Publications by authors named "Kazuyoshi Kobayashi"

Article Synopsis
  • A study was conducted to explore the link between obesity and the progression of OPLL (heterotopic ossification of the posterior longitudinal ligament of the spine) in Asian patients, focusing on how fat-related biochemical signals, or adipokines, might impact this condition.
  • Researchers compared adipokine levels, including leptin and adiponectin, between patients with different degrees of OPLL severity and healthy controls to see if these factors correlate with disease progression.
  • Findings revealed that patients with more severe OPLL had a higher BMI, lower adiponectin/leptin ratios, and elevated osteocalcin, suggesting a potential relationship between obesity, adipokine dysregulation, and the severity of OPLL.*
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Background: Unstable femoral trochanteric fractures (FTFs), especially Arbeitsgemeinschaft für Osteosynthesefragen/ the Orthopedic Trauma Association (AO/OTA) 31-A2 fractures, which are multifragment fractures, occur in elderly individuals with osteoporosis and are associated with high mortality and complication rates due to prolonged immobilization. Longer nails (LNs) were developed to obtain superior fracture site stabilization in unstable FTFs. We hypothesized that the postoperative outcomes of elderly patients with unstable FTFs treated with LNs would be superior to those of patients treated with short nails (SNs), with fewer complications.

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Introduction: Femoral neck fracture (FNF) is among the most common and devastating injuries that orthopedic surgeons encounter. However, the incidence of FNF is lower in younger adults than in elderly individuals. In elderly FNF patients, early weight bearing (EWB) is preferred to prevent loss of function and decreased activity.

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Background: Cervicobrachial pain frequently affects the quality of life (QOL) of the general public and has a significant economic impact on the health care systems of various countries. There are a number of treatment options for this disease, including widely-used drug therapy, but the effectiveness of each option is indeterminate, and there have been no published cost-effectiveness analysis studies so far. This prospective observational study aimed to examine the cost-effectiveness of drug treatment for cervicobrachial symptoms.

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Study Design: Prospective multicenter study.

Objective: To investigate the validity of transcranial motor-evoked potentials (Tc-MEP) in thoracic spine surgery and evaluate the impact of specific factors associated with positive predictive value (PPV).

Methods: One thousand hundred and fifty-six cases of thoracic spine surgeries were examined by comparing patient backgrounds, disease type, preoperative motor status, and Tc-MEP alert timing.

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Article Synopsis
  • Ossification of the posterior longitudinal ligament of the spine (OPLL) is a disease that can cause serious neurological issues, and its causes are not fully understood, particularly in relation to type 2 diabetes and high body mass index (BMI).
  • A comprehensive meta-analysis involving 22,016 Japanese individuals identified 14 significant genetic markers linked to OPLL, with 8 being newly discovered, and further analyses pointed to specific genes associated with the disease.
  • The research revealed that increased BMI and high bone mineral density could have a causal relationship with OPLL, and different subtypes of the disease were identified, particularly highlighting a strong correlation between BMI and thoracic OPLL.
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Study Design: A retrospective comparative study of denosumab therapy adherence before and during the coronavirus disease 2019 (COVID-19) pandemic.

Purpose: To evaluate the effect of the COVID-19 pandemic on denosumab therapy adherence in Japan.

Overview Of Literature: Denosumab is a monoclonal antibody for osteoporosis treatment.

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Use of instrumentation has become widespread in spinal surgery due to intraoperative spinal cord monitoring, navigation, and improvement and development of implant materials. However, recent advances in spine surgery may have also led to an increase in medical costs. The purpose of this study is to investigate the trends of operative resource utilization and the costs of surgery for adolescent idiopathic scoliosis (AIS) over 15 years.

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Study Design: A prospective multicenter observational cohort study.

Objective: This study aimed to investigate the role of transcranial motor evoked potential (TcMEP) monitoring during traumatic spinal injury surgery, the timing of TcMEP alerts, and intervention strategies to avoid intraoperative neurological complications.

Summary Of Background Data: Intraoperative neuromonitoring, including TcMEP monitoring, is commonly used in high-risk spinal surgery to predict intraoperative spinal cord injury; however, little information is available on its use in traumatic spinal injury surgery.

