Hisatake Yoshihara

Toyohashi Municipal Hospital, Toyohasi, Aichi, Japan

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Publications (30)58.88 Total impact

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    ABSTRACT: The goal of spinal fusion in the reconstructive spinal surgery is to achieve solid bony fusion between vertebral segments. The purpose of this study was to investigate the efficacy of low-intensity pulsed ultrasound (LIPUS) in enhancing fusion rate and bone formation after one-level posterior lumbar interbody fusion (PLIF). One-level PLIF procedure was performed in the patients with degenerative lumbar spinal stenosis between L1/2 and L5/S. Total 210 subjects were enrolled in this study prospectively, and randomly divided into 2 groups with LIPUS treatment after surgery (L-group), and without LIPUS treatment (NL-group). The patients in L-group underwent LIPUS treatment over the fusion level every day until 6 months after surgery. At week 24 and 48, the images obtained by X-ray and Dynamic computer tomography (flexion-extension CT) were evaluated. The state of bone union was classified from grade 1 (fusion) to grade 4 (non-union) in both evaluations. Finally 83 patients in L-group and 86 patients in NL-group were analyzed. According to X-ray images, 30 patients (39%) in L-group and 29 patients (37%) in NL-group were evaluated as grade 1 at 24 weeks after surgery, then 61 patients (74%) in L-group and 55 patients (66%) in NL-group at 48 weeks. While according to flexion-extension CT images, 33 patients (47%) in L-group and 36 patients (51%) in NL-group were evaluated as grade 1 at 24 weeks, then 51 patients (70%) in L-group and 42 patients (63%) in NL-group at 48 weeks. L-group showed higher fusion rate based on both radiographic and CT evaluation at 48 weeks, although the difference was not statistically significant. LIPUS therapy may promote successful fusion after spinal interbody fusion.
    Journal of orthopaedic trauma 05/2015; 29(5):S5. DOI:10.1097/01.bot.0000462963.10107.c3 · 1.54 Impact Factor
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    ABSTRACT: Objective To report a series of four cases of intradural disc herniation (IDH) with a review of the literature. Summary of background data IDH is a rare type of disc herniation. Preoperative diagnosis is difficult and IDH is only confirmed during surgery in most cases. Here, we describe four cases of IDH, including three with lumbar hernia and one with thoracic hernia. Methods A retrospective chart review, surgical database query, and review of radiology reports are presented for each case, along with a literature review of IDH. Results Two of the four patients had a history of surgery at the same spinal level. Ring enhancement in gadolinium-enhanced MRI, an air image in computed tomography, and complete block in myelography were observed in the series. Surgery was performed with a transdural approach in all patients. One patient underwent transforaminal lumbar interbody fusion after postoperative recurrence. Three patients with lumbar involvement had nerve root symptoms preoperatively, but showed symptomatic improvement in the early postoperative period. In contrast, the patient with thoracic involvement had preoperative muscle weakness due to myelopathy symptoms, and had residual symptoms after surgery. Conclusions IDH is a rare disease and characteristic imaging findings can be useful for diagnosis. Intraoperative findings lead to a definitive diagnosis in many cases and recognition of the pathological characteristics of IDH is important.
    Clinical Neurology and Neurosurgery 10/2014; 125:47–51. DOI:10.1016/j.clineuro.2014.06.033 · 1.25 Impact Factor
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    ABSTRACT: The purposes of this study were to evaluate the clinical outcome after surgical treatment of patients with the proximal type of cervical spondylotic amyotrophy (CSA) and to explore the appropriate timing for surgical intervention.
