Effect of posterolateral fusion versus posterior lumbar interbody fusion on sagittal radiographic parameters in adult patients with low-grade isthmic spondylolisthesis: a randomized controlled trial

Effect of posterolateral fusion versus posterior lumbar interbody fusion on sagittal radiographic parameters in adult patients with low-grade isthmic spondylolisthesis: a randomized controlled trial | 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 Effect of posterolateral fusion versus posterior lumbar interbody fusion on sagittal radiographic parameters in adult patients with low-grade isthmic spondylolisthesis: a randomized controlled trial Mahmoud Fouad Ibrahim, Fady Samy Saeed, Khaled Mohammed Hassan, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3325681/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: This randomized controlled study aims to specifically investigate and compare the effects of posterolateral fusion (PLF) and posterior lumbar interbody fusion (PLIF) on sagittal radiographic parameters, and to evaluate the correlation between the changes in these parameters and the clinical outcome. Methods: A total of 42 patients with single level low-grade isthmic spondylolisthesis were included in the study. The patients were randomly allocated into 2 groups: PLF group (21 patients) and PLIF (group 21 patients). The mean age was 40.23 ± 10.25 years in the PLF group and 35.81 ± 10.58 in the PLIF group. Of the 42 patients, 13 cases were male and 29 cases were female. All patients had a follow-up period of at least 24 months. Radiographic outcomes included pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), sagittal vertical axis (SVA), T1 pelvic angle (TPA), slip angle (SA), slip degree (SD) and disc height (DH). Clinical outcomes were assessed by Oswestry Disability Index (ODI) and visual analogue scale (VAS). Results: Upon comparing postoperative measurements of both groups, only SA, SD and DH were significantly better in PLIF group. However, when comparing the means of correction (postoperative values- preoperative values), all radiographic parameters were found to be significantly better in PLIF group. Additionally, SA and DH showed significantly less correction loss in the PLIF group. ODI and VAS scores improved significantly in both groups during the final follow-up, with no significant differences between the two groups. Changes in ODI and VAS were significantlycorrelated with changes in SD, DH, and LL. Conclusion: PLIF exhibits greater strength in correcting sagittal radiographic parameters. Nevertheless, this difference does not seem to influence short-term clinical results. Notably, changes in DH, SA, and LL displayed significant correlations with changes in ODI and VAS, underscoring the importance of restoring disc height, rectifying slip angle, and reestablishing normal lumbar lordosis as crucial steps in the surgical management of isthmic spondylolisthesis. Trial registration ClinicalTrials.gov Identifier: NCT03877341, registered on March 15, 2019. isthmic spondylolisthesis postrolateral fusion posterior lumbar interbody fusion sagittal radiographic parameters Figures Figure 1 Figure 2 Figure 3 Introduction Isthmic spondylolisthesis (IS) is a condition in which there is a forward slippage of one vertebra over the one below due to a defect in the pars interarticularis. This condition can lead to spinal instability, resulting in chronic low back pain and disability. The exact cause of isthmic spondylolisthesis is still undetermined; however, abnormal spinopelvic sagittal parameters play an important role not only in the development of isthmic spondylolisthesis but also in its progression [ 4 , 10 , 13 , 17 ]. Posterior lumbar interbody fusion (PLIF) and posterior lumbar fusion (PLF) are commonly performed procedures for the treatment of low-grade single-level isthmic spondylolisthesis, both of which aim to restore spinal stability and alleviate symptoms. However, the optimal surgical technique for this condition is still debated, and the effect of these techniques on spinopelvic parameters remains unclear. Several studies have compared the clinical outcomes and fusion rates between PLF and PLIF [ 5 , 6 , 16 ]. However, few studies have compared the radiographic sagittal parameters after these two techniques and none of them were randomized controlled trials [ 1 , 7 , 19 ]. There is growing evidence suggesting that radiographic sagittal parameters play a significant role in the surgical outcome of spinal fusion procedures. Proper sagittal alignment helps distribute the load across the spinal column and pelvic girdle, reducing the risk of complications such as adjacent segment disease, implant failure, and pseudarthrosis [ 8 , 12 , 20 ]. Therefore, this study is the first randomized controlled trial that aims to compare the sagittal radiographic parameters after PLF and PLIF in patients with single-level low-grade isthmic spondylolisthesis and to study the correlation between the changes in these parameters and the clinical outcome. Patients and Methods This study is a randomized controlled trial, which was carried out at Assiut University Hospital. Between April 2019 and February 2021, 42 adult patients with IS were enrolled in the study. The inclusion criteria included adult patients with low-grade (Meyerding Ι, ΙΙ), single-level isthmic spondylolisthesis who failed to respond to conservative treatment for more than 6 months. Patients with degenerative spondylolisthesis, multiple-level spondylolisthesis, high-grade spondylolisthesis (Meyerding ΙΙΙ, ӀѴ, Ѵ), previous lumbar spine surgery, lumbar scoliosis, or other spinal disorders that could affect the study outcomes were excluded. The original sample size for our study was determined to be 46 participants based on power calculations considering the anticipated effect size, desired level of significance, and statistical power. However, during the course of the study, we experienced a total loss of 4 participants, leading to a final sample size of 42 participants. Of the 4 lost participants, one unfortunate participant passed away due to complications from COVID-19 unrelated to the surgical procedure. The remaining participant could not be reached for follow-up, rendering their data unavailable for analysis. A total of 42 patients were enrolled in the study, with 21 patients in each group. The participants were randomly assigned to one of the two surgical techniques using a computer-generated randomization sequence. The allocation ratio was 1:1 in fixed blocks of 2. The surgeon in charge opened an opaque sealed envelope the day before the surgery and allocated the patient according to the sequence. Patients underwent either PLF or PLIF. Both surgical techniques were performed by experienced spine surgeons following standardized protocols. All patients were followed up for at least 24 months. The study was conducted in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines and was approved by the Institutional Review Board of the Faculty of Medicine at Assiut University (registration number: 17100676). All participants provided written informed consent before enrollment in the study. Data were analyzed using GraphPad Prism for macOS version 9.5.0 (GraphPad Software, San Diego, CA, USA). Continuous data were expressed in the form of mean ± SD while nominal data were expressed in the form of frequency (percentage). Chi²-test was used to compare the nominal data of different groups in the study while the Student t-test was used to compare the mean of different two groups. Paired t-test was used to compare preoperative and follow-up assessments of the same group. The correlation of changes in ODI and VAS with the changes in different parameters was determined by Pearson correlation. The level of confidence was kept at 95%; hence a P-value < 0.05 indicated a significant association. Results Both groups showed no significant difference with regard to patients’ age, gender distribution, level of spondylolisthesis or Meyerding grade. On the other hand, operative time and blood loss were significantly lower in the PLF group (p-values of 0.003 and < 0.0001 respectively) (Table 1 ). Table 1 Clinical data of both groups. PLF (n = 21) PLIF (n = 21) P value Age 40.23 ± 10.25 35.81 ± 10.58 0.52 Gender Male 6 (28.6%) 7 (33.3%) 0.50 Female 15 (71.4%) 14 (66.7%) Level of spondylolisthesis 0.58 L3-4 1 (4.8%) 0 L4-5 6 (28.6%) 8 (38.1%) L5-S1 14 (66.7%) 13 (61.9%) Meyerding grade 0.17 I 13 (61.9%) 12 (57.1%) II 8 (38.1%) 9 (42.9%) Operative time (min) 71.57 ± 6.88 97.14 ± 23.05 < 0.0001 Blood loss (ml) 619.05 ± 218.23 928.57 ± 286.61 0.0003 Data expressed as mean (SD), frequency (percentage). PLF: posterolateral fusion; PLIF: posterior lumbar interbody fusion Preoperatively, no significant difference was found between the radiographic parameters of the PLF and PLIF groups. When comparing preoperative and last follow-up measurements within each group, there was a statistically significant improvement in all spinopelvic parameters (except for PI) in the PLIF group. On the other hand, in the PLF group, only PT, SS, LL, and SD showed a statistically significant improvement. Upon comparing postoperative measurements of both groups, only the deformity parameters (SA, SD and DH) were significantly better in PLIF group. However, when comparing the means of correction (postoperative values- preoperative values), all radiographic parameters (except for PI) were found to be significantly better in PLIF group. Additionally, when comparing the means of correction loss (last follow-up values - postoperative values), only the SA and DH were significantly lower in PLIF group (Tables 2 and 3 ). Table 2 Changes in spinopelvic parameters PLF (n = 21) PLIF (n = 21) P 1 value Pelvic tilt (degree) Preoperative 18.27 ± 5.35 20.13 ± 6.84 0.3331 Post-operative 15.56 ± 4.96 14.55 ± 5.13 0.5223 Follow up after 12 months 15.68 ± 4.59 15.00 ± 5.12 0.6457 Correction value -2.71 ± 3.50 -5.58 ± 4.02 0.0183 Correction loss -0.13 ± 1 .71 -0.44 ± 0.62 0.4410 P 2 value 0.0463 0.0088 Pelvic incidence (degree) Preoperative 57.15 ± 8.30 53.38 ± 8.98 0.1651 Post-operative 57.81 ± 8.71 55.41 ± 7.38 0.3412 Follow up after 12 months 57.87 ± 8.79 55.05 ± 7.48 0.2695 Correction value 0.66 ± 1.41 2.03 ± 7.92 0.4391 Correction loss -0.06 ± 1.01 0.36 ± 0.63 0.1138 P 2 value 0.7879 0.5171 Sacral slope (degree) Preoperative 37.98 ± 4.97 34.99 ± 4.92 0.0570 Post-operative 42.25 ± 5.16 42.52 ± 3.95 0.8492 Follow up after 12 months 41.65 ± 5.57 41.93 ± 3.84 0.8476 Correction value 4.28 ± 2.98 7.54 ± 3.56 0.0025 Correction loss 1.12 ± 1.23 0.59 ± 0.98 0.1253 P 2 value 0.0298 < 0.0001 Lumbar lordosis (degree) Preoperative -54.86 ± 6.52 -49.85 ± 10.09 0.0634 Post-operative -61.17 ± 7.77 -61.23 ± 5.61 0.9765 Follow up after 12 months -59.49 ± 8 .06 -59.69 ± 5 .77 0.9303 Correction value -6.31 ± 6.12 -11.38 ± 8.74 0.0356 Correction loss -1.67 ± 1.19 -1.54 ± 1 .96 0.7983 P 2 value 0.0470 0.0004 T1 pelvic angle (degree) Preoperative 11.39 ± 6.01 15.15 ± 8.59 0.1078 Post-operative 10.27 ± 5.69 8.96 ± 4.73 0.4240 Follow up after 12 months 10.92 ± 5.68 10.06 ± 5.22 0.6134 Correction value -1.12 ± 5.62 -6.19 ± 5.95 0.0071 Correction loss -0.65 ± 2.22 -1.10 ± 2.79 0.5681 P 2 value 0.7952 0.0254 Sagittal vertical axis (degree) Preoperative -10.42 ± 38.39 10.77 ± 34.96 0.0688 Post-operative -2.25 ± 33.15 -8.98 ± 18.15 0.5925 Follow up after 12 months -1.30 ± 36.02 -8.17 ± 16 .00 0.7843 Correction value 8.18 ± 42.68 -19.74 ± 33.38 0.0232 Correction loss -0.95 ± 18.31 -0.81 ± 19 .08 0.9810 P 2 value 0.4318 0.0296 Data expressed as mean (SD). P 1 value compares both groups at different times while P 2 value compares pre-operatives and follow-up measurements in the same group. Table 3 Changes in deformity parameters PLF (n = 21) PLIF (n = 21) P 1 value Slip degree (mm) Preoperative 7.54 ± 4.57 8.20 ± 2.91 0.5790 Post-operative 3.04 ± 2.23 0.58 ± 0.96 < 0.0001 Follow up after 12 months 3.45 ± 2.23 0.90 ± 1.08 < 0.0001 Correction value -4.50 ± 3.68 -7.62 ± 2.38 0.0022 Correction loss -0.40 ± 0.55 -0.32 ± 0.32 0.5386 P 2 value 0.0007 < 0.0001 Slip angle (degree) Preoperative -4.49 ± 6.72 -1.99 ± 7.24 0.2524 Post-operative -8.17 ± 6.49 -11.71 ± 3.68 0.0339 Follow up after 12 months -6.88 ± 6.17 -11.06 ± 3.68 0.0110 Correction value -3.68 ± 3.55 -9.72 ± 5.56 0.0001 Correction loss -1.29 ± 1.08 -0.65 ± 0.46 0.0168 P 2 value 0.2381 < 0.0001 Disc height (mm) Preoperative 7.74 ± 3.59 8.15 ± 4.58 0.7502 Post-operative 8.95 ± 4.18 12.88 ± 3.68 0.0025 Follow up after 12 months 7.97 ± 4.22 12.60 ± 3.50 0.0004 Correction value 1.21 ± 1.06 4.73 ± 1.62 < 0.0001 Correction loss 0.98 ± 1.24 0.28 ± 0.37 0.0178 P 2 value 0.8528 0.0010 Data expressed as mean (SD). P 1 value compares both groups at different times while P 2 value compares pre-operatives and follow-up measurements at the same group Regarding the ODI and VAS, both groups exhibited significant improvements in these measures at the last follow-up in comparison to their preoperative evaluations. However, when comparing the two groups, there were no significant differences in ODI and VAS scores either preoperatively or at the last follow-up (Table 4 ). In the PLIF group, there was a significant positive correlation between the changes in PT, SS, LL, SVA, and TPA with the changes in SA and DH. On the other hand, within the PLF group, the changes in SA and DH exhibited a significant positive correlation only with the changes in LL, SVA, and TPA (Table 5 ). In both groups, changes in ODI and VAS showed significant positive correlations with changes in SA, DH and LL. However, there were no significant correlations between changes in ODI and VAS with changes in PT, PI, SS, TPA, SVA or SD (Table 6 ). Table 4 Changes in clinical parameters PLF (n = 21) PLIF (n = 21) P 1 value ODI Preoperative 44.76 ± 16.22 46.10 ± 9.70 0.7469 Follow up after 12 months 17.62 ± 8.98 18.00 ± 10.2 0.8968 Correction value 27.14 ± 6.47 28.10 ± 7.89 0.671 P 2 value < 0.0001 <0.0001 VAS Preoperative 5.34 ± 1.81 5.73 ± 2.38 0.5534 Follow up after 12 months 2.29 ± 1.44 2.39 ± 2.55 0.8794 Correction value 3.05 ± 1.43 3.33 ± 1.11 0.4740 P 2 value <0.0001 <0.0001 Data expressed as mean (SD). P 1 value compares both groups at different times while P 2 value compares pre-operatives and follow-up measurements in the same group. VAS, visual analogue scale; ODI, Oswestry Disability Index Table 5 Correlation between changes in spinopelvic parameters and deformity parameters. SD SA HOD PLF PLIF PLF PLIF PLF PLIF r P value r P value r P value r P value r P value r P value PT 0.4022 0.0707 0.2393 0.2961 0.1810 0.4324 0.5051 0.0195 0.2309 0.3139 0.5391 0.0117 SS -0.1896 0.4105 0.0309 0.8943 0.2249 0.3270 0.4809 0.0273 0.2076 0.3666 0.5392 0.0116 LL -0.0175 0.9401 -0.0143 0.9509 0.5393 0.0116 0.4890 0.0245 0.6658 0.0010 0.5074 0.0189 TPA 0.4084 0.0660 0.2012 0.3819 0.5188 0.0160 0.7287 0.0002 0.4682 0.0323 0.6224 0.0026 SVA 0.3125 0.1679 0.0408 0.8607 0.4704 0.0314 0.5032 0.0201 0.4111 0.0441 0.4348 0.0388 Data expressed as r-value (strength of correlation), and P-value (significance of correlation). PT, Pelvic tilt; SS, sacral slope; LL, Lumbar lordosis; TPA, T1 pelvic angle; SVA, Sagittal vertical axis; SD, Slip degree; SA, Slip angle; DH, Disc height. Table 6 Correlation between changes in clinical outcomes and changes in radiographic parameters VAS ODI PLF PLIF PLF PLIF r P value r P value r P value r P value PT -0.2337 0.3078 0.3097 0.1719 0.0961 0.6786 0.3380 0.1340 SS 0.1729 0.4537 0.4132 0.0626 0.2446 0.2852 0.3654 0.1033 LL 0.6275 0.0023 0.4875 0.0250 0.5874 0.0051 0.4707 0.0313 TPA 0.0005 0.9984 0.2735 0.2302 0.2809 0.2175 0.3250 0.1506 SVA 0.1866 0.4180 0.1485 0.5206 0.2434 0.2876 0.0891 0.7010 SD -0.1974 0.3910 -0.1430 0.5364 0.1852 0.4215 0.0494 0.8317 SA 0.4663 0.0331 0.5394 0.0116 0.4916 0.0236 0.5273 0.0140 DH 0.5796 0.0059 0.5881 0.0050 0.6649 0.0010 0.6570 0.0012 Data expressed as r-value (strength of correlation), and P-value (significance of correlation). VAS, visual analogue scale; ODI, Oswestry Disability Index; PT, Pelvic tilt; SS, sacral slope; LL, Lumbar lordosis; TPA, T1 pelvic angle; SVA, Sagittal vertical axis; SD, Slip degree; SA, Slip angle; DH, Disc height. Discussion There have been many reports comparing PLF and PLIF for treating isthmic spondylolisthesis, with a focus on their fusion rates and clinical outcomes, either alone or in combination [ 5 , 6 , 16 ]. However, only a few reports have explored the comparison between the two techniques in terms of their effect on sagittal radiographic parameters or their clinical correlation [ 1 , 7 , 19 ]. In this study, we evaluated changes in sagittal radiographic parameters and their their correlation with clinical outcomes as assessed by VAS score and Oswestry disability index (ODI). In the nonrandomised controlled prospective study of Feng et al. [ 7 ], they evaluated the effect of PLF and PLIF on spinopelvic sagittal balance in a patient with low-grade isthmic spondylolisthesis. Both procedures could reduce the PT and increase the SS postoperatively, with no significant differences. The LL increased in the PLIF group but decreased in the PLF group. The SD improved significantly in both groups. The DH of the PLIF group showed a significant increase postoperatively,while the postoperative DH of the PLF group showed no significant difference from the preoperative value. The SA increased significantly after the operation in the PLIF group while in the PLF group, without the cage, the SA decreased. In the current study, significant improvement in all spinopelvic parameters (except for PI) was observed within the PLIF group when comparing measurements taken preoperatively and at the latest follow-up. In the PLF group, only PT, SS and LL exhibited a statistically significant improvement between preoperative and latest follow-up measurements. Both procedures have the capacity to restore the physiological status of local spinopelvic parameters (PT, SS and LL). The improvement of these parameters has been shown to be correlated with positive clinical outcomes [ 3 , 18 ], which could explain the similar short term clinical outcomes observed in both groups. Regarding the deformity parameters, within the PLIF group, there was a statistically significant improvement in SA, SD, and DH from the preoperative to the latest follow-up measurements. On the other hand, in the PLF group, only SD showed a statistically significant improvement. When comparing postoperative measurements of both groups, only the deformity parameters (SA, SD and DH) were significantly better in PLIF group. This is mainly due to the great ability of PLIF to reduce slippage, correct kyphosis and restore disc height. However, when comparing the means of correction (postoperative values- preoperative values), all radiographic parameters (except for PI) were found to be significantly better in PLIF group. Comparing the postoperative measurements may not capture the full picture of the intervention's effectiveness, while the change score approach provides a more comprehensive understanding of the impact of the treatment on the participants' outcomes. Therefore, PLIF is more powerful than PLF in correcting both spinopelvic and deformity parameters. Additionally, when comparing the means of correction loss (last follow up values- postoperative values), only the SA and DH were significantly lower in PLIF group. This could be explained by the use of cages in the PLIF group, which maintains the achieved correction. In the context of exploring the correlation between changes in spinopelvic parameters and deformity parameters, several noteworthy findings have emerged from previous research. Park et al. [ 19 ] reported that the changes in DH showed a significant positive correlation with the changes in LL and SVA, while the changes in SD and SA showed no correlation with changes in spinopelvic parameters. In a separate study, Feng et al. [ 7 ] reported that the changes in SD and DH had a significant positive correlation with the changes in LL in the PLIF group, while in the PLF group, only the changes in SD had a significant negative correlation with the changes in LL. Moreover, Kawakami et al. [ 11 ] reported that the decrease in SD, the increase in LL, and subsequent restoration of sagittal alignment improved clinical outcomes in patients undergoing posterolateral fusion for the treatment of degenerative spondylolisthesis. Boachie-Adjei et al. [ 2 ] performed partial lumbosacral kyphosis reduction in patients with high-grade spondylolisthesis. They suggested that the partial reduction in the SA, not the SD, was more important in restoring sagittal balance and a better biomechanical environment for fusion. Furthermore, Godde et al. [ 9 ] reported that restoration of segmental lordosis and LL using a wedge-shaped cage should be performed for restoring sagittal alignment. In our study, the changes in SA and DH showed a significant positive correlation with the changes in PT, SS, LL, SVA and TPA in the PLIF group while in the PLF group, changes in SA and DH showed significant positive correlation with only the changes in LL, SVA and TPA. This emphasizes the importance of restoration of DH and SA for better correction of both local and global sagittal parameters. On the other hand, complete reduction as measured by SD is not as important as restoration of DH and SA. These results are consistent with those from Boachie-Adjei et al. and Godde et al studies [ 2 , 9 ]. Regarding the clinical outcome and the correlation between changes in clinical outcomes and changes in radiographic parameters, two separate prospective studies conducted by Ekman et al. [ 5 ] and Musluman et al. [ 16 ] to compare the clinical outcome after PLIF and PLF for the treatment of ischemic spondylolisthesis. Both studies found no significant difference in the clinical outcome between the two procedures as measured by ODI and VAS. These findings were also supported by a meta-analysis conducted by Luo et al. [ 15 ], who stated that there was no significant difference in the global assessment of clinical outcomes between the two fusion procedures. Farrokhi et al. [ 6 ] described a significantly better improvement in ODI for patients treated with PLF than those who underwent PLIF for IS. In a recent study conducted by Behzadnia et al. [ 1 ], the authors reported significant improvement in VAS after both procedures; however, this improvement was significantly higher in the PLIF group. They also found a significant positive correlation between the changes in VAS and changes in PT. In the present study, both ODI and VAS improved significantly at the last follow up with no significant difference between PLIF and PLF. Additionally, in both groups, changes in ODI and VAS showed a significant positive correlation with changes in SA, DH and LL. Limitations The global disruption caused by the COVID-19 pandemic has had a profound impact on regular healthcare access, leading to challenges in enrolling participants and maintaining regular follow-up and consequently impeding comprehensive data collection. This disruption serves as the root cause behind the primary limitations of this study: the relatively small study population and the short follow-up duration. Therefore, multicenter studies with larger participant numbers and extended follow-up periods should be conducted to thoroughly examine the effect of postoperative radiographic parameters correction on long-term clinical outcomes. Conclusion PLIF exhibits greater efficacy than PLF in correcting sagittal radiographic parameters. However, this