Yoichi Aota

• MD
• Chief at Fureai Yokohama Hospital

Introduction: Patients with adult spinal deformity (ASD) develop compensatory mechanisms. The Cobb angle between T4 and T12 has been used as a standard to define thoracic kyphosis (TK) because radiological evaluation is difficult in upper thoracic region. The upper thoracic compensatory mechanism has not been sufficiently explored, and focal thorac...

Background Previous studies reported that spinal nerve edema on magnetic resonance myelography (MRM) and leg pain at rest were specifically observed in symptomatic lumbar foraminal stenosis patients. However, the correlation between leg pain at rest and spinal nerve edema in symptomatic foraminal stenosis has not been reported. Hypothesis The purp...

Background: Previous studies reported that spinal nerve edema on magnetic resonance myelography (MRM) and leg pain at rest were specifically observed in symptomatic lumbar foraminal stenosis patients. However, the correlation between leg pain at rest and spinal nerve edema in symptomatic foraminal stenosis has not been reported. Hypothesis: The pur...

Background data: Correlation between lumbar degenerative disease and degenerative disorders of the knee joint have often been reported, however, detailed research concerning lumbar degenerative spondylolisthesis (DS) who complicates osteoarthritis of the knee (KOA) are scarce. Methods: A total of 184 consecutive surgically treated DS patients we...

The purpose of this study was to investigate the clinical and radiological features of osteoporotic burst fractures affecting levels below the second lumbar (middle-low lumbar) vertebrae, and to clarify the appropriate surgical procedure to avoid postoperative complications. Thirty-eight consecutive patients (nine male, 29 female; mean age: 74.8 ye...

Background To our knowledge, no studies have reported the exact structural leg length discrepancies (LLDs) in patients with adolescent idiopathic scoliosis (AIS). Therefore, this study aimed to evaluate the differences between functional and structural LLDs and to examine the correlations between LLDs and spinopelvic parameters in patients with AIS...

Background Pediatric Langerhans cell histiocytosis (LCH) often results in vertebral compression fracture. However, few reports have reported vertebral remodeling during the course of LCH. We aimed to investigate the longitudinal reconstitution and transformation of the affected vertebrae and the adjacent structures in young children with spinal LCH...

Recent studies have shown an association between osteopenia and adolescent idiopathic scoliosis (AIS) and implied that osteopenia plays a causative role in AIS development. This study aimed to determine if minodronate (MIN) treatment could prevent curve progression by increasing bone mass in a thoracic restraint (TR) mouse model, which develops cau...

Experimental data set of body weights from 4 to 9 weeks of age, Cobb angle, serum bone marker levels, femoral bone mineral density (BMD), and histomorphometry of the cancellous bone of the thoracic vertebrae. (XLSX)

Introduction: To assess the bone fusion rates and clinical results of two surgical methods (pedicle screw claw-hook fixation and pedicle screw hook fixation) of lumbar spondylolysis repair. Methods: A multicenter database of surgical patients with lumbar spondylolysis was reviewed. All patients < 20 years old with a minimum of 6 months of follow-up...

Objective The superior cluneal nerve (SCN) may become entrapped where it pierces the thoracolumbar fascia over the iliac crest; this can cause low back pain (LBP) and referred pain radiating into the posterior thigh, calf, and occasionally the foot, producing the condition known as “pseudo-sciatica.” Because the SCN was thought to be a cutaneous br...

Introduction: This study aimed to assess treatment outcomes and caregivers' satisfaction regarding scoliosis surgery for handicapped children. Methods: Handicapped children are, by definition, noncommunicatory and/or nonambulatory. We recruited 26 handicapped children who were followed-up for >1 year after a scoliosis surgery. We recruited 40 patie...

Object Entrapment of the middle cluneal nerve (MCN) under the long posterior sacroiliac ligament (LPSL) is a possible, and underdiagnosed, cause of low-back and/or leg symptoms. To date, detailed anatomical studies of MCN entrapment are few. The purpose of this study was to ascertain, using cadavers, the relationship between the MCN and LPSL and to...

