L4-L5 anatomy classification system for lateral lumbar interbody fusion.

Lateral lumbar interbody fusion (LLIF), developed by Dr. Luiz Pimenta in 2006, allows access to the spinal column through the psoas major muscle. The technique has many advantages, such as reduced bone and muscular tissue damage, indirect decompression, larger implants, and lordosis correction capabilities. However, this technique also has drawbacks, with the most notorious being the risk of spinal pathologies due to indirect injury of the lumbar plexus, but with low rates of persistent injuries. Therefore, several groups have proposed classifications to help identify patients at a greater risk of presenting with neurological deficits. The present work proposes a classification system that relies on simple observation of easily identifiable key structures to guide lateral L4-L5 LLIF decision-making. Patients aged > 18 years who underwent preoperative magnetic resonance imaging (MRI) between 2022 and 2023 were included until 50 high-quality images were acquired. And excluded as follow Anatomical changes in the vertebral body or major psoas muscles prevent the identification of key structures or poor-quality MRIs. Each anatomy was classified as type I, type II, or type III according to the consensus among the three observers. Fifty anatomical sites were included in this study. 70% of the L4-L5 anatomy were type I, 18% were type II, and 12% were type III. None of the type 3 L4-L5 anatomies were approached using a lateral technique. The proposed classification is an easy and simple method for evaluating the feasibility of a lateral approach to-L4-L5.

Survey of major complications after prone transpsoas surgery: an analysis of early adopters' practice.

INTRODUCTION: The prone transpsoas technique (PTP) is a modification of the traditional lateral lumbar interbody fusion approach, which was first published in the literature in 2020. The technique provides several advantages, such as lordosis correction and redistribution, single-position surgery framework, and ease of performing posterior techniques when needed. However, the prone position also leads to the movement of some retroperitoneal, vascular, and neurological structures, which could impact the complication profile. Therefore, this study aimed to investigate the occurrence of major complications in the practice of early adopters of the PTP approach. METHODS: A questionnaire containing 8 questions was sent to 50 participants and events involving early adopters of the prone transpsoas technique. Of the 50 surgeons, 32 completed the questionnaire, which totaled 1963 cases of PTP surgeries. RESULTS: Nine of the 32 surgeons experienced a major complication (28%), with persistent neurological deficit being the most frequent (7/9). Of the total number of cases, the occurrence of permanent neurological deficits was approximately 0,6%, and the rate of vascular and visceral injuries were both 0,05% (1/1963 for each case). CONCLUSION: Based on the analysis of the questionnaire responses, it can be concluded that PTP is a safe technique with a very low rate of serious complications. However, future studies with a more heterogeneous group of surgeons and a more rigorous linkage between answers and patient data are needed to support the findings of this study.

New ipsilateral full endoscopic interlaminar approach for L5-S1 foraminal and extraforaminal decompression: technique description and initial case series.

BACKGROUND: The L5-S1 interlaminar access described in 2006 by Ruetten et al. represented a paradigm shift and a new perspective on endoscopic spinal approaches. Since then, the spinal community has shown that both the traditional ipsilateral and novel contralateral interlaminar approaches to the L5-S1 foramen are good alternatives to transforaminal access. This study aimed to provide a technical description and brief case series analysis of a new endoscopic foraminal and extraforaminal approach for pathologies at the lumbar L5-S1 level using a new ipsilateral interlaminar approach. METHODS: Thirty patients with degenerative stenotic conditions at the L5-S1 disc level underwent the modified interlaminar approach. The surgical time, blood loss, occurrence of complications, and clinical outcomes were recorded. The data were compiled in Excel and analyzed using R software version 4.2. All continuous variables are presented as the mean, median, minimum, and maximal ranges. For categorical variables, data are described as counts and percentages. RESULTS: Thirty patients were included in the study. The cohort showed significant improvements in all quality-of-life scores (ODI, visual analog scale of back pain, and visual analog scale of leg pain). Five cases of postoperative numbness and three cases of postoperative dysesthesia have been reported. No case of durotomy or leg weakness has been reported. CONCLUSIONS: The fundamental change proposed by this procedure, the new ipsilateral approach, presents potential advantages to surgeons by overcoming anatomical challenges at the L5-S1 level and by providing surgeon-friendly visualization and access. This approach allows for extensive foraminal and extraforaminal decompression, including the removal of hernias and osteophytosis, without causing neural retraction of the L5-S1 roots while maintaining the stability of the operated level.

