{"paper_id":"1d2f719c-6675-49a3-819b-e32d5ba37412","body_text":"Radiological and Clinical Outcomes of Expansive LLIF cages – Single- arm and comparative systematic revision with metanalysis | 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 Systematic Review Radiological and Clinical Outcomes of Expansive LLIF cages – Single- arm and comparative systematic revision with metanalysis Elio José Sousa Junior, Luis Marcelo Carvalho Guidão, Igor Silva Vasconcelos, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7273973/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 Purpose Expandable cages have been introduced in lateral lumbar interbody fusion (LLIF) to enhance segmental lordosis correction and reduce endplate damage and subsidence risk. However, evidence regarding their efficacy remains inconsistent. This systematic review and meta-analysis aimed to evaluate the ability of expandable cages to promote segmental lordosis and assess their safety profile, specifically regarding subsidence and complications, compared to static cages. Methods A systematic search of PubMed, Google Scholar, Ovid, and BVS databases was conducted following PRISMA guidelines. Inclusion criteria were original studies using expandable cages in LLIF, reporting on segmental lordosis and/or subsidence. Quality was assessed using the Newcastle–Ottawa Scale. Random-effects meta-analyses with cluster-robust variance estimation and subgroup/meta-regression analyses were performed using R software. Results Nine studies with a total of 414 patients (expandable group) were included. The pooled mean segmental lordosis at last follow-up in the expandable cage group was 8.67° (95% CI: 5.34–11.9°), with no significant influence from preoperative lordosis. When compared to static cages, the mean difference in lordosis was not statistically significant (MD = − 2.56°, p = 0.27). Subsidence rate for expandable cages was 4% (95% CI: 1–15%). A significant reduction in odds of subsidence was observed with expandable cages versus static cages (OR = 0.16; 95% CI: 0.02–0.99, p = 0.049). Overall complication data were inconsistently reported and not pooled. Conclusion Expandable cages in LLIF are associated with low subsidence rates and achieve substantial segmental lordosis correction, although superiority over static cages in lordosis gain remains unproven. These findings support their use for individualized anatomic correction; however, more high-quality, prospective studies are needed to validate their clinical advantages and long-term outcomes. Interbody fusion Expandable devices LLIF Systematic Review Metanalysis Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction The lateral lumbar interbody fusion surgery is a well-stablished technique in scientific literature with a wide array of applications and a well-known safety and efficacy profile[ 1 , 2 ]. Although, the technique has significant potential to correct segmental lordosis and promote neural decompression at the same time, in some cases the balance between lordosis and decompression might be lost, leading to insufficient decompression or insufficient lordosis. Moreover, in some cases while trying to fit the ideal lordotic and taller cage surgeon might promote an oversizing of the disc space leading to endplate injury and postoperative subsidence[ 3 , 4 ]. In order to promote a more tailor-made cage, expandable devices were implemented, which are able to expand inside the disc space, allowing surgeon to fine-tune the cage angulation, and in some more modern devices, the anterior and posterior height, this way allowing for an more patient-specific adjustment, in theory reducing the risks of endplate damage and oversizing of the dispositive. However, the early results of this technology are still heterogenous, with some authors reporting very interesting results, and others reporting similar results (but more expensive surgery) compared to traditional (static) devices[ 5 – 7 ]. Therefore, the aim of the present study is to analyze through a systematic review and metanalysis the ability of expandable devices to promote segmental lordosis increase, and to analyze the rate of general complications and subsidence occurrence compared to static dispositives. Methods Search and Retrieval Strategy The electronic databases, including PubMed, Google Scholar, Ovid, and BVS, will be systematically reviewed using the following search strategy: ((((((Lateral lumbar interbody fusion) OR (LLIF)) OR (LTP)) OR (PTP)) OR (Prone Lateral)) OR (Prone transpsoas)) AND (((((Expandable devices) OR (Expandable cages)) OR (Expandables)) OR (Expansive cages)) OR (Expansive)) Only original articles in English, Portuguese, Chinese, or Spanish will be included in the review. Two authors will screen all retrieved references, and any disputes regarding inclusion will be resolved by mutual consensus. The step-by-step selection process will be illustrated in a flowchart, as recommended by PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses). The study is registered in PROSPERO. Selection and Inclusion Criteria The study selection will be performed in two phases. The first phase will involve a brief review of titles and abstracts, during which the authors will assess whether each study should proceed to the next phase. Articles with ambiguous eligibility will automatically advance to the second phase. In the second phase, a full-text evaluation of the remaining articles will be conducted. The inclusion criteria will consist of: Patients with degenerative spine pathologies; Use of lateral expandable devices; Outcomes related to Subsidence or Segmental Lordosis; Classification as a randomized clinical trial, prospective study, or retrospective study. Data Extraction Two authors will independently extract data from each study. Discrepancies will be settled by consensus. Continuous variables will only be included if the article provides standard deviations or sufficient information for their calculation. Studies with multiple subgroups will be split, and subgroup IDs will be denoted with a suffix (e.g., 949, 949-1). Study Outcomes Primary Outcome: Segmental Lordosis at Last Follow-up Subsidence rate General complications Quality Assessment To assess article quality, the RoB-Risk2 Tool from the Cochrane Foundation will be applied to randomized clinical trials, and the Newcastle–Ottawa Scale (NOS) will be used for prospective and retrospective studies. The risk of bias for each article will be summarized in Table 2 . Two independent authors will apply the tools, and in case of disagreement, the “worst” score will be retained. Sensitivity Analysis A sensitivity analysis will be conducted using the leave-one- out method. Each article will be sequentially removed from the meta-analysis to assess its individual impact on the results. The variation in results will be visualized using a Cleveland dot plot. Furthermore, subgroup analysis will be performed to assess the validity and differences of the results in specific clusters: Preoperative segmental lordosis (for Last FUP segmental lordosis variable) Statistical Analysis All statistical analyses were performed in R (version 4.2) using the metafor package. For all models we chose a random-effects framework and estimated between‐study variance via restricted maximum likelihood (REML). Heterogeneity was quantified by τ² and I², and two‐tailed p-values were interpreted at the α = 0.05 level. For the continuous single-arm meta‐analysis of postoperative segmental lordosis in the expandable‐cage group, we first extracted each study’s mean postoperative angle, its standard deviation, and sample size. These inputs were passed to `escalc()` with `measure = \"MN\"` to calculate yi (the observed mean) and vi (its sampling variance). We then fit a random‐effects model via `rma(yi, vi, method = \"REML\")` to pool the mean lordosis across studies and derive a 95% confidence interval. A forest plot displaying both study-specific and overall estimates was generated with `forest()`, including the pooled mean and its precision. Categorical outcomes, namely the proportion of patients experiencing any complication and the proportion with subsidence within the expandable group—were treated in two alternative ways. First, event counts and sample sizes were entered into `escalc()` with `measure = \"PLO\"` (logit-transformed proportions), applying a continuity correction of 0.5 events per cell and adjusting the denominator by + 1 to include zero‐event studies. Second, the same data were transformed using a Freeman–Tukey double‐arcsine approach (`measure = \"PFT\"`), which inherently accommodates zero cells without an arbitrary constant. In both transformations, yi and vi were calculated on the transformed scale. We then fit separate random‐effects models for each transformation (`rma(yi, vi, method = \"REML\")`) and back-transformed the pooled estimates to the original proportion scale using `transf.ilogit` for logit and `transf.ipft` (with the original sample