Level Fusion Research Articles

Incidence and Risk Factors of Proximal Junctional Complications and Rod Fractures After Long-Segment Fusion Surgery With Anterior Column Realignment for Adult Spinal Deformity: A Minimum 2-Year Follow-Up.

To investigate the incidence and risk factors of proximal junctional kyphosis (PJK), proximal junctional failure (PJF), and rod fractures in patients undergoing long-segment (≥4 levels) fusion surgery with anterior column realignment (ACR) for adult spinal deformity. Patients aged ≥60 years with at least a 2-year follow-up were grouped based on PJK, PJF, and rod fracture occurrence. Patient, surgical, and radiographic factors were compared to identify risk factors for these complications. Independent risk factors were identified using univariate and multivariate logistic regression. Among 106 patients, the incidence rates of PJK, PJF, and rod fractures were 15.1%, 28.3%, and 17.9%, respectively. PJK was significantly associated with fewer fusion levels (odds ratio [95% CI], 0.30 [0.13-0.69]), a cranially directed uppermost instrumented vertebra (UIV) screw angle (1.40 [1.13-1.72]), postoperative overcorrection of age-adjusted pelvic incidence-lumbar lordosis (LL) (7.22 [1.13-45.93]), and a large increase in thoracic kyphosis (1.09 [1.01-1.17]). PJF risks were associated with a cranial UIV screw orientation (1.23 [1.09-1.39]), overcorrection of age-adjusted pelvic incidence-LL (10.80 [2.55-45.73]), and a smaller change in sacral slope (0.87 [0.80-0.94]). For rod fractures, prominent factors included a greater number of fusion levels (1.70 [1.17-2.46]), a larger postoperative LL (1.07 [1.01-1.15]), a smaller postoperative thoracic kyphosis (0.92 [0.86-0.98]), and smaller changes in sacral slope (0.73 [0.58-0.92]) and pelvic tilt (0.72 [0.56-0.91]). The incidence and risk factors of PJK, PJF, and rod fractures were similar to those observed in previous studies on long-segment fusion surgery without ACR. The number of ACR levels was not a significant risk factor for PJK, PJF, or rod fractures. When performing deformity correction using ACR, surgeons should carefully consider the direction of the UIV screw and ensure that overcorrection is avoided.

Distal Junctional Failure After Fusion Stopping at L5 in Patients With Adult Spinal Deformity: Incidence, Risk Factors, and Radiographic Criteria.

To identify risk factors and establish radiographic criteria for distal junctional failure (DJF) in patients with adult spinal deformity (ASD), who underwent fusion surgery stopping at L5. This retrospective study was undertaken from January 2016 to December 2020. Patients with ASD who underwent fusion surgery (≥5 levels) stopping at L5 were analyzed. DJF was defined as symptomatic adjacent segment pathology at the lumbosacral junction necessitating consideration for revision surgery. Demographic data and radiographic measurements were compared between the DJF and non-DJF groups. Receiver operating characteristic curve analysis was performed to identify the radiographic cutoff value for DJF. Among 76 patients, 16 (21.1%) experienced DJF. DJF was associated with older age, antidepressant/anxiolytic medication, longer level of fusions, and worse preoperative sagittal alignment. Antidepressant/anxiolytic medication (odds ratio, 5.60) and preoperative pelvic incidence (PI)-lumbar lordosis (LL) mismatch>40° (odds ratio, 5.87) were independent risk factors for DJF. Without both factors, the incidence of DJF has been greatly reduced (9.1%). Two radiographic criteria were determined for DJF: last distal junctional angle (DJA)>-5° and Δ last DJA-post DJA>5°. When both criteria were met, the sensitivity and specificity of the DJF were 93.3% and 91.7%, respectively. Use of antidepressant/anxiolytic medication and preoperative PI-LL mismatch >40° were independent risk factors for DJF. DJF could be diagnosed using postoperative changes in the DJA. If both criteria were met, DJF could be strongly suggested.

