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Introduction: Pedicle screws are commonly used in fixation to treat various spinal disorders. However, screw loosening is a prevalent complication, particularly in patients with osteoporosis. Various biomechanical studies have sought to address this issue, but the optimal depth and trajectory to increase the fixation strength of pedicle screws remain controversial. Therefore, a biomechanical study was conducted using finite element models. Methods: Three-dimensional finite element models of the L3 vertebrae were developed from the preoperative computed tomography images of nine patients with osteoporosis and nine patients without who underwent spine surgery. Unicortical and bicortical pedicle screws were inserted into the center and into the anterior wall of the vertebrae, respectively, in different trajectories in the sagittal plane: straightforward, cephalad, and caudal. Subsequently, three different external loads were applied to each pedicle screw at the entry point: axial pullout, craniocaudal, and lateromedial loads. Nonlinear analysis was conducted to examine the fixation strength of the pedicle screws. Results: Irrespective of osteoporosis, the bicortical pedicle screws had greater fixation strength than the unicortical pedicle screws in all trajectories and external loads. The fixation strength of the bicortical pedicle screws was not substantially different among the trajectories against any external loads in the nonosteoporotic vertebrae. However, the fixation strength of the bicortical pedicle screws against craniocaudal load in the cephalad trajectory was considerably greater than those in the caudal (P=0.016) and straightforward (P=0.023) trajectories in the osteoporotic vertebrae. However, this trend was not observed in pullout and lateromedial loads. Conclusions: Our results indicate that bicortical pedicle screws should be used, regardless of whether the patient has osteoporosis or not. Furthermore, pedicle screws should be inserted in the cephalad trajectory in patients with osteoporosis.

Introduction: Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disorder that principally targets the central nervous system, specifically the spinal cord and optic nerves. NMOSD is often associated with thyroid pathologies such as Graves’ disease or Hashimoto’s thyroiditis. Thyroid eye disease (TED) is an autoimmune condition characterized by inflammation and hypertrophy of the extraocular muscles. Dysthyroid optic neuropathy (DON), a critical complication of TED, may lead to irreversible visual loss. We report a case of DON complicated by NMOSD. Case Presentation: We report a case of an autoimmune disease presenting as DON in a 44-year-old Japanese woman with a history of Graves’ disease, who experienced reduced visual acuity and orbital pain. Brain magnetic resonance imaging disclosed hypertrophy of the rectus muscles, compressing the optic nerve bilaterally. Consequently, she was diagnosed with DON and underwent three courses of steroid semi-pulse therapy and left orbital decompression surgery, alleviating optic nerve compression. Nevertheless, the visual prognosis remained poor. A subsequent serological test showed positive for aquaporin-4 antibody. Treatment with satralizumab, an interleukin-6 receptor monoclonal antibody, was initiated in conjunction with steroids to suppress the autoimmune response and reduce NMOSD relapse risk. Following this treatment, no NMOSD recurrences were reported. Conclusion: This case highlights the necessity of considering the possible coexistence of DON and NMOSD in patients with autoimmune diseases.

Introduction: This study aimed to compare the outcomes of corrective fusion for adult spinal deformity (ASD) in older people using two different sagittal correction goals: the conventional formula of “pelvic incidence (PI)-lumbar lordosis (LL) mismatch 20° or LL

Introduction: Postoperative spinal epidural hematoma (PSEH) is a severe complication of spinal surgery that necessitates accurate and timely diagnosis. This study aimed to assess the accuracy of ultrasonography as an alternative diagnostic tool for PSEH after microendoscopic laminotomy (MEL) for lumbar spinal stenosis, comparing it with magnetic resonance imaging (MRI). Methods: A total of 65 patients who underwent MEL were evaluated using both ultrasound- and MRI-based classifications for PSEH. Intra- and interrater reliabilities were analyzed. Furthermore, ethical standards were strictly followed, with spine surgeons certified by the Japanese Orthopaedic Association performing evaluations. Results: Among the 65 patients, 91 vertebral segments were assessed. The intra- and interrater agreements for PSEH classification were almost perfect for both ultrasound (κ=0.824 [95% confidence interval (CI) 0.729-0.918] and κ=0.810 [95% CI 0.712-0.909], respectively) and MRI (κ=0.839 [95% CI 0.748-0.931] and κ=0.853 [95% CI 0.764-0.942], respectively). The results showed high concordance between ultrasound- and MRI-based classifications, validating the reliability of ultrasound in postoperative PSEH evaluation. Conclusions: This study presents a significant advancement by introducing ultrasound as a precise and practical alternative to MRI for PSEH evaluation. The comparable accuracy of ultrasound to MRI, rapid bedside assessments, and radiation-free nature make it valuable for routine postoperative evaluations. Despite the limitations related to specific surgical contexts and clinical outcome assessment, the clinical potential of ultrasound is evident. It offers clinicians a faster, cost-effective, and repeatable diagnostic option, potentially enhancing patient care. This study establishes the utility of ultrasound in evaluating postoperative spinal epidural hematomas after MEL. With high concordance to MRI, ultrasound emerges as a reliable, practical, and innovative tool, promising improved diagnostic efficiency and patient outcomes. Further studies should explore its clinical impact across diverse surgical scenarios.