sizes) for Freeman–Tukey. Forest plots were produced for visual comparison of study‐level and summary proportions. To directly compare the expandable and static groups, we conducted a two-arm meta‐analysis of the mean difference in postoperative lordosis (Expandable – Static). Study-level means, standard deviations, and sample sizes for both groups were provided to `escalc()` with `measure = \"MD\"`, yielding yi (the raw mean difference) and vi (its variance) for each study. A random‐effects model was then fit via `rma(yi, vi, method = \"REML\")`. The resulting pooled mean difference and 95% CI were illustrated in a forest plot with a zero-reference line, such that positive values favored the expandable cage and negative values favored the static cage. We also explored whether baseline (preoperative) segmental lordosis predicted postoperative outcomes via a meta-regression. After computing yi/vi for each study’s postoperative lordosis, we fitted `rma(yi, vi, mods = ~ Preop_SL, method = \"REML\")` to estimate the slope of the relationship between preoperative and postoperative means. A bubble plot generated with `bubble()` displayed each study’s postoperative effect size against its preoperative lordosis, with bubble size proportional to study precision. Finally, to account for potential non-independence from overlapping cohorts, we obtained cluster-robust standard errors using `robust()` clustering on the study identifier, which adjusts the variance-covariance matrix for within-cluster dependence. As an alternative, we fitted a multilevel model with `rma.mv(yi, vi, random = ~ 1 | Study)`, explicitly modeling separate variance components at the study and effect‐size levels. Together, these approaches provided more reliable inference when patient populations may not have been strictly All analyses were conducted in R (version 4.x) using a combination of the **meta** and **metafor** packages, with **clubSandwich** for small‐sample, cluster‐robust corrections. For all random‐effects models we estimated between‐study variance via restricted maximum likelihood (REML) and interpreted two‐tailed p‐values at α = 0.05. Continuous single-arm meta‐analysis: Postoperative segmental lordosis (degrees) in the expandable‐cage group was treated as a single‐arm mean. We extracted each study’s postoperative mean, standard deviation, and sample size. These inputs were supplied directly to **meta**’s `metamean(n, mean, sd, sm=\"M\", method.tau=\"REML\")`, which implements an inverse‐variance–weighted random‐effects model on the raw mean scale. Between‐study heterogeneity (τ²) was estimated by REML, and I² and τ² values were reported. Forest plots were produced with **meta**’s `forest()` function, using `leftlabs`, `rightlabs` and color options to display each study’s mean, 95% confidence interval, and percent weight, along with the pooled mean (red diamond). Single-arm proportion meta‐analysis: The proportion of patients experiencing any complication and the proportion with subsidence in the expandable group were analyzed in two ways. First, we fitted a binomial GLMM on the logit scale via meta’s `metaprop(event, n, method=\"GLMM\", sm=\"PLOGIT\")`, which handles zero‐event studies without continuity corrections. Second, as a sensitivity analysis, we used the Freeman–Tukey double‐arcsine transform via `metaprop(..., method=\"Inverse\", sm=\"PFT\")`. Study‐level transformed effect sizes (TE) and variances (seTE²) were extracted and refit in metafor with `rma(yi, vi, method=\"REML\")`, back‐transforming pooled estimates to the original proportion scale using `transf.ilogit` (GLMM) or `transf.ipft` (PFT). Forest plots compared study‐specific and summary proportions. Comparative binary meta-analysis: To compare subsidence rates between expandable and static cages, we used **meta**’s `metabin(event.e, n.e, event.c, n.c, method=\"GLMM\", sm=\"OR\")`, fitting a GLMM–RE model of the odds ratio on the log scale. Study‐level log‐ORs (TE) and variances (seTE²) were extracted for downstream robust modeling. Cluster-robust small-sample correction: When studies contributed multiple correlated outcomes or shared overlapping cohorts, we fitted a two-level model in metafor via `rma.mv(yi, vi, random = ~ 1 | cluster_id, method = \"REML\")`, then applied clubSandwich´s `vcovCR(..., type = \"CR2\")` and `coef_test(test = \"Satterthwaite\")` to obtain robust standard errors, Satterthwaite df, and p-values. Robust 95% CIs were calculated as estimate ± t₀.₉₇₅(df)×SE. Overlaying robust estimates: To present both the standard GLMM-RE or PFT-RE results and the CR2-robust summary in a single plot, we used **meta**’s `metaadd()` to append the robust summary (with its TE, lower, upper, statistic and p-value) as an additional random-effects row. The final `forest()` call displayed the original diamonds (black) and the CR2-adjusted diamond (red), along with I², τ², and p-values for heterogeneity. Thus ensuring valid estimation and inference for continuous means, single-arm proportions, comparative odds ratios, and accounts for small samples and potential non-independence. Results 250 were retrieved with the search mechanism and 12 others were found via reference search. After the first screening (title/abstract), of the 250 retrieved articles, 217 were discarded, while for the 10 found during the reference search 12 were discarded (mainly due to duplicates with the prior 250 articles). Of the remaining 33 articles, 26 were excluded in the full-text analysis, as for the remaining articles found via reference search none were excluded in this section. Finally, 9 articles were included in the systematic review and metanalysis (Fig. 1 ). Of the included articles, all of them were performed in lateral decubitus, with only two articles performing direct comparison between static and expandable devices. The summary information of each included study can be seen in Table 1 . Table 1 Basic details of the included articles. First_Author Year Decubitus Mean Age Expandable Mean Age Static N Expandable N Static Akihiko Hiyama[ 8 ] 2023 Lateral 71,3 72,3 23 44 Yan Michael Li [ 9 ] 2020 Lateral 61,1 65,5 35 27 Yan Michael Li [ 10 ] 2021 Lateral 58,8 103 Emmanuel Omosor 2023 Lateral 64 5 Gregory Malham [ 11 ] 2022 Lateral 64,9 33 Martin Stienen [ 12 ] 2024 Lateral 61,4 63 Akihiko Hiyama [ 13 ] 2025 Lateral 70,6 51 Yan Michael Li [ 14 ] 2021 Lateral 60,3 12 37 32 Richard Frisch [ 15 ] 2018 Lateral 58,7 10,5 27 29 As for the quality of the included articles, as all were non-randomized cohorts the NOS score was applied, with most of the studies scoring between 5 and 6 points (Table 2 ). A more detailed explanation of each scoring point for each article is available as supplemental material. Table 2 Newcastle-Ottawa score of each article. Study Selection(0–4) Comparability(0–2) Outcome(0–3) Total(0–9) Hiyama 2023 4 / 4 0 / 2 1 / 3 5 / 9 Li 2020 4 / 4 0 / 2 2 / 3 6 / 9 Li 2021 3 / 4 0 / 2 2 / 3 5 / 9 Omosor 2023 3 / 4 0 / 2 0 / 3 3 / 9 Malham 2022 3 / 4 0 / 2 2 / 3 5 / 9 Stienen 2024 3 / 4 0 / 2 0 / 3 3 / 9 Hiyama 2025 3 / 4 0 / 2 1 / 3 4 / 9 Li 2021 ASJ 4 / 4 0 / 2 2 / 3 6 / 9 Frisch 2018 4 / 4 0 / 2 2 / 3 6 / 9 Segmental Lordosis at the Last Follow-up Five articles were included in the analysis of the postoperative segmental lordosis. Given the high heterogeneity of the results and the possible overlap of populations included in some studies, a cluster-robust (CR-1) random effects model was employed. The mean segmental lordosis at the last follow-up estimated from the robust analysis was 8.67° [95% CI = 5.34° − 11.9°, t = 5.12, p = 0.006] (Fig. 2 ). Moreover, the preoperative segmental lordosis did not play a significant role in the postoperative last FUP segmental lordosis (0.28 [95% CI = -1.0;1.6], z = 0.40, p = 0.68) (Fig. 2 ). When comparing last follow-up mean segmental lordosis between expandable and static groups, 2 articles were included, with an important discrepancy between their results (I 2 = 81%), therefore the random effects model was employed. The estimated mean difference effect between the groups was − 2.56 [95% CI = -7.13;2.01, z = -1.10, p = 0.27) (Fig. 3 ). Subsidence rate As for the proportion of subsidence in the expandable cohorts, 8 studies were included. Given the low heterogeneity between the groups (I 2 = 0%) a common effect model with robust covariance estimation (RVE) was employed. The estimate proportion of subsidence was 0.04 [95% CI = 0.01;0.15]). (Fig. 4 ). Finally, when comparing the ratios of subsidence between expandable and static groups, 3 studies were included, with almost no heterogeneity between the results (I 2 = 0%), so a common effects model was used. A significant difference was seen between the groups with an odds ratio of 0.16 ([95% CI = 0.02; 0.99], z = -12.69, p = 0.049). (Fig. 5 ). Discussion The use of expandable interbody fusion techniques are increasing in literature, given the potential ability of this dispostives to present a more tailor-made approach for each patient. Unlike static cages, expandable