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Byline: L. Swadzba, B. Formanek, A. Maciejny The paper presents a review of heat-resistant coatings manufacture techniques for Ni-base superalloys. Modern techniques such as: Electron Beam Physical Vapor Deposition (EB-PVD), Low-Pressure Plasm Spray and modified (AltPt, Ale) aluminide coatings are described. Experimentally based results show the microstructure of Al-Cr and Al-Si coatings obtained by pack cementation technique. The coatings changes during their high-temperature service are utilized to determine the distribution of selected elements in coatings both before and after high temperature annealing. High hot-corrosion resistance of Si-modified aluminide coatings have been confirmed. Both microstructure and phase composition of the Al-Cr and Al-Si coatings depend on the chemical composition of the powder mixture applied in pack cementation technique. Chromium forms stable compounds with Al in the mixture while Si appears in the coating layers in a form of precipitation particles with elevated content of Mo, W, Ti and Cr. The Al-Si coatings show high hot corrosion resistance.

Byline: G. Dercz, K. Prusik, B. Formanek, L. Pajak The studied composite powder of high corrosion resistance was prepared using the Self-propagating High-temperature Synthesis (SHS) process. The as-prepared material was crushed and was subjected to a milling process by high-energy attritory mill for two and ten hours. The powder morphology was analysed through the Scanning Electron Microscopy (SEM) method. The structure investigations were performed using the SEM and XRD methods. The presence of Cr7C3, FeCr and FeO phases, besides the most desired FeAl(Cr), Cr3C2 and TiC ones, was noted. It was found that the FeAl(Cr) phase is of the ordered B2-type structure and the ordering degree diminishes with the increase of milling time. The crystallite size of this phase, both in the as-prepared state and after the milling process, is in the nanoscale. The crystallite size of the FeO phase diminishes to 75 nm in the sample ground for 10 h, whereas those of the other phases are above 100 nm for the as-prepared and ground samples.

Abstract: The process of obtaining cast aluminium composite of dispersive structure and hybrid reinforcement has been presented in the article. An Aluminium alloy (AlMg2) was modified with a powder mixture which, when in reaction with aluminium, reinforced the matrix with intermetallic phases and aluminium oxide. According to the technological conception, an assumption was made, that the cast composites would be produced in technological procedure shown in Fig. 1. The reinforcing phases were using Fe–Ti–Al powder mixtures with aluminium oxide formed in a self-propagating high-temperature synthesis (SHS). The structure and phase composition of the composite powder used for the matrix alloy modification are shown in Fig. 2. A composite alloy Al–FeAl–TiAl–Al2O3 was produced by casting method (gravity casting, mechanical mixing) after which its structure was determined. It was assumed that the final product of the applied production process will be an aluminium composite with hybrid reinforcement, consisting of Fe–Al and Ti–Al intermetallic phases and aluminium oxides. Optical microscopy, electron scanning microscopy and X-ray phase analysis were used to characterize the microstructure of the composites produced. Presence of aluminium, Al3Ti and Al13Fe4 phases and dispersed Al2O3 was confirmed in the composite by XRD method. The dispersion structure and phase composition of the composites are presented in Figs. 3–6. The composites formed in an in situ reaction constitute a newer generation of casts, in which dispersion reinforcement is obtained in the form of intermetallic and ceramic phases coherent with the matrix, very often below 1μm in size. The designed process allows for the structure modification of the applied casting aluminium alloys in different technological variants. [Copyright &y& Elsevier]

Abstract: The Ni(Cr)–TiC–Cr3C2–Cr7C3 composite powder was prepared by SHS (Self-propagating High-temperature Synthesis) process using elemental powders as starting materials. As-prepared powder was ground by an attritorial mill up to 10h. Micrographs and diffraction patterns were obtained using TEM. The X-ray diffraction data were analyzed by the Rietveld method and Toraya procedure. The Rietveld method was applied in the determination of phase abundance using Hill and Howard approach. The parameters of diffraction line profiles were analyzed by PRO-FIT Toraya procedure. The crystallite sizes and lattice distortions were analyzed using Williamson–Hall method. It was stated that the crystallite size of Ni(Cr) phase diminishes to nanoscale after 5h milling whereas the crystallite size of the other phases is still above 100nm for applied milling time. [Copyright &y& Elsevier]