    European Journal of Orthopaedic Surgery & Traumatology 07/2014; 25(S1). DOI:10.1007/s00590-014-1504-2 · 0.18 Impact Factor
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    ABSTRACT: Object Cervical spondylosis that causes upper-extremity muscle atrophy without gait disturbance is called cervical spondylotic amyotrophy (CSA). The distal type of CSA is characterized by weakness of the hand muscles. In this retrospective analysis, the authors describe the clinical features of the distal type of CSA and evaluate the results of surgical treatment. Methods The authors performed a retrospective review of 17 consecutive cases involving 16 men and 1 woman (mean age 56.3 years) who underwent surgical treatment for the distal type of CSA. The condition was diagnosed on the basis of cervical spondylosis in the presence of muscle impairment of the upper extremity (intrinsic muscle and/or finger extension muscles) without gait disturbance, and the presence of a compressive lesion involving the anterior horn of the spinal cord, the nerve root at the foramen, or both sites as seen on axial and sagittal views of MRI or CT myelography. The authors assessed spinal cord or nerve root impingement by MRI or CT myelography and evaluated surgical outcomes. Results The preoperative duration of symptoms averaged 11.8 months. There were 14 patients with impingement of the anterior horn of the spinal cord and 3 patients with both anterior horn and nerve root impingement. Twelve patients were treated with laminoplasty (plus foraminotomy in 1 case), 3 patients were treated with anterior cervical discectomy and fusion, and 2 patients were treated with posterior spinal fixation. The mean manual muscle testing grade was 2.4 (range 1-4) preoperatively and 3.4 (range 1-5) postoperatively. The surgical results were excellent in 7 patients, good in 2, and fair in 8. Conclusions Most of the patients in this series of cases of the distal type of CSA suffered from impingement of the anterior horn of the spinal cord, and surgical outcome was fair in about half of the cases.
    Journal of Neurosurgery Spine 06/2014; 21(3):1-6. DOI:10.3171/2014.4.SPINE13681 · 2.36 Impact Factor
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    ABSTRACT: Introduction Cervical spondylotic amyotrophy (CSA) is characterized by muscle atrophy in the upper extremities without gait disturbance. However, the indications and outcomes of surgical treatment for CSA have not been clarified. The purpose of this study was to determine the risk factors for a poor outcome following surgical treatment of CSA. Materials and methods We performed a retrospective review of CSA in patients from 1991 to 2010 through a multicenter study. We collected information regarding age, type of muscle atrophy, preoperative manual muscle test (MMT), duration of symptoms, high-intensity areas on T2-weighted MR images, low-intensity areas on T1-weighted MR images, levels of spinal canal stenosis, cervical kyphosis and surgical procedures (laminoplasty, anterior cervical discectomy and fusion and posterior spinal fusion), and calculated overall risk factors related to a poor outcome following surgery. Univariate analyses and multivariate logistic regression analysis were performed to identify correlates of a poor outcome. Results Fifty-nine patients, 95 % male (56 patients), were included in our analysis with a mean age of 59 years (range 32–78 years). Eighteen patients did not improve after surgery. Symptom duration (OR = 1.263), preoperative MMT grade (OR = 0.169) and distal type of CSA (OR = 9.223) were all associated with an increased risk of a poor surgical outcome. Conclusion Early surgery is recommended for CSA patients in whom conservative treatment has not been successful. We also recommend surgery for patients who have severe preoperative muscle weakness or have the distal type of CSA.
    European Spine Journal 09/2012; 22(1). DOI:10.1007/s00586-012-2506-6 · 2.47 Impact Factor
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    ABSTRACT: To clarify the relative frequency of various histopathological primary spinal cord tumors and their features in Japanese people and to compare this data with other reports. Primary spinal cord tumor surgical cases from 2000 to 2009, which were registered in our affiliated hospital database were collected. We examined age at surgery, sex, anatomical location, vertebral level of the tumor, and pathological diagnosis in each case. Of the 678 patients in our study, 377 patients (55.6 %) were males and 301 patients (44.4 %) were females (male/female ratio 1.25). The mean age at surgery was 52.4 years. Of these tumors, 123 cases (18.1 %) were intramedullary, 371 cases (54.7 %) were intradural extramedullary, 28 cases (4.1 %) were epidural, and 155 cases (22.9 %) were dumbbell tumors. The pathological diagnoses included 388 schwannomas (57.2 %), 79 meningiomas (11.6 %), 54 ependymomas (8.0 %), 27 hemangiomas (4.0 %), 23 hemangioblastomas (3.4 %), 23 neurofibromas (3.4 %), and 9 astrocytomas (1.3 %). The male/female ratios for schwannomas, meningiomas, ependymomas, hemangiomas, hemangioblastomas, neurofibromas, malignant lymphomas, and lipomas are 1.4, 0.34, 1.3, 1.5, 2.3, 1.3, 2.7 and 2.3, respectively. This is the first published research in English on the epidemiology of primary spinal cord tumors in Japanese people. Similar to other reports from Asian countries, our data indicates a higher male/female ratio overall for spinal cord tumors, a higher proportion of nerve sheath cell tumors, and a lower proportion of meningiomas and neuroepithelial tumors compared to reports from non-Asian countries. Data in the current study represent the characteristics of primary spinal cord tumors in Asian countries.