devices allow intraoperative modulation of both disc height and lordotic angle, facilitating precise correction of sagittal alignment at the index level[ 6 , 7 ]. Comparative studies consistently show that expandable cages exhibit lower subsidence rates than static interbody devices in lateral approaches. In minimally invasive lateral lumbar fusion, the use of height and lordosis adjustable cages was associated with a significant reduction in endplate breach and subsidence events compared to rigid PEEK or titanium implants[ 16 ]. Beyond lordosis correction, expandable cages offer theoretical and demonstrated benefits in indirect decompression by restoring foraminal and canal dimensions without posterior element removal. Clinical radiographic series have shown that expandable spacers significantly increase anterior and posterior disc height as well as neuroforaminal height, translating into relief of radicular symptoms through ligamentotaxis [ 10 ]. Early data from 2025 further highlight that enhanced segmental lordosis achieved by expandable devices correlates with spontaneous enlargement of spinal canal area, obviating direct decompression in select LLIF and PTP cases[ 17 ]. Despite these advantages, expandable cages introduce unique device-related risks that merit careful consideration. The internal architecture of many expandable designs precludes packing with autologous bone graft, raising theoretical concerns about fusion potential and demanding long‐term outcome data[ 6 , 7 ]. Moreover, overexpansion can precipitate endplate violation or device failure, causing loss of disc height correction, which might lead to restenosis or loss of lordosis[ 18 , 19 ]. Limitations The present review is not without limitations, with its main two challenges being the small number of studies and the absence of higher quality randomized controlled studies. Conclusion The present study presents a updated review of the use of expandable technology in lateral lumbar interbody fusion techniques, showing that this devices might lead to a reduction in the occurrence of subsidence compared to static cages, and to a significant enhancement of segmental lordosis after surgery, however not significantly higher than the static group. Future studies with more patients and higher levels of evidence (such as randomized controlled studies) should be performed so a more precise estimation of the expandable cages effect in segmental lordosis and subsidence reduction can be performed. Declarations Funding: The authors declare that no funds, grants, or other support were received during the preparation of this manuscript Competing Interests: The authors have no relevant financial or non-financial interests to disclose. Author Contributions: EJ - Manuscript design, writing and revision LMCG - Manuscript writing and revision ISV - Manuscript writing and revision GP - Manuscript design, revision, statical analysis and image creation Ethics approval: This is a systematic revision study; therefore, no previous IRB approval was needed. Clinical trial number : not applicable. References Ozgur BM, Aryan HE, Pimenta L, Taylor WR (2006) Extreme Lateral Interbody Fusion (XLIF): a novel surgical technique for anterior lumbar interbody fusion. Spine Journal 6:435–443 Pimenta L, Marchi L, Oliveira L, Fortti F, Coutinho E, Jensen R, Amaral R (2017) History and Rationale for the Minimally Invasive Lateral Approach. Lateral Access Minimally Invasive Spine Surgery 3–9 Malham GM, Parker RM, Goss B, Blecher CM (2015) Clinical results and limitations of indirect decompression in spinal stenosis with laterally implanted interbody cages: results from a prospective cohort study. European Spine Journal 24:339–345 Lang G, Perrech M, Navarro-Ramirez R, Hussain I, Pennicooke B, Maryam F, Avila MJ, Härtl R (2017) Potential and Limitations of Neural Decompression in Extreme Lateral Interbody Fusion—A Systematic Review. World Neurosurg 101:99–113 Beyer RS, Shooshani T, Batista B, Fraipont GM, Pooladzandi O, Brown NJ, Pennington Z, Pham MH (2024) Static Versus Expandable Cages in Minimally Invasive Lateral Lumbar Interbody Fusion. Clin Spine Surg. https://doi.org/10.1097/BSD.0000000000001737 Mao Y, Patel AA, Meade S, Benzel E, Steinmetz MP, Mroz T, Habboub G (2024) Review of mechanisms of expandable spine surgery devices. Expert Rev Med Devices 21:381–390 Lee S Bin, Yoon J, Park SJ, Chae DS (2024) Expandable Cages for Lumbar Interbody Fusion: A Narrative Review. Journal of Clinical Medicine 2024, Vol 13, Page 2889 13:2889 Hiyama A, Katoh H, Sakai D, Sato M, Watanabe M (2023) Early Radiological Assessment of Static and Expandable Cages in Lateral Single Position for Indirect Decompression- Lateral Lumbar Interbody Fusion. World Neurosurg 178:e453–e464 Li YM, Frisch RF, Huang Z, Towner J, Li YI, Greeley SL, Ledonio C (2020) Comparative Effectiveness of Expandable Versus Static Interbody Spacers via MIS LLIF: A 2-Year Radiographic and Clinical Outcomes Study. Global Spine J 10:998–1005 Li YM, Huang Z, Towner J, Li YI, Riggleman JR, Ledonio C (2021) Expandable Technology Improves Clinical and Radiographic Outcomes of Minimally Invasive Lateral Lumbar Interbody Fusion for Degenerative Disc Disease. Int J Spine Surg 15:87 Malham GM, Blecher CM, Munday NR, Hamer RP (2022) Expandable Lateral Lumbar Cages With Integrated Fixation: A Viable Option for Rostral Adjacent Segment Disease. Int J Spine Surg 16:748–759 Stienen MN, Fischer G, Bättig L, Veeravagu A, Martens B (2024) Minimally-invasive lateral thoracic and lumbar interbody fusion (LLIF) with expandable interbody cages – Considerations, complications & outcomes. Brain & Spine 4:102870 Hiyama A, Sakai D, Katoh H, Sato M, Watanabe M (2025) Segmental Lordosis and Disc Height Discrepancies in Lateral Lumbar Interbody Fusion Using Expandable Cages. Int J Spine Surg 19:188–199 Li YM, Frisch RF, Huang Z, Towner JE, Li YI, Edsall AL, Ledonio C (2021) Comparative Effectiveness of Laterally Placed Expandable versus Static Interbody Spacers: A 1-Year Follow-Up Radiographic and Clinical Outcomes Study. Asian Spine J 15:89–96 Frisch RF, Luna IY, Brooks DM, Joshua G, O’Brien JR (2018) Clinical and radiographic analysis of expandable versus static lateral lumbar interbody fusion devices with two-year follow-up. J Spine Surg 4:62–71 Calvachi-Prieto P, McAvoy MB, Cerecedo-Lopez CD, et al (2021) Expandable Versus Static Cages in Minimally Invasive Lumbar Interbody Fusion: A Systematic Review and Meta-Analysis. World Neurosurg 151:e607–e614 Hiyama A, Sakai D, Katoh H, Sato M, Watanabe M (2025) Lumbar Interbody Fusion Using Expandable Cages Segmental Lordosis and Disc Height Discrepancies in Lateral. https://doi.org/10.14444/8726 Kirnaz S, Navarro-Ramirez R, Gu J, et al (2020) Indirect Decompression Failure After Lateral Lumbar Interbody Fusion—Reported Failures and Predictive Factors: Systematic Review. Global Spine J 10:8S ElNemer W, Kim A, Silva-Aponte J, Raad M, Azad T, Durand WM, Hassanzadeh H, Kebaish K, Jain A (2025) An Analysis of the Complication Reports of Expandable Lumbar Interbody Cages in the Food and Drug Administration Manufacturer and User Facility Device Experience Database. Orthopedics 48:e7–e14 Additional Declarations Competing interest reported. Gabriel Pokorny receives consutancy fees from ATEC Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {\"props\":{\"pageProps\":{\"initialData\":{\"identity\":\"rs-7273973\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":true,\"archivedVersions\":[],\"articleType\":\"Systematic Review\",\"associatedPublications\":[],\"authors\":[{\"id\":526704999,\"identity\":\"9cc39351-be09-48b6-afe6-43405b005d33\",\"order_by\":0,\"name\":\"Elio José Sousa Junior\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Instituto de Traumatologia e Ortopedia de São Paulo\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Elio\",\"middleName\":\"José 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14:05:21\",\"extension\":\"png\",\"order_by\":1,\"title\":\"Figure 1\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":176856,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003ePRISMA workflow detailing the studies screening.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"1.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-7273973/v1/f980ba7936caf954694ce4ce.png\"},{\"id\":93335121,\"identity\":\"11162aee-84d0-4f41-96c9-32ca2315fe1e\",\"added_by\":\"auto\",\"created_at\":\"2025-10-12 13:57:21\",\"extension\":\"png\",\"order_by\":2,\"title\":\"Figure 2\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":286649,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eForest plot of last follow-up mean segmental lordosis in the expandable group. MD: Mean Difference, SE: Standard Error; CI: Confidence Interval; RE: Random Effects; RVE: Random Variance Estimator.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"2.