Abstract: The NiAl–TiC–Al2O3 composite powder was prepared by self-propagating high-temperature synthesis (SHS) process using elemental powders as starting materials. As-prepared powder was ground by a high-energy attritorial mill for up to 40h. The X-ray diffraction methods were used for the structure analysis of the as-prepared and ground samples. The Rietveld method was applied for the verification of the qualitative and quantitative phase composition of the studied material. The parameters of diffraction line profiles were determined by PRO-FIT Toraya procedure. The crystallite sizes and lattice distortions were analyzed by Williamson–Hall method. It was found that during high-energy milling a significant decrease of crystallite size is observed only for NiAl phase. The crystallite size of this phase diminishes to 17nm when the milling time rises to 40h. [Copyright &y& Elsevier]

Study Design: A retrospective database study., Objectives: The purpose of the current study was to investigate the impact of hyperlipidemia (HLD) on the incidence of perioperative complications associated with posterior cervical spine fusion (PCF)., Background: HLD is a very common disease that leads to atherosclerosis. Therefore, it can cause fatal diseases as well as lifestyle-related diseases. The possible impact of HLD on outcomes after PCF has not yet been investigated., Methods: Patients with cervical degeneration underwent initial PCF from 2010 through the third quarter of 2020 using the MSpine subset of the PearlDiver Patient Record Database. The incidence of perioperative complications was queried using relevant ICD-9, 10, and CPT codes. χ 2 analysis was performed in age-, sex-, and Charlson Comorbidity Index (CCI)-matched populations to compare between non-HLD and HLD patients in each single-level and multilevel PCF., Results: Through propensity score matching, 1600 patients each in the HLD and non-HLD groups were analyzed in the single-level PCF, 6855 patients were analyzed in the multilevel PCF were analyzed. The comorbidity of HLD significantly decreased the incidence of respiratory failure in single-level PCF (OR=0.58, P <0.01). In the multilevel PCF, the presence of HLD increased the incidence of cervicalgia (OR=1.26, P =0.030). On the contrary, the incident of spinal cord injury (OR=0.72, P <0.01), dysphagia (OR=0.81, P =0.023), respiratory failure (OR=0.85, P =0.030), pneumonia (OR=0.70, P =0.045), neurological bladder (OR=0.84, P =0.041), and urinary tract infection (OR=0.85, P =0.021) in the HLD group were significantly lower than those in non-HLD group., Conclusions: In the current study, the presence of HLD significantly increased the incidence of postoperative cervicalgia in multilevel PCF. On the other hand, the incidence of some complications was significantly decreased with HLD. Further studies are needed taking into account other factors such as the treatment of HLD, its efficacy, and intraoperative events., Level of Evidence: Level III., Competing Interests: Disclosures outside of submitted work: J.C.W.- royalties: SeaSpine, Depuy, Zimmer; consulting - Precision OS (no money paid); expert testimony; AO Foundation Board (honorarium), National Spine Health Foundation (volunteer); stocks/personal investment: PearlDiver, Bone Biologics, Surgitech; Fellowship Funding (paid to institution): AO Foundation. Z.B. – Grants/ Research support: AO Spine (co-PI on a AOSpine Knowledge Forum grant, Paid directly to institution/employer); Nexus Spine (Paid directly to institution/employer), Medical Metrics (Paid directly to institution/employer); MiMedx (past, Paid directly to institution/employer), SBIR NIH (past, Paid directly to institution/employer); Medical Metrics (past, Paid directly to institution/employer); Next Science (past, Paid directly to institution/employer); Consultancy: Next Science (paid directly to institution/employer); NIH (advisor consultant); Scientific Advisory Board: Medtronic, Medical Metrics; Trips/Travel: AO Spine (Travel Expense Reimbursement, travel reimbursements for AO Spine Knowledge forum meetings and congresses), NASS (Travel Expense Reimbursement); Board of Directors: LSRS (Nonfinancial, Co-chair of Program Committee); Committees: AO