Association of single bolus versus bolus followed by infusion of tranexamic acid with blood loss in adolescent idiopathic scoliosis surgery

BackgroundAdolescent idiopathic scoliosis (AIS) corrective surgery may involve significant blood loss and blood transfusion requirements. Antifibrinolytic agents such as tranexamic acid (TXA) have been used to reduce blood loss, but its optimal dose is uncertain. The objective of this study is to determine the estimated blood loss and rate of blood transfusion between two groups of AIS patients receiving TXA as a single bolus versus bolus followed by infusion in scoliosis surgery.MethodsThis was a retrospective analysis of a single bolus versus bolus followed by infusion of TXA in AIS surgery. AIS patients undergoing posterior spinal fusion (PSF) from December 2018 to September 2019 at a tertiary university hospital were identified. Inclusion criteria were patients aged between 10 and 21 years who received either a single bolus of 30 mg/kg TXA (Group A) or a single bolus of 30 mg/kg followed by continuous infusion of 10 mg/kg/h of TXA (Group B). Patient demographics, operative data, estimated blood loss, blood transfusion rate, and complications were recorded.ResultsA total of 129 AIS patients were included. All operative surgeries were performed by two senior consultants. The mean age was 14.8 ± 3.4 years old, and 89.1% were female. The Cobb angle, number of fusion levels, number of screws, length of skin incision, and duration of surgery were comparable between the two groups. There was no difference in the total estimated blood loss between the two groups: 723.3 ± 279.4 mL (range: 175.0–1607.0 mL) in Group A and 819.4 ± 302.6 mL (range: 330.0–1556.0 mL) in Group B (p = 0.065). There were no complications, and none received blood transfusion.ConclusionTXA when administered as a single bolus or bolus followed by infusion in AIS patients undergoing PSF surgery was associated with similar estimated total surgical blood loss and blood transfusion requirement.

Controlling the Apex in Early Onset Scoliosis Through Active Apex Correction (APC) Non Fusion Growth Modulating Technique, Is It a Myth?

A multicenter retrospective study. To determine the rate of Apex facet fusion in children with Early Onset Scoliosis treated surgically with the Active Apex Correction (APC) technique. Seventeen patients were treated with the APC technique as index surgery for Early Onset Scoliosis with more than 1year of follow-up. A 3D CT scan was done to determine the facet fusion rate in the deformity's apex controlled with posterior tethering. The average follow-up time was 26.4months (12-56), Average age at index surgery was 81.2months (30-132), and average number of surgeries done 1.3. Apical vertebrae studied for facet fusion were the 3 vertebrae in the apex in each patient that were subjected to posterior tethering according to the APC technique. In total they were 86 apical vertebrae (172 Facets studied with 86 convex side, 86 concave side). Our observations showed that 29 facet joints were fused (16% of the total facets studied),15 were on the convex, 14 on the concave side (no statistically significant difference). Regarding the facet joint distance in the non-fused facets was 0.99mm on the convex side and 1.08mm on the concave side with no statistical significance difference. APC for Early Onset Scoliosis achieves apical growth modulation and control utilizing posterior tethering without inducing fusion. This study demonstrated that APC is an effective non-fusion technique through the low incidence of facet fusion levels at the Apex, limiting the crankshaft phenomena seen in cases with apex control through arthrodesis.