Evaluation of the use of tranexamic acid in the postoperative period in patients with scoliosis undergoing posterior fusion.

Scoliosis is the most prevalent type of spinal deformity, with a 2-3% prevalence in the general population. Moreover, surgery for scoliotic deformity may result in severe blood loss and, consequently, the need for blood transfusions, thereby increasing surgical morbidity and the rate of complications. Several antifibrinolytic drugs, such as tranexamic acid, have been regarded as safe and effective options for reducing blood loss. Therefore, the present study aimed to analyse the effectiveness of this drug for controlling bleeding when used intraoperatively and in the first 48 h after surgery. A prospective randomized study of a cohort of patients included in a mass event for scoliosis treatment using PSF was performed. Twenty-eight patients were analysed and divided into two groups: 14 patients were selected for intraoperative and postoperative use of tranexamic acid (TXA), and the other 14 were selected only during the intraoperative period. The drainage bleeding rate, length of hospital stay, number of transfused blood units, and rate of adverse clinical effects were compared. All the patients involved had similar numbers of fusion levels addressed and similar scoliosis profiles. The postoperative bleeding rate through the drain did not significantly differ between the two groups (p > 0.05). There was no significant difference in the number of transfused blood units between the groups (p = 0.473); however, in absolute numbers, patients in the control group received more transfusions. The length of hospital stay was fairly similar between the groups, with no statistically significant difference. Furthermore, the groups had similar adverse effects (p = 0.440), with the exception of nausea and vomiting, which were twice as common in the TXA group postoperatively than in the control group. No significant differences were found in the use of TXA during the first 48 postoperative hours or in postoperative outcomes.

Lateral versus posterior approaches to treat degenerative lumbar pathologies-systematic review and meta-analysis of recent literature.

INTRODUCTION: The lateral lumbar interbody fusion arose as a revolutionary approach to treating several spinal pathologies because the techniques were able to promote indirect decompression and lordosis restoration through a minimally invasive approach allowing for reduced blood loss and early recovery for patients. However, it is still not clear how the technique compares to other established approaches for treating spinal degenerative diseases, such as TLIF, PLIF, and PLF. MATERIAL AND METHODS: This is a systematic review and meta-analysis of articles published in the last 10 years comparing lateral approaches to posterior techniques. The authors included articles that compared the LLIF technique to one or more posterior approaches, treating only degenerative pathologies, and containing at least one of the key outcomes of the study. Exclusion articles that were not original and the ones that the authors could not obtain the full text; also articles without the possibility to calculate the standard deviation or mean were excluded. For count variables, the odds ratio was used, and for continuous variables, the standard means difference (SMD) was used, and the choice between random or fixed-effects model was made depending on the presence or not of significant (p < 0.05) heterogeneity in the sample. RESULTS: Twenty-four articles were included in the quantitative review. As for the intra-/perioperative variables, the lateral approaches showed a significant reduction in blood loss (SMD-1.56, p < 0.001) and similar operative time (SMD = - 0.33, p = 0.24). Moreover, the use of the lateral approaches showed a tendency to lead to reduced hospitalization days (SMD = - 0.15, p = 0.09), with significantly reduced odds ratios of complications (0.53, p = 0.01). As for the clinical outcomes, both approaches showed similar improvement both at improvement as for the last follow-up value, either in ODI or in VAS-BP. Finally, when analyzing the changes in segmental lordosis and lumbar lordosis, the lateral technique promoted significantly higher correction in both outcomes (p < 0.05). CONCLUSION: Lateral approaches can promote significant radiological correction and similar clinical improvement while reducing surgical blood loss and postoperative complications.

Comparison of segmental lordosis gain of prone transpsoas (PTP) vs. lateral lumbar interbody fusion.

