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Featured researches published by Yoichi Iizuka.


Journal of Neurosurgery | 2007

Cervical malalignment after laminoplasty : relationship to deep extensor musculature of the cervical spine and neurological outcome

Haku Iizuka; Takashi Nakajima; Yoichi Iizuka; Yasunori Sorimachi; Tsuyoshi Ara; Masahiro Nishinome; Kenji Takagishi

OBJECT The goal of this study was to investigate the relationship between preservation of the insertion of the deep extensor musculature of the cervical spine at C-2 and postoperative cervical alignment, especially differences between cases involving male and female patients, as well as the relationship between the loss of cervical lordosis and neurological outcome after laminoplasty. METHODS The authors reviewed the records of 50 patients who underwent laminoplasty to elevate the C-3 lamina with repair of the deep extensor musculature (Group A) and 31 patients who underwent laminoplasty by C-3 dome laminotomy or laminectomy (Group B). They compared the degree of cervical lordosis after laminoplasty with preoperative measurements. Neurological function at last follow-up was also compared with preoperative assessments. RESULTS In Group A, the mean values for pre- and postoperative cervical lordosis were 14.5 and 10.9 degrees, respectively (p > 0.18). In female patients, however, the pre- and postoperative means were 14.4 and 3.7 degrees, respectively (p < 0.004). In Group B, the overall means for pre- and postoperative cervical lordosis were 17.3 and 19.1 degrees, respectively (p > 0.48); the corresponding means for female patients were 15.0 and 14.1 degrees (p > 0.83). The mean percentages of neurological recovery were 54.1% in Group A and 54.8% in Group B. CONCLUSIONS Preservation of the insertion of the deep extensor musculature to the C-2 spinous process prevented significant changes in cervical alignment after laminoplasty, even among female patients. Neurological recovery was not affected by the loss of cervical lordosis.


Journal of Neurosurgery | 2009

Foot drop due to lumbar degenerative conditions: mechanism and prognostic factors in herniated nucleus pulposus and lumbar spinal stenosis

Yoichi Iizuka; Haku Iizuka; Satoshi Tsutsumi; Yumi Nakagawa; Takashi Nakajima; Yasunori Sorimachi; Tsuyoshi Ara; Masahiro Nishinome; Takayuki Seki; Kosuke Shida; Kenji Takagishi

OBJECT The aim of this study was to analyze the mechanism and prognostic factors of foot drop caused by lumbar degenerative conditions. METHODS The authors retrospectively reviewed the charts of 28 patients with foot drop due to a herniated nucleus pulposus (HNP) or lumbar spinal stenosis (LSS), scoring between 0 and 3 on manual muscle testing for the tibialis anterior muscles. They analyzed the mechanism of foot drop and whether the duration before the operation, preoperative tibialis anterior and extensor hallucis longus strength, age, gender, and diabetes mellitus were all found to be prognostic factors for postoperative tibialis anterior recovery. They also investigated whether the diagnosis had any influence on the prognosis. RESULTS The compression of double roots and a sequestrated fragment were observed, respectively, in 9 and 13 of 16 patients with HNP. Multiple levels including the L4-5 segment were decompressed in 8 of 12 patients with LSS. Analysis did not demonstrate any prognostic factor in surgically treated HNP, but significant associations with prognosis were observed with respect to preoperative tibialis anterior (p = 0.033) and extensor hallucis longus (p = 0.020) strength in patients with LSS. In addition, the postoperative muscle recovery in patients with HNP was significantly superior to that in patients with LSS (p = 0.011). CONCLUSIONS Double root compression was the most common condition associated with foot drop due to HNP. The diagnosis and preoperative tibialis anterior and extensor hallucis longus strength in LSS were factors that influenced recovery following an operation.