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Background: Lumbar disc herniation (LDH) results in low back pain due to nerve root compression caused by nucleus pulposus degeneration. Chemonucleolysis of the nucleus pulposus by injection of condoliase is less invasive than surgery, but may cause disc degeneration. The purpose of the study was to examine outcomes of condoliase injection in patients in their teens and twenties using Pfirrmann criteria on MRI.

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Article Synopsis
  • A study was conducted to investigate the current trends of intraoperative spinal neuromonitoring (IONM) usage among spine surgeons in Japan, as there are no established guidelines for its implementation.
  • A survey sent to 186 expert spine surgeons revealed a high response rate of 72%, with most surgeons using IONM routinely, particularly the Br(E)-MsEP method.
  • Despite its importance, one-third of surgeons reported complications, such as bite injuries, and two-thirds did not have plans for responding to alarm signals during surgeries, indicating a need for better protocols and cost-benefit analyses.
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The diagnosis of pediatric spinal cord tumor is frequently delayed due to the presence of non-specific symptoms. We investigated the factors influencing the delay between the first symptom presentation and the diagnosis for pediatric spinal cord tumor. We retrospectively analyzed 31 patients of age <20 years (18 men, 13 women) who underwent surgery for spinal cord tumor at a single center during 1998-2018.

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Introduction: Intervertebral disk degeneration is a universal and natural process. However, no reports have summarized anatomical age-related intervertebral disk height and disk degenerative changes in the thoracolumbar spine or examined sex-specific differences. This study aimed to establish age-related changes and gender-specific differences of intervertebral disk height and disk degeneration of the thoracolumbar spine in a large cohort of relatively healthy subjects and also to evaluate the relationship between the degree of thoracolumbar disk height and disk degeneration.

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Background: Lumbar disc herniation (LDH) is a common cause of low back pain and is associated with degeneration of the nucleus pulposus causing nerve root compression. Chemonucleolysis of the nucleus pulposus with condoliase is a low-invasive treatment for LDH. The purpose of this study was to investigate changes in Pfirrmann criteria, which are used to evaluate disc degeneration, after injection of condoliase into a herniated intervertebral disc, and to identify factors associated with disc degeneration at 3 months post-injection.

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Introduction: Risk factors associated with subchondral insufficiency fracture (SIF) of the femoral head have not been established. The aim of the present study was to determine the incidence and risk factors for SIF of the femoral head following renal transplantation (RT).

Materials And Methods: We analyzed the cases of 681 RT patients (mean age at surgery: 49.

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Study Design: A prospective multicenter observational study.

Objective: The aim was to investigate the validity of transcranial motor-evoked potentials (Tc-MEP) in cervical spine surgery and identify factors associated with positive predictive value when Tc-MEP alerts are occurred.

Summary Of Background Data: The sensitivity and specificity of Tc-MEP for detecting motor paralysis are high; however, false-positives sometimes occur.

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Study Design: A prospective, multicenter study.

Objective: This study clarified the uses and limitations of transcranial motor-evoked potentials (Tc-MEPs) for nerve root monitoring during adult spinal deformity (ASD) surgeries.

Summary Of Background Data: Whether Tc-MEPs can detect nerve root injuries (NRIs) in ASD surgeries remains controversial.

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Background: Excess visceral fat can accumulate owing to lack of exercise. The relationship between metabolic syndrome (MetS) and spinal range of motion (ROM) is not clear. The purpose of this study was to investigate the relationship between MetS and spinal alignment and ROM.

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The purpose of this study is to examine trends in spine surgeries at ten facilities over 15 years, and to analyze relationships with the number of spine surgeons at these facilities. The subjects were patients who underwent spine surgery at the ten facilities from 2003 to 2017. Data were collected every year via a questionnaire designed to obtain clinicopathological and surgical information.

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Article Synopsis
  • This study investigated the positioning of the ureter in relation to the spine during surgical procedures, focusing on the potential for ureteral injury.
  • Researchers analyzed CT scans from 100 patients who underwent lateral lumbar interbody fusion (LLIF) to assess ureter position across different lumbar disk levels.
  • Results revealed that ureters were more commonly found in a high-risk area (C region) on the left side and at lower lumbar levels, especially in women, emphasizing the importance of preoperative imaging to prevent injuries.
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