Spine Surgery and Related Research
Online ISSN : 2432-261X
Advance online publication
Showing 1-31 articles out of 31 articles from Advance online publication
  • Chikara Ushiku, Kota Suda, Satoko Matsumoto, Miki Komatsu, Masahiko Ta ...
    Article ID: 2018-0009
    Published: 2018
    [Advance publication] Released: July 25, 2018
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    Introduction: Cervical spinal cord injury without bone injury (SCIWOBI) is a common cervical injury in the elderly population and is most likely to occur at the C3/C4 level. Respiratory dysfunction (RD) related to the damage of the spinal respiratory center, which is close to the C4 segment, is one of the greatest obstacles in improving the activities of daily living of patients with severe paralysis. We evaluated the time course of RD and motor function in cervical SCIWOBI to identify effective medical strategies.

    Methods: We followed 54 patients (49 men, 5 women; mean age: 65 years old) who were treated for SCIWOBI at our medical center from 2011 to 2014. The patients were evaluated within 72 hours of injury and were monitored for at least 12 weeks. All patients began respiratory-muscle training the day after admission regardless of whether they were treated conservatively or surgically. The percent vital capacity (%VC), forced expiratory volume (FEV) in one second/forced vital capacity ratio (FEV 1.0%), and American Spinal Injury Association motor score (MS) were recorded at admission and again at weeks 4 and 12. We calculated the %VC rate of change and the MS improvement rate over the entire period.

    Results: Fifty patients (92.6%) had restrictive ventilatory impairment at admission. The %VC correlated with the upper- and lower-limb MSs at admission, and the %VC and upper- and lower-limb MSs had improved by weeks 4 and 12 after the injury. The %VC rate of change was significantly correlated with the rate of improvement in lower-limb MS throughout the entire period.

    Conclusions: Lung capacity decreased in SCIWOBI owing to respiratory-muscle paralysis and upper- and lower-limb motor paralyses. Lung capacity improved as the lower limbs recovered their motor function. Respiratory rehabilitation should be continued for at least 12 weeks after SCIWOBI.

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  • Toshinori Sakai, Tsuyoshi Goto, Kosuke Sugiura, Hiroaki Manabe, Fumita ...
    Article ID: 2018-0012
    Published: 2018
    [Advance publication] Released: July 25, 2018
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    Introduction. Although there has been a dramatic improvement in the outcomes of conservative treatment to achieve bony healing due to advances in diagnostic and therapeutic tools, in some patients, the results continue to be unfavorable. The purpose of this study was to investigate the outcomes of conservative treatment in pediatric patients with stress fractures occurring in the lamina that are discontinuous due to a contralateral pars defect or spina bifida occulta (SBO).

    Methods. The medical records at our outpatient clinic for 103 consecutive patients (83 boys, 20 girls) with lumbar spondylolysis (LS) were reviewed to identify those who had presented with a stress fracture and a contralateral pars defect or with SBO at the affected lamina level.

    Results. Twelve patients (11 boys, 1 girl) of mean age 12.3 (range 8–16) years were identified. Except for1 stress structure that occurred at L4, all the stress fractures occurred at L5. Six patients had a pars defect, 5 had SBO, and 1 had both. Two of the 6 patients with a contralateral pars defect had early LS, 3 had progressive LS, and 1 had a pedicle fracture. The fracture healed in1 (50%) of the 2 patients with early LS and in the patient with the pedicle fracture, but did not heal in any of the patients with progressive LS. Two of the 5 patients with SBO at the affected lamina level had early LS and 3 had progressive LS. The bony healing rate was 100% in the 2 patients with early LS and 66.7% in the 3 patients with progressive LS. The fracture healed in the patient with progressive LS and both a pars defect and SBO at the affected lamina.

    Conclusion Contralateral pars defect remains an unfavorable factor for bony healing discontinuous laminar stress fractures.

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  • Yohei Ishihara, Masutaro Morishita, Jiro Miyaki, Koji Kanzaki, Tomoaki ...
    Article ID: 2018-0022
    Published: 2018
    [Advance publication] Released: July 25, 2018
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    Introduction: This study aimed to compare the clinical and radiological results of transforaminal lumbar interbody fusion (TLIF) with a boomerang-shaped cage and traditional posterior lumbar interbody fusion (PLIF) according to fused level and elucidate whether TLIF could replace PLIF at all lumbar levels.

    Methods: The study investigated 128 patients with lumbar spondylolisthesis who underwent a single-level TLIF or traditional PLIF. Intraoperative blood loss, operative time, and recovery rate were analyzed. Percent slip, disc height, and local lordosis at the fused level were measured using X-ray images from preoperation to the final follow-up.

    Results: No significant differences in recovery rate were observed at any level. The operative time and intraoperative blood loss were significantly less in the TLIF group at the L4/5 and L5/S1 levels. There were no significant differences in disc height or local lordosis at the L3/4 and L4/5 levels, and a satisfactory level of maintenance after the operation was achieved in both groups. However, at the L5/S1 level, postoperative maintenance after TLIF could not be achieved, and the obtained disc height and local lordosis in TLIF significantly decreased.

    Conclusions: Compared with traditional PLIF, TLIF was a less invasive procedure with a shorter operative time and lesser blood loss. TLIF could obtain similar local lordosis and disc height as PLIF at the L3/4 and L4/5 levels. At the L5/S1 level, the postoperative maintenance of local lordosis and disc height after TLIF was inferior to that after PLIF. On the basis of our results, we do not recommend performing TLIF at only the L5/S1 level.

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  • Takashi Hirai, Takashi Taniyama, Toshitaka Yoshii, Koichi Mizuno, Miki ...
    Article ID: 2018-0027
    Published: 2018
    [Advance publication] Released: July 25, 2018
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    Introduction We describe 5 patients who underwent operative treatment for arachnoid web (AW) and discuss the postoperative clinical outcome in each case. AW is an extremely rare disease that causes cord compression and syringomyelia in the thoracic spine. To date, 14 cases only of AW have been reported, and the effect of surgical intervention on clinical and radiologic outcomes is unknown.

    Methods: Five patients who underwent surgical treatment for AW were retrospectively reviewed. The clinical outcomes were evaluated using the thoracic Japanese Orthopaedic Association (T-JOA) score. Preoperative and postoperative images were reviewed.

