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991.
992.
Kuan Wang MD Chenghua Jiang PhD Lejun Wang PhD Huihao Wang MD Wenxin Niu PhD 《The spine journal》2018,18(12):2288-2296
BACKGROUND CONTEXT
Anterior vertebral body osteophytes are common with degeneration but their biomechanical influence on the whole lumbar spine remains unclear.PURPOSE
To investigate the biomechanical influence of anterior vertebral body osteophytes on the whole lumbar spine.STUDY DESIGN/SETTING
This is a study using finite element analysis.OUTCOME MEASURES
Intersegmental rotation, maximum Mises stress, and intradiscal pressure on the intervertebral discs of different lumbar levels were calculated.METHODS
A finite element model of an intact lumbar spine was constructed and validated against in vitro studies. The modified models, which had different degrees of anterior vertebral body osteophyte formation (OF) in combination with disc space narrowing, were applied with physiological loadings.RESULTS
The lumbar levels with various degrees of OF altered the kinematics of these levels, which also affected the whole lumbar spine. In flexion and lateral bending, the segment that was one level inferior to the vertebra with OF showed a trend towards increased range of motion. On the intervertebral discs that were one level inferior to the OF level, a trend towards increase in the maximum von Mises stress was found on the annulus.CONCLUSIONS
Segments adjacent to levels with anterior vertebral body osteophytes showed increased intersegmental rotation and maximum stress. Further clinical observation should be performed to verify the results in vivo. 相似文献993.
目的:观察经皮椎间孔镜技术治疗腰椎间盘突出症的临床疗效。方法:回顾性分析2016年08月—2017年08月应用经皮椎间孔镜技术治疗单一节段腰椎间盘突出症患者78例,采用疼痛视觉模拟评分法(VAS)、ODI功能障碍指数评分评价患者疼痛及腰椎功能改善情况,改良MacNab评价临床疗效。结果:本组78例患者术后VAS、ODI评分较术前显著降低,差异有统计学意义;但术后6月、12个月VAS、ODI评分无显著性差异。术后12个月采用改良MacNab标准评价疗效,优良率93.59%。结论:经皮椎间孔镜技术治疗腰椎间盘突出症具有创伤小、术后脊柱结构稳定、近期临床疗效可靠等优势,值得临床医师推广应用。 相似文献
994.
患者女,11岁,两年前无明显诱因出现腰部弯曲时疼痛,伴屈曲受限.MRI检查:腰椎平扫T1、T2加权像上均可见L2水平椎管内高低混杂信号,大小约2.4 cm×2.0 cm×3.0 cm,边缘可见条状低信号,其上下方均有条状低信号相连,脊髓明显受压移位(图1).CE-MRA检查可见椎管内异常血管团,其上方和下方均可见引流动脉,远端引流动脉通过L5S1双侧椎间孔与双侧髂内动脉交通(图2,3).DSA证实为椎管内动脉瘤,瘤体位于L2水平椎管内,载瘤动脉上,胸肋间动脉单独供血,上方可见引流静脉(图4).超声Doppler证实瘤内可见明显的旋流信号,其头侧可见载瘤动脉,血流方向是由头侧向尾侧流入瘤体内,载瘤动脉血流速度Vmax=117.7 cm/s.经后路手术进入椎管,可见瘤体搏动. 相似文献
995.
Shibao Lu Siyuan Sun Chao Kong Wenzhi Sun Hailiang Hu Qingyi Wang Yong Hai 《The spine journal》2018,18(6):917-925
Background Context
Lumbar total disc replacement (TDR) operation represents an alternative to lumbar fusion for the treatment of symptomatic lumbar intervertebral disc degeneration and has gained increasing attention in recent years.Purpose
This study aimed to assess clinical outcomes in a cohort of patients with TDR and the long-term survival rate of the prostheses.Study Design
This is a retrospective, single-center clinical study.Patient Sample
The sample comprised 30 patients, giving a total of 35 prostheses after an average follow-up (FU) of 15.2 years following TDR, which was performed for the treatment of lumbar degenerative disc disease.Outcome Measures
Clinical evaluation included visual analog scale (VAS) and the Oswestry Disability Index (ODI). Radiological parameters of intervertebral disc height (IDH), range of motion (ROM), lumbar lordosis, lumbar scoliosis, and prosthesis position were evaluated in surgical and adjacent levels. Complications and re-operation rates were also assessed.Methods
Clinical evaluation and radiological parameters were evaluated preoperatively and at final FU. All data were collected by members of our department, including research assistants and nurses who were not involved in the decision making of this study.Results
Thirty of the 35 patients participated in the final FU. The cumulative survival rate of the prosthesis at a mean FU of 15.4 years was 100%. The clinical success rate was 93.3%. The VAS and ODI scores at final FU were significantly lower than preoperatively (p<.001). The average ROM of the operated and superior adjacent segment decreased significantly at the final FU, whereas the inferior adjacent segment was not affected. The IDH of all surgical and adjacent levels were well maintained at the final FU. Ten patients had a lumbar scoliosis >3° and the mean angle was 8.5°, of which 7 had left convex curvature. Three prostheses were offset more than 5?mm from the midline on the coronal plane. Four prostheses showed subsidence. Twenty-six operative segments and five adjacent segments showed heterotopic ossification. Two patients of the total 35-patient cohort underwent a secondary operation.Conclusions
Satisfactory clinical results and good prosthesis survival can be achieved in the long term. Lumbar TDR surgeries also have the potential to reduce the incidence of adjacent segment disease. 相似文献996.