Journal of Orthopaedic Science | 2012

Characteristics of neck and shoulder pain (called katakori in Japanese) among members of the nursing staff

Yoichi Iizuka; Tetsuya Shinozaki; Tsutomu Kobayashi; Satoshi Tsutsumi; Toshihisa Osawa; Tsuyoshi Ara; Haku Iizuka; Kenji Takagishi

BackgroundThe characteristics of neck and shoulder pain (NSP), called katakori in Japanese, have not been well documented to date. The aim of this study was to clarify the characteristics of NSP through a questionnaire survey of members of the nursing staff.MethodsThe study population consisted of 484 nursing staff members of Gunma University Hospital in Japan. The questionnaire involved information on age, body mass index (BMI), gender, psychological stress at work, musculoskeletal pain at other anatomic sites (elbow/wrist, lumbar and knee), smoking history, and hypertension. If subjects had NSP, they were asked about any coexisting symptoms, the utilization of health services, and the precise location of NSP.ResultsThe total study population included 393 persons after 91 persons were excluded for various reasons. The point prevalence of NSP was 68.1% (268 of 393). Age, BMI, smoking history, and hypertension showed no significant trend for the prevalence of NSP in the univariate analyses. The occurrence of NSP was significantly higher in subjects with psychological stress, elbow/wrist pain, lumbar pain, and knee pain, respectively. A multivariate logistic regression analysis showed that gender, psychological stress, elbow/wrist pain, and lumbar pain were significantly associated with the occurrence of NSP. One hundred fifty-eight of those with NSP (58.9%) reported coexisting symptoms, and the most common was headache. Fifty-seven (21.2%) of the subjects with NSP had consulted medical or health practitioners, and bone setting was the most common service provider. The most common area of NSP was the superior part of the trapezius.ConclusionsThis study confirmed that NSP, katakori in Japanese, is a prevalent problem in a nursing staff, and several factors associated with NSP were identified.


European Spine Journal | 2009

Diagnosis of a previously unidentified primary site in patients with spinal metastasis: diagnostic usefulness of laboratory analysis, CT scanning and CT-guided biopsy

Yoichi Iizuka; Haku Iizuka; Satoshi Tsutsumi; Yumi Nakagawa; Takashi Nakajima; Yasunori Sorimachi; Tsuyoshi Ara; Masahiro Nishinome; Takayuki Seki; Kenji Takagishi

When the primary site is unknown in patients with spinal metastases, there can be problems in locating the site of tumor origin. Most previous reports on metastases of unknown origin have not been limited to the spine. The purpose of this study is to assess the usefulness of laboratory analysis, chest, abdominal and pelvic CT and CT-guided biopsy in patients with spinal metastases of unknown origin (SMUO). A retrospective review of the clinical histories of 27 patients with SMUO was done. A total of 43 patients with SMUO were seen at our institution between 2002 and 2007. Of the 43 patients, 27 who underwent all 3 tests (laboratory analysis including M protein and tumor markers, chest, abdominal and pelvic CT and CT-guided biopsy) were included in this study. We retrospectively assessed the diagnostic usefulness of those 3 tests in the 27 patients. In 27 patients, the final diagnosis was obtained in 26 patients. Myeloma was the most common malignancy followed by lung carcinoma. M protein was positive in all 7 patients with myeloma and negative in patients with other malignancies. The level of tumor markers was elevated in 16 of 17 patients with a solid tumor and in all 3 with lymphoma. CA15-3 was elevated in 4 of 27 patients, CA19-9 in 5 of 27 patients, CA125 in 2 of 27 patients, CEA in 6 of 27 patients, SCC in 2 of 27 patients, NSE in 7 of 27 patients, AFP in 1 of 27 patients, PIVKA-II in 1 of 27 patients, TPA in 6 of 27 patients, IAP in 3 of 12 patients, thyroglobulin in 2 of 27 patients, sIL-2R in 3 of 24 patients, and PSA in 5 of 17 male patients. Myeloma, lymphoma and prostate carcinoma had a marker with high sensitivity and specificity (M protein, sIL-2R and PSA). Eleven primary tumor sites (40.7%) were detected (6 lung, 1 prostate, 1 kidney, 1 thyroid, 1 liver, and 1 pancreas) by chest, abdominal and CT scanning. Biopsy led to determination of the final diagnosis in 12 (44.4%) of 27 patients (5 myelomas, 3 lymphomas, 2 prostate carcinomas, 1 renal-cell carcinoma, 1 thyroid carcinoma). In the remaining 15 patients, biopsy did not lead to determination of the final diagnosis, because the histological diagnosis was either an adenocarcinoma or an undifferentiated carcinoma, the tissue sample was not diagnostic. A laboratory analysis limited to specific tumor markers such as PSA and protein electrophoresis is considered to be useful in making a final diagnosis. Chest, abdominal and pelvic CT is considered to be useful for making a final diagnosis in solid tumors, but not for hematologic tumors. A CT-guided biopsy had a low determination rate in the final diagnosis in comparison to a laboratory analysis and CT scanning for solid tumors and it is not considered to be essential for the diagnosis of hematologic tumors.


