Body Mass Index as A risk Factor for Recurrence and Frequency of Re-surgery After Lumber Spine Surgery

Body Mass Index as A risk Factor for Recurrence and Frequency of Re-surgery After Lumber Spine Surgery | 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 Body Mass Index as A risk Factor for Recurrence and Frequency of Re-surgery After Lumber Spine Surgery Mohammad Abdulsalam Soliman, Eslam Abozeid Kandil, Ahmed Ibrahim Salama, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8167610/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: Obesity is a well-established risk factor for numerous health complications, yet its impact on postoperative recurrence and the need for re-surgery after lumbar spine surgery remains unclear. Lumbar spine surgery is a common treatment for degenerative spinal disorders; however, recurrence of symptoms and subsequent re-surgery continue to pose significant postoperative challenges. Body mass index (BMI) has been suggested as a potential risk factor affecting surgical outcomes due to its biomechanical and metabolic effects. This study aimed to evaluate the association between BMI and the risk of recurrence and re-surgery following lumbar spine surgery. Objective: To evaluate the association between BMI and the risk of recurrence and re-surgery after lumbar spine surgery. Methods: This is a retrospective cohort study that included adult patients who underwent a single stable lumbar spine discectomy for degenerative disc disease at Al-Ahrar Teaching Hospital and Zagazig University Hospitals, Zagazig, Egypt, between January 2015 and October 2025. Patients with multilevel disc pathology, concomitant cervical or thoracic spine disorders, unstable vertebrae, or a history of previous lumbar surgery were excluded. BMI was recorded at the time of the first surgery and at the follow-up. Results: The study included 286 patients (171 males and 115 females); we selected 286 cases from the hospital medical records, among more than 5,000 cases operated on during 10 years, with a mean age of 41.9 ± 11.2 years. Recurrence of lumbar surgery occurred in 28 patients (9.8%). Higher BMI was significantly associated with recurrence: 18 (64.3%) of overweight/ obese patients and required re-surgery, compared with 10 (35.7%) of patients with a healthy weight. The mean BMI at the time of the initial surgery was significantly higher in the recurrence group (25.8 ± 2.8 kg/m²) than in the non-recurrence group (22.9 ± 2.0 kg/m²; p < 0.001). Similarly, BMI at follow-up remained greater among patients with recurrence (25.0 ± 2.6 vs. 21.9 ± 2.1 kg/m²; p < 0.001). Obesity-related comorbidities were present in (66.7%) of patients, with type 2 diabetes (24.1%) and cardiovascular disease (18.3%) being the most common. Conclusion: Higher BMI is significantly associated with recurrence and need for re-surgery following lumbar spine surgery, identifying elevated BMI as an independent risk factor. BMI should be considered during preoperative risk assessment and postoperative counseling. Implementing weight optimization strategies before and after surgery may improve long-term outcomes and reduce recurrence rates. Body Mass Index Lumbar Spine Surgery Recurrence Re-surgery Risk Factor Figures Figure 1 Figure 2 Figure 3 Introduction Overweight and obesity are physical conditions characterized by an excessive accumulation of body fat. They are commonly defined according to body mass index (BMI), where overweight is a BMI between 25 and 29.9 kg/m², while obesity corresponds to a BMI ≥ 30 kg/m². ( 1 ) It remains a widely used and reliable surrogate indicator of obesity and overweight due to its strong correlation with direct measures of adiposity. ( 2 ) The prevalence of obesity and overweight has reached epidemic proportions worldwide. According to the World Health Organization (WHO), approximately 11% of the global adult population was obese, and 35% were overweight. ( 3 ) In many countries, individuals classified as obese or overweight constitute the majority of the population. Indeed, in over half of the member countries of the Organization for Economic Co-operation and Development (OECD), at least one in two adults is either overweight or obese. ( 4 ) Lumbar spine surgery is commonly performed to treat degenerative spinal conditions such as herniated intervertebral discs and lumbar spinal stenosis. ( 5 ) Despite continuous advancements in surgical techniques, postoperative recurrence and the need for revision surgery remain major clinical challenges, influencing both patient satisfaction and healthcare costs. Compared with conservative treatment, surgical intervention often provides more rapid and significant relief of pain and neurological symptoms. However, complications such as recurrent lumbar disc herniation (R-LDH) still occur, with recurrence rates reported between 5% and 18%. ( 6 , 7 ) Secondary operations are technically more demanding due to epidural scarring and are associated with increased physical and psychological distress for patients as well as higher societal costs. ( 5 , 8 ) Numerous studies have investigated potential risk factors for R-LDH, including age, sex, BMI, smoking status, diabetes, herniation type, and spinal level. ( 9 , 10 , 11 , 12 ) However, the findings across these studies remain inconsistent. Among these factors, BMI has been proposed as an important determinant of surgical outcome. Elevated BMI may increase mechanical stress on the lumbar spine, alter postoperative healing, and contribute to early symptom recurrence. ( 10 – 11 ) Nonetheless, the literature remains inconclusive regarding the strength and direction of this association. In recent years, increasing attention has been given to the biomechanical implications of excessive body weight on spinal health. ( 13 ) Excess body mass acts as an additional load during physical activity, potentially elevating lumbar biomechanical stress and contributing to low back pain (LBP) and postoperative recurrence. Given these considerations, further investigation into the role of BMI as a risk factor for recurrence and the frequency of re-surgery after lumbar spine surgery is warranted. Patients and methods This retrospective cohort study included all adult patients (aged ≥ 18 years) who underwent stable single-level lumbar spine discectomy for degenerative disc disease at Al-Ahrar Teaching Hospital and Zagazig University Hospitals, Zagazig, Egypt, between January 2015 and October 2025. It was conducted with ethical approval obtained from Research Review Board of General Organization of Teaching Hospitals and Institutes (GOTHI, approval number HAH00034). We conducted a retrospective review of hospital medical records about 10 years. During that time, 5,110 patients underwent different spinal surgeries due to degenerative disease. From these, we selected only the cases with a single stable lumbar disc herniation, excluding those with additional conditions such as multilevel pathology or those that needed fusion surgery or any history of previous spinal surgery. This resulted in 654 eligible cases. Among these, 286 patients had adequate follow-up for at least five years, including postoperative MRI evaluation. Out of these, 28 patients showed evidence of recurrence, which needed redo surgery. All patients underwent preoperative and follow-up lumbar spine radiographs, including dynamic views, as well as magnetic resonance imaging (MRI). We routinely record the body weight of every patient in the outpatient department, and we calculate the BMI at the time of surgery and during follow-up. According to the literature, approximately 50% of lumbar disc herniation recurrences occur within the first year after surgery. ( 14 , 15 , 16 ) Therefore, in this study, each patient was followed for up to five years after surgery to assess the incidence of recurrence and the need for reoperation. Statistical Analysis Continuous variables were expressed as mean ± standard deviation (SD), and categorical variables were summarized as frequencies and percentages. The independent t-test was used to compare BMI values between the recurrence and non-recurrence groups. The chi-square test was used to evaluate the association between sex, infection postoperatively, and recurrence. Binary logistic regression analysis was performed to determine the effect of BMI on recurrence after adjusting for age and sex. A p-value < 0.05 was considered statistically significant. Statistical analyses were conducted using SPSS version 28.0 (IBM Corp., Armonk, NY, USA). Results The study included 286 patients, 171 (59.8%) males and 115 (40.2%) females, with a mean age of 41.9 ± 11.2 years. A high BMI included; overweight/obese patients (≥ 25.0 kg/m 2 ) represented 87 individuals (30.4%) of the total cohort. Recurrence occurred in 28 patients (9.8%). We found a mean BMI at the time of first operation was 23.6 ± 2.5 kg/m², and at follow-up it was 22.7 ± 2.3 kg/m² Among the 87 patients with obesity, 58 (66.7%) had one or more obesity-related comorbidities. Endocrine disorders, specifically type 2 diabetes mellitus, were present in 21 patients (24.1 %). Cardiovascular conditions, including hypertension, stroke, and myocardial infarction, were observed in 16 patients (18.3%). Musculoskeletal complications, such as osteoarthritis, affected 8 patients (9.2%), while gastrointestinal issues, including gallbladder disease and non-alcoholic fatty liver disease, were noted in 3 patients (3.4%). Respiratory comorbidities, specifically sleep apnea, and mental health disorders, such as depression, were each observed in 2 patient (2.3%). In this cohort, the most frequently operated disc levels were L4/L5 (42.3%) and L5/S1 (40.2%), together accounting for more than 80% of all cases. Recurrence was similarly concentrated at these levels, with 11 cases (39.3%) at L4/L5 and 12 cases (42.9%) at L5/S1. The distribution of recurrence across the five disc levels closely mirrored their overall frequencies in the cohort. A chi-square test demonstrated no significant association between disc level and postoperative recurrence (chi-square = 0.55, p = 0.968), indicating that recurrence occurred proportionally across disc levels