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Spine | 2001

Long-term results of double-door laminoplasty for cervical stenotic myelopathy.

Atsushi Seichi; Katsushi Takeshita; Isao Ohishi; Hiroshi Kawaguchi; Toru Akune; Yorito Anamizu; Tomoaki Kitagawa; Kozo Nakamura

Study Design. A retrospective study of the long-term results from double-door laminoplasty (Kurokawa’s method) for patients with myelopathy caused by ossification of the posterior longitudinal ligament and cervical spondylosis was performed. Objective. To know whether the short-term results from double-door laminoplasty were maintained over a 10-year period and, if not, the cause of late deterioration. Summary of Background Data. There are few long-term follow-up studies on the outcome of laminoplasty for cervical stenotic myelopathy. Methods. In this study, 35 patients with cervical myelopathy caused by ossification of the posterior longitudinal ligament in the cervical spine and 25 patients with cervical spondylotic myelopathy, including 5 patients with athetoid cerebral palsy, underwent double-door laminoplasty from 1980 through 1988 and were followed over the next 10 years. The average follow-up period was 153 months (range, 120–200 months) in patients with ossification of the posterior longitudinal ligament and 156 months (range, 121–218 months) in patients with cervical spondylotic myelopathy. Neurologic deficits before and after surgery were assessed using a scoring system proposed by the Japanese Orthopedic Association (JOA score). Patients who showed late deterioration received further examination including computed tomography scan and magnetic resonance imaging of the cervical spine. Results. In 32 of the patients with ossification of the posterior longitudinal ligament and 23 of the patients with cervical spondylotic myelopathy, myelopathy improved after surgery. The improvement of Japanese Orthopedic Association scores was maintained up to the final follow-up assessment in 26 of the patients with ossification of the posterior longitudinal ligament and 21 of the patients with cervical spondylotic myelopathy. Late neurologic deterioration occurred in 10 of the patients with ossification of the posterior longitudinal ligament an average of 8 years after surgery, and in 4 of the patients with cervical spondylotic myelopathy, including the 3 patients with athetoid cerebral palsy, an average of 11 years after surgery. The main causes of deterioration in patients with ossification of the posterior longitudinal ligament were a minor trauma in patients with residual cervical cord compression caused by ossification of the posterior longitudinal ligament and thoracic myelopathy resulting from ossification of the yellow ligament in the thoracic spine. Conclusions. The short-term results of laminoplasty for cervical stenotic myelopathy were maintained over 10years in 78% of the patients with ossification of the posterior longitudinal ligament, and in most of the patients with cervical spondylotic myelopathy, except those with athetoid cerebral palsy. Double-door laminoplasty is a reliable procedure for individuals with cervical stenotic myelopathy.


Journal of Orthopaedic Science | 2009

JOA Back Pain Evaluation Questionnaire (JOABPEQ)/JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) The report on the development of revised versions April 16, 2007

Mitsuru Fukui; Kazuhiro Chiba; Mamoru Kawakami; Shinichi Kikuchi; Shin-ichi Konno; Masabumi Miyamoto; Atsushi Seichi; Tadashi Shimamura; Osamu Shirado; Toshihiko Taguchi; Kazuhisa Takahashi; Katsushi Takeshita; Toshikazu Tani; Yoshiaki Toyama; Kazuo Yonenobu; Eiji Wada; Takashi Tanaka; Yoshio Hirota

1 Laboratory of Statistics, Osaka City University Faculty of Medicine, Osaka, Japan 2 Department of Orthopaedic Surgery, Keio University, 35 Shinanomachi, Shinjuku, Tokyo 160-8582, Japan 3 Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan 4 Department of Orthopaedic Surgery, School of Medicine, Fukushima Medical University, Fukushima, Japan 5 Department of Orthopedic Surgery, Nippon Medical School, Tokyo, Japan 6 Department of Orthopaedic Surgery, The University of Tokyo, Tokyo, Japan 7 Department of Orthopaedic Surgery, Iwate Medical University School of Medicine, Morioka, Japan 8 Department of Orthopaedic Surgery, Saitama Medical School. Saitama, Japan 9 Department of Orthopedic Surgery, Yamaguchi University School of Medicine, Yamaguchi, Japan 10 Department of Orthopedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan 11 Department of Orthopaedics, Kochi Medical School, Kochi, Japan 12 Department of Orthopaedic Surgery, Hoshigaoka Koseinenkin Hospital, Osaka, Japan 13 National Hospital Organization, Osaka-Minami Medical Center, Osaka, Japan 14 Department of Internal Medicine, Houai Hospital, Osaka, Japan 15 Department of Public Health, Osaka City University Faculty of Medicine, Osaka, Japan