    Results: All the patients presented with spastic gait and numbness in the lower extremities. Two patients also presented with bladder-bowel dysfunction (BBD). AW, or the so-called "scalpel" sign, was seen dorsally in the thoracic spine on magnetic resonance imaging in all the patients. Syringomyelia adjacent to the web was observed in 4 patients. Fenestration and web resection without instrumentation was performed in all the cases. Overall, significant improvement was seen in locomotion and the total T-JOA score postoperatively. However, numbness in the lower extremities improved in 2 patients but was unchanged in 3. BBD was ameliorated in 1 patient but remained unchanged in the other patient.

    Conclusions: Our experience suggests that surgical treatment, including fenestration and resection of the web, can correct the flow dynamics of cerebrospinal fluid and allow neurologic recovery, in particular locomotion, in patients with AW.

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  • Toshio Nakamae, Kiyotaka Yamada, Yasuyuki Tsuchida, Nobuo Adachi, Yosh ...
    Article ID: 2018-0035
    Published: 2018
    [Advance publication] Released: July 25, 2018
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    Introduction:

    Spinal lesions in synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome generally have a good prognosis and rarely cause structural destruction or neurological deterioration. We described a surgical case of posterior instrumented surgery without anterior reconstruction and bone graft in a patient with SAPHO syndrome with destructive spondylitis and reviewed the literature on surgical treatment for this entity.

    Case Report:

    We describe the case of a 73-year-old male who presented with palmoplantar pustulosis. He experienced progressive low back and leg pain for the past 3 months. Destructive spondylitis and lumbar canal stenosis were detected with magnetic resonance imaging (MRI), and aspiration biopsy was used to exclude pyogenic spondylitis and spinal tumors. He underwent posterior decompression and fixation surgery without anterior reconstruction and bone grafting. Low back and leg pain improved after surgery. Postoperative radiography and computed tomography showed boney bridge between vertebral bodies, and MRI showed the decrease of bone marrow edema.

    Conclusions:

    Posterior fusion without anterior reconstruction produced a bony bridge between the vertebral bodies. Taking the pathophysiology of SAPHO syndrome into consideration, anterior reconstructed fusion for patients with SAPHO syndrome might not be needed.

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  • Hiroaki Nakashima, Tokumi Kanemura, Kei Ando, Kazuyoshi Kobayashi, Min ...
    Article ID: 2018-0003
    Published: 2018
    [Advance publication] Released: June 29, 2018
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    Background: Nonsteroidal anti-inflammatory drugs (NSAIDs) are the first-line treatment for acute lumbar radicular pain accompanying lumbar disc herniation (LDH), but their effects are minimal. The purpose of this study was to evaluate the efficacy and safety of pregabalin (PGB) as an alternative therapy for this condition.

    Methods: Patients with acute lumbar radicular pain accompanying LDH were randomly administered either NSAIDs plus PGB (30 patients) or NSAIDs alone (30 patients) for up to 4 weeks. The primary outcome was leg pain at 2 and 4 weeks. Secondary outcomes were reduction in sleep disturbances and patient global impressions of change (PGIC) at 2 and 4 weeks.

    Results: Four patients in the NSAIDs plus PGB group were deemed ineligible and excluded from the study. Fewer sleep disturbances were reported by patients administered NSAIDs plus PGB compared with the NSAID monotherapy group at both 2 and 4 weeks. Additionally, the NSAIDs plus PGB group showed greater improvement in pain than the NSAID monotherapy group at 4 weeks, although this difference was not significant. PGIC was also significantly better in the NSAIDs plus PGB group than in the NSAID monotherapy group at 4 weeks. The incidence of adverse events was significantly greater in the NSAIDs plus PGB group than in the NSAID monotherapy group.

    Conclusions: The combination of NSAIDs plus PGB is more effective against sleep disturbance than NSAIDs alone in patients with acute LDH, although the control of sciatic pain is minimal. Patients reported satisfactory recoveries could also be obtained, and thus, this combination therapy could be a good option for the conservative treatment of acute lumbar radicular pain, including LDH.

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  • Kazunari Takeuchi, Toru Yokoyama, Kan-ichiro Wada, Hitoshi Kudo
    Article ID: 2018-0008
    Published: 2018
    [Advance publication] Released: June 29, 2018
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    Introduction. The purpose of this study was to investigate the relationship between postoperative enlargement of the dural sac cross-sectional area at the symptomatic level and neurological improvements after laminoplasty.

    Methods. The cross-sectional areas of the dural sac at the symptomatic level before and after laminoplasty and the expansion ratio (post-/preoperative cross-sectional area) were measured using magnetic resonance imaging in patients with ossification of the posterior longitudinal ligament (OPLL) (n = 25) and patients with cervical spondylotic myelopathy (CSM) (n = 49). The relationships between the expansion ratio and the Japanese Orthopedic Association (JOA) score, JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), and postoperative laminae morphology were investigated.

    Results. In the OPLL group, the expansion ratio was significantly positively correlated with the postoperative JOA score (P = 0.025), recovery rate of the JOA score (P = 0.026), and postoperative change in lower extremity sensory function according to the JOA score (P = 0.0375); furthermore, patients whose JOACMEQ responses indicated positive outcomes for lower extremity function had a significantly larger expansion ratio than patients with negative results (P = 0.027). In the CSM group, the expansion ratio showed no correlation with the JOA and JOACMEQ scores. The expansion ratio was significantly positively correlated with the width between bilateral gutters in both CSM (P = 0.025) and OPLL (P = 0.0451). In the OPLL group, the expansion ratio in those with a gutter position of less than 0.8 was significantly smaller than that those with a gutter position of more than 0.8 (P = 0.0156). However, there was no correlation between the gutter position and the recovery rate of the JOA score.

    Conclusions. In OPLL, insufficient enlargement of the cross-sectional area of the dural sac at the symptomatic level leads to poor neurological improvements after laminoplasty.

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  • Makoto Takeuchi, Akihiro Nagamachi, Keisuke Adachi, Kazumasa Inoue, Ya ...
    Article ID: 2017-0071
    Published: 2018
    [Advance publication] Released: May 29, 2018
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    Introduction: A high-intensity zone (HIZ) in an intervertebral disc of the lumbar spine is a high-intensity signal located in the posterior annulus fibrosus on T2-weighted magnetic resonance imaging (MRI). There is limited information on the prevalence of HIZ in the lumbar spine according to age. The aim of this cross-sectional study was to investigate the prevalence of HIZ in the lumbar spine by age and the correlation between HIZ and other degenerative findings, such as disc degeneration, disc bulging and herniation, and changes in adjacent vertebral endplates on lumbar MRI.

    Methods and Methods: We retrospectively reviewed MRI studies of 305 patients (1525 discs) with low back pain, leg pain, or numbness. The prevalence of HIZ was calculated in 5 age groups (<20, 20–39, 40–59, 60–79, 80–91 years).