without any specific level being more prone to re-herniation. Table 1 Microscopic discectomy was the predominant surgical technique, performed in 209 patients (73.1%) and included procedures such as laminectomy, hemi-laminectomy, or fenestration, while endoscopic discectomy was performed in 77 patients (26.9%). Recurrence occurred in 17 patients (60.7%) following microscopic discectomy and in 11 patients (39.3%) after endoscopic procedures. Although recurrence appeared slightly more frequent in the endoscopic group relative to its proportion of total cases, this difference was not statistically significant (chi-square = 2.41, p = 0.121). Overall, recurrence rates were distributed proportionally between the two techniques, indicating that the choice of surgical approach did not have a significant impact on postoperative recurrence. Table 1 In our study, postoperative wound infection occurred in 19 of the 286 patients included (6.6%). The infection rate was higher among overweight and obese patients (10 of 87; 11.5%) compared with patients with normal BMI (9 of 199; 4.5%). Although the infection rate in overweight/obese patients was more than twice that of patients with normal BMI, this difference was statistically significant (chi-square χ² = 4.75, p = 0.029). Regarding recurrence, postoperative infection was observed in 5 patients with recurrence and 14 patients without recurrence. This difference was also statistically significant (two-tailed Fisher’s exact test, p = 0.015), indicating that postoperative wound infection was associated with a higher risk of recurrence following lumbar discectomy. Table 1. The odds of postoperative infection were approximately 3.8 times higher in the recurrent group . Table 3 Table 1. Comparison of demographic and clinical characteristics between patients with and without recurrence after lumbar spine surgery Variable Overall (n=286) Recurrence (n=28) No Recurrence (n=258) p-value Age (years) (mean±SD) 41.9 ± 11.2 42.7 ± 11.6 41.6 ± 11.1 0.63 Sex (M/F) (frequency) 171/115 17/11 154/104 0.91 LDH Level: n (%) L1/L2 L2/L3 L3/L4 L4/L5 L5/S1 7 (2.4%) 16 (5.6%) 27 (9.4%) 121 (42.3%) 115 (40.2%) 1 (3.6%) 2 (7.1%) 2 (7.1%) 11 (39.3%) 12 (42.9%) 6 (2.3%) 14 (5.4%) 25 (9.7%) 110 (42.6%) 103 (39.9%) 0.968 Surgical techniques: n (%) Microscopic discectomy Endoscopic discectomy 209 (73.1%) 77 (26.9%) 17 (60.7%) 11 (39.3%) 192 (74.4%) 66 (25.6%) 0.121 Postoperative infection 19 (6.6%) 5 (17.6%) 14 (5.4%) 0.015 BMI at first surgery (kg/m²) (mean±SD) 23.6 ± 2.5 25.8 ± 2.8 22.9 ± 2.0 0.001 BMI at follow-up (kg/m²) (mean±SD) 22.7 ± 2.3 25 ± 2.6 21.9 ± 2.1 0.001 Patients with recurrence had a significantly higher BMI at the time of the first surgery compared to those without recurrence (25.8 ± 2.8 kg/m² vs. 22.9 ± 2.0kg/m², p = 0.001). Similarly, BMI at follow-up was also significantly higher in the recurrence group (25 ± 2.6 kg/m² vs. 21.9 ± 2.1kg/m², p = 0.001). No significant differences were observed between the two groups regarding age (p = 0.63) or sex (p = 0.91). Table 3 Kaplan–Meier survival analysis demonstrated a clear difference in recurrence-free survival between the two BMI categories over the 5-year follow-up period. Patients with normal BMI (<25.0 kg/m²) exhibited a substantially longer recurrence-free survival, with a median of approximately 4.9 years, compared to only 2.2 years among those with high BMI (≥25.0 kg/m²). The survival curves diverged early and continued to separate throughout the follow-up, indicating a persistent increased risk of recurrence in the higher BMI group. Censoring occurred at 5 years for patients who remained recurrence-free. The difference between the two groups was statistically significant according to the log-rank test (χ² = 28.9, p < 0.001), confirming that elevated BMI is associated with a markedly reduced recurrence-free survival following lumbar spine surgery. Figure 1 Table 2. Distribution of BMI categories among patients with and without recurrent lumbar surgery BMI Classification n (%) Recurrent lumber surgery 28 (9.8%) Non recurrence 258 (90.2%) Total 286 (100%) Normal BMI ( < 25.0 kg/m 2 ): 10 (35.7%) 189 (73.3%) 199 (69.6%) (< 18.5 kg/m 2 ) Underweight 0 (0%) 1 (0.4%) 1 (0.3%) (18.5–24.9 kg/m 2 ) Healthy Weight 10 (35.7%) 188 (72.9%) 198 (69.2%) High BMI (≥ 25.0 kg/m 2 ): 18 (64.3%) 69 (26.7%) 87 (30.4%) (25.0–29.9 kg/m2) Overweight 13 (46.4%) 60 (23.3%) 81 (28.3%) (≥ 30.0 kg/m2) Obese 5 (17.9%) 1 (0.4%) 6 (2.1%) Healthy-weight patients (BMI 18.5–24.9 kg/m²) predominated among those without recurrence, accounting for 188 patients (72.9%), whereas this category was considerably less common among patients with recurrence, observed in only 10 cases (35.7%). In contrast, patients with a high BMI (≥ 25.0 kg/m²) - including both the overweight (25.0–29.9 kg/m²) and obese (≥ 30.0 kg/m²) categories - were much more frequent among those with recurrence, comprising 28 patients (64.3%) in total. The mean follow-up time was 48.1 ± 11.3 months (range, 12–60 months), with follow-up extending up to 5 years. Table 2 There was a highly significant association between BMI category and recurrence following lumbar spine surgery (p < 0.001). Patients with elevated BMI (overweight or obese) were disproportionately represented in the recurrence group compared with the non-recurrence group (64.3% vs 26.7%), indicating that higher BMI is strongly associated with an increased risk of postoperative recurrence (Chi-square test: χ² = 16.84, df = 1, p < 0.001). Moreover, each 1 kg/m² increase in BMI at the time of surgery was associated with 38% higher odds of recurrence (OR = 1.38 per 1 kg/m² increase, 95% CI 1.17–1.63, p < 0.001). Table 2 Binary logistic regression was performed to identify independent predictors of recurrence following lumbar spine surgery. The analysis revealed that postoperative wound infection and higher BMI at the time of the first surgery were significant independent predictors. Patients who developed a postoperative infection had higher odds of recurrence compared with those without infection, and each 1 kg/m² increase in BMI was associated with increased odds of recurrence. In contrast, age, sex, level of disc herniation, and surgical technique were not significantly associated with recurrence. These findings indicate that elevated BMI and postoperative wound infection are independent risk factors for recurrence, even after adjusting for potential demographic and clinical confounders. Table3 Table 3. Binary Logistic Regression Analysis of Risk Factors for Recurrence after Lumbar Spine Surgery Variable OR 95% CI p-value BMI (per 1 kg/m² increase) 1.38 1.17–1.63 0.001* Postoperative infection 3.77 1.25–11.42 0.019* Age (years) 1.01 0.97–1.05 0.63 Sex (Male) 1.03 0.50–2.12 0.91 LDH level (categorical) – – 0.968 Surgical technique (Endoscopic) 1.89 0.88–4.05 0.121 * Statistically significant In this study of 286 patients undergoing lumbar spine surgery, BMI ranged from approximately 18.4 to 41.1 kg/m², reflecting a predominantly healthy to overweight population. Using ROC analysis, an optimal BMI cut-off of 25.0 kg/m² was identified to predict postoperative recurrence. At this threshold, the sensitivity was 64.3%, indicating that a high proportion of patients who eventually experienced recurrence had a BMI ≥ 25.0 kg/m². The specificity was 73.2%, showing that most patients without recurrence had a BMI below this threshold. The Youden’s Index of 0.375 demonstrates a good balance between sensitivity and specificity, and the AUC of 0.75 indicates that BMI is moderately strong discriminator for predicting recurrence after lumbar spine surgery. Overall, these findings suggest that even modest increases in BMI above the healthy weight range may significantly elevate the risk of recurrence, supporting the importance of preoperative BMI assessment and potential weight optimization strategies for improving surgical outcomes. Illustrative Case: A 34-year-old male presented during a 26-month follow-up with low back pain (LBP) and left-sided sciatica. His BMI was 28.3. He had a history of prior lumbar surgery—L5–S1 discectomy via left hemilaminectomy. Initial lumbosacral spine MRI had revealed a left-sided L5–S1 disc herniation. (Figure 2) Neurological examination demonstrated motor weakness in the left lower limb, with ankle plantarflexion graded 4/5 and partial left foot drop graded 3/5. Sensory deficits were present along the L5–S1 dermatome, and deep tendon reflexes were diminished at the left ankle. Follow-up lumbosacral MRI revealed recurrent disc herniation at the same level (L5–S1). (Figure 3) Discussion Obesity is widely recognized as an important contributor to the development and progression of degenerative spinal pathology. Numerous studies have demonstrated a higher prevalence of degenerative disc disease among obese individuals compared with those of normal weight. ( 17 , 18 ) Similarly, a linear correlation between BMI and the severity of degenerative changes supports a dose-dependent relationship between excess body weight and disc degeneration. ( 19 ) Clinically, these structural alterations manifest as increased rates of low back pain, radiculopathy, and disability. Meta-analyses have shown that obese individuals are more likely to experience chronic low back pain and seek medical intervention for spinal symptoms. ( 20 ) The mechanisms underlying this relationship are multifactorial, involving both biomechanical and metabolic pathways. From a biomechanical perspective, excess body weight increases axial loading on the lumbar spine, resulting in greater compressive stress on intervertebral discs, facet joints, and supporting ligaments. This stress may contribute to disc bulging, infolding of the ligamentum flavum, and reduced space for neural elements ( 21 ) . Obesity is also frequently associated with fatty infiltration and atrophy of paraspinal muscles, particularly the multifidus, which compromises spinal stability and accelerates degenerative changes ( 22 ) . Furthermore, the additional mechanical load from excess body mass during movement and lifting activities elevates compressive and shear forces on the spinal column, potentially accelerating disc degeneration