Spine | 2008

Surgical results and related factors for ossification of posterior longitudinal ligament of the thoracic spine: A multi-institutional retrospective study

Morio Matsumoto; Kazuhiro Chiba; Yoshiaki Toyama; Katsushi Takeshita; Atsushi Seichi; Kozo Nakamura; Jun Arimizu; Shunsuke Fujibayashi; Shigeru Hirabayashi; Toru Hirano; Motoki Iwasaki; Kouji Kaneoka; Yoshiharu Kawaguchi; Kosei Ijiri; Takeshi Maeda; Yukihiro Matsuyama; Yasuo Mikami; Hideki Murakami; Hideki Nagashima; Kensei Nagata; Shinnosuke Nakahara; Yutaka Nohara; Shiro Oka; Keizo Sakamoto; Yasuo Saruhashi; Yutaka Sasao; Katsuji Shimizu; Toshihiko Taguchi; Makoto Takahashi; Yasuhisa Tanaka

Study Design. Retrospective multi-institutional study Objective. To describe the surgical outcomes in patients with ossification of the posterior longitudinal ligament in the thoracic spine (T-OPLL) and to clarify factors related to the surgical outcomes. Summary of Background Data. Detailed analyses of surgical outcomes of T-OPLL have been difficult because of the rarity of this disease. Methods. The subjects were 154 patients with T-OPLL who were surgically treated at 34 institutions between 1998 and 2002. The surgical procedures were laminectomy in 36, laminoplasty in 51, anterior decompression via anterior approach in 25 and via posterior approach in 29, combined anterior and posterior fusion in 8, and sternum splitting approach in 5 patients. Instrumentation was conducted in 52 patients. Assessments were made on (1) The Japanese Orthopedic Association (JOA) scores (full score, 11 points), its recovery rates, (2) factors related to surgical results, and (3) complications and their consequences. Results. (1) The mean JOA score before surgery was 4.6 ± 2.0 and, 7.1 ± 2.5 after surgery. The mean recovery rate was 36.8% ± 47.4%. (2) The recovery rate was 50% or higher in 72 patients (46.8%). Factors significantly related to this were location of the maximum ossification (T1–T4) (odds ratio, 2.43–4.17) and the use of instrumentation (odds ratio, 3.37). (3) The frequent complications were deterioration of myelopathy immediately after surgery in 18 (11.7%) and dural injury in 34 (22.1%) patients. Conclusion. The factors significantly associated with favorable surgical results were maximum ossification located at the upper thoracic spine and use of instrumentation. T-OPLL at the nonkyphotic upper thoracic spine can be treated by laminoplasty that is relatively a safe surgical procedure for neural elements. The use of instrumentation allows correction of kyphosis or prevention of progression of kyphosis, thereby, enhancing and maintaining decompression effect, and its use should be considered with posterior decompression.


Journal of Bone and Joint Surgery, American Volume | 2001

Insulin Secretory Response Is Positively Associated with the Extent of Ossification of the Posterior Longitudinal Ligament of the Spine

Toru Akune; Naoshi Ogata; Atsushi Seichi; Isao Ohnishi; Kozo Nakamura; Hiroshi Kawaguchi

Background: Glucose intolerance is frequently found in patients with ossification of the posterior longitudinal ligament of the spine. This study was undertaken to examine the relationship between glucose intolerance and the extent of ossification in patients with ossification of the posterior longitudinal ligament. Methods: A total of 100 patients with ossification of the posterior longitudinal ligament (the overall study group), including fifty-two inpatients who were scheduled to have an operation (the inpatient group) and forty-eight outpatients who had undergone an operation, were analyzed. Indices of glucose metabolism—fasting plasma glucose and serum insulin levels, hemoglobin A1c level, and insulinogenic index (a ratio of the increment of the serum level of insulin to that of glucose)—as well as age and body-mass index were correlated with the extent of ossification, as determined by the number of vertebral levels affected with ossification of the posterior longitudinal ligament (extent of ossification), in the inpatient group. In addition, a similar analysis was performed in twenty-eight inpatients (the selected inpatient group) whose ages and body-mass indices were within one standard deviation of the mean values of those of the inpatient group. Association of a polymorphism in the gene of insulin receptor substrate-1, an essential substrate in insulin signaling, with the extent of ossification was evaluated with genomic DNA extracted from the overall study group. Results: Multiple-regression analysis revealed direct correlations of age (p = 0.038), body-mass index (p = 0.006), and insulinogenic index (p = 0.0003) with the extent of ossification of the posterior longitudinal ligament in the inpatient group. The fasting plasma glucose level, the hemoglobin A1c level, and the stage of glucose tolerance were not associated with the extent of ossification. In the analysis of the selected inpatient group, only the insulinogenic index was correlated with the extent of ossification (p = 0.002). However, no significant association was seen between the insulin receptor substrate-1 polymorphism and the extent of ossification. Conclusions: The insulin secretory response was associated with the extent of ossification of the posterior longitudinal ligament. Since insulin receptor substrate-1 is expressed both in the spinal ligament and in the tissues regulating glucose metabolism, we speculate that some other molecules related to insulin signaling that are impaired only in the tissues regulating glucose metabolism may be responsible for the progression of ossification. We also speculate that the upregulation of insulin production due to the impairment of insulin action may stimulate osteoprogenitor cells in the ligament to induce ossification. Clinical Relevance: The insulinogenic index may be useful as a serum marker for the prediction of progression of ossification of the posterior longitudinal ligament. This study may serve as a stimulus for evaluation of the use of various drugs that may improve the response to insulin in the tissues regulating glucose metabolism to prevent the progression of ossification.


