Limestone Related Problems for Foundations in Central Vietnam

( Tomohiro Yasuda ) 대한지질공학회 2019 대한지질공학회 학술발표회논문집 Vol.2019 No.2

We conducted geological reconnaissance and exploratory drilling for a candidate plant site in Central Vietnam. The geological investigation reveals that the site is underlain by limestone. We identified typical limestone features, namely cavity, sinkhole, slump zone and Karst topography. It is concerned that foundation pressure may overstress cavities and cause collapse of cavities. That would result in new sinkhole or ground settlement, which may damage surrounding structures and buildings. Slump zones were observed below very stiff/dense overlying soils and immediately above limestone, where soils were very loose with SPT N-values of 5 or less. It is possible that slump zone expands by flowing loose soils into underlying cavities. The spread slump zone may cause sinkholes. Karst topography with depths varying from 40 to 70 metres is likely to cause several problems for pile foundation. Where piles are driven to the top of limestone, the pile lengths drastically vary in a short distance. When the piles are driven onto steeply inclined limestone surface and deep ditches, the piles can be damaged. Additionally, if the pile is supported on an overhang, its bearing capacity might be insufficient. To overcome limestone related problems, cavity probing and grout treatment for cavity and slump zone are required for proposed shallow and pile foundations. However, the probing and treatment are costly and time consuming. As the thorough probing and treatment are practically impossible, unexpected sinkhole or settlement remains unavoidable even after the probing and treatment. Consequently, we recommended relocating the site to avoid the limestone area.

Association between Pelvic Parameters and Vaginal Delivery

Yamada Tomohiro,Yamato Yu,Hasegawa Tomohiko,Yoshida Go,Yasuda Tatsuya,Banno Tomohiro,Arima Hideyuki,Oe Shin,Mihara Yuki,Ushirozako Hiroki,Ide Koichiro,Watanabe Yuh,Hosino Hironobu,Matsuyama Yukihiro 대한척추외과학회 2022 Asian Spine Journal Vol.16 No.2

Study Design: Cross-sectional study. Purpose: To investigate the association between vaginal delivery and pelvic parameters and clarify the effect of parity on parameter fluctuations. Overview of Literature: During vaginal delivery, the sacroiliac joint widens and the sacrum nutates (nods). However, the association between these pelvic parameters and parity is unknown. Methods: As part of a 2016 health screening, 320 female volunteers underwent whole-spine radiographs. Age-matched healthy women were grouped according to the number of vaginal deliveries (0, 1–2, or ≥3). Demographic variables and spinopelvic parameters were compared among the three groups. Results: Of the 320 volunteers, 213 were enrolled (mean age, 71.1±7.2 years). The mean number of vaginal deliveries was 2.2. The average pelvic incidence (PI) was 55.6°±11.1° and was significantly higher in the 90 women with three or more vaginal deliveries than in the other two groups (p<0.001). The average sacral slope was 33.4°±11.1° and was significantly higher in the women with three or more vaginal deliveries than in the 18 who did not deliver vaginally (p<0.001). The 105 women with one or two vaginal deliveries had significantly higher PIs and sacral slopes than did those who did not deliver vaginally (p<0.001). Conclusions: This is the first study documenting an association between vaginal delivery and pelvic parameters. Bony birth canal realignment during vaginal delivery can affect postnatal PI. Our study helps in understanding the PI changes over a woman’s life span.

Multi-Rod Constructs Can Increase the Incidence of Iliac Screw Loosening after Surgery for Adult Spinal Deformity

Tomohiro Banno,Tomohiko Hasegawa,Yu Yamato,Daisuke Togawa,Go Yoshida,Sho Kobayashi,Tatsuya Yasuda,Hideyuki Arima,Shin Oe,Yuki Mihara,Hiroki Ushirozako,Yukihiro Matsuyama 대한척추외과학회 2019 Asian Spine Journal Vol.13 No.3