PurposeAdolescent idiopathic scoliosis (AIS) is a three-dimensional deformity with increased risk of osteopenia of unknown etiology. This study examined the dynamic histomorphometry of AIS patients to gain insight into the underlying pathogenesis of bone metabolism changes in AIS. Methods Bone histomorphometry of the spinous process of the 12th tho...

Aims: To determine the normal values and usefulness of the C1/4 space available for spinal cord (SAC) ratio and C1 inclination angle, which are new radiological parameters for assessing atlantoaxial instability in children with Down syndrome. Patients and methods: We recruited 272 children with Down syndrome (including 14 who underwent surgical...

Background: Recently, corrective fusion surgery for patients with adult spinal deformity (ASD) has become common in Japan. This study aimed to clarify the status of surgeries for ASD in Japan, focusing on perioperative complications. A nationwide multicenter survey gathering information on surgically treated ASD patients was conducted by the commi...

Although laminar screw fixation is often used at the C2 and C7 levels, only few previous case reports have presented the use of laminar screws at the C3-C6 levels. Here, we report a novel fixation method involving the use of practical laminar screws in the subaxial spine. We used laminar screws in the subaxial cervical spine in two cases to prevent...

Background: The sagittal vertical axis (SVA) is important in the evaluation of spinal sagittal balance. Although the "fists-on-clavicles" (FOC) position has been widely used in radiographic examinations, it does not define shoulder flexion in detail. Meanwhile, in EOS imaging, the "hands-on-cheeks" (HOC) position is widely used but has not been we...

Entrapment of middle cluneal nerves induces low back pain and leg symptoms. The middle cluneal nerves can become spontaneously entrapped where this nerve pass under the long posterior sacroiliac ligament. A case of severe low back pain, which was completely treated by release of the middle cluneal nerve, was presented. Entrapment of middle cluneal...

上殿皮神経(SCN)は殿部外側に分布する皮神経であるが,絞扼例では腰痛のみならず坐骨神経痛様の下外側に及ぶ関連痛を呈することが報告されている.われわれは解剖用ご遺体12体(男性3体,女性9体)の死亡時平均年齢88歳の両側殿部の皮神経を調査した.腸骨稜上で絞扼されることの多い上殿皮神経内側枝の由来神経根は主に L4,L5から分布しており,坐骨神経様の関連痛を呈する解剖学的背景と考えられた. Superior cluneal nerves (SCN) are cutaneous nerves distributed at the gluteal region. Medial branch of SCN can become spontaneously entrapped under fasci...

Prospective comparative study of measuring pelvic incidence (PI) among standing X-ray images of whole spine and pelvis, and computed tomography (CT) in a cohort of patients. To analyze accuracies in measuring PI and other spino-pelvic parameters. Previous reports indicated relatively low agreement in measuring PI even among experienced spinal surge...

Abstracts Several authors have confirmed that 27 to 38 % of AIS patients had osteopenia. But few studies have assessed bone metabolism in AIS. This study assessed bone mineral density and bone metabolism in AIS patients using the bone metabolism markers, BAP and TRAP5b. The subjects were 49 consecutive adolescent AIS patients seen at our institutes...

Objective : Intramedullary high signal intensity on T2-weighted magnetic resonance imaging is frequently observed in patients with cervical spondylotic myelopathy. This finding does not correlate with neurological recovery after surgery. Previous studies have illustrated that the apparent diffusion coefficient (ADC) map is more sensitive than T2-we...

Background: Entrapment of the superior cluneal nerve (SCN) in an osteofibrous tunnel has been reported as a cause of low back pain (LBP). However, there are few reports on the prevalence of SCN disorder and there are several reports only on favorable outcomes of treatment of SCN disorder on LBP. The purposes of this prospective study were to inves...

