1.Impact of car seat recline angle on global spinal alignment and seat belt positioning: a prospective observational study in Japan
Norihiro NISHIDA ; Tomohiro IZUMIYAMA ; Ryusuke ASAHI ; Hidenori SUZUKI ; Masahiro KOIKE ; Masahiro FUNABA ; Kazuhiro FUJIMOTO ; Yusuke ICHIHARA ; Yogesh KUMARAN ; Hiroshi HAMANO ; Shigeru SUGIMOTO ; Takashi SAKAI
Asian Spine Journal 2026;20(2):283-293
Methods:
Lateral radiographs were obtained from 100 healthy adults in standing and seated postures at 25°, 35°, and 45° recline angles. Spinal parameters (cervical lordosis, thoracic kyphosis, thoracolumbar kyphosis, lumbar lordosis, sacral slope, pelvic tilt, and T1 spinopelvic inclination) and seat belt metrics (X-value, Z-value, and lap belt angle) were measured. Multivariate regression was used to assess associations with sex, age, height, and body mass index (BMI).
Results:
Reclining reduced cervical/lumbar lordosis and sacral slope, while thoracic kyphosis and pelvic tilt increased. Higher BMI was associated with a cranially shifted and more horizontal lap belt. Taller individuals showed greater T1 spinopelvic inclination and pelvic parameters. Females exhibited more pronounced thoracic kyphosis and pelvic retroversion across reclining angles.
Conclusions
Car seat recline significantly alters spinal alignment and seat belt positioning, with changes influenced by age, height, and BMI. These findings support ergonomic improvements in seat design and may inform surgical planning for ASD.
2.Correlation between postoperative shoulder imbalance and distal adding-on and distal junctional kyphosis in Lenke type 2 adolescent idiopathic scoliosis: a retospective study
Norihiro ISOGAI ; Satoshi SUZUKI ; Nao OTOMO ; Yohei TAKAHASHI ; Masahiro OZAKI ; Toshiki OKUBO ; Osahiko TSUJI ; Narihito NAGOSHI ; Mitsuru YAGI ; Masaya NAKAMURA ; Morio MATSUMOTO ; Kota WATANABE
Asian Spine Journal 2026;20(2):272-282
Methods:
This study included 62 patients with Lenke type 2 AIS who underwent posterior correction and fusion surgeries. The patients were categorized into the PSI and non-PSI groups based on their radiographic shoulder height 2 years after surgery. Radiographic parameters, lower end vertebra (LEV), lower instrumented vertebra (LIV), sagittal stable vertebra (SSV), postoperative DA and DJK, and Scoliosis Research Society 22 scores were compared between the two groups using unpaired t -tests or Pearson’s chi-square tests.
Results:
Twenty-eight patients in the PSI group and 34 in the non-PSI group were evaluated. Three patients had DA in the PSI group and 10 with DA and four with DJK in the non-PSI group. LIV–LEV was higher in the PSI group than in the non-PSI group. Although the LIV–SSV was not significantly different between the two groups, among the three patients with DJK, two had LIV–SSV of −3, one had −1, and one had 0. No significant differences in other examinations were noted between the two groups.
Conclusions
Although more proximal LIV selection might lead to stable DA and DJK, the LIV selection should not be extended distally to prevent DA and DJK because favorable shoulder balance and clinical outcome can still be achieved.
3.Assessment of colorectal polyp detection along the short-axis direction of the intestinal lumen during colonoscopic observation: a retrospective study in Japan
Daichi MORI ; Atsushi KATAGIRI ; Yoshinao ONISHI ; Yuta YAMAZAKI ; Kensuke HIGUCHI ; Norihiro SUZUKI ; Kazuo KIKUCHI ; Shinya NAKATANI ; Takahisa FUJIWARA ; Kazuya INOKI ; Kenichi KONDA ; Masayuki TOJO ; Fuyuhiko YAMAMURA ; Hitoshi YOSHIDA
Clinical Endoscopy 2026;59(1):96-105
Background/Aims:
Colorectal polyp detection during colonoscopy is influenced by the lesion location, size, morphology, and histology. However, no studies have systematically assessed the difficulty of detection along the short axis of the intestinal lumen. This study aimed to evaluate the colorectal polyp detection rates on this axis during colonoscopy.
