Is there an impact of cervical plating on the development of adjacent segment degeneration following Smith-Robinson procedure? A magnetic resonance imaging study of 84 patients with a 24-year follow-up

BACKGROUND CONTEXT

Anterior cervical discectomy and fusion (ACDF) without and with cervical plating (ACDF+CP) are accepted surgical techniques for the treatment of degenerative cervical disc disorders. The effect of CP on the development of adjacent segment degeneration (ASD) remains unclear.

Coconut oil protects against light-induced retina degeneration in male Wistar rats

The retinoprotective effect of Cocos nucifera oil (CNO) was investigated. Twenty male Wistar rats weighing 140?g and 180?g were randomly divided into four groups comprising of five animals each. The control group received distilled water. Retinal degeneration was induced in the remaining three groups by exposing the animals to 5,000?lux of bright white light for two hours. Prior to the light exposure, the light model group (LMG) received distilled water for 14 days, low Cocos nucifera oil (LCNO) group received 5?ml/kg of CNO for 14 days, and the high Cocos nucifera oil (HCNO) group received 10?ml/kg of CNO for 14 days. The treatments continued for 7 days after exposure to light. On the eight day, the animals were euthanised and their retinas isolated. The right retinas and occipital cortices of the animals were prepared for histological evaluation while the homogenates of the left retinas were used for biochemical assay. The results show that CNO significantly (p?<?0.05) reduced caspase-3 activity from 1.15?±?0.054?ng/ml to 0.434?±?0.095?ng/ml (LMG versus LCNO) and malondialdehyde concentration. There was no significant difference in the total antioxidant capacity in the retinas of the rats. However, LMG showed a significant increase in catalase activity. CNO was able to preserve the retinal morphology while LMG showed a distorted retinal layer and significant reduction (p?<?0.05) in retina thickness. CNO was unable to prevent perineural vacuolations in the occipital cortices of the rats. In conclusion, Cocos nucifera oil produced retino-protective effect via anti-oxidative and anti-apoptotic mechanisms.     

兔牙本质磷酸蛋白稳定性分析

目的：探讨兔牙本质磷酸蛋白（Dentin phosphoproteins,DPP）的稳定性机制。方法：通过钙离子沉淀法从兔切牙牙本质非胶原蛋白（Dentin non-collagenous proteins,NCP）中提取DPP，并应用凝胶过滤及离子交换层析技术纯化磷酸蛋白，同时观察多种蛋白酶抑制剂对DPP降解的抑制作用。结果：钙离子能够启动DPP的降解系统，而该作用可被巯基蛋白酶抑制剂N－顺丁烯二酰亚胺（NEM）抑制，从而阻止DPP分解。结论：提示NCPs中可能存在钙离子依赖性蛋白水解酶体系。     

腰椎退行性疾病手术患者椎间盘退变及责任间隙分布情况研究

背景　椎间盘退变是一系列腰椎退行性疾病的始动因素,既往研究多集中于腰椎间盘退变的流行病学及影像学研究方面,而关于严重腰腿痛的腰椎退行性疾病患者需手术干预的研究少见,其椎间盘退变分布规律并不明确,而责任间隙（手术节段）退变分布情况鲜有报道。目的　分析腰椎退行性疾病手术患者椎间盘退变及责任间隙分布规律。方法　选择2012年1月-2016年2月于中国人民解放军第960医院行腰椎正侧位、过伸过屈位X线和腰椎矢状位MRI检查并确诊为腰椎退行性疾病患者503例,分析腰椎间盘退变及责任间隙分布特点〔包括腰椎失稳、Modic改变、高信号区域（HIZ）、许莫结节（SN）〕;椎间盘退变分级采用Pfirrmann分级标准,Ⅰ、Ⅱ级为正常椎间盘,Ⅲ、Ⅳ、Ⅴ级为退变椎间盘（其中Ⅳ级、Ⅴ级为严重退变）;多间隙椎间盘退变采用自定义W分级标准,即两个及以上节段椎间盘退变程度。结果　503例患者共2 515个腰椎间盘,退变率为74.08%（1 863/2 515）,严重退变率36.46%（917/2 515）。上腰椎椎间盘（L1~2、L2~3）退变率为56.96%（573/1 006）,严重退变率为34.55%（198/573）;下腰椎椎间盘（L3~4、L4~5、L5~S1）退变率为85.49%（1 290/1 509）,严重退变率为55.74%（719/1 290）。下腰椎椎间盘退变率、严重退变率均高于上腰椎（P<0.05）。≥40岁女性腰椎间盘退变率高于男性（P<0.05）。<40岁男性腰椎失稳发生率与女性比较,差异无统计学意义（P>0.05）;而Modic改变、HIZ、SN发生率两性别间比较,差异均有统计学意义（P<0.05）。≥40岁女性腰椎失稳发生率高于男性（P<0.05）;而Modic改变、HIZ、SN发生率两性别间比较,差异均无统计学意义（P>0.05）。≥40岁男性Modic改变、HIZ与女性腰椎失稳、HIZ、SN与<40岁者发生率比较,差异均有统计学意义（P<0.05）。腰椎失稳、Modic改变、SN和HIZ腰椎退变节段分布情况比较,差异均有统计学意义（P<0.01）。手术节段单间隙381例,两间隙102例,三间隙14例,四间隙4例,五间隙2例;责任间隙椎间盘退变率为99.01%（498/503）,严重退变率为62.82%（316/503）。结论　腰椎退行性疾病手术患者的椎间盘退变率较高,且女性较高,下腰椎椎间盘高于上腰椎椎间盘,女性腰椎失稳、Modic改变发生率均高于男性,SN发生率低于男性,40岁是男性Modic改变及HIZ发生的转折点,也是女性腰椎失稳、HIZ、SN发生的转折点。责任间隙椎间盘大部分发生退变,且严重退变率较高。     

The lumbar intervertebral disc: From embryonic development to degeneration

Lumbar intervertebral discs (IVDs) are prone to degeneration upon skeletal maturity. In fact, this process could explain approximately 40% of the cases of low back pain in humans. Despite the efficiency of pain-relieving treatments, the scientific community seeks to develop innovative therapeutic approaches that might limit the use of invasive surgical procedures (e.g., spine fusion and arthroplasty). As a prerequisite to the development of these strategies, we must improve our fundamental knowledge regarding IVD pathophysiology. Recently, several studies have demonstrated that there is a singular phenotype associated with Nucleus pulposus (NP) cells, which is distinct from that of articular chondrocytes. In parallel, recent studies concerning the origin and development of NP cells, as well as their role in intervertebral tissue homeostasis, have yielded new insights into the complex mechanisms involved in disc degeneration. This review summarizes our current understanding of IVD physiology and the complex cell-mediated processes that contribute to IVD degeneration. Collectively, these recent advances could inspire the scientific community to explore new biotherapeutic strategies.     

Effect of radiofrequency microtenotomy on degeneration of tendons: An experimental study on rabbits

IntroductionRadiofrequency microtenotomy is used to enhance healing by increasing vascularity in the degenerated tendon. In the present study, the effect of radiofrequency microtenotomy (Rf-mt) treatment on tendon degeneration was investigated.Materials and methodsA total of 32 New Zealand rabbits were enrolled in the current study. Experimental degeneration was performed by injecting prostaglandin E1 (PGE1) into the bilateral Achilles tendons of rabbits. After excluding 4 rabbits with an infection on the injection site, 4 other rabbits were sacrificed to define the histopathologic changes in the tendons. The remaining 24 rabbits were divided into 2 groups: the control group and the Rf-mt group. In the control group, the Rf-mt device was only applied to the Achilles tendon without running the device. In the Rf-mt group, the Rf-mt device was applied bilaterally at the fourth energy level for 500 ms to an area within 2 cm proximal to the insertion site at 0.5 cm intervals in order to form a grid. Six rabbits from each group were sacrificed at 6 and 12 weeks. The Achilles tendons were evaluated histopathologically by a modified Movin scale and by immunohistopathologic staining for vascular endothelial growth factor and type 4 collagen.ResultsAfter the PGE1 injection, findings similar to chronic degenerative tendinopathy were observed. The Rf-mt group showed significant improvement in vascularity in the histopathological and immunohistochemical examination (P < 0.05). However, there was no significant difference in healing between the control and Rf-mt groups (P > 0.05).ConclusionsRf-mt treatment increases vascularity in degenerated tendons but does not create difference to facilitate the healing process comparing control group.     

腰椎体退变与血液供应减少相关：基于一项双期增强CT研究

目的观察腰椎血液供应随老龄化发生的变化,分析其对腰椎退变的影响。方法横截面研究。研究对象为2012年1月~2012年12月间来我院体检的正常人,随机抽取180例不同年龄段对象。采用Siemens Somatom Definition AS 4D CT进行腰3椎平扫及双期增强扫描,三维薄层重建腰3椎体平扫及双期增强矢状面图像,选择正中矢状面为兴趣区层面,观察腰3椎体CT平扫骨质密度、增强动脉期和血池平衡期对比剂密度在不同性别间以及不同年龄组间的差异及相互间的关系。结果男性组腰3椎体CT增强动脉期对比剂密度与平扫骨质密度呈正直线相关(r=0.420,P0.01),与年龄呈负相关性(r=-0.674,P0.01),血池平衡期对比剂密度与年龄呈正相关性(r=0.685,P0.01)。女性组腰3椎体CT增强动脉期对比剂密度与平扫骨质密度呈正直线相关(r=0.296,P0.01),与年龄呈负相关性(r=-0.448,P0.01),血池平衡期对比剂密度与年龄呈正相关性(r=0.752,P0.01)。结论腰椎体退变与血液供应减少相关,两者互为影响、形成不良循环。     

The biomechanical influence of anterior vertebral body osteophytes on the lumbar spine: A finite element study

BACKGROUND CONTEXT

Anterior vertebral body osteophytes are common with degeneration but their biomechanical influence on the whole lumbar spine remains unclear.