    Results: The number of patients in the 5 age groups was 19, 38, 69, 145, and 36, respectively. The prevalence of HIZ in the 5 age groups was 11.8%, 47.3%, 52.2%, 42.8%, and 50.0%, respectively. Disc degeneration was observed in 58.1% and 39.2% of discs with and without HIZ, respectively; disc bulging and herniation was observed in 63.9% and 41.1% and intensity changes at adjacent end plates in 11.6% and 10.0%, respectively.

    Conclusion: Prevalence of HIZ from the third decade of life onward was around 50%, with no significant change in prevalence beyond the age of 20 years. HIZ was correlated with disc degeneration, disc bulging, and disc herniation in patients with LBP, leg pain, or numbness.

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  • Koki Abe, Kazuhide Inage, Sumihisa Orita, Yoshihiro Sakuma, Hirohito K ...
    Article ID: 2017-0094
    Published: 2018
    [Advance publication] Released: May 29, 2018
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    Introduction: Thus far, few reports have described the time series histological variations in injured paravertebral muscle tissues for long durations, considering the type of pain.

    Purpose: To evaluate histological changes in injured paravertebral muscles and dominant nerves considering the type of pain.

    Methods: We used 59 eight-week-old male Sprague-Dawley rats. A 115-g weight was dropped from a height of 1 m on the right paravertebral muscle. Fluoro-Gold (FG), a sensory nerve tracer, was injected into this muscle. Hematoxylin and eosin (HE) staining and nerve growth factor (NGF) immunostaining of the muscle were performed for histological evaluation. L2 dorsal root ganglia (DRG) on both sides were resected, and immunohistochemical staining was performed for calcitonin gene-related peptide (CGRP, a pain-related neuropeptide) and for activating transcription factor 3 (ATF3, a neuron injury marker). Each examination was performed at 3 days, 1–3 weeks, and 6 weeks after injury.

    Results: HE staining of the paravertebral muscle indicated infiltration of inflammatory cells and the presence of granulation tissue in the injured part on the ipsilateral side at 3 days and 1 week after the injury. Fibroblasts and adipocytes were present at 2–3 weeks. At 6 weeks, the injured tissue was almost completely repaired. NGF was detected at 2–3 weeks post injury and appeared to colocalize with fibroblasts, but was not observed at 6 weeks post injury. The percentage of cells double-labeled with FG and CGRP in FG-positive cells of the primary muscle was significantly higher in the injured side at 3 days and 1–3 weeks post injury (P < 0.05). However, at 6 weeks, no significant difference was observed. No significant expression of ATF3 was observed.

    Conclusions: These results suggest that sensitization of the dominant nerve in the DRG, in which NGF may play an important role, can protract pain in injured muscles.

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  • Yoichiro Hatta, Hitoshi Tonomura, Masateru Nagae, Ryota Takatori, Yasu ...
    Article ID: 2017-0097
    Published: 2018
    [Advance publication] Released: May 29, 2018
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    Introduction. Favorable short-term outcomes have been reported following muscle-preserving interlaminar decompression (MILD), a less invasive decompression surgery for lumbar spinal canal stenosis (LSCS). However, there are no reports of mid- to long-term outcomes. The purpose of this study was to evaluate the clinical outcomes five or more years after treatment of LSCS with MILD.

    Methods. Subjects were 84 cases with LSCS (44 males; mean age, 68.7 years) examined five or more years after MILD. All patients had leg pain symptoms, with claudication and/or radicular pain. The patients were divided into three groups depending on the spinal deformity: 44 cases were without deformity (N group); 20 had degenerative spondylolisthesis (DS group); and 20 had degenerative scoliosis (DLS group). The clinical evaluation was performed using Japanese Orthopedic Association (JOA) scores, and revision surgeries were examined. Changes in lumbar alignment and stability were evaluated using plain radiographs.

    Results. The overall JOA score recovery rate was 65.5% at final follow-up. The recovery rate was 69.5% in the N group, 65.2% in the DS group, and 54.0% in the DLS group, with the rate of the DLS group being significantly lower. There were 16 revision surgery cases (19.0%): seven in the N group (15.9%), three in the DS group (15.0%) and six in the DLS group (30.0%). There were no significant differences between pre- and postoperative total lumbar alignment or dynamic intervertebral angle in any of the groups, slip percentage in the DS group, or Cobb angle in the DLS group.

    Conclusions. The mid-term clinical results of MILD were satisfactory, including in cases with deformity, and there was no major impact on radiologic lumbar alignment or stability. The clinical outcomes of cases with degenerative scoliosis were significantly less favorable and the revision rate was high. This should be taken into consideration when deciding on the surgical procedure.

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  • Masatoshi Morimoto, Toshinori Sakai, Tsuyoshi Goto, Kosuke Sugiura, Hi ...
    Article ID: 2017-0099
    Published: 2018
    [Advance publication] Released: May 29, 2018
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    Introduction: Recent advances in diagnostic imaging, such as computed tomography (CT) and magnetic resonance imaging (MRI), have allowed early diagnosis of lumbar spondylolysis (LS). However, few outpatient clinics are equipped with such imaging apparatuses and must rely on plain radiographs for the diagnosis of LS. The aim of this retrospective study was to identify how accurately fracture lines can be detected on plain radiographs in patients with LS.

    Methods: Patients with a diagnosis of LS were staged as early, progressive, or terminal. We evaluated whether fracture lines could be detected on plain radiographs and compared the detection rates under the following conditions: two directions including anteroposterior and lateral views (2 views), four directions including both oblique views (4 views), four directions including dynamic lateral views (4-D views), and all six directions (6 views).

    Results: In early LS, the fracture line detection rate was 11.4% using 2 views, 20.5% using 4 views and 4-D views, and 22.7% using 6 views. In progressive LS, the fracture line detection rate was 54.2% using 2 views, 70.8% using 4-D views, 75.0% using 4 views, and 79.2% using 6 views. The respective detection rates for terminal LS were 85.0%, 100%, 100%, and 100%.

    Conclusions: Although terminal LS was diagnosed accurately on plain radiographs in all patients, the detection rates were only 22.7% and 79.2% in patients with early and progressive LS, respectively. These results suggest that plain radiographic films can no longer be considered adequate for early and accurate diagnosis of LS. Advanced imaging procedures, such as MRI in the early diagnosis or CT for persistent cases, are recommended to obtain an accurate diagnosis of early stage LS in pediatric patients requiring conservative treatment to achieve bony healing.