Ai Kozaki,&ast; Rishu Inoue,&ast; Naoko Yaji,&ast; Koichi Nishiyama,&ast; Toshu Inoue&ast; Olympia Eye Hospital, Tokyo, Japan&ast;These authors contributed equally to this workCorrespondence: Ai Kozaki, Olympia Eye Hospital, 2-18-12 Jingumae, Shibuya-ku, Tokyo, 150-0001, Japan, Tel +81-3-3746-8981, Fax +81-3-3746-8830, Email kouzaki@olympia.netPurpose: To evaluate the efficacy of subcutaneous injection of triamcinolone acetonide (SCTA) in treating upper eyelid retraction and swelling in patients with thyroid eye disease (TED).Patients and Methods: This case series included consecutive patients (aged 16– 69 years, monitored from June 2012 to December 2015) with TED-related eyelid symptom and without an enlarged extraocular muscle on magnetic resonance imaging (MRI). SCTA (0.5 mL, 40 mg/mL) was administered to target the orbital fat around the levator palpebrae superioris (LPS) muscle. Patients who did not exhibit improvement after the first trial received an additional injection. Follow-up was conducted for 12 months with 3-month intervals. Eyelid retraction, eyelid swelling, and eyelid lag were evaluated at each follow-up visit.Results: In total, 116 eyelids of 102 patients were analyzed. SCTA led to significant improvement in 93% of eyes (108/116), disappearance of eyelid symptoms (74%, 87%, and 73% in retraction, swelling, and lag, respectively), and improvement of scores (from 1.64 to 0.12, 1.32 to 0.26, and 1.72 to 0.30, respectively). Improvement in eyelid symptoms was observed in eight eyes; however, additional steroid therapy was required in these cases due to the emergence of other extraocular muscle inflammation. Additional injection was required in 39.8% of patients. The clinical activity score was lower in the single SCTA group than in the multiple SCTA group (1.5 vs 0.9; p < 0.01). However, the levels of thyroid-stimulating hormone receptor antibody and MRI findings were not significantly different between the two groups. No elevation in intraocular pressure was observed. Eight female patients experienced menstrual disorder.Conclusion: SCTA effectively reduced LPS muscle enlargement and fat tissue swelling in patients with TED. A single SCTA was sufficient in almost 60% of the patients; nevertheless, follow-up is necessary to detect early signs of orbital inflammation even in eyelid-symptom-improved patients.Keywords: Graves’ disease, triamcinolone injection, magnetic resonance imaging, levator palpebrae superioris muscle, inflammation

Abstract Background One of the common mechanical complications following spinal fusion surgery is proximal junctional failure (PJF). The incidence of neurological deficit associated with PJF has been poorly described in the literature. Here, we report a case in which numbness in the lower extremities was recognized as the first symptom, but the discrepancy in the imaging findings made PJF difficult to diagnose. Methods A 71-year-old female underwent corrective fusion surgery. Three weeks later, she complained of persistent right leg numbness. Standing X-ray showed the back-out of the pedicle screws (PSs) in the upper instrumented vertebra (UIV), but there was no obvious evidence of cord compression on computed tomography (CT), which caused the delay of diagnosis. Five weeks later, magnetic resonance image (MRI) did not show cord compression on an axial view, but there were signal changes in the spinal cord. Results The first reason for the delayed diagnosis was the lack of awareness that leg numbness could occur as the first symptom of PJF. The second problem was the lack of evidence for spinal cord compression in various imaging tests. Loosened PSs were dislocated on standing, but were back to their original position on supine position. In our case, these contradictory images led to a delay in diagnosis. Conclusion Loosened PSs caused dynamic cord compression due to repeated deviation and reduction. Supine and standing radiographs may be an important tool in the diagnosis of PJF induced by dynamic cord compression.

