(3+2) Annulation of 4-Acetoxy Allenoate with Aldimine Enabled by AgF-Assisted P(III)/P(V) Catalysis.

A phosphine-catalyzed (3+2) annulation of 4-acetoxy allenoate and aldimine with the assistance of AgF is described. The success of this reaction hinges on the metathesis between the enolate-phosphonium zwitterion and AgF, leading to a key intermediate comprising of silver enolate and a fluorophosphorane P(V)-moiety. The former is able to undergo a Mannich reaction with aldimine, whereas the latter initiates a cascade sequence of AcO-elimination/aza-addition, thus furnishing the P(III)/P(V) catalysis. By taking advantage of the silver enolate, a preliminary attempt at an asymmetric variant was conducted with the combination of an achiral phosphine catalyst and a chiral bis(oxazolinyl)pyridine ligand (PyBox), giving moderate enantioselectivity.

Domino Sequences Involving Stereoselective Hydrazone-Type Heck Reaction and Denitrogenative [1,5]-Sigmatropic Rearrangement.

Although the Heck reactions of alkene partners with various electrophiles have achieved great success, the variant focused on carbon═heteroatom counterparts still remains elusive. Herein, we report a Pd(0)-catalyzed asymmetric intramolecular hydrazone-type Heck reaction of N-[(Z)-3-iodoallyl]-aminoacetaldehyde and hydrazine hydrate (NH2NH2-H2O), wherein the required hydrazone is in situ generated via an acid-promoted condensation. A key strategic advantage of this Heck paradigm is that the resultant Heck product allylic diazene rapidly undergoes stereospecific denitrogenative [1,5]-sigmatropic rearrangement, eventually furnishing a domino sequence toward 3-substituted tetrahydropyridine (THP) with high enantioselectivity. The substrate-induced diastereoselective version has also been realized, exclusively giving cis-2,5-disubstituted THPs. The utility of this sequence is demonstrated by the formal synthesis of multiple valuable bioactive targets, including 3-ethylindoloquinolizine, preclamol, and niraparib.

The Reliability of Computer-Assisted Three-Dimensional Surgical Simulation of Posterior Osteotomies in Thoracolumbar Kyphosis Secondary to Ankylosing Spondylitis Patients.

Objectives: The study was aimed at investigating the reliability of computer-assisted three-dimensional surgical simulation (CA3DSS) of posterior osteotomies in thoracolumbar kyphosis secondary to ankylosing spondylitis (TLKAS) patients. Methods: Eligible TLKAS patients who underwent posterior correction surgery with posterior osteotomies were consecutively included. Simulated posterior osteotomies were performed in Mimics and 3-Matic Medical software. Coronal and sagittal angle and alignment parameters were measured in preoperative full-length X-ray, preoperative original 3D spine (Pre-OS), simulated 3D spine (SS), and postoperative original 3D spine (Post-OS). Reliability was tested by both intraclass correlation coefficients (ICCs) and Bland-Altman analysis. Results: A total of 30 TLKAS patients were included. Excellent consistency of radiological parameters was shown between preoperative X-ray and Pre-OS model. In SS and Post-OS models, excellent reliabilities were shown in global kyphosis (ICC 0.832, 95% CI 0.677-0.916), thoracic kyphosis (ICC 0.773, 95% CI 0.577-0.885), and lumbar lordosis (ICC 0.896, 95% CI 0.794-0.949) and good reliabilities were exhibited in the main curve (ICC 0.680, 95% CI 0.428-0.834) and sagittal vertical axis (ICC 0.619, 95% CI 0.338-0.798). ICCs of correction angle achieved by pedicle subtraction osteotomy (PSO) was 0.754 (95% CI 0.487-0.892), and that of posterior column osteotomies (PCO) was 0.703 (95% CI 0.511-0.829). Bland-Altman analysis also showed good agreement for both Cobb angle and distance measurements in Pre-OS and SS models, and good reliabilities were shown in PCO and PSO in real spine and SS models. Conclusions: CA3DSS can provide an accurate measurement, and it is a reliable and effective method to conduct proper simulation for correction surgery with posterior osteotomies in TLKAS patients. This trial is registered with Chinese Clinical Trial Registry ChiCTR2100053808.

The feasibility and efficacy of computer-assisted screw inserting planning in the surgical treatment for severe spinal deformity: a prospective study.