    European Spine Journal 05/2012; 21(10):2019-26. DOI:10.1007/s00586-012-2345-5 · 2.47 Impact Factor
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    ABSTRACT: Atlantoaxial instability (AAI) is an uncommon disease in children. Surgical treatment of pediatric patients with AAI poses a challenge to spine surgeons because of the patients' immature bone quality, extensive anatomical variability, and smaller osseous structures. In this study, the authors report complications and outcomes after posterior fusion in children with AAI. The authors reviewed medical records of patients 13 years old and younger with AAI who underwent posterior fusion in the Nagoya Spine Group hospitals, a multicenter cooperative study group, from January 1995 to December 2007. We identified 11 patients who underwent posterior fusion, and analyzed their clinical outcomes and complications. To determine if vertical growth within the construct continued after posterior fusion, in three patients at 5 or more years following occipito-cervical (O-C) fusion, intervertebral disc heights and vertebral heights between the fused and non-fused levels were compared on the final follow-up. The initial surgeries were C1-C2 fusions in six patients and O-C fusion in five patients. Successful fusion ultimately occurred in all patients, however, the complication rate related to the operations was high (64%). Complications included neurologic deterioration, pedicle fracture with pedicle screw insertion, C1 posterior arch fracture with lateral mass screw insertion, perforation of the skull with a head pin placement, and fusion extension to adjacent vertebrae. Two patients required reoperation. The mean fixed and non-fixed intervertebral disc heights on the final follow-up were 2.6 and 5.3 mm, respectively, showing that the disc height of the fixed level was less than the non-fused level. Each vertebra lengthened similarly between fused and non-fused levels except for C2 which had a lower growth rate than the other vertebrae. A high complication rate should be anticipated after posterior fusion in children with AAI. Careful consideration should be paid to pediatric patients with AAI treated by screw and/or rod systems. After posterior fusion in pediatric patients, each vertebra continued to grow, in contrast the disc height decreased between fused levels.
    European Spine Journal 11/2011; 21(7):1346-52. DOI:10.1007/s00586-011-2083-0 · 2.47 Impact Factor
  • R Tauchi · S Imagama · T Kanemura · H Yoshihara · K Sato · M Deguchi · M Kamiya · N Ishiguro
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    ABSTRACT: We reviewed seven children with torticollis due to refractory atlanto-axial rotatory fixation who were treated in a halo vest. Pre-operative three-dimensional CT and sagittal CT imaging showed deformity of the superior articular process of C2 in all patients. The mean duration of halo vest treatment was 67 days (46 to 91). The mean follow-up was 34 months (8 to 73); at the latest review six patients demonstrated remodelling of the deformed articular process. The other child, who had a more severe deformity, required C1-2 fusion. We suggest that patients with atlanto-axial rotatory fixation who do not respond to conservative treatment and who have deformity of the superior articular process of C2 should undergo manipulative reduction and halo-vest fixation for two to three months to induce remodelling of the deformed superior articular process before C1-2 fusion is considered.
    The Bone & Joint Journal 08/2011; 93(8):1084-7. DOI:10.1302/0301-620X.93B8.26803 · 2.80 Impact Factor
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    ABSTRACT: Pinealectomy was used to induce scoliosis in Broiler chickens, and the bone microarchitecture of the concave and convex sides in pinealectomized scoliosis chickens was assessed by microcomputed tomography (micro-CT). Few studies have assessed the vertebrae bone microarchitecture of the concave and convex sides in scoliosis although the curvature of the coronal plane is the main deformity in scoliosis. The purpose of this study was to determine whether there are differences in the bone microarchitecture of the concave and convex sides in pinealectomized scoliosis chickens by the technique of micro-CT. The etiology and the pathogenesis of the idiopathic scoliosis remain unclear. Limited information is available on the microarchitecture of vertebrae bone of the concave and convex sides of scoliosis, especially in the earlier stage in scoliosis development. One hundred female Broiler chickens were divided into three groups as follows: the control group (n=20), the sham operation group (n=20), and the pinealectomy group (n=60). Then the pinealectomy group was divided into three groups according to the time of killing the chickens: 1-week after the operation (group P-1 w, n=20), 2 weeks after the operation (group P-2 w, n=20), and 3 weeks after the operation (group P-3 w, n=20), respectively. Posteroanterior radiographs of the spine were taken to detect spinal curvature. Using micro-CT, the bone volume/tissue volume (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular separation of the concave and convex sides of the apex vertebrae in the scoliotic chickens were determined. Independent t-tests were used to assess differences of bone parameter of the concave and convex sides in each pinealectomized group. The incidences of scoliosis in the pinealectomized Broiler chickens were 84.2% (group P-1 w), 88.9% (group P-2 w), and 89.5% (group P-3 w), respectively. In groups P-1 w and P-2 w, there were no differences between the concave and convex trabecular bone microarchitectures. In group 3 w, the BV/TV, Tb.Th, and Tb.N of the concave side were significantly greater than those of the convex side. In the earlier stage of pinealectomized scoliosis chickens, there are no histological evidence of a metabolic abnormality. The greater BV/TV, Tb.Th, and Tb.N of the concave side in group P-3 w may be consistent with Wolff's law and are the secondary response to the scoliotic deformity.