INTRODUCTION: Lumbar interbody fusion is a standard method to treat certain degenerative conditions that are refractory to conservative treatments. LLIF reduces posterior muscle damage, can relieve neurological symptoms through indirect decompression, provides increased stability with its wider cages, and promotes more significant segmental lordosis than standard posterior techniques. However, the technique possesses its issues, such as unusual positioning, possible plexus-related symptoms, and median segmental lordosis correction. Trying to ease those issues, the idea of a prone transpsoas technique occurred. METHODS: Retrospective, single-centric, comparative, and non-randomized study. The authors paired patients receiving lateral lumbar interbody fusion (LLIF) or prone transpsoas (PTP) to evaluate the technique's impact on the segmental lordosis correction. A correlation test selected the covariates for the matching. p-Values inferior to 0.05 were deemed significant. RESULTS: Seventy-one patients were included in the analysis, 53 in the LLIF group and 18 in the PTP group. The significant covariates to the segmental lordosis correction were technique, preoperative segmental lordosis, cage position, and preoperative pelvic tilt. After the paring model, PTP showed significant segmental lordosis correction potential regarding the LLIF. CONCLUSION: The prone transpsoas approach can significantly enhance the correction of segmental lordosis proportionated to the traditional LLIF approach.

Minimally invasive versus open surgery for degenerative lumbar pathologies:a systematic review and meta-analysis.

INTRODUCTION: With the increase in life expectancy and consequent aging of the population, degenerative lumbar spine diseases tend to increase its number exponentially. Several treatment options are available to treat degenerative spinal diseases, such as laminectomies, posterior fusions, and interbody fusions, depending on their locations, correction necessities, and surgeon philosophy. With the advance in technology and surgical knowledge, minimally invasive techniques (MIS) arose as a solution to reduce surgical morbidity, while maintaining the same benefits as the traditionally/open surgeries. Several studies investigated the possible advantages of MIS techniques against the traditional open procedures. However, those articles are usually focused only on one technique or on one pathology. METHODS: The electronic databases, including PubMed, Google Scholar, Ovid, and BVS, were systematically reviewed. Only original articles in English or Portuguese were added to the review, the revision was performed following the PRISMA guideline. RESULTS: Fifty-three studies were included in the meta-analysis. Of the studied outcomes the Length of Stay Odds of complications, Blood Loss, and Surgery costs presented significantly favored MIS approaches, while the Last FUP ODI score, and Surgery Time did not differ among the groups. CONCLUSION: Minimally invasive techniques are a remarkably interesting option to traditional open surgeries, as these procedures showed a significant reduction in blood loss, hospitalization time, complications, and surgical costs.

The prone transpsoas technique: preliminary radiographic results of a multicenter experience.

INTRODUCTION: The lateral lumbar interbody fusion (LLIF) is a safe and effective technique to treat a vast range of lumbar disorders. However, the technique is also burdened by some problems. A new approach to the lateral lumbar interbody fusion was devised to solve or reduce some of the problems regarding the lateral approach. Its principal difference from the standard LLIF relies on positioning the patient in a prone decubitus, which might lead to an increase in the intradiscal lordosis. METHODS: A retrospective, multicentric, non-randomized study to evaluate segmental and regional lordosis following prone transpsoas (PTP) approach to LLIF. All patients undergoing prone transpsoas surgery at the involved institutions were included. Patients with low-quality images not allowing the measurements of the required spinopelvic parameters were excluded. Measurements included pre- and postoperative index-level segmental lordosis, lumbar lordosis, pelvic incidence, and pelvic tilt. RESULTS: Thirty-two (32) patients were included in the study, in which 23 underwent single-level, six (6) underwent two-level, Two (2) underwent three-level, and one underwent four-level PTP. Mean index level segmental lordosis increased from 8.7° to 14.8°(p < 0.001); lumbar lordosis (L1-S1) increased from 42.1° to 45.8° (p = 0.11), although after excluding an outlier value L1-S1 lordosis results were 41.9° pre-op to 46.7° post-op (p = 0.003). Twenty-two (22) patients had a pre-op PI-LL mismatch of 10° or more, while at the postoperative visit, only 12 patients had a mismatch outside of 10° (p = 0.01). CONCLUSION: The prone transpsoas technique is feasible and is associated with a significant gain of segmental lordosis and correction of spinopelvic alignment parameters.

Correction to: The prone transpsoas technique: preliminary radiographic results of a multicenter experience.

Unfortunately, the third and fourth author names have been incorrectly published in the original publication. The complete correct names are given below.

Translation and Cross-cultural Adaptation of the SOSG-OQ 2.0 Questionnaire into Brazilian Portuguese.

