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This Technical Note describes a surgical approach that combines circumferential fiber augmentation with transtibial pullout repair for the treatment of medial meniscal posterior root tears. To address the challenge of meniscal extrusion and subsequent joint space narrowing that predisposes to osteoarthritis, this technique uses an artificial ligament to add circumferential collagen fiber reinforcement to improve meniscal extrusion. This integrated approach is designed to address the limitations of conventional tibial pullout repairs by potentially providing better results in preventing meniscal extrusion. Despite the promising benefits, the complexity of this combined technique may present a learning curve for surgeons and require specialized training. This technique represents a significant advancement in the surgical treatment of medial meniscal posterior root tears and offers a promising solution to reduce the risk of osteoarthritis progression in affected patients.

Abstract This paper presents a novel computational design and fabrication method for fabric-based soft pneumatic actuators (FSPAs) that use Turing patterns, inspired by Alan Turing’s morphogenesis theory. These inflatable structures can adapt their shapes with simple pressure changes and are applicable in areas like soft robotics, airbags, and temporary shelters. Traditionally, the design of such structures relies on isotropic materials and the designer’s expertise, often requiring a trial-and-error approach. The present study introduces a method to automate this process using advanced numerical optimization to design and manufacture fabric-based inflatable structures with programmable shape-morphing capabilities. Initially, an optimized distribution of the material orientation field on the surface membrane is achieved through gradient-based orientation optimization. This involves a comprehensive physical deployment simulation using the nonlinear shell finite element method, which is integrated into the inner loop of the optimization algorithm. This continuous adjustment of material orientations enhances the design objectives. These material orientation fields are transformed into discretized texture patterns that replicate the same anisotropic deformations. Anisotropic reaction-diffusion equations, using diffusion coefficients determined by local orientations from the optimization step, are then utilized to create space-filling Turing pattern textures. Furthermore, the fabrication methods of these optimized Turing pattern textures are explored using fabrics through heat bonding and embroidery. The performance of the fabricated FSPAs is evaluated through three different deformation shapes: C-shaped bending, S-shaped bending, and twisting.

Abstract Metabolic dysfunction-associated steatohepatitis (MASH), previously called non-alcoholic steatohepatitis (NASH), is a growing concern worldwide, with liver fibrosis being a critical determinant of its prognosis. Monocyte-derived macrophages have been implicated in MASH-associated liver fibrosis, yet their precise roles and the underlying differentiation mechanisms remain elusive. In this study, we unveil a key orchestrator of this process: long chain saturated fatty acid-Egr2 pathway. Our findings identify the transcription factor Egr2 as the driving force behind monocyte differentiation into hepatic lipid-associated macrophages (hLAMs) within MASH liver. Notably, Egr2-deficiency reroutes monocyte differentiation towards a macrophage subset resembling resident Kupffer cells, hampering hLAM formation. This shift has a profound impact, suppressing the transition from benign steatosis to liver fibrosis, demonstrating the critical pro-fibrotic role played by hLAMs in MASH pathogenesis. Long-chain saturated fatty acids that accumulate in MASH liver emerge as potent inducers of Egr2 expression in macrophages, a process counteracted by unsaturated fatty acids. Furthermore, oral oleic acid administration effectively reduces hLAMs in MASH mice. In conclusion, our work not only elucidates the intricate interplay between saturated fatty acids, Egr2, and monocyte-derived macrophages but also highlights the therapeutic promise of targeting the saturated fatty acid-Egr2 axis in monocytes for MASH management.

Abstract Accumulating evidence suggests that endothelial cells can be useful therapeutic targets. One of the potential targets is an endothelial cell-specific protein, Roundabout4 (ROBO4). ROBO4 has been shown to ameliorate multiple diseases in mice, including infectious diseases and sepsis. However, its mechanisms are not fully understood. In this study, using RNA-seq analysis, we found that ROBO4 downregulates prostaglandin-endoperoxide synthase 2 (PTGS2), which encodes cyclooxygenase-2. Mechanistic analysis reveals that ROBO4 interacts with IQ motif-containing GTPase-activating protein 1 (IQGAP1) and TNF receptor-associated factor 7 (TRAF7), a ubiquitin E3 ligase. In this complex, ROBO4 enhances IQGAP1 ubiquitination through TRAF7, inhibits prolonged RAC1 activation, and decreases PTGS2 expression in inflammatory endothelial cells. In addition, Robo4-deficiency in mice exacerbates PTGS2-associated inflammatory diseases, including arthritis, edema, and pain. Thus, we reveal the molecular mechanism by which ROBO4 suppresses the inflammatory response and vascular hyperpermeability, highlighting its potential as a promising therapeutic target for inflammatory diseases.

Objective: Postoperative lymphopenia is reported as an excellent indicator to predict surgical-site infection (SSI) after spine surgery. However, there is still controversy concerning which serological markers can predict spinal SSI. This study aims to evaluate excellent and early indicators for detecting SSI, focusing on spine instrumented surgery. Materials and Methods: This study included 268 patients who underwent spinal instrumented surgery from January 2022 to December 2023 (159 female and 109 male, average 62.9 years). The SSI group included 20 patients, and the non-SSI group comprised 248 patients. Surgical time, intraoperative blood loss, and glycemic levels were measured in both groups. The complete blood cell counts, differential counts, albumin, and C-reactive protein (CRP) levels were measured pre-surgery and postoperative on Days 1, 3, and 7. In comparing the groups, the Mann–Whitney U test analysis was used for continuous variables, while the chi-squared test and Fisher’s exact test were used for dichotomous variables. Results: The incidence of SSI after spinal instrumentation was 7.46% and was relatively higher in scoliosis surgery. The SSI group had significantly longer surgical times (248 min vs. 180 min, p = 0.0004) and a higher intraoperative blood loss (772 mL vs. 372 mL, p < 0.0001) than the non-SSI group. In the SSI group, the Day 3 (10.5 ± 6.2% vs. 13.8 ± 6.0%, p = 0.012) and Day 7 (14.4 ± 4.8% vs. 18.8 ± 7.1%, p = 0.012) lymphocyte ratios were lower than the non-SSI group. Albumin levels on Day 1 in the SSI group were lower than in the non-SSI group (2.94 ± 0.30 mg/dL vs. 3.09 ± 0.38 mg/dL, p = 0.045). There is no difference in CRP and lymphocyte count between the two groups. Conclusions: SSI patients had lower lymphocyte percentages than non-SSI patients, which was a risk factor for SSI, with constant high inflammation. The Day 3 lymphocyte percentage may predict SSI after spinal instrumented surgery.

The 9th International Tribology Conference, Fukuoka 2023 was held on 25–30 September 2023 at Fukuoka International Congress Center in Fukuoka City, Japan. The number of participants was 975 from 30 countries and regions, and the number of papers presented was 676. We thank all the people who joined and contributed to ITC. Papers submitted to this special issue went through peer-review process. Twenty papers were already published in Part 1, and 19 papers were accepted for publication in this Part 2. On behalf of the Organizing Committee, we would like to thank all the authors for their contributions, and also thank the editors, reviewers and the editorial office of Tribology Online for their efforts. Taking this opportunity, we would like to include in the next page the manuscript of the congratulatory speech delivered by Professor Masato Tanaka in Banquet on Thursday, 28 September, 2023

Generalized arterial calcification of infancy (GACI) is a rare disease characterized by arterial calcification. GACI is caused by a mutation in the ENPP1 or ABCC6 genes. GACI causes severe hypertension and heart failure, and approximately 50% of patients die within the first 6 months. In particular, preterm infants with GACI often die due to immature cardiac function. Bisphosphonates are effective in treating GACI; however, no standardized treatment regimen is available. We experienced a case of a preterm infant with GACI born at 30 weeks gestation. Ultrasonography showed high-intensity lesions in the arteries, and computed tomography revealed calcification of the arteries throughout the body, leading to the diagnosis of GACI. We administered intravenous pamidronate, and her cardiac contraction improved. The initial scheduled interval between drug administrations was 2 months. However, the cardiac contraction worsened 1 month after the pamidronate administration. Therefore, we decreased the dosing interval and administered a second course of pamidronate, which improved her cardiac function. We then switched to oral etidronate. To improve the morbidity and mortality rates of preterm infants with GACI, it is important to obtain an early diagnosis of GACI by investigating high-intensity lesions in the arteries and performing early administration of an appropriate type of bisphosphonate.