Background Context
Nerve root compression causing symptomatic radiculopathy can occur within the intervertebral foramen. Sagittal magnetic resonance imaging (MRI) sequences are reliable in detection of nerve root contact to intraforaminal disc material, but a clinically relevant classification of degree of contact is lacking.Purpose
This study aimed to investigate a potential relation of amount of contact between intraforaminal disc material and nerve root to clinical findings and response after periradicular corticosteroid infiltration.Study Design
A post hoc analysis of a prospective cohort was carried out.Patient Sample
Patients who underwent computed tomography (CT)-guided periradicular corticosteroid infiltration (L1–L5) at our institution (January 2014 to May 2016) were included.Outcome Measures
The medical records and radiographic imaging were reviewed.Methods
T2-weighted MRI of the lumbar spine of patients with single-level symptomatic radiculopathy with (responders, n=28) or without (non-responders, n=14) pain relief after periradicular infiltration with corticosteroids were measured and compared by two independent readers to determine the amount of intraforaminal nerve root contact with the intervertebral disc (“melting” of the T2-hypointense signal). Pain relief was defined with a pain level decrease of >50% on a visual analogue scale and lack of pain relief with a pain level decrease of <25%, respectively. The amount of T2-hypointensity melting of disc and nerve root was categorized to 0%, 1%–25%, and over 25%.Results
Reader one identified 0% T2-melting in none of the responders, 1%–25% melting in 13 patients (46.4%), 26%–50% in 15 of the 28 patients (53.6%) with pain relief after periradicular corticosteroid infiltration (responders), with a mean amount of T2-melting of 5.9±2.1?mm, whereas the non-responder group had 0% T2-melting in 2 patients (14.3%), 1%–25% T2-melting in 11 patients (78.6%), and 26%–50% in 1 patient (7.1%), with a mean amount of T2-melting of 2.6±1.9?mm (p<.05).Reader two identified 0% T2-melting in none, 1%–25% T2-melting in 15 (53.6%) patients, and 26%–50% in 13 of the 28 responders (46.4%), with mean amount of 6.3±1.9?mm. In the non-responder group 0% T2-melting was seen in 3 patients (21.4%), 1%–25% T2-melting in 10 patients (71.4%), and 26%–50% in 1 patient (7.1%), with a mean amount of T2-melting of 2.7±1.9?mm (p<.05). None of the MRI showed T2-melting in over 50% of the circumference of the intraforaminal nerve root.A T2-melting of >25% had a high specificity of 93% but a sensitivity of 50%, thus a positive likelihood ratio of 7.5, to identify those with a pain relief of more than 50% after infiltration.Conclusion
The amount of T2-melting of disc material and nerve root on sagittal MRI (>25%) predicts the amount of pain relief by periradicular infiltration in patients with intraforaminal nerve root irritation. 相似文献997.
Background and purpose
There are no significant differences in outcomes between patients receiving inpatient and day-case lumbar microdiscectomy, but the latter is still underused in the NHS. Here we aimed to identify factors contributing to successful same-day discharge in day-case patients.Methods
This was a retrospective observational study of patients undergoing elective lumbar microdiscectomy between August 2012 and December 2014. Age, gender, day of surgery, distance to hospital, ASA grade, regular opiate use, smoking status, order on the operating list, and side and level of surgery were examined by logistic regression to assess their influence on same-day discharge.Results
28/95 (29.5%) patients were discharged on the day of surgery. Age (p = 0.041), ASA grade (p = 0.016), distance to hospital (p = 0.011), and position on the list (p = 0.004) were associated with day-case discharge by univariate analysis. ASA grade (p = 0.032; OR 0.176), distance to hospital (p = 0.003; OR 0.965), and position on the operating list (morning case; p = 0.011; OR 8.901) remained significant in multivariate analysis. Thirteen (13.7%) patients were identified who could have been managed as day cases had they been listed for morning operations.Conclusions
Day-case lumbar microdiscectomy is viable when patients are carefully selected. Younger, fit patients living close to the hospital and operated on in the morning are more likely to be discharged on the same day. Knowledge of these factors while planning elective lists can help optimise bed space and improve spinal services. 相似文献998.