Paraspinal muscle volume and fatty infiltration after circumferential minimally-invasive deformity correction

IntroductionParaspinal muscle robustness is an area of growing interest in spinal deformity that may impact biomechanical integrity and patient quality-of-life after reconstructive surgery. Changes in paraspinal musculature after circumferential minimally-invasive (cMIS) deformity correction have not yet been investigated. MethodsWe identified patients who underwent cMIS deformity correction and had lumbar spine MRIs at baseline and at minimum 1-year postoperatively. Using T2-weighted MRI, we measured total muscular volume of the psoas major, erector spinae, and multifidus muscles. We used the threshold method to determine fatty infiltration as percent fat area (PFA) along the length of these scanned regions, encompassing the final surgical construct. ResultsWe identified 10 patients who met inclusion criteria. On average, patients underwent interbody fusion at 3.8 ± 0.9 disc levels and posterior instrumentation at 4.6 ± 1.7 vertebral levels. All constructs included lateral interbody fusion (average 2.7 ± 0.8 levels); 6 were from a right-sided approach. Postoperative MRIs were obtained at 28 ± 14.2 months.There were no significant changes in pre- and postoperative volumes or PFA in any muscle group. There were no significant differences in left/right psoas volume or PFA in patients when stratified by side of lateral approach, nor did the number of lateral interbody fusion levels correlate with psoas volume or PFA. Change in posterior paraspinal musculature characteristics did not correlate with increasing number of fixated levels, nor significantly differ in patients who underwent posterior decompression. Preoperative muscle volumes were strongly correlated with postoperative volumes. ConclusionsIn this pilot series, paraspinal and psoas muscle volumes were preserved after circumferential MIS deformity correction. Fatty infiltration was not increased in paraspinal muscles after multi-level percutaneous instrumentation, nor in the psoas after multi-level trans-psoas approaches. These findings call for more in-depth investigation in a larger cohort of patients with comparison to open deformity correction patients to determine the impact of muscle volume changes on clinical outcomes.

Intelligence model on sequence-based prediction of PPI using AISSO deep concept with hyperparameter tuning process

Protein–protein interaction (PPI) prediction is vital for interpreting biological activities. Even though many diverse sorts of data and machine learning approaches have been employed in PPI prediction, performance still has to be enhanced. As a result, we adopted an Aquilla Influenced Shark Smell (AISSO)-based hybrid prediction technique to construct a sequence-dependent PPI prediction model. This model has two stages of operation: feature extraction and prediction. Along with sequence-based and Gene Ontology features, unique features were produced in the feature extraction stage utilizing the improved semantic similarity technique, which may deliver reliable findings. These collected characteristics were then sent to the prediction step, and hybrid neural networks, such as the Improved Recurrent Neural Network and Deep Belief Networks, were used to predict the PPI using modified score level fusion. These neural networks’ weight variables were adjusted utilizing a unique optimal methodology called Aquila Influenced Shark Smell (AISSO), and the outcomes showed that the developed model had attained an accuracy of around 88%, which is much better than the traditional methods; this model AISSO-based PPI prediction can provide precise and effective predictions.

A Multi-Scale Deep Learning Algorithm for Enhanced Forest Fire Danger Prediction Using Remote Sensing Images

Forest fire danger prediction models often face challenges due to spatial and temporal limitations, as well as a lack of universality caused by regional inconsistencies in fire danger features. To address these issues, we propose a novel algorithm, squeeze-excitation spatial multi-scale transformer learning (SESMTML), which is designed to extract multi-scale fire danger features from remote sensing images. SESMTML includes several key modules: the multi-scale deep feature extraction module (MSDFEM) captures global visual and multi-scale convolutional features, the multi-scale fire danger perception module (MFDPM) explores contextual relationships, the multi-scale information aggregation module (MIAM) aggregates correlations of multi-level fire danger features, and the fire danger level fusion module (FDLFM) integrates the contributions of global and multi-level features for predicting forest fire danger. Experimental results demonstrate the model’s significant superiority, achieving an accuracy of 83.18%, representing a 22.58% improvement over previous models and outperforming many widely used deep learning methods. Additionally, a detailed forest fire danger prediction map was generated using a test study area at the junction of the Miyun and Pinggu districts in Beijing, further confirming the model’s effectiveness. SESMTML shows strong potential for practical application in forest fire danger prediction and offers new insights for future research utilizing remote sensing images.