Abstract Shape-morphing structures that can reconfigure their shape to adapt to diverse tasks are highly desirable for intelligent machines in many interdisciplinary fields. Shape memory polymers are one of the most widely used stimuli-responsive materials, especially in 3D/4D printing, for fabricating shape-morphing systems. They typically go through a hot-programming step to obtain the shape-morphing capability, which possesses limited freedom of reconfigurability. Cold-programming, which directly deforms the structure into a temporary shape without increasing the temperature, is simple and more versatile but has stringent requirements on material properties. Here, we introduce grayscale digital light processing (g-DLP) based 3D printing as a simple and effective platform for fabricating shape-morphing structures with cold-programming capabilities. With the multimaterial-like printing capability of g-DLP, we develop heterogeneous hinge modules that can be cold-programmed by simply stretching at room temperature. Different configurations can be encoded during 3D printing with the variable distribution and direction of the modular-designed hinges. The hinge module allows controllable independent morphing enabled by cold programming. By leveraging the multimaterial-like printing capability, multi-shape morphing structures are presented. The g-DLP printing with cold-programming morphing strategy demonstrates enormous potential in the design and fabrication of shape-morphing structures.

Abstract We present a construction method for reduced-order models (ROMs) to explore alternatives to numerical simulations. The proposed method can efficiently construct ROMs for non-linear problems with contact and impact behaviors by using tensor decomposition for factorizing multidimensional data and Akima-spline interpolation without tuning any parameters. First, we construct learning tensor data of nodal displacements or accelerations using finite element analysis with some representative parameter sets. Second, the data are decomposed into a set of mode matrices and one small core tensor using Tucker decomposition. Third, Akima-spline interpolation is applied to the mode matrices to predict values within the data range. Finally, the time history responses with new parameter sets are generated by multiplying the expanded mode matrices and small core tensor. The performance of the proposed method is studied by constructing ROMs for airbag impact simulations based on limited learning data. The proposed ROMs can accurately predict airbag deployment behavior even for new parameter sets using the Akima-spline interpolation scheme. Furthermore, an extremely high data compression ratio (more than 1000) and efficient predictions of the response surfaces and Pareto frontier (2000 times faster than that of full finite element analyses using all parameter sets) can be realized.

Despite recent progress in additive manufacturing of organic materials, multimaterial additive manufacturing remains challenging. Here, the authors design a resin design that can be used for singlevat single-cure grayscale digital light processing 3D printing where light intensity can locally control the conversion of monomers to form from a highly stretchable soft organogel to a stiff thermoset within in a single layer of printing

Study Design This is a virtual three-dimensional (3D) imaging study examining computed tomography (CT) data to investigate instrumentation placement. Purpose In this study, we aim to clarify the ideal entry point and trajectory of the sacral alar iliac (SAI) screw in relationship to the dorsal foramen at S1 and the respective nerve root. Overview of Literature To the best of our knowledge, there is yet no detailed 3D imaging study on the ideal entry point of the SAI screw. Despite the evidence suggesting that the dorsal foramen at S1 is a landmark on the sacrum, the S1 nerve root disruption is a general concern during the insertion of SAI screws. No other study has been published examining the nerve root location at the S1and SAI screw insertions. Methods Preoperative CT data from 26 patients pertaining to adult spinal deformities were investigated in this study. We applied a 3D image processing method for a detailed investigation. Virtual cylinders were used to mimic SAI screws. These were placed to penetrate the sacral iliac joint without violating the other cortex. We then assessed the trajectory of the longest SAI screw and the ideal entry point of SAI using a color mapping method on the surface of the sacrum. We measured the location of the nerve root at S1 in relation to the foramen at S1 and the sacral surface. Results As per the results of our color mapping, it was determined that areas that received high scores are located medially and caudally to the dorsal foramen of S1. The mean angle between a horizontal line and a line connecting the medial edge of the foramen and nerve root at S1 was 93.5°. The mean distances from the dorsal medial edge of the foramen and sacral surface to S1 nerve root were 21.8 mm and 13.9 mm, respectively. Conclusions The ideal entry point of the SAI screw is located medially and caudally to the S1 dorsal foramen based on 3D digital mapping. It is also shown that this entry point spares the S1 nerve root from possible iatrogenic injuries.

Objectives and Background: To present a novel technique of treatment for a patient with basilar invagination. Basilar invagination (BI) is a congenital condition that can compress the cervicomedullary junction, leading to neurological deficits. Severe cases require surgical intervention, but there is debate over the choice of approach. The anterior approach allows direct decompression but carries high complication rates, while the posterior approach provides indirect decompression and offers good stability with fewer complications. Materials and Methods: A 15-year-old boy with severe myelopathy presented to our hospital with neck pain, bilateral upper limb muscle weakness, and hand numbness persisting for 4 years. Additionally, he experienced increased numbness and gait disturbance three months before his visit. On examination, he exhibited hyperreflexia in both upper and lower limbs, muscle weakness in the bilateral upper limbs (MMT 4), bilateral hypoesthesia below the elbow and in both legs, mild urinary and bowel incontinence, and a spastic gait. Radiographs revealed severe basilar invagination (BI). Preoperative images showed severe BI and that the spinal cord was severely compressed with odontoid process. Results: The patient underwent posterior surgery with the C-arm free technique. All screws including occipital screws were inserted into the adequate position under navigation guidance. Reduction was achieved with skull rotation and distraction. A follow-up at one year showed the following results: Manual muscle testing results and sensory function tests showed almost full recovery, with bilateral arm recovery (MMT 5) and smooth walking. The cervical Japanese Orthopedic Association score of the patient improved from 9/17 to 16/17. Postoperative images showed excellent spinal cord decompression, and no major or severe complications had occurred. Conclusions: Basilar invagination alongside Klippel–Feil syndrome represents a relatively uncommon condition. Utilizing a posterior approach for treating reducible BI with a C-arm-free technique proved to be a safe method in addressing severe myelopathy. This novel navigation technique yields excellent outcomes for patients with BI.

Objectives: To investigate the outcomes of early balloon kyphoplasty (BKP) intervention compared with late intervention for osteoporotic vertebral fracture (OVF). Background: Osteoporotic vertebral fracture can lead to kyphotic deformity, severe back pain, depression, and disturbances in activities of daily living (ADL). Balloon kyphoplasty has been widely utilized to treat symptomatic OVFs and has proven to be a very effective surgical option for this condition. Furthermore, BKP is relatively a safe and effective method due to its reduced acrylic cement leakage and greater kyphosis correction. Materials and Methods: A retrospective cohort study was conducted at our hospital for patients who underwent BKP for osteoporotic vertebral fractures in the time frame between January 2020 and December 2022. Ninety-nine patients were included in this study, and they were classified into two groups: in total, 36 patients underwent early BKP intervention (EI) at Results: Adjacent segmental fractures were more frequently observed in the LI group compared to the EI group (33.3% vs. 13.9%, p = 0.034). There was a significant improvement in postoperative vertebral angles in both groups (p = 0.036). The cement volume injected was 7.42 mL in the EI, compared with 6.3 mL in the LI (p = 0.007). The mean surgery time was shorter in the EI, at 30.2 min, compared with 37.1 min for the LI, presenting a significant difference (p = 0.0004). There was no statistical difference in the pain visual analog scale (VAS) between the two groups (p = 0.711), and there was no statistical difference in cement leakage (p = 0.192). Conclusions/Level of Evidence: Early BKP for OVF treatment may achieve better outcomes and fewer adjacent segmental fractures than delayed intervention.