    Journal of pediatric orthopaedics. Part B / European Paediatric Orthopaedic Society, Pediatric Orthopaedic Society of North America 07/2011; 20(6):382-8. DOI:10.1097/BPB.0b013e3283474c6e · 0.66 Impact Factor
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    ABSTRACT: Prospective, multicenter study. To conduct peripheral arterial disease (PAD) screening on intermittent claudication (IC) in patients with lumbar spinal canal stenosis (LSCS) to examine the relationships among combined LSCS and PAD, symptoms, and physical findings. IC occurs due to two underlying diseases, LSCS and PAD, and has an increasing prevalence with the aging of society. Reliable diagnosis of PAD is critical for appropriate conservative management of IC patients with LSCS in an Orthopedic Surgery Outpatient Department (OSOPD). PAD tests were prospectively conducted in 201 patients with IC and LSCS who initially visited an OSOPD at a hospital affiliated with the Nogoya Spine Group. Occurrence of PAD as a complication was assessed using ankle brachial pressure index (ABI) and toe brachial pressure index (TBI) tests. PAD was diagnosed in patients with ABI ≤ 0.9 or TBI ≤ 0.6, and the relationship of the occurrence of PAD with symptoms and physical findings such as abnormal arterial pulses was investigated. Combined LSCS and PAD was found in 52 patients (26%), with 45 cases (22%) diagnosed on the basis of TBI test in patients with a normal ABI. Of the patients with PAD, many suffered from risk factors for PAD, with a significantly higher frequency of PAD in patients with hyperlipidemia (P < 0.05). PAD also occurred significantly more frequently in patients with abnormal pulses in the popliteal (P < 0.05), posterior tibial (P < 0.0001), and dorsal pedis (P < 0.0001) arteries; however, the sensitivity of these tests for PAD diagnosis was relatively low, at 34%, 60% and 68%, respectively. The results of the prospective study define the rate of occurrence of combined LSCS and PAD using ABI and TBI tests for the first time, and the findings suggest that screening for PAD should be conducted in LSCS patients. ABI and TBI tests are necessary for PAD screening in outpatients, whereas observation of the arterial pulse in the lower extremities is necessary but not sufficient for PAD diagnosis.