Incidence and Risk Factors of Sacral Fracture Following Lumbosacral Fusion for Degenerative Spinal Stenosis with a Minimum Follow-Up of 2 Years: A Case–Control Study

This study aimed to investigate the incidence and risk factors for sacral fractures following lumbosacral fusion. We conducted a retrospective review of patients who underwent lumbosacral fusion for degenerative spinal stenosis with a minimum follow-up of 2years. Patients who developed and those who did not develop a sacral fracture were categorized into the "sacral fracture" and "nonfracture" groups. The demographic and radiological data were compared between the 2 groups. A total of 65 patients were included in this study. Among them, 7 patients were categorized into the sacral fracture and 58 patients into the nonfracture groups, respectively. The incidence of sacral fracture was 10.8%. In the sacral fracture group, age and fusion levels were significantly higher (P<0.05), while bone mineral density (BMD) T-score was significantly lower (P<0.05) than nonfracture group. Pelvic incidence, preoperative pelvic tilt, postoperative sacral slope, and postoperative lumbar lordosis were significantly higher (P<0.05) in the sacral fracture than the nonfracture group. Multivariable logistic regression analysis showed that BMD T-score (odds ratio [OR] 0.25, 95% confidence interval [CI] 0.08-0.79, P=0.019), postoperative sacral slope (OR 1.14, 95% CI 1.00-1.29, P= 0.047), and changes in L4-S1 lordosis (OR 1.11, 95% CI 1.00-1.23, P= 0.049) were significant factors. The overall incidence of sacral fracture was 10.8%. In our study, advanced age, low BMD, long fusion levels, and preoperative compensatory pelvic retroversion and excessive correction of it were risk factors for sacral fractures.

Space Traffic Management: Data Fusion

This article provides an overview of and terminology associated with the topic of data fusion, especially as it relates to, and for the purposes of promoting space sustainability and enabling Space Traffic Coordination (STC) and Space Traffic Management (STM). First, the terminology and organizations (data contributors and aggregators) associated with data fusion is discussed. Next, the various “levels” of data fusion are delineated, and a detailed breakdown of the data levels associated with STC and STM (and indeed all space operations) is provided. The taxonomy of data required for safe collaborative space activities are detailed. And finally, data fusion is explored in the context of STC and STM, including the levels, techniques, data sources, and state representations used. And finally, the benefits and limitations of the various data fusion types and levels are outlined with practical examples provided.

Feature level fusion of multi-source data for network intrusion detection

&lt;span lang="EN-US"&gt;The generation of data, collecting, and refining in computer networks have increased exponentially in recent years. Network attacks have also grown in prevalence with this proliferation of data and are now an inherent issue in complicated networks. Current network intrusion detection systems (NIDS) have significant issues with regard to anomaly detection. Several machine learning classification approaches are used to create NIDSs, but they are not sufficiently sophisticated to reliably detect complicated or synthetic attacks, especially if working with a lot of multi-scale data. Data fusion has been used in network intrusion detection to address these issues. For network intrusion detection, we suggested a multi-source data fusion technique in this research, which combines specific features from two datasets to produce a single dataset. Also, a machine learning classifier with fewer parameters is utilized for the fused dataset. The random forest shows the best classification accuracy compared to others in this work. For the normal classification, model accuracy is 92.8%, and the proposed fusion model showed 97.3% accuracies. Furthermore, the findings show that, when compared to other cutting-edge techniques, the suggested model is substantially more effective in detecting intrusions.&lt;/span&gt;

One- versus Three-- Level Fusion in Patients Undergoing Multilevel Lumbar Decompression: Relative Perioperative Risks and Five-year Revisions.