Introduction: S2 alar-iliac screw (S2AIS) insertion for lumbosacral fixation is becoming a common procedure for deformity surgeries. However, studies that have reported the anatomy and morphometric features of the pelvis for S2AIS insertion in the Japanese samples are scarce. This study aimed to elucidate the morphometric features of the pelvis regarding S2AIS insertion in the Japanese samples. Methods: We used 60 computed tomography scans of the pelvis (30 men and 30 women). The entry point for the S2AIS was determined as 1-mm lateral and 1-mm distal to the S1 dorsal sacral foramen. We resliced the plane in which the pelvis was sectioned obliquely from this entry point to the anterior inferior iliac spine in the sagittal plane. We bilaterally placed the shortest and longest virtual S2AISs in this plane using a 4-mm margin. We analyzed the length, angle, and safety of the determined trajectory and compared these measurements according to sex and age. Results: The median longest and shortest screw lengths were 108.1 and 103.3 mm, respectively. The median longest and shortest distances from the entry point to the sacroiliac joint were 31.2 and 28.2 mm, respectively. The median smallest and largest lateral angulations were 40.7° and 47.3°, respectively. The median angle range was 4.2°. The median caudal angulation was −2.8°. The median shortest and longest distances from the S2AISs to the acetabular roof were 23.5 and 27.4 mm, respectively. The median distance from the S2AISs to the sciatic notch was 23.1 mm. Assuming the insertion of screw with a diameter of 8 mm, S2AIS insertion was difficult in 32 of 120 (27%) screws because the dorsal cortex of the sacrum was damaged. Conclusions: Screw length and lateral angulation were similar to those in previous studies. Insertion difficulty occurred in 27% of screws.

Although mRNA coronavirus disease 2019 (COVID-19) vaccines have been reported for high effectiveness against symptoms, it remains unclear whether post-vaccination infections are less symptomatic than infections in vaccine-naive individuals. We included patients with COVID-19 diagnosed by polymerase chain reaction tests during Japan’s alpha and delta variant epidemics. COVID-19 symptoms at approximately 4 weeks were compared based on COVID-19 vaccination status. In total, 398 cases (372 symptomatic and 26 asymptomatic; 286 unvaccinated, 66 vaccinated with one dose, and 46 with two doses) were analyzed. The most common symptoms were fever (78.4%), fatigue (78.4%), cough (74.4%), loss of taste or smell (62.8%), and headache (59.8%). Post-vaccination infections were significantly less likely to be symptomatic. Possible confounder-adjusted odds ratios of two vaccine doses against fatigue, dry eyes and mouth, insomnia, fever, shortness of breath, unusual muscle pains, and loss of taste or smell were 0.18 (95% confidence interval [CI]: 0.09–0.38), 0.22 (95% CI: 0.08–0.59), 0.33 (95% CI: 0.14–0.80), 0.31 (95% CI: 0.15–0.63), 0.36 (95% CI: 0.16–0.76), 0.40 (95% CI: 0.19–0.82), and 0.44 (95% CI: 0.22–0.87), respectively. Post-vaccination infections after two mRNA COVID-19 vaccine doses show milder and fewer symptoms than infections in unvaccinated patients, highlighting the effectiveness of vaccination.

Background and Objectives: The implementation of intraoperative imaging in the procedures performed under the guidance of the same finds its history dating back to the early 1990s. This practice was abandoned due to many deficits and practicality. Later, fluoroscopy-dependent techniques were developed and have been used even in the present time, albeit with several disadvantages. With the recent advancement of several complex surgical techniques, which demand higher accuracy and are in conjunction with the existence of radiation exposure hazard, C-arm-free techniques were introduced. In this review study, we aim to demonstrate the various types of these techniques performed in our hospital. Materials and Methods: We have retrospectively analyzed and collected imaging data of C-arm-free, minimally invasive techniques performed in our hospital. The basic steps of the procedures are described, following with a discussion, along with the literature of findings, enlisting the merits and demerits. Results: MIS techniques of the thoracolumbar and lumbar spine that do not require the use of the C-arm can offer excellent results with high precision. However, several disadvantages may prevail in certain circumstances such as the navigation accuracy problem where in the possibility of perioperative complications comes a high morbidity rate. Conclusions: The accustomedness of performing these techniques requires a steep learning curve. The increase in accuracy and the decrease in radiation exposure in complex spinal surgery can overcome the burden hazards and can prove to be cost-effective.

Background and Objectives: To present a new spinal shortening technique for tethered cord syndrome. Tethered cord syndrome (TCS) is a debilitating condition leading to progressive neurological decline. Surgical detethering for TCS is the gold standard of treatment. However, symptomatic retethering of TCS has been reported in 5%–50% of patients after initial release. To solve this problem, posterior spinal shortening osteotomy has been reported. This technique has risks of massive blood loss and neurological deterioration. The authors hereby report a new safe spinal shortening technique for tethered cord syndrome. Materials and Methods: A 31-year-old man with gait disturbance was referred to our hospital. After the delivery of treatment, he underwent surgical untethering of the spinal cord in another hospital. He had hyperreflexia of the Achilles tendon reflex and bilateral muscle weakness of the legs (MMT 3-4). He also had urinary and bowel incontinence, and total sensory loss below L5. An anteroposterior lumbar radiogram indicated partial laminectomy of L3 and L4. Lumbar MRI showed retethering of spinal cord. Results: The patient underwent a new spinal shortening technique for tethered cord syndrome under the guidance of O-arm navigation. First, from the anterior approach, disectomy from T12 to L3 was performed. Second, from the posterior approach, Ponte osteotomy was performed from T12 to L3, shortening the spinal column by 15 mm. The patient was successfully treated surgically. Postoperative lumbar MRI showed that the tension of the spinal cord was released. Manual muscle testing results and the sensory function of the left leg had recovered almost fully upon final follow-up at one year. Conclusions: A retethered spinal cord after initial untethering is difficult to treat. This new spinal shortening technique can represent another good option to release the tension of the spinal cord.

Abstract Background Symptomatic pseudarthrosis and cage migration/protrusion are difficult complications of transforaminal or posterior lumbar interbody fusion (TLIF/PLIF). If the patient experiences severe radicular symptoms due to cage protrusion, removal of the migrated cage is necessary. However, this procedure is sometimes very challenging because epidural adhesions and fibrous union can be present between the cage and vertebrae. We describe a novel classification and technique utilizing a navigated osteotome and the oblique lumbar interbody fusion at L5/S1 (OLIF51) technique to address this problem. Methods This retrospective study investigated consecutive patients with degenerative lumbar diseases who underwent TLIF/PLIF. Symptomatic cage migration was evaluated by direct examination, radiography, and/or computed tomography (CT) at 1, 3, 6, 12, and 24 months of follow-up. Cage migration/protrusion was defined as symptomatic cage protrusion > 5 mm from the posterior border of the over and underlying vertebral body compared with initial CT. We evaluated patient characteristics including body mass index, smoking history, fusion level, and cage type. A total of 113 patients underwent PLIF/TLIF (PLIF n = 30, TLIF n = 83), with a mean age of 71.1 years (range, 28–87 years). Mean duration of follow-up was 25 months (range, 12–47 months). Results Cage migration was identified in 5 of 113 patients (4.4%). All cases of symptomatic cage migration involved the L5/S1 level and the TLIF procedure. Risk factors for cage protrusion were age (younger), sex (male), and level (L5/S1). The mean duration to onset of cage protrusion was 3.2 months (range, 2–6 months). We applied a new classification for cage protrusion: type 1, only low back pain without new radicular symptoms; type 2, low back pain with minor radicular symptoms; or type 3, cauda equina syndrome and/or severe radicular symptoms. According to our classification, one patient was in type 1, three patients were in type 2, and one patient was in type 3. For all cases of cage migration, revision surgery was performed using a navigated high-speed burr and osteotome, and the patient in group 1 underwent additional PLIF without removal of the protruding cage. Three revision surgeries (group 2) involved removal of the protruding cage and PLIF, and one revision surgery (group 3) involved anterior removal of the cage and OLIF51 fusion. Conclusions The navigated high-speed burr, navigated osteotome, and OLIF51 technique appear very useful for removing a cage with fibrous union from the disc in patients with pseudarthrosis. This new technique makes revision surgery after cage migration much safer, and more effective. This technique also reduces the need for fluoroscopy.