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-7273973/v1/6c1d5c3b94bf8f8b35f89205.png\"},{\"id\":93335123,\"identity\":\"ccd6feb0-0fe9-4fd0-8458-136206b82fd6\",\"added_by\":\"auto\",\"created_at\":\"2025-10-12 13:57:21\",\"extension\":\"png\",\"order_by\":3,\"title\":\"Figure 3\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":162336,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eForest plot of last follow-up mean segmental lordosis in the expandable group versus control group. MD: Mean Difference, SE: Standard Error; CI: Confidence Interval; RE: Random Effects; RVE: Random Variance Estimator.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"3.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-7273973/v1/fe03c6f85c00a5ec29bfe051.png\"},{\"id\":93335132,\"identity\":\"28862094-a7e2-47f9-9535-6c6a73481eb6\",\"added_by\":\"auto\",\"created_at\":\"2025-10-12 13:57:21\",\"extension\":\"png\",\"order_by\":4,\"title\":\"Figure 4\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":396643,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eForest plot of subsidence proportion in the expandable group with a CR-2 Robust Common-effects model: Confidence Interval; RE: Random Effects.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"4.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-7273973/v1/302e333406d22ee430b437ed.png\"},{\"id\":93337907,\"identity\":\"c6f75927-5f7b-40f0-9c2f-c61383de8f42\",\"added_by\":\"auto\",\"created_at\":\"2025-10-12 14:13:21\",\"extension\":\"png\",\"order_by\":5,\"title\":\"Figure 5\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":214897,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eForest plot of odds ratio of subsidence in the expandable group versus static group (control) with a CR-2 Robust Common-effects model: Confidence Interval; RE: Random Effects.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"5.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-7273973/v1/48a2384329b0507e8754ef5d.png\"},{\"id\":95835340,\"identity\":\"1aac66bc-0879-4b5d-85b7-7a8b7041e253\",\"added_by\":\"auto\",\"created_at\":\"2025-11-13 13:09:05\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":1737032,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-7273973/v1/b5522d5e-35c4-4977-a90e-e161fe5606db.pdf\"}],\"financialInterests\":\"Competing interest reported. Gabriel Pokorny receives consutancy fees from ATEC\",\"formattedTitle\":\"Radiological and Clinical Outcomes of Expansive LLIF cages – Single- arm and comparative systematic revision with metanalysis\",\"fulltext\":[{\"header\":\"Introduction\",\"content\":\"\\u003cp\\u003eThe lateral lumbar interbody fusion surgery is a well-stablished technique in scientific literature with a wide array of applications and a well-known safety and efficacy profile[\\u003cspan citationid=\\\"CR1\\\" class=\\\"CitationRef\\\"\\u003e1\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e].\\u003c/p\\u003e\\u003cp\\u003eAlthough, the technique has significant potential to correct segmental lordosis and promote neural decompression at the same time, in some cases the balance between lordosis and decompression might be lost, leading to insufficient decompression or insufficient lordosis. Moreover, in some cases while trying to fit the ideal lordotic and taller cage surgeon might promote an oversizing of the disc space leading to endplate injury and postoperative subsidence[\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e].\\u003c/p\\u003e\\u003cp\\u003eIn order to promote a more tailor-made cage, expandable devices were implemented, which are able to expand inside the disc space, allowing surgeon to fine-tune the cage angulation, and in some more modern devices, the anterior and posterior height, this way allowing for an more patient-specific adjustment, in theory reducing the risks of endplate damage and oversizing of the dispositive. However, the early results of this technology are still heterogenous, with some authors reporting very interesting results, and others reporting similar results (but more expensive surgery) compared to traditional (static) devices[\\u003cspan additionalcitationids=\\\"CR6\\\" citationid=\\\"CR5\\\" class=\\\"CitationRef\\\"\\u003e5\\u003c/span\\u003e–\\u003cspan citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e].\\u003c/p\\u003e\\u003cp\\u003eTherefore, the aim of the present study is to analyze through a systematic review and metanalysis the ability of expandable devices to promote segmental lordosis increase, and to analyze the rate of general complications and subsidence occurrence compared to static dispositives.\\u003c/p\\u003e\"},{\"header\":\"Methods\",\"content\":\"\\u003cp\\u003eSearch and Retrieval Strategy\\u003c/p\\u003e\\u003cp\\u003eThe electronic databases, including PubMed, Google Scholar, Ovid, and BVS, will be systematically reviewed using the following search strategy:\\u003c/p\\u003e\\u003cp\\u003e((((((Lateral lumbar interbody fusion) OR (LLIF)) OR (LTP)) OR (PTP)) OR (Prone Lateral)) OR (Prone transpsoas)) AND (((((Expandable devices) OR (Expandable cages)) OR (Expandables)) OR (Expansive cages)) OR (Expansive))\\u003c/p\\u003e\\u003cp\\u003eOnly original articles in English, Portuguese, Chinese, or Spanish will be included in the review. Two authors will screen all retrieved references, and any disputes regarding inclusion will be resolved by mutual consensus. The step-by-step selection process will be illustrated in a flowchart, as recommended by PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses). The study is registered in PROSPERO.\\u003c/p\\u003e\\u003cp\\u003eSelection and Inclusion Criteria\\u003c/p\\u003e\\u003cp\\u003eThe study selection will be performed in two phases. The first phase will involve a brief review of titles and abstracts, during which the authors will assess whether each study should proceed to the next phase. Articles with ambiguous eligibility will automatically advance to the second phase.\\u003c/p\\u003e\\u003cp\\u003eIn the second phase, a full-text evaluation of the remaining articles will be conducted. The inclusion criteria will consist of:\\u003c/p\\u003e\\u003cp\\u003ePatients with degenerative spine pathologies;\\u003c/p\\u003e\\u003cp\\u003eUse of lateral expandable devices;\\u003c/p\\u003e\\u003cp\\u003eOutcomes related to Subsidence or Segmental Lordosis;\\u003c/p\\u003e\\u003cp\\u003eClassification as a randomized clinical trial, prospective study, or retrospective study.\\u003c/p\\u003e\\u003cp\\u003eData Extraction\\u003c/p\\u003e\\u003cp\\u003eTwo authors will independently extract data from each study. Discrepancies will be settled by consensus. Continuous variables will only be included if the article provides standard deviations or sufficient information for their calculation. Studies with multiple subgroups will be split, and subgroup IDs will be denoted with a suffix (e.g., 949, 949-1).\\u003c/p\\u003e\\u003cp\\u003eStudy Outcomes\\u003c/p\\u003e\\u003cp\\u003ePrimary Outcome:\\u003c/p\\u003e\\u003cp\\u003eSegmental Lordosis at Last Follow-up\\u003c/p\\u003e\\u003cp\\u003eSubsidence rate\\u003c/p\\u003e\\u003cp\\u003eGeneral complications\\u003c/p\\u003e\\u003cp\\u003eQuality Assessment\\u003c/p\\u003e\\u003cp\\u003eTo assess article quality, the RoB-Risk2 Tool from the Cochrane Foundation will be applied to randomized clinical trials, and the Newcastle–Ottawa Scale (NOS) will be used for prospective and retrospective studies. The risk of bias for each article will be summarized in Table\\u0026nbsp;\\u003cspan refid=\\\"Tab2\\\" class=\\\"InternalRef\\\"\\u003e2\\u003c/span\\u003e. Two independent authors will apply the tools, and in case of disagreement, the “worst” score will be retained.\\u003c/p\\u003e\\u003cp\\u003eSensitivity Analysis\\u003c/p\\u003e\\u003cp\\u003eA sensitivity analysis will be conducted using the leave-one- out method. Each article will be sequentially removed from the meta-analysis to assess its individual impact on the results. The variation in results will be visualized using a Cleveland dot plot.\\u003c/p\\u003e\\u003cp\\u003eFurthermore, subgroup analysis will be performed to assess the validity and differences of the results in specific clusters:\\u003c/p\\u003e\\u003cp\\u003ePreoperative segmental lordosis (for Last FUP segmental lordosis variable)\\u003c/p\\u003e\\u003ch2\\u003eStatistical Analysis\\u003c/h2\\u003e\\u003cp\\u003eAll statistical analyses were performed in R (version 4.2) using the metafor package. For all models we chose a random-effects framework and estimated between‐study variance via restricted maximum likelihood (REML). Heterogeneity was quantified by τ² and I², and two‐tailed p-values were interpreted at the α = 0.05 level.\\u003c/p\\u003e\\u003cp\\u003eFor the continuous single-arm meta‐analysis of postoperative segmental lordosis in the expandable‐cage group, we first extracted each study’s mean postoperative angle, its standard deviation, and sample size. These inputs were passed to `escalc()` with `measure = \\\"MN\\\"` to calculate yi (the observed mean) and vi (its sampling variance). We then fit a random‐effects model via `rma(yi, vi, method = \\\"REML\\\")` to pool the mean lordosis across studies and derive a 95% confidence interval. A forest plot displaying both study-specific and overall estimates was generated with `forest()`, including the pooled mean and its precision.