Retrospective cohort study. To assess relative odds of perioperative complications, readmissions, and five-year survival to reoperation for three-level lumbar decompression patients who undergo three-level fusion relative to one-level fusion. Patients undergoing multilevel lumbar decompression may be indicated for fusion at one or more levels. The question of fusing only one level with indications such as spondylolisthesis or fusing all levels decompressed is of clinical interest in both the short and longer term. Patients undergoing three-level lumbar decompression were extracted from the PearlDiver M165Orto database. The subset of these patients undergoing concomitant three-level and one-level lumbar fusion were identified and matched 1:1 based on patient age, sex, and Elixhauser Comorbidity Index (ECI) scores. The incidence and odds of 90-day postoperative adverse events were compared between the two groups by multivariable analysis, and comparative five-year survival to lumbar spinal reoperation was determined. After matching, 28,276 patients were identified as undergoing three-level lumbar decompression with three-level fusion and the same for those undergoing three-level decompression with one-level fusion. Controlling for patient age, sex, and ECI, three-level fusion patients had significantly greater odds ratio (OR) of many 90-day adverse events and aggregated any (OR 1.42), serious (OR 1.44), and minor (OR 1.42) adverse events, as well as readmissions (OR 1.51) (P<0.0001 for all). Five-year survival to reoperation was significantly lower for those undergoing three-level decompression with three-level fusion (P<0.0001). Three-level lumbar decompression patients who underwent three-level fusion were found to be at significantly greater odds of 90-day postoperative adverse events, readmissions, and five-year reoperations relative to those undergoing one-level fusion. The current data support the concept of limiting fusion to the levels with specific indications in the setting of multi-level lumbar decompressions and not needing to match the decompression and fusion levels.

Revision Surgery after Single Level Anterior Cervical Discectomy and Fusion With Plate vs Stand-Alone Cage over 2 to 5 Year Follow-Up.

retrospective study. To investigate the incidence of all-cause revision surgery between plated vs stand-alone cage constructs for single level ACDF. We retrospectively analyzed a commercial insurance claims database. Patients 18-65years-old were included if they underwent single-level inpatient ACDF (defined with CPT codes) from 2010 - 2018, with a minimum of 2-year continuous insurance enrollment. The primary independent variable was the use of anterior plating vs zero profile device or stand-alone cage. Synthetic (ie, metal, PEEK, etc.) vs allograft interbody was a secondary independent variable. The primary outcome variable was revision cervical arthrodesis after the index operation. In total, 21092 patients undergoing single-level inpatient ACDF were included. 10.0% received a stand-alone cage during the index operation. Mean follow-up duration was 4.5years. Revision arthrodesis occurred in 8.2% of patients overall, at a mean of 2.4years after the index surgery. Patients with anterior plating had a lower rate of all-cause revision surgery in unadjusted (overall rate 8.1% vs 9.6%, P = 0.0185) and adjusted analysis (OR 0.78, P = 0.0016) vs stand-alone cages. Patients with stand-alone cages had higher rates of revision with a posterior approach than did patients with plated constructs. In sub-analysis, the combination of a stand-alone interbody device with an allograft had significantly higher odds of revision than other combinations of devices. Among commercially insured patients ≤65years-old undergoing single-level ACDF, anterior plating was associated with a reduced incidence of revision surgery compared to stand-alone cages within the follow up period of our study.

Mismatch Between Pelvic Incidence and Lumbar Lordosis After Personalized Interbody Fusion: The Importance of Preoperative Planning and Alignment in Degenerative Spine Diseases.