    Spine 07/2011; 36(15):1204-10. DOI:10.1097/BRS.0b013e3181ebd86f · 2.45 Impact Factor
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    ABSTRACT: The purpose of this study was to evaluate the effect of a fixed atlantoaxial angle on subaxial sagittal alignment, and that of atlantoaxial fixation on adjacent-segment motion and degeneration. The authors retrospectively reviewed 65 patients in whom atlantoaxial instability was treated with atlantoaxial fixation by C-1 lateral mass and C-2 pedicle screw fixation (30 patients, Goel-Harms [GH] group) or a combination of transarticular screw fixation and posterior wiring (35 patients, Magerl-Brooks [MB] group). Angles of Oc–C1, C1–2, C2–3, and C2–7 were determined based on an upright lateral radiograph in flexion, neutral, and extension positions. The range of motion (ROM) at Oc–C1 and C2–3 was also determined. All patients were examined before and 2 years after surgery. The mean preoperative atlantoaxial angles in the GH and MB groups were 20.9 ± 8.3° and 18.3 ± 7.2°, respectively, and the mean postoperative atlantoaxial angles in the same groups were 23.5 ± 5.6° and 29.7 ± 6.3°, respectively, with a statistically significant difference between the 2 groups (p < 0.05). The mean preoperative angles of C2–7 in the GH and MB groups were 15.4 ± 7.8° and 13.7 ± 9.5°, respectively, and after surgery, the angles were 11.8 ± 12° and 2.48 ± 12°, respectively, with a statistically significant difference between the 2 groups (p < 0.05). The postoperative angle of C1–2 showed a negative correlation with the extent of change observed in the C2–7 angle pre- and postoperatively in each of these 2 surgical procedures. The Oc–C1 ROM increased after surgery in both groups, but the difference was not statistically significant (p = 0.38). The C2–3 ROM decreased after surgery in both groups, and the difference was statistically significant (p < 0.05). Atlantoaxial fixation in a hyperlordotic position produced kyphotic sagittal alignment after surgery in both GH and MB groups. Reduction of the atlantoaxial joint can be easily achieved through screw fixation at an optimal angle, thereby ameliorating the risk for subsequent subaxial kyphosis. Degeneration of lower adjacent segments appeared to be less with this procedure compared with using a combination of transarticular screw fixation and posterior wiring.
    Journal of neurosurgery. Spine 10/2010; 13(4):443-50. DOI:10.3171/2010.4.SPINE09662 · 2.36 Impact Factor
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    ABSTRACT: Retrospective clinical study. The objective of this study is to evaluate the clinical outcome of occipitothoracic fusion for severe destructive cervical lesions in rheumatoid arthritis (RA) patients with myelopathy and/or occipitocervical pain, and to discuss surgical complications. The complication rates are compared between 2 groups treated with different instrumentation techniques. Few studies have reported on the results of occipitothoracic fusion in RA patients. In this study, 56 RA patients with myelopathy and/or occipitocervical pain caused by destructive cervical lesions were studied. The patients were divided into 2 groups A and B, according to the used rod diameter and the application of the cervical pedicle screw system. Group A included 38 patients treated with Unit rods (4.75 mm). Group B included 18 patients treated with cervical pedicle screw system (3.2 mm or 3.5 mm diameter rod). Clinical results and surgical complications were evaluated. Mean follow-up time was 36.2 months. Fifteen patients died during follow-up at the mean age of 67.3 years. None died from their cervical lesions. The neurologic status in 46 patients (82%) had improved at least 1 class in the modified Ranawat scale. Perioperative complications occurred in 16 (28.6%), thoracic spine lesions in 11 (19.6%), implant failure in 13 (23.2%), and surgical site infection in 8 (14.3%). There was a tendency for more fractures and pedicle screw pullouts at the lowest level of the fusion area to occur in group B. The neurologic improvement of patients undergoing occipitothoracic fusion after becoming unable to sit owing to their neurologic deficit was poor. The current study suggests that occipitothoracic fusion for rheumatoid destructive cervical lesions can be effective in improving neurologic deficit if performed while patients can still sit. Improvements to methodology of this surgery can be made.
    Journal of spinal disorders & techniques 04/2010; 23(2):121-6. DOI:10.1097/BSD.0b013e3181993315 · 1.89 Impact Factor
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    ABSTRACT: The purpose of this study was to provide the first evidence for image classification of idiopathic spinal cord herniation (ISCH) in a multicenter study. Twelve patients who underwent surgery for ISCH were identified, and preoperative symptoms, severity of paralysis and myelopathy, disease duration, plain radiographs, MR imaging and CT myelography findings, surgical procedure, intraoperative findings, data from spinal cord monitoring, and postoperative recovery were investigated in these patients. Findings on sagittal MR imaging and CT myelography were classified into 3 types: a kink type (Type K), a discontinuous type (Type D), and a protrusion type (Type P). Using axial images, the location of the hiatus was classified as either central (Type C) or lateral (Type L), and the laterality of the herniated spinal cord was classified based on correspondence (same; Type S) or noncorrespondence (opposite; Type O) with the hiatus location. A bone defect at the ISCH site and the laterality of the defect were also noted. Patients with Type P herniation had a good postoperative recovery, and those with a Type C location had significant severe preoperative lower-extremity paralysis and a significantly poor postoperative recovery. Patients with a bone defect had a significantly severe preoperative myelopathy, but showed no difference in postoperative recovery. The authors' results showed that a Type C classification and a bone defect have strong relationships with severity of symptoms and surgical outcome and are important imaging and clinical features for ISCH. These findings may allow surgeons to determine the severity of preoperative symptoms and the probable surgical outcome from imaging.