Objective: To perform the cross-cultural adaptation and translation into Brazilian Portuguese of the Spine Oncology Study Group - Outcomes Questionnaire 2.0 (SOSG-OQ 2.0) to enable its application to Brazilian patients and to allow Brazilian researchers to use a questionnaire that is on trend in the scientific literature. Materials and Methods: The present is a basic, non-randomized, non-comparative study. The translation followed the proposal by Reichenheime and Moraes, mainly for the semantic equivalence and measurement equivalence sessions, as well as the recommendations by Coster and Mancini mainly in the translation stage. The stages were as follows: first - translation into Brazilian Portuguese; second - back-translation; third - semantic comparison; fourth - validation of the final construct. Results: The translations of the SOSG-OQ 2.0 made by three translators presented a high degree of similarity for most questions. The translators kept all question titles and subtitles, as well as their internal and external orders. Two sworn translators, with native proficiency in English, performed the back-translation of the amalgamated text. Both back-translations were quite similar, and any differences were solved through consensus between the main author and the sworn translators, and the translated text was considered the final version. Conclusion: The present study shows a translated version of the SOSG-OQ 2.0 with semantic validity with the original version published in English. As such, researchers can apply the questionnaire to the Brazilian population, adding another tool for spine surgeons to improve the monitoring of this complex group of patients.

Advancing Prone-Transpsoas Spine Surgery: A Narrative Review and Evolution of Indications with Representative Cases.

The Prone Transpsoas (PTP) approach to lumbar spine surgery, emerging as an evolution of lateral lumbar interbody fusion (LLIF), offers significant advantages over traditional methods. PTP has demonstrated increased lumbar lordosis gains compared to LLIF, owing to the natural increase in lordosis afforded by prone positioning. Additionally, the prone position offers anatomical advantages, with shifts in the psoas muscle and lumbar plexus, reducing the likelihood of postoperative femoral plexopathy and moving critical peritoneal contents away from the approach. Furthermore, operative efficiency is a notable benefit of PTP. By eliminating the need for intraoperative position changes, PTP reduces surgical time, which in turn decreases the risk of complications and operative costs. Finally, its versatility extends to various lumbar pathologies, including degeneration, adjacent segment disease, and deformities. The growing body of evidence indicates that PTP is at least as safe as traditional approaches, with a potentially better complication profile. In this narrative review, we review the historical evolution of lateral interbody fusion, culminating in the prone transpsoas approach. We also describe several adjuncts of PTP, including robotics and radiation-reduction methods. Finally, we illustrate the versatility of PTP and its uses, ranging from 'simple' degenerative cases to complex deformity surgeries.

Impact of the Preoperative Spinopelvic Parameters on the Segmental Lordosis Correction after One-level Lateral Lumbar Interbody Fusion.

Objectives The present study aimed to assess whether preoperative spinopelvic parameters can influence the gain of segmental lordosis after one level of lateral lumbar interbody fusion. Methods The following radiological parameters were measured in the X-rays: pelvic incidence, lumbar lordosis, pelvic tilt, L4S1 lordosis, index level segmental lordosis, intraoperative index segmental lordosis, pelvic mismatch (IP-LL), distal lordosis proportion, delta segmental lordosis, Pelvic Titlt (PT) > 20, actual sacral slope, and ideal sacral slope, and the correlation of these variables with the gain of segmental lordosis was investigated. Afterwards, an exploratory cluster analysis was performed to identify common characteristics between patients and segmental lordosis gain. Results The sample of the present study comprised 104 patients, of which 76% presented segmental lordosis gain. The most correlated parameters with the segmental lordosis gain were preoperative segmental lordosis (-0.50) and delta intraoperative lordosis (0.51). Moreover, patients in the high PI groups had a trend to gain more segmental lordosis ( p < 0.05) and a reduced risk of losing segmental lordosis (Odds 6.08). Conclusion Patients with low-medium PI profiles presented higher odds of loss of segmental lordosis. However, the preoperative spinopelvic parameters alone do not seem to play a significant role in the fate of segmental lordosis gain.

Assessing the Capabilities of Transcranial Magnetic Stimulation (TMS) to Aid in the Removal of Brain Tumors Affecting the Motor Cortex: A Systematic Review.