Methods:
This retrospective study analyzed 1,169 polyps in 513 patients who underwent colonoscopy at Showa University Hospital between November 2022 and February 2023. The short-axis lumen was divided into: upper right, lower right, lower left, and upper left. Each polyp detected was assigned to a quadrant. Detection rates were compared across quadrants and analyzed for associations with clinicopathological factors including lesion size, location, macroscopic type, and examiner experience.
Results:
The lesion detection rates varied significantly by quadrant. The upper left quadrant had the lowest detection rate (17.5%) compared with the expected 25.0% per quadrant. Subgroup analyses consistently confirmed the lower detection rates in this quadrant across most lesion types and patient groups, except for lesions in the cecum and rectum.
Conclusions
The lower detection rate in the upper left quadrant suggests that this orientation poses a challenge and may increase the number of missed lesions. Enhanced examination of this area may improve detection; however, further prospective studies are required.
4.Patient-specific mechanical analysis of pedicle screw insertion in simulated osteoporotic spinal bone models derived from medical images
Norihiro NISHIDA ; Hidenori SUZUKI ; Hanvey TETSU ; Yuki MORISHITA ; Yogesh KUMARAN ; Fei JIANG ; Masahiro FUNABA ; Kazuhiro FUJIMOTO ; Yusuke ICHIHARA ; Takashi SAKAI ; Junji OHGI
Asian Spine Journal 2024;18(5):621-629
Methods:
Male and female patients with computed tomography data were selected. Dimensions of the first thoracic (T1), fourth lumbar (L4), and fifth lumbar (L5) vertebrae were measured, and bone models consisting of the cancellous and cortical bones made from polyurethane foam were created. PS with diameters of 4.5 mm, 5.5 mm, and 6.5 mm were used. T1 PS were 25 mm long, and L4 and L5 PS were 40 mm long. The bone models were secured with cement, and the MIT was measured using a calibrated torque wrench. After MIT testing, the PS head was attached to the machine’s crosshead. POS was then calculated at a crosshead speed of 5 mm/min until failure.
Results:
The L4 and L5 were notably larger in female bone models, whereas the T1 vertebra was larger in male bone models. Consequently, the MIT and POS for L4 and L5 were higher in female bone models across all PS diameters than in male bone models. Conversely, the MIT for T1 was higher in male bone models across all PS; however, no significant differences were observed in the POS values for T1 between sexes.
Conclusions
The mechanical properties of the proposed bone models can vary based on the vertebral structure and size. For accurate 3D surgical and mechanical simulations in the creation of custom-made medical devices, bone models must be constructed from patientspecific medical images.
5.C5 Palsy of Patients with Proximal-Type Cervical Spondylotic Amyotrophy
Yasuaki IMAJO ; Norihiro NISHIDA ; Masahiro FUNABA ; Yuji NAGAO ; Hidenori SUZUKI ; Takashi SAKAI
Asian Spine Journal 2022;16(5):723-731
Methods:
Sixty patients with PCSA who underwent surgical treatment of the cervical spine were enrolled. The radiological findings on plain radiographs, computed tomography (CT), and magnetic resonance imaging (MRI) were evaluated. The cervical lordotic angles, C2–C7 sagittal vertical axis (SVA), and T1 slope were assessed on a lateral radiograph in the neutral position. CT was used to assess the width of the intervertebral foramen and the anterior protrusion of the superior articular process on the axial view. MRI was used to determine the number of levels of compression (NLC) and the presence of a high-intensity area in the spinal cord in the T2- weighted midsagittal view. The preoperative and postoperative strengths of the most atrophic muscles were evaluated using manual muscle testing. Improvements in strength were classified as excellent (five grades recovered), good (more than one grade recovered), fair (no improvement), or poor (worsened).
Results:
The prevalence of C5 palsy was 17% (10/60). Patients with poor outcomes had higher NLC and Δ C2–C7 SVA than patients with excellent, good, and fair outcomes (p =0.015; odds ratio [OR], 5.758; 95% confidence interval [CI], 1.397−23.726 for a change of 10% and p =0.048; OR, 1.068; 95% CI, 0.992−1.141 for a change of 10%, respectively).
Conclusions
ΔC2–C7 SVA and NLC may be used as prognostic factors for achieving a poor outcome following surgery in patients with PCSA. More focus is needed on preventing the increase in ΔC2–C7 SVA.