Spine | 2008

Radiographic predictors for the development of myelopathy in patients with ossification of the posterior longitudinal ligament: a multicenter cohort study.

Shunji Matsunaga; Kozo Nakamura; Atsushi Seichi; Toru Yokoyama; Satoshi Toh; Shoichi Ichimura; Kazuhiko Satomi; Kenji Endo; Kengo Yamamoto; Yoshiharu Kato; Tatsuo Ito; Yasuaki Tokuhashi; Kenzo Uchida; Hisatoshi Baba; Norio Kawahara; Katsuro Tomita; Yukihiro Matsuyama; Naoki Ishiguro; Motoki Iwasaki; Hideki Yoshikawa; Kazuo Yonenobu; Mamoru Kawakami; Munehito Yoshida; Shinsuke Inoue; Toshikazu Tani; Kazuo Kaneko; Toshihiko Taguchi; Takanori Imakiire; Setsuro Komiya

Study Design. A multicenter cohort study was performed retrospectively. Objective. To identify radiographic predictors for the development of myelopathy in patients with ossification of the posterior longitudinal ligaments (OPLL). Summary of Background Data. The pathomechanism of myelopathy in the OPLL remains unknown. Some patients with large OPLL have not exhibited myelopathy for a long periods of time. Predicting the course of future neurologic deterioration in asyptomatic patients with OPLL is difficult at their initial visit. Methods. A total of 156 OPLL patients from 16 spine institutes with an average of 10.3 years of follow-up were reviewed. Subjects underwent a plain roentgenogram, computed tomography (CT), and magnetic resonance imaging of the cervical spine during the follow-up. The trauma history of the cervical spine, maximum percentage of spinal canal stenosis in a plain roentgenogram and CT, range of motion of the cervical spine, and axial ossified pattern in magnetic resonance imaging or CT were reviewed in relation to the existence of myelopathy. Results. All 39 patients with greater than 60% spinal canal stenosis on the plain roentgenogram exhibited myelopathy. Of 117 patients with less than 60% spinal canal stenosis, 57 (49%) patients exhibited myelopathy. The range of motion of the cervical spine was significantly larger in patients with myelopathy than in those of without it. The axial ossified pattern could be classified into 2 types: a central type and a lateral deviated type. The incidence of myelopathy in patients with less than 60% spinal canal stenosis was significantly higher in the lateral deviated-type group than in the central-type group. Fifteen patients of 156 subjects developed trauma-induced myelopathy. Of the 15 patients, 13 had mixed-type OPLL and 2 had segmental-type OPLL. Conclusion. Static and dynamic factors were related to the development of myelopathy in OPLL.


Journal of Bone and Mineral Research | 2002

Nucleotide Pyrophosphatase Gene Polymorphism Associated With Ossification of the Posterior Longitudinal Ligament of the Spine

Yu Koshizuka; Hiroshi Kawaguchi; Naoshi Ogata; Toshiyuki Ikeda; Akihiko Mabuchi; Atsushi Seichi; Yusuke Nakamura; Kozo Nakamura; Shiro Ikegawa