Summary: Inflammatory stimuli cause a state of emergency myelopoiesis leading to neutrophil-like monocyte expansion. However, their function, the committed precursors, or growth factors remain elusive. In this study we find that Ym1+Ly6Chi monocytes, an immunoregulatory entity of neutrophil-like monocytes, arise from progenitors of neutrophil 1 (proNeu1). Granulocyte-colony stimulating factor (G-CSF) favors the production of neutrophil-like monocytes through previously unknown CD81+CX3CR1lo monocyte precursors. GFI1 promotes the differentiation of proNeu2 from proNeu1 at the cost of producing neutrophil-like monocytes. The human counterpart of neutrophil-like monocytes that also expands in response to G-CSF is found in CD14+CD16− monocyte fraction. The human neutrophil-like monocytes are discriminated from CD14+CD16− classical monocytes by CXCR1 expression and the capacity to suppress T cell proliferation. Collectively, our findings suggest that the aberrant expansion of neutrophil-like monocytes under inflammatory conditions is a process conserved between mouse and human, which may be beneficial for the resolution of inflammation.

Chromosome 15q26-qter deletion syndrome is a rare disease that causes prenatal and postnatal growth retardation, microcephaly, developmental delay, and congenital heart diseases, mainly due to haploinsufficiency of IGF1R. In addition, patients with pathogenic variants of the IGF1R show similar symptoms. We report the case of a 5-month-old girl with prenatal and postnatal growth retardation, microcephaly, and congenital heart disease. At 5 months of age, her length was 54.7 cm (−4.3 SD), her weight was 4.4 kg (−3.1 SD), and her head circumference was 37.4 cm (−2.8 SD), thus presenting severe growth retardation. Repeated pre-feeding serum GH levels were abnormally high (26.1–85.5 ng/mL), and IGF-1 levels (+0.16 to +1.2 SD) were relatively high. The 15q sub-telomere fluorescence in situ hybridization analysis revealed a heterozygous deletion in the 15q terminal region. Whole-genome single nucleotide polymorphism microarray analysis showed a terminal deletion of 6.4 Mb on 15q26.2q26.3. This is the first report showing that fasting GH levels are high in early infancy in patients with IGF1R abnormalities. In addition to relatively high IGF-1 levels, elevated fasting GH levels in early infancy may contribute to the diagnosis of IGF1R abnormalities.

Introduction: The loco-check is a simple tool for evaluating locomotive syndrome (LS), and a previous report suggested that it can be used to identify patients with stage 2 LS. The purpose of this study was to investigate the improvement in LS stage after surgery based on the loco-check in elderly patients with lumbar spinal stenosis (LSS) and to clarify the characteristics associated with improvement to non-stage 2 LS. Methods: We reviewed 40 elderly patients with LSS who underwent surgery at our institution. We compared the pre- and postoperative Japanese Orthopaedic Association score, loco-check, Oswestry Disability Index, EuroQoL-5 dimension utility values, and the EuroQoL-visual analog scale. We divided patients according to the presence or absence of stage 2 LS after surgery and compared their preoperative clinical findings and assessment measures. Results: Ninety percent of all patients had been preoperatively diagnosed with stage 2 LS according to the loco-check. After surgery, patients showed a decreased number of affirmative answers on the loco-check, according to which only 65% were postoperatively diagnosed with stage 2 LS. The receiver operating characteristic curve analysis identified less than four affirmative answers on the loco-check before LSS as predictive of improvement to non-stage 2 LS. Conclusions: Surgical treatment for elderly patients with LSS could improve LS. In patients with less than four affirmative answers on the loco-check preoperatively, improvement to non-stage 2 LS status may be possible.

C-type lectin receptors (CLRs) elicit immune responses upon recognition of glycoconjugates present on pathogens and self-components. While Dectin-1 is the best-characterized CLR recognizing β-glucan on pathogens, the endogenous targets of Dectin-1 are not fully understood. Herein, we report that human Dectin-1 is a ligand for CLEC-2, another CLR expressed on platelets. Biochemical analyses revealed that Dectin-1 is a mucin-like protein as its stalk region is highly O-glycosylated. A sialylated core 1 glycan attached to the EDxxT motif of human Dectin-1, which is absent in mouse Dectin-1, provides a ligand moiety for CLEC-2. Strikingly, the expression of human Dectin-1 in mice rescued the lethality and lymphatic defect resulting from a deficiency of Podoplanin, a known CLEC-2 ligand. This finding is the first example of an innate immune receptor also functioning as a physiological ligand to regulate ontogeny upon glycosylation.

Background and Objectives: C-arm-free MIS techniques can offer significantly reduced rates of postoperative complications such as inadequate decompression, blood loss, and instrumentation misplacement. Another advantageous long-term aspect is the notably diminished exposure to radiation, which is known to cause malignant changes. This study emphasizes that, in some cases of spinal conditions that require a procedural intervention, C-arm-free MIS techniques hold stronger indications than open surgeries guided by image intensifiers. Materials and Methods: This study includes a retrospective analysis and review of various cervical and thoracic spinal procedures, performed in our hospital, applying C-arm-free techniques. The course of this study explains the basic steps of the procedures and demonstrates postoperative and intraoperative results. For anterior cervical surgery, we performed OPLL resection, while for posterior cervical surgery, we performed posterior fossa decompression for Chiari malformation, minimally invasive cervical pedicle screw fixation (MICEPS), and modified Goel technique with C1 lateral mass screw for atlantoaxial subluxation. Regarding the thoracic spine, we performed anterior correction for Lenke type 5 scoliosis and transdiscal screw fixation for diffuse idiopathic skeletal hyperostosis fractures. Results: C-arm-free techniques are safe procedures that provide precise and high-quality postoperative results by offering sufficient spine alignment and adequate decompression depending on the case. Navigation can offer significant assistance in the absence of normal anatomical landmarks, yet the surgeon should always appraise the quality of the information received from the software. Conclusions: Navigated C-arm-free techniques are safe and precise procedures implemented in the treatment of surgically demanding conditions. They can significantly increase accuracy while decreasing operative time. They represent the advancement in the field of spine surgery and are hailed as the future of the same.

Abstract Designer receptor activated by designer drugs (DREADDs) techniques are widely used to modulate the activities of specific neuronal populations during behavioural tasks. However, DREADDs-induced modulation of histaminergic neurons in the tuberomamillary nucleus (HATMN neurons) has produced inconsistent effects on the sleep–wake cycle, possibly due to the use of Hdc-Cre mice driving Cre recombinase and DREADDs activity outside the targeted region. Moreover, previous DREADDs studies have not examined locomotor activity and aggressive behaviours, which are also regulated by brain histamine levels. In the present study, we investigated the effects of HATMN activation and inhibition on the locomotor activity, aggressive behaviours and sleep–wake cycle of Hdc-Cre mice with minimal non-target expression of Cre-recombinase. Chemoactivation of HATMN moderately enhanced locomotor activity in a novel open field. Activation of HATMN neurons significantly enhanced aggressive behaviour in the resident–intruder test. Wakefulness was increased and non-rapid eye movement (NREM) sleep decreased for an hour by HATMN chemoactivation. Conversely HATMN chemoinhibition decreased wakefulness and increased NREM sleep for 6 h. These changes in wakefulness induced by HATMN modulation were related to the maintenance of vigilance state. These results indicate the influences of HATMN neurons on exploratory activity, territorial aggression, and wake maintenance.