Study Design: A retrospective study. Purpose: To investigate the incidence of iliac screw loosening with a two-rod vs. multi-rod construct and the effect on clinical and radiographic outcomes after surgery for adult spinal deformity (ASD). Overview of Literature: Multi-rod construct is useful for preventing rod fracture in ASD surgery. However, limited information is available regarding the incidence of iliac screw loosening after corrective fusion surgery using a multi-rod construct. Methods: Total 106 patients with ASD (24 men and 82 women; mean age, 68 years) who underwent corrective fusion surgery using bilateral iliac screws and were followed up for at least 1 year were reviewed. The following variables were compared between patients who underwent surgery with a two-rod and multi-rod construct: age, sex, bone mineral density (BMD), fusion level, high-grade osteotomy, L5/S interbody fusion, screw loosening (upper instrumented vertebra [UIV], S1, and iliac), rod fracture, proximal junctional kyphosis, spinopelvic parameters, and Oswestry Disability Index (ODI) score. We also compared patients with and without iliac screw loosening in the multi-rod construct group. Results: Of the 106 patients, 55 underwent surgery with a conventional two-rod construct and 51 with a multi-rod construct (three rods in 16, four rods in 35). Iliac and UIV screw loosening was observed in 24 patients (21%) and 35 patients (33%), respectively. The multi-rod group showed significantly higher incidence of iliac and UIV screw loosening and lower incidence of rod fracture. Patients with iliac screw loosening had a lower BMD than those without screw loosening; however, no significant differences were observed in the spinopelvic parameters or the ODI score. Conclusions: The use of multi-rod constructs led to a higher incidence of junctional screw loosening than the use of conventional two-rod constructs, especially in patients with osteoporosis. Iliac screw loosening did not affect sagittal alignment or clinical outcome in the short term.

Electro-Functional Octupolar π-Conjugated Columnar Liquid Crystals

Yasuda, Takuma,Shimizu, Tomohiro,Liu, Feng,Ungar, Goran,Kato, Takashi American Chemical Society 2011 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.133 No.34

<P>A series of propeller-shaped π-conjugated molecules based on 2,4,6-tris(thiophene-2-yl)-1,3,5-triazines has been designed and synthesized to obtain ambipolar charge-transporting liquid-crystalline materials. The 3-fold electron-donating aromatic units are attached to the electron-accepting triazine core, which forms electro-functional octupolar π-conjugated structures. These octupolar molecules self-organize into one-dimensional columnar nanostructures and exhibit ambipolar carrier transport behavior, which has been revealed by time-of-flight measurements. In this approach, electron-donor and acceptor electro-active segments are assembled individually in each column to give one-dimensional nanostructured materials with precisely tuned electronic properties. Their desirable electronic structures responsible for both hole and electron conductions have also been examined by cyclic voltammetry and theoretical calculations. The present results provide a new guideline and versatile approach to the design of ambipolar conductive nanostructured liquid-crystalline materials.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2011/jacsat.2011.133.issue-34/ja2035255/production/images/medium/ja-2011-035255_0014.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja2035255'>ACS Electronic Supporting Info</A></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja2035255'>ACS Electronic Supporting Info</A></P>

Relationship between Knee Osteoarthritis and Spinopelvic Sagittal Alignment in Volunteers over 50 Years of Age

Yasuda Tatsuya,Togawa Daisuke,Hasegawa Tomohiko,Yamato Yu,Kobayashi Sho,Yoshida Go,Banno Tomohiro,Arima Hideyuki,Oe Shin,Hoshino Hironobu,Koyama Hiroshi,Hanada Mitsuru,Imada Takayuki,Matsuyama Yukihir 대한척추외과학회 2020 Asian Spine Journal Vol.14 No.4

Study Design: Large cohort study of volunteers.Purpose: The purpose of this study was to investigate the relationship between the severity of knee osteoarthritis, assessed using the Kellgren-Lawrence (KL) grading scale, and spinopelvic sagittal alignment in older adult volunteers.Overview of Literature: The relationship between spinopelvic alignment in the sagittal plane and knee osteoarthritis in the coronal plane is unclear.Methods: Volunteers over 50 years of age underwent radiographic analysis. Radiographic parameters including pelvic tilt (PT), pelvic incidence (PI), lumbar lordosis (LL), thoracic kyphosis, and sagittal vertical axis (SVA) were measured. The the three Scoliosis Research Society-Schwab sagittal modifiers (PT, SVA, I–LL) were categorized and the KL grade was assessed. Differences in spinopelvic parameters and Oswestry Disability Index (ODI) scores among KL grades were evaluated.Results: A total of 396 volunteers (160 men, 236 women; mean age, 74.4 years) were analyzed. PI–LL and PT in KL4 were significantly higher compared to that in the other KL grades. However, there were no significant group differences in SVA. In women, but not in men, higher frequencies of the worst modifier grade (++) were observed for PI–LL and PT in the KL3 and KL4 groups compared to those for the other KL grades. In women, the ODI score in KL4 was worse compared to that in the other KL grades.Conclusions: Individuals over 50 years of age with severe knee osteoarthritis had poor lumbo-pelvic sagittal alignment. Moreover, the progression severity of knee osteoarthritis had more impact onstronger relationship with lumbo-pelvic malalignment and disability-related low back pain in women than in men.