and predisposing individuals to recurrent herniation. ( 23 ) The obesity-related increase in lumbar spine loading is believed to arise primarily from excess body mass acting as an additional mechanical load during movement and lifting activities. This added load elevates the compressive and shear forces on the spinal column. Although severely obese individuals may adopt different lifting postures or movement strategies to compensate for their body mass, investigating such biomechanical adaptations was beyond the scope of the present study. Beyond mechanical stress, obesity induces metabolic and inflammatory effects that further contribute to spinal degeneration. Adipose tissue secretes proinflammatory adipokines such as leptin, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 (IL-1), which promote chronic low-grade inflammation and extracellular matrix breakdown within intervertebral discs ( 21 , 22 , 24 ) . Elevated C-reactive protein levels and increased matrix metalloproteinase (MMP) activity observed in obese patients support this inflammatory hypothesis. Moreover, vascular compromise associated with atherosclerosis and impaired endplate diffusion may reduce nutrient delivery to disc cells, accelerating disc desiccation and degeneration. ( 21 , 22 , 24 ) Although the overall incidence of postoperative wound infection was relatively low (6.6%), overweight/obese patients experienced a higher infection rate (11.5%) compared with patients with normal BMI (4.5%). This difference was statistically significant (Chi-square = 4.75, p = 0.029), and is consistent with previous literature indicating that obesity contributes to impaired wound healing and an increased susceptibility to surgical complications. ( 24 – 26 ) Collectively, these biomechanical and biochemical alterations explain why patients with higher BMI not only develop degenerative changes earlier but may also experience higher rates of postoperative recurrence. Our study findings are consistent with this evidence, demonstrating that increased BMI is an independent predictor of recurrence and re-surgery after lumbar spine discectomy. The combination of increased mechanical loading, muscle dysfunction, and chronic inflammation likely compromises healing and accelerates further degenerative processes following surgery. In this study, each patient was followed for up to five years after surgery to assess the incidence of recurrence and the need for reoperation. The timing of R-LDH varies across studies. Shepard and Cho ( 14 ) reported that approximately half of all recurrences occur within the first year following surgery, though late recurrences have been documented up to 8–10 years postoperatively. Similarly, Hlubek and Mundis ( 15 ) noted that the majority of recurrences develop within 6–18 months after the initial discectomy, emphasizing the early postoperative period as a critical window for recurrence risk. The results of this study demonstrate a significant association between higher BMI and an increased risk of recurrence or the need for re-surgery following lumbar spine surgery. Patients with elevated BMI at the time of their initial operation were more likely to experience recurrent symptoms and to require additional surgical intervention. Our findings are consistent with previous reports identifying obesity as a significant risk factor for postoperative complications and poorer outcomes after spinal procedures. Excess body weight increases intradiscal pressure and spinal instability, which may promote recurrent herniation. In addition to these mechanical effects, obesity is associated with systemic metabolic alterations—such as chronic low-grade inflammation, impaired microvascular perfusion, and delayed tissue healing—that may compromise recovery and structural repair following surgery. Previous studies examining BMI as a predictor of R-LDH have yielded mixed results. Several investigations compared BMI between recurrent and non-recurrent groups ( 7 , 9 , 10 , 12 , 14 – 16 , 27 – 29 ) . For example, studies evaluating BMI > 25 kg/m² found it to be significantly associated with recurrence, with an odds ratio comparable to our result (OR = 1.38; 95% CI, 1.17–1.63; P < 0.001) ( 26 ) . Similarly, another study reported significantly higher BMI among patients who developed recurrence ( 29 ) , whereas one study did not find a significant association ( 27 ) . Our findings, demonstrating that higher BMI independently predicts recurrence, support the subset of studies suggesting that excessive body weight contributes to poorer surgical outcomes. These results align with biomechanical evidence indicating that obesity increases axial loading on the lumbar spine, elevates compressive and shear forces on intervertebral discs, and impairs paraspinal muscle function, potentially accelerating disc degeneration and predisposing patients to recurrence ( 21 , 22 ) . Our results underscore the importance of weight optimization as a modifiable risk factor in patients undergoing lumbar spine procedures. Preoperative counseling and postoperative lifestyle interventions aimed at reducing BMI could play a critical role in improving long-term surgical outcomes and minimizing recurrence rates. Conclusion Higher body mass index (BMI) is significantly associated with recurrence and the need for re-surgery following lumbar discectomy, highlighting excess body weight as a modifiable risk factor. Patients with elevated BMI at the time of their initial operation were more likely to experience postoperative recurrence, emphasizing the importance of incorporating BMI into preoperative risk stratification and postoperative counseling. These findings suggest that preoperative weight optimization and postoperative lifestyle management may improve surgical outcomes and reduce recurrence rates. Limitations Despite these findings, several limitations should be acknowledged. The retrospective design limits causal inference and may introduce selection bias. Potential confounding factors—such as comorbidities, variations in surgical technique, adherence to postoperative rehabilitation, and lifestyle factors—were not controlled in this analysis. Further prospective, multicenter studies are needed to validate these results and to clarify the biomechanical and metabolic mechanisms through which obesity affects spinal pathology and surgical outcomes. Future research should also consider preoperative BMI optimization programs and long-term follow-up to evaluate the impact of BMI changes on the risk of re-surgery. Abbreviations BMI = Body Mass Index, MRI: Magnetic Resonance Imaging, LDH= Lumbar Disc Herniation, R-LDH= Recurrent-Lumbar Disc Herniation, TNF-α = Tumor Necrosis Factor-alpha, IL-6 = Interleukin-6, IL-1= Interleukin-1, MMP = Matrix Metalloproteinase, WHO =World Health Organization, OECD = the Organization for Economic Co-operation and Development, GOTHI = The General Organization of teaching hospitals and institutes in Egypt. Declarations Ethics approval and consent to participate Ethical approval was obtained from the Ethical and Research Committee in General Organization of teaching hospitals and institutes, Egypt (GOTHI, approval number HAH00034). Consent for publication Consent to publish obtained from patients to publish their data and imaging. Availability of data and materials All data generated or analysed during this study are included in this published article in the results section. Competing Interests The authors declare that they have no competing interests Funding The authors received no specific funding from any public, commercial, or not-for-profit organization for the conduct of this research. References Lean, M. (2023). Overweight and obesity. Essentials of Human Nutrition 6e , 287. Karchynskaya, V., Kopcakova, J., Klein, D., Gába, A., Madarasova-Geckova, A., van Dijk, J. P., ... & Reijneveld, S. A. (2020). Is BMI a valid indicator of overweight and obesity for adolescents?. 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Risk factors of recurrent lumbar disk herniation. Asian journal of neurosurgery, 8(02), 93-96. Miwa, S., Yokogawa, A., Kobayashi, T., Nishimura, T., Igarashi, K., Inatani, H., & Tsuchiya, H. (2015). Risk factors of recurrent lumbar disk herniation: a single center study and review of the literature. Clinical Spine Surgery , 28 (5), E265-E269. Yao, Y., Liu, H., Zhang, H., Wang, H., Zhang, C., Zhang, Z., ... & Zhou, Y. (2017). Risk factors for recurrent herniation after percutaneous endoscopic lumbar discectomy. World neurosurgery , 100 , 1-6 Additional Declarations No competing interests reported. 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. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8167610","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":548751363,"identity":"b56b9fd4-bed7-4559-891e-987b72715373","order_by":0,"name":"Mohammad Abdulsalam Soliman","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABC0lEQVRIie3PMUvDQBTA8RcCnc44l5OcX0C4EOiS0s/SI9AsOelUMp5U4tg1fotM4ng1g8uZrpE4tItTh6BjF89uQkLsJnj/5Th4P94dgMn0F5MANgzgQh8CIBm7AOh3RI9ZmqiZfyKxbp+Y6CNOLa3P+aJA5G598/EqZJQ/v6y3DUzcK9FOhuXUxllZIKrYEvPHN56r69DLIPRHsp1QBYDPUk2ACczVO89lPMIIJHvoJvbhm5DVbnngaRHRzb6XDI5boGIp1mRKq54tQ02CrIwQrXZpEKuZd1/tfS+j3X9x9MPq+SJwySos6jgZE2cTe9smmbhdBOC8+Xm/PE7SrvG2iDhl2mQymf5DX9F8YziWosDCAAAAAElFTkSuQmCC","orcid":"","institution":"Alahrar Teaching Hospital","correspondingAuthor":true,"prefix":"","firstName":"Mohammad","middleName":"Abdulsalam","lastName":"Soliman","suffix":""},{"id":548751364,"identity":"a43e6ade-6829-4ac4-ba92-4002ad61da94","order_by":1,"name":"Eslam Abozeid Kandil","email":"","orcid":"","institution":"Alahrar Teaching 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14:09:33","extension":"xml","order_by":9,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":86049,"visible":true,"origin":"","legend":"","description":"","filename":"4cb14ba1b61e42ea96f5f1d3a7a535a01structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-8167610/v1/1143286d26575ecbcb327057.xml"},{"id":96805724,"identity":"a2b27038-7182-4f3a-9471-e8fc168f6e05","added_by":"auto","created_at":"2025-11-26 09:11:27","extension":"html","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":96728,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-8167610/v1/315048a69a1022b74cc0031f.html"},{"id":96805711,"identity":"990f370e-80e9-4783-adf8-5118be0ab24c","added_by":"auto","created_at":"2025-11-26 09:11:26","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":65496,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eKaplan–Meier curves for recurrence-free survival according to BMI category.