BACKGROUND: The objective of the study was to explore the feasibility and efficacy of computer-assisted screw inserting planning (CASIP) in the surgical treatment for severe spinal deformity. METHODS: A total of 50 patients participated in this prospective cohort study. 25 patients were allocated into CASIP group and 25 patients were in Non-CASIP group. The demographic data, radiological spinal parameters were documented and analyzed. Each pedicle screw insertion was classified as satisfactory insertion or unsatisfactory insertion based on Gertzbein-Robbins classification. The primary outcome was the accuracy of pedicle screw placement. The secondary outcomes were the rate of puncturing screws, estimated blood loss, surgical time, correction rate and other radiological parameters. RESULTS: A total of 45 eligible patients completed the study. 20 patients were in CASIP group and 25 patients were in Non- CASIP group. The accuracy of pedicle screw placement in CASIP Group and Non-CASIP Group were (92.0 ± 5.5) % and (82.6 ± 8.3) % (P < 0.05), and the rate of puncturing screws were (0 (0-0)) % and (0 (0-6.25)) % (P < 0.05). The median surgical time were 280.0 (IQR: 260.0-300.0) min and 310 (IQR: 267.5-390.0) min in two group and showed significant statistic difference (P < 0.05). CONCLUSIONS: CASIP has good feasibility and can gain a more accurate and reliable instruments fixation, with which spine surgeons can make a detailed and personalized screw planning preoperatively to achieve satisfying screw placement.

Cortical screw placement with a spinous process clamp guide: a cadaver study accessing accuracy.

BACKGROUND AND OBJECTIVE: The Cortical Bone Trajectory (CBT) technique provides an alternative method for fixation in the lumbar spine in patients with osteoporosis. An accuracy CBT screw placement could improve mechanical stability and reduce complication rates. PURPOSE: The purpose of this study is to explore the accuracy of cortical screw placement with the application of implanted spinous process clip (SPC) guide. METHODS AND MATERIALS: Four lumbar specimens with T12-S1 were used to access the accuracy of the cortical screw. The SPC-guided planning screws were compared to the actual inserted screws by superimposing the vertebrae and screws preoperative and postoperative CT scans. According to preoperative planning, the SPC guide was adjusted to the appropriate posture to allow the K-wire drilling along the planned trajectory. Pre and postoperative 3D-CT reconstructions was used to evaluate the screw accuracy according to Gertzbein and Robbins classification. Intraclass correlation coefficients (ICCs) and Bland-Altman plots were used to examine SPC-guided agreements for CBT screw placement. RESULTS: A total of 48 screws were documented in the study. Clinically acceptable trajectory (grades A and B) was accessed in 100% of 48 screws in the planning screws group, and 93.8% of 48 screws in the inserted screws group (p = 0.242). The incidence of proximal facet joint violation (FJV) in the planning screws group (2.1%) was comparable to the inserted screws group (6.3%) (p = 0.617). The lateral angle and cranial angle of the planned screws (9.2 ± 1.8° and 22.8 ± 5.6°) were similar to inserted screws (9.1 ± 1.7° and 23.0 ± 5.1°, p = 0.662 and p = 0.760). Reliability evaluated by intraclass correlation coefficients and Bland-Altman showed good consistency in cranial angle and excellent results in lateral angle and distance of screw tip. CONCLUSIONS: Compared with preoperative planning screws and the actually inserted screws, the SPC guide could achieve reliable execution for cortical screw placement.

Cu(OAc)2-Promoted Oxidative Cross-Dehydrogenative Coupling Reaction of α-Acylmethyl Malonates with Indole Derivatives to Access 3-Functionalized Indoles and Polycyclic Indoles.

A Cu(OAc)2-promoted oxidative cross-dehydrogenative coupling reaction of α-acylmethyl malonates with indole derivatives was developed. In the case of indoles, the regioselective coupling products were formed through a sequential dehydrogenation-addition-dehydrogenation process. When a second nucleophilic center was located in the 2-position of indoles, further successive nucleophilic cyclization occurred to give polycyclic indole derivatives. The Cu(OAc)2 was proved to act as not only an oxidant but also a catalyst.

Selective hemivertebrae resection in a congenital scoliosis patient with multiple hemivertebrae deformities.