Spine | 2006

Interlaminar bony fusion after cervical laminoplasty: its characteristics and relationship with clinical results.

Haku Iizuka; Yoichi Iizuka; Yumi Nakagawa; Takashi Nakajima; Naofumi Toda; Atsushi Shimegi; Satoshi Tsutsumi; Kenji Takagishi

Study Design. A radiographic study in 32 patients with cervical myelopathy. Objective. To investigate postoperative interlaminar bony fusion, and its characteristics and relationship to clinical results in patients undergoing laminoplasty. Summary of Background Data. Laminoplasty is being increasingly performed for multi-segmental cervical myelopathy, and its superior long-term results have been reported in some articles. We often see cases that develop postoperative interlaminar bony fusion after laminoplasty. Methods. In 32 patients, lateral cervical radiographs were obtained every year after surgery, and postoperative interlaminar bony fusion was evaluated. Range of motion (ROM) of the cervical spine at last follow-up was compared with the respective preoperative values. Furthermore, the neurologic recovery rates at last follow-up were compared to preoperative values. Results. Postoperative interlaminar bony fusion was shown in 17 patients (53%, group 1), and in most, fusion appeared within 3 years after surgery. Average age at surgery in group 1 and the remaining 15 patients (group 2) was 64.6 years and 57.0 years, respectively (P < 0.04). Preoperative and postoperative ranges of motion in group 1 were 45.6° and 28.1° on average, respectively. However, those of group 2 were 50.3° and 39.8° on average, respectively. Postoperative ROM in group 2 was significantly better maintained than that in group 1(P < 0.04). In group 1, the average preoperative Japanese Orthopedic Association score was 9.56 points, which improved to 13.6 points at the final follow-up, providing a 55.6% average recovery. In group 2, it was 10.9 points, which improved to 14.1 points at the final follow-up, providing a 56.5% average recovery. There was no significant difference in the average percentage of recovery between the 2 groups (P > 0.93). Conclusions. Postoperative interlaminar bony fusion occurred in 53% of patients, with marked frequency at C2/3 after laminoplasty. It did not influence neurologic recovery, but it did reduce the postoperative sagittal ROM of the cervical spine.


BMC Musculoskeletal Disorders | 2015

Association between neck and shoulder pain, back pain, low back pain and body composition parameters among the Japanese general population.

Yoichi Iizuka; Haku Iizuka; Tokue Mieda; Tsuyoshi Tajika; Atsushi Yamamoto; Takashi Ohsawa; Tsuyoshi Sasaki; Kenji Takagishi

BackgroundNeck and shoulder pain, back pain and low back pain are common symptoms in Japanese subjects, and it is important to elucidate the pathology and associated factors of these pains due to their frequency and impact on the quality of life (QOL) and activities of daily living (ADL). The purpose of the present study was to investigate whether body composition is associated with these pains.MethodsWe collected the data of 273 Japanese subjects regarding the presence and the visual analogue scale (VAS) of neck and shoulder pain, back pain, low back pain and body composition parameters calculated using bioelectrical impedance analysis (BIA) technology. Furthermore, we investigated the association between these pains and the body composition using statistical methods.ResultsAccording to a multivariate analysis adjusted for age and gender, lower total body water ratio was significantly associated with the presence of neck and shoulder pain at present (P < 0.05); additionally, total body muscle mass (standardized β = −0.26, 95 % CI, −0.17 - -0.008, P < 0.05), total body water (standardized β = −0.27, 95 % CI, −0.23 - -0.04, P < 0.01), appendicular muscle mass (standardized β = −0.29, 95 % CI, −0.36 - -0.04, P < 0.05), and the appendicular muscle mass index (AMI) (standardized β = −0.24, 95 % CI, −1.18 - -0.20, P <0.01) were negatively correlated with the VAS of neck and shoulder pain, whereas no body composition parameters were significantly associated with back pain, low back pain at present and any type of chronic pain.ConclusionsThe present study demonstrated that some body composition parameters regarding body water and body muscle were associated or correlated with the presence or intensity of neck and shoulder pain.


Journal of Neurosurgery | 2010

Evaluation of neck pain by using a visual analog scale before and after laminoplasty in patients with cervical myelopathy: relationship with clinical results.