Emerging data have highlighted the significance of planning and aligning total and segmental lumbar lordosis with pelvic morphology when performing short-segment fusion with the goal of reducing the risk of adjacent segment disease while also decreasing spine-related disability. This study evaluates the impact of personalized interbody implants in restoring pelvic incidence-lumbar lordosis (PI-LL) mismatch compared with a similar study using stock interbody implants. This multicenter retrospective analysis assessed radiographic pre- and postoperative spinopelvic alignment (PI-LL) in patients who underwent 1- or 2-level lumbar fusions with personalized interbody implants for degenerative (nondeformity) indications. The aim was to assess the incidence of malalignment (PI-LL ≥ 10°) both before and after fusion surgery and to determine the rate of alignment preservation and/or correction in this population. There were 135 patients included in this study. Of 83 patients who were aligned preoperatively, alignment was preserved in 76 (91.6%) and worsened in 7 (8.4%). Among the 52 preoperatively malaligned patients, alignment was restored in 23 (44.2%), and 29 (55.8%) were not fully corrected. Among patients who were preoperatively aligned, there was no statistically significant difference in either the "preserved" or "worsened" groups between stock devices and personalized interbody devices. In contrast, among patients who were preoperatively malaligned, there was a statistically significant increase in the "restored" group (P = 0.046) and a statistically significant decrease in the "worsened" groups in patients with personalized interbodies compared with historical stock device data (P < 0.05). Compared with a historical cohort with stock implants, personalized interbody implants in short-segment fusions have shown a statistically significant improvement in restoring patients to normative PI-LL. Using 3-dimensional preoperative planning combined with personalized implants provides an important tool for planning and achieving improvement in spinopelvic parameters.

Risk factors for allogeneic red blood cell transfusion in adult spinal deformity surgery.

Retrospective study. To investigate the risk factors for allogeneic red blood cell (RBC) transfusion in adult spinal deformity (ASD) surgery. Studies have not thoroughly explored the roles of intraoperative hypothermia, autologous blood donation, and hemostatic agent administration, which would provide a better understanding of the risk for perioperative RBC transfusion in ASD surgery. The medical records of 151 patients with ASD who underwent correction surgery between 2012 and 2021 were retrospectively reviewed. Estimated blood loss and perioperative allogeneic transfusion were examined. Patients were categorized into two groups based on whether they received perioperative allogeneic blood transfusion. Logistic regression analysis was employed to investigate the effect of age, sex, blood type, body mass index, American Society of Anesthesiologists' physical status, preoperative hemoglobin level, autologous blood donation, global spine alignment parameters, preoperative use of anticoagulants or antiplatelet medicine and nonsteroidal anti-inflammatory drugs, number of instrumented fusion levels, total operative duration, three-column osteotomy, lateral interbody fusion, pelvic fixation, intraoperative hypothermia, use of gelatin-thrombin based hemostatic agents, and intraoperative tranexamic acid (TXA) with simultaneous exposure by two attending surgeons. The estimated blood loss was 994.2±754.5 mL, and 71 patients (47.0%) received allogeneic blood transfusion. In the logistic regression analysis, the absence of intraoperative TXA use and simultaneous exposure (odds ratio [OR], 26.3; 95% confidence interval [CI], 7.6-90.9; p<0.001), lack of autologous blood donation (OR, 21.2; 95% CI, 4.4-100.0; p<0.001), and prolonged operative duration (OR, 1.6; 95% CI, 1.3-1.9; p<0.001) were significant independent factors for perioperative allogeneic blood transfusion in ASD surgery. Autologous blood storage, intraoperative TXA administration, and simultaneous exposure should be considered to minimize perioperative allogeneic blood transfusion in ASD surgery, particularly in patients with anticipated lengthy surgeries.

Prevertebral Soft-tissue Swelling Following One-level Anterior Cervical Discectomy and Fusion: An Analysis Based on Surgical Level.

The purposes of this study were to identify the primary level at which PSTS occurs following one level anterior cervical discectomy and fusion (ACDF) based on surgical level, and to quantify the degree to which it occurs. Although prevertebral tissue swelling (PSTS) peaks at day 2 or 3 after ACDF, with swelling noted to be prominent at levels C2-4, the way in which the features of PSTS vary according to surgical level has not been examined. 37 patients who underwent one-level ACDF were reviewed and classified into retropharyngeal and retrotracheal group based on surgical level. PSTS occurring at C2-C6 and the width of airway (WA) at C2-C4 was assessed using plain radiographs before surgery and at 1, 3, 5, and 7 days postoperatively. The retropharyngeal group comprised 10 patients while the retrotracheal group comprised 27 patients. Retropharyngeal group had the most severe PSTS on day 3 after surgery. C4 showed PSTS peaked on day 3, with a value of 3.26 times the preoperative prevertebral tissue thickness. WA at C4 was narrowest on day 1, with a value of 0.74 times and remained narrow until day 3. The retrotracheal group showed the most severe PSTS on day 1 at level C3:2.81 times. WA at C4 was narrowest on day 1 with a value of 0.78 times and increased thereafter. PSTS following one-level ACDF for both retropharyngeal and retrotracheal lesions was greatest at the C3 and C4 levels, with peaks on the third day after operation for the former, and the first day for the latter. WA at C4 was narrowest from day 1 in both groups. In the retrophyaryngeal group, narrowing remained until day 3.