    Journal of Neurosurgery Spine 09/2009; 11(3):310-9. DOI:10.3171/2009.4.SPINE08691 · 2.36 Impact Factor
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    ABSTRACT: The objectives of this study were to determine whether recombinant human bone morphogenetic protein-2 (rhBMP-2) can be used as the sole stimulator of osteogenesis with success equal to an autologous graft in posterolateral lumbar fusion (PLF) at the same level and to describe the progress until bone union. This study included 11 patients who underwent PLF of L4-5. On the right side, only rhBMP-2, for which polylactic/glycolic acid (PLGA) was used as a carrier, was used, whereas, on the left side, autogenous bone was used. The bone union rate was 73 and 82% at 12 and 24 months after surgery, respectively, on the right BMP side, while the rate on the autogenous bone side was 91%. There was no statistically significant difference in the bone union rate. rhBMP-2 can be used as the sole source of osteogenesis with success equivalent to an autologous graft of the PLF.
    International Orthopaedics 07/2008; 33(4):1061-7. DOI:10.1007/s00264-008-0600-5 · 2.02 Impact Factor
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    Yasutsugu Yukawa · Fumihiko Kato · Hisatake Yoshihara · Makoto Yanase · Keigo Ito
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    ABSTRACT: Prospective imaging study of patients undergoing surgery for cervical compressive myelopathy. OBJECTIVES.: To investigate whether the classification of increased signal intensity (ISI) on magnetic resonance imaging (MRI) in patients with cervical compressive myelopathy reflects the severity of symptoms and surgical outcome. The association between ISI and surgical outcome in cervical myelopathy remains controversial. The degree of ISI has not been well discussed. A total of 104 patients with cervical compressive myelopathy were prospectively enrolled. All were treated with cervical expansive laminoplasty. MRI was performed in all patients before surgery. ISI of spinal cord was classified into three groups based on sagittal T2-weighted images as follows: Grade 0, none; Grade 1, light (obscure); and Grade 2, intense (bright). The severity of myelopathy was evaluated according to the Japanese Orthopedic Association (JOA) score for cervical myelopathy. Eighty-six patients (83%) showed ISI before surgery. Patients with ISI were significantly older, and had a longer duration of disease, a lower postoperative JOA score, and a worse postoperative recovery rate of JOA score than those without ISI. Preoperative MRI showed 18 patients in Grade 0, 49 patients in Grade 1, and 37 in Grade 2. Duration of disease was the shortest in Grade 0 and longest in Grade 2. Although there was no significant difference in preoperative JOA scores among the three groups, Grade 0 patients had a higher postoperative JOA score and the best postoperative recovery, and Grade 2 had a lower postoperative JOA score and the worst postoperative recovery. Preoperative ISI on T2-weighted sagittal MRI was correlated with patient age, duration of disease, postoperative JOA score, and postoperative recovery rate. Patients with the greatest ISI had the worst postop erative recovery. Classification of ISI can be a predictor of surgical outcome.
    Spine 08/2007; 32(15):1675-8; discussion 1679. DOI:10.1097/BRS.0b013e318074d62e · 2.45 Impact Factor
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    ABSTRACT: Cross-sectional cohort study of elderly people. To examine the factors influencing osteophyte formation without lumbar disc degeneration and to estimate the implications of osteophytes from the viewpoint of low back pain and gene polymorphisms. The degenerative changes that occur in the intervertebral discs are the point of departure of osteophyte formation. Several studies on factors associated with genetic susceptibility to spinal osteophyte formation, such as VDR and TGF-beta1. However, there are no detailed studies concerning osteophytes not accompanied with disc degeneration. A total of 387 elderly persons were recruited, and disc degeneration and osteophyte formation were evaluated. The cases with osteophyte formation were classified into 3 groups: osteophyte formation with disc height narrowing (n = 217), osteophyte formation without disc height narrowing (n = 99), and control group defined as the cases without osteophyte formation (n = 71). Twelve genotypes were characterized. Correlations between these degenerative factors and the polymorphisms were analyzed. The prevalence of low back pain was significantly greater in the group of osteophyte formation with disc height narrowing than the other 2 groups. In the polymorphism of alcohol dehydrogenase (ADH2), prevalence of osteophyte formation without disc height narrowing was less in His/Arg (odds ratio = 0.57, P = 0.041) and Arg/Arg (odds ratio = 0.41, P = 0.18) than His/His. Patients with osteophyte formation preceding intervertebral disc narrowing had a lower risk of low back pain compared with those without osteophytes. The 47Arg polymorphism in the ADH2 may act to suppress osteophyte formation unaffected by disc degeneration.