\\u003c/p\\u003e\\u003cp\\u003eCategorical outcomes, namely the proportion of patients experiencing any complication and the proportion with subsidence within the expandable group—were treated in two alternative ways. First, event counts and sample sizes were entered into `escalc()` with `measure = \\\"PLO\\\"` (logit-transformed proportions), applying a continuity correction of 0.5 events per cell and adjusting the denominator by + 1 to include zero‐event studies. Second, the same data were transformed using a Freeman–Tukey double‐arcsine approach (`measure = \\\"PFT\\\"`), which inherently accommodates zero cells without an arbitrary constant. In both transformations, yi and vi were calculated on the transformed scale. We then fit separate random‐effects models for each transformation (`rma(yi, vi, method = \\\"REML\\\")`) and back-transformed the pooled estimates to the original proportion scale using `transf.ilogit` for logit and `transf.ipft` (with the original sample sizes) for Freeman–Tukey. Forest plots were produced for visual comparison of study‐level and summary proportions.\\u003c/p\\u003e\\u003cp\\u003eTo directly compare the expandable and static groups, we conducted a two-arm meta‐analysis of the mean difference in postoperative lordosis (Expandable – Static). Study-level means, standard deviations, and sample sizes for both groups were provided to `escalc()` with `measure = \\\"MD\\\"`, yielding yi (the raw mean difference) and vi (its variance) for each study. A random‐effects model was then fit via `rma(yi, vi, method = \\\"REML\\\")`. The resulting pooled mean difference and 95% CI were illustrated in a forest plot with a zero-reference line, such that positive values favored the expandable cage and negative values favored the static cage.\\u003c/p\\u003e\\u003cp\\u003eWe also explored whether baseline (preoperative) segmental lordosis predicted postoperative outcomes via a meta-regression. After computing yi/vi for each study’s postoperative lordosis, we fitted `rma(yi, vi, mods = ~ Preop_SL, method = \\\"REML\\\")` to estimate the slope of the relationship between preoperative and postoperative means. A bubble plot generated with `bubble()` displayed each study’s postoperative effect size against its preoperative lordosis, with bubble size proportional to study precision.\\u003c/p\\u003e\\u003cp\\u003eFinally, to account for potential non-independence from overlapping cohorts, we obtained cluster-robust standard errors using `robust()` clustering on the study identifier, which adjusts the variance-covariance matrix for within-cluster dependence. As an alternative, we fitted a multilevel model with `rma.mv(yi, vi, random = ~ 1 | Study)`, explicitly modeling separate variance components at the study and effect‐size levels. Together, these approaches provided more reliable inference when patient populations may not have been strictly All analyses were conducted in R (version 4.x) using a combination of the **meta** and **metafor** packages, with **clubSandwich** for small‐sample, cluster‐robust corrections. For all random‐effects models we estimated between‐study variance via restricted maximum likelihood (REML) and interpreted two‐tailed p‐values at α = 0.05.\\u003c/p\\u003e\\u003cp\\u003eContinuous single-arm meta‐analysis: Postoperative segmental lordosis (degrees) in the expandable‐cage group was treated as a single‐arm mean. We extracted each study’s postoperative mean, standard deviation, and sample size. These inputs were supplied directly to **meta**’s `metamean(n, mean, sd, sm=\\\"M\\\", method.tau=\\\"REML\\\")`, which implements an inverse‐variance–weighted random‐effects model on the raw mean scale. Between‐study heterogeneity (τ²) was estimated by REML, and I² and τ² values were reported. Forest plots were produced with **meta**’s `forest()` function, using `leftlabs`, `rightlabs` and color options to display each study’s mean, 95% confidence interval, and percent weight, along with the pooled mean (red diamond).\\u003c/p\\u003e\\u003cp\\u003eSingle-arm proportion meta‐analysis: The proportion of patients experiencing any complication and the proportion with subsidence in the expandable group were analyzed in two ways. First, we fitted a binomial GLMM on the logit scale via meta’s `metaprop(event, n, method=\\\"GLMM\\\", sm=\\\"PLOGIT\\\")`, which handles zero‐event studies without continuity corrections. Second, as a sensitivity analysis, we used the Freeman–Tukey double‐arcsine transform via `metaprop(..., method=\\\"Inverse\\\", sm=\\\"PFT\\\")`. Study‐level transformed effect sizes (TE) and variances (seTE²) were extracted and refit in metafor with `rma(yi, vi, method=\\\"REML\\\")`, back‐transforming pooled estimates to the original proportion scale using `transf.ilogit` (GLMM) or `transf.ipft` (PFT). Forest plots compared study‐specific and summary proportions.\\u003c/p\\u003e\\u003cp\\u003eComparative binary meta-analysis: To compare subsidence rates between expandable and static cages, we used **meta**’s `metabin(event.e, n.e, event.c, n.c, method=\\\"GLMM\\\", sm=\\\"OR\\\")`, fitting a GLMM–RE model of the odds ratio on the log scale. Study‐level log‐ORs (TE) and variances (seTE²) were extracted for downstream robust modeling.\\u003c/p\\u003e\\u003cp\\u003eCluster-robust small-sample correction: When studies contributed multiple correlated outcomes or shared overlapping cohorts, we fitted a two-level model in metafor via `rma.mv(yi, vi, random = ~ 1 | cluster_id, method = \\\"REML\\\")`, then applied clubSandwich´s `vcovCR(..., type = \\\"CR2\\\")` and `coef_test(test = \\\"Satterthwaite\\\")` to obtain robust standard errors, Satterthwaite df, and p-values. Robust 95% CIs were calculated as estimate ± t₀.₉₇₅(df)×SE.\\u003c/p\\u003e\\u003cp\\u003eOverlaying robust estimates: To present both the standard GLMM-RE or PFT-RE results and the CR2-robust summary in a single plot, we used **meta**’s `metaadd()` to append the robust summary (with its TE, lower, upper, statistic and p-value) as an additional random-effects row. The final `forest()` call displayed the original diamonds (black) and the CR2-adjusted diamond (red), along with I², τ², and p-values for heterogeneity. Thus ensuring valid estimation and inference for continuous means, single-arm proportions, comparative odds ratios, and accounts for small samples and potential non-independence.\\u003c/p\\u003e\"},{\"header\":\"Results\",\"content\":\"\\u003cp\\u003e250 were retrieved with the search mechanism and 12 others were found via reference search. After the first screening (title/abstract), of the 250 retrieved articles, 217 were discarded, while for the 10 found during the reference search 12 were discarded (mainly due to duplicates with the prior 250 articles). Of the remaining 33 articles, 26 were excluded in the full-text analysis, as for the remaining articles found via reference search none were excluded in this section. Finally, 9 articles were included in the systematic review and metanalysis (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003e).\\u003c/p\\u003e\\u003cp\\u003e\\u003c/p\\u003e\\u003cp\\u003eOf the included articles, all of them were performed in lateral decubitus, with only two articles performing direct comparison between static and expandable devices. The summary information of each included study can be seen in Table \\u003cspan refid=\\\"Tab1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003e.