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 48h 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.

Preoperative Planning of Lumbar Lordosis for Adult Degenerative Scoliosis Surgery in the Chinese Population

Pelvic incidence minus lumbar lordosis mismatch (PI-LL) is directly related to poor quality of life in adult degenerative scoliosis (ADS) patients. The purpose of the study was to determine the most appropriate postoperative PI-LL value for patients with ADS. The medical records of patients with ADS in our department were retrospectively collected. The data included age, sex, body mass index, age-adjusted Charlson comorbidity index, osteopenia, length of hospital stay, operative duration, estimated blood loss, American Society of Anesthesiologists score, number of fusion levels, lumbar lordosis, sagittal vertical axis, pelvic incidence, PI-LL, Scoliosis Research Society-22 score, Oswestry Disability Index score, and mechanical complications. A total of 316 patients were enrolled. PI-LL, lumbar lordosis, sagittal vertical axis, Scoliosis Research Society-22 score, Oswestry Disability Index score at the time of last follow-up were 20.7 ± 8.5°, 23.4 ± 14.1°, 4.0 ± 2.1cm, 3.7 ± 0.9, and 18.1 ± 5.5, respectively. In terms of mechanical complications, 88 patients (27.8%), 34 patients (10.8%), and 19 patients (6.0%) had proximal junctional kyphosis, distal junctional kyphosis, and implant-related complications, respectively. In the fully adjusted model, compared with 0 grade PI-LL group and++ grade PI-LL group,+ grade PI-LL group had the best clinical outcomes and the fewest mechanical complications. The stability of these conclusions was verified in sensitivity analyses. Optimal PI-LL value should be 10°-20° after corrective surgery in patients with ADS, which is associated with excellent clinical outcomes and lower complication rates. Previous criteria may be at risk of overcorrection, which may lead to proximal junctional kyphosis.

Cage Obliquity in Oblique Lumbar Interbody Fusion-How Common Is It and What Are the Effects on Fusion Rates, Subsidence, and Sagittal Alignment? A Computed Tomography-Based Analysis.

Oblique lumbar interbody fusion (OLIF) through a prepsoas approach was identified as an alternative to alleviate complications associated with direct lateral interbody fusion. Cage placement is known to influence cage subsidence and fusion rates due to suboptimal biomechanics. There are limited studies exploring cage obliquity as a potential factor influencing fusion outcomes. Hence, our objective was to assess the effects of cage obliquity and position on fusion rates, subsidence, and sagittal alignment in patients who underwent OLIF. Patients who underwent OLIF for levels L1 to L5 in our center, performed by a single surgeon and with a minimum of 12 months of follow-up, were included in the study. Cage obliquity and sagittal placement were measured, and their correlation with fusion, subsidence, and sagittal alignment correction was assessed. Fusion and subsidence were evaluated using the Bridwell Criteria and Marchi Criteria, respectively. Among the included patients (age, 67.5 ± 7.93 years; 16 men and 37 women), 97 fusion levels were studied. The mean cage obliquity was 4.2° ± 2.8°. Ninety-six levels (99.0%) were considered to have achieved fusion with a Bridwell score of 1 or 2. Eighty-one (83.5%), 14 (14.4%), and 2 (2.06%) operated levels had a Marchi score of 0, 1, and 2, respectively. A Marchi grade of 1 or higher was considered indicative of significant subsidence. There was good improvement in both the segmental lordosis angle (4.2° ± 5.7°; P < 0.0001) and disc height (4.5 ± 3.8 mm; P < 0.0001). Cage placement did not have any statistical correlation with fusion rates, subsidence, or sagittal alignment. Our results indicate that OLIF facilitates appropriate cage placement with only a minor degree of cage obliquity, typically less than 20°. This minor obliquity does not lead to lower fusion rates, increased subsidence, or sagittal malalignment. Despite subsidence being common, the majority of these cases resulted in complete fusion.

