192, p= 0.038 and OR=2.089, CI: 1.3 to 3.357, p= 0.002 respectively).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003e\u0026nbsp;This research indicates that contrary to initial assumptions, localized fat thickness at the C5 level is not a significant predictive factor for SSI post posterior cervical decompression. Instead, it underscores the importance of BMI and the extent of surgical intervention as considerable, quantifiable risk factors for SSIs. These findings can guide more effective preoperative assessments and targeted interventions to mitigate SSI risks in posterior cervical decompression surgeries.\u003c/p\u003e","manuscriptTitle":"Assessing Surgical Site Infection Risks in Posterior Cervical Decompression: The Role of Local Fat Thickness","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-04 13:07:30","doi":"10.21203/rs.3.rs-6572326/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":"b254d950-bc43-4785-85ff-cdcb0cb9a0d3","owner":[],"postedDate":"June 4th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-07-05T12:38:21+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-04 13:07:30","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6572326","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6572326","identity":"rs-6572326","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}