Introduction: The brain tumor is frequently related to severe motor impairment and impacts the quality of life. The corticospinal tract can sometimes be affected depending on the type and size of the neoplasm, so different tools can evaluate motor function and connections. It is essential to organize surgical procedures and plan the approach. Functional motor status is mapped before, during, and after surgery. Studying corticospinal tract status can help map the functional areas, predict postoperative outcomes, and help the decision, reducing neurological deficits, aiming to preserve functional networks, using the concepts of white matters localization and fibbers connections. Nowadays, there are new techniques that provide functional information regarding the motor cortex, such as transcranial magnetic stimulation (TMS), direct cortical stimulation (DCS), and navigated TMS (nTMS). These tools can be used to plan a customized surgical strategy and the role of motor evoked potentials (MEPs) is well described during intra-operative, using intraoperative neuromonitoring. MEPs can help to localize primary motor areas and delineate the cut-off point of resection in real-time, using direct stimulation. In the post-operative, the MEP has increased your function as a predictive marker of permanent or transitory neurological lesion marker. Methods: Systematic review performed in MEDLINE via PUBMED, EMBASE, and SCOPUS databases regarding the post-operative assessment of MEP in patients with brain tumors. The search strategy included the following terms: (("Evoked Potentials, Motor"[Mesh]) AND "Neoplasms"[Mesh]) AND "Transcranial Magnetic Stimulation"[Mesh] AND "Brain Tumor"[Mesh]), the analysis followed the PRISMA guidelines for systematic reviews, the review spanned until 06/04/2021, inclusion criteria were studies presenting confirmed diagnosis of brain tumor (primary or metastatic), patients >18 y/o, using TMS, Navigated TMS, and/or Evoked Potentials as tools in preoperative planning or at the intra-operative helping the evaluation of the neurological status of the motor cortex, articles published in peer-reviewed journals, and written in English or Portuguese. Results: A total of 38 studies were selected for this review, of which 14 investigated the potential of nTMS to predict the occurrence of motor deficits, while 25 of the articles investigated the capabilities of the nTMS technique in performing pre/intraoperative neuro mapping of the motor cortex. Conclusion: Further studies regarding motor function assessment are needed and standardized protocols for MEPs also need to be defined.

Single-Position Prone Transpsoas Lateral Interbody Fusion Including L4L5: Early Postoperative Outcomes.

BACKGROUND: The lateral lumbar interbody fusion (LLIF) was a revolutionary approach devised by Luiz Pimenta that allowed the surgeon to access the lumbar spine through the major psoas muscle. Although the traditional LLIF had enabled enormous advances, the technique has its drawbacks. A new concept to perform the traditional LLIF has been proposed, with the patient being prone to decubitus with slightly extended legs. Our study aims to analyze the early outcomes of patients who had undergone the prone transpsoas (PTP) for degenerative spine pathologies including the L4/5 level. METHODS: This study was multicentric, retrospective, nonrandomized, noncomparative, and observational. Only participants who received PTP in L4/5, with no more than 3 levels of intersomatics and fixation no further than S1, were included. The primary outcomes were the onset of new neurologic deficits and postoperative complications. Also, surgery details, such as blood loss and surgery duration, were measured. Neurologic deficits were accessed at the postoperative visit, which ranged from 7 to 14 days after surgery. RESULTS: Twenty-seven patients fulfilled the inclusion and exclusion criteria, with the majority receiving PTP only in L4/5 (66.6%). The mean surgery time was 182, with 29 minutes of mean transpsoas time. Of the patients, only 1 presented the onset of a motor deficit, while 3 patients presented a new sensory deficit. Five complications occurred, none intraoperative and 5 postoperative, with only 1 directly correlated with the access. CONCLUSIONS: The prone transpsoas is safe and feasible for approaching the L4/5 disk, presenting with a low rate of complication and new-onset neurologic deficits.

The Effect of Patient Position on Psoas Morphology and in Lumbar Lordosis.

INTRODUCTION: Among the interbody fusions, lateral lumbar interbody fusion allows access to the lumbar spine through the major psoas muscle, which offers several advantages to the spine surgeon. However, some of its drawbacks cause surgeons to avoid using it as a daily practice. Therefore, to address some of these challenges, we propose the prone transpsoas technique, differing mainly from the traditional technique on patient position-moving from lateral to prone decubitus, theoretically enhancing the lordosis and impacting the psoas morphology. METHODS: Twenty-four consecutive patients were invited to have magnetic resonance imaging examinations in 3 different positions (prone, dorsal, lateral). Two observers measured the following parameters: vertebral body size, psoas diameter, psoas anterior border distance, plexus distance, total lumbar lordosis, distal lumbar lordosis, and proximal lumbar lordosis. Values of P < 0.05 were deemed significant. RESULTS: The prone position yielded a significant increase in the lumbar lordosis, both in L1-S1 (57° vs. 46.5°) and proximal lordosis (40.4° vs. 36.9°) compared with the lateral position. Regarding the morphologic aspects, patients in the prone position presented lesser psoas muscles forward shift, but no difference was noted in the plexus position neither for L3-L4 nor L4-L5. CONCLUSIONS: The prone position resulted in a significantly increased lumbar lordosis, both distal and proximal, which may enable the spine surgeon to achieve significant sagittal restoration just by positioning. The prone position also produced a posterior retraction of the psoas muscle. However, it did not significantly affect the position of the plexus concerning the vertebral body.