Gorham's disease is a rare disorder of unknown etiology and variable clinical presentation and is characterized by the proliferation of lymphatic vessels associated with massive regional osteolysis. Although 10 cases involving the skull and cervical spine have been reported in the literature, little is available concerning the surgical treatment of...

To determine the static and dynamic radiological findings characteristic of symptomatic foraminal stenosis. Between 2006 and 2011, a total of 114 patients with unilateral leg pain due to L5 nerve root compression were screened to investigate the characteristic radiological findings of symptomatic foraminal stenosis. Static findings on sagittal CT i...

Study design: A retrospective case-control study. Objective: To assess the usefulness and reproducibility of 2 novel safe and simple radiographical measurements for atlantoaxial instability in children with Down syndrome. Summary of background data: In pediatric atlantoaxial instability, early diagnosis is important for improved outcomes becau...

Objective To characterize bone metabolism in AIS patients using bone metabolism markers. Summary of background data Although osteopenia is often associated with AIS, bone metabolism in this condition has not been assessed. Methods Bone mineral density (BMD) of the lumbar spine and bilateral proximal femurs (dual energy x-ray absorptio-metry) and bo...

Design: A retrospective study comparing screw positioning and associated complications between 2 different facet screw placement methods. Objective: To review the anatomic location, clinical safety, efficacy, and limitations of 2 facet screw placement techniques. Background: Facet screw fixation in the subaxial cervical spine penetrates 4 cort...

Background context Rapid diagnosis and accurate detection of etiological agents in pyogenic spinal infection (PSI) patients are important. Purpose The purpose of this study was to evaluate the clinical usefulness of methicillin-resistant Staphylococcus-specific polymerase chain reaction (MRS-PCR) and broad-range universal PCR (U-PCR) for diagnosin...

Lumbar intra-spinal canal stenosis is characterized by leg pain that intensifies during walking and intermittent claudication, while leg pain at rest is a characteristic neurological symptom of lumbar disc herniation. Until now, a correlation between leg pain at rest and symptomatic foraminal stenosis has not been reported. This is a prospective an...

Purpose Although osteopenia is often associated with AIS, studies on bone metabolism in relation to AIS have not yielded clear results. To characterize bone metabolism in AIS patients, a cross sectional study assessing bone metabolism and bone density was performed. Methods Using dual–energy X ray absorptiometry and bone metabolism markers (bone fo...

Adolescent idiopathic scoliosis (AIS) in humans is a lateral curvature of the spine often associated with osteopenia. It has recently been accepted that the development of AIS is closely associated with spinal overgrowth. Pinealectomy (PNX) in a chicken model consistently induces scoliosis with anatomic features similar to human AIS; however, the m...

Object: Entrapment of the superior cluneal nerve (SCN) in an osteofibrous tunnel in the space surrounded by the iliac crest and the thoracolumbar fascia is a cause of low-back pain (LBP). Several anatomical and surgical reports describe SCN entrapment as a cause of LBP, and a recent clinical study reported that patients with suspected SCN disorder...

Analysis of sagittal vertical axis (SVA) on lateral spine radiographs in healthy normal volunteers. To determine the optimal arm position with the smallest negative shift in SVA. Radiographic visualization of spinal and pelvic sagittal morphology is difficult with the participant in a relaxed standing position because of interference from the arms....

Background: Although there are several reports of paralysis developing after aggravation of the deformities of congenital kyphosis or kyphoscoliosis, the onset of myelopathy in middle-aged patients is rare. Objective: To describe a case of late onset thoracic myelopathy in a patient with anterolateral fused vertebrae. The progression of kyphoscolio...

Contralateral orchitis induced by unilateral testicular injury has been reported as sympathetic orchitis in men and experimental animals. In mice, experimental sympathetic orchitis (ESO) was first demonstrated in the C3H/He strain after experimental testicular trauma. Delayed-typed hypersensitivity (DTH) to testicular germ cells is induced by testi...