\u003c/strong\u003e\u003cbr\u003e\nPatients with high BMI (≥25.0 kg/m²) demonstrated significantly lower recurrence-free survival compared with those with normal BMI (\u0026lt;25.0 kg/m²) over the 5-year follow-up period (log-rank test: χ² = 28.9, \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.001). The estimated 5-year recurrence-free survival rates were 87.5% in the normal BMI group and 43.2% in the high BMI group.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8167610/v1/833dab96d3b4c723be9816b7.png"},{"id":96917320,"identity":"04f692a9-374d-4607-9465-72b555ad8028","added_by":"auto","created_at":"2025-11-27 14:09:32","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":778952,"visible":true,"origin":"","legend":"\u003cp\u003eInitial lumbosacral spine MRI demonstrated loss of normal disc height and increased signal intensity associated with a left-sided L5–S1 disc herniation, which had previously been present at the time of the first surgery.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8167610/v1/52ceee22bb26d13e55fd5cc0.png"},{"id":96805717,"identity":"ee5e72b8-d919-4c4b-b6c8-1f1cdeade20a","added_by":"auto","created_at":"2025-11-26 09:11:27","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":831668,"visible":true,"origin":"","legend":"\u003cp\u003eAfter a 26-month follow-up, lumbosacral spine MRI revealed a recurrent disc herniation at the same level (L5–S1). A large left paracentral/posterolateral disc extrusion at the L5–S1 level was noted, indenting the left ventral aspect of the thecal sac and anterior epidural fat, and causing severe compression of the left traversing nerve root and left exit canal.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-8167610/v1/d390d6f5df79cbfe08fbf9bc.png"},{"id":96922618,"identity":"75e2bb55-4886-4eb8-8a4c-e2118ff695ab","added_by":"auto","created_at":"2025-11-27 14:19:35","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3017127,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8167610/v1/749f14df-23c7-423c-83af-831687486cc6.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Body Mass Index as A risk Factor for Recurrence and Frequency of Re-surgery After Lumber Spine Surgery","fulltext":[{"header":"Introduction","content":"\u003cp\u003eOverweight and obesity are physical conditions characterized by an excessive accumulation of body fat. They are commonly defined according to body mass index (BMI), where overweight is a BMI between 25 and 29.9 kg/m\u0026sup2;, while obesity corresponds to a BMI\u0026thinsp;\u0026ge;\u0026thinsp;30 kg/m\u0026sup2;. \u003csup\u003e(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e)\u003c/sup\u003e It remains a widely used and reliable surrogate indicator of obesity and overweight due to its strong correlation with direct measures of adiposity. \u003csup\u003e(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eThe prevalence of obesity and overweight has reached epidemic proportions worldwide. According to the World Health Organization (WHO), approximately 11% of the global adult population was obese, and 35% were overweight. \u003csup\u003e(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/sup\u003e In many countries, individuals classified as obese or overweight constitute the majority of the population. Indeed, in over half of the member countries of the Organization for Economic Co-operation and Development (OECD), at least one in two adults is either overweight or obese. \u003csup\u003e(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e)\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eLumbar spine surgery is commonly performed to treat degenerative spinal conditions such as herniated intervertebral discs and lumbar spinal stenosis. \u003csup\u003e(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/sup\u003e Despite continuous advancements in surgical techniques, postoperative recurrence and the need for revision surgery remain major clinical challenges, influencing both patient satisfaction and healthcare costs. Compared with conservative treatment, surgical intervention often provides more rapid and significant relief of pain and neurological symptoms. However, complications such as recurrent lumbar disc herniation (R-LDH) still occur, with recurrence rates reported between 5% and 18%. \u003csup\u003e(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e)\u003c/sup\u003e Secondary operations are technically more demanding due to epidural scarring and are associated with increased physical and psychological distress for patients as well as higher societal costs. \u003csup\u003e(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e)\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eNumerous studies have investigated potential risk factors for R-LDH, including age, sex, BMI, smoking status, diabetes, herniation type, and spinal level. \u003csup\u003e(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e)\u003c/sup\u003e However, the findings across these studies remain inconsistent. Among these factors, BMI has been proposed as an important determinant of surgical outcome. Elevated BMI may increase mechanical stress on the lumbar spine, alter postoperative healing, and contribute to early symptom recurrence. \u003csup\u003e(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/sup\u003e Nonetheless, the literature remains inconclusive regarding the strength and direction of this association.\u003c/p\u003e\u003cp\u003eIn recent years, increasing attention has been given to the biomechanical implications of excessive body weight on spinal health. \u003csup\u003e(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e)\u003c/sup\u003e Excess body mass acts as an additional load during physical activity, potentially elevating lumbar biomechanical stress and contributing to low back pain (LBP) and postoperative recurrence. Given these considerations, further investigation into the role of BMI as a risk factor for recurrence and the frequency of re-surgery after lumbar spine surgery is warranted.\u003c/p\u003e"},{"header":"Patients and methods","content":"\u003cp\u003eThis retrospective cohort study included all adult patients (aged\u0026thinsp;\u0026ge;\u0026thinsp;18 years) who underwent stable single-level lumbar spine discectomy for degenerative disc disease at Al-Ahrar Teaching Hospital and Zagazig University Hospitals, Zagazig, Egypt, between January 2015 and October 2025. It was conducted with ethical approval obtained from Research Review Board of General Organization of Teaching Hospitals and Institutes (GOTHI, approval number HAH00034).\u003c/p\u003e\u003cp\u003e We conducted a retrospective review of hospital medical records about 10 years. During that time, 5,110 patients underwent different spinal surgeries due to degenerative disease. From these, we selected only the cases with a single stable lumbar disc herniation, excluding those with additional conditions such as multilevel pathology or those that needed fusion surgery or any history of previous spinal surgery. This resulted in 654 eligible cases. Among these, 286 patients had adequate follow-up for at least five years, including postoperative MRI evaluation. Out of these, 28 patients showed evidence of recurrence, which needed redo surgery.\u003c/p\u003e\u003cp\u003eAll patients underwent preoperative and follow-up lumbar spine radiographs, including dynamic views, as well as magnetic resonance imaging (MRI). We routinely record the body weight of every patient in the outpatient department, and we calculate the BMI at the time of surgery and during follow-up. According to the literature, approximately 50% of lumbar disc herniation recurrences occur within the first year after surgery. \u003csup\u003e(\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e)\u003c/sup\u003e Therefore, in this study, each patient was followed for up to five years after surgery to assess the incidence of recurrence and the need for reoperation.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eStatistical Analysis\u003c/strong\u003e\u003cp\u003eContinuous variables were expressed as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD), and categorical variables were summarized as frequencies and percentages. The independent t-test was used to compare BMI values between the recurrence and non-recurrence groups. The chi-square test was used to evaluate the association between sex, infection postoperatively, and recurrence. Binary logistic regression analysis was performed to determine the effect of BMI on recurrence after adjusting for age and sex. A p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant. Statistical analyses were conducted using SPSS version 28.0 (IBM Corp., Armonk, NY, USA).\u003c/p\u003e\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThe study included\u0026nbsp;286 patients, 171 (59.8%) males and 115 (40.2%)\u0026nbsp;females, with a mean age of\u0026nbsp;41.9 \u0026plusmn; 11.2 years. A high BMI included;\u0026nbsp;overweight/obese patients (\u0026ge; 25.0 kg/m\u003csup\u003e2\u003c/sup\u003e) represented 87 individuals (30.4%) of the total cohort. Recurrence occurred in 28 patients (9.8%). We found a mean BMI at the time of first operation was 23.6 \u0026plusmn; 2.5 kg/m\u0026sup2;, and at follow-up it was 22.7 \u0026plusmn; 2.3 kg/m\u0026sup2;\u003c/p\u003e\n\u003cp\u003eAmong the 87 patients with obesity, 58 (66.7%) had one or more obesity-related comorbidities. Endocrine disorders, specifically type 2 diabetes mellitus, were present in 21 patients (24.1 %). Cardiovascular conditions, including hypertension, stroke, and myocardial infarction, were observed in 16 patients (18.3%). Musculoskeletal complications, such as osteoarthritis, affected 8 patients (9.2%), while gastrointestinal issues, including gallbladder disease and non-alcoholic fatty liver disease, were noted in 3 patients (3.4%). Respiratory comorbidities, specifically sleep apnea, and mental health disorders, such as depression, were each observed in 2 patient (2.3%).