Pedicle Screws and Facet Violation - The importance of the Angle between the Facet and the Screw.

Objective To verify whether, regardless of the screw placement technique, there is a safe distance or angle in relation to the facets that can prevent violation of the facet joint when the screws are placed. Methods Retrospective, single, comparative, non-randomized center. We evaluated by axial computed tomography: the angle of the screw/rod in relation to the midline, the angle of the center of the facets in relation to the midline, the distance between the head of the screw/rod to the midline, and the distance from the center of the facets to the midline; the violation of the facet joint will be evaluated in a gradation of 0 to 2. Also will be measured the difference between the angle os the facets and the angle of the screws (Δ Angle) and, the difference between the facet distance and the screw distance (Δ Distance). Results A total of 212 patients and 397 facets were analyzed (196 on the left and 201 on the right). Of these, 303 were not violated (grade 0), corresponding to 76,32%, and 94 suffered some type of violation (grade 1 and 2), corresponding to 23,68%. The mean of Δ angle was 9.87° +/- 4.66° (grade 0), and of 3.77° +/- 4.93° in facets (grade 1 and 2) ( p < 0.001), and the Δ mean distance in cases in which there was no violation was 0.94 arbitrary units (a.u.) +/- 0.39 a.u., while the Δ distance in G1 and G2 cases was 0.56 a.u. +/- 0.25 a.u. ( p < 0.001). Conclusion The measurements of angle and distance between facet and screw can help in the placement of screws. These parameters can be used as safety measures with the most frequent use of surgical navigation techniques.

Lumbar Total Disc Replacement by the Lateral Approach-Up to 10 Years Follow-Up.

OBJECTIVE: This study aimed to analyze radiologic and clinical results with a minimum 5 years follow-up (FUP) of lateral lumbar total disc replacement for the treatment of symptomatic lumbar degenerative disc disease. METHODS: We performed a prospective, single-center, clinical, and radiologic study. Patients were treated with lumbar total disc replacement (extreme lateral total disc replacement) by a lateral transpsoas approach. From 2005 to 2012, 60 patients were enrolled (31 male, 29 female; total, 66 levels; average age, 42.8 years [standard deviation (SD), 9.7 years, range, 22-64 years]; mean body mass index, 26.0 [SD, 3.4]). Clinical end points included visual analog scale and Oswestry Disability Index questionnaires, complications, and reoperation. Radiographic end points included heterotopic ossification (McAfee classification), adjacent level disease, and prosthesis migration or subluxation. RESULTS: The mean surgical duration was 122 minutes (SD, 45 minutes) with mean 58 mL (SD, 21 mL) of estimated blood loss. No intraoperative complication occurred. The exceptions were 1 patient with postanesthesia apnea and 2 patients with quadriceps motor deficit (resolved within 4 months with physiotherapy). Of 60 patients, 9 were missed to FUP and 51 (85%) were enrolled in the study, with mean FUP of 92 months (range, 60-122 months). In total, 5 levels (9%; 5 of 55) required to be fused. Both removal of the prostheses and interbody fusion were performed by the lateral transpsoas approach. One patient experienced CrCo allergy (at 2 months); 4 experienced persistent pain from different causes (at 7, 9, 24, and 88 months). Five patients (10%) presented with progression at adjacent levels and 2 (4%) required surgery. One patient required sacroiliac fusion at 63 months. There were no complications during the retrieval surgeries. One partial disc migration occurred but the patient refused retrieval. There was no bone bridging in 9% of the discs (grade 0 heterotopic ossification): grade I, 22%; grade II, 31%; grade III, 20%; grade IV (fusion), 18%. Most heterotopic ossification cases (93%) occurred in the lateral aspect of the disc space, and mostly at the contralateral side of the surgical approach. Patient-reported outcomes significantly improved (P < 0.01) at the last FUP. Visual analog scale back pain score was preoperatively 8.5, early postoperatively 2.5, and at last FUP 3.1. Oswestry Disability Index was preoperatively 55%, early postoperatively 31%, and at last FUP 21%. CONCLUSIONS: This study presents mid-term to long-term results of extreme lateral total disc replacement artificial disc for the treatment of lumbar degenerative disease, with fast mobilization, sustained pain relief, and improved physical function. Despite the low rate of ALDis, some discs evolved to ankyloses and others were retrieved. Lumbar artificial disc replacement by the lateral approach seems to be a safe and effective treatment.