Tsuyoshi Ara; Haku Iizuka; Yasunori Sorimachi; Yoichi Iizuka; Takashi Nakajima; Masahiro Nishinome; Satoshi Tsutsumi; Kenji Takagishi

OBJECT In this study the authors investigated the neck pain of patients with cervical myelopathy by using a visual analog scale (VAS) before and after laminoplasty, and they analyzed the association of amount of neck pain with the clinical results. METHODS A retrospective review was conducted in 41 patients with cervical myelopathy who underwent cervical laminoplasty. The patients were assessed using questionnaires to evaluate the neck pain intensity before surgery, and 2 years after surgery, the outcome was assessed using a VAS. The degree of cervical lordosis and range of motion (ROM) of the cervical spine were evaluated before and after laminoplasty. The neurological status was also evaluated before and after surgery. RESULTS The patients were classified into 2 groups according to their preoperative neck pain: 1) the pain (PA) group, which included patients whose preoperative VAS score was more than 1 mm; and 2) the no pain (NP) group, which included patients whose preoperative VAS score was 0 mm. Inclusion in the PA group indicated a restriction of the cervical ROM before laminoplasty; however, the improvement of neck pain in this group and the deterioration of pain status in the NP group eliminated this difference after laminoplasty. Thereafter, the PA group was classified into 2 subgroups according to the improvement of the preoperative neck pain: 1) the improved group, which included patients whose postoperative VAS score decreased; and 2) the no improvement group, which included patients who were not in the improved group. No significant differences were observed in the average recovery and radiographic results between these 2 subgroups. CONCLUSIONS Neck pain before surgery in the PA group indicated a restriction of the cervical ROM; however, the improvement of neck pain in this group and the deterioration of pain status in the NP group indicated the disappearance of this difference postoperatively. Moreover, improvement of preoperative neck pain was not associated with the radiographic results and the neurological recovery rate.


Global Spine Journal | 2017

Complications Associated With Spine Surgery in Patients Aged 80 Years or Older: Japan Association of Spine Surgeons with Ambition (JASA) Multicenter Study:

Kazuyoshi Kobayashi; Shiro Imagama; Kei Ando; Naoki Ishiguro; Masaomi Yamashita; Yawara Eguchi; Morio Matsumoto; Ken Ishii; Tomohiro Hikata; Shoji Seki; Hidetomi Terai; Akinobu Suzuki; Koji Tamai; Masaaki Aramomi; Tetsuhiro Ishikawa; Atsushi Kimura; Hirokazu Inoue; Gen Inoue; Masayuki Miyagi; Wataru Saito; Kei Yamada; Michio Hongo; Hirosuke Nishimura; Hidekazu Suzuki; Atsushi Nakano; Kazuyuki Watanabe; Hirotaka Chikuda; Junichi Ohya; Yasuchika Aoki; Masayuki Shimizu

Study Design: Retrospective study of registry data. Objectives: Aging of society and recent advances in surgical techniques and general anesthesia have increased the demand for spinal surgery in elderly patients. Many complications have been described in elderly patients, but a multicenter study of perioperative complications in spinal surgery in patients aged 80 years or older has not been reported. Therefore, the goal of the study was to analyze complications associated with spine surgery in patients aged 80 years or older with cervical, thoracic, or lumbar lesions. Methods: A multicenter study was performed in patients aged 80 years or older who underwent 262 spinal surgeries at 35 facilities. The frequency and severity of complications were examined for perioperative complications, including intraoperative and postoperative complications, and for major postoperative complications that were potentially life threatening, required reoperation in the perioperative period, or left a permanent injury. Results: Perioperative complications occurred in 75 of the 262 surgeries (29%) and 33 were major complications (13%). In multivariate logistic regression, age over 85 years (hazard ratio [HR] = 1.007, P = 0.025) and estimated blood loss ≥500 g (HR = 3.076, P = .004) were significantly associated with perioperative complications, and an operative time ≥180 min (HR = 2.78, P = .007) was significantly associated with major complications. Conclusions: Elderly patients aged 80 years or older with comorbidities are at higher risk for complications. Increased surgical invasion, and particularly a long operative time, can cause serious complications that may be life threatening. Therefore, careful decisions are required with regard to the surgical indication and procedure in elderly patients.