6.Frequency and clinical features of deficient mismatch repair in ovarian clear cell and endometrioid carcinoma
Tamaki TANAKA ; Kazuhiro TAKEHARA ; Natsumi YAMASHITA ; Mika OKAZAWA-SAKAI ; Kazuya KURAOKA ; Norihiro TERAMOTO ; Kenichi TAGUCHI ; Katsushige YAMASHIRO ; Hidenori KATO ; Tomoya MIZUNOE ; Rie SUZUKI ; Dan YAMAMOTO ; Arisa UEKI ; Toshiaki SAITO
Journal of Gynecologic Oncology 2022;33(5):e67-
Objective:
To clarify the frequency of deficient mismatch repair (dMMR) in Japanese ovarian cancer patients, we examined microsatellite instability (MSI) status and immunohistochemistry (IHC) subtypes, including endometrioid carcinoma (EMC), clear cell carcinoma (CCC), or a mixture of both (Mix).
Methods:
We registered 390 patients who were diagnosed with EMC/CCC/Mix between 2006 and 2015 and treated at seven participating facilities. For 339 patients confirmed eligible by the Central Pathological Review Board, MSI, IHC, and MutL homolog 1 methylation analyses were conducted. The tissues of patients with Lynch syndrome (LS)-related cancer histories, such as colorectal and endometrial cancer, were also investigated.
Results:
MSI-high (MSI-H) status was observed in 2/217 CCC (0.9%), 10/115 EMC (8.7%), and 1/4 Mix (25%). Additionally, loss of MMR protein expression (LoE-MMR) was observed in 5/219 (2.3%), 16/115 (14.0%), and 1/4 (25%) patients with CCC, EMC, and Mix, respectively. Both MSI-H and LoE-MMR were found significantly more often in EMC (p<0.001). The median (range) ages of patients with MMR expression and LoE-MMR were 54 (30–90) and 46 (22–76) (p=0.002), respectively. In the multivariate analysis, advanced stage and histological type were identified as prognostic factors.
Conclusion
The dMMR rate for EMC/CCC was similar to that reported in Western countries. In Japan, it is assumed that the dMMR frequency is higher because of the increased proportion of CCC.
7.Assessment of environmental sustainability in renal healthcare
Kei NAGAI ; Hiroaki SUZUKI ; Atsushi UEDA ; John W. M. Agar ; Norihiro ITSUBO
Journal of Rural Medicine 2021;16(3):132-138
The health effects of climate change are becoming increasingly important; there are direct effects from heatwaves and floods, and indirect effects from the altered distribution of infectious diseases and changes in crop yield. Ironically, the healthcare system itself carries an environmental burden, contributing to environmental health impacts. Life cycle assessment is a widely accepted and well-established method that quantitatively evaluates environmental impact. Given that monetary evaluations have the potential to motivate private companies and societies to reduce greenhouse gas emissions using market mechanisms, instead of assessing the carbon footprint alone, we previously developed a life cycle impact assessment method based on an endpoint that integrates comprehensive environmental burdens into a single index—the monetary cost. Previous investigations estimated that therapy for chronic kidney disease had a significant carbon footprint in the healthcare sector. We have been aiming to investigate on the environmental impact of chronic kidney disease based on field surveys from the renal department in a hospital and several health clinics in Japan. To live sustainably, it is necessary to establish cultures, practices, and research that aims to conserve resources to provide environmentally friendly healthcare in Japan.
8.A Case in Which Inhaled Nitric Oxide Was Effective for Managing Pulmonary Hypertension after Mitral Valve Replacement
Ryosuke KOWATARI ; Yasuyuki SUZUKI ; Masahito MINAKAWA ; Norihiro KONDO ; Kengo TANI ; Ikuo FUKUDA
Japanese Journal of Cardiovascular Surgery 2018;47(1):22-25
Pulmonary hypertension persisted in a 57-year-old man after mitral and tricuspid valve replacement to treat mitral and tricuspid regurgitation. Heart failure gradually worsened after surgery. Pulmonary hypertension was initially considered as the major reason for the heart failure, and inhaled nitric oxide was administered. Thereafter, the heart failure improved and mechanical circulatory assist could have been avoided. We believe that inhaled nitric oxide is a less invasive and effective method for improving pulmonary hypertension and hemodynamics after mitral valve replacement.