Obtaining a correct postoperative limb alignment is an important factor in achieving a successful clinical outcome after an opening-wedge high tibial osteotomy (OWHTO). To better predict some of the aspects that impact upon the clinical outcomes following this procedure, including postoperative correction loss and over correction, we examined the c...

Prospective analysis of sagittal vertical axis (SVA) on lateral spine radiographs using 3 different arm positions. To examine whether fists-on-clavicles position represents a functional standing position. Radiographic visualization of spinal and pelvic sagittal morphology is difficult during relaxed standing because of interference from the arms; h...

We evaluated the clinical outcomes, in terms of early weight bearing, of using opening wedge high tibial osteotomy (OWHTO) to treat spontaneous osteonecrosis of the medial femoral condyle of the knee (SONK) using TomoFix and artificial bone substitute. Damaged cartilage tissue was removed and drilling of the necrotic area followed by OWHTO was perf...

A retrospective study of patients undergoing palliative surgery for metastatic spinal tumors. To investigate short-term functional recovery and duration of improvement after palliative surgery, to correlate these outcomes with the revised Tokuhashi score, and to examine the relationship between function and neurologic deterioration. The revised Tok...

Study Design. A retrospective study of patients undergoing palliative surgery for metastatic spinal tumors. Objective. To investigate short-term functional recovery and duration of improvement after palliative surgery, to correlate these outcomes with the revised Tokuhashi score, and to examine the relationship between function and neurologic deter...

A retrospective case study of the use of intrapedicular partial pediculectomy (IPPP) to treat lumbar foraminal stenosis. To evaluate the clinical results of lumbar foraminal stenosis treated with IPPP. There is no gold standard for the surgical treatment of foraminal stenosis, which occurs in 8% of surgical cases of lumbar degenerative diseases. A...

A retrospective evaluation of diffusion-weighted imaging, apparent diffusion coefficient (ADC) maps, and T2-weighted images in patients with cervical compression myelopathy. To correlate high signal intensity on ADC maps and T2-weighted images to neurologic severity and radiologic spinal cord compression. Previous studies indicated that the ADC map...

Surgical site infection (SSI) needs to be prevented because its occurrence increases the patient's physical burden, hospital stay, and medical costs. We started SSI surveillance from January 2006 in our hospital and analysed the results and the risk factor of SSI. A total of 2986 patients who had undergone surgery in our hospital were enrolled in t...

Subjective ratings of discomfort were compared between a fixed lumbar support and lumbar support continuous passive motion (CPM) device. To compare a fixed lumbar support with a lumbar support CPM device during prolonged sitting. To prevent low back pain during prolonged sitting, an inflatable lumbar support CPM has been developed. There are no stu...

Retrospective case series with a control group. To measure the diagnostic performance of magnetic resonance imaging (MRI) and MR myelography (MRM) for symptomatic foraminal stenosis in patients who need surgery. MR images are extensively used in the evaluation of foraminal stenosis and are often used to evaluate nerves exiting from the foramen. The...

Atlantal lateral mass screw fixation is an increasingly popular procedure that is viewed as less demanding—and with lower risk of vertebral artery (VA) injury—than atlantoaxial transarticular fixation.2,3,5 We report a case in which the VA was injured during an atlantal lateral mass screw fixation procedure, however, to draw attention to this unusu...

Lipopolysaccharide (LPS) induces matrix degradation and markedly stimulates the production of several cytokines, i.e., interleukin-1beta, -6, and -10, by disc cells and chondrocytes. We performed a series of experiments to compare cellular responses of cells from the bovine intervertebral disc (nucleus pulposus and annulus fibrosus) and from bovine...

Most osteochondromas affect the long bones, but rarely originate in the spine. We report an extremely rare case of osteochondroma of the atlas causing obstructive sleep apnea syndrome (OSAS) in a 61-year-old female. The osteochondroma was removed completely using a transoral approach, and the symptoms of OSAS disappeared. A review of the literature...