Translation and Cross-cultural Adaptation of the SOSG-OQ 2.0 Questionnaire into Brazilian Portuguese / Tradução e adaptação transcultural do questionário SOSG-OQ 2.0 para o português brasileiro

Abstract Objective: To perform the cross-cultural adaptation and translation into Brazilian Portuguese of the Spine Oncology Study Group - Outcomes Questionnaire 2.0 (SOSG-OQ 2.0) to enable its application to Brazilian patients and to allow Brazilian researchers to use a questionnaire that is on trend in the scientific literature. Materials and Methods: The present is a basic, non-randomized, non-comparative study. The translation followed the proposal by Reichenheime and Moraes, mainly for the semantic equivalence and measurement equivalence sessions, as well as the recommendations by Coster and Mancini mainly in the translation stage. The stages were as follows: first - translation into Brazilian Portuguese; second - back-translation; third - semantic comparison; fourth - validation of the final construct. Results: The translations of the SOSG-OQ 2.0 made by three translators presented a high degree of similarity for most questions. The translators kept all question titles and subtitles, as well as their internal and external orders. Two sworn translators, with native proficiency in English, performed the back-translation of the amalgamated text. Both back-translations were quite similar, and any differences were solved through consensus between the main author and the sworn translators, and the translated text was considered the final version. Conclusion: The present study shows a translated version of the SOSG-OQ 2.0 with semantic validity with the original version published in English. As such, researchers can apply the questionnaire to the Brazilian population, adding another tool for spine surgeons to improve the monitoring of this complex group of patients.

Resumo Objetivo: Realizar a adaptação transcultural e a tradução para o português brasileiro da versão 2.0 do Questionário de Desfechos do Spine Oncology Study Group (Spine Oncology Study Group - Outcomes Questionnaire 2.0, SOSG-OQ 2.0, em inglês) para viabilizar sua aplicação em pacientes brasileiros e permitir a utilização deste questionário que está em voga na literatura científica por pesquisadores brasileiros. Materiais e Métodos: Trata-se de uma pesquisa básica, não randomizada, não comparativa. As etapas de tradução foram realizadas conforme propostas por Reichenheime e Moraes, principalmente as sessões de equivalência semântica e equivalência de mensuração, e também foram seguidas as recomendações de Coster e Mancini, principalmente na etapa de tradução. As etapas foram as seguintes: primeira - tradução do questionário para o português brasileiro; segunda - retroversão; terceira - comparação semântica; e quarta - validação final do constructo. Resultados: As traduções do SOSG-OQ 2.0 feitas por três tradutores apresentaram grande similaridade na maioria das questões. Todos os títulos e subtítulos de perguntas foram mantidos pelos tradutores, assim como as ordens interna e externa das perguntas. A retroversão da tradução conciliada foi realizada por dois tradutores juramentados, com fluência nativa na língua inglesa. Ambas as retroversões foram bastante similares, as divergências foram sanadas por consenso entre o autor principal e os tradutores juramentados, e a versão traduzida foi considerada a versão final. Conclusão: Neste estudo, apresenta-se uma versão traduzida do SOSG-OQ 2.0 que tem validade semântica com a versão original publicada em inglês, o que permite a sua aplicação na população brasileira, e acrescenta mais uma ferramenta para que os cirurgiões de coluna possam acompanhar de forma melhor este complexo grupo de pacientes.

Klotho and PPAR Gamma Activation Mediate the Renoprotective Effect of Losartan in the 5/6 Nephrectomy Model.