disparity does not appear to impact short-term clinical outcomes. It is essential to emphasize that further studies involving extended follow-up periods are necessary to ascertain whether this distinction will influence long-term clinical results. In both groups, changes in DH, SA and LL correlated significantly with changes in ODI and VAS; thus, restoration of disc height, correction of the slip angle and reestablishment of normal lumbar lordosis are the most important steps in surgical treatment of IS. Abbreviations PLF Posterolateral fusion PLIF Posterior lumbar interbody fusion PI Pelvic incidence PT Pelvic tilt SS Sacral slope LL Lumbar lordosis SVA Sagittal vertical axis TPA T1 pelvic angle SA Slip angle SD Slip degree DH Disc height ODI Oswestry Disability Index VAS Visual analogue scale Declarations Ethics approval and consent to participate The study was conducted in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines. The ethical committee of the Faculty of Medicine at Assiut University approved the study (IRB No.: 17100676). This study was registered in ClinicalTrials.gov Identifier: NCT03877341. All participants provided written informed consent before enrollment in the study. Consent for publication All patients provided a consent to use their radiographs for this research. Competing interests All authors declare no competing interests. Authors' contributions MGH and KMH conceived and designed the study. MFI, EME performed the surgeries. MFI, EME, and FSS conducted the measurements, collected, and analysed the data. All authors reviewed the manuscript. MFI and EME drafted the manuscript and designed the figures and tables. Funding No funding or grants are associated with this study. Availability of data and materials The data associated with the paper are not publicly available but are available from the corresponding author on reasonable request. References Behzadnia H, Yousefzadeh- Chabok S, Alijani B, Golmohammadi S, Reyhanian Z, Naseri A, et al. (2020) Spinopelvic parameters and pain in patients with low-grade spondylolisthesis. Romanian Journal of Neurology 19:275-279 Boachie-Adjei O, Do T, Rawlins BA (2002) Partial lumbosacral kyphosis reduction, decompression, and posterior lumbosacral transfixation in high-grade isthmic spondylolisthesis: clinical and radiographic results in six patients. Spine (Phila Pa 1976) 27:E161-168 Bourghli A, Aunoble S, Reebye O, Le Huec JC (2011) Correlation of clinical outcome and spinopelvic sagittal alignment after surgical treatment of low-grade isthmic spondylolisthesis. Eur Spine J 20 Suppl 5:663-668 Curylo LJ, Edwards C, DeWald RW (2002) Radiographic markers in spondyloptosis: implications for spondylolisthesis progression. Spine (Phila Pa 1976) 27:2021-2025 Ekman P, Möller H, Tullberg T, Neumann P, Hedlund R (2007) Posterior lumbar interbody fusion versus posterolateral fusion in adult isthmic spondylolisthesis. Spine (Phila Pa 1976) 32:2178-2183 Farrokhi MR, Rahmanian A, Masoudi MS (2012) Posterolateral versus posterior interbody fusion in isthmic spondylolisthesis. J Neurotrauma 29:1567-1573 Feng Y, Chen L, Gu Y, Zhang ZM, Yang HL, Tang TS (2015) Restoration of the spinopelvic sagittal balance in isthmic spondylolisthesis: posterior lumbar interbody fusion may be better than posterolateral fusion. Spine J 15:1527-1535 Glassman SD, Bridwell K, Dimar JR, Horton W, Berven S, Schwab F (2005) The impact of positive sagittal balance in adult spinal deformity. Spine (Phila Pa 1976) 30:2024-2029 Gödde S, Fritsch E, Dienst M, Kohn D (2003) Influence of cage geometry on sagittal alignment in instrumented posterior lumbar interbody fusion. Spine (Phila Pa 1976) 28:1693-1699 Hanson DS, Bridwell KH, Rhee JM, Lenke LG (2002) Correlation of pelvic incidence with low- and high-grade isthmic spondylolisthesis. Spine (Phila Pa 1976) 27:2026-2029 Kawakami M, Tamaki T, Ando M, Yamada H, Hashizume H, Yoshida M (2002) Lumbar sagittal balance influences the clinical outcome after decompression and posterolateral spinal fusion for degenerative lumbar spondylolisthesis. Spine (Phila Pa 1976) 27:59-64 Kim MK, Lee S-H, Kim E-S, Eoh W, Chung S-S, Lee C-S (2011) The impact of sagittal balance on clinical results after posterior interbody fusion for patients with degenerative spondylolisthesis: A Pilot study. BMC Musculoskeletal Disorders 12:69 Labelle H, Roussouly P, Berthonnaud E, Transfeldt E, O'Brien M, Chopin D, et al. (2004) Spondylolisthesis, pelvic incidence, and spinopelvic balance: a correlation study. Spine (Phila Pa 1976) 29:2049-2054 Lafage R, Ferrero E, Henry JK, Challier V, Diebo B, Liabaud B, et al. (2015) Validation of a new computer-assisted tool to measure spino-pelvic parameters. The Spine Journal 15:2493-2502 Luo J, Cao K, Yu T, Li L, Huang S, Gong M, et al. (2017) Comparison of Posterior Lumbar Interbody Fusion Versus Posterolateral Fusion for the Treatment of Isthmic Spondylolisthesis. Clin Spine Surg 30:E915-e922 Müslüman AM, Yılmaz A, Cansever T, Cavuşoğlu H, Colak I, Genç HA, et al. (2011) Posterior lumbar interbody fusion versus posterolateral fusion with instrumentation in the treatment of low-grade isthmic spondylolisthesis: midterm clinical outcomes. J Neurosurg Spine 14:488-496 Oh SK, Chung SS, Lee CS (2009) Correlation of pelvic parameters with isthmic spondylolisthesis. Asian Spine J 3:21-26 Oikonomidis S, Meyer C, Scheyerer MJ, Grevenstein D, Eysel P, Bredow J (2020) Lumbar spinal fusion of low-grade degenerative spondylolisthesis (Meyerding grade I and II): Do reduction and correction of the radiological sagittal parameters correlate with better clinical outcome? Arch Orthop Trauma Surg 140:1155-1162 Park SJ, Lee CS, Chung SS, Kang KC, Shin SK (2011) Postoperative changes in pelvic parameters and sagittal balance in adult isthmic spondylolisthesis. Neurosurgery 68:355-363; discussion 362-353 Schwab FJ, Blondel B, Bess S, Hostin R, Shaffrey CI, Smith JS, et al. (2013) Radiographical spinopelvic parameters and disability in the setting of adult spinal deformity: a prospective multicenter analysis. Spine (Phila Pa 1976) 38:E803-812 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. 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-3325681","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":231203160,"identity":"8ee98945-cb27-4c74-b89a-9961c3e87bfa","order_by":0,"name":"Mahmoud Fouad Ibrahim","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA5klEQVRIiWNgGAWjYDAC5oNtQPIADwN7A5jP2EBQC1siVAvPAaK1JLCBtDAwSCQQqUW3jbntcUXNHRndmY+fSRcw2MhuOMB8+AU+LWbHGNsNzxx7xmN2O81MegZDmvGGA2xpFni13G9sk2xgOwzUkmAmzcNwOHHDAR4zAwK2ALX8A2q5efwbUMt/oBb+b4S1NLYBtdzgAdlyAGQL8wOCfmnsA2o5k1NszWOQbDzzMJsZPh1ALezPHjZ8O2xvdvz4xts8FXayfcebH3/AqwcVgDzBzMAmQYIWCGAmxZZRMApGwSgY/gAA/RBOTRiTg+oAAAAASUVORK5CYII=","orcid":"","institution":"Orthopedic and Traumatology Department, Assiut University Hospital, Assiut","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Mahmoud","middleName":"Fouad","lastName":"Ibrahim","suffix":""},{"id":231203161,"identity":"7094ddc5-e2b8-461b-85d4-5106c57344be","order_by":1,"name":"Fady Samy Saeed","email":"","orcid":"","institution":"Orthopedic and Traumatology Department, Assiut University Hospital, Assiut","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Fady","middleName":"Samy","lastName":"Saeed","suffix":""},{"id":231203162,"identity":"4241de48-a8c7-47f5-8bfd-41a048ce8ec0","order_by":2,"name":"Khaled Mohammed Hassan","email":"","orcid":"","institution":"Orthopedic and Traumatology Department, Assiut University Hospital, Assiut","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Khaled","middleName":"Mohammed","lastName":"Hassan","suffix":""},{"id":231203163,"identity":"ce3a8961-b1ad-4569-8f41-ae4bd9ab7877","order_by":3,"name":"Mohamed Gamal Hassan","email":"","orcid":"","institution":"Orthopedic and Traumatology Department, Assiut University Hospital, Assiut","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Mohamed","middleName":"Gamal","lastName":"Hassan","suffix":""},{"id":231203164,"identity":"eb2d8502-9e05-457a-b110-53734ec61e9e","order_by":4,"name":"Essam Mohammed El-Morshidy","email":"","orcid":"","institution":"Orthopedic and Traumatology Department, Assiut University Hospital, Assiut","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Essam","middleName":"Mohammed","lastName":"El-Morshidy","suffix":""}],"badges":[],"createdAt":"2023-09-04 22:29:14","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3325681/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3325681/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":42863536,"identity":"510ac798-ba60-41b8-8f0e-baea192323a5","added_by":"auto","created_at":"2023-09-09 01:45:25","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":171392,"visible":true,"origin":"","legend":"\u003cp\u003eDeformity parameters in isthmic spondylolisthesis. (A) Slip degree, (B) Slip angle, (C) Disc height (a + b/2)\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-3325681/v1/167263e9fba42e71f7857ef5.png"},{"id":42863537,"identity":"60407bf1-a99e-42c5-b914-7ee0e75e2385","added_by":"auto","created_at":"2023-09-09 01:45:25","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1384494,"visible":true,"origin":"","legend":"\u003cp\u003eA 35–year-old man with isthmic spondylolisthesis L5-S1. (A) Preoperative lateral radiograph. (B) Immediate postoperative lateral radiograph after PLF L5-S1 (C) Lateral radiograph at the latest follow up\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-3325681/v1/4937b37e4b5ceb751c3923f4.png"},{"id":42864224,"identity":"aeb6f2c6-ba04-4e73-96f6-da27702eb833","added_by":"auto","created_at":"2023-09-09 01:53:25","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":981420,"visible":true,"origin":"","legend":"\u003cp\u003eA 27–year-old man with isthmic spondylolisthesis L5-S1 (A) Preoperative lateral radiograph. (B) Immediate postoperative lateral radiograph after PLIF L5-S1 (C) Lateral radiograph at the latest follow up.\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-3325681/v1/5d1a4dcb379d2391b3925e3a.png"},{"id":45396616,"identity":"dd22b859-f9fc-40db-95b6-9216e2fd2581","added_by":"auto","created_at":"2023-10-29 08:37:29","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2157433,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3325681/v1/66c7e2e8-775a-4fa6-bc0c-15b1222db580.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Effect of posterolateral fusion versus posterior lumbar interbody fusion on sagittal radiographic parameters in adult patients with low-grade isthmic spondylolisthesis: a randomized controlled trial","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIsthmic spondylolisthesis (IS) is a condition in which there is a forward slippage of one vertebra over the one below due to a defect in the pars interarticularis. This condition can lead to spinal instability, resulting in chronic low back pain and disability. The exact cause of isthmic spondylolisthesis is still undetermined; however, abnormal spinopelvic sagittal parameters play an important role not only in the development of isthmic spondylolisthesis but also in its progression [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e \u003cp\u003ePosterior lumbar interbody fusion (PLIF) and posterior lumbar fusion (PLF) are commonly performed procedures for the treatment of low-grade single-level isthmic spondylolisthesis, both of which aim to restore spinal stability and alleviate symptoms. However, the optimal surgical technique for this condition is still debated, and the effect of these techniques on spinopelvic parameters remains unclear.