Spine Knowledge Forum Degenerative (Steering Committee Member); North American Spine Society: Research Project Management Committee (Vice chair), Section on Biologics & Basic Research (Co-chair), The Spine Journal Peer Reviewers (Committee member). Patents (issued): Biomarkers for painful intervertebral discs and methods of use thereof, the remaining authors declare no conflict of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Study Design: Retrospective cohort study., Objective: To analyze the effect of hyperlipidemia (HLD) on postoperative complications in patients who underwent anterior cervical discectomy and fusion (ACDF)., Summary of Background Data: ACDF represents the standard procedure performed for focal anterior nerve root or spinal cord compression with low complication rates. HLD is well known as a risk factor for major complications after vascular and transplant surgery, and orthopedic surgery. To date, there have been no studies on HLD as a risk factor for cervical spine surgery., Patients and Methods: Patients who underwent ACDF from 2010 through quarter 3 of 2020 were enrolled using the MSpine subset of the PearlDiver Patient Record Database. The patients were divided into single-level ACDF and multilevel ACDF groups. In addition, each group was divided into subgroups according to the presence or absence of HLD. The incidence of surgical and medical complications was queried using relevant International Classification of Disease and Current Procedural Terminology codes. Charlson Comorbidity Index was used as a broad measure of comorbidity. χ 2 analysis, with populations matched for age, sex, and Charlson Comorbidity Index, was performed., Results: A total of 24,936 patients who underwent single-level ACDF and 26,921 patients who underwent multilevel ACDF were included. In the multilevel ACDF group, wound complications were significantly higher in the patients with HLD. Among medical complications, myocardial infarction, renal failure, and urinary tract infection/urinary incontinence were significantly higher in the patients with HLD in both groups. Revision surgery and readmission were significantly higher in the patients with HLD who underwent multilevel ACDF., Conclusions: In patients who underwent ACDF, several surgical and medical complications were found to be higher in patients with HLD than in patients without HLD. Preoperative serum lipid concentration levels and management of HLD should be considered during preoperative planning to prevent postoperative complications in patients undergoing ACDF., Competing Interests: Z.B.–Grants/Research support: AO Spine (co-PI on a AO Spine Knowledge Forum grant, Paid directly to institution/employer); Nexus Spine (Paid directly to institution/employer), Medical Metrics (Paid directly to institution/employer); MiMedx (past, Paid directly to institution/employer), SBIR NIH (past, Paid directly to institution/employer); Medical Metrics (past, Paid directly to institution/employer); Next Science (past, Paid directly to institution/employer); Consultancy: Next Science (paid directly to institution/employer); NIH (advisor consultant); Scientific Advisory Board: Medtronic, Medical Metrics; Trips/Travel: AO Spine (Travel Expense Reimbursement, travel reimbursements for AO Spine Knowledge forum meetings and congresses), NASS (Travel Expense Reimbursement); Board of Directors: LSRS (Nonfinancial, Co-chair of Program Committee); Committees: AO Spine Knowledge Forum Degenerative (Steering Committee Member); North American Spine Society: Research Project Management Committee (Vice chair), Section on Biologics & Basic Research (Co-chair), The Spine Journal Peer Reviewers (Committee member). Patents (issued): Biomarkers for painful intervertebral discs and methods of use thereof. J.C.W.-royalties: SeaSpine, Depuy, Zimmer; consulting - Precision OS (no money paid); expert testimony; AO Foundation Board (honorarium), National Spine Health Foundation (volunteer); stocks/personal investment: PearlDiver, Bone Biologics, Surgitech; Fellowship Funding (paid to institution): AO Foundation. The remaining authors declare no conflict of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Distal radius fractures (DRFs) are one of the most common types of wrist fracture and can be subdivided into intra- and extra-articular fractures. Compared with extra-articular DRFs which spare the joint surface, intra-articular DRFs extend to the articular surface and can be more difficult to treat. Identification of articular involvement can provide valuable