PURPOSE: To report the surgical experience of selective hemivertebrae resection for a case of congenital scoliosis with multiple hemivertebrae deformities. METHODS: A 14-year-old male presented with progressive rib hump, tilted torso and spine deformity was admitted in our department. No abnormalities were detected in neurological examination and the comprehensive imaging study demonstrated congenital scoliosis of multiple hemivertebrae in T5, T10, L1 and L3. Treatment of the patient commenced with a 10-day skin traction therapy prior to the surgery. Selective resection of hemivertebrae in T5 and L1 was performed with segmental fusion from T3 to L2. RESULTS: After surgical procedure, the patient achieved a good coronal and sagittal balance along with a good correction of the curve. 18-month postoperative follow-up showed no evidence of significant loss of correction. No device-related complication such as implant loosening or failure or neurologic complication occurred during the follow-up. Besides, patient's shoulder balance was further improved and coronal balance was maintained in a normal range. CONCLUSION: Many factors have to be considered in the clinical decision-making of congenital scoliosis with multiple hemivertebrae deformities patients. Much emphasis in this regard is laid on the type and location of the hemivertebrae as well as the patient's age. Selective hemivertebrae resection may be more suitable for such patients.

Adjacent segment degeneration after lumbar spinal fusion compared with motion-preservation procedures: a meta-analysis.

PURPOSE: This meta-analysis aimed to evaluate the efficacy of motion-preservation procedures to prevent the adjacent segment degeneration (ASDeg) or adjacent segment disease (ASDis) compared with fusion in lumbar spine. METHODS: PubMed, Embase and the Cochrane Library were comprehensively searched and a meta-analysis was performed of all randomized controlled trials and well designed prospective or retrospective comparative cohort studies assessing the lumbar fusion and motion-preservation procedures. We compared the ASDeg and ASDis rate, reoperation rate, operation time, blood loss, length of hospital stay, visual analogue scale (VAS) and oswestry disability index (ODI) improvement of the two procedures. RESULTS: A total of 15 studies consisting of 1474 patients were included in this study. The meta-analysis indicated that the prevalence of ASDeg, ASDis and reoperation rate on the adjacent level were lower in motion-preservation procedures group than in the fusion group (P = 0.001; P = 0.0004; P < 0.0001). Moreover, shorter length of hospital stay was found in motion-preservation procedures group (P < 0.0001). No difference was found in terms of operation time (P = 0.57), blood loss (P = 0.27), VAS (P = 0.76) and ODI improvement (P = 0.71) between the two groups. CONCLUSIONS: The present evidences indicated that the motion-preservation procedures had an advantage on reducing the prevalence of ASDeg, ASDis and the reoperation rate due to the adjacent segment degeneration compared with the lumbar fusion. And the clinical outcomes of the two procedures are similar.

Anterior cervical discectomy and fusion may be more effective than anterior cervical corpectomy and fusion for the treatment of cervical spondylotic myelopathy.

BACKGROUND: This meta-analysis explored the efficacy and safety of anterior cervical corpectomy and fusion (ACCF) comparing to anterior cervical discectomy and fusion (ACDF) in treating cervical spondylotic myelopathy (CSM) patients. METHODS: Several electronic databases were searched combined with manually searching. Thirteen randomized controlled studies were enrolled with 1,062 CSM patients, including 468 patients and 594 patients in the in the ACCF and ACDF group, respectively. The meta-analysis was then performed using the STATA 12.0 software. Crude standard mean difference (SMD) or odds ratio (OR) with their 95% confidence intervals (CI) were calculated. RESULTS: Our meta-analysis results revealed that CSM patients in ACDF group showed less blood loss than those in ACCF group (SMD = 1.21, 95% CI = 1.03 ~ 1.39, P < 0.001). The operation time of CSM patients in the ACDF group was also obviously shorter than those in ACCF group (SMD = 0.40, 95% CI = 0.23 ~ 0.57, P < 0.001). Furthermore, CSM patients in ACDF group had shorter hospital time than those in ACCF group (SMD = 0.45, 95% CI = 0.21 ~ 0.69, P < 0.001). CONCLUSION: Our findings provide empirical evidence that ACDF may be more effective than ACCF for CSM treatment.

[The optimal insertion position of the lumbar interspinous dynamic stabilization device (Coflex): a biomechanical evaluation].