Abstract Background Our previous studies reveal that CCL18-CCR8 chemokine axis is upregulated in patients of immunoglobulin G4-related disease (IgG4-RD), suggesting that the CCL18–CCR8 axis is implicated in the etiology of IgG4-RD, although whether this axis has a potential as a therapeutic target remains unclear. Our purpose was to clarify the pathogenic roles and therapeutic potential of the murine CCL8 (analog of human CCL18)–CCR8 axis by using an animal model of IgG4-RD (LAT Y136F knockin mice; LAT mice). Methods We compared the infiltration of inflammatory cells and the fibrosis of the salivary glands of 6-week-old LAT mice and littermate mice. The expressions of Ccl8 and Ccr8 were also compared. Next, we investigated the therapeutic effects of intravenous administration of anti-CCL8 neutralizing antibody in LAT mice against inflammation and fibrosis of the salivary glands. We also investigated the effects of stimulation with recombinant mouse CCL8 on the collagen production in a mouse fibroblast cell line (NIH/3 T3) in vitro. Results When compared with the littermates, the LAT mice showed apparent infiltration of inflammatory cells and fibrosis in the salivary glands. The focus and fibrosis score in the salivary glands were significantly higher in the LAT mice than in the littermates. The expression levels of Ccl8 in the spleen and of Ccr8 in the salivary glands were significantly higher in the LAT mice than in the littermates. Anti-CCL8 antibody significantly improved the focus and fibrosis score in the salivary glands of the LAT mice. In vitro, stimulation with recombinant mouse CCL8 significantly increased the expression of collagen and ERK1/2 phosphorylation in NIH/3 T3. Conclusion We clarified the overexpression and therapeutic potential of the mouse CCL8–CCR8 axis in LAT mice, which could play a crucial role in fibrosis via ERK1/2 phosphorylation, as well as the chemotaxis of inflammatory cells. The human CCL18–CCR8 axis might be a novel therapeutic target for IgG4-RD.

Introduction: Compared with the conventional posterior lumbar decompression surgery, the spinous process splitting approach for lumbar spinal stenosis is less invasive. There are currently two types of the spinous process splitting approach that are performed. First is the lumbar spinous process splitting laminectomy (LSPSL), which involves the detachment of the spinous process from the lamina. Second is the modified Marmot method, which involves leaning of the spinous process without detachment from the lamina. To the best of our knowledge, this is the first study comparing the 2-year surgical outcomes of the modified Marmot method and LSPSL in cases of lumbar spinal canal stenosis. Methods: We recruited 69 patients who underwent decompression surgery. A total of 32 patients underwent the modified Marmot method (M group), and 37 patients underwent LSPSL (S group). We compared the clinical results, laboratory data of surgical invasion, wound pain, and safety. Results: No significant difference was observed in terms of the demographic data and operative time between the two groups. The number of decompressed segments and intraoperative and postoperative blood loss volume in the M group were greater than that in the S group. In the S group, the postoperative Japanese Orthopedic Association scores and recovery rates were significantly greater compared with those in the M group. Perioperative complications did not significantly differ between the two groups. On postoperative day 1, the Postoperative Visual Analog Scale scores at rest in the M group were lower than those in the S group. Conclusions: In clinical practice, we believe that posterior lumbar decompression surgery is safe, effective, and minimally invasive. Although the modified Marmot method may be less invasive and result in the reduction of wound pain during early postoperative periods, the clinical results did not exhibit greater long-term improvements with regard to surgical complications and neurological improvement, when compared with LSPSL.

Background: Retro-odontoid pseudotumor (ROPT) is a non-neoplastic pathology of the craniovertebral junction that is usually associated with atlantoaxial instability. The mass compresses the spinal cord, causing cervical myelopathy and potentially resulting in severe disability. Posterior atlantoaxial fixation without laminectomy is a suitable surgical option when the symptoms are mild and the static compression is moderate. In the setting of patients with severe symptoms and large ROPTs, posterior decompression becomes necessary. However, achieving solid posterior atlantoaxial fusion is difficult without a bony surface, namely the C1 posterior arch. Here, we describe a novel technique of C1 laminoplasty to achieve C1 decompression, and posterior atlantoaxial fusion with a modified Goel technique. Methods: An 83-year-old man was referred to our orthopedic department with quadriplegia due to atlantoaxial instability. His daily life had been affected by severe neck pain, clumsiness of bilateral hands, and gait disturbance for more than 2 years. Preoperative cervical radiograms revealed atlantoaxial instability, and magnetic resonance imaging showed a large pseudotumor compressing to the spinal cord. Results: The patient underwent C1 laminoplasty to decompress the spinal cord and retain the posterior arch as a bony surface for grafting and posterior atlantoaxial fusion. The procedure was well tolerated. The patient’s quadriparesis was improved and his Japanese Orthopedic Association score improved from 9/17 to 15/17 and his visual analog scale score for neck pain improved from 75 mm to 28 mm at the 1-year follow-up. Conclusion: C1 laminoplasty and posterior atlantoaxial fusion appears useful when C1 decompression and atlantoaxial fusion become necessary.

Background: Adult spinal deformity (ASD) is caused by spinal malalignment and results in severe low back pain, neurological dysfunction, and severe deformity. Surgical treatment, such as long spinal fusion offers improved patient-reported outcomes compared to conservative treatment. However, surgical complication of proximal screw pullout represents a difficult problem in minimally invasive ASD surgery. We describe a novel technique to prevent screw pullout in ASD. Case presentation: A 71-year-old woman was referred to our hospital with severe low back pain and gait difficulty. Her daily life had been affected by severe lower back pain for more than 6 months. Standing radiograms indicated severe kyphoscoliosis. Two-stage minimally invasive corrective T10-to-pelvis fixation was performed. The first surgery was an L1–S1 image-guided oblique lumbar interbody fusion, with an operation time of 3 h 57 min and an estimated blood loss of 240 mL. After 1 week, the second percutaneous pedicle screw (PPS) fixation was performed and proximal screws were inserted under a transdiscal approach (T11) and with a lower angulation trajectory (T10) to enhance pullout strength. For this second surgery, operation time was 3 h 33 min, and estimated blood loss was 320 mL. No postoperative complications or neurological compromise was reported. In terms of clinical outcomes, Oswestry Disability Index improved from 56% to 24%, and visual analog scale score for lower back pain improved from 62 mm to 24 mm at the 1-year follow-up. Conclusions: Minimally invasive circumferential surgery with triangular fixation is effective for preventing proximal screw back-out and surgical invasiveness. With this new technique, surgeons and operating room staff can avoid the risk of adverse events due to intraoperative radiation exposure.

Lumbar lateral interbody fusion (LLIF) has been gaining popularity among the spine surgeons dealing with degenerative spinal diseases while LLIF on L5-S1 is still challenging for its technical and anatomical difficulty. OLIF51 procedure achieves effective anterior interbody fusion based on less invasive anterior interbody fusion via bifurcation of great vessels using specially designed retractors. The technique also achieves seamless anterior interbody fusion when combined with OLIF25. A thorough understanding of the procedures and anatomical features is mandatory to avoid perioperative complications.