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  • Laxmikant Dagdia, Terufumi Kokabu, Manabu Ito
    Article ID: 2017-0100
    Published: 2018
    [Advance publication] Released: May 29, 2018
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    Although adult spinal deformity (ASD) has become a global health problem, the classification system and optimal surgical treatment for ASD is yet to be standardized worldwide. A significant part of the population, as high as 10%, in industrialized societies will be aged above 65 years within the next 10 years. Herein, a systematic review of the scientific literature related to the classification and treatment of ASD was conducted wherein historical to the most recent classifications of ASD were reviewed. By discussing the benefits and limitations of the previous classification systems and considering the factors affecting the clinical outcomes of surgical treatment of ASD, this article would like to propose future directions for the development of a new classification system for ASD.

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  • Hirosuke Nishimura, Shinjiro Fukami, Kenji Endo, Hidekazu Suzuki, Yasu ...
    Article ID: 2018-0005
    Published: 2018
    [Advance publication] Released: May 29, 2018
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    This was a study of the case of a 60-year-old woman who presented with a six-month history of headache and numbness radiating to the right arm. MRI revealed a fusiform intramedullary spinal tumor spanning C2 to C5 at the hospital where she first presented. As her right upper limb weakness had presented gradually, she visited our hospital after one and a half years. Neurological examination revealed muscle weakness in the right deltoid, but no sensory disturbance.

    The patient underwent a C2-C6 total laminectomy and posterior midline myelotomy from the posterior median fissure of the spinal cord. The intraoperative histological diagnosis was glioma.

    Pathological findings in low magnification demonstrated clusters of small uniform nuclei embedded in a dense and fibrillary matrix in hematoxylin-eosin staining (H.E.). On immunohistochemical staining, the tumor cells were weakly positive for glial fibrillary acidic protein (GFAP), but negative for the epithelial membrane antigen (EMA). The histopathological findings were consistent with the diagnosis of a subependymoma. However, the MIB-1 labeling index was of moderately high level up to approximately 8%.

    In this case, we performed total resection because the tumor had rapidly increased in size and was of atypical form in histological findings.

    It should be minded that some of subependymomas have a possibility of rapidly increasing in size with progressing neurological deficits.

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  • Hiroaki Manabe, Toshinori Sakai, Fumitake Tezuka, Kazuta Yamashita, Yo ...
    Article ID: 2018-0015
    Published: 2018
    [Advance publication] Released: May 29, 2018
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    Introduction: C4 radiculopathy due to cervical spondylosis has rarely been reported as a cause of hemidiaphragmatic paralysis.

    Case Report: A 70-year-old man presented with hemidiaphragmatic paralysis due to right C3-C4 foraminal stenosis. The diagnosis was made preoperatively from findings on plain chest radiographs, respiratory function tests, and electrophysiologic tests. All the patient's test results and symptoms improved immediately after surgical treatment for cervical spondylosis.

    Conclusions: Although it may be difficult to make a correct diagnosis based only on radiological findings at the cervical spine, we should be aware of the existence of this entity and pay close attention to chest radiographs.

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  • Shigeru Hirabayashi, Tomoaki Kitagawa, Iwao Yamamoto, Kazuaki Yamada, ...
    Article ID: 2018-0016
    Published: 2018
    [Advance publication] Released: May 29, 2018
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    Postoperative C5 palsy (C5 palsy) is defined as de novo or aggravating muscle weakness mainly at the C5 region with slight or no sensory disturbance after cervical spine surgery. The features of C5 palsy are as follows: 1) one-half of patients are accompanied by sensory disturbance or intolerable pain at the C5 region; 2) 92% of patients have hemilateral palsy; 3) almost all palsy occurs within a week after surgery; 4) the incidence is almost the same between the anterior and posterior approaches to the cervical spine; 5) the prognosis is relatively good even in patients with severe muscle weakness. Even now, the precise causes of C5 palsy have not yet been revealed. From the viewpoint of the kinds of nerve tissue involved, the uncertain causes of C5 palsy are divided into two theories: 1) the segmental spinal cord disorder theory and 2) the nerve root injury theory. In the former, the segmental spinal cord, particularly the anterior horn cells, is thought to be chemically damaged because of preoperative ischemia and/or the aggression of reactive oxygen during postoperative reperfusion. By contrast, in the latter, the anterior rootlet and/or nerve root are believed to be mechanically damaged because of compression force and/or distraction force. In this theory, the features of C5 palsy can be well explained from anatomical viewpoints. Additionally, various countermeasures have been proposed, such as the intermittent relaxation of the tension of the hooks to the multifidus muscles during surgery; prophylactic foraminotomy to decompress C5 nerve root; prevention of excessive posterior shift of the spinal cord, which may cause the tethering effect of the nerve root; and prevention of excessive postoperative lordotic alignment of the cervical spine. These countermeasures have been proved effective, and may support the nerve root injury theory as the main conjectured theory on the causes of C5 palsy.

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  • Ryunosuke Fukushi, Satoshi Kawaguchi, Goichi Watanabe, Keiko Horigome, ...
    Article ID: 2018-0017
    Published: 2018
    [Advance publication] Released: May 29, 2018
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    Introduction: Vertebral fractures associated with ankylosing spinal disorders pose significant diagnostic and therapeutic challenges. Notably, the ankylosed spine remains in ankylosis after fracture treatment, and the underlying susceptibility to further fractures still remains. Nevertheless, information is scarce in the literature concerning patients with ankylosing spinal disorders who have multiple episodes of vertebral fractures.

    Case report: Case 1 involves an 83-year-old male patient with diffuse idiopathic skeletal hyperostosis (ankylosis from C2 to L4) who had three episodes of vertebral fractures. The first episode involved a C5–C6 extension-type fracture, which was treated with posterior segmental screw instrumentation. Five years later, the patient sustained a three-column fracture at the L1 vertebra following another fall. The fracture was managed with percutaneous segmental screw instrumentation. One year and two months postoperatively, the patient fell again and had a refracture of the healed L1 fracture. The patient was treated with a hard brace, and the fracture healed. Case 2 involves a 76-year-old female patient with ankylosing spondylitis (ankylosis from C7 to L2) who had two episodes. At the first episode, she suffered paraplegia due to a T8 vertebra fracture. The patient was treated with laminectomy and posterior segmental screw instrumentation. The patient recovered well and had all the hardware removed at 10 months postoperatively. Five years later, she had another fall and suffered a three-column fracture at L1. The patient underwent percutaneous segmental screw instrumentation. The patient required revision surgery with L1 laminectomy and L1 right pediclectomy for persistent right inguinal pain. At one-year follow-up, the patient recovered well, and the fracture healed.