\u003c/p\u003e \u003cp\u003eSeveral studies have compared the clinical outcomes and fusion rates between PLF and PLIF [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. However, few studies have compared the radiographic sagittal parameters after these two techniques and none of them were randomized controlled trials [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. There is growing evidence suggesting that radiographic sagittal parameters play a significant role in the surgical outcome of spinal fusion procedures. Proper sagittal alignment helps distribute the load across the spinal column and pelvic girdle, reducing the risk of complications such as adjacent segment disease, implant failure, and pseudarthrosis [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Therefore, this study is the first randomized controlled trial that aims to compare the sagittal radiographic parameters after PLF and PLIF in patients with single-level low-grade isthmic spondylolisthesis and to study the correlation between the changes in these parameters and the clinical outcome.\u003c/p\u003e"},{"header":"Patients and Methods","content":"\u003cp\u003eThis study is a randomized controlled trial, which was carried out at Assiut University Hospital. Between April 2019 and February 2021, 42 adult patients with IS were enrolled in the study. The inclusion criteria included adult patients with low-grade (Meyerding \u0026Iota;, \u0026Iota;\u0026Iota;), single-level isthmic spondylolisthesis who failed to respond to conservative treatment for more than 6 months. Patients with degenerative spondylolisthesis, multiple-level spondylolisthesis, high-grade spondylolisthesis (Meyerding \u0026Iota;\u0026Iota;\u0026Iota;, ӀѴ, Ѵ), previous lumbar spine surgery, lumbar scoliosis, or other spinal disorders that could affect the study outcomes were excluded.\u003c/p\u003e\n\u003cp\u003eThe original sample size for our study was determined to be 46 participants based on power calculations considering the anticipated effect size, desired level of significance, and statistical power. However, during the course of the study, we experienced a total loss of 4 participants, leading to a final sample size of 42 participants. Of the 4 lost participants, one unfortunate participant passed away due to complications from COVID-19 unrelated to the surgical procedure. The remaining participant could not be reached for follow-up, rendering their data unavailable for analysis. A total of 42 patients were enrolled in the study, with 21 patients in each group. The participants were randomly assigned to one of the two surgical techniques using a computer-generated randomization sequence. The allocation ratio was 1:1 in fixed blocks of 2. The surgeon in charge opened an opaque sealed envelope the day before the surgery and allocated the patient according to the sequence.\u003c/p\u003e\n\u003cp\u003ePatients underwent either PLF or PLIF. Both surgical techniques were performed by experienced spine surgeons following standardized protocols. All patients were followed up for at least 24 months.\u003c/p\u003e\n\u003cp\u003eThe study was conducted in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines and was approved by the Institutional Review Board of the Faculty of Medicine at Assiut University (registration number: 17100676). All participants provided written informed consent before enrollment in the study.\u003c/p\u003e\n\u003cp\u003eData were analyzed using GraphPad Prism for macOS version 9.5.0 (GraphPad Software, San Diego, CA, USA). Continuous data were expressed in the form of mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD while nominal data were expressed in the form of frequency (percentage). Chi\u0026sup2;-test was used to compare the nominal data of different groups in the study while the Student t-test was used to compare the mean of different two groups. Paired t-test was used to compare preoperative and follow-up assessments of the same group. The correlation of changes in ODI and VAS with the changes in different parameters was determined by Pearson correlation. The level of confidence was kept at 95%; hence a P-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 indicated a significant association.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eBoth groups showed no significant difference with regard to patients\u0026rsquo; age, gender distribution, level of spondylolisthesis or Meyerding grade. On the other hand, operative time and blood loss were significantly lower in the PLF group (p-values of 0.003 and \u0026lt;\u0026thinsp;0.0001 respectively) (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u0026nbsp;\u003c/p\u003e\n\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003e\u003cem\u003eClinical data of both groups.\u003c/em\u003e\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePLF (n\u0026thinsp;=\u0026thinsp;21)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePLIF (n\u0026thinsp;=\u0026thinsp;21)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e40.23\u0026thinsp;\u0026plusmn;\u0026thinsp;10.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e35.81\u0026thinsp;\u0026plusmn;\u0026thinsp;10.58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eGender\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6 (28.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7 (33.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15 (71.4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14 (66.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eLevel of spondylolisthesis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.58\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eL3-4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (4.8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eL4-5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6 (28.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8 (38.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eL5-S1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14 (66.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13 (61.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMeyerding grade\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.17\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13 (61.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12 (57.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eII\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8 (38.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9 (42.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOperative time (min)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e71.57\u0026thinsp;\u0026plusmn;\u0026thinsp;6.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e97.14\u0026thinsp;\u0026plusmn;\u0026thinsp;23.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eBlood loss (ml)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e619.05\u0026thinsp;\u0026plusmn;\u0026thinsp;218.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e928.57\u0026thinsp;\u0026plusmn;\u0026thinsp;286.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.0003\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData expressed as mean (SD), frequency (percentage). PLF: posterolateral fusion; PLIF: posterior lumbar interbody fusion\u003c/p\u003e\n\u003cp\u003ePreoperatively, no significant difference was found between the radiographic parameters of the PLF and PLIF groups. When comparing preoperative and last follow-up measurements within each group, there was a statistically significant improvement in all spinopelvic parameters (except for PI) in the PLIF group. On the other hand, in the PLF group, only PT, SS, LL, and SD showed a statistically significant improvement. Upon comparing postoperative measurements of both groups, only the deformity parameters (SA, SD and DH) were significantly better in PLIF group. However, when comparing the means of correction (postoperative values- preoperative values), all radiographic parameters (except for PI) were found to be significantly better in PLIF group. Additionally, when comparing the means of correction loss (last follow-up values - postoperative values), only the SA and DH were significantly lower in PLIF group (Tables \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e and \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e).\u0026nbsp;\u003c/p\u003e\n\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003e\u003cem\u003eChanges in spinopelvic parameters\u003c/em\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePLF (n\u0026thinsp;=\u0026thinsp;21)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePLIF (n\u0026thinsp;=\u0026thinsp;21)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e1 value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePelvic tilt (degree)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e18.27\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;5.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20.13\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;6.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3331\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15.56\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;4.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14.55\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;5.13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5223\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow up after 12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15.68\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;4.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15.00\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;5.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.6457\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-2.71\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;3.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-5.58\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;4.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0183\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.13\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u0026thinsp;1\u003c/strong\u003e.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.44\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;0.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4410\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2 value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0463\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0088\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ePelvic incidence (degree)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e57.15\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;8.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e53.38\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;8.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1651\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e57.81\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;8.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e55.41\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;7.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3412\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow up after 12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e57.87\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;8.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e55.05\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;7.48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2695\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.66\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;1.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.03\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;7.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4391\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.06\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.36\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;0.