OBJECTIVE: To evaluate the optimal insertion position of the Coflex lumbar interspinous dynamic stabilization device. METHODS: Six fresh adult human cadaveric lumbar spine specimens (L1-L5) were mounted in a materials testing machine by embedding to clamps with L1 and L5 vertebrae. L3-4 motion segment of each specimen was operated by selective decompression and Coflex interspinous device insertion. The L3 and L4 vertebrae was inserted one needle attached with four marker points respectively, which were used to record the range of motion (ROM). Each lumbar spine specimen was tested according to the loading sequence at 5 groups: intact (keeping lumbar ligamenta and facet joints intact) group, partial destabilized (resection of L3-4 interspinous ligamenta, ligamentum flavum, facet capsule, and bilateral resection 50% of L3 inferior facets) group, 10 mm insertion (distance between apex of U-shaped Coflex and dural sac was 10 mm)group, 5 mm insertion (distance was 5 mm)group, and 0 mm insertion (distance was 0 mm)group. Each lumbar spine specimen was tested repeatedly 3 times according to a loading sequence consisting of flexion, extension, left/right lateral bending, left/right axial rotation, loaded with pure moments of 8 N·m, and was recorded the ROM of operative segment at the third time. ROM of 5 groups in 6 directions respectively were analyzed with one-way ANOVA test and multiple comparisons were based on LSD method. RESULTS: The means ROM of 5 groups were not all equal in flexion, extension, left/right lateral bending, left/right axial rotation (F = 8.472, 18.301, 7.700, 12.473, 16.809, 6.624; all P < 0.01). The 10 mm insertion group had significant high ROM in 6 directions than the intact group (t = 3.80, 3.82, 4.49, 5.60, 4.96, 2.98, all P < 0.01), but it was no difference comparing with the partial destabilized group (P > 0.05). The ROM of the 5 mm and 0 mm insertion group were no significant differences comparing with the intact group in flexion, extension, left/right axial rotation (P > 0.05), but it were significant differences comparing with the partial destabilized group in the same directions (5 mm insertion group: t = 3.19, 6.34, 5.26, 3.43, all P < 0.01; 0 mm insertion group: t = 4.21, 6.68, 5.81, 3.72, all P < 0.01). There were significant differences in the ROM of left/right lateral bending between the 5mm/0mm insertion groups and the intact group (5 mm insertion group: t = 3.71 and 5.22, all P < 0.01; 0 mm insertion group: t = 3.44 and 4.95, all P < 0.01), but there were no differences comparing with the partial destabilized group in the same directions (P > 0.05). CONCLUSIONS: The insertion of Coflex interspinous dynamic stabilization device can maintain the stability of a partially destabilized specimen back to an intact one in flexion, extension and axial rotation when distance between apex of U-shaped Coflex and dural sac was ≤ 5 mm, but can't return the stability in lateral bending. The Coflex can't return the stability of a partially destabilized specimen back to an intact one in 6 directions when distance between apex of U-shaped Coflex and dural sac was ≥ 10 mm.

Transition from Kwon [4+2]- to [3+2]-cycloaddition enabled by AgF-assisted phosphine catalysis.

Phosphine catalysis generally relies on the potential of carbanion-phosphonium zwitterions that are generated via nucleophilic addition of phosphine catalyst to electrophilic reactants. Consequently, structural modification of zwitterions using distinct electrophilic reactants has emerged as a prominent strategy to enhance catalysis diversity. Herein, we present an alternative strategy that utilizes AgF additive to expand phosphine catalysis. We find that AgF can readily transform the canonical carbanion-phosphonium zwitterion into silver enolate-fluorophosphorane intermediate, eventually furnishing a P(III)/P(V) catalytic cycle. This strategy has been successfully applied to the phosphine-catalyzed reaction of 2-substituted allenoate and imine, resulting in the transition from Kwon [4 + 2] cycloaddition to [3 + 2] cycloaddition. This [3 + 2] cycloaddition features remarkable diastereoselectivity, high yield, and broad substrate scope. Experimental and computational studies have validated the proposed mechanism. Given the prevalence of carbanion-phosphonium zwitterions in phosphine catalysis, this AgF-assisted strategy is believed to hold significant potential for advancing P(III)/P(V) catalysis.

Precise execution of personalized surgical planning using three-dimensional printed guide template in severe and complex adult spinal deformity patients requiring three-column osteotomy: a retrospective, comparative matched-cohort study.