    Conclusion: The abovementioned cases show that an age older than 75 years and a long spinal ankylosis from the cervical spine to the lumbar spine may serve as risk factors for the repetition of vertebral fractures associated with ankylosed spinal disorders.

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  • Norito Hayashi, Hideaki Iba, Kazuhiro Ohnaru, Kazuo Nakanishi, Toru Ha ...
    Article ID: 2017-0062
    Published: 2018
    [Advance publication] Released: April 27, 2018
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    Introduction. There are patients with lumbar disc herniation (LDH) having contralateral sciatic symptoms although the mechanisms of this clinical feature are still not well understood. The purpose of this study was to investigate these mechanisms by microendoscopic findings.

    Methods. Patients were performed microendoscopic surgery using over-the-top approach (ME-OTT), with laminoplasty, extirpation of herniation, and observation of the contralateral nerve root. The over-the-top approach was applied through the same incision from the herniation side. Clinical results were assessed according to the clinical scoring system established by the Japanese Orthopedic Association (JOA) score.

    Results. This study consisted of five patients, with the average age of 55.6 years old. The mean preoperative JOA score was 13 points. Three cases were Grade II and two were Grade III degrees of disc herniation. Levels of herniation were one at L3–4 and four at L4–5. Remission of sciatic symptoms was obtained in all cases after surgery. The average and percent improvements (%IP) of JOA scores at 2 months after surgery were 27.8 points and 92%, respectively. By the approach from the herniation side using ME-OTT, image around the contralateral nerve root was obtained without radical intervention. By ME-OTT, redness of the nerve root and fibrosis around the symptomatic nerve root were identified, whereas inflammatory changes were not apparent on the ipsilateral nerve root.

    Conclusions. Operative treatment of LDH with contralateral symptoms by ME-OTT was a useful procedure for decompression and observation of the affected nerve root. Asymptomatic disc herniation, "silent disc herniation," was considered at the herniation side since there were less inflammatory changes around the ipsilateral nerve root. In contrast, compression of dura toward the opposite side by disc herniation could have led to mechanical stress against the contralateral nerve root and triggered inflammation at lateral recess, resulting in radicular pain.

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  • Gaurav Raj Dhakal, Santosh Paudel, Siddharth Dhungana, Ganesh Gurung, ...
    Article ID: 2017-0087
    Published: 2018
    [Advance publication] Released: April 27, 2018
    JOURNALS FREE ACCESS ADVANCE PUBLICATION

    Background: Outcome of spine injury treated in resource constrained regions may not be the same as in developed nations. The aim of the present study was to study the epidemiological characteristics, delay, complications, and outcome of surgically treated dorsal and lumbar trauma.

    Methods: Retrospective study of dorsal and lumbar spine injury patients treated between December 2015 and August 2017. Patients were segregated into four groups based on the timing of surgery: 0 ̶ 2 days, 3 ̶ 7 days, 8 ̶ 30 days, and more than 31 days. Only one operating room twice a week was allotted to spine surgery, and spine had to compete with orthopedic and surgical trauma for admission and surgery.

    Results: Ninety-one patients (male 61) with mean age 33 years were operated for dorsal and lumbar spine injuries. 84% of the total patients sustained a fall, and 86.8% were from the periphery. Though 69.2% presented within 2 days, only 4.4% were operated within 2 days. Majority of the delay was due to unavailability of the operating room followed by financial constraints. Twenty-seven patients had complete deficit, 32 incomplete deficit, and 32 normal neurology. Four patients operated within 2 days improved their neurology, 7 incomplete deficit patients in 3 ̶ 7 days group improved, 6 in 8 ̶ 30 days group improved, whereas no patient in more than 31 days group improved. Overall 53.1% of neurologically incomplete deficit patients improved if operated within 30 days. No neurological improvement was seen in the 27 complete deficit patients. Wound infection, pulmonary contusion, and deep vein thrombosis were seen in 3 patients.

    Conclusion: As expected 95.6% of our patients were treated more than 3 days after injury and 60% more than a week later, which may not be acceptable in advanced countries. Despite the delay, 53.1% had an improvement in neurology when operated within 30 days. Hence, surgery still holds the hope of neurological recovery and quicker rehabilitation.

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  • Narihito Nagoshi, Ken Ishii, Kaori Kameyama, Osahiko Tsuji, Eijiro Oka ...
    Article ID: 2017-0088
    Published: 2018
    [Advance publication] Released: April 27, 2018
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    Introduction. Intramedullary lesions and tumors are generally accessed by a posterior approach. However, if the lesion is located on the ventral side of the spinal cord, a posterior resection with myelotomy poses technical difficulties. We report two cases of complete resection of a cervical ventral intramedullary cavernous hemangioma using an anterior approach.

    Case reports. Two cases of intramedullary cavernous hemangioma located on the ventral side of the spinal cord were successfully treated by total resection with anterior cervical corpectomy followed by anterior spinal fusion with an autologous bone strut from the iliac crest. In both cases, the postoperative course was uneventful, and there was no neurological deficit. Bony fusion was achieved, and there was no recurrence or complication during a follow-up period of at least two years.

    Conclusions. Here, we describe an anterior approach for total resection of cavernous hemangiomas on the ventral side of the cervical spinal cord. Outcomes were stable two years after the operations. Although the method should be assessed with more patients and a longer follow-up time, this anterior approach may be useful for the radical resection of a vascular malformation or tumor.

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  • Kazunari Takeuchi, Toru Yokoyama, Takuya Numasawa, Kan-ichiro Wada, Ta ...
    Article ID: 2017-0090
    Published: 2018
    [Advance publication] Released: April 27, 2018
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    Introduction. Difficulties with neck mobility often interfere with patients´ activities of daily living (ADL) after cervical posterior spine surgery. The range of motion of the cervical spine decreases markedly after multilevel cervical posterior decompression and fusion (PDF). However, details regarding the limitations of cervical spine function due to postoperative reduced neck mobility after multilevel PDF are as yet unclarified. The present study aimed to clarify the quality of life and its related factors after PDF, and the optimal fixed neck position in multilevel PDF that minimizes the limitations of ADL accompanying markedly reduced postoperative neck mobility.

    Methods. Limitations of ADL involving neck extension, rotation, and flexion were investigated in 32 consecutive patients who underwent C2-T1 PDF using the responses to the cervical spine function domain of the Japanese Orthopedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ). The EuroQol 5 Dimension, Japanese Orthopedic Association score, and five domains of the JOACMEQ were also investigated. We investigated the risk factors regarding the fixed neck position in PDF for the impossibility to perform ADL involving each of three movements using cut-off values obtained from receiver-operating characteristic curves.