\\u003c/p\\u003e\\u003cp\\u003e\\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab1\\\" border=\\\"1\\\"\\u003e\\u003ccaption language=\\\"En\\\"\\u003e\\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 1\\u003c/div\\u003e\\u003cdiv class=\\\"CaptionContent\\\"\\u003e\\u003cp\\u003eBasic details of the included articles. \\u003c/p\\u003e\\u003c/div\\u003e\\u003c/caption\\u003e\\u003ccolgroup cols=\\\"7\\\"\\u003e\\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e\\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e\\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e\\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e\\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e\\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c6\\\" colnum=\\\"6\\\"\\u003e\\u003c/div\\u003e\\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c7\\\" colnum=\\\"7\\\"\\u003e\\u003c/div\\u003e\\u003cthead\\u003e\\u003ctr\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003eFirst_Author\\u003c/p\\u003e\\u003c/th\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003eYear\\u003c/p\\u003e\\u003c/th\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003eDecubitus\\u003c/p\\u003e\\u003c/th\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003eMean Age Expandable\\u003c/p\\u003e\\u003c/th\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003eMean Age Static\\u003c/p\\u003e\\u003c/th\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e\\u003cp\\u003eN Expandable\\u003c/p\\u003e\\u003c/th\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c7\\\"\\u003e\\u003cp\\u003eN Static\\u003c/p\\u003e\\u003c/th\\u003e\\u003c/tr\\u003e\\u003c/thead\\u003e\\u003ctbody\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003eAkihiko Hiyama[\\u003cspan citationid=\\\"CR8\\\" class=\\\"CitationRef\\\"\\u003e8\\u003c/span\\u003e]\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e2023\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003eLateral\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e71,3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e72,3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e\\u003cp\\u003e23\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e\\u003cp\\u003e44\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003eYan Michael Li [\\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e]\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e2020\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003eLateral\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e61,1\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e65,5\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e\\u003cp\\u003e35\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e\\u003cp\\u003e27\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003eYan Michael Li [\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e]\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e2021\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003eLateral\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e58,8\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e\\u003cp\\u003e103\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003eEmmanuel Omosor\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e2023\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003eLateral\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e64\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e\\u003cp\\u003e5\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003eGregory Malham [\\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e]\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e2022\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003eLateral\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e64,9\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e\\u003cp\\u003e33\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003eMartin Stienen [\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e]\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e2024\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003eLateral\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e61,4\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e\\u003cp\\u003e63\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003eAkihiko Hiyama [\\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e]\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e2025\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003eLateral\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e70,6\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e\\u003cp\\u003e51\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003eYan Michael Li [\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e]\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e2021\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003eLateral\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e60,3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e12\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e\\u003cp\\u003e37\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e\\u003cp\\u003e32\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003eRichard Frisch [\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e]\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e2018\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003eLateral\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e58,7\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e10,5\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e\\u003cp\\u003e27\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e\\u003cp\\u003e29\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003c/tbody\\u003e\\u003c/colgroup\\u003e\\u003c/table\\u003e\\u003c/div\\u003e\\u003c/p\\u003e\\u003cp\\u003eAs for the quality of the included articles, as all were non-randomized cohorts the NOS score was applied, with most of the studies scoring between 5 and 6 points (Table\\u0026nbsp;\\u003cspan refid=\\\"Tab2\\\" class=\\\"InternalRef\\\"\\u003e2\\u003c/span\\u003e). A more detailed explanation of each scoring point for each article is available as supplemental material.\\u003c/p\\u003e\\u003cp\\u003e\\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab2\\\" border=\\\"1\\\"\\u003e\\u003ccaption language=\\\"En\\\"\\u003e\\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 2\\u003c/div\\u003e\\u003cdiv class=\\\"CaptionContent\\\"\\u003e\\u003cp\\u003eNewcastle-Ottawa score of each article.\\u003c/p\\u003e\\u003c/div\\u003e\\u003c/caption\\u003e\\u003ccolgroup cols=\\\"5\\\"\\u003e\\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e\\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e\\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e\\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e\\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e\\u003cthead\\u003e\\u003ctr\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003eStudy\\u003c/p\\u003e\\u003c/th\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003eSelection(0\\u0026ndash;4)\\u003c/p\\u003e\\u003c/th\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003eComparability(0\\u0026ndash;2)\\u003c/p\\u003e\\u003c/th\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003eOutcome(0\\u0026ndash;3)\\u003c/p\\u003e\\u003c/th\\u003e\\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003eTotal(0\\u0026ndash;9)\\u003c/p\\u003e\\u003c/th\\u003e\\u003c/tr\\u003e\\u003c/thead\\u003e\\u003ctbody\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003eHiyama 2023\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e4\\u0026thinsp;/\\u0026thinsp;4\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003e0\\u0026thinsp;/\\u0026thinsp;2\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e1\\u0026thinsp;/\\u0026thinsp;3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003e5\\u0026thinsp;/\\u0026thinsp;9\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003eLi 2020\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e4\\u0026thinsp;/\\u0026thinsp;4\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003e0\\u0026thinsp;/\\u0026thinsp;2\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e2\\u0026thinsp;/\\u0026thinsp;3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003e6\\u0026thinsp;/\\u0026thinsp;9\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003eLi 2021\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e3\\u0026thinsp;/\\u0026thinsp;4\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003e0\\u0026thinsp;/\\u0026thinsp;2\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e2\\u0026thinsp;/\\u0026thinsp;3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003e5\\u0026thinsp;/\\u0026thinsp;9\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003eOmosor 2023\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e3\\u0026thinsp;/\\u0026thinsp;4\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003e0\\u0026thinsp;/\\u0026thinsp;2\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e0\\u0026thinsp;/\\u0026thinsp;3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003e3\\u0026thinsp;/\\u0026thinsp;9\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003eMalham 2022\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e3\\u0026thinsp;/\\u0026thinsp;4\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003e0\\u0026thinsp;/\\u0026thinsp;2\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e2\\u0026thinsp;/\\u0026thinsp;3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003e5\\u0026thinsp;/\\u0026thinsp;9\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003eStienen 2024\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e3\\u0026thinsp;/\\u0026thinsp;4\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003e0\\u0026thinsp;/\\u0026thinsp;2\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e0\\u0026thinsp;/\\u0026thinsp;3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003e3\\u0026thinsp;/\\u0026thinsp;9\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003eHiyama 2025\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e3\\u0026thinsp;/\\u0026thinsp;4\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003e0\\u0026thinsp;/\\u0026thinsp;2\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e1\\u0026thinsp;/\\u0026thinsp;3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003e4\\u0026thinsp;/\\u0026thinsp;9\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003eLi 