9.Diagnostic accuracy of neuropsychological tests for classification of dementia
Takuya Yagi ; Daisuke Ito ; Daisuke Sugiyama ; Satoko Iwasawa ; Hajime Tabuchi ; Mika Konishi ; Machiko Araki ; Naho Saitoh ; Yoshihiro Nihei ; Masaru Mimura ; Norihiro Suzuki
Neurology Asia 2016;21(1):47-54
Although numerous studies have shown that each neuropsychological test is effective for diagnosing
mild cognitive impairment (MCI) or Alzheimer’s disease (AD), studies comparing diagnostic accuracies
of various neuropsychological tests are relatively rare and practical cutoff values are not available. The
present study aimed to investigate the validity of neuropsychological tests and develop cutoff values
for each in differentiating healthy control (HC), MCI and AD groups. A total of 84 HC, 187 with
MCI and 195 with AD were evaluated by the selected seven neuropsychological tests using receiver
operating characteristic (ROC) curve analysis. Logical Memory (LM) delayed recall (cutoff, 7) and
Rey Auditory Verbal Learning Test (RAVLT) delayed recall (cutoff, 6) were effective for differentiating
HC from MCI. To distinguish MCI and AD, Rey Osterrieth Complex Figure Test (ROCFT) 3 mindelayed
recall (cutoff, 6) and LM immediate recall (cutoff, 4) were excellent. Delayed recall of verbal
materials, as indexed by LM and RAVLT was sensitive for discriminating MCI from HC. Handling
visual memory traces, as indexed by ROCFT and immediate verbal information by LM were sensitive
for differentiating MCI and AD.
Alzheimer Disease
;
Dementia
;
Neuropsychological Tests
10.The Efficacy of Conventional Aortic Valve Replacement for Severe Aortic Valve Stenosis Divided by Risk Classification Using the Japanese Scoring System
Kazuyuki Daitoku ; Kaoru Hattori ; Wakako Fukuda ; Norihiro Kondo ; Satoshi Taniguchi ; Masahito Minakawa ; Kozo Fukui ; Yasuyuki Suzuki ; Ikuo Fukuda ; Hiroyuki Itaya
Japanese Journal of Cardiovascular Surgery 2014;43(2):43-48
Objective : Transarterial or transapical aortic valve replacement (TAVR) procedures have been performed for high-risk patients with severe aortic valve stenosis (AS) in western countries. A high-risk patient is defined as having an STS score greater than 10%. In Japan, aortic valve replacement (AVR) with cardiopulmonary bypass (CPB) is standard care for AS, even if the patient is at high risk of developing complications. We calculated an expected operative risk of patients using a JAPAN score established by Japanese Adult Cardiovascular Surgery Database (JACVSD). Patients and Methods : Patients were divided into three groups : score less than 5%, low risk (LR) ; score 5-10%, moderate risk (MR) ; score more than 10%, high risk (HR). We also evaluated the efficacy of conventional AVR in each group. Between January 2002 and May 2011, we performed conventional AVR in our hospital and 116 patients who underwent AVR for symptomatic AS were enrolled in this study. Results : There were 79 patients in the LR group, 30 patients in the MR group and 7 patients in the HR group. The mean score was 2.6±1.1% in the LR group, 6.8±1.4% in the MR group and 23.3±16.8% in the HR group respectively. The mean follow-up period was 7.6±0.3 years. Preoperative co-morbidity was not statistically significant among three groups, however more octogenarians were found in the HR group. The aortic valve area and left ventricular ejection fraction (LVEF) were significantly smaller in the HR group. There were 4 cancer patients. The HR group had significantly longer operation and CPB times than the LR group. The operative mortality in all cases was 1.6%. Overall survival at 5 years was 78%. Actual survival at 5 years was 77% in the LR group, 82% in the MR group and 71% in the HR group. The major adverse cardiac and cerebrovascular event (MACCE)-free ratio at 5 years was 85%. Absence of death caused by MACCE at 5 years was 93%. All cancer patients died after AVR due to advancement in cancer. Conclusion : The results of conventional AVR with CPB were satisfactory in each group. Cancer patients may be good candidates for TAVR in the future.


Result Analysis
Print
Save
E-mail