BACKGROUND: The surgical treatment of severe and complex adult spinal deformity (ASD) commonly required three-column osteotomy (3-CO), which was technically demanding with high risk of neurological deficit. Personalized three dimensional (3D)-printed guide template based on preoperative planning has been gradually applied in 3-CO procedure. The purpose of this study was to compare the efficacy, safety, and precision of 3D-printed osteotomy guide template and free-hand technique in the treatment of severe and complex ASD patients requiring 3-CO. METHODS: This was a single-centre retrospective comparative cohort study of patients with severe and complex ASD (Cobb angle of scoliosis > 80° with flexibility < 25% or focal kyphosis > 90°) who underwent posterior spinal fusion and 3-CO between January 2020 to January 2023, with a minimum 12 months follow-up. Personalized computer-assisted three-dimensional osteotomy simulation was performed for all recruited patients, who were further divided into template and non-template groups based on the application of 3D-printed osteotomy guide template according to the surgical planning. Patients in the two groups were age- and gender- propensity-matched. The radiographic parameters, postoperative neurological deficit, and precision of osteotomy execution were compared between groups. RESULTS: A total of 40 patients (age 36.53 ± 11.98 years) were retrospectively recruited, with 20 patients in each group. The preoperative focal kyphosis (FK) was 92.72° ± 36.77° in the template group and 93.47° ± 33.91° in the non-template group, with a main curve Cobb angle of 63.35° (15.00°, 92.25°) and 64.00° (20.25°, 99.20°), respectively. Following the correction surgery, there were no significant differences in postoperative FK, postoperative main curve Cobb angle, correction rate of FK (54.20% vs. 51.94%, P = 0.738), and correction rate of main curve Cobb angle (72.41% vs. 61.33%, P = 0.101) between the groups. However, the match ratio of execution to simulation osteotomy angle was significantly greater in the template group than the non-template group (coronal: 89.90% vs. 74.50%, P < 0.001; sagittal: 90.45% vs. 80.35%, P < 0.001). The operating time (ORT) was significantly shorter (359.25 ± 57.79 min vs. 398.90 ± 59.48 min, P = 0.039) and the incidence of postoperative neurological deficit (5.0% vs. 35.0%, P = 0.018) was significantly lower in the template group than the non-template group. CONCLUSION: Performing 3-CO with the assistance of personalized 3D-printed guide template could increase the precision of execution, decrease the risk of postoperative neurological deficit, and shorten the ORT in the correction surgery for severe and complex ASD. The personalized osteotomy guide had the advantages of 3D insight of the case-specific anatomy, identification of osteotomy location, and translation of the surgical planning or simulation to the real surgical site.

Current state and influencing factors in airbag management among emergency department nurses: A multicenter study.

BACKGROUND: The emergency department (ED) plays a critical role in establishing artificial airways and implementing mechanical ventilation. Managing airbags in the ED presents a prime opportunity to mitigate the risk of ventilator-associated pneumonia. Nonetheless, existing research has largely overlooked the understanding, beliefs, and practical dimensions of airway airbag management among ED nurses, with a predominant focus on intensive care unit nurses. AIM: To investigate the current status of ED nurses' knowledge, beliefs, and practical behaviors in airway airbag management and their influencing factors. METHODS: A survey was conducted from July 10th to August 10th, 2023, using convenience sampling on 520 ED nurses from 15 tertiary hospitals and 5 sary hospitals in Shanghai. Pathway analysis was utilized to analyze the influencing factors. RESULTS: The scores for ED nurses' airway airbag management knowledge were 60.26 ± 23.00, belief was 88.65 ± 13.36, and behavior was 75.10 ± 19.84. The main influencing factors of airbag management knowledge included participation in specialized nurse or mechanical ventilation training, department, and work experience in the department. Influencing factors of airbag management belief comprised knowledge, department, and participation in specialized nurse or mechanical ventilation training. Primary influencing factors of airbag management behavior included knowledge, belief, department, participation in specialized nurse or mechanical ventilation training, and professional title. The belief in airbag management among ED nurses acted as a partial mediator between knowledge and behavior, with a total effect value of 0.513, and an indirect effect of 0.085, constituting 16.6% of the total effect. CONCLUSION: ED nurses exhibit a positive attitude toward airbag management with relatively standardized practices, yet there remains room for improvement in their knowledge levels. Nursing managers should implement interventions tailored to the characteristics of ED nurses' airbag management knowledge, beliefs, and practices to enhance their airbag management proficiency.

Preceding neurosurgery is not needed for presumed adolescent idiopathic scoliosis with syringomyelia: a 10-year longitudinal comparative study.

Background: One-stage scoliosis correction surgery is safe for adolescent idiopathic scoliosis (AIS), but it is not yet known whether it is safe for presumed AIS (PAIS). This study sought to investigate the safety and efficacy of one-stage scoliosis correction surgery for PAIS associated with syringomyelia from multiple perspectives by conducting an analysis of 10-year consecutive cases. Methods: A retrospective study of all consecutive cases of patients diagnosed with PAIS associated with syringomyelia or AIS from January 2011 to January 2020 was performed. The main radiographic parameters and clinical function scores before, immediately after, and at the last follow-up were collected or measured. Three-dimensional (3D) models of spinal canal length were generated, refined, measured, and compared between the PAIS and AIS groups. Results: In total, 318 patients with AIS and 47 patients with PAIS associated with syringomyelia were included in the study. There were no significant differences between the two groups in terms of changes in the Cobb angle of the main curve (MC), thoracic kyphosis (TK), coronal balance (CB), sagittal vertical axis (SVA), Oswestry disability index (ODI), Scoliosis Research Society-22 (SRS-22) score, cervical and thoracolumbar spinal canal length, and whole spinal canal length before and after the surgery (P>0.05). The changes in the thoracolumbar and whole spinal canal length were significantly positively correlated with the improvement rate of the MC (P<0.05), but were not significantly correlated with the improvement rate of TK, the SRS-22 score, and the ODI (P>0.05). Conclusions: In relation to the main radiologic parameters, clinical function scores, and 3D biomechanics, one-stage posterior correction surgery was found to be safe and effective for patients with PAIS associated with syringomyelia.