Relationship between Spinal Hemangioblastoma Location and Age

Tatsuya Yasuda,Tomohiko Hasegawa,Yu Yamato,Sho Kobayashi,Daisuke Togawa,Tomohiro Banno,Hideyuki Arima,Shin Oe,Yukihiro Matsuyama 대한척추외과학회 2016 Asian Spine Journal Vol.10 No.2

Study Design: Retrospective case series. Purpose: To investigate the relationship between tumor location and clinical characteristics. Overview of Literature: Hemangioblastoma is a rare disease that develops in the central nervous system. Magnetic resonance imaging (MRI) is useful to evaluate hemangioblastomas. Hemangioblastoma’s location is designated as intramedullary, intramedullary+extramedullary, or extramedullary by MRI. Methods: We analyzed 11 patients who underwent surgery for spinal hemangioblastoma. Using T1 contrast axial MRI data, the cases were divided into three groups (intramedullary, intramedullary+extramedullary, and extramedullary). Patient demographics, MRI findings, and preoperative neurological status were analyzed and compared for each group. Results: The average age of patients with intramedullary, intramedullary+extramedullary, and extramedullary hemangioblastoma was 34.0, 64.4, and 67.5 years, respectively. Patients in the intramedullary hemangioblastoma group were younger than the other groups. Extramedullary cases had a smaller syrinx compared to the other groups. Conclusions: Age may play an important role in the hemangioblastoma tumor location and the subsequent diagnosis by an MRI.

Cardiac Rehabilitation Increases Exercise Capacity with a Reduction of Oxidative Stress

Taira Fukuda,Miwa Kurano,Kazuya Fukumura,Tomohiro Yasuda,Haruko Iida,Toshihiro Morita,Yumiko Yamamoto,Nami Takano,Issei Komuro,Toshiaki Nakajima 대한심장학회 2013 Korean Circulation Journal Vol.43 No.7

Background and Objectives: Reactive oxygen species (ROS) mediate various signaling pathways that underlie vascular inflammation in atherogenesis and cardiovascular diseases. Cardiac rehabilitation (CR) has a variety of multiple beneficial effects, including anti-inflam -matory effects. The purpose of the present study was to investigate the effects of CR on ROS in patients with cardiovascular diseases. Subjects and Methods: The serum level of derivatives of reactive oxidative metabolites, an index of oxidative stress, was measured in 100 patients with cardiovascular diseases before, and, subsequently, 3 and 6 months after, CR. A biological antioxidant potential (BAP) test was applied to assess the antioxidant power of the serum. Results: The resting reactive oxidative metabolite levels decreased 3-6 months after CR {pre: 351±97 Carratelli unit (CARR U), 3 months:329±77 CARR U, 6 months: 325±63 CARR U, all p<0.01} with the increase of the percentage of the predicted values of V˙O 2 peak and the percentage of the predicted values of V˙O 2 at the anaerobic threshold (V˙O 2 AT ) and the decrease of the B-type natriuretic peptide (BNP). The BAP test and antioxidative/oxidative stress ratio increased 6 months after CR. The % changes of the antioxidative/oxidative stress ratio was positively correlated with the % changes of V˙O 2 AT , and negatively correlated with the % changes of the BNP. Conclusion: These results suggest that intensive supervised CR significantly improved exercise capacity, which may be attributable to an adaptive response involving more efficient oxidative metabolites or the increased capacity of endogenous anti-oxidative systems in pa -tients with cardiovascular diseases.

Selective Angiography to Detect Anterior Spinal Artery Stenosis in Thoracic Ossification of the Posterior Longitudinal Ligament

Yoshida Go,Ushirozako Hiroki,Hasegawa Tomohiko,Yamato Yu,Yasuda Tatsuya,Banno Tomohiro,Arima Hideyuki,Oe Shin,Mihara Yuki,Yamada Tomohiro,Ide Koichiro,Watanabe Yuh,Ushio Takasuke,Matsuyama Yukihiro 대한척추외과학회 2022 Asian Spine Journal Vol.16 No.3

Study Design: Single-center prospective study.Purpose: To investigate anterior spinal artery (ASA) status using preoperative selective angiography in patients undergoing surgery for thoracic ossification of the posterior longitudinal ligament (T-OPLL).Overview of Literature: Surgery for T-OPLL has a high risk of neurological complications, which might be associated with insufficient spinal cord blood flow.Methods: This study prospectively examined nine T-OPLL patients who underwent posterior thoracic decompression with kyphosis correction and instrumented fusion at Hamamatsu University School of Medicine between 2017 and 2019. All underwent preoperative selective angiography to detect and evaluate the Adamkiewicz artery and ASA. Intraoperative neuromonitoring and Doppler ultrasonography were performed to analyze neurological complications and spinal cord blood flow.Results: All nine patients showed ASA stenosis in the area of T-OPLL. In all patients, the Adamkiewicz artery was located between T7 and L2 and the area of ASA stenosis corresponded to the level of T-OPLL and greatest spinal cord compression; intraoperative Doppler ultrasonography confirmed the ASA defect at the same spinal level. The number of spinal levels from the Adamkiewicz artery to the most compressive OPLL lesion was greater in the two patients who developed postoperative neurological deficit compared to those who did not (5.5 vs. 2.3, p=0.014).Conclusions: This is the first study to report detection of ASA stenosis in patients with T-OPLL. Maintaining spinal cord blood flow is important in these patients to avoid neurological deterioration.