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1138\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2 value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.7879\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.5171\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSacral slope (degree)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e37.98\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;4.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e34.99\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;4.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0570\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e42.25\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;5.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e42.52\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;3.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8492\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow up after 12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e41.65\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u0026thinsp;5.57\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e41.93\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;3.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8476\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.28\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;2.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.54\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;3.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0025\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.12\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;1.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.59\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;0.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1253\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2 value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0298\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;\u0026thinsp;0.0001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eLumbar lordosis (degree)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-54.86\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;6.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-49.85\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;10.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0634\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-61.17\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;7.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-61.23\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;5.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.9765\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow up after 12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-59.49\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u0026thinsp;8\u003c/strong\u003e.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-59.69\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u0026thinsp;5\u003c/strong\u003e.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.9303\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-6.31\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;6.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-11.38\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;8.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0356\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1.67\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u0026thinsp;1.19\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1.54\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u0026thinsp;1\u003c/strong\u003e.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.7983\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2 value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0470\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0004\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eT1 pelvic angle (degree)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11.39\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;6.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15.15\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;8.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1078\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.27\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;5.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8.96\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;4.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4240\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow up after 12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.92\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;5.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.06\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;5.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.6134\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1.12\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;5.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-6.19\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;5.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0071\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.65\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;2.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1.10\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;2.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5681\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2 value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.7952\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0254\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSagittal vertical axis (degree)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-10.42\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;38.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.77\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;34.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0688\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-2.25\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;33.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-8.98\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;18.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5925\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow up after 12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1.30\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;36.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-8.17\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u0026thinsp;16\u003c/strong\u003e.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.7843\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8.18\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;42.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-19.74\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;33.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0232\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.95\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;18.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.81\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u0026thinsp;19\u003c/strong\u003e.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.9810\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2 value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.4318\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0296\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData expressed as mean (SD). \u003cem\u003eP\u003c/em\u003e1 value compares both groups at different times while \u003cem\u003eP\u003c/em\u003e 2 value compares pre-operatives and follow-up measurements in the same group.\u0026nbsp;\u003c/p\u003e\n\u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003e\u003cem\u003eChanges in deformity parameters\u003c/em\u003e\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePLF (n\u0026thinsp;=\u0026thinsp;21)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePLIF (n\u0026thinsp;=\u0026thinsp;21)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e1 value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSlip degree (mm)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.54\u0026thinsp;\u0026plusmn;\u0026thinsp;4.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8.20\u0026thinsp;\u0026plusmn;\u0026thinsp;2.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5790\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.04\u0026thinsp;\u0026plusmn;\u0026thinsp;2.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;\u0026thinsp;0.0001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow up after 12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.45\u0026thinsp;\u0026plusmn;\u0026thinsp;2.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.90\u0026thinsp;\u0026plusmn;\u0026thinsp;1.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;\u0026thinsp;0.0001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-4.50\u0026thinsp;\u0026plusmn;\u0026thinsp;3.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-7.62\u0026thinsp;\u0026plusmn;\u0026thinsp;2.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0022\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.32\u0026thinsp;\u0026plusmn;\u0026thinsp;0.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5386\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2 value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0007\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;\u0026thinsp;0.0001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSlip angle (degree)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-4.49\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;6.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1.99\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;7.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2524\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-8.17\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;6.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-11.71\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;3.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0339\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow up after 12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-6.88\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;6.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-11.06\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;3.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0110\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-3.68\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;3.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-9.72\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;5.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-1.29\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;1.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-0.65\u0026thinsp;\u003cstrong\u003e\u0026plusmn;\u003c/strong\u003e\u0026thinsp;0.46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0168\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2 value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.2381\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;\u0026thinsp;0.0001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eDisc height (mm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.74\u0026thinsp;\u0026plusmn;\u0026thinsp;3.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8.15\u0026thinsp;\u0026plusmn;\u0026thinsp;4.58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.7502\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8.95\u0026thinsp;\u0026plusmn;\u0026thinsp;4.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.88\u0026thinsp;\u0026plusmn;\u0026thinsp;3.