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn this cohort, the most frequently operated disc levels were L4/L5 (42.3%) and L5/S1 (40.2%), together accounting for more than 80% of all cases. Recurrence was similarly concentrated at these levels, with 11 cases (39.3%) at L4/L5 and 12 cases (42.9%) at L5/S1. The distribution of recurrence across the five disc levels closely mirrored their overall frequencies in the cohort. A chi-square test demonstrated \u003cstrong\u003eno significant association\u003c/strong\u003e between disc level and postoperative recurrence (chi-square = 0.55, p = 0.968), indicating that recurrence occurred proportionally across disc levels without any specific level being more prone to re-herniation. \u003cstrong\u003eTable 1\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMicroscopic discectomy was the predominant surgical technique, performed in 209 patients (73.1%) and included procedures such as laminectomy, hemi-laminectomy, or fenestration, while endoscopic discectomy was performed in 77 patients (26.9%). Recurrence occurred in 17 patients (60.7%) following microscopic discectomy and in 11 patients (39.3%) after endoscopic procedures. Although recurrence appeared slightly more frequent in the endoscopic group relative to its proportion of total cases, this difference was not statistically significant (chi-square = 2.41, p = 0.121). Overall, recurrence rates were distributed proportionally between the two techniques, indicating that the choice of surgical approach did not have a significant impact on postoperative recurrence. \u003cstrong\u003eTable 1\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn our study, postoperative wound infection occurred in 19 of the 286 patients included (6.6%). The infection rate was higher among overweight and obese patients (10 of 87; 11.5%) compared with patients with normal BMI (9 of 199; 4.5%). Although the infection rate in overweight/obese patients was more than twice that of patients with normal BMI, this difference was statistically significant (chi-square \u0026chi;\u0026sup2; = 4.75, p = 0.029). Regarding recurrence, postoperative infection was observed in 5 patients with recurrence and 14 patients without recurrence. This difference was also statistically significant (two-tailed Fisher\u0026rsquo;s exact test, p = 0.015), indicating that postoperative wound infection was associated with a higher risk of recurrence following lumbar discectomy. \u003cstrong\u003eTable 1.\u0026nbsp;\u003c/strong\u003eThe odds of postoperative infection were \u003cem\u003eapproximately 3.8 times higher in the recurrent group\u003c/em\u003e. \u003cstrong\u003eTable 3\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1.\u003c/strong\u003e Comparison of demographic and clinical characteristics between patients with and without recurrence after lumbar spine surgery\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33.6538%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOverall\u0026nbsp;\u003c/strong\u003e\u0026nbsp; \u0026nbsp;\u003cstrong\u003e(n=286)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eRecurrence (n=28)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo Recurrence (n=258)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 8.65385%;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33.6538%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge (years)\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e(mean\u0026plusmn;SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e41.9 \u0026plusmn; 11.2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e42.7 \u0026plusmn; 11.6\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e41.6 \u0026plusmn; 11.1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 8.65385%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.63\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33.6538%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSex (M/F)\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e(frequency)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e171/115\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e17/11\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e154/104\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 8.65385%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.91\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33.6538%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLDH Level:\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003en (%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eL1/L2\u003c/p\u003e\n \u003cp\u003eL2/L3\u003c/p\u003e\n \u003cp\u003eL3/L4\u003c/p\u003e\n \u003cp\u003eL4/L5\u003c/p\u003e\n \u003cp\u003eL5/S1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e7 (2.4%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e16 (5.6%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e27 (9.4%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e121 (42.3%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e115 (40.2%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e1 (3.6%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e2 (7.1%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e2 (7.1%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e11 (39.3%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e12 (42.9%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e6 (2.3%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e14 (5.4%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e25 (9.7%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e110 (42.6%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e103 (39.9%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 8.65385%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.968\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33.6538%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSurgical techniques:\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003en (%)\u003c/strong\u003e\u003c/p\u003e\n \u003cul\u003e\n \u003cli\u003e\u003cstrong\u003eMicroscopic discectomy\u003c/strong\u003e\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eEndoscopic discectomy\u003c/strong\u003e\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e209 (73.1%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e77 (26.9%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e17 (60.7%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e11 (39.3%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e192 (74.4%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e66 (25.6%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 8.65385%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.121\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33.6538%;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperative infection\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e19 (6.6%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e5 (17.6%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e14 (5.4%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 8.65385%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.015\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33.6538%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBMI at first surgery (kg/m\u0026sup2;)\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e(mean\u0026plusmn;SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e23.6 \u0026plusmn; 2.5\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e25.8 \u0026plusmn; 2.8\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e22.9 \u0026plusmn; 2.0\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 8.65385%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33.6538%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBMI at follow-up (kg/m\u0026sup2;)\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e(mean\u0026plusmn;SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e22.7 \u0026plusmn; 2.3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e25 \u0026plusmn; 2.6\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e21.9 \u0026plusmn; 2.1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 8.65385%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003ePatients with recurrence had a significantly higher BMI at the time of the first surgery compared to those without recurrence (25.8 \u0026plusmn; 2.8 kg/m\u0026sup2; vs. 22.9 \u0026plusmn; 2.0kg/m\u0026sup2;, p = 0.001). Similarly, BMI at follow-up was also significantly higher in the recurrence group (25 \u0026plusmn; 2.6 kg/m\u0026sup2; vs. 21.9 \u0026plusmn; 2.1kg/m\u0026sup2;, p = 0.001). No significant differences were observed between the two groups regarding age (p = 0.63) or sex (p = 0.91). \u003cstrong\u003eTable 3\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eKaplan\u0026ndash;Meier survival analysis demonstrated a clear difference in recurrence-free survival between the two BMI categories over the 5-year follow-up period. Patients with normal BMI (\u0026lt;25.0 kg/m\u0026sup2;) exhibited a substantially longer recurrence-free survival, with a median of approximately 4.9 years, compared to only 2.2 years among those with high BMI (\u0026ge;25.0 kg/m\u0026sup2;). The survival curves diverged early and continued to separate throughout the follow-up, indicating a persistent increased risk of recurrence in the higher BMI group. Censoring occurred at 5 years for patients who remained recurrence-free. The difference between the two groups was statistically significant according to the log-rank test (\u0026chi;\u0026sup2; = 28.9, p \u0026lt; 0.001), confirming that elevated BMI is associated with a markedly reduced recurrence-free survival following lumbar spine surgery. \u003cstrong\u003eFigure 1\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2.