Clinical Application of Personalized Digital Surgical Planning and Precise Execution for Severe and Complex Adult Spinal Deformity Correction Utilizing 3D Printing Techniques.

(1) Background: The three-dimensional printing (3DP) technique has been reported to be of great utility in spine surgery. The purpose of this study is to report the clinical application of personalized preoperative digital planning and a 3DP guidance template in the treatment of severe and complex adult spinal deformity. (2) Methods: eight adult patients with severe rigid kyphoscoliosis were given personalized surgical simulation based on the preoperative radiological data. Guidance templates for screw insertion and osteotomy were designed and manufactured according to the planning protocol and used during the correction surgery. The perioperative, and radiological parameters and complications, including surgery duration, estimated blood loss, pre- and post-operative cobb angle, trunk balance, and precision of osteotomy operation with screw implantation were collected retrospectively and analyzed to evaluate the clinical efficacy and safety of this technique. (3) Results: Of the eight patients, the primary pathology of scoliosis included two adult idiopathic scoliosis (ADIS), four congenital scoliosis (CS), one ankylosing spondylitis (AS), and one tuberculosis (TB). Two patients had a previous history of spinal surgery. Three pedicle subtraction osteotomies (PSOs) and five vertebral column resection (VCR) osteotomies were successfully performed with the application of the guide templates. The main cobb angle was corrected from 99.33° to 34.17°, and the kyphosis was corrected from 110.00° to 42.00°. The ratio of osteotomy execution and simulation was 97.02%. In the cohort, the average screw accuracy was 93.04%. (4) Conclusions: The clinical application of personalized digital surgical planning and precise execution via 3D printing guidance templates in the treatment of severe adult rigid deformity is feasible, effective, and easily generalizable. The preoperative osteotomy simulation was executed with high precision, utilizing personalized designed guidance templates. This technique can be used to reduce the surgical risk and difficulty of screw placement and high-level osteotomy.

Evaluation of Pulmonary Function After Halo-Pelvic Traction for Severe and Rigid Kyphoscoliosis Utilizing CT with 3D Reconstruction.

BACKGROUND: The purpose of the present study was to evaluate changes in pulmonary function, caused by preoperative halo-pelvic traction (HPT) for the treatment of extremely severe and rigid kyphoscoliosis, with use of 3-dimensional computed tomography (3D-CT) reconstruction and pulmonary function tests (PFTs). METHODS: Twenty-eight patients with severe and rigid scoliosis (Cobb angle, >100°) underwent preoperative HPT and staged posterior spinal fusion. CT, radiographic assessment, and PFT were performed during pre-traction and post-traction visits. The changes in total lung volume were evaluated with use of 3D-CT reconstruction, and the changes in pulmonary function were evaluated with PFTs at each time point. Differences were analyzed with use of 2-tailed paired Student t tests, and correlations were analyzed with use of Spearman rank tests. RESULTS: None of the patients had pulmonary complications during traction, and all radiographic spinal measurements improved significantly after HPT. The main Cobb angle was corrected from 143.30° ± 20.85° to 62.97° ± 10.83° between the pre-traction and post-traction evaluations. Additionally, the C7-S1 distance was lengthened from 280.48 ± 39.99 to 421.26 ± 32.08 mm between the pre-traction and post-traction evaluations. Furthermore, 3D lung reconstruction demonstrated a notable increase in total lung volume (TLV) (from 1.30 ± 0.25 to 1.83 ± 0.37 L) and maximum lung height (from 176.96 ± 27.44 to 202.31 ± 32.45 mm) between the pre-traction and post-traction evaluations. Moreover, PFTs showed that total lung capacity (TLC) improved between the pre-traction and post-traction evaluations (from 2.06 ± 0.32 to 2.98 ± 0.82 L) and that the changes in T1-T12 distance and maximum lung height were correlated with changes in TLV (p = 0.0288 and p = 0.0007, respectively). CONCLUSIONS: The application of HPT is a safe and effective method for improving pulmonary function in patients with extremely severe and rigid scoliosis before fusion surgery. The TLV as measured with CT-based reconstruction was greatly increased after HPT, mainly because of the changes in thoracic height. LEVEL OF EVIDENCE: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

High mobility group box 1 derived mainly from platelet microparticles exacerbates microvascular obstruction in no reflow.