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0025\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow up after 12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.97\u0026thinsp;\u0026plusmn;\u0026thinsp;4.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.60\u0026thinsp;\u0026plusmn;\u0026thinsp;3.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0004\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.21\u0026thinsp;\u0026plusmn;\u0026thinsp;1.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.73\u0026thinsp;\u0026plusmn;\u0026thinsp;1.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;\u0026thinsp;0.0001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection loss\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.98\u0026thinsp;\u0026plusmn;\u0026thinsp;1.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0178\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2 value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.8528\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0010\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData expressed as mean (SD). \u003cem\u003eP\u003c/em\u003e1 value compares both groups at different times while \u003cem\u003eP\u003c/em\u003e 2 value compares pre-operatives and follow-up measurements at the same group\u003c/p\u003e\n\u003cp\u003eRegarding the ODI and VAS, both groups exhibited significant improvements in these measures at the last follow-up in comparison to their preoperative evaluations. However, when comparing the two groups, there were no significant differences in ODI and VAS scores either preoperatively or at the last follow-up (Table \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eIn the PLIF group, there was a significant positive correlation between the changes in PT, SS, LL, SVA, and TPA with the changes in SA and DH. On the other hand, within the PLF group, the changes in SA and DH exhibited a significant positive correlation only with the changes in LL, SVA, and TPA (Table \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e). In both groups, changes in ODI and VAS showed significant positive correlations with changes in SA, DH and LL. However, there were no significant correlations between changes in ODI and VAS with changes in PT, PI, SS, TPA, SVA or SD (Table \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e\n\u003ctable id=\"Tab6\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eChanges in clinical parameters\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePLF (n\u0026thinsp;=\u0026thinsp;21)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePLIF (n\u0026thinsp;=\u0026thinsp;21)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e1 value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eODI\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e44.76\u0026thinsp;\u0026plusmn;\u0026thinsp;16.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e46.10\u0026thinsp;\u0026plusmn;\u0026thinsp;9.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.7469\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow up after 12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.62\u0026thinsp;\u0026plusmn;\u0026thinsp;8.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e18.00\u0026thinsp;\u0026plusmn;\u0026thinsp;10.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8968\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27.14\u0026thinsp;\u0026plusmn;\u0026thinsp;6.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e28.10\u0026thinsp;\u0026plusmn;\u0026thinsp;7.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.671\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2 value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;\u0026thinsp;0.0001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;0.0001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eVAS\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePreoperative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.34\u0026thinsp;\u0026plusmn;\u0026thinsp;1.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.73\u0026thinsp;\u0026plusmn;\u0026thinsp;2.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5534\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFollow up after 12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.29\u0026thinsp;\u0026plusmn;\u0026thinsp;1.44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.39\u0026thinsp;\u0026plusmn;\u0026thinsp;2.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8794\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCorrection value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.05\u0026thinsp;\u0026plusmn;\u0026thinsp;1.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.33\u0026thinsp;\u0026plusmn;\u0026thinsp;1.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4740\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2 value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;0.0001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;0.0001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData expressed as mean (SD). \u003cem\u003eP\u003c/em\u003e1 value compares both groups at different times while \u003cem\u003eP\u003c/em\u003e 2 value compares pre-operatives and follow-up measurements in the same group. VAS, visual analogue scale; ODI, Oswestry Disability Index\u0026nbsp;\u003c/p\u003e\n\u003ctable id=\"Tab7\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eCorrelation between changes in spinopelvic parameters and deformity parameters.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" colspan=\"4\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"4\"\u003e\n \u003cp\u003eSA\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"4\"\u003e\n \u003cp\u003eHOD\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003ePLF\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003ePLIF\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003ePLF\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003ePLIF\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003ePLF\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003ePLIF\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ePT\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4022\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0707\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2393\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2961\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1810\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4324\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5051\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0195\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2309\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3139\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5391\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0117\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSS\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.1896\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4105\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0309\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8943\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2249\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3270\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4809\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0273\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2076\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3666\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5392\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0116\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eLL\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.0175\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.9401\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.0143\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.9509\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5393\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0116\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4890\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0245\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.6658\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0010\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5074\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0189\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eTPA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4084\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0660\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2012\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3819\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5188\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0160\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.7287\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0002\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4682\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0323\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.6224\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0026\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSVA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3125\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1679\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0408\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8607\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4704\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0314\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5032\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0201\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4111\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0441\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4348\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0388\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData expressed as r-value (strength of correlation), and P-value (significance of correlation). PT, Pelvic tilt; SS, sacral slope; LL, Lumbar lordosis; TPA, T1 pelvic angle; SVA, Sagittal vertical axis; SD, Slip degree; SA, Slip angle; DH, Disc height.