2021 ASJ\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e4\\u0026thinsp;/\\u0026thinsp;4\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003e0\\u0026thinsp;/\\u0026thinsp;2\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e2\\u0026thinsp;/\\u0026thinsp;3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003e6\\u0026thinsp;/\\u0026thinsp;9\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003ctr\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003eFrisch 2018\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u003cp\\u003e4\\u0026thinsp;/\\u0026thinsp;4\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u003cp\\u003e0\\u0026thinsp;/\\u0026thinsp;2\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u003cp\\u003e2\\u0026thinsp;/\\u0026thinsp;3\\u003c/p\\u003e\\u003c/td\\u003e\\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u003cp\\u003e\\u003cb\\u003e6\\u0026thinsp;/\\u0026thinsp;9\\u003c/b\\u003e\\u003c/p\\u003e\\u003c/td\\u003e\\u003c/tr\\u003e\\u003c/tbody\\u003e\\u003c/colgroup\\u003e\\u003c/table\\u003e\\u003c/div\\u003e\\u003c/p\\u003e\\u003cp\\u003e\\u003cb\\u003eSegmental Lordosis at the Last Follow-up\\u003c/b\\u003e\\u003c/p\\u003e\\u003cp\\u003eFive articles were included in the analysis of the postoperative segmental lordosis. Given the high heterogeneity of the results and the possible overlap of populations included in some studies, a cluster-robust (CR-1) random effects model was employed. The mean segmental lordosis at the last follow-up estimated from the robust analysis was 8.67\\u0026deg; [95% CI\\u0026thinsp;=\\u0026thinsp;5.34\\u0026deg; \\u0026minus;\\u0026thinsp;11.9\\u0026deg;, t\\u0026thinsp;=\\u0026thinsp;5.12, p\\u0026thinsp;=\\u0026thinsp;0.006] (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig2\\\" class=\\\"InternalRef\\\"\\u003e2\\u003c/span\\u003e). Moreover, the preoperative segmental lordosis did not play a significant role in the postoperative last FUP segmental lordosis (0.28 [95% CI = -1.0;1.6], z\\u0026thinsp;=\\u0026thinsp;0.40, p\\u0026thinsp;=\\u0026thinsp;0.68) (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig2\\\" class=\\\"InternalRef\\\"\\u003e2\\u003c/span\\u003e).\\u003c/p\\u003e\\u003cp\\u003e\\u003c/p\\u003e\\u003cp\\u003eWhen comparing last follow-up mean segmental lordosis between expandable and static groups, 2 articles were included, with an important discrepancy between their results (I\\u003csup\\u003e2\\u003c/sup\\u003e\\u0026thinsp;=\\u0026thinsp;81%), therefore the random effects model was employed. The estimated mean difference effect between the groups was \\u0026minus;\\u0026thinsp;2.56 [95% CI = -7.13;2.01, z = -1.10, p\\u0026thinsp;=\\u0026thinsp;0.27) (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig3\\\" class=\\\"InternalRef\\\"\\u003e3\\u003c/span\\u003e).\\u003c/p\\u003e\\u003cp\\u003e\\u003c/p\\u003e\\u003cp\\u003e\\u003cb\\u003eSubsidence rate\\u003c/b\\u003e\\u003c/p\\u003e\\u003cp\\u003eAs for the proportion of subsidence in the expandable cohorts, 8 studies were included. Given the low heterogeneity between the groups (I\\u003csup\\u003e2\\u003c/sup\\u003e\\u0026thinsp;=\\u0026thinsp;0%) a common effect model with robust covariance estimation (RVE) was employed. The estimate proportion of subsidence was 0.04 [95% CI\\u0026thinsp;=\\u0026thinsp;0.01;0.15]). (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig4\\\" class=\\\"InternalRef\\\"\\u003e4\\u003c/span\\u003e).\\u003c/p\\u003e\\u003cp\\u003e\\u003c/p\\u003e\\u003cp\\u003eFinally, when comparing the ratios of subsidence between expandable and static groups, 3 studies were included, with almost no heterogeneity between the results (I\\u003csup\\u003e2\\u003c/sup\\u003e\\u0026thinsp;=\\u0026thinsp;0%), so a common effects model was used. A significant difference was seen between the groups with an odds ratio of 0.16 ([95% CI\\u0026thinsp;=\\u0026thinsp;0.02; 0.99], z = -12.69, p\\u0026thinsp;=\\u0026thinsp;0.049). (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig5\\\" class=\\\"InternalRef\\\"\\u003e5\\u003c/span\\u003e).\\u003c/p\\u003e\\u003cp\\u003e\\u003c/p\\u003e\"},{\"header\":\"Discussion\",\"content\":\"\\u003cp\\u003eThe use of expandable interbody fusion techniques are increasing in literature, given the potential ability of this dispostives to present a more tailor-made approach for each patient. Unlike static cages, expandable devices allow intraoperative modulation of both disc height and lordotic angle, facilitating precise correction of sagittal alignment at the index level[\\u003cspan citationid=\\\"CR6\\\" class=\\\"CitationRef\\\"\\u003e6\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e].\\u003c/p\\u003e\\u003cp\\u003eComparative studies consistently show that expandable cages exhibit lower subsidence rates than static interbody devices in lateral approaches. In minimally invasive lateral lumbar fusion, the use of height and lordosis adjustable cages was associated with a significant reduction in endplate breach and subsidence events compared to rigid PEEK or titanium implants[\\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e].\\u003c/p\\u003e\\u003cp\\u003eBeyond lordosis correction, expandable cages offer theoretical and demonstrated benefits in indirect decompression by restoring foraminal and canal dimensions without posterior element removal. Clinical radiographic series have shown that expandable spacers significantly increase anterior and posterior disc height as well as neuroforaminal height, translating into relief of radicular symptoms through ligamentotaxis [\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e]. Early data from 2025 further highlight that enhanced segmental lordosis achieved by expandable devices correlates with spontaneous enlargement of spinal canal area, obviating direct decompression in select LLIF and PTP cases[\\u003cspan citationid=\\\"CR17\\\" class=\\\"CitationRef\\\"\\u003e17\\u003c/span\\u003e].\\u003c/p\\u003e\\u003cp\\u003eDespite these advantages, expandable cages introduce unique device-related risks that merit careful consideration. The internal architecture of many expandable designs precludes packing with autologous bone graft, raising theoretical concerns about fusion potential and demanding long‐term outcome data[\\u003cspan citationid=\\\"CR6\\\" class=\\\"CitationRef\\\"\\u003e6\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e]. Moreover, overexpansion can precipitate endplate violation or device failure, causing loss of disc height correction, which might lead to restenosis or loss of lordosis[\\u003cspan citationid=\\\"CR18\\\" class=\\\"CitationRef\\\"\\u003e18\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR19\\\" class=\\\"CitationRef\\\"\\u003e19\\u003c/span\\u003e].\\u003c/p\\u003e\\u003cp\\u003e\\u003cb\\u003eLimitations\\u003c/b\\u003e\\u003c/p\\u003e\\u003cp\\u003eThe present review is not without limitations, with its main two challenges being the small number of studies and the absence of higher quality randomized controlled studies.\\u003c/p\\u003e\"},{\"header\":\"Conclusion\",\"content\":\"\\u003cp\\u003eThe present study presents a updated review of the use of expandable technology in lateral lumbar interbody fusion techniques, showing that this devices might lead to a reduction in the occurrence of subsidence compared to static cages, and to a significant enhancement of segmental lordosis after surgery, however not significantly higher than the static group.\\u003c/p\\u003e\\u003cp\\u003eFuture studies with more patients and higher levels of evidence (such as randomized controlled studies) should be performed so a more precise estimation of the expandable cages effect in segmental lordosis and subsidence reduction can be performed.\\u003c/p\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eFunding:\\u003c/strong\\u003e The authors declare that no funds, grants, or other support were received during the preparation of this manuscript\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eCompeting Interests:\\u003c/strong\\u003e The authors have no relevant financial or non-financial interests to disclose.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAuthor Contributions: \\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eEJ - Manuscript design, writing and revision\\u003c/p\\u003e\\n\\u003cp\\u003eLMCG - Manuscript writing and revision\\u003c/p\\u003e\\n\\u003cp\\u003eISV - Manuscript writing and revision\\u003c/p\\u003e\\n\\u003cp\\u003eGP - Manuscript design, revision, statical analysis and image creation\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eEthics approval:\\u003c/strong\\u003e This is a systematic revision study; therefore, no previous IRB approval was needed.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eClinical trial number\\u003c/strong\\u003e: not applicable.