Appropriate administration of anti-inflammatory and immunosuppressive treatment (AIIST) is important for patients with Graves’ orbitopathy (GO). This study aimed to clarify the incidence and risk factors for GO treated with AIIST and propose a predictive score, among newly diagnosed Graves’ disease (GD) patients in Japan. A total of 1,553 GD patients who were newly diagnosed during the year 2011 were investigated. AIIST included local and/or systemic glucocorticoid administration and retrobulbar irradiation. A multivariable Cox proportional hazards model was used to investigate the risk factors for GO underwent AIIST during medical treatment, including at diagnosis, of GD. Then, a GO score was created by summing each point assigned to risk factors based on their coefficient obtained in the Cox model. AIIST was administered to 107 patients (6.9%). The risk factors and hazard ratios for GO underwent AIIST were: age (per 10 years), 1.32 (95% confidence interval: 1.16–1.50), p < 0.0001; TSH binding inhibitory immunoglobulin (TBII) (per 10 IU/L), 1.33 (1.15–1.54), p = 0.0001; and thyroglobulin antibody (TgAb) negativity, 2.98 (1.96–4.59), p < 0.0001. The GO score, ranging from 0 to 8 points, showed moderate performance (area under the curve: 0.71, cut-off value: 5 points, sensitivity: 0.76, specificity: 0.59, positive predictive value: 0.12, negative predictive value: 0.97). AIIST was performed for patients with active manifestations of GO in 6.9% of newly diagnosed GD patients. The risk factors for GO underwent AIIST were higher age, higher TBII, and TgAb negativity. The GO score based on these factors may be useful in managing GO.

Introduction: Despite the absence of bone grafting in the area outside the cage, lateral bridging callus outside cages (LBC) formation is often observed here following extreme lateral interbody fusion (XLIF) conversely to conventional methods of transforaminal lumbar interbody fusion and posterior lumbar interbody fusion. The LBC, which may increase stabilization and decrease nonunion rate in treated segments, has rarely been described. This study aimed to identify the incidence and associated factors of LBC following XLIF. Methods: We enrolled 136 consecutive patients [56 males, 80 females; mean age 69.6 (42-85) years] who underwent lumbar fusion surgery using XLIF, including L4/5 level with posterior fixation at a single institution between February 2013 and February 2018. One year postoperatively, the treated L4/5 segments were divided into the LBC formation and non-formation groups. Potential influential factors, such as age, sex, body mass index, bone density, height of cages, cage material (titanium or polyetheretherketone [PEEK]), presence or absence of diffuse idiopathic skeletal hyperostosis (DISH), and radiological parameters, were evaluated. Multivariate logistic regression analysis was performed for factors significantly different from the univariate analysis. Results: The incidence of LBC formation was 58.8%. Multivariate logistic regression analysis showed that the length of osteophytes [+1 mm; odds ratio, 1.29; 95% confidence interval, 1.17-1.45; p

Abstract Background The present study aimed to examine the association between the conditioning intensity and height growth in pediatric patients who underwent allogeneic hematopoietic stem cell transplantation (allo‐HSCT). Methods We reviewed the clinical records of 89 children with malignant diseases who underwent initial allo‐HSCT between 2003 and 2021. Height measurements were standardized using standard height charts prepared by the Japanese Society for Pediatric Endocrinology to calculate standard deviation score (SDS). We defined short stature as a height SDS less than −2.0 in that reference. Myeloablative conditioning (MAC) comprised total‐body irradiation at more than 8 Gy and busulfan administration at more than 8 mg/kg (more than 280 mg/m2). Other conditioning regimens were defined as reduced intensity conditioning (RIC). Results A total of 58 patients underwent allo‐HSCT with MAC, and 31 patients received allo‐HSCT with RIC. There were significant differences in the height SDS at 2 and 3 years after allo‐HSCT between MAC and RIC group (−1.33 ± 1.20 vs. −0.76 ± 1.12, p = 0.047, −1.55 ± 1.28 vs. −0.75 ± 1.11, p = 0.022, respectively). Multivariate logistic regression analysis with the adjustments for potential confounding factors of patients less than 10 years of age at allo‐HSCT and chronic graft‐versus host disease demonstrated that MAC regimen was associated with a markedly increased risk of a short stature at 3 years after allo‐HSCT (adjusted odds ratio, 5.61; 95% confidence interval, 1.07–29.4; p = 0.041). Conclusion The intensity of conditioning regimen may be associated with short statures after allo‐HSCT.