Ossification of the posterior longitudinal ligament (OPLL) of the spine is a disease that causes paralysis by compressing the spinal cord. Based on the fact that the nucleotide pyrophosphatase (Npps) gene is responsible for ectopic ossification in ttw, an OPLL model mouse, the possibility was explored whether the human NPPS gene is associated with susceptibility to and severity of OPLL. First, we screened for single‐nucleotide polymorphisms (SNPs) in the human NPPS locus using selected 25 OPLL patients with young onset (<35 years old) or severe ossification (>10 ossified vertebrae), and identified three novel SNPs in the locus. A case‐control association study between 180 OPLL patients and 265 non‐OPLL controls showed that one of these SNPs, IVS15‐14T → C substitution, was more frequently observed in OPLL patients (p = 0.022), especially in those with severe ossification (p < 0.0001) and young onset (p = 0.002), than in controls. A stratified study with the number of ossified vertebrae in OPLL patients revealed that IVS15‐14T → C substitution (p = 0.013) as well as young onset (p = 0.046) and female sex (p = 0.006) were associated with severe ossification. We conclude that the IVS15‐14T → C substitution in the human NPPS gene is associated not only with susceptibility to, but also with severity of OPLL.


Spine | 2004

Postoperative expansion of intramedullary high-intensity areas on T2-weighted magnetic resonance imaging after cervical laminoplasty.

Atsushi Seichi; Katsushi Takeshita; Hiroshi Kawaguchi; Susumu Nakajima; Toru Akune; Kozo Nakamura

Study Design. A cohort study. Objective. To determine the frequency of swelling of the spinal cord with an intramedullary lesion occurring after laminoplasty for nontraumatic cervical myelopathy and the possible mechanism of postoperative motor paresis of the upper extremity. Summary of Background Data. Postoperative enlargement of the spinal cord with an intramedullary lesion after decompression surgery for cervical stenotic myelopathy has been reported. But the frequency of the incidence remains unknown. Postoperative motor paresis occurring mainly in the C5 and C6 segments is known but various theories on its etiology exist, including the root involvement hypothesis and the spinal cord impairment hypothesis. Thus, the etiology is controversial. Methods. One hundred fourteen patients with cervical stenotic myelopathy were included in this study. All of them underwent preoperative magnetic resonance imaging and postoperative magnetic resonance imaging 3 weeks after surgery. We watched for the occurrence of postoperative neurologic deterioration including paralysis of the upper extremities. We also observed the presence or absence of postoperative abnormal expansion of T2 high-signal intensity areas on magnetic resonance imaging in the spinal cord. Results. Seven patients (6.1%) showed postoperative abnormal expansion of the T2 high-signal intensity area; 3 of the 7 were asymptomatic. A total of 9 patients (7.9%) experienced unilateral upper motor paresis after surgery. In 4 of the 9 cases, paresis of the unilateral deltoid, biceps and brachialis muscles (proximal paresis) occurred between 4 and 6 days after surgery. None of the 4 showed postoperative abnormal expansion of the T2 high-signal intensity area. In 3 other of the 9 patients, distal paresis occurred just after surgical intervention. Two of the 3 showed postoperative abnormal expansion of the T2 high-signal intensity area and 1 showed slight expansion of the area. In the other 2 cases, diffuse paresis occurred, and their postoperative magnetic resonance imaging showed abnormal expansion of the T2 high-signal intensity area. Conclusions. Spinal cord enlargement with abnormal expansion of the T2 high-signal intensity area, although not common, is an unpreventable complication after laminoplasty. This was strongly related with distal and diffuse type of postoperative paresis of the upper extremity without deterioration of lower motor function, but was little associated with a proximal type of paresis, so-called C5 and C6 palsies.


Journal of Orthopaedic Science | 2008

Japanese Orthopaedic Association Back Pain Evaluation Questionnaire. Part 3. Validity study and establishment of the measurement scale

Mitsuru Fukui; Kazuhiro Chiba; Mamoru Kawakami; Shinichi Kikuchi; Shin-ichi Konno; Masabumi Miyamoto; Atsushi Seichi; Tadashi Shimamura; Osamu Shirado; Toshihiko Taguchi; Kazuhisa Takahashi; Katsushi Takeshita; Toshikazu Tani; Yoshiaki Toyama; Eiji Wada; Kazuo Yonenobu; Takashi Tanaka; Yoshio Hirota

BackgroundThe Japanese Orthopaedic Association decided to revise the JOA score for low back pain and to develop a new outcome measure. In February 2002, the first survey was performed with a preliminary questionnaire consisting of 60 evaluation items. Based on findings of that survey, 25 items were selected for a draft of the JOA Back Pain Evaluation Questionnaire (JOABPEQ). The second survey was performed to confirm the reliability of the draft questionnaire. This article further evaluates the validity of this questionnaire and establishes a measurement scale.MethodsThe subjects of this study consisted of 355 patients with low back disorders of any type (201 men, 154 women; mean age 50.7 years). Each patient was asked to fill in a self-administered questionnaire. Superficial validity was checked in terms of the completion rate for filling out the entire questionnaire. Factor analysis was then performed to evaluate the validity of the questionnaire and establish a measurement scale.ResultsAs a result of the factor analysis, 25 items were categorized into five factors. The factors were named based on the commonality of the items: social function, mental health, lumbar function, walking ability, and low back pain. To establish a measurement scale for each factor, we determined the coefficient for each item so the difference between the maximum factor scores and minimum factor scores was approximately 100. We adjusted the formula so the maximum for each factor score was 100 and the minimum was 0.ConclusionsWe confirmed the validity of the JOA Back Pain Evaluation Questionnaire and est ablished a measurement scale.