information about the characteristics of fracture patterns. In this study, a two-stage ensemble deep learning framework was proposed to differentiate intra- and extra-articular DRFs automatically on posteroanterior (PA) view wrist X-rays. The framework firstly detects the distal radius region of interest (ROI) using an ensemble model of YOLOv5 networks, which imitates the clinicians' search pattern of zooming in on relevant regions to assess abnormalities. Secondly, an ensemble model of EfficientNet-B3 networks classifies the fractures in the detected ROIs into intra- and extra-articular. The framework achieved an area under the receiver operating characteristic curve of 0.82, an accuracy of 0.81, a true positive rate of 0.83 and a false positive rate of 0.27 (specificity of 0.73) for differentiating intra- from extra-articular DRFs. This study has demonstrated the potential in automatic DRF characterization using deep learning on clinically acquired wrist radiographs and can serve as a baseline for further research in incorporating multi-view information for fracture classification., (© 2023. Crown.)

Study Design: Retrospective comparative study., Objectives: To compare the perioperative complications of propensity score-matched cohorts of patients with degenerative cervical myelopathy (DCM), who were treated with anterior cervical discectomy and fusion (ACDF), posterior laminectomy with fusion, or laminoplasty., Methods: The Humana PearlDiver Patient Record Database was queried using the International Classification of Diseases (ICD-9 and ICD-10) and the Current Procedural Terminology (CPT) codes. Propensity score-matched analysis was done using multiple Chi-squared tests with Bonferroni correction of the significance level., Results: Cohorts of 11,790 patients who had ACDF, 2,257 patients who had posterior laminectomy with fusion, and 477 patients who had laminoplasty, were identified. After propensity score matching, all the 3 groups included 464 patients. The incidence of dysphagia increased significantly following ACDF compared to laminoplasty, P < 0.001, and in laminectomy with fusion compared to laminoplasty, P < 0.001. The incidence of new-onset cervicalgia was higher in ACDF compared to laminoplasty, P = 0.005, and in laminectomy with fusion compared to laminoplasty, P = 0.004. The incidence of limb paralysis increased significantly in laminectomy with fusion compared to ACDF, P = 0.002. The revision rate at 1 year increased significantly in laminectomy with fusion compared to laminoplasty, P < 0.001, and in ACDF compared to laminoplasty, P < 0.001., Conclusions: The incidence of dysphagia following laminectomy with fusion was not different compared to ACDF. Postoperative new-onset cervicalgia and revisions were least common in laminoplasty. The highest rate of postoperative limb paralysis was noticed in laminectomy with fusion.

Study Design: Retrospective cross-sectional study., Objectives: To determine if pre-operative albumin and CRP can predict post-operative infections after lumbar surgery., Methods: Patients who underwent an anterior lumbar interbody fusion (ALIF), posterior lumbar interbody fusion (PLIF), or lumbar discectomy were identified using a patient record database (PearlDiver) and were included in this retrospective study. Patients were stratified by Charlson Comorbidity Index (CCI) scores and pre-operative albumin and CRP status. Post-operative complications included deep infections and urinary tract infections within 3 months of the surgery and revisions within 1 year of the surgery., Results: 74,280 patients were included in this study. 21,903 had pre-operative albumin or CRP lab values. 7,191 (33%), 12,183 (56%), and 2,529 (12%) patients underwent an ALIF, PLIF, and a lumbar discectomy, respectively. 16,191 did not have any complication (74%). The most common complication was UTI (16%). Among all patients, hypoalbuminemia was a significant risk factor for deep infection and UTI after ALIF, deep infection, UTI, and surgical revision after PLIF, and deep infection after lumbar discectomy. Elevated CRP was a significant risk factor for deep infection after ALIF, UTI after PLIF, and deep infection after lumbar discectomy in patients with a CCI ≤ 3., Conclusions: Pre-operative hypoalbuminemia and elevated CRP were significant risk factors for deep infection, UTI, and/or revision, after ALIF, PLIT, and/or lumbar discectomy. Future studies with a larger population of patients with low albumin and high CRP values are needed to further elaborate on the current findings.