    Results. Postoperative comprehensive quality of life was significantly related to neurological improvements and to poor outcomes of cervical spine function after PDF. The significant risk factors for impossibility to perform ADL involving neck rotation were a C2-C7 lordotic angle ≥ 6° (P = 0.0057) or a proportion coefficient of C2-T1 tilt angle/C2-C7 lordotic angle ≤ 1.8 (P = 0.0024). There were no significant risk factors for impossibility to perform ADL involving neck extension or flexion.

    Conclusions. The optimal fixed neck position in C2-T1 PDF to reduce postoperative limitations of ADL involving neck mobility is a C2-C7 lordotic angle of less than 6°, or a C2-T1 tilt angle (°) of greater than 1.8 × the C2-C7 lordotic angle (°).

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  • Shoichiro Takei, Masayuki Miyagi, Wataru Saito, Takayuki Imura, Gen In ...
    Article ID: 2017-0093
    Published: 2018
    [Advance publication] Released: April 27, 2018
    JOURNALS FREE ACCESS ADVANCE PUBLICATION

    Introduction: Patients with spinal muscular atrophy (SMA) usually have progressive scoliosis. Although fusion of the sacrum or pelvis has been recommended for correcting pelvic obliquity (PO), the procedure is invasive. This study determined as to whether performing instrumentation to the fifth lumbar vertebra (L5) is safe and effective for scoliosis in patients with SMA.

    Methods: Twelve patients with SMA underwent posterior spinal fusion and stopping instrumentation at the L5 level. We evaluated age at surgery, the duration of surgery, blood loss, complications, preoperative and postoperative Cobb angles, and PO.

    Results: The mean age at surgery was 11.4 years; the mean duration of surgery was 319 minutes, and the mean blood loss was 1170 mL. The Cobb angle improved from 97.3° to 39.1° at 1 month postoperatively (correction rate, 60.9%) and to 42.3° at the final follow-up. PO was corrected from 27.8° to 13.1° at 1 month postoperatively (correction rate, 51.7%) and to 19.8° at the final follow-up. No complications were reported. All patients showed improvement in low back pain, with reduced difficulty while sitting. However, >10% correction loss of PO was observed in 6 patients with high preoperative PO.

    Conclusions: The correction rate of scoliosis in SMA patients with posterior spinal fusion and instrumentation to the L5 level was acceptable, and no complications occurred. Scoliosis associated with SMA was more rigid and severer than scoliosis associated with Duchenne muscular dystrophy. Correction rates of the Cobb angle and PO in SMA patients with instrumentation to L5 were similar to those in SMA patients with instrumentation to the sacrum or pelvis. Correction loss of PO was greater in patients with high preoperative PO than in those with low preoperative PO. Instrumentation and fusion to L5 for scoliosis in patients with SMA seems safe and effective, except in cases of high preoperative PO.

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  • Ivan Sekiguchi, Naoki Takeda, Naoki Ishida
    Article ID: 2018-0002
    Published: 2018
    [Advance publication] Released: April 27, 2018
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    Introduction. In an attempt to increase anchoring strength of posterior instrumentation in spine with compromised bone quality, we introduced diagonal trajectory pedicle screwing (hooking screws) that do not rely on screw thread purchase in bone but rather hook onto the strong posterior elements of vertebrae from inside the bone.

    Methods. Between November 2016 and July 2017 we treated eight patients, mean age 80 years old (75–86 years old) with compromised bone quality for spinal instability. The diagnosis was osteoporotic fracture nonunion in three, ankylosed spine fracture in three, pyogenic spondylitis in two cases. All spines were percutaneously instrumented. Groove-entry technique was used for down-going thoracic screws. No additional hooks, cables, or any other augmentation was used. All patients were mobilized on post-operative day 1.

    Results. 84 screws were inserted overall. Groove-entry technique was used for 42 screws insertion. On average, 5.3 spinal segments were fixed per case. Mean operation time was 252 min (46 min per one spinal segment). Mean intraoperative bleeding was 112 ml per case (21 ml per one fixed spinal segment). All cases achieved bony union of the fracture site or across the destroyed intervertebral disk. Mean time to union was 4 months postop (3–7 months). All patients were ambulatory at the time of discharge. No nerve injury, no skin irritation caused by implants, no screw loosening, no screw pullout, no loss of correction, and no junctional kyphosis were noted in this series.

    Conclusion. Diagonal screw instrumentation (our hooking screws and groove-entry technique) appears to provide sufficient anchoring strength while being minimally invasive and possibly helpful in prevention of junctional kyphosis.

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  • Yoshihiro Matsumoto, Kenichi Kawaguchi, Jun-ichi Fukushi, Makoto Endo, ...
    Article ID: 2018-0004
    Published: 2018
    [Advance publication] Released: April 27, 2018
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    Purpose: To investigate the clinical outcome and prognostic factors of malignant spinal dumbbell tumors (m-SDTs).

    Methods: We retrospectively reviewed the clinical outcome of 22 consecutive cases of m-SDTs and analyzed the prognostic factors associated with worse outcome.

    Results: Nineteen of the 22 cases were managed with surgery (86%), and gross total resection (GTR) was achieved in four cases (21%). The duration of overall survival (OS) ranged from 3 to 140 months, with a median survival time of 15.3 months. The 5 year OS rate was 55.6%. In multivariate analysis, histological subtype (high-grade malignant peripheral nerve sheath tumor) (hazard ratio [HR] 14.9, p = 0.0191), GTR (HR 0.07, p = 0.0343), and presence of local recurrences (HR 11.2, p = 0.0479) were significant and independent predictors of OS.

    Conclusions: On the basis of clinical data, we propose that GTR and prevention of local recurrence may improve the clinical outcome of m-SDTs.

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  • Tatsuto Takeuchi, Keiichi Shigenobu
    Article ID: 2018-0010
    Published: 2018
    [Advance publication] Released: April 27, 2018
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    Introduction: Spinal subdural abscess (SSA) or empyema is a rare pathology and its exact incidence is unknown. Staphylococcus aureus (S aureus) is the most frequently responsible organism. The patients with SSA may have one or more predisposing immunosuppressive conditions. However, here we report a rare case of SSA following food intoxication without any significant comorbidities.

