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This study concerns intraosseous temperature changes during the use of piezosurgical inserts. On six fresh pig jaws heated to body temperature (36 °C), osteotomies and osteoplasties were performed in vitro with the Piezosurgery® 3 device (Mectron, Carasco, Italy) and various inserts. The intraosseous temperature increases were measured at a depth of 3 mm and at a distance of 1 mm from the working site using nickel–chromium/nickel temperature sensors. 20 °C Ringer's solution was used for cooling in an initial test series and 10 °C Ringer's in a second series. The processed bone was examined using digital volume tomography images to determine the ratio of cortical to cancellous bone thickness. Mean temperature increases of 4.4–10.9 °C were found; maximum temperature peaks were over 47 °C for an average of only 8.5 s. The type of piezosurgical insert had a marked influence on intraosseous temperature generation (p = 0.026); the thickness of the cortical bone and the temperature of the coolant did not. Coolant temperature had an influence on the bone cooling time (p = 0.013). The results show that correct use of the piezosurgery device does not give rise to prolonged temperature increases over 47 °C and hence does not cause any irreversible thermal damage in the bone.  相似文献   
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Background and importanceIn cardiogenic cerebral embolism, early recanalization is the most important factor for good prognosis. However, endovascular thrombectomy often fails to achieve recanalization. We present an open surgical embolectomy technique and discuss its advantages.Clinical presentationA 79-year-old woman developed right hemiparesis and severe aphasia. Magnetic resonance imaging revealed an acute cerebral infarction caused by left middle cerebral artery (MCA) occlusion. We attempted endovascular thrombectomy but failed because it was impossible to guide the catheter to the occlusion site. Hence, we converted to open surgical embolectomy. Sylvian fissure was widely opened. After confirming the range of thrombosis using indocyanine green videoangiography (ICGVAG), the proximal and distal arteries were secured, and a temporary clip was placed on the distal M2 to prevent distal thrombosis migration. MCA was cut approximately 3 mm from the bifurcation, and thrombosis was removed using micro-forceps. The proximal clip was simultaneously inserted but was not clamped because the thrombus was extruded by proximal vascular flow. Immediately after removing the thrombus, intense bleeding occurred from the proximal flow. An assistant clamped the proximal artery using the prepared clip, and the incised area of MCA was sutured using 9-0 threads. We finally confirmed blood flow after recanalization using ICGVAG. The time from skin incision to recanalization was 27 min. After the procedure, the patient developed slight aphasia but had no hemiparesis and was later transferred to a rehabilitation hospital.ConclusionOpen surgical embolectomy may be a secondary rescue treatment option in the case of endovascular thrombectomy failure.  相似文献   
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【摘要】目的 探讨骨髓间充质干细胞(BMSCs)和嗅黏膜神经干细胞(OM NSCs)共移植对大鼠脊髓损伤后运动功能的影响。方法 分别提取培养并鉴定大鼠BMSCs和OM NSCs。将60只雄性SPF级SD大鼠随机分为假手术组(仅做椎板切除,不损伤脊髓),对照组(在脊髓损伤区域注射5 μL生理盐水),BMSCs移植组(在脊髓损伤区域注射5 μL 5×104个细胞BMSCs单细胞悬液),OM NSCs移植组(在脊髓损伤区域注射5 μL 5×104个细胞 OM NSCs单细胞悬液,BMSCs和OM NSCs共移植组(在脊髓损伤区域注射5μL 1〖DK〗∶1 5×104个细胞BMSCs和OM NSCs细胞混悬液)。细胞移植后第1、3、7、14、21、28天分别对大鼠进行BBB评分,28天后处死大鼠,分离脊髓组织,进行免疫荧光染色观察细胞迁移情况。结果 造模后,大鼠双后肢瘫痪,BBB评分0分。细胞移植后14天起,与对照组相比,干细胞移植组运动功能有显著改善,BBB评分比较差异具有统计学意义(P<005)。与BMSCs移植组和OM NSCs移植组相比,移植后21、28天,共移植组BBB评分显著增加(P<005)。免疫荧光观察结果表明,脊髓损伤28天后,损伤区脊髓内可见空泡形成,两种干细胞聚集在空泡周围,BMSCs在损伤区分布较为集中,而OM NSCs相对散在分布,细胞较为伸展。结论 干细胞移植可以一定程度上恢复脊髓损伤大鼠的运动功能,BMSCs和OM NSCs两种干细胞共移植效果优于单细胞移植。  相似文献   
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Background contextApproximately 25% of vertebroplasty patients experience subsequent fractures within 1 year of treatment, and vertebrae adjacent to the cemented level are up to three times more likely to fracture than those further away. The increased risk of adjacent fractures postaugmentation raises concerns that treatment of osteoporotic compression fractures with vertebroplasty may negatively impact spine biomechanics.PurposeTo quantify the biomechanical effects of vertebroplasty on adjacent intervertebral discs (IVDs) and vertebral bodies (VBs).Study designA biomechanics study was conducted using cadaveric thoracolumbar spinal columns from elderly women (age range, 51–98 years).MethodsFive level motion