Renin angiotensin system (RAS) blockade reduces the progression of chronic kidney disease (CKD) independently of its antihypertensive effect. Ang II-induced fibrosis can be mediated by molecules such as klotho, peroxisome proliferator-activate receptor γ (PPAR-γ), and the Wnt/ß-catenin pathway; however, the interaction among these molecules and RAS activation is not completely known. The aim of this study was to investigate a possible link between RAS, PPAR-γ, and Klotho in the 5/6 nephrectomy (NX) animals. NX rats presented hypertension that was blunted by both losartan and propranolol, however, only losartan was able to reduce the expression levels of fibronectin FSP1 and TGF-ß in the remnant kidney. The anti-fibrotic Klotho and PPAR-γ were reduced in the remnant kidney, and losartan, but not propranolol, restored their levels. In contrast, the profibrotic Wnt 7a and Wnt 3 were upregulated and losartan prevented the increase in Wnts. In vitro, Ang II induced a decrease in both klotho and in PPAR-γ in Madin-Darby canine kidney (MDCK) cells, and this effect was blunted by losartan. However, klotho expression was increased by pioglitazone, an agonist of PPAR-γ, and suppressed by BADGE, an antagonist of PPAR-γ, suggesting that the effect of Ang II downregulating klotho is mediated by PPAR-γ. These data suggest that activation of the Wnt pathway together with downregulation of PPAR-γ that in turn suppresses klotho contribute to potentiating the profibrotic effect of Ang II.

Impact of the Preoperative Spinopelvic Parameters on the Segmental Lordosis Correction after One-level Lateral Lumbar Interbody Fusion / Impacto dos parâmetros espinopélvicos pré-operatórios na correção de lordose segmentar após fusão intersomática lombar por via lateral de um nível

Abstract Objectives The present study aimed to assess whether preoperative spinopelvic parameters can influence the gain of segmental lordosis after one level of lateral lumbar interbody fusion. Methods The following radiological parameters were measured in the X-rays: pelvic incidence, lumbar lordosis, pelvic tilt, L4S1 lordosis, index level segmental lordosis, intraoperative index segmental lordosis, pelvic mismatch (IP-LL), distal lordosis proportion, delta segmental lordosis, Pelvic Titlt (PT) > 20, actual sacral slope, and ideal sacral slope, and the correlation of these variables with the gain of segmental lordosis was investigated. Afterwards, an exploratory cluster analysis was performed to identify common characteristics between patients and segmental lordosis gain. Results The sample of the present study comprised 104 patients, of which 76% presented segmental lordosis gain. The most correlated parameters with the segmental lordosis gain were preoperative segmental lordosis (−0.50) and delta intraoperative lordosis (0.51). Moreover, patients in the high PI groups had a trend to gain more segmental lordosis (p< 0.05) and a reduced risk of losing segmental lordosis (Odds 6.08). Conclusion Patients with low-medium PI profiles presented higher odds of loss of segmental lordosis. However, the preoperative spinopelvic parameters alone do not seem to play a significant role in the fate of segmental lordosis gain.

Resumo Objetivos O presente estudo teve como objetivo avaliar se os parâmetros espinopélvicos pré-operatórios podem influenciar o ganho da lordose segmental após fusão intersomática lombar por via lateral de um nível. Métodos Os seguintes parâmetros radiológicos foram medidos nos raios X: incidência pélvica, lordose lombar, versão pélvica, lordose L4S1, lordose segmental do nível operado, índice intraoperatório de lordose segmentar, mismatch pélvico (IP-LL), proporção de lordose distal, delta de lordose segmentar, PT > 20, inclinação sacral real e inclinação sacral ideal, e a correlação dessas variáveis com o ganho da lordose segmentar foi investigada. Posteriormente, foi realizada uma análise exploratória de cluster para identificar características comuns entre os pacientes e o ganho de lordose segmentar. Resultados O presente estudo contou com 144 pacientes, dos quais 76% apresentaram ganho de lordose segmentar. Os parâmetros mais correlacionados com o ganho de lordose segmentar foram lordose segmentar pré-operatória (−0,50) e delta intraoperatório de lordose (0,51). Além disso, os pacientes dos grupos de incidência pélvica (IP) alto tiveram tendência de ganho de lordose segmental maior (p< 0,05) e redução do risco de perda de lordose segmental (chances 6.08). Conclusão Pacientes com perfis de IP médios baixos apresentaram maiores chances de perda de lordose segmentar. No entanto, os parâmetros espinopélvicos pré-operatórios por si só não parecem desempenhar um papel significativo no destino do ganho da lordose segmentar.