    Case report: A 42-year-old healthy man presenting with fever, severe low back pain (LBP), and trunk motion restriction was transferred to our hospital. He had been treated for an unknown fever after food intoxication in another hospital. Eighteen days earlier, he and his colleagues together ate raw horse meat and briefly boiled chicken breast. They all had food intoxication on the following day. Subsequently, our patient began to have a high fever and severe LBP. Laboratory data showed leukocytosis of 16,000/mm3. Also, the C-reactive protein was elevated to 26 mg/dL. The blood culture result was consistent with S aureus. Magnetic resonance imaging (MRI) showed focal epidural fluid collection that appeared contiguous with the subdural fluid collection through a dural defect in the axial plane on T2-weighted (T2W) images. An emergent surgery was performed. Frank pus was expressed from the epidural space as well as from the subdural space through the defect. The pus later grew S aureus. The patient was started on antibiotic therapy postoperatively. The patient completely recovered 1 month after surgery.

    Conclusion: SSA following food intoxication is a very rare case. SSA can be identified with a small dural defect and the intrathecal fluid collection compressing the cauda equina in the axial plane on T2W magnetic resonance images. Having suspicion of epidural abscess and likewise subdural abscess and making an early diagnosis using MRI and an emergent surgery are important when the clinician notices a febrile patient with severe LBP and trunk motion stiffness.

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  • Hiroyuki Takashima, Tsuneo Takebayashi, Mitsunori Yoshimoto, Maki Onod ...
    Article ID: 2017-0069
    Published: 2018
    [Advance publication] Released: April 07, 2018
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    Introduction: Gender differences may play a role in the pathogenesis of lumbar spinal stenosis. However, few reports that discuss the effects of gender differences in ligamentum flavum (LF) hypertrophy have been published, and no study has investigated the relationship between LF thickness and the quantitative value of intervertebral disc (IVD) degeneration. This study aimed to investigate the impact of gender on the pathomechanisms underlying LF hypertrophy, focusing on the relationship among LF thickness, IVD degeneration, and age.

    Methods: The subjects include 100 patients with low back pain and leg numbness, tingling, or pain. We measured LF thickness and the T2 values of IVDs using MR imaging and analyzed the relationship among LF thickness, T2 values of IVDs, and age. The interclass correlation coefficient (ICC) was calculated as the inter-rater reliability between the LF thickness values measured by two investigators.

    Results: ICC was calculated for the two measurements of LF thickness (r = 0.923, 95% CI: 0.907–0.936). No statistically significant difference in the T2 values of IVDs was observed between females and males from L2/3 to L5/S. There were significantly negative linear correlations between LF thickness and the T2 values of IVDs at all levels, but this correlation was not observed in females at L4/5. There were significantly negative linear correlations between age and the T2 values of IVDs from L2/3 to L5/S for all patients, females, and males (r = 0.422–0.756). In addition, there were significantly positive linear correlations between age and LF thickness from L2/3 to L4/5 for all patients (r = 0.329–0.361) and females (r = 0.411–0.481). Correlations were not observed for males at all levels or for all patients at L5/S.

    Conclusions: The relationships identified among LF thickness, age, and IVD degeneration suggest that gender differences play a role in the pathogenesis of LF hypertrophy.

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  • Mitsuyoshi Matsumoto, Masayuki Miyagi, Wataru Saito, Takayuki Imura, G ...
    Article ID: 2017-0075
    Published: 2018
    [Advance publication] Released: April 07, 2018
    JOURNALS FREE ACCESS ADVANCE PUBLICATION

    Purpose: Patients with neuromuscular disorders sometimes show progressive spinal scoliosis. The surgery for neuromuscular scoliosis (NMS) has high rates of complications. In this study, we elucidated the perioperative complications in patients with NMS.

    Methods: We included 83 patients with NMS (58 boys and 25 girls; 61 with muscular dystrophy, 18 with spinal muscular atrophy, and 4 others) who had undergone posterior fusion surgery for scoliosis. We evaluated the perioperative complications (within 3 months), age at time of surgery, operative time, blood loss, preoperative %VC and FEV1.0 (%) for pulmonary function, and preoperative ejection fraction (EF) for cardiac function.

    Results: There were 5 (6%) major complications, including pneumonia and a cardiovascular complication requiring intensive care unit (ICU) care, and 15 (18%) minor complications including viral enteritis and a urinary tract infection. Overall, there were 20 (24%) complications. Three of the 5 major complications were pulmonary. The mean age at the time of surgery was 13.7 y, operative time was 304 min, and blood loss was 1530 ml. The mean preoperative %VC was 41%, FEV1.0 was 91%, and EF was 60%. When we separated the patients into a group with major complications (n = 5) and a group without major complications (n = 78), the preoperative %VC in the group with major complications (23%) was significantly lower than that in the group without (42%) (p < 0.05). However, operative time, blood loss, preoperative FEV1.0 (%) and EF between the two groups were not significantly different (p > 0.05).

    Conclusion: Compared with the previous findings of the perioperative complication rate (45%–74%) for NMS, the complication rate was remarkably low in this case series. Because of advances in medical skills, including anesthesia and surgical instruments, surgery for NMS appears to be safe. However, patients with NMS with complications demonstrated severe restrictive ventilatory impairment preoperatively. Therefore, we should be vigilant for perioperative pulmonary complications especially in patients with NMS and preoperative severe restrictive ventilatory impairment.

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  • Tatsuya Yasuda, Tomohiko Hasegawa, Yu Yamato, Daisuke Togawa, Sho Koba ...
    Article ID: 2017-0081
    Published: 2018
    [Advance publication] Released: April 07, 2018
    JOURNALS FREE ACCESS ADVANCE PUBLICATION

    Object

    Correction of lumbar lordosis is the primary goal of surgical treatment of adult spinal deformity. However, only limited research has evaluated the effects of this correction on the adaptive curvature of the thoracic spine. The purpose of this study is to evaluate the change in thoracic curvature after corrective surgery to restore lumbar lordosis in patients with adult spinal deformity.

    Methods

    We completed a retrospective analysis of the radiological data of 65 patients, ≥50 years old, who underwent corrective surgery of lumbar spine lordosis from any level below T8 to the ilium. Patients with insufficient correction, defined by a pelvic incidence minus lumbar lordosis angle (PI-LL) > 10°, were excluded, with the data of 43 patients included in the analysis. The following radiological measures of spinal alignment were measured at three time points, preoperatively, on the first day of standing postoperatively and at 2 years post-surgery: sagittal vertical axis (SVA), lumbar lordosis (LL), thoracic kyphosis (TK), pelvic tilt (PT), and PI-LL.

    Results

    Postoperative change in TK was correlated to preoperative TK and age. The increase in TK was larger for patients <75 years of age, increasing from 23.1° to 38.0° after surgery and to 46.7° at 2-years postoperatively. In contrast, for patients >75 years, TK remained largely unchanged at 37.8° just after surgery but increased substantively to 50.1° at the 2-year follow-up. The postoperative change in TK immediately after surgery was determined using equation "predict change in TK = −0.21 × age − 0.6 × preoperative TK + 41.8" by multiple regression analysis.