INTRODUCTION: No reflow manifests coronary microvascular injury caused by continuous severe myocardial ischemia and reperfusion. Microvascular obstruction (MVO) has emerged as one fundamental mechanism of no reflow. However, the underlying pathophysiology remains incompletely defined. Herein, we explore the contribution of high mobility group box 1 (HMGB1), derived mainly from platelet microparticles exacerbating MVO in no reflow. MATERIALS AND METHODS: 44 STEMI patients undergoing successful primary percutaneous coronary intervention (PCI) were included in our study. Plasma HMGB1 levels in both the peripheral artery (PA) and infarct-related coronary artery (IRA) were measured by ELISA. Flow cytometry and confocal microscopy assessed the level of HMGB1+ platelet derived microparticles (PMPs) and platelet activation. Flow cytometry and western blot evaluated the procoagulant activity (PCA) and the release of inflammatory factors of human microvascular endothelial cells (HCEMCs). RESULTS: HMGB1 levels were significantly higher in the IRA in no-reflow patients. The levels of HMGB1+ PMPs were considerably higher in the IRA of patients with no reflow and were strongly associated with platelet activation. Moreover, our results show that HMGB1 interacts with human microvascular endothelial cells primarily through TLR4, inducing HCMEC proinflammatory, procoagulant phenotype, and monocyte recruitment, accelerating microvascular obstruction and facilitating the development of no reflow. CONCLUSION: Our results illustrate a novel mechanism by which HMGB1, derived mainly from PMPs, plays a crucial role in the pathogenesis of no-reflow, revealing a novel therapeutic target.

Accuracy of cortical bone trajectory screw fixation guided by spinous process clamp guide in lumbosacral vertebrae: A cadaver study.

BACKGROUND: The purpose of this study was to access the accuracy of cortical bone trajectory screw placement guided by spinous process clamp (SPC). METHODS: Eight formalin-treated cadaveric lumbar specimens with T12-S1 were used. A total of 96 screws were implanted in eight lumbar specimens. RESULTS: In the freehand (FH) group, clinically acceptable placement (grade A and B) was 40 screws (83.3%), meanwhile 44 screws (91.7%) in the SPC guide group (p = 0.217). The grade A screws in the SPC guide group were much more than that in the FH group (n = 40 vs. n = 31, p = 0.036). The misplacement screws (grade C, D, and E) and proximal facet joint violation (FJV) in the SPC group was comparable to the FH group. CONCLUSIONS: This cadaveric study demonstrate that implanting CBT screws guided by SPC guide was more accuracy and reduces severe deviations in important directions.

Postoperative complications following Schwab-grade-I versus Schwab-grade-II PCO in treating severe rigid kyphoscoliosis patients: comparative matched-group outcomes with minimum 2-year follow-up.