Abstract Background An important complication of pyogenic spondylitis is aneurysms in the adjacent arteries. There are reports of abdominal aortic or iliac aneurysms, but there are few reports describing infected aneurysms of the vertebral artery. Furthermore, there are no reports describing infected aneurysms of the vertebral arteries following cervical pyogenic spondylitis. We report a rare case of an infected aneurysm of the vertebral artery as a complication of cervical pyogenic spondylitis, which was successfully treated by endovascular treatment. Case presentation Cervical magnetic resonance imaging (MRI) of a 59-year-old man who complained of severe neck pain showed pyogenic spondylitis. Although he was treated extensively by antibiotic therapy, his neck pain did not improve. Follow-up MRI showed the presence of a cyst, which was initially considered an abscess, and therefore, treatment initially included guided tapping and suction under ultrasonography. However, under ultrasonographic examination an aneurysm was detected. The contrast-enhanced computed tomography (CT) scan showed an aneurysm of the vertebral artery. Following endovascular treatment (parent artery occlusion: PAO), the patient’s neck pain disappeared completely. Conclusion Although there are several reports of infected aneurysms of the vertebral arteries, this is the first report describing an infected aneurysm of the vertebral artery as a result of cervical pyogenic spondylitis. Whenever a paraspinal cyst exist at the site of infection, we recommend that clinicians use not only X-ray, conventional CT, and MRI to examine the cyst, but ultrasonography and contrast-enhanced CT as well because of the possibility of an aneurysms in neighboring blood vessels. It is necessary to evaluate the morphology of the aneurysm to determine the treatment required.

A filter circuit is required to suppress noise and have high gain attenuation characteristics in a wide band. Gain attenuation decreases because the relative permeability of an inductor core employed in a filter circuit drops sharply as drive frequency increases. Thus, by combining a core with a magnetic composite material with excellent frequency characteristics, we suppressed inductance reduction over a wide frequency range. As a result, the inductance of a hybrid inductor increased by 17.8% and 116% at 1 and 80 MHz, respectively, compared with that of a conventional inductor. When we applied a hybrid inductor to a Pi filter circuit, it was attenuated by 6.5 and 5.0 dB at 100 and 80 MHz, respectively, compared with a conventional inductor.

Abstract Background Neoplastic spinal cord compression is a cause of severe disability in cancer patients. To prevent irreversible paraplegia, a structured strategy is required to address the various impairments present in cancer patients. In this study, we aimed to identify the status where rehabilitation with minimally invasive spine stabilization (MISt) effectively improves ADL. Methods We retrospectively reviewed 27 consecutive patients with neoplastic spinal compression who were treated with MISt. We classified the impairments of patients through our multidisciplinary tumor board based on spine-specific factors, skeletal instability, and tumor growth. The neurological deficits, progress of pathological fracture, incidence of vertebral collapse, and postoperative implant failure were examined. Changes of the Barthel index (BI) scores before and after surgery were investigated throughout the clinical courses. Results The average duration to ambulation was 7.19 ± 11 days, and we observed no collapse or progression of paralysis except in four cases of complete motor paraplegia before the surgery. Neurological deficiency was improved to or maintained at Frankel’s grade E in 16 patients, remained unchanged in 6 patients (in grades B, C, D), and worsened in 5 patients. BI score comparisons before and after surgery in all patients showed statistically significant increments (p < 0.05). On further analysis, we noted good functional prognosis in patients capable of ambulation within 7 days (p < 0.05) and in patients who could survive longer than 3 months after the surgery (p < 0.05). Conclusions In various cancer patients with neoplastic spinal cord compression, skeletal instability as the primary impairment is a good indication for MISt, as the patients showed early ambulation with improved BI scores.

Study Design This is a retrospective clinical study. Purpose In this study, we aim to evaluate the reliability of the distal radius and ulna assessment (DRU) and simplified Tanner-Whitehouse III classification (sTW3) in Japanese patients with adolescent idiopathic scoliosis (AIS). Overview of Literature The greatest curvature of a scoliotic spine occurs at peak-height velocity (PHV), which is the time during which an individual’s height increases at the maximum rate. Diagnosing and appropriately treating AIS before PHV is the most effective way in order to prevent unnecessary deterioration of the scoliosis curve. Although it is difficult to detect scoliosis before PHV, DRU and sTW3, which involve evaluations using a left-hand radiograph, have been reported to be effective. Methods We retrospectively evaluated 54 hands of 40 girls with AIS who visited Nara Medical University Hospital from 2000 to 2015 using previously collected radiographs. The examiners included a spine surgeon and a pediatric orthopedic surgeon, each with over 10 years of experience. The reliability of the DRU and sTW3 was evaluated using the kappa coefficient. Results The left-hand radiographs of 40 female patients with AIS (mean age, 13.9±1.7 years; N=54 hands) were evaluated by two blinded examiners using the sTW3 and DRU methods. The highest inter-observer and intra-observer reliabilities (kappa, 0.64 and 0.62, respectively) for radius evaluation were determined. Radius evaluation by the DRU showed the highest agreement rate and smallest error between the inter- and intra-observer examinations. Conclusions The DRU was the most reliable assessment tool, and it has the potential to be useful for precisely determining the stage of skeletal maturity in outpatient clinics.

Background: Indirect decompression for lumbar canal stenosis as a technique of minimally invasive surgery (MIS), is receiving considerable attention. Conventional MIS indirect decompression at L5-S1 is performed using intraoperative fluoroscopy. In this work, we describe a novel C-arm free simultaneous MIS indirect decompression technique for L5-S1 pathology. Methods: A 72-year-old woman with symptomatic L5 isthmic spondylolisthesis was referred to our hospital. The patient’s daily life had been affected by severe low back pain for 5 years and left leg pain for 2 years. The surgery was performed without C-arm fluoroscopy. The percutaneous pedicle screws and intervertebral cages were inserted only under navigation guidance in a single lateral position. Results: The patient was successfully treated with surgery. Her low back pain and left leg pain improved dramatically. Her clinical outcomes, the Oswestry disability index (ODI) improved from 48% to 14% and the low back pain visual analog scale (VAS) score improved from 78 mm to 23 mm at 1 year of final follow-up. Conclusions: C-arm-free simultaneous MIS indirect decompression for L5-S1 is a useful technique, which may reduce surgical time and blood loss. With this new technique, surgeons and operation room staff can avoid the risk of an adverse event of intraoperative radiation.

Objective: This report aims to describe the surgical methodology and potential effectiveness of endoscopic separation surgery (ESS) in patients with metastatic spine disease. This concept may reduce the invasiveness of the procedure, which can potentially speed up the wound healing process and, thus, the possibility of faster application of radiotherapy. Materials and Methods: In this study, separation surgery for preparing patients for stereotactic body radiotherapy (SBRT) was performed with fully endoscopic spine surgery (FESS) followed by percutaneous screw fixation (PSF). Results: Three patients with metastatic spine disease in the thoracic spine were treated with fully endoscopic spine separation surgery. The first case resulted in the progression of paresis symptoms that resulted in disqualification from further oncological treatment. The remaining two patients achieved satisfactory clinical and radiological effects and were referred for additional radiotherapy. Conclusions: With advancements in medical technology, such as endoscopic visualization, and new tools for coagulation, we can treat more and more spine diseases. Until now, spine metastasis was not an indication for the use of endoscopy. This method is very technically challenging and risky, especially at such an early stage of application, due to variations in the patient’s condition, morphological diversity, and the nature of metastatic lesions in the spine. Further trials are needed to determine whether this new approach to treating patients with spine metastases is a promising breakthrough or a dead end.

Damage to the fascia can cause significant performance deficits in high-performance sports and recreational exercise and may contribute to the development of musculoskeletal disorders and persistent potential pain. The fascia is widely distributed from head to toe, encompassing muscles, bones, blood vessels, nerves, and internal organs and comprising various layers of different depths, indicating the complexity of its pathogenesis. It is a connective tissue composed of irregularly arranged collagen fibers, distinctly different from the regularly arranged collagen fibers found in tendons, ligaments, or periosteum, and mechanical changes in the fascia (stiffness or tension) can produce changes in its connective tissue that can cause pain. While these mechanical changes induce inflammation associated with mechanical loading, they are also affected by biochemical influences such as aging, sex hormones, and obesity. Therefore, this paper will review the current state of knowledge on the molecular level response to the mechanical properties of the fascia and its response to other physiological challenges, including mechanical changes, innervation, injury, and aging; imaging techniques available to study the fascial system; and therapeutic interventions targeting fascial tissue in sports medicine. This article aims to summarize contemporary views.