\u003c/strong\u003e Distribution of BMI categories among patients with and without recurrent lumbar surgery\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42.3077%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eBMI Classification n (%)\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22.1154%;\"\u003e\n \u003cp\u003e\u003cem\u003eRecurrent lumber surgery \u003cstrong\u003e28 (9.8%)\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cem\u003eNon recurrence \u0026nbsp; \u0026nbsp;\u003cstrong\u003e258 (90.2%)\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16.3462%;\"\u003e\n \u003cp\u003e\u003cem\u003eTotal \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/em\u003e\u003cbr\u003e\u003cem\u003e\u003cstrong\u003e286 (100%)\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 42.3077%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNormal BMI (\u003c/strong\u003e\u003cem\u003e\u0026lt;\u003c/em\u003e\u003cstrong\u003e\u0026nbsp;25.0 kg/m\u003csup\u003e2\u003c/sup\u003e):\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.1154%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e10 (35.7%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e189 (73.3%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16.3462%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e199 (69.6%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 42.3077%;\"\u003e\n \u003cul\u003e\n \u003cli\u003e\u003cem\u003e(\u0026lt; 18.5\u0026nbsp;\u003c/em\u003e\u003cem\u003ekg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/em\u003e\u003cem\u003e\u0026nbsp;Underweight\u003c/em\u003e\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.1154%;\"\u003e\n \u003cp\u003e\u003cem\u003e0 (0%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cem\u003e1 (0.4%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16.3462%;\"\u003e\n \u003cp\u003e\u003cem\u003e1 (0.3%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 42.3077%;\"\u003e\n \u003cul\u003e\n \u003cli\u003e\u003cem\u003e(18.5\u0026ndash;24.9\u0026nbsp;\u003c/em\u003e\u003cem\u003ekg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/em\u003e\u003cem\u003e\u0026nbsp;Healthy Weight\u003c/em\u003e\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.1154%;\"\u003e\n \u003cp\u003e\u003cem\u003e10 (35.7%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cem\u003e188 (72.9%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16.3462%;\"\u003e\n \u003cp\u003e\u003cem\u003e198 (69.2%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 42.3077%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHigh BMI (\u0026ge; 25.0 kg/m\u003csup\u003e2\u003c/sup\u003e):\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.1154%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e18 (64.3%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e69 (26.7%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16.3462%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e87 (30.4%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 42.3077%;\"\u003e\n \u003cul\u003e\n \u003cli\u003e\u003cem\u003e(25.0\u0026ndash;29.9 kg/m2) Overweight\u003c/em\u003e\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.1154%;\"\u003e\n \u003cp\u003e\u003cem\u003e13 (46.4%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cem\u003e60 (23.3%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16.3462%;\"\u003e\n \u003cp\u003e\u003cem\u003e81 (28.3%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 42.3077%;\"\u003e\n \u003cul\u003e\n \u003cli\u003e\u003cem\u003e(\u0026ge; 30.0 kg/m2) Obese\u003c/em\u003e\u003c/li\u003e\n \u003c/ul\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22.1154%;\"\u003e\n \u003cp\u003e\u003cem\u003e5\u003cspan dir=\"RTL\"\u003e\u0026nbsp;\u003c/span\u003e(17.9%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.2308%;\"\u003e\n \u003cp\u003e\u003cem\u003e1 (0.4%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16.3462%;\"\u003e\n \u003cp\u003e\u003cem\u003e6 (2.1%)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eHealthy-weight patients (BMI 18.5\u0026ndash;24.9 kg/m\u0026sup2;) predominated among those without recurrence, accounting for 188 patients (72.9%), whereas this category was considerably less common among patients with recurrence, observed in only 10 cases (35.7%). In contrast, patients with a high BMI (\u0026ge; 25.0 kg/m\u0026sup2;) - including both the overweight (25.0\u0026ndash;29.9 kg/m\u0026sup2;) and obese (\u0026ge; 30.0 kg/m\u0026sup2;) categories - were much more frequent among those with recurrence, comprising 28 patients (64.3%) in total. The mean follow-up time was 48.1 \u0026plusmn; 11.3 months (range, 12\u0026ndash;60 months), with follow-up extending up to 5 years. \u003cstrong\u003eTable 2\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere was a highly significant association between BMI category and recurrence following lumbar spine surgery (p \u0026lt; 0.001). Patients with elevated BMI (overweight or obese) were disproportionately represented in the recurrence group compared with the non-recurrence group (64.3% vs 26.7%), indicating that higher BMI is strongly associated with an increased risk of postoperative recurrence (Chi-square test: \u0026chi;\u0026sup2; = 16.84, df = 1, p \u0026lt; 0.001). Moreover, each 1 kg/m\u0026sup2; increase in BMI at the time of surgery was associated with \u003cem\u003e38% higher\u003c/em\u003e odds of recurrence (OR =\u0026nbsp;1.38 per 1 kg/m\u0026sup2; increase, 95% CI 1.17\u0026ndash;1.63, p \u0026lt; 0.001). \u003cstrong\u003eTable 2\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBinary logistic regression was performed to identify independent predictors of recurrence following lumbar spine surgery. The analysis revealed that postoperative wound infection and higher BMI at the time of the first surgery were significant independent predictors. Patients who developed a postoperative infection had higher odds of recurrence compared with those without infection, and each 1 kg/m\u0026sup2; increase in BMI was associated with increased odds of recurrence. In contrast, age, sex, level of disc herniation, and surgical technique were not significantly associated with recurrence. These findings indicate that elevated BMI and postoperative wound infection are independent risk factors for recurrence, even after adjusting for potential demographic and clinical confounders. \u003cstrong\u003eTable3\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3. Binary Logistic Regression Analysis of Risk Factors for Recurrence after Lumbar Spine Surgery\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 55.102%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9.18367%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOR\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 20.4082%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95% CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.3061%;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 55.102%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBMI (per 1 kg/m\u0026sup2; increase)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.18367%;\"\u003e\n \u003cp\u003e1.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20.4082%;\"\u003e\n \u003cp\u003e1.17\u0026ndash;1.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.3061%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.001*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 55.102%;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperative infection\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.18367%;\"\u003e\n \u003cp\u003e3.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20.4082%;\"\u003e\n \u003cp\u003e1.25\u0026ndash;11.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.3061%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.019*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 55.102%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge (years)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.18367%;\"\u003e\n \u003cp\u003e1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20.4082%;\"\u003e\n \u003cp\u003e0.97\u0026ndash;1.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.3061%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.63\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 55.102%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSex (Male)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.18367%;\"\u003e\n \u003cp\u003e1.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20.4082%;\"\u003e\n \u003cp\u003e0.50\u0026ndash;2.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.3061%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.91\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 55.102%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLDH level (categorical)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.18367%;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20.4082%;\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.3061%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.968\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 55.102%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSurgical technique (Endoscopic)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9.18367%;\"\u003e\n \u003cp\u003e1.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20.4082%;\"\u003e\n \u003cp\u003e0.88\u0026ndash;4.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.3061%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.121\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e* Statistically significant\u003c/p\u003e\n\u003cp\u003eIn this study of 286 patients undergoing lumbar spine surgery, BMI ranged from approximately 18.4 to 41.1 kg/m\u0026sup2;, reflecting a predominantly healthy to overweight population. Using ROC analysis, an optimal BMI cut-off of 25.0 kg/m\u0026sup2; was identified to predict postoperative recurrence. At this threshold, the sensitivity was 64.3%, indicating that a high proportion of patients who eventually experienced recurrence had a BMI \u0026ge; 25.0 kg/m\u0026sup2;. The specificity was 73.2%, showing that most patients without recurrence had a BMI below this threshold. The Youden\u0026rsquo;s Index of 0.375 demonstrates a good balance between sensitivity and specificity, and the AUC of 0.75 indicates that BMI is\u0026nbsp;moderately strong discriminator for predicting recurrence after lumbar spine surgery.