This in vitro study used the alginate bead culture system to probe for differences in the effects of fibronectin fragment on cell proliferation and proteoglycan metabolism by different populations of intervertebral disc cells and articular chondrocytes. To compare the effects of fibronectin fragment on cell proliferation, and proteoglycan synthesis...

An in vivo study to radiographically and histologically assess a new method of induction of disc degeneration. OBJECTIVE.: To establish a reproducible rabbit model of disc degeneration by puncturing the anulus with needles of defined gauges and to compare it to the classic stab model. New treatment approaches to disc degeneration are of great inter...

The invasive schwannoma in the spine is a rare clinical entity. There have been no reports of schwannoma arising from tuberculous spine. The authors report on a case in which invasive cystic schwannoma arose at old tuberculous spine and paraplesia progressed by the tumor. The tumor excision and resection of the sequestra achieved satisfying neurolo...

Morphologic features of the dorsal root ganglia were investigated in patients with herniation of the nucleus pulposus by means of magnetic resonance myelography. This study was undertaken to assess morphologic changes of the dorsal root ganglia in patients with herniation of the nucleus pulposus and to determine the relations between the morphologi...

In an attempt to depict the anatomy of the nerve roots, we obtained magnetic resonance (MR) images of the lumbar spine in the coronal plane with the frequency-selective fat-suppression technique. With this technique, extradural anomalies were identified in 20 (6.7%) of 300 patients. We report the appearance on coronal MR images of six surgically co...

We report a case of Klinefelter's syndrome with multiply operated low back (MOB). Psychological and/or psychosocial problems related to MOB have been of recent interest in the field of orthopedic surgery. Based on psychiatric interviews, this case was diagnosed as a somatoform pain disorder of the DSM-III-R somatoform disorders. In addition to psyc...

Sixty-five patients who underwent wide laminectomy, Cotrel-Dubousset instrumentation, and fusion for lumbar degenerative disorders were reviewed radiographically to investigate the incidence and contributing factors of the postfusion instability at the adjacent segments immediately above or below the level of fusion. Thirty-four were men and 31 wer...

To evaluate reduction methods using two of the several types of Cotrel-Dubousset instrumentation (CDI), 39 patients with low-grade (Meyerding grades I and II [12]) lumbar spondylolisthesis were followed clinically and radiologically for a minimum of 6 months. Our surgical methods were classified into three types as follow: reduction by 2-level asse...

Thirty-five consecutive patients who underwent surgeries for decompression, and one-level fusions with Cotrel-Dubousset pedicle screws for spinal canal stenosis were included in this study. The relationship between bone mineral density of the lumbar spine and the rate of successful fusion and screw problems was studied. Bone mineral density of the...

Two cases of ganglion cysts in the lumbar spinal canal: MR findings. Ganglion cysts in the spinal canal are rare. To our knowledge, only 12 cases have been reported. In addition, ganglion cysts depicted by MR are extremely rare. We report the MR findings in two cases of ganglion cysts in the lumbar spinal canal. In both cases, the ganglion cysts we...

To prevent recurrence and avoid the second operation, the authors analyzed the clinical features and surgical outcome of 214 patients (157 males and 57 females) who underwent lumbar microdiscectomy, 16 of whom required second operation. The mean age was 34.6 years (range, 12-62 years). The average follow-up period was 4 years 5 months. The overall...

There have been some reports of ganglion cysts in the spinal canal in the English language medical literature, but no previous reports of an intraspinal extradural ganglion cyst shown on magnetic resonance images (MRI). (C) Lippincott-Raven Publishers.

In modern society many tasks that require prolonged sitting demand a static posture. Persons suffering low back pain are estimated to be approximately 10% of the population in Japan. We developed a device of lumbar lordotic continuous passive motion(CPM)to relieve low back pain in the prolonged sitting. Previously we reported a device with an air b...