Minimum Clinically Important Differences in Oswestry Disability Index Domains and Their Impact on Adult Spinal Deformity Surgery

Go Yoshida,Tomohiko Hasegawa,Yu Yamato,,Sho Kobayashi,Oe Shin,Tomohiro Banno,Yuuki Mihara,Hideyuki Arima,Hiroki Ushirozako,Tatsuya Yasuda,Daisuke Togawa,Yukihiro Matsuyama 대한척추외과학회 2019 Asian Spine Journal Vol.13 No.1

Study Design: Retrospective study. Purpose: To calculate the minimum clinically important difference (MCID) for total and individual domains of the Oswestry Disability Index (ODI) and assess score distribution and changes over time in surgically treated adult spinal deformity (ASD) patients. Overview of Literature: Despite the common use of ODI for assessing ASD, there are no robust studies defining MCID values for this index. Methods: This study included 240 consecutive ASD patients with a minimum of 2 years of follow-up. We calculated MCID values for total and individual ODI domains using all or part of the Scoliosis Research Society-22R questionnaire as anchors. Using current MCID values, we measured the acquisition rates in patients who acquired MCID at follow-up in both total and individual ODI domains. Differences in pathology, age, and locations of the upper and lower instrumented vertebrae were analyzed. Results: MCID of the total ODI score was 11%, with an area under the curve of 0.737. Each domain ranged from 0 to 2, with 1 being the most common value. In the pain and standing domains, >60% of the patients acquired MCID, although acquisition rates of the personal care, lifting, sleep, and sexual activity domains were relatively low (20%–35%). Patients with MCID had more radiographic improvement in lumbar lordosis, sagittal vertical axis, and T1 pelvic angle than those without MCID (p <0.05). Conclusions: To our knowledge, this is the first study to describe MCID of ODI (11%) after ASD surgery. In the pain and standing domains, most patients acquired MCID although the rates of acquisition of MCID in the personal care, lifting, sleep, and sexual activity domains were low. Spine surgeons should counsel their patients regarding the benefits and setbacks of ASD surgery.

Impact of Spinal Correction Surgeries with Osteotomy and Pelvic Fixation in Patients with Kyphosis Due to Osteoporotic Vertebral Fractures

Hasegawa Tomohiko,Ushirozako Hiroki,Yamato Yu,Yoshida Go,Yasuda Tatsuya,Banno Tomohiro,Arima Hideyuki,Oe Shin,Yamada Tomohiro,Ide Koichiro,Watanabe Yuh,Matsuyama Yukihiro 대한척추외과학회 2021 Asian Spine Journal Vol.15 No.4

Study DesignCombination of retrospective and prospective study.PurposeWe aimed to compare the clinical outcomes between local fixation surgery and spinopelvic fixation surgery for the treatment of kyphosis secondary to osteoporotic vertebral fractures with spinopelvic malalignment.Overview of LiteratureThe clinical characteristics of patients with rigid kyphosis due to osteoporotic vertebral fracture differ from that of middle-aged patients with vertebral fractures in terms of bone fragility and presence of spinopelvic malalignment. Little is known about the surgical strategies for these deformities, most especially the extent of fusion of vertebra involved.MethodsWe analyzed 24 patients with vertebral osteotomy at the level of the fracture and spinal fixation without pelvic fixation (local group), and 22 patients with vertebral osteotomy and pelvic fixation (pelvic group). Radiographic parameters, the incidence of proximal junctional kyphosis (PJK), distal junctional kyphosis (DJK), rod fractures, and the Oswestry Disability Index (ODI) were compared between the two groups over a 2-year follow-up period.ResultsIn the pelvic group, postoperative spinopelvic parameters significantly improved, with the improvements maintained. No remarkable changes in spinopelvic parameters were seen in the local group. The mean ODI scores 2 years after surgery were 45.3 and 33.0 in the local and pelvic group, respectively (p-value <0.05). There was no significant difference in the incidence of PJK in the local and pelvic groups, but there was a higher rate of DJK (41.7%) in the local group. In contrast, rod fractures were more common in the pelvic group (45.5%). Patients with DJK had higher ODI scores 2 years after surgery (52.0 in DJK patients vs. 34.8 in non-DJK patients; p-value <0.05).ConclusionsFor patients with rigid kyphosis due to osteoporotic vertebral fractures, better spinopelvic alignment and health-related quality of life can be achieved through extensive corrective surgery with pelvic fixation.