Visual motion signals can produce self-motion perception known as vection in observers. Vection can be generated by illusory motions in the form of global expantion in still images as well as by visual motion signals. The perception of vection can be enhanced by flickering images at a rate of 5 Hz. This study examined the illusory motion and vection induced by a printed static image under flickering ambient light at rates up to 100 Hz. The perception of illusory motion and vection were enhanced by flickering ambient lights at 50, 75, and 100 Hz. The enhancement effect was higher for the flicker rates expected to be detectable by humans. The findings of this study suggest that alternating bright and dark signals to the cone receptors and primary visual cortex trigger perceptions of illusory motions.

Introduction: Mechanical complications, such as rod fracture (RF) and proximal junctional kyphosis (PJK), commonly occur after adult spinal deformity (ASD) surgery. A rigid construct is preferred to prevent RF, whereas it is a risk factor for PJK. This controversial issue urged us to conduct a biomechanical study for seeking the optimal construct to prevent mechanical complications. Methods: A three-dimensional nonlinear finite element model, which consisted of the lower thoracic and lumbar spine, pelvis, and femur, was created. The model was instrumented with pedicle screws (PSs), S2-alar-iliac screws, lumbar interbody fusion cages, and rods. Rod stress was measured when a forward-bending load was applied at the top of the construct to evaluate the risk of RF in constructs with or without accessory rods (ARs). In addition, fracture analysis around the uppermost instrumented vertebra (UIV) was performed to assess the risk of PJK. Results: Changing the rod material from titanium alloy (Ti) to cobalt chrome (CoCr) decreased shearing stress at L5-S1 by 11.5%, and adding ARs decreased it by up to 34.3% (for the shortest ARs). Although the trajectory (straightforward vs. anatomical) of PSs did not affect the fracture load for UIV+1, changing the anchor from PSs to hooks at the UIV reduced it by 14.8%. Changing the rod material from Ti to CoCr did not alter the load, whereas the load decreased by up to 25.1% as the AR became longer. Conclusions: The PSs at the UIV in the lower thoracic spine, CoCr rods as primary rods, and shorter ARs should be used in long fusion for ASD to prevent mechanical complications.

Abstract Background This study aimed to determine the feasibility of ultrasonography in the assessment of cervical vertebral artery (VA) injury as an alternative to computed tomography angiography (CTA) in the emergency room. Methods We analyzed 50 VAs from 25 consecutive patients with cervical spine injury that had been admitted to our emergency room. Ultrasonography and CTA were performed to assess the VA in patients with cervical spine injury. We examined the sensitivity and specificity of ultrasonography compared with CTA. Results Among these VAs, six were occluded on CTA. The agreement between ultrasonography and CTA was 98% (49/50) with 0.92 Cohen's Kappa index. The sensitivity, specificity, and positive and negative predictive values of ultrasonography were 100%, 97.7%, 85.7%, and 100%, respectively. In one case with hypoplastic VA, the detection of flow in the VA by ultrasonography differed from detection by CTA. Meanwhile, there were two cases in which VAs entered at C5 transverse foramen rather than at C6 level. However, ultrasonography could detect the blood flow in these VAs. Conclusions Ultrasonography had a sensitivity of 100% compared with CTA in assessment of the VA. Ultrasonography can be used as an initial screening test for VA injury in the emergency room.

We report on the activities of the 2015 edition of the BioHackathon, an annual event that brings together researchers and developers from around the world to develop tools and technologies that promote the reusability of biological data. We discuss issues surrounding the representation, publication, integration, mining and reuse of biological data and metadata across a wide range of biomedical data types of relevance for the life sciences, including chemistry, genotypes and phenotypes, orthology and phylogeny, proteomics, genomics, glycomics, and metabolomics. We describe our progress to address ongoing challenges to the reusability and reproducibility of research results, and identify outstanding issues that continue to impede the progress of bioinformatics research. We share our perspective on the state of the art, continued challenges, and goals for future research and development for the life sciences Semantic Web.