Purpose: To describe the incidence of complications associated with cervical spine surgery and post-operative physical therapy (PT), and to identify if the timing of initiation of post-operative PT impacts the incidence rates., Methods: MOrtho PearlDiver database was queried using billing codes to identify patients who had undergone Anterior Cervical Discectomy and Fusion (ACDF), Posterior Cervical Fusion (PCF), or Cervical Foraminotomy and post-operative PT from 2010-2019. For each surgical procedure, patients were divided into three 12-week increments for post-operative PT (starting at post-operative weeks 2, 8, 12) and then matched based upon age, gender, and Charlson Comorbidity Index score. Each group was queried to determine complication rates and chi-square analysis with adjusted odds ratios, 95% confidence intervals, and p-values were used., Results: Following matching, 3,609 patients who underwent cervical spine surgery at one or more levels and had post-operative PT (ACDF:1784, PCF:1593, and cervical foraminotomy:232). The most frequent complications were new onset cervicalgia (2-14 weeks, 8-20 weeks, 12-24 weeks): ACDF (15.0%, 14.0%, 13.0%), PCF (18.8%, 18.0%, 19.9%), cervical foraminotomy (16.8%, 16.4%, 19.4%); revision: ADCF (7.9%, 8.2%, 7.4%), PCF (9.3%, 10.6%, 10.2%), cervical foraminotomy (11.6%, 10.8% and 13.4%); wound infection: ACDF (3.3%, 3.4%, 3.1%), PCF (8.3%, 8.0%,7.7%), cervical foraminotomy (5.2%, 6.5%, < 4.7%). None of the comparisons were statistically significant., Conclusion: The most common post-operative complications included new onset cervicalgia, revision and wound infection. Complications rates were not impacted by the timing of initiation of PT whether at 2, 8, or 12 weeks post-operatively., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Failed back surgery syndrome (FBSS) is a significant cause of lumbar disability and is associated with severe patient morbidity. As the etiology of FBSS is not completely elucidated, the risk factors and evaluation of patients with FBSS remains challenging. Our analysis of a wide variety of operation types, clinical setting, and their correlation to FBSS seeks to allow fellow clinicians to be aware of the potential risk factors that leads to this devastating diagnosis., Methods: Data were obtained for patients undergoing anterior lumbar fusion, posterior lumbar fusion, or decompression procedures from January 2010 to December 2017 from the Mariner insurance database. Rates of FBSS at six- and twelve-months post-surgery were determined for patients undergoing single/multilevel procedures according to place of service, and approach/procedure type., Results: From 2010 to 2017, 102,047 patients underwent lumbar fusion or decompression surgery (54% decompression procedures, 36% posterior fusions, and 8.9% anterior fusions).5.4% of patients were diagnosed with FBSS within six months of the index procedure, and 8.4% were diagnosed with FBSS within twelve months. FBSS was higher in the inpatient (6.0%) vs. outpatient (4.3%) cohort. Among the surgical techniques, multi-level procedures had significantly higher rates of FBSS than single-level procedures, the highest being 10% in multi-level inpatient decompression procedures (p < 0.05)., Conclusion: The highest rates of FBSS occurred in in the elderly (age group 70-74), for those patients whose index procedure was received in an inpatient setting, as well as for those receiving a multi-level surgery., (Copyright © 2022 Elsevier Ltd. All rights reserved.)