BACKGROUND CONTEXT: Standard partial facetectomies, (Smith-Petersen Osteotomy, (SPO), (Schwab-grade-I) and complete facet resection also known as Ponte osteotomy, (PO), (Schwab-grade-II) are narrowly akin and collectively appreciated as posterior column shortening osteotomies (PCOs). The former is considered a gentler osteotomy grade than the latter. The spine literature provides very little information on their comparison regarding perioperative complications and major curve correction rate outcomes. PURPOSE: To determine whether Schwab-grade-I PCO (SPO) and Schwab-grade-II PCO (PO) are comparably safe in the surgical management of severe rigid scoliosis or kyphoscoliosis patients. STUDY DESIGN/SETTING: Retrospective single-center comparative clinical study. PATIENT SAMPLE: A total of 38 patients with severe rigid scoliosis or kyphoscoliosis were propensity score matched in this study, (SPO-treated); n=21 (55.30%) and (PO-treated); n=17 (44.70%), who underwent primary spinal deformity corrective surgery, respectively. OUTCOME MEASURES: Outcomes included demographics, baseline pulmonary functional outcomes, perioperative complications incidence, hospital costs, Oswestry disability index (ODI), and the Scoliosis Research Society-22 (SRS-22) questionnaire scores. METHODS: Following approval by the Institutional Review Board (IRB) of Beijing Chaoyang Hospital-Affiliated Capital Medical University in Beijing, out of a total of 82 consecutive surgical patients with complete data demonstrating severe and/or rigid spinal deformity, a pool of 38 of the 82 (46.3%) propensity-matched adult (≥18 years) patients with severe rigid scoliosis or kyphoscoliosis defined with a preoperative major curve magnitude of ≥80° on anteroposterior plain radiographs, and flexibility of <25% on bending plain radiographs who underwent primary spinal deformity corrective surgery were retrospectively evaluated. The patients were dichotomized into two osteotomy groups: standard (partial) facetectomy (SPO-treated), n=21 with an average age of 24.67 years, (Schwab-grade-I PCO) and complete facet excision, (PO-treated), (ie, Schwab-grade-II PCO), n=17 with an average age of 23.12 years. The minimum follow-up period was 2 years. Primary outcomes included baseline demographics and clinical features. Secondary outcomes included perioperative [intraoperative, immediate, and 2-year postoperative] complication rates. Tertiary outcomes included perioperative ODI and SRS-22 scores. Statistical analyses were carried out by Student t-test and Pearson's Chi-square test (Fisher's Exact Test), through Python statistical software package. Statistical significance was set at (p<.05). RESULTS: Of the 38 matched severe rigid scoliosis or kyphoscoliosis patients, 55.30% (n=21) were SPO-treated and 44.70% (n=17) were PO-treated patients, respectively. The overall average age of patients was 23.97 years, with a female incidence of 76.32%. Major curve correction rates were 49.19% and 57.40% in SPO-treated and PO-treated patients, respectively, (p>.05). Immediately following surgery, comparable overall complication rates of 28.57% (n=6/21) versus 29.41% (n=5/17) were observed in the SPO-treated and PO-treated patients, respectively, (p=.726). We observed incidences of 9.52%, (n=2/21) versus 5.88%, (n=1/17) for surgical intensive care unit (SICU) admission, and incidences of 4.76%, (n=1/21) versus 5.88%, (n=1/17) for cardiopulmonary events in SPO-treated versus PO-treated patients following corrective surgery, respectively, (p>.05). The incidences of neurological deficits in the SPO-treated and PO-treated patients were respectively, 14.29%, (n=3/21) versus 17.65%, (n=3/17) immediately following surgery, (p>.05), and 0.00%, (n=0/21) in SPO-treated versus 14.28%, (n=3/21) in PO-treated patients at ≥2 years postoperative, (p<.05). Among the three patients that reported neurological deficits in the PO-treated group at ≥2 years postoperative, two patients had pre-existing baseline neurological deficits. The ODI score in the PO-treated group was significantly inferior at a minimum 2-year follow-up, (p<.05). CONCLUSIONS: In the current study, both SPO-treated and PO-treated patients demonstrated statistically comparable surgical complications immediately following corrective surgery. Severe rigid kyphoscoliosis patients with preexisting baseline neurological deficits were more inclined to sustain neurological morbidity following corrective surgery. PCO corrective techniques are warranted as safe options for treating patients with severe rigid spine deformity phenotypes.

Perioperative Low-Dose Ketamine for Postoperative Pain Management in Spine Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Objective: Although low-dose ketamine has been shown to be generally beneficial in terms of pain control in a variety of major surgery, there is no consensus regarding the effectiveness of supplemental ketamine analgesic use exclusively in spine surgery. The objective of this systematic review and meta-analysis of randomized controlled trials (RCTs) was to assess the efficacy and safety of perioperative low-dose ketamine for pain management and analgesic consumption in patients undergoing spine surgery. Methods: A comprehensive literature search was performed for relevant studies using PubMed, EMBASE, Web of Science, and Cochrane Library. Patients who received perioperative low-dose ketamine were compared to the control group in terms of postoperative pain intensity, opioid consumption, and adverse events. Patients were further categorized by ages and administration times for subgroup analysis. Results: A total of 30 RCTs comprising 1,865 patients undergoing elective spine surgery were included. Significantly lower pain intensity and less opioid consumption at 12 h, 24 h, and 48 h postoperatively and lower incidence of postoperative nausea and vomiting (PONV) were observed in the ketamine group (all P < 0.05). There was no significant difference of central nervous system (CNS) adverse events between groups. However, different efficacy of low-dose ketamine was detected when patients were categorized by ages and administration times. Conclusion: Perioperative low-dose ketamine demonstrated analgesic and morphine-sparing effect with no increased adverse events after spine surgery. However, this effect was not significant in pediatric patients. Only postoperative or intraoperative and postoperative administration could prolong the analgesic time up to 48 h postoperatively. Further studies should focus on the optimal protocol of ketamine administration and its effect on old age participants.