Background and Objectives: Adult spinal deformity (ASD) surgery, L5-S1 lordosis is very important factor. The main objective of the research is to retrospectively compare symptomatic presentation and radiological presentation in the sequelae of oblique lumbar inter-body spinal fusion at L5-S1 (OLIF51) and transforaminal lumbar interbody fusion (TLIF) for ASD. Materials and Methods: We retrospectively evaluated 54 patients who underwent corrective spinal fusion for ASD between October 2019 and January 2021. Thirteen patients underwent OLIF51 (average 74.6 years old, group O) and 41 patients underwent TLIF51 (average 70.5 years old, group T). Mean follow-up period was 23.9 months for group O and 28.9 months for group T, ranging from 12 to 43 months. Clinical and radiographic outcomes are assessed using values including visual analogue scale (VAS) for back pain and Oswestry disability index (ODI). Radiographic evaluation was also collected preoperatively and at 6, 12, and 24 months postoperatively. Results: Surgical time in group O was less than that in group T (356 min vs. 492 min, p = 0.003). However, intraoperative blood loss of both groups were not significantly different (1016 mL vs. 1252 mL, p = 0.274). Changes in VAS and ODI were similar in both groups. L5-S1 angle gain and L5-S1 height gain in group O were significantly better than those of group T (9.4° vs. 1.6°, p = 0.0001, 4.2 mm vs. 0.8 mm, p = 0.0002). Conclusions: Clinical outcomes were not significantly different in both groups, but surgical time in OLIF51 was significantly less than that in TLIF51. The radiographic outcomes showed that OLIF51 created more L5-S1 lordosis and L5-S1 disc height compared with TLIF 51.

Radiofrequency ablation (RFA) is a widely used and effective treatment for primary or metastatic liver cancer with small-size lesions. However, the therapeutic effectiveness of RFA in controlling metastatic lesion or recurrence is still limited. As the major cell population in tumor microenvironment (TME), macrophages have been reported to be recruited to RFA-treated lesion, but their roles are still unclear. Herein, we successfully established the mouse model mimicking RFA-induced abscopal effect, in which RFA eliminated the local orthotopic liver tumor but failed to control growth of distant tumor. Correspondently, RFA suppressed protumoral activation of local tumor-associated macrophages (TAMs), but failed to reprogram TAMs in distance. Importantly, although RFA led to reduced proportion of hepatic CD169+ macrophages in local and decreased expression of immune inhibitory molecules Tim-3 and PD-L1, these alterations were not observed for CD169+ macrophages in distant TME. Further RNA-seq and flow cytometry analysis showed that hepatic CD169+ macrophages contributed to reprograming TME through recruiting CD8+ T/NK cells and suppressing accumulation of MDSCs/Tregs. Consistently, depletion of CD169+ macrophages in CD169-DTR mouse greatly promoted liver tumor progression and largely dampened RFA-induced tumor suppression. Notably, transfer of CD169+ macrophages synergistically enhanced RFA-induced inhibition of distant tumor. To our knowledge, this is the first study which demonstrates hepatic CD169+ macrophages as a key factor responsible for RFA-induced abscopal effect. Our data suggest RFA with transfer of CD169+ macrophages as a promising combination therapy to lessen metastasis or recurrence of liver cancer in patients.

Background: Navigation surgery is becoming very popular for anterior cervical surgery. However, one difficult problem for anterior cervical surgery is setting the reference frame (RF), due to the lack of reliable structures. If the RF is attached to the head holder or operation table instead of the patient, the accuracy of navigation is not good. Materials and methods: This retrospective study included six patients who underwent anterior cervical surgeries with O-arm navigation. The RF was attached to the Caspar retractor using a special adaptor. Patients comprised three men and three women with a mean age of 62.8 years. Anterior cervical discectomy and fusion was performed in three cases, and anterior cervical corpectomy and fusion in three cases. We evaluated the accuracy of navigation, surgical time, intraoperative blood loss, complications, bony fusion, and clinical results. Results: Mean accuracy of anterior navigation was 1.1 ± 0.7 mm (range, 0–2 mm). Mean surgical time and blood loss were 166 ± 39 min (range, 121–359 min) and 280 ± 189 ml (range, 50–600 ml), respectively. Complications comprised one case of postoperative C5 palsy that recovered within 6 months. Mean Japanese Orthopedic Association (JOA) recovery rate was 52.4% (range, 20–100%). Adequate decompression and solid fusion were obtained in all cases. Conclusions: Intraoperative O-arm navigation-guided anterior cervical decompression and fusion is an effective technique for achieving precise decompression. This new navigation technique provides excellent results for severe cervical ossification of the posterior longitudinal ligament (OPLL) with minimum risk of adverse events from intraoperative radiation. We advocate the use of this novel technique in cases of cervical canal stenosis due to large disc osteophyte complex and OPLL, and also in cases of distorted cervical anatomy due to deformity, tumor, or revision surgery.

This is a prospective study that has been done to assess the lumbar sagittal alignment of patients positioned prone over an adjustable hinged carbon fiber operating table. The following three variations of table position have been considered: neutral, 20° convex, and 20° concave bending. A total of 33 patients who underwent lumbar disc herniation and lumbar canal stenosis surgery were enrolled. Patients who presented with spinal deformity akin to lumbar scoliosis or spondylolisthesis were excluded. For the surgical procedure, following the induction of endotracheal general anesthesia, patients were positioned prone on the adjustable hinged carbon fiber operating table. Radiographs of the lateral view of the lumbar spine were acquired for the three table positions, i.e., neutral, 20° convex, and 20° concave. The lumbar lordosis was measured on radiographs. The lumbar lordosis presented divergently in all three variations of the table (p < 0.01): 45.2 ± 11.0° in neutral; 52.0 ± 10.7° in 20° lumbar extension bending; and 35.9 ± 10.8° in 20° lumbar flexion bending. The efficacy of table bending was 46.5% in convex and 34.0% in concave bending. In conclusion, the lumbar lordosis in three different table positions were 35.9° in 20° convex bending, 45.2° in neutral, and 52.0° in concave bending. The efficacy of table bending was 46.5% in convex and 34.0% in concave bending.

Study design: Technical note. Objectives: To present a novel C-arm-free technique guided by navigation to insert and place a C1 lateral mass screw. Background and Objectives: Atlantoaxial subluxation (AAS) is a relatively common sequelae in patients with rheumatoid arthritis (RA) and upper cervical trauma. If they present with severe symptoms, surgical intervention such as posterior fusion is indicated. The established treatment for AAS is fixation with a C1 lateral mass screw and C2 pedicle screw (modified Goel technique) to achieve bony fusion. However, this technique requires fluoroscopy for C1 screw insertion. To avoid exposing the operating team to radiation, we present here a novel C-arm-free C1 lateral mass screw insertion technique for AAS. Materials and Methods: A 67-year-old man was referred to our hospital with neck pain, quadriparesis, and clumsiness and numbness of both upper and lower limbs. He had undergone C3–6 posterior fusion previously in another hospital. In physical examination, he had severe muscle weakness of bilateral upper limbs and hypoesthesia of all four limbs. He had hyper-reflexia of bilateral lower limbs and pollakiuria. His Japanese orthopedic score was 8 points out of 17. Preoperative radiograms showed AAS with an atlantodental interval (ADI) of 7 mm. MRI indicated retro-odontoid pseudotumor and severe spinal cord compression at the C1–2 level. The patient underwent posterior atlantoaxial fixation under navigation guidance. To prevent epidural bleeding during the insertion and placement of a C1 lateral mass screw, we have here defined a novel screw insertion technique. Results: The surgical time was clocked as 127 min and blood loss was 100 mL. There were no complications per-operatively or in the postoperative period. The patient showed almost full recovery (JOA 16/17) at two months follow-up and a solid bony fusion was noticed in the radiograms at one year follow-up. Conclusions: This novel surgical procedure and C1 lateral mas screw placement technique is a practical and safe method in recent advances of AAS treatment. Procedurally, the technique helps prevent epidural bleeding from the screw entry point and also allows for proper C1 screw insertion under navigation guidance without exposing surgeons and staff to the risk of fluoroscopic radiation.