\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\n\\u003cli\\u003eOzgur BM, Aryan HE, Pimenta L, Taylor WR (2006) Extreme Lateral Interbody Fusion (XLIF): a novel surgical technique for anterior lumbar interbody fusion. Spine Journal 6:435\\u0026ndash;443\\u003c/li\\u003e\\n\\u003cli\\u003ePimenta L, Marchi L, Oliveira L, Fortti F, Coutinho E, Jensen R, Amaral R (2017) History and Rationale for the Minimally Invasive Lateral Approach. Lateral Access Minimally Invasive Spine Surgery 3\\u0026ndash;9\\u003c/li\\u003e\\n\\u003cli\\u003eMalham GM, Parker RM, Goss B, Blecher CM (2015) Clinical results and limitations of indirect decompression in spinal stenosis with laterally implanted interbody cages: results from a prospective cohort study. European Spine Journal 24:339\\u0026ndash;345\\u003c/li\\u003e\\n\\u003cli\\u003eLang G, Perrech M, Navarro-Ramirez R, Hussain I, Pennicooke B, Maryam F, Avila MJ, H\\u0026auml;rtl R (2017) Potential and Limitations of Neural Decompression in Extreme Lateral Interbody Fusion\\u0026mdash;A Systematic Review. World Neurosurg 101:99\\u0026ndash;113\\u003c/li\\u003e\\n\\u003cli\\u003eBeyer RS, Shooshani T, Batista B, Fraipont GM, Pooladzandi O, Brown NJ, Pennington Z, Pham MH (2024) Static Versus Expandable Cages in Minimally Invasive Lateral Lumbar Interbody Fusion. Clin Spine Surg. https://doi.org/10.1097/BSD.0000000000001737\\u003c/li\\u003e\\n\\u003cli\\u003eMao Y, Patel AA, Meade S, Benzel E, Steinmetz MP, Mroz T, Habboub G (2024) Review of mechanisms of expandable spine surgery devices. Expert Rev Med Devices 21:381\\u0026ndash;390\\u003c/li\\u003e\\n\\u003cli\\u003eLee S Bin, Yoon J, Park SJ, Chae DS (2024) Expandable Cages for Lumbar Interbody Fusion: A Narrative Review. Journal of Clinical Medicine 2024, Vol 13, Page 2889 13:2889\\u003c/li\\u003e\\n\\u003cli\\u003eHiyama A, Katoh H, Sakai D, Sato M, Watanabe M (2023) Early Radiological Assessment of Static and Expandable Cages in Lateral Single Position for Indirect Decompression- Lateral Lumbar Interbody Fusion. World Neurosurg 178:e453\\u0026ndash;e464\\u003c/li\\u003e\\n\\u003cli\\u003eLi YM, Frisch RF, Huang Z, Towner J, Li YI, Greeley SL, Ledonio C (2020) Comparative Effectiveness of Expandable Versus Static Interbody Spacers via MIS LLIF: A 2-Year Radiographic and Clinical Outcomes Study. Global Spine J 10:998\\u0026ndash;1005\\u003c/li\\u003e\\n\\u003cli\\u003eLi YM, Huang Z, Towner J, Li YI, Riggleman JR, Ledonio C (2021) Expandable Technology Improves Clinical and Radiographic Outcomes of Minimally Invasive Lateral Lumbar Interbody Fusion for Degenerative Disc Disease. Int J Spine Surg 15:87\\u003c/li\\u003e\\n\\u003cli\\u003eMalham GM, Blecher CM, Munday NR, Hamer RP (2022) Expandable Lateral Lumbar Cages With Integrated Fixation: A Viable Option for Rostral Adjacent Segment Disease. Int J Spine Surg 16:748\\u0026ndash;759\\u003c/li\\u003e\\n\\u003cli\\u003eStienen MN, Fischer G, B\\u0026auml;ttig L, Veeravagu A, Martens B (2024) Minimally-invasive lateral thoracic and lumbar interbody fusion (LLIF) with expandable interbody cages \\u0026ndash; Considerations, complications \\u0026amp; outcomes. Brain \\u0026amp; Spine 4:102870\\u003c/li\\u003e\\n\\u003cli\\u003eHiyama A, Sakai D, Katoh H, Sato M, Watanabe M (2025) Segmental Lordosis and Disc Height Discrepancies in Lateral Lumbar Interbody Fusion Using Expandable Cages. Int J Spine Surg 19:188\\u0026ndash;199\\u003c/li\\u003e\\n\\u003cli\\u003eLi YM, Frisch RF, Huang Z, Towner JE, Li YI, Edsall AL, Ledonio C (2021) Comparative Effectiveness of Laterally Placed Expandable versus Static Interbody Spacers: A 1-Year Follow-Up Radiographic and Clinical Outcomes Study. Asian Spine J 15:89\\u0026ndash;96\\u003c/li\\u003e\\n\\u003cli\\u003eFrisch RF, Luna IY, Brooks DM, Joshua G, O\\u0026rsquo;Brien JR (2018) Clinical and radiographic analysis of expandable versus static lateral lumbar interbody fusion devices with two-year follow-up. J Spine Surg 4:62\\u0026ndash;71\\u003c/li\\u003e\\n\\u003cli\\u003eCalvachi-Prieto P, McAvoy MB, Cerecedo-Lopez CD, et al (2021) Expandable Versus Static Cages in Minimally Invasive Lumbar Interbody Fusion: A Systematic Review and Meta-Analysis. World Neurosurg 151:e607\\u0026ndash;e614\\u003c/li\\u003e\\n\\u003cli\\u003eHiyama A, Sakai D, Katoh H, Sato M, Watanabe M (2025) Lumbar Interbody Fusion Using Expandable Cages Segmental Lordosis and Disc Height Discrepancies in Lateral. https://doi.org/10.14444/8726\\u003c/li\\u003e\\n\\u003cli\\u003eKirnaz S, Navarro-Ramirez R, Gu J, et al (2020) Indirect Decompression Failure After Lateral Lumbar Interbody Fusion\\u0026mdash;Reported Failures and Predictive Factors: Systematic Review. Global Spine J 10:8S\\u003c/li\\u003e\\n\\u003cli\\u003eElNemer W, Kim A, Silva-Aponte J, Raad M, Azad T, Durand WM, Hassanzadeh H, Kebaish K, Jain A (2025) An Analysis of the Complication Reports of Expandable Lumbar Interbody Cages in the Food and Drug Administration Manufacturer and User Facility Device Experience Database. Orthopedics 48:e7\\u0026ndash;e14\\u003c/li\\u003e\\n\\u003c/ol\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":true,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":false,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"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\":\"Interbody fusion, Expandable devices, LLIF, Systematic Review, Metanalysis\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-7273973/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-7273973/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003cp\\u003e\\u003cb\\u003ePurpose\\u003c/b\\u003e\\u003c/p\\u003e\\u003cp\\u003eExpandable cages have been introduced in lateral lumbar interbody fusion (LLIF) to enhance segmental lordosis correction and reduce endplate damage and subsidence risk. However, evidence regarding their efficacy remains inconsistent. This systematic review and meta-analysis aimed to evaluate the ability of expandable cages to promote segmental lordosis and assess their safety profile, specifically regarding subsidence and complications, compared to static cages.\\u003c/p\\u003e\\u003cp\\u003e\\u003cb\\u003eMethods\\u003c/b\\u003e\\u003c/p\\u003e\\u003cp\\u003eA systematic search of PubMed, Google Scholar, Ovid, and BVS databases was conducted following PRISMA guidelines. Inclusion criteria were original studies using expandable cages in LLIF, reporting on segmental lordosis and/or subsidence. Quality was assessed using the Newcastle\\u0026ndash;Ottawa Scale. Random-effects meta-analyses with cluster-robust variance estimation and subgroup/meta-regression analyses were performed using R software.\\u003c/p\\u003e\\u003cp\\u003e\\u003cb\\u003eResults\\u003c/b\\u003e\\u003c/p\\u003e\\u003cp\\u003eNine studies with a total of 414 patients (expandable group) were included. The pooled mean segmental lordosis at last follow-up in the expandable cage group was 8.67\\u0026deg; (95% CI: 5.34\\u0026ndash;11.9\\u0026deg;), with no significant influence from preoperative lordosis. When compared to static cages, the mean difference in lordosis was not statistically significant (MD = \\u0026minus;\\u0026thinsp;2.56\\u0026deg;, p\\u0026thinsp;=\\u0026thinsp;0.27). Subsidence rate for expandable cages was 4% (95% CI: 1\\u0026ndash;15%). A significant reduction in odds of subsidence was observed with expandable cages versus static cages (OR\\u0026thinsp;=\\u0026thinsp;0.16; 95% CI: 0.02\\u0026ndash;0.99, p\\u0026thinsp;=\\u0026thinsp;0.049). Overall complication data were inconsistently reported and not pooled.\\u003c/p\\u003e\\u003cp\\u003e\\u003cb\\u003eConclusion\\u003c/b\\u003e\\u003c/p\\u003e\\u003cp\\u003eExpandable cages in LLIF are associated with low subsidence rates and achieve substantial segmental lordosis correction, although superiority over static cages in lordosis gain remains unproven. These findings support their use for individualized anatomic correction; however, more high-quality, prospective studies are needed to validate their clinical advantages and long-term outcomes.\\u003c/p\\u003e\",\"manuscriptTitle\":\"Radiological and Clinical Outcomes of Expansive LLIF cages – Single- arm and comparative systematic revision with metanalysis\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2025-10-12 13:57:17\",\"doi\":\"10.21203/rs.3.rs-7273973/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"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\":\"4e022d5a-c234-49a4-b5cd-03fa25db661e\",\"owner\":[],\"postedDate\":\"October 12th, 2025\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"posted\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2025-11-13T13:08:36+00:00\",\"versionOfRecord\":[],\"versionCreatedAt\":\"2025-10-12 13:57:17\",\"video\":\"\",\"vorDoi\":\"\",\"vorDoiUrl\":\"\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-7273973\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-7273973\",\"identity\":\"rs-7273973\",\"version\":[\"v1\"]},\"buildId\":\"8U1c8b4HqxoKbykW_rLl7\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}