Björn Knutsson Sebastian Mukka Jens Wahlström Bengt Järvholm Arkan S. Sayed-Noor 《The spine journal》2018,18(8):1313-1317
Background Context
Tobacco smoking is an injurious habit associated with a number of chronic disorders. Its influence on disc metabolism and degeneration including lumbar spinal stenosis (LSS) has been investigated in the literature.Purpose
We aimed to investigate whether tobacco smoking is an independent risk factor for undergoing surgical intervention for LSS.Study Design/Setting
This is a prospective cohort study.Patient Sample
The patient sample of 331,941 workers was derived from a Swedish nationwide occupational surveillance program for construction workers.Outcome Measure
The outcome measure included the incidence of undergoing surgical intervention for LSS in tobacco smokers versus no smokers.Materials and Methods
At inclusion, age, sex, body mass index (BMI), workers' job title, and self-reported smoking habits were registered. The workers were divided into four categories: never smoked, former smoker, moderate current (1–14 cigarettes/day), and heavy current (≥15 cigarettes/day). Patients who underwent a surgically treated LSS were defined using the relevant International Classification of Diseases (ICD) disease code derived from the Swedish National Patient Register.Results
A total of 331,941 participants were included in the analysis. Forty-four percent of the participants were non-smokers, 16% were former smokers, 26% were moderate smokers, and 14% were heavy smokers. The vast majority of construction workers were males (95%). During the average follow-up of 30.7 years, 1,623 participants were surgically treated for LSS. The incidence rate ratio (IRRs) of LSS varied across smoking categories, with the highest values found in heavy smokers. Compared with non-smokers, all smoking categories show an increased incidence of surgically treated LSS. The findings were consistent even when the comparison was performed for participants with BMIs between 18.5 and 25 and for participants aged between 40 and 74 years.Conclusions
Tobacco smoking is associated with an increased incidence of surgically treated LSS. The effect seems to be dose related, whereby heavy smokers have a higher risk than moderate or former smokers. 相似文献999.
正先天性脊柱畸形是由于脊柱发育缺陷导致的脊柱形态及结构功能异常,在婴儿中其发生率约为1/1 000~([1])。颈椎半椎体畸形是先天性脊柱畸形的一种,常见于Klippel-Feil综合征,与胸腰椎畸形相比,此类畸形在临床上更为罕见。Deburge等~([2])和Winter等~([3])分别于1981年首次报道颈椎半椎体畸形及其治疗方法,Ruf等~([1])在2005年对其进行详细阐述。近年来,临床报道了多例颈椎半椎体畸形病例,治疗方法各有不同~([4-6])。本院2015年收治C_5半 相似文献
1000.
Alex S. Aires Leici M. Reichert Rodrigo T. Müller Marco B. Andrade 《Anatomical record (Hoboken, N.J. : 2007)》2022,305(9):2079-2098
The notarium is a rigid bony structure, which resulted from the fusion of thoracic vertebrae of some pterosaurs and birds. It is high variable, ranging from two to six fused thoracic vertebrae. In this study, we reviewed and analyzed approximately 270 specimens of neornithine birds (representing 80% of the living orders) and some fossils in order to identify the number of fused vertebrae, degree and sites of vertebral fusion, occurrence of sutures, and other structures of potential phylogenetic and functional significance. These data were analyzed using a recent time-calibrated molecular phylogenetic tree and principal component analyses analysis evaluating the relationship with long bones in order to reconstruct macroevolutionary trends related to the evolution of the notarium. The occurrence of this structure shows a mosaic distribution over neornithine phylogeny, originating several times independently, especially during the Paleogene, in predominantly ground-dwelling forms. The notarium of these groups is characterized by: neural spines fused into single structure, intervertebral openings small to absent, large ventral keels forming ventral plates, and fused transverse processes. Derived neornithines, such as aquatic forms and long-legged birds, have a tendency to display a decreased degree of fusion between the vertebrae, which may indicate a reduction or disappearance of the notarium. 相似文献