    Spine 06/2007; 32(12):1279-86. DOI:10.1097/BRS.0b013e318059af8a · 2.45 Impact Factor
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    Yasutsugu Yukawa · Fumihiko Kato · Hisatake Yoshihara · Makoto Yanase · Keigo Ito
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    ABSTRACT: The authors conducted a study to introduce the imaging technique in which pedicle axis views are obtained using fluoroscopy to match the screw entry point with pedicle orientation and to report the clinical results and safety of cervical pedicle screw fixation (PSF) in patients treated for unstable cervical injuries. One hundred consecutive patients with unstable cervical injuries underwent PSF in which the authors used fluoroscopic imaging to acquire pedicle axis views. There were 87 men and 13 women whose mean age was 42.5 years. The accuracy of PS placement was examined postoperatively using axial computed tomography (CT) and oblique radiography. Screw malpositioning was classified either as screw exposure (< 50% of the screw outside the pedicle) or pedicle perforation (> 50% of the screw outside the pedicle boundaries). The mean operative time was 97.6 minutes, and the mean estimated blood loss was 221 ml. Local vertebral alignment around the injured segment measured 6.0 degrees of kyphosis preoperatively and 6.7 degrees of lordosis postoperatively. Solid posterior bone fusion was achieved in all but three patients who died shortly after surgery. There was no secondary dislodgment of instrumentation in 95% of these 97 cases. Of the 419 cervical PSs, 43 (10.3%) were of the screw-exposure type and 17 (4.0%) of the pedicle-perforation type. There were two surgery-related complications: one penetration of a probe into the vertebral artery and one radiculopathy. There were six postoperative complications: two cases of instrumentation failure associated with loss of correction, three cases of correction loss (> 10 degrees), and one case of deep wound infection. Solid posterior fusion without secondary dislodgment of hardware was demonstrated in 95% of the cases. The incidence of complications associated with cervical PSF was not high. Postoperative CT scanning showed that 17 (4.0%) of 419 screws perforated the pedicle. It appears that fluoroscopy performed using pedicle axis views improves the accuracy and safety of cervical PS insertion.
    Journal of Neurosurgery Spine 12/2006; 5(6):488-93. DOI:10.3171/spi.2006.5.6.488 · 2.36 Impact Factor
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    ABSTRACT: A prospective study was conducted on the surgical procedures for lumbar disc herniation. The objective of this study is to investigate the surgical outcomes of different methods when performed by the same surgeon, using a prospective study. Macro discectomy is widely known as a common surgical procedure for lumbar disc herniation, while microdiscectomy in place of Caspar technique (the Caspar method) and microendoscopic discectomy by a posterior approach are reported as less invasive surgical methods for this condition. However, there have not been a significant number of prospective studies conducted to compare different surgical procedures for lumbar disc herniation. The target of our study was a group of 62 patients (male: 43, female: 19) who underwent surgery by macro discectomy (A group) and 57 patients (male: 33, female: 24) who underwent surgery by microdiscectomy in place of Caspar technique (B group). The mean ages at surgery were 34 (14 to 62) years and 41 (18 to 65) years respectively, and the mean duration of follow-up was 2 years and 8 months (12 months to 4 years). For all patients, the surgery was performed by 1 of the authors. The items investigated were the operation time, amount of bleeding, duration of hospitalization, amount of analgesic agent used after surgery, pre- and postoperative scores based on judgment criteria for treatment of lumbar spine disorders established by the Japanese Orthopaedic Association score, visual analog scales (VAS, 0 to 10) for lumbago before surgery and at discharge, VAS for sciatica before surgery and at discharge, perioperative complications, and cases requiring further surgery. There were no significant differences between the 2 surgical procedures in the frequency of use of an analgesic agent after surgery, the pre- and postoperative Japanese Orthopaedic Association scores or postoperative VAS for sciatica. Statistically significant differences were observed in the operation time, amount of bleeding, duration of hospitalization, and postoperative VAS for lumbar pain, but the differences were not large, and may not have been clinically significant. For herniotomy for lumbar disc herniation, both macro discectomy and microdiscectomy are appropriate, as long as surgeons have mastery of the procedures.