Posterior Spinal Fusion for Severe Kyphosis in a Child with Gaucher Disease: A Case Report and Review of the Literature

Background: Skeleton involvement is one of the most significant aspects of Gaucher disease (GD). However, the treatment for spinal involvement in GD among patients undergoing enzyme replacement therapy (ERT) is poorly characterized. We present a case of progressive kyphotic spinal deformity in a young child caused by vertebral involvement, which was managed by posterior spinal fusion without anterior spinal release under ERT. Case presentation: This is a retrospective study. A 10-year-old boy presenting with progression kyphosis (thoracic kyphotic angle of 113°) associated with type-IIIb GD had undergone posterior spinal fusion with segmental pedicle screw fixation (from T6-L3) and Ponte osteotomy. The patient went back to school without further brace protection. Proximal junctional kyphosis (PJK) was observed at 4 months postoperatively. Revision surgery was performed to prevent neurological impairment. Additional posterior spinal fusion from T2–T6 and decompressive laminectomy were performed during the revision surgery. A 2-year follow-up showed no recurrence of PJK and solid fusion was achieved in the patient under ERT and brace protection. Conclusions: Posterior spinal fusion without anterior spinal release is a good treatment option for severe spinal deformity in patients with GD. However, the fusion level and reinforced fixation require careful consideration. Revision surgery and brace protection is needed as long as PJK is observed.

Comparative study of low-density versus high-density pedicular screw implantations in management of adolescent idiopathic scoliosis: a randomized clinical trial

BackgroundA number of studies have yielded disparate findings regarding the relationship between implant density and curve correction in adolescent idiopathic scoliosis (AIS) surgery. This study compared the efficacy and safety of low-density (LD) versus high-density (HD) pedicular screw implants in the correction of deformity in AIS regarding clinical, radiological, and quality of life outcomes. MethodsThis study was a single-blind, parallel, randomized trial that enrolled 20 adolescent patients with idiopathic scoliosis scheduled for posterior spinal fusion surgery with all pedicle screw constructs. Patients were randomized into two groups of 10 patients each. The LD group included patients in whom the number of screws per fused spinal level had a density of 1.5 or less, while the HD group had a density greater than 1.5. The primary outcomes were the radiological findings of curve correction. The secondary outcomes included the correlation between implant density and curve correction, the amount of blood loss, operation time, number of screws, fusion level, hospital stay duration, and quality of life assessed by the Scoliosis Research Society 22r questionnaire. ResultsRadiologically, the postoperative main curves Cobb angles and their changes were comparable between both approaches without statistical correlation with the implant density (p˃0.05). The LD approach significantly shortened the operative time (p=0.015), number of screws (p=0.011), implant density (p<0.001), and hospital stay (p<0.001). However, quality of life scores before surgery and at final follow-up did not differ between the two techniques (p˃0.05). ConclusionsThe use of a low-density approach is an effective and safe methodology for attaining satisfactory deformity correction in AIS patients. Furthermore, this approach confers the additional advantage of reduced operative time, number of screws, implant density, and hospital stay in comparison to the high-density approach.Trial registration Pan African Clinical Trial Registry, PACTR202404611444119. Registered 28 March 2024-Retrospectively registered, https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=29382