In Brief Study Design. Retrospective study of 66 patients who underwent laminoplasty for treatment of cervical myelopathy due to ossification of the posterior longitudinal ligament (OPLL). Objectives. The present study describes surgical results of laminoplasty for treatment of cervical myelopathy due to OPLL and aims to clarify 1) factors predicting outcome and 2) limitations of laminoplasty. Summary of Background Data. During the period 1986 and 1996, laminoplasty was the only surgical treatment selected for cervical myelopathy at our institutions. Methods. We reviewed data obtained in 66 patients who underwent laminoplasty for treatment of cervical myelopathy due to OPLL. Mean duration of follow-up was 10.2 years (range, 5–20 years). Surgical outcomes were assessed using the Japanese Orthopaedic Association (JOA) scoring system for cervical myelopathy. Results. Surgical outcome was significantly poorer in patients with occupying ratio greater than 60%. Multiple regression analysis showed that the most significant predictor of poor outcome after laminoplasty was hill-shaped ossification, followed by lower preoperative JOA score, postoperative change in cervical alignment, and older age at surgery. Conclusions. Laminoplasty is effective and safe for most patients with occupying ratio of OPLL less than 60% and plateau-shaped ossification. However, neurologic outcome of laminoplasty for cervical OPLL was poor or fair in patients with occupying ratio greater than 60% and/or hill-shaped ossification. Laminoplasty is effective and safe for most patients with occupying ratio of OPLL <60% and plateau-shaped ossification. However, surgical outcome of laminoplasty would be poor when occupying ratio of OPLL is ≥60% and/or when the ossified lesion is hill-shaped with sharp angulation of the spinal cord.
Expanded Polystyrene foam (EPS) is a chemically inert and 100% recyclable material that is lightweight and has a good compression strength per weight ratio; however, its current construction use is mostly limited to insulation or landfill.The key concept of this paper is to develop an EPS composite to create an ultra-lightweight long-span sustainable roofing structure by integrating the minimum necessary structural tension layer with a certified fire protection system.The authors present this concept in the following four steps, 1) EPS composite structural specimen test, 2) structural optimisation of the reversed displacement model, 3) discretisation with developable surfaces and 4) CNC hotwire rapid prototyping and assembly in scaled prototypes.The Cloud Arch is an economical, material-efficient, thermally insulated, quickly assembled ultra-lightweight construction that eliminates the need for formworks for long-span structures.It can be applied to many types of column-free spaces, such as in factories, gymnasiums, markets and cafeterias.
Introduction: Posterior lumbar interbody fusion (PLIF) has produced satisfactory clinical outcomes; however, all previous reports have only included evaluations by surgeon-based methods. The purpose of this study was to investigate patient-based surgical outcomes and the factors associated with patient satisfaction for PLIF. Methods: Patients who underwent PLIF for lumbar spondylolisthesis were reviewed (n=443). The average follow-up period was 8 years. Surgical outcomes were assessed using an original questionnaire, a numerical rating scale (NRS), the 36-Item Short Form Health Survey (SF-36), the Japanese Orthopedic Association (JOA) score, and the recovery rate. The original questionnaire consisted of five categories, with patient-evaluated score out of 100 points for surgery, satisfaction, improvement, recommendation to others, and willingness to undergo repeat surgery on a 5-point scale. According to the questionnaire responses, patient-based outcomes were divided into three groups: positive, intermediate, and negative and were compared with the NRS, SF-36, and JOA scores. Furthermore, factors associated with patient satisfaction were examined. Results: A total of 273 patients responded. Response rate was 62%. The average patient-evaluated score for surgery was 82 points. In terms of satisfaction section, positive, intermediate, and negative response rates were 82%, 7%, and 11%, respectively. With respect to other sections, positive, intermediate, and negative response rates were 87%, 7%, and 6% in improvement section; 66%, 23%, and 11% in recommending section; and 72%, 18%, and 10% in repeat section, respectively. The average pre- and postoperative JOA scores were 12 and 24, respectively. Significant correlations were detected between patient-based surgical outcomes and the NRS scores, physical component scores of the SF-36, and the JOA score. Postoperative permanent motor loss and multiple revision surgery were the major factors related to a negative response. Conclusions: High satisfaction rate to PLIF and significant correlation between patient- and surgeon-based surgical outcomes were detected. Postoperative permanent motor loss and multiple revision surgery were the major factors related to a negative response.
Surgical management of massive ossification of the posterior longitudinal ligament (OPLL) is challenging. To reduce surgical complications, the authors have performed anterior selective stabilization combined with laminoplasty (antSS+LP) for massive OPLL since 2012. This study aimed to elucidate the short-term outcome of the antSS+LP procedure.
This paper demonstrates how digitally fabricated vacuumformed components can provide a new type of effi cient construction applicable to architecture.Vacuum forming has the advantage of rapid mass-production capability of 3D curved forms.Recent digital fabrication technologies, such as 3D CAD and CNC machining, have dramatically reduced the cost and time for making the mould.In combination with biodegradable plastic, such as PLA (poly lactic acid) made of biopolymer, it could open up new type of sustainable construction system, which is applicable for temporal disaster housings or exhibition booths.
We experimentally demonstrated 10 km transmission of 225 Gb/s PAM4 modulation signal using our developed high-speed EMLs with a hybrid waveguide structure. Clear eye patterns were observed with 5 taps of TDECQ reference equalizer.
Object The management of isthmic spondylolisthesis remains controversial, especially with respect to reduction. There have been no reports regarding appropriate slip reduction. The purpose of this study was to investigate the following issues: 1) surgical outcomes of posterior lumbar interbody fusion (PLIF) with total facetectomy for low-dysplastic isthmic spondylolisthesis, including postoperative complications; 2) effects of slip reduction on surgical outcomes; and 3) appropriate slip reduction. Methods A total of 106 patients who underwent PLIF with total facetectomy for low-dysplastic isthmic spondylolisthesis and who were followed for at least 2 years were reviewed. The average follow-up period was 8 years. Surgical outcomes, including the scores assessed using the Japanese Orthopaedic Association scoring system, the recovery rate, and postoperative complications were investigated. As for radiographic evaluations, pre- and postoperative slip and disc height, instrumentation failure, and fusion status were also examined. Results The pre- and postoperative average Japanese Orthopaedic Association scores were 14 (range 3–25) and 25 (range 11–29) points, respectively. The average recovery rate was 73% (range 0%–100%). The average pre- and postoperative slip was 24% and 10%, respectively. A significant correlation between postoperative slip and clinical outcomes was found; clinical outcomes were better in proportion to slip reduction. Although no statistical difference was detected in clinical outcomes between postoperative slip of less than 10% and from 10% to 20%, patients with postoperative slip of more than 20% showed significantly worse clinical outcomes. Postoperative complications included neurological deficits in 7 patients (transient motor loss in 6 and permanent motor loss in 1), instrumentation failures in 7, adjacent-segment degeneration in 5, and nonunion in 4. Instrumentation failures occurred significantly more often in patients with more slip reduction, although slip reduction did not affect the other postoperative complications. All patients with instrumentation failure showed postoperative slip reduction within 10%. Conclusions The use of PLIF with total facetectomy for low-dysplastic isthmic spondylolisthesis appears to produce satisfactory clinical outcomes, with an average of 73% recovery rate and few postoperative complications. Although clinical outcomes were better in proportion to slip reduction, excessive reduction caused instrumentation failure, and patients with less reduction demonstrated worse clinical outcomes. Appropriate reduction resulted in a postoperative slip ranging from 10% to 20%.
Age-related alterations of gene expression of transforming growth factor β1 (TGF-β1) and its receptors ( T β Rs ) in tissues derived from rat intervertebral discs were assessed together with TGF-β1-dependent proteoglycan synthesis by the cultured disc cells. Disc tissues and cells were individually harvested from two sites of the coccygeal vertebrae, namely the nucleus pulposus (NP) and annulus fibrosus (AF), which are major distinct components of the intervertebral discs. Semi-quantitative RT-PCR analysis indicated that the level of gene expression of TGF-β1/TGF-β1 receptor type I (TβR-I) of NP decreased with age. In AF, the level of TGF-β1/ T β Rs gene expression did not apparently differ with age. Consistent with the RT-PCR results, stimulation of proteoglycan synthesis by TGF-β1 in NP cells decreased with age. Proteoglycan synthesis by AF cells was also stimulated by TGF-β1. However, levels of this stimulation by AF cells were identical. The present findings indicate that the genetic expression of TGF-β1/ T β R -I and TGF-β1-dependent proteoglycan synthesis decreased with age in NP cells, and further suggest that a loss of proteoglycan synthesis with age in the intervertebral disc is at least in part due to the transcriptional down regulation of TGF-β1/ T βR-I and decreased synthetic ability of proteoglycans in response to TGF-β1 by NP cells.
Study Design Case report. Objective To present two cases of neurogenic shock that occurred immediately following posterior lumbar interbody fusion (PLIF) and that appeared to have been caused by the vasovagal reflex after dural injury and incarceration of the cauda equina. Case Report We present two cases of neurogenic shock that occurred immediately following PLIF. One patient had bradycardia, and the other developed cardiac arrest just after closing the surgical incision and opening the drainage tube. Cardiopulmonary resuscitation was performed immediately, and the patients recovered successfully, but they showed severe motor loss after awakening. The results of laboratory data, chest X-ray, electrocardiogram, computed tomography, and echocardiography ruled out pulmonary embolism, hemorrhagic shock, and cardiogenic shock. Although the reasons for the postoperative shock were obscure, reoperation was performed to explore the cause of paralysis. At reoperation, a cerebrospinal fluid collection and the incarceration of multiple cauda equina rootlets through a small dural tear were observed. The incarcerated cauda equina rootlets were reduced, and the dural defect was closed. In both cases, the reoperation was uneventful. From the intraoperative findings at reoperation, it was thought that the pathology was neurogenic shock via the vasovagal reflex. Conclusion Incarceration of multiple cauda equina rootlets following the accidental dural tear by suction drainage caused a sudden decrease of cerebrospinal fluid pressure and traction of the cauda equina, which may have led to the vasovagal reflex.
'/%3e%3cuse xlink:href='%23a' transform='rotate(60)'/%3e%3ccircle r='17' fill='%23000095'/%3e%3ccircle r='15' fill='%23fff'/%3e%3c/svg%3e)