\u003c/p\u003e\n\u003cp\u003eOverall, these findings suggest that even modest increases in BMI above the healthy weight range may significantly elevate the risk of recurrence, supporting the importance of preoperative BMI assessment and potential weight optimization strategies for improving surgical outcomes.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eIllustrative Case:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA 34-year-old male presented during a 26-month follow-up with low back pain (LBP) and left-sided sciatica. His BMI was 28.3. He had a history of prior lumbar surgery\u0026mdash;L5\u0026ndash;S1 discectomy via left hemilaminectomy. Initial lumbosacral spine MRI had revealed a left-sided L5\u0026ndash;S1 disc herniation. \u003cstrong\u003e(Figure 2)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNeurological examination demonstrated motor weakness in the left lower limb, with ankle plantarflexion graded 4/5 and partial left foot drop graded 3/5. Sensory deficits were present along the L5\u0026ndash;S1 dermatome, and deep tendon reflexes were diminished at the left ankle. Follow-up lumbosacral MRI revealed recurrent disc herniation at the same level (L5\u0026ndash;S1). \u003cstrong\u003e(Figure 3)\u003c/strong\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eObesity is widely recognized as an important contributor to the development and progression of degenerative spinal pathology. Numerous studies have demonstrated a higher prevalence of degenerative disc disease among obese individuals compared with those of normal weight. \u003csup\u003e(\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e)\u003c/sup\u003e Similarly, a linear correlation between BMI and the severity of degenerative changes supports a dose-dependent relationship between excess body weight and disc degeneration. \u003csup\u003e(\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e)\u003c/sup\u003e Clinically, these structural alterations manifest as increased rates of low back pain, radiculopathy, and disability. Meta-analyses have shown that obese individuals are more likely to experience chronic low back pain and seek medical intervention for spinal symptoms. \u003csup\u003e(\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e)\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eThe mechanisms underlying this relationship are multifactorial, involving both biomechanical and metabolic pathways. From a biomechanical perspective, excess body weight increases axial loading on the lumbar spine, resulting in greater compressive stress on intervertebral discs, facet joints, and supporting ligaments. This stress may contribute to disc bulging, infolding of the ligamentum flavum, and reduced space for neural elements \u003csup\u003e(\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e)\u003c/sup\u003e. Obesity is also frequently associated with fatty infiltration and atrophy of paraspinal muscles, particularly the multifidus, which compromises spinal stability and accelerates degenerative changes \u003csup\u003e(\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e)\u003c/sup\u003e. Furthermore, the additional mechanical load from excess body mass during movement and lifting activities elevates compressive and shear forces on the spinal column, potentially accelerating disc degeneration and predisposing individuals to recurrent herniation. \u003csup\u003e(\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e)\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eThe obesity-related increase in lumbar spine loading is believed to arise primarily from excess body mass acting as an additional mechanical load during movement and lifting activities. This added load elevates the compressive and shear forces on the spinal column. Although severely obese individuals may adopt different lifting postures or movement strategies to compensate for their body mass, investigating such biomechanical adaptations was beyond the scope of the present study.\u003c/p\u003e\u003cp\u003eBeyond mechanical stress, obesity induces metabolic and inflammatory effects that further contribute to spinal degeneration. Adipose tissue secretes proinflammatory adipokines such as leptin, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 (IL-1), which promote chronic low-grade inflammation and extracellular matrix breakdown within intervertebral discs \u003csup\u003e(\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e)\u003c/sup\u003e. Elevated C-reactive protein levels and increased matrix metalloproteinase (MMP) activity observed in obese patients support this inflammatory hypothesis. Moreover, vascular compromise associated with atherosclerosis and impaired endplate diffusion may reduce nutrient delivery to disc cells, accelerating disc desiccation and degeneration. \u003csup\u003e(\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e)\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eAlthough the overall incidence of postoperative wound infection was relatively low (6.6%), overweight/obese patients experienced a higher infection rate (11.5%) compared with patients with normal BMI (4.5%). This difference was statistically significant (Chi-square\u0026thinsp;=\u0026thinsp;4.75, p\u0026thinsp;=\u0026thinsp;0.029), and is consistent with previous literature indicating that obesity contributes to impaired wound healing and an increased susceptibility to surgical complications. \u003csup\u003e(\u003cspan additionalcitationids=\"CR25\" citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e)\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eCollectively, these biomechanical and biochemical alterations explain why patients with higher BMI not only develop degenerative changes earlier but may also experience higher rates of postoperative recurrence. Our study findings are consistent with this evidence, demonstrating that increased BMI is an independent predictor of recurrence and re-surgery after lumbar spine discectomy. The combination of increased mechanical loading, muscle dysfunction, and chronic inflammation likely compromises healing and accelerates further degenerative processes following surgery.\u003c/p\u003e\u003cp\u003eIn this study, each patient was followed for up to five years after surgery to assess the incidence of recurrence and the need for reoperation. The timing of R-LDH varies across studies. Shepard and Cho \u003csup\u003e(\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e)\u003c/sup\u003e reported that approximately half of all recurrences occur within the first year following surgery, though late recurrences have been documented up to 8\u0026ndash;10 years postoperatively. Similarly, Hlubek and Mundis \u003csup\u003e(\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e)\u003c/sup\u003e noted that the majority of recurrences develop within 6\u0026ndash;18 months after the initial discectomy, emphasizing the early postoperative period as a critical window for recurrence risk.\u003c/p\u003e\u003cp\u003eThe results of this study demonstrate a significant association between higher BMI and an increased risk of recurrence or the need for re-surgery following lumbar spine surgery. Patients with elevated BMI at the time of their initial operation were more likely to experience recurrent symptoms and to require additional surgical intervention.\u003c/p\u003e\u003cp\u003eOur findings are consistent with previous reports identifying obesity as a significant risk factor for postoperative complications and poorer outcomes after spinal procedures. Excess body weight increases intradiscal pressure and spinal instability, which may promote recurrent herniation. In addition to these mechanical effects, obesity is associated with systemic metabolic alterations\u0026mdash;such as chronic low-grade inflammation, impaired microvascular perfusion, and delayed tissue healing\u0026mdash;that may compromise recovery and structural repair following surgery.\u003c/p\u003e\u003cp\u003ePrevious studies examining BMI as a predictor of R-LDH have yielded mixed results. Several investigations compared BMI between recurrent and non-recurrent groups \u003csup\u003e(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan additionalcitationids=\"CR15\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan additionalcitationids=\"CR28\" citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e)\u003c/sup\u003e. For example, studies evaluating BMI\u0026thinsp;\u0026gt;\u0026thinsp;25 kg/m\u0026sup2; found it to be significantly associated with recurrence, with an odds ratio comparable to our result (OR\u0026thinsp;=\u0026thinsp;1.38; 95% CI, 1.17\u0026ndash;1.63; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) \u003csup\u003e(\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e)\u003c/sup\u003e. Similarly, another study reported significantly higher BMI among patients who developed recurrence \u003csup\u003e(\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e)\u003c/sup\u003e, whereas one study did not find a significant association \u003csup\u003e(\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e)\u003c/sup\u003e. Our findings, demonstrating that higher BMI independently predicts recurrence, support the subset of studies suggesting that excessive body weight contributes to poorer surgical outcomes. These results align with biomechanical evidence indicating that obesity increases axial loading on the lumbar spine, elevates compressive and shear forces on intervertebral discs, and impairs paraspinal muscle function, potentially accelerating disc degeneration and predisposing patients to recurrence \u003csup\u003e(\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e)\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eOur results underscore the importance of weight optimization as a modifiable risk factor in patients undergoing lumbar spine procedures. Preoperative counseling and postoperative lifestyle interventions aimed at reducing BMI could play a critical role in improving long-term surgical outcomes and minimizing recurrence rates.