    Journal of Spinal Disorders & Techniques 08/2006; 19(5):344-7. DOI:10.1097/01.bsd.0000211201.93125.1c · 1.89 Impact Factor
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    ABSTRACT: Computer-assisted surgery, which provides simultaneous, multiplanar images of bone structures, has become widely used. However, registration maneuvering remains time consuming. The objective of this paper is to document the usefulness of CT-fluoro matching for spinal navigation. A spinal navigation system (VECTORVISION compact; Brain LAB, Germany) and a digital imaging system (OEC9800; CATHEX, Tokyo, Japan) were used for CT-fluoro matching in cases of L4/5 and L5/S1 posterior lumbar interbody fusion. A reference array was attached to the L4 spinous process. Preoperative CT images and intraoperative fluoro-shots including L4, L5, and S1 were superimposed on the navigation monitor. Following insertion of L4 screws, a reference array remained to be attached to the L4 spinous process, after which a level definition and pre-registration of L5 and S1 vertebrae were performed and the screwing procedure of L5 and S1 was completed without additional fluro-shots. Registration of three vertebrae was completed without paired-point or surface-matching procedures. The calculation time for the registration in a single vertebra was 30 sec. All pedicle screws were seen to be successfully inserted on postoperative CT images. We performed the navigation surgery by matching the preoperative CT images to the intraoperative fluoro-shots without manual registration. This technique may prove useful in the future for anterior spinal surgery and percutaneous screwing without the need for total exposure of the bone surface.
    Nagoya journal of medical science 02/2006; 68(1-2):45-52. · 0.80 Impact Factor
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    ABSTRACT: Ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine produces myelopathy through anterior spinal cord compression that is usually progressive and unaffected by conservative treatment. Therefore, early decompressive surgery is imperative. However, decompression surgery of thoracic myelopathy is difficult, and the outcome is often poor. A retrospective study was conducted to investigate the surgical outcome of 21 patients with thoracic OPLL to evaluate which type of surgical approach is better and which type of thoracic OPLL results in a better surgical outcome. A total of 21 patients with thoracic OPLL (10 men and 11 women; mean age 54 years), who underwent surgical treatment at our department from March 1985 to October 2000, were included in the study. Seven patients exhibited the flat-type OPLL and underwent either anterior decompression and fusion (one patient), anterior decompression via a posterior approach (three patients), or expansive laminoplasty (three patients). Fourteen patients exhibited the beak-type OPLL and also underwent either anterior decompression and fusion (two patients), anterior decompression via a posterior approach (six patients), or expansive laminoplasty (six patients). Regarding of operative time and blood loss, there were no marked differences between the two types of OPLL, regardless of the type of surgical procedure; anterior decompression and fusion and anterior decompression via a posterior approach yielded longer operative times and larger blood loss volumes than expansive laminoplasty. Concerning clinical outcome, there were five cases of neurologic deterioration. All of the five deteriorated cases were of the beak-type OPLL treated by a posterior approach. Two of these patients were treated with expansive laminoplasty. There were five instances of neurologic deterioration in our thoracic OPLL series, and all of them exhibited beak-type OPLL. In the beak-type OPLL, a subtle alteration in the spinal alignment during posterior decompression procedures may increase spinal cord compression, leading to the deterioration of symptoms. A potential increase in kyphosis following laminectomy should be avoided by fixation with a temporary rod. If intraoperative monitoring suggests spinal cord dysfunction, an anterior decompression procedure should be attempted as soon as possible.
    Journal of Spinal Disorders & Techniques 01/2006; 18(6):492-7; discussion 498. DOI:10.1097/01.bsd.0000155033.63557.9c · 1.89 Impact Factor

Publication Stats

433 Citations
58.88 Total Impact Points

Institutions

  • 2011–2014
    • Toyohashi Municipal Hospital
      Toyohasi, Aichi, Japan
  • 2004–2011
    • Nagoya University
      • Division of Orthopedics Surgery
      Nagoya, Aichi, Japan
  • 2006–2007
    • Chubu Rosai Hospital
      Nagoya, Aichi, Japan