Global Spine Journal | 2017

Risk Factors for Delirium After Spine Surgery in Extremely Elderly Patients Aged 80 Years or Older and Review of the Literature: Japan Association of Spine Surgeons with Ambition Multicenter Study

Kazuyoshi Kobayashi; Shiro Imagama; Kei Ando; Naoki Ishiguro; Masaomi Yamashita; Yawara Eguchi; Morio Matsumoto; Ken Ishii; Tomohiro Hikata; Shoji Seki; Hidetomi Terai; Akinobu Suzuki; Koji Tamai; Masaaki Aramomi; Tetsuhiro Ishikawa; Atsushi Kimura; Hirokazu Inoue; Gen Inoue; Masayuki Miyagi; Wataru Saito; Kei Yamada; Michio Hongo; Yuji Matsuoka; Hidekazu Suzuki; Atsushi Nakano; Kazuyuki Watanabe; Hirotaka Chikuda; Junichi Ohya; Yasuchika Aoki; Masayuki Shimizu

Study Design: Retrospective database analysis. Objective: Spine surgeries in elderly patients have increased in recent years due to aging of society and recent advances in surgical techniques, and postoperative complications have become more of a concern. Postoperative delirium is a common complication in elderly patients that impairs recovery and increases morbidity and mortality. The objective of the study was to analyze postoperative delirium associated with spine surgery in patients aged 80 years or older with cervical, thoracic, and lumbar lesions. Methods: A retrospective multicenter study was performed in 262 patients 80 years of age or older who underwent spine surgeries at 35 facilities. Postoperative complications, incidence of postoperative delirium, and hazard ratios of patient-specific and surgical risk factors were examined. Results: Postoperative complications occurred in 59 of the 262 spine surgeries (23%). Postoperative delirium was the most frequent complication, occurring in 15 of 262 patients (5.7%), and was significantly associated with hypertension, cerebrovascular disease, cervical lesion surgery, and greater estimated blood loss (P < .05). In multivariate logistic regression using perioperative factors, cervical lesion surgery (odds ratio = 4.27, P < .05) and estimated blood loss ≥300 mL (odds ratio = 4.52, P < .05) were significantly associated with postoperative delirium. Conclusions: Cervical lesion surgery and greater blood loss were perioperative risk factors for delirium in extremely elderly patients after spine surgery. Hypertension and cerebrovascular disease were significant risk factors for postoperative delirium, and careful management is required for patients with such risk factors.


Journal of orthopaedic surgery | 2016

A Clinical and Ultrasonographic Study of Risk Factors for Elbow Injury in Young Baseball Players

Tsuyoshi Tajika; Tsutomu Kobayashi; Atsushi Yamamoto; Tetsuya Kaneko; Hitoshi Shitara; Daisuke Shimoyama; Yoichi Iizuka; Koichi Okamura; Yukio Yonemoto; Toshiro Warita; Takashi Ohsawa; Ichiro Nakajima; Haku Iizuka; Kenji Takagishi

Purpose. To determine the risk factors for elbow injury and its association with glenohumeral internal rotation deficit among young baseball players. Methods. 229 baseball players aged 9 to 14 (mean, 11) years completed a self-administered questionnaire with items related to years of playing baseball, hours of training per weekday, days of training per week, and past and present experience of elbow pain. Two orthopaedic surgeons measured the range of motion of both shoulders and elbows. Another 2 orthopaedic surgeons performed ultrasonography to detect any elbow abnormality such as fragmentation of the medial epicondylar apophysis and osteochondritis dissecans of the capitellum. Using univariate and multivariable analyses, participants with or without elbow abnormality were compared to determine the risk factors for elbow abnormality. Results. Elbow abnormality was detected in 100 of the participants and comprised osteochondritis dissecans of the capitellum (n=18) and fragmentation of the medial epicondylar apophysis (n=82). Elbow abnormality was associated with being a pitcher, past and present experience of elbow pain, loss of elbow extension, and the side-to-side internal rotation difference. The 100 participants with elbow abnormality were stratified into symptomatic (n=57) or asymptomatic (n=43) of elbow pain. Those with elbow abnormality and elbow pain was associated with being a pitcher. Conclusion. Being a pitcher was a risk factor for both elbow abnormality and elbow pain. Nonetheless, 43% of baseball players with elbow abnormality were asymptomatic. The use of ultrasonography was effective in detecting elbow abnormality and enabling early treatment.

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