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eHigher body mass index (BMI) is significantly associated with recurrence and the need for re-surgery following lumbar discectomy, highlighting excess body weight as a modifiable risk factor. Patients with elevated BMI at the time of their initial operation were more likely to experience postoperative recurrence, emphasizing the importance of incorporating BMI into preoperative risk stratification and postoperative counseling. These findings suggest that preoperative weight optimization and postoperative lifestyle management may improve surgical outcomes and reduce recurrence rates.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eLimitations\u003c/strong\u003e\u003cp\u003eDespite these findings, several limitations should be acknowledged. The retrospective design limits causal inference and may introduce selection bias. Potential confounding factors\u0026mdash;such as comorbidities, variations in surgical technique, adherence to postoperative rehabilitation, and lifestyle factors\u0026mdash;were not controlled in this analysis. Further prospective, multicenter studies are needed to validate these results and to clarify the biomechanical and metabolic mechanisms through which obesity affects spinal pathology and surgical outcomes. Future research should also consider preoperative BMI optimization programs and long-term follow-up to evaluate the impact of BMI changes on the risk of re-surgery.\u003c/p\u003e\u003c/p\u003e"},{"header":"Abbreviations","content":"BMI = Body Mass Index, MRI: Magnetic Resonance Imaging, LDH= Lumbar Disc Herniation, R-LDH= Recurrent-Lumbar Disc Herniation, TNF-α = Tumor Necrosis Factor-alpha, IL-6 = Interleukin-6, IL-1= Interleukin-1, MMP = Matrix Metalloproteinase, WHO =World Health Organization, OECD = the Organization for Economic Co-operation and Development, GOTHI = The General Organization of teaching hospitals and institutes in Egypt."},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEthical approval was obtained from the Ethical and Research Committee in General Organization of teaching hospitals and institutes, Egypt (GOTHI, approval number HAH00034).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConsent to publish obtained from patients to publish their data and imaging.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analysed during this study are included in this published article in the results section.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting Interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors received no specific funding from any public, commercial, or not-for-profit organization for the conduct of this research.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eLean, M. 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(2022).\u0026nbsp;Clinical and radiological risk factors of early recurrent lumbar disc herniation at six months or less: a clinical retrospective analysis in one medical center. \u003cem\u003ePain Physician\u003c/em\u003e, \u003cem\u003e25\u003c/em\u003e(7), E1039\u003c/li\u003e\n \u003cli\u003eSteelman, T., Lewandowski, L., Helgeson, M., Wilson, K., Olsen, C., \u0026amp; Gwinn, D. (2018). Population-based risk factors for the development of degenerative disk disease. \u003cem\u003eClinical Spine Surgery\u003c/em\u003e, \u003cem\u003e31\u003c/em\u003e(8), E409-E412.\u003c/li\u003e\n \u003cli\u003eWatanabe, T., Otani, K., Sekiguchi, M., \u0026amp; Konno, S. I. (2022). Relationship between lumbar disc degeneration on MRI and low back pain: A cross-sectional community study. \u003cem\u003eFukushima Journal of Medical Science\u003c/em\u003e, \u003cem\u003e68\u003c/em\u003e(2), 97-107.\u003c/li\u003e\n \u003cli\u003eJakoi, A. M., Pannu, G., D\u0026apos;Oro, A., Buser, Z., Pham, M. 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Effect of obesity on the development, management, and outcomes of spinal disorders. \u003cem\u003eJAAOS-Journal of the American Academy of Orthopaedic Surgeons\u003c/em\u003e, \u003cem\u003e27\u003c/em\u003e(11), e499-e506.\u003c/li\u003e\n \u003cli\u003eJiang, J., Huang, Y., \u0026amp; He, B. (2024). Advances in the interaction between lumbar intervertebral disc degeneration and fat infiltration of paraspinal muscles: critical summarization, classification, and perspectives. \u003cem\u003eFrontiers in Endocrinology\u003c/em\u003e, \u003cem\u003e15\u003c/em\u003e, 1353087\u003c/li\u003e\n \u003cli\u003eKumar, V., \u0026amp; Kumar, M. (2025). Common Types of Degenerative Spinal Disorders: An Overview. \u003cem\u003eA Comprehensive Guide to Degenerative Spine Disorders\u003c/em\u003e, 37-61.\u003c/li\u003e\n \u003cli\u003eMcDonnell, J. M., Darwish, S., Butler, J. S., \u0026amp; Buckley, C. T. (2025). The Role of Adipokines in Spinal Disease: A Narrative Review. \u003cem\u003eJOR spine\u003c/em\u003e, \u003cem\u003e8\u003c/em\u003e(2), e70083.\u003c/li\u003e\n \u003cli\u003ePierpont, Y. N., Dinh, T. P., Salas, R. E., Johnson, E. L., Wright, T. G., Robson, M. C., \u0026amp; Payne, W. G. (2014). Obesity and surgical wound healing: a current review. \u003cem\u003eInternational Scholarly Research Notices\u003c/em\u003e, \u003cem\u003e2014\u003c/em\u003e(1), 638936.\u003c/li\u003e\n \u003cli\u003ePlassmeier, L., Hankir, M. K., \u0026amp; Seyfried, F. (2021). Impact of excess body weight on postsurgical complications. \u003cem\u003eVisceral medicine\u003c/em\u003e, \u003cem\u003e37\u003c/em\u003e(4), 287-297.\u003c/li\u003e\n \u003cli\u003eShimia, M., Babaei-Ghazani, A., Sadat, B., Habibi, B., \u0026amp; Habibzadeh, A. (2013).\u0026nbsp;Risk factors of recurrent lumbar disk herniation. Asian journal of neurosurgery, 8(02), 93-96.\u003c/li\u003e\n \u003cli\u003eMiwa, S., Yokogawa, A., Kobayashi, T., Nishimura, T., Igarashi, K., Inatani, H., \u0026amp; Tsuchiya, H. (2015). Risk factors of recurrent lumbar disk herniation: a single center study and review of the literature. \u003cem\u003eClinical Spine Surgery\u003c/em\u003e, \u003cem\u003e28\u003c/em\u003e(5), E265-E269.\u003c/li\u003e\n \u003cli\u003eYao, Y., Liu, H., Zhang, H., Wang, H., Zhang, C., Zhang, Z., ... \u0026amp; Zhou, Y. (2017). Risk factors for recurrent herniation after percutaneous endoscopic lumbar discectomy. \u003cem\u003eWorld neurosurgery\u003c/em\u003e, \u003cem\u003e100\u003c/em\u003e, 1-6\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"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":"Body Mass Index, Lumbar Spine Surgery, Recurrence, Re-surgery, Risk Factor","lastPublishedDoi":"10.21203/rs.3.rs-8167610/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8167610/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Obesity is a well-established risk factor for numerous health complications, yet its impact on postoperative recurrence and the need for re-surgery after lumbar spine surgery remains unclear. Lumbar spine surgery is a common treatment for degenerative spinal disorders; however, recurrence of symptoms and subsequent re-surgery continue to pose significant postoperative challenges. Body mass index (BMI) has been suggested as a potential risk factor affecting surgical outcomes due to its biomechanical and metabolic effects. This study aimed to evaluate the association between BMI and the risk of recurrence and re-surgery following lumbar spine surgery.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjective:\u003c/strong\u003e To evaluate the association between BMI and the risk of recurrence and re-surgery after lumbar spine surgery.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e This is a retrospective cohort study that included adult patients who underwent a single stable lumbar spine discectomy for degenerative disc disease at Al-Ahrar Teaching Hospital and Zagazig University Hospitals, Zagazig, Egypt, between January 2015 and October 2025. Patients with multilevel disc pathology, concomitant cervical or thoracic spine disorders, unstable vertebrae, or a history of previous lumbar surgery were excluded. BMI was recorded at the time of the first surgery and at the follow-up.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e The study included 286 patients (171 males and 115 females); we selected 286 cases from the hospital medical records, among more than 5,000 cases operated on during 10 years, with a mean age of 41.9 ± 11.2 years. Recurrence of lumbar surgery occurred in 28 patients (9.8%). Higher BMI was significantly associated with recurrence: 18 (64.3%) of overweight/ obese patients and required re-surgery, compared with 10 (35.7%) of patients with a healthy weight. The mean BMI at the time of the initial surgery was significantly higher in the recurrence group (25.8 ± 2.8 kg/m²) than in the non-recurrence group (22.9 ± 2.0 kg/m²; p \u0026lt; 0.001). Similarly, BMI at follow-up remained greater among patients with recurrence (25.0 ± 2.6 vs. 21.9 ± 2.1 kg/m²; p \u0026lt; 0.001). Obesity-related comorbidities were present in (66.7%) of patients, with type 2 diabetes (24.1%) and cardiovascular disease (18.3%) being the most common.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eHigher BMI is significantly associated with recurrence and need for re-surgery following lumbar spine surgery, identifying elevated BMI as an independent risk factor. BMI should be considered during preoperative risk assessment and postoperative counseling. Implementing weight optimization strategies before and after surgery may improve long-term outcomes and reduce recurrence rates.\u003c/p\u003e","manuscriptTitle":"Body Mass Index as A risk Factor for Recurrence and Frequency of Re-surgery After Lumber Spine Surgery","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-26 09:11:22","doi":"10.21203/rs.3.rs-8167610/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":"6ffb21cf-8024-40dc-be27-70e3487945a2","owner":[],"postedDate":"November 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-11-26T09:11:24+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-26 09:11:22","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8167610","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8167610","identity":"rs-8167610","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}