Neutrophil extracellular traps (NETs) are web-like structures consisting of decondensed chromatin DNA and contents of granules, such as myeloperoxidase (MPO) and neutrophil elastase (NE). NETs are usually released from neutrophils undergoing NETosis, a neutrophil-specific cell death mode characterized by the collapse and disappearance of cell membranes and nuclear envelopes. It is well known that production of reactive oxygen species (ROS) triggers NETosis and NET formation. However, details of intracellular signaling downstream of ROS production during NETosis and NET formation remains uncertain. Here, we demonstrated that the peroxidation of phospholipids plays a critical role in NETosis and NET formation induced by phorbol 12-myristate13-acetate (PMA) or immune complex in vitro and by lipopolysaccharide (LPS) in vivo. This phospholipid peroxidation is mediated by the enzymatic activity of MPO. On the other hand, NE, which was previously reported to be released from granules to cytosol by MPO during NET formation, is not required for either the peroxidation of phospholipids or the execution of NETosis, but contributes to chromatin decondensation and nuclear swelling independently of MPO-mediated oxidized phospholipids. Analysis of isolated nuclei clearly demonstrated that oxidized phospholipids and NE differently yet synergistically execute chromatin decondensation and nuclear swelling, and the subsequent release of nuclear contents. These findings indicate the dual roles of MPO in NETosis and NET formation, and provide new insight into the molecular mechanism of these phenomena.

Study design: Retrospective comparative study. Objective: Comparative study of C-arm free O-arm navigated minimally invasive cervical pedicle screw (MICEPS) fixation with conventional cervical pedicle screw fixation. Methods: Twenty-five patients with different cervical spine pathologies were operated with MICEPS with O-arm navigation (group M; 18 patients) and conventional pedicle screw (group C; 7 patients) from June 2017 to January 2020. Operative time, blood loss were recorded. Preoperative and postoperative radiograms, CT scans and MRI were evaluated. Postoperatively screw position accuracy and angulation was determined on CT. Breach rate was evaluated on CT scan and classified according to Neo grading. Complications if any were noted. Results: The average blood loss in group M and group C was 129 ml and 329 ml, respectively. The average operative time in group M and group C was 77.4 min and 82.3 min, respectively. A total of 148 screws were inserted. In group M, no patient showed grade 2 and 3 breach while in group C, grade 0 and 1 breach was found in 85.7% screws and grade 2 in 14.3% screws. Mean screw medial angulation was 45.2 degrees in group M and 33.4 degrees in group C. There was one dural tear and two C5 palsies in each group. Conclusion: With C -arm free O-arm navigated MICEPS fixation operative time and blood loss are less though not statistically significant. It has less pedicle breach rate, less incidence of neurovascular complications than conventional technique. There is no radiation exposure to operating surgeon and staff.

Background: Percutaneous pedicle screw (PPS) fixation as a minimally invasive surgery (MIS) is becoming the standard method for stabilizing thoracolumbar burst fractures. However, with the conventional PPS percutaneous reduction is difficult, and a great amount of usage of fluoroscopy is necessary. We describe a novel technique of C-arm free PPS with new reduction device for thoracolumbar fractures. Methods: A 22-year-old man presented to our hospital with severe low back pain and impending paraplegia secondary to T12 burst fracture. We performed short-segment fixation and reduction for this patent. The special PPS which have reduction mechanism were inserted under O-arm navigation guidance. The trauma reduction system was applied and the fracture was reduced without fluoroscopy. Results: Postoperative computed tomography (CT) showed the adequate screws position and complete reduction of the vertebral body. On one-year follow-up, the patient was asymptomatic, with the fracture healed and no implant loosening. Conclusions: C-arm free PPS and reduction is a useful MIS technique for thoracolumbar burst fractures.

Background: Surgical management of spondyloptosis (grade 5 spondylolisthesis) is challenging and controversial, from in situ fusion to complete reduction. In situ fusion is less technically demanding and offers the advantage of a low risk of neurological complications, but the pseudoarthrosis rate is high and sagittal alignment cannot be normalized. We present a relatively rare case of a patient with L5 spondyloptosis who needed revision surgery due to psuedoarthrosis and rod breakage. Case description: A 12-year-old girl with L5 spondyloptosis was referred to our hospital. She had a 3-year history of low back pain (visual analogue scale: VAS 8/10), bilateral L5 dermatomal pain (VAS 6/10) and paresthesia. The patient was successfully treated with surgery, partial reduction was performed and sagittal and coronal alignments were normalized. But at 1.5 year follow up, patient presented with low back pain, rod breakage and psuedoarthrosis, so revision surgery was done with fibula grafting, dual sacro-alar-iliac screws and additional rod. At the 3-year follow-up, VAS for low back pain had improved from 8/10 to 2/10 and leg pain had disappeared. Postoperative radiograms at final follow-up revealed no loss of reduction or loosening of implants. Conclusions: Sagittal reduction is more important than horizontal reduction for patients with spondyloptosis showing sagittal malalignment (SDSG type 5 or 6). Cantilever and table-bending techniques are useful to obtain good sagittal alignment for patients showing spondyloptosis. It is important to have circumferential fusion if reduction is aimed.

Systemic and local inflammation associated with therapeutic intervention of primary tumor occasionally promotes metastatic recurrence in mouse and human. However, it remains unclear what types of immune cells are involved in this process. Here, we found that the tissue-repair-promoting Ym1+Ly6Chi monocyte subset expanded as a result of systemic and local inflammation induced by intravenous injection of lipopolysaccharide or resection of primary tumor and promoted lung metastasis originating from circulating tumor cells (CTCs). Deletion of this subset suppressed metastasis induced by the inflammation. Furthermore, transfer of Ym1+Ly6Chi monocytes into naïve mice promoted lung metastasis in the mice. Ym1+Ly6Chi monocytes highly expressed matrix metalloproteinase-9 (MMP-9) and CXCR4. MMP-9 inhibitor and CXCR4 antagonist decreased Ym1+Ly6Chi-monocyte-promoted lung metastasis. These findings indicate that Ym1+Ly6Chi monocytes are therapeutic target cells for metastasis originating from CTCs associated with systemic and local inflammation. In addition, these findings provide a novel predictive cellular biomarker for metastatic recurrence after intervention for primary tumor.

Background: Anterior cervical corpectomy and fusion (ACCF) with floating technique is one of the best surgical interventions for severe ossification of the posterior longitudinal ligament (OPLL). However, insufficient decompression and a thinned ossification mass often lead to poor clinical outcome. This report describes a novel floating technique with intraoperative O-arm navigation to facilitate surgical treatment of the OPLL, which has not previously been described as a therapeutic option. Case description: An 82-year-old woman with myelopathy of the OPLL was referred to our hospital. Activities of daily living had been restricted by severe left arm pain, myelopathy hand, and gait disturbance for 3 years. ACCF was performed under the guidance of O-arm navigation and C-arm-free minimally invasive cervical pedicle screw fixation (MICEPS). The patient was successfully treated surgically and manual muscle test results and sensory function of the left arm had recovered fully by final follow-up at 1 year. Japanese Orthopedic Association score of the patient had improved from 10/17 to 16/17. Conclusions: Intraoperative O-arm navigation-guided ACCF with C-arm-free MICEPS is an effective technique for achieving precise decompression and strong, minimally invasive fixation. This new anterior navigation technique provides an excellent result for severe OPLL without the risk of adverse events from intraoperative radiation.