\u003c/p\u003e\n\u003ctable id=\"Tab8\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eCorrelation between changes in clinical outcomes and changes in radiographic parameters\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" colspan=\"4\"\u003e\n \u003cp\u003eVAS\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"4\"\u003e\n \u003cp\u003eODI\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003ePLF\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003ePLIF\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003ePLF\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003ePLIF\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003er\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ePT\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.2337\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3078\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3097\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1719\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0961\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.6786\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3380\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1340\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSS\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1729\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4537\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4132\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0626\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2446\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2852\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3654\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1033\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eLL\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.6275\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0023\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4875\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0250\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5874\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0051\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4707\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0313\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eTPA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0005\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.9984\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2735\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2302\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2809\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2175\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3250\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1506\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSVA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1866\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4180\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1485\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5206\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2434\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2876\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0891\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.7010\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.1974\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3910\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e-0.1430\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5364\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.1852\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4215\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.0494\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8317\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSA\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4663\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0331\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5394\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0116\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4916\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0236\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5273\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0140\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eDH\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5796\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0059\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.5881\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0050\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.6649\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0010\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.6570\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0012\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData expressed as r-value (strength of correlation), and P-value (significance of correlation). VAS, visual analogue scale; ODI, Oswestry Disability Index; PT, Pelvic tilt; SS, sacral slope; LL, Lumbar lordosis; TPA, T1 pelvic angle; SVA, Sagittal vertical axis; SD, Slip degree; SA, Slip angle; DH, Disc height.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThere have been many reports comparing PLF and PLIF for treating isthmic spondylolisthesis, with a focus on their fusion rates and clinical outcomes, either alone or in combination [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. However, only a few reports have explored the comparison between the two techniques in terms of their effect on sagittal radiographic parameters or their clinical correlation [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn this study, we evaluated changes in sagittal radiographic parameters and their their correlation with clinical outcomes as assessed by VAS score and Oswestry disability index (ODI).\u003c/p\u003e \u003cp\u003eIn the nonrandomised controlled prospective study of Feng et al. [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], they evaluated the effect of PLF and PLIF on spinopelvic sagittal balance in a patient with low-grade isthmic spondylolisthesis. Both procedures could reduce the PT and increase the SS postoperatively, with no significant differences. The LL increased in the PLIF group but decreased in the PLF group. The SD improved significantly in both groups. The DH of the PLIF group showed a significant increase postoperatively,while the postoperative DH of the PLF group showed no significant difference from the preoperative value. The SA increased significantly after the operation in the PLIF group while in the PLF group, without the cage, the SA decreased.\u003c/p\u003e \u003cp\u003eIn the current study, significant improvement in all spinopelvic parameters (except for PI) was observed within the PLIF group when comparing measurements taken preoperatively and at the latest follow-up. In the PLF group, only PT, SS and LL exhibited a statistically significant improvement between preoperative and latest follow-up measurements. Both procedures have the capacity to restore the physiological status of local spinopelvic parameters (PT, SS and LL). The improvement of these parameters has been shown to be correlated with positive clinical outcomes [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], which could explain the similar short term clinical outcomes observed in both groups.\u003c/p\u003e \u003cp\u003eRegarding the deformity parameters, within the PLIF group, there was a statistically significant improvement in SA, SD, and DH from the preoperative to the latest follow-up measurements. On the other hand, in the PLF group, only SD showed a statistically significant improvement.\u003c/p\u003e \u003cp\u003eWhen comparing postoperative measurements of both groups, only the deformity parameters (SA, SD and DH) were significantly better in PLIF group. This is mainly due to the great ability of PLIF to reduce slippage, correct kyphosis and restore disc height.\u003c/p\u003e \u003cp\u003eHowever, when comparing the means of correction (postoperative values- preoperative values), all radiographic parameters (except for PI) were found to be significantly better in PLIF group. Comparing the postoperative measurements may not capture the full picture of the intervention's effectiveness, while the change score approach provides a more comprehensive understanding of the impact of the treatment on the participants' outcomes. Therefore, PLIF is more powerful than PLF in correcting both spinopelvic and deformity parameters.\u003c/p\u003e \u003cp\u003eAdditionally, when comparing the means of correction loss (last follow up values- postoperative values), only the SA and DH were significantly lower in PLIF group. This could be explained by the use of cages in the PLIF group, which maintains the achieved correction.\u003c/p\u003e \u003cp\u003eIn the context of exploring the correlation between changes in spinopelvic parameters and deformity parameters, several noteworthy findings have emerged from previous research. Park et al. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] reported that the changes in DH showed a significant positive correlation with the changes in LL and SVA, while the changes in SD and SA showed no correlation with changes in spinopelvic parameters. In a separate study, Feng et al. [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] reported that the changes in SD and DH had a significant positive correlation with the changes in LL in the PLIF group, while in the PLF group, only the changes in SD had a significant negative correlation with the changes in LL.\u003c/p\u003e \u003cp\u003eMoreover, Kawakami et al. [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e] reported that the decrease in SD, the increase in LL, and subsequent restoration of sagittal alignment improved clinical outcomes in patients undergoing posterolateral fusion for the treatment of degenerative spondylolisthesis.\u003c/p\u003e \u003cp\u003eBoachie-Adjei et al. [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e] performed partial lumbosacral kyphosis reduction in patients with high-grade spondylolisthesis. They suggested that the partial reduction in the SA, not the SD, was more important in restoring sagittal balance and a better biomechanical environment for fusion. Furthermore, Godde et al. [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] reported that restoration of segmental lordosis and LL using a wedge-shaped cage should be performed for restoring sagittal alignment.\u003c/p\u003e \u003cp\u003eIn our study, the changes in SA and DH showed a significant positive correlation with the changes in PT, SS, LL, SVA and TPA in the PLIF group while in the PLF group, changes in SA and DH showed significant positive correlation with only the changes in LL, SVA and TPA. This emphasizes the importance of restoration of DH and SA for better correction of both local and global sagittal parameters. On the other hand, complete reduction as measured by SD is not as important as restoration of DH and SA. These results are consistent with those from Boachie-Adjei et al. and Godde et al studies [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eRegarding the clinical outcome and the correlation between changes in clinical outcomes and changes in radiographic parameters, two separate prospective studies conducted by Ekman et al. [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] and Musluman et al. [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] to compare the clinical outcome after PLIF and PLF for the treatment of ischemic spondylolisthesis. Both studies found no significant difference in the clinical outcome between the two procedures as measured by ODI and VAS. These findings were also supported by a meta-analysis conducted by Luo et al. [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], who stated that there was no significant difference in the global assessment of clinical outcomes between the two fusion procedures. Farrokhi et al. [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] described a significantly better improvement in ODI for patients treated with PLF than those who underwent PLIF for IS. In a recent study conducted by Behzadnia et al. [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], the authors reported significant improvement in VAS after both procedures; however, this improvement was significantly higher in the PLIF group. They also found a significant positive correlation between the changes in VAS and changes in PT.\u003c/p\u003e \u003cp\u003eIn the present study, both ODI and VAS improved significantly at the last follow up with no significant difference between PLIF and PLF. Additionally, in both groups, changes in ODI and VAS showed a significant positive correlation with changes in SA, DH and LL.\u003c/p\u003e"},{"header":"Limitations","content":"\u003cp\u003eThe global disruption caused by the COVID-19 pandemic has had a profound impact on regular healthcare access, leading to challenges in enrolling participants and maintaining regular follow-up and consequently impeding comprehensive data collection. This disruption serves as the root cause behind the primary limitations of this study: the relatively small study population and the short follow-up duration. Therefore, multicenter studies with larger participant numbers and extended follow-up periods should be conducted to thoroughly examine the effect of postoperative radiographic parameters correction on long-term clinical outcomes.