Ankylosing spondylitis (AS) combined with spinal fractures with thoracic and lumbar fracture as the most common type shows characteristics of unstable fracture, high incidence of nerve injury, high mortality and high disability rate. The diagnosis may be missed because it is mostly caused by low-energy injury, when spinal rigidity and osteoporosis have a great impact on the accuracy of imaging examination. At the same time, the treatment choices are controversial, with no relevant specifications. Non-operative treatments can easily lead to bone nonunion, pseudoarthrosis and delayed nerve injury, while surgeries may be failed due to internal fixation failure. At present, there are no evidence-based guidelines for the diagnosis and treatment of AS combined with thoracic and lumbar fracture. In this context, the Spinal Trauma Academic Group of Orthopedics Branch of Chinese Medical Doctor Association organized experts to formulate the Clinical guideline for the diagnosis and treatment of adult ankylosing spondylitis combined with thoracolumbar fracture ( version 2023) by following the principles of evidence-based medicine and systematically review related literatures. Ten recommendations on the diagnosis, imaging evaluation, classification and treatment of AS combined with thoracic and lumbar fracture were put forward, aiming to standardize the clinical diagnosis and treatment of such disorder.

The acute combination fractures of the atlas and axis in adults have a higher rate of neurological injury and early death compared with atlas or axial fractures alone. Currently, the diagnosis and treatment choices of acute combination fractures of the atlas and axis in adults are controversial because of the