Journal of Orthopaedic Science | 2007

JOA Back Pain Evaluation Questionnaire: initial report

Mitsuru Fukui; Kazuhiro Chiba; Mamoru Kawakami; Shinichi Kikuchi; Shin-ichi Konno; Masabumi Miyamoto; Atsushi Seichi; Tadashi Shimamura; Osamu Shirado; Toshihiko Taguchi; Kazuhisa Takahashi; Katsushi Takeshita; Toshikazu Tani; Yoshiaki Toyama; Eiji Wada; Kazuo Yonenobu; Takashi Tanaka; Yoshio Hirota

BackgroundThere is no widely accepted objective evaluation for lumbar spine disorders. New outcome measures should be patient-oriented and should measure symptoms and self-reported functional status in multiple dimensions. The aim of this study was to identify items to be included in the disease-specific quality of life (QOL) questionnaire for the assessments of patients with lumbar spine disorders.MethodsThe draft of the QOL questionnaire that consisted of a total of 60 items, including 24 items derived from the Japanese version of the Roland Morris Disability Questionnaire (RDQ) and 36 items derived from the Japanese version of Short Form 36 (SF-36), were administered to patients and controls. After obtaining written informed consent, the following data were collected from the patient group (n = 328) and the control group (n = 213): (1) background characteristics, including age, diagnosis, Japanese Orthopaedic Association (JOA) score, and finger to floor distance; (2) responses to the questionnaire; (3) the identification rate by discrimination analysis to select the candidates for adoption and by adopting explanatory variables. The items to be excluded were determined by examining the explanatory variables, which were selected after the discrimination analysis, by setting the candidate to-be-excluded items as an objective variable.ResultsBased on the distribution of the responses, two items, RDQ-15 and RDQ-19, were excluded. From the results of the correlation coefficient calculation for each question in the patient group, 33 items were excluded and 27 candidate items were adopted. Based on the adoption explanatory variable used in the discrimination analysis, 25 of the 27 candidate items for adoption were accepted.ConclusionsThis study identified the 25 specific questionnaire items that should be included in the questionnaire to evaluate QOL of patients with various lumbar spine disorders.


Spine | 2006

Prognostic Factors for Patients With Spinal Metastases From Lung Cancer

Satoshi Ogihara; Atsushi Seichi; Takahiro Hozumi; Hiroyuki Oka; Ryuuji Ieki; Kozo Nakamura; Taiji Kondoh

Study Design. We conducted a retrospective study to identify prognostic factors of patients with spinal metastases from lung cancer. Objective. To provide clinical data with strong association to the prognosis and to propose criteria determining indication of operation for spinal metastases. Summary of Background Data. To make a proper selection of patients for whom surgery is indicated, forecasting short-time survival after spinal metastases is very important. In the past, there has been no report of prognostic factors of patients with such metastases from this cancer. Methods. This study included 114 patients with spinal metastases of lung cancer. Tumors were histologically categorized as non-small cell lung cancer (NSCLC) in 94 patients and small cell lung cancer (SCLC) in 20 patients. We investigated prognostic factors after spinal metastases using Cox comparative hazard model and a preoperative prognostic score proposed by Tokuhashi. We also investigated the patients who underwent operation for spinal metastases from lung cancer in our hospital. Results. Multivariate analysis showed that the significant prognostic factors for survival after spinal metastases from NSCLC were performance status (PS), Ca, Alb. Among SCLC patients, Ca, Alb, and a history of chemotherapy were significant (P < 0.05) in univariate analysis. The score of Tokuhashi was not correlative to the survival period. Among the operated patients, postoperative PS was significant for the period of postoperative survival. Conclusion. PS, Ca, and Alb in NSCLC and Ca, Alb, and a history of chemotherapy in SCLC are useful for determining an indication of operation for spinal metastases from lung cancer.

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Atsushi Kimura

Jichi Medical University

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Yuichi Hoshino

Jichi Medical University

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Hirokazu Inoue

Jichi Medical University

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