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003ePLIF exhibits greater efficacy than PLF in correcting sagittal radiographic parameters. However, this disparity does not appear to impact short-term clinical outcomes. It is essential to emphasize that further studies involving extended follow-up periods are necessary to ascertain whether this distinction will influence long-term clinical results. In both groups, changes in DH, SA and LL correlated significantly with changes in ODI and VAS; thus, restoration of disc height, correction of the slip angle and reestablishment of normal lumbar lordosis are the most important steps in surgical treatment of IS.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003ePLF\u0026nbsp; \u0026nbsp; \u0026nbsp;Posterolateral fusion\u003c/p\u003e\n\u003cp\u003ePLIF\u0026nbsp; \u0026nbsp;\u0026nbsp;Posterior lumbar interbody fusion\u003c/p\u003e\n\u003cp\u003ePI\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Pelvic incidence\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePT\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Pelvic tilt\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSS\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Sacral slope \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eLL \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Lumbar lordosis \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSVA \u0026nbsp; \u0026nbsp;Sagittal vertical axis\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTPA \u0026nbsp; \u0026nbsp;\u0026nbsp;T1 pelvic angle \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSA \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Slip angle\u003c/p\u003e\n\u003cp\u003eSD \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Slip degree\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDH \u0026nbsp; \u0026nbsp; \u0026nbsp;Disc height\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eODI \u0026nbsp; \u0026nbsp;\u0026nbsp;Oswestry Disability Index\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eVAS \u0026nbsp; \u0026nbsp;Visual analogue scale\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study was conducted in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines.\u0026nbsp;The ethical committee\u0026nbsp;of the Faculty of Medicine at Assiut University\u0026nbsp;approved the study\u0026nbsp;(IRB No.: 17100676).\u0026nbsp;This study was registered in\u0026nbsp;ClinicalTrials.gov Identifier: NCT03877341.\u0026nbsp;All participants provided written informed consent before enrollment in the study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll patients provided a consent to use their radiographs for this research.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors declare no competing interests.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMGH and KMH conceived and designed the study. MFI, EME performed the surgeries. MFI, EME, and FSS conducted the measurements, collected, and analysed the data. All authors reviewed the manuscript. MFI and EME drafted the manuscript and designed the figures and tables.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo funding or grants are associated with this study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe data associated with the paper are not publicly available but are available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBehzadnia H, Yousefzadeh- Chabok S, Alijani B, Golmohammadi S, Reyhanian Z, Naseri A, et al. (2020) Spinopelvic parameters and pain in patients with low-grade spondylolisthesis. Romanian Journal of Neurology 19:275-279\u003c/li\u003e\n\u003cli\u003eBoachie-Adjei O, Do T, Rawlins BA (2002) Partial lumbosacral kyphosis reduction, decompression, and posterior lumbosacral transfixation in high-grade isthmic spondylolisthesis: clinical and radiographic results in six patients. Spine (Phila Pa 1976) 27:E161-168\u003c/li\u003e\n\u003cli\u003eBourghli A, Aunoble S, Reebye O, Le Huec JC (2011) Correlation of clinical outcome and spinopelvic sagittal alignment after surgical treatment of low-grade isthmic spondylolisthesis. Eur Spine J 20 Suppl 5:663-668\u003c/li\u003e\n\u003cli\u003eCurylo LJ, Edwards C, DeWald RW (2002) Radiographic markers in spondyloptosis: implications for spondylolisthesis progression. Spine (Phila Pa 1976) 27:2021-2025\u003c/li\u003e\n\u003cli\u003eEkman P, M\u0026ouml;ller H, Tullberg T, Neumann P, Hedlund R (2007) Posterior lumbar interbody fusion versus posterolateral fusion in adult isthmic spondylolisthesis. Spine (Phila Pa 1976) 32:2178-2183\u003c/li\u003e\n\u003cli\u003eFarrokhi MR, Rahmanian A, Masoudi MS (2012) Posterolateral versus posterior interbody fusion in isthmic spondylolisthesis. J Neurotrauma 29:1567-1573\u003c/li\u003e\n\u003cli\u003eFeng Y, Chen L, Gu Y, Zhang ZM, Yang HL, Tang TS (2015) Restoration of the spinopelvic sagittal balance in isthmic spondylolisthesis: posterior lumbar interbody fusion may be better than posterolateral fusion. Spine J 15:1527-1535\u003c/li\u003e\n\u003cli\u003eGlassman SD, Bridwell K, Dimar JR, Horton W, Berven S, Schwab F (2005) The impact of positive sagittal balance in adult spinal deformity. Spine (Phila Pa 1976) 30:2024-2029\u003c/li\u003e\n\u003cli\u003eG\u0026ouml;dde S, Fritsch E, Dienst M, Kohn D (2003) Influence of cage geometry on sagittal alignment in instrumented posterior lumbar interbody fusion. Spine (Phila Pa 1976) 28:1693-1699\u003c/li\u003e\n\u003cli\u003eHanson DS, Bridwell KH, Rhee JM, Lenke LG (2002) Correlation of pelvic incidence with low- and high-grade isthmic spondylolisthesis. Spine (Phila Pa 1976) 27:2026-2029\u003c/li\u003e\n\u003cli\u003eKawakami M, Tamaki T, Ando M, Yamada H, Hashizume H, Yoshida M (2002) Lumbar sagittal balance influences the clinical outcome after decompression and posterolateral spinal fusion for degenerative lumbar spondylolisthesis. Spine (Phila Pa 1976) 27:59-64\u003c/li\u003e\n\u003cli\u003eKim MK, Lee S-H, Kim E-S, Eoh W, Chung S-S, Lee C-S (2011) The impact of sagittal balance on clinical results after posterior interbody fusion for patients with degenerative spondylolisthesis: A Pilot study. BMC Musculoskeletal Disorders 12:69\u003c/li\u003e\n\u003cli\u003eLabelle H, Roussouly P, Berthonnaud E, Transfeldt E, O\u0026apos;Brien M, Chopin D, et al. (2004) Spondylolisthesis, pelvic incidence, and spinopelvic balance: a correlation study. Spine (Phila Pa 1976) 29:2049-2054\u003c/li\u003e\n\u003cli\u003eLafage R, Ferrero E, Henry JK, Challier V, Diebo B, Liabaud B, et al. (2015) Validation of a new computer-assisted tool to measure spino-pelvic parameters. The Spine Journal 15:2493-2502\u003c/li\u003e\n\u003cli\u003eLuo J, Cao K, Yu T, Li L, Huang S, Gong M, et al. (2017) Comparison of Posterior Lumbar Interbody Fusion Versus Posterolateral Fusion for the Treatment of Isthmic Spondylolisthesis. Clin Spine Surg 30:E915-e922\u003c/li\u003e\n\u003cli\u003eM\u0026uuml;sl\u0026uuml;man AM, Yılmaz A, Cansever T, Cavuşoğlu H, Colak I, Gen\u0026ccedil; HA, et al. (2011) Posterior lumbar interbody fusion versus posterolateral fusion with instrumentation in the treatment of low-grade isthmic spondylolisthesis: midterm clinical outcomes. J Neurosurg Spine 14:488-496\u003c/li\u003e\n\u003cli\u003eOh SK, Chung SS, Lee CS (2009) Correlation of pelvic parameters with isthmic spondylolisthesis. Asian Spine J 3:21-26\u003c/li\u003e\n\u003cli\u003eOikonomidis S, Meyer C, Scheyerer MJ, Grevenstein D, Eysel P, Bredow J (2020) Lumbar spinal fusion of low-grade degenerative spondylolisthesis (Meyerding grade I and II): Do reduction and correction of the radiological sagittal parameters correlate with better clinical outcome? Arch Orthop Trauma Surg 140:1155-1162\u003c/li\u003e\n\u003cli\u003ePark SJ, Lee CS, Chung SS, Kang KC, Shin SK (2011) Postoperative changes in pelvic parameters and sagittal balance in adult isthmic spondylolisthesis. Neurosurgery 68:355-363; discussion 362-353\u003c/li\u003e\n\u003cli\u003eSchwab FJ, Blondel B, Bess S, Hostin R, Shaffrey CI, Smith JS, et al. (2013) Radiographical spinopelvic parameters and disability in the setting of adult spinal deformity: a prospective multicenter analysis. Spine (Phila Pa 1976) 38:E803-812\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":"[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":"isthmic spondylolisthesis, postrolateral fusion, posterior lumbar interbody fusion, sagittal radiographic parameters","lastPublishedDoi":"10.21203/rs.3.rs-3325681/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3325681/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e This randomized controlled study aims to specifically investigate and compare the effects of posterolateral fusion (PLF) and posterior lumbar interbody fusion (PLIF) on sagittal radiographic parameters, and to evaluate the correlation between the changes in these parameters and the clinical outcome.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e A total of 42 patients with single level low-grade isthmic spondylolisthesis were included in the study. The patients were randomly allocated into 2 groups: PLF group (21 patients) and PLIF (group 21 patients). The mean age was 40.23 ± 10.25 years in the PLF group and \u0026nbsp;35.81 ± 10.58 in the PLIF group. Of the \u0026nbsp;42 patients, 13 cases were male and 29 cases were female. All patients had a follow-up period of at least 24 months. Radiographic outcomes included pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), sagittal vertical axis (SVA), T1 pelvic angle (TPA), slip angle (SA), slip degree (SD) and disc height (DH). Clinical outcomes were assessed by Oswestry Disability Index (ODI) and visual analogue scale (VAS).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Upon comparing postoperative measurements of both groups, only SA, SD and DH were significantly better in PLIF group. However, when comparing the means of correction (postoperative values- preoperative values), all radiographic parameters were found to be significantly better in PLIF group. Additionally, SA and DH showed significantly less correction loss in the PLIF group. ODI and VAS scores improved significantly in both groups during the final follow-up, with no significant differences between the two groups. Changes in ODI and VAS were significantlycorrelated with changes in SD, DH, and LL.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e PLIF exhibits greater strength in correcting sagittal radiographic parameters. Nevertheless, this difference does not seem to influence short-term clinical results. Notably, changes in DH, SA, and LL displayed significant correlations with changes in ODI and VAS, underscoring the importance of restoring disc height, rectifying slip angle, and reestablishing normal lumbar lordosis as crucial steps in the surgical management of isthmic spondylolisthesis.\u003c/p\u003e\n\u003cp\u003eTrial registration ClinicalTrials.gov Identifier: NCT03877341, registered on March 15, 2019.\u003c/p\u003e","manuscriptTitle":"Effect of posterolateral fusion versus posterior lumbar interbody fusion on sagittal radiographic parameters in adult patients with low-grade isthmic spondylolisthesis: a randomized controlled trial","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-09-09 01:45:20","doi":"10.21203/rs.3.rs-3325681/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":"8d762520-ea86-4462-9002-d985fe2d2f2a","owner":[],"postedDate":"September 9th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2023-10-29T08:29:22+00:00","versionOfRecord":[],"versionCreatedAt":"2023-09-09 01:45:20","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3325681","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3325681","identity":"rs-3325681","version":["v1"]},"buildId":"FbvkV6FR0MCFSLy54lSbu","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}