    Conclusion

    Reciprocal change in TK after lumbar spine correction is correlated to preoperative TK and age.

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  • Manabu Mukai, Masayuki Miyagi, Tomohisa Koyama, Takayuki Imura, Kuniak ...
    Article ID: 2017-0085
    Published: 2018
    [Advance publication] Released: April 07, 2018
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    Introduction: Spontaneous spinal epidural hematomas (SSEHs) are rare in childhood, especially in infants.

    Case report: We present the case of a 17-month-old-boy with trisomy 21 and a large SSEH. He was hospitalized for acute onset paraplegia after 6 days of irritability. Nine days after symptom onset, magnetic resonance imaging (MRI) of the spine revealed an extensive epidural hematoma between C7 and T5 causing severe spinal cord compression. After a coagulation disorder was ruled out (12 days after onset), he underwent emergency hemilaminectomy with evacuation of the hematoma. His neurologic impairment gradually improved, and 4 months after surgery he was back to his neurologic baseline. At 18 months after surgery, he was walking independently, although he had some developmental disabilities due to trisomy 21.

    Conclusion: Only 20 cases of SSEH in infancy have been previously reported, and this is the first report of SSEH in an infant with developmental disabilities. Because of the non-specific symptoms and difficulty obtaining MRIs in infants, particularly in those with developmental disabilities, the diagnosis and treatment of SSEH may be delayed. However, early diagnosis with MRI and early evacuation of SSEH in patients with severe neurological impairments is important for good outcomes. Attention must be paid to postoperative spinal deformity in infants.

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  • Sean M. Rider, Shuichi Mizuno, James D. Kang
    Article ID: 2017-0095
    Published: 2018
    [Advance publication] Released: April 07, 2018
    JOURNALS FREE ACCESS ADVANCE PUBLICATION

    Intervertebral disc degeneration is a well-known cause of disability, the result of which includes neck and back pain with associated mobility limitations. The purpose of this article is to provide an overview of the known molecular mechanisms through which intervertebral disc degeneration occurs as a result of complex interactions of exogenous and endogenous stressors. This review will focus on some of the identified molecular changes leading to the deterioration of the extracellular matrix of both the annulus fibrosus and nucleus pulposus. In addition, we will provide a summation of our current knowledge supporting the role of associated DNA and intracellular damage, cellular senescence's catabolic effects, oxidative stress, and the cell's inappropriate response to damage in contributing to intervertebral disc degeneration. Our current understanding of the molecular mechanisms through which intervertebral disc degeneration occurs provides us with abundant insight into how physical and chemical changes exacerbate the degenerative process of the entire spine. Furthermore, we will describe some of the related molecular targets and therapies that may contribute to intervertebral repair and regeneration.

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  • Kotaro Satake, Tokumi Kanemura, Hiroaki Nakashima, Yoshimoto Ishikawa, ...
    Article ID: 2017-0096
    Published: 2018
    [Advance publication] Released: April 07, 2018
    JOURNALS FREE ACCESS ADVANCE PUBLICATION

    Purpose

    This retrospective study was performed to evaluate the clinical influence of - and to identify the risk factors for nonunion of transpsoas lateral lumbar interbody fusion (LLIF) with use of allograft.

    Methods

    Sixty-three patients who underwent transpsoas LLIF (69.8 ± 8.9 years, 21 males and 42 females, 125 segments) were followed for a minimum 2 years postoperatively. For all LLIF segments, polyetheretherketone (PEEK) cages packed with allogenic bone were applied with supplemental bilateral pedicle screws (PSs). Bone bridge formation was evaluated by computed tomography (CT) 2 years postoperative, and a segment without any bridge formation was determined to be a nonunion. Sixty-one participants (96.8%) were classified into two groups for clinical evacuation: Group N that contained one or more nonunion segments and Group F that contained no nonunion segment. Visual analogue scales (VAS) scores and the effective rates of the five domains of the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) were compared between Groups N and F. The risk factors for nonunion were determined by univariate and multivariate analyses.

    Results

    Twenty segments (16%) were diagnosed as nonunion. There were no significant differences in all VAS scores, and the ratio of effective cases in all domains of JOABPEQ between Group N (n = 14) and F (n = 47). Multivariate analysis identified percutaneous PS (PPS) usage (odds ratio [OR]: 3.14, 95% confidence interval: 1.13–8.68, p = 0.028) as a positive risk factor for nonunion.

    Conclusions

    We should be aware of the higher nonunion rate in the LLIF segments supplemented with PPS, though nonunion does not affect significantly clinical outcomes at 2 years postoperative.

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  • Hidekazu Suzuki, Kenji Endo, Yasunobu Sawaji, Yuji Matsuoka, Hirosuke ...
    Article ID: 2017-0074
    Published: 2018
    [Advance publication] Released: March 15, 2018
    JOURNALS FREE ACCESS ADVANCE PUBLICATION

    Background

    Most people in modern societies spend the majority of their time sitting. However, sagittal spinal alignment is usually analyzed in the standing position. For understanding the symptoms associated with postural changes, this alignment is better to be analyzed in various positions. The purpose of this study was to investigate lumbo-pelvic relationships between standing up and sitting (sit-to-stand) motion.

    Methods

    The study subjects were 25 healthy young adult volunteers without any spinal symptoms. The following parameters were measured, namely, intervertebral range of motion (IV ROM), lumbar lordotic angle (L1L5), sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI), on lateral whole-spine radiographs while sitting upright, sitting anterior flexed (anteflexed), standing anteflexed, and standing upright.

    Results

    The measurements of spinopelvic parameters during sit-to-stand motion (sitting upright, sitting anteflexed, standing anteflexed, standing upright, respectively) were as follows: L1L5 (7.9, −4.4, 3.1, 31.9) and PT (31.5, 26.5, 11.9, 7.7). Regarding IV ROM, the lumbar segmental ROM after seat-off was wider than before seat-off (sitting anteflexed). In particular, the L4-L5 segments had a wide ROM from standing anteflexed to standing upright.

    Conclusion

    The pelvis was retroverted in the sitting upright position and gradually anteverted during sit-to-stand motion. Lumbar lordosis decreased in the sitting upright position, temporarily decreased further (sitting anteflexed), and then increased in the standing position (standing anteflexed and standing upright). The mechanical loads on lumbosacral segments were greater after seat-off due to the reverse movement between upper lumbar and pelvic segments.

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