segments (T11–L3) were assigned to a vertebroplasty treated or untreated control group (n=10/group) such that bone mineral density (BMD), trabecular architecture, and age were similar between groups. Compression fractures were created in the L1 vertebra of all specimens, and polymethylmethacrylate bone cement was injected into the fractured vertebra of vertebroplasty specimens. All spine segments underwent cyclic axial compression for 115,000 cycles. Microcomputed tomography imaging was performed before and after cyclic loading to quantify compression in adjacent VBs and IVDs.ResultsCyclic loading increased strains 3% on average in the vertebroplasty group when compared with controls after 115,000 cycles. This global strain manifested locally as approximately fourfold more compression in the superior VB (T12) and two- to fourfold higher axial and circumferential deformations in the superior IVD (T12–L1) of vertebroplasty-treated specimens when compared with untreated controls. Low BMD and high cement fill were significant factors that explained the increased strain in the vertebroplasty-treated group.ConclusionsThese data indicate that vertebroplasty alters spine biomechanics resulting in increased compression of adjacent VB and IVD in severely osteoporotic women and may be the basis for clinical reports of adjacent fractures after vertebroplasty.  相似文献   
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Background contextVertebral hemangiomata are ubiquitous bone tumors. Often multiple, they are generally benign in nature and slow growing. They typically have a predictable radiographic appearance. Occasionally, hemangiomata may behave in a more aggressive manner, causing pathologic fracture or even symptoms/signs of nerve compression. In such cases, one must be careful not to assume that an atypical hemangioma is responsible. Coexisting, more malignant processes may be present and sometimes may be radiographically undetectable in the setting of acute fracture. This was the case in our patient.Study designCase report/university spine surgery center.MethodsThe patient underwent a corpectomy of her affected vertebra with conversion to a total spondylectomy when intraoperative frozen section was consistent with plasma cell neoplasm. A reconstruction with vertebral body replacement and fusion through anterior and posterior approaches was completed. Subsequently, the literature was reviewed for other cases of atypical hemangiomata to investigate the incidence of coexistent lesions.ResultsThis patient presented with pain secondary to an unstable pathologic vertebral body fracture. Surgery to stabilize her spine was elected. Intraoperative recognition of abnormal-appearing tissue led to the diagnosis of a plasma cell neoplasm that was not seen on imaging. Coexistent in the same vertebra was hemangiomatous tissue that was visible on preoperative imaging.ConclusionsThere are rare reports of aggressively behaving hemangiomata that mainly have occurred in the thoracic spine. There have been no reports of the coexistence of a hemangioma and a plasma cell tumor in the same vertebral level in the setting of acute compression fracture.  相似文献   
27.
Purpose/Aim of the study: The purpose of this analysis was to compare the clinical outcomes of vertebral fusion with allograft versus autograft bone. Materials and Methods: Medline, PubMed, Cochrane, EMBASE, and Google Scholar databases were searched until July 27, 2015 using the keywords: lumbar vertebrae, surgery, spondylolisthesis, bone transplantation, allograft, autograft. Inclusion criteria were randomized controlled trials (RCTs), two-arm prospective studies, retrospective studies, and cohort studies comparing the results of autograft and allograft in patients receiving lumbar spinal fusion. The outcomes were changes of Oswestry Disability Index (ODI) and visual analogue scale (VAS) pain scores from baseline at 1, 2, and 3 years after surgery and fusion rates. Results: Of 154 studies identified in the database searches, five were included in the quantitative analysis (one RCT, one prospective, and three retrospective studies). The mean patient age ranged from approximately 40 to 65 years, and approximately half of the patients were males. The total number of patients who received allografts was 333 and the total that received autografts was 175. The analysis revealed the change of ODI and VAS pain score at 1, 2 and 3 years was similar between the allograft and autograft groups (all, p > .05), as were the fusion rates (p > .05). Conclusions: Both allograft and autograft provide acceptable outcomes for spinal fusion.  相似文献   
28.

目的  探讨经伤椎椎弓根复位植骨结合后路内固定术治疗胸腰椎陈旧性骨折的临床疗效。方法  选择2013年1月-2014年6月河北省唐山市第二医院脊柱外科28例胸腰椎陈旧性骨折患者(伤后3~5周)。采用经伤椎椎弓根复位加椎体内植骨并后路椎弓根钉内固定治疗。观察术前、术后1周和术后3个月椎体高度压缩率、伤椎Cobb角、ODI评分及椎管侵占率等,并进行比较分析。结果  28例患者均成功实施手术并获随访,时间6~18(10.6±4.8)个月。伤椎高度矫正率约93%,椎体高度压缩率、伤椎Cobb角、ODI评分及椎管侵占率较术前均有明显改善。术前与术后1周及术后3个月比较差异有统计学意义(P <0.05);除ODI评分外,术后1个周与术后3个月比较差异无统计学意义(P >0.05)。无内固定松动、断裂及神经损伤等并发症发生,植骨未吸收。结论  经伤椎椎弓根复位加椎体内植骨并后路椎弓根钉内固定对于治疗胸腰椎陈旧性骨折,可增加前柱支撑,减少椎体高度丢失,疗效满意。

  相似文献   
29.
Nonsteroidal anti-inflammatory drugs (NSAIDs) have been reported to have weak but beneficial effects on bone health, including fracture risk, but many epidemiological studies are likely confounded. We explored the relationship between NSAIDs and fracture risk in a post hoc analysis of a well-documented, randomized, placebo-controlled study of the bisphosphonate, clodronate, in which treatment reduced osteoporotic fracture risk by 23%. Concurrent medication use at baseline was used to identify those prescribed oral NSAIDs. Only verified, incident fractures were included in the analysis. A total of 1082 (20.8%) women reported use of NSAIDs at baseline. They were slightly, but significantly, younger (mean 79 versus 80 years, p = 0.004), heavier (mean 66.7 versus 64.7 kg, p < 0.001) than nonusers, with slightly higher femoral neck bone mineral density (FN-BMD, 0.66 versus 0.64 g/cm2, p < 0.001). In an adjusted model, NSAID use was associated with a significant increase in osteoporotic fracture risk over the 3-year study period (hazard ratio [HR] 1.27; 95% confidence interval [CI], 1.01–1.62; p = 0.039). However, this increase in risk was not statistically significant in the placebo group (HR 1.11; 95% CI, 0.81–1.52). In women receiving clodronate, the effect of the bisphosphonate to reduce osteoporotic fracture risk was not observed in those receiving NSAIDs (HR 0.95; 95% CI, 0.65–1.41; p = 0.81) in contrast to those not using NSAIDs (HR 0.71; 95% CI, 0.58–0.89; p = 0.002). In a subset with hip BMD repeated at 3 years, BMD loss during clodronate therapy was greater in those women receiving NSAIDs than in nonusers (eg, total hip −2.75% versus −1.27%, p = 0.078; femoral neck −3.06% versus −1.12%, p = 0.028), and was not significantly different from that observed in women receiving placebo. The efficacy of the bisphosphonate, clodronate, to reduce fracture risk was largely negated in those receiving NSAIDs. Although the mechanism is unclear, this clinically significant observation requires exploration in studies of commonly used bisphosphonates. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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No study so far has paid attention to strabismus-related spinal imbalance. This study aimed to determine the epidemiology of thoracic scoliosis in children and adolescents with strabismus and investigate the association of two diseases. A cross-sectional study. Study group consists of 1935 consecutive candidates for strabismus surgery (4–18 years); Control group consists of the age- and sex-matched patients with respiratory diseases. All subjects underwent a screening program based on chest plain radiographs using the Cobb method. Their demographic information, clinical variables and results of Cobb angle were recorded and analyzed. A significantly higher prevalence of thoracic scoliosis (289/1935, 14.94% versus 58/1935, 3.00%) was found in study group compared with control group. Among strabismic patients, the coronal thoracic scoliosis curve mainly distributed in right and in main thoracic (198/289) and in the curves 10°–19° (224/289); Age range 7–9 years (103/1935), female (179/1935) and concomitant exotropia patients (159/851) were more likely to have thoracic scoliosis. According to the logistic regression, thoracic scoliosis had no significant association with age, BMI, duration of illness and onset age (p > 0.05). However, gender, BCVA, type of strabismus and degree of strabismus showed a significant relationship with the prevalence of thoracic scoliosis (p < 0.05). With a pooled prevalence of 14.94%, strabismus patients showed a great higher risk of developing thoracic scoliosis. Screening for scoliosis in strabismus patients can be helpful to discover a high prevalence of potential coronal scoliosis. More attention should be paid to ophthalmological problems in patients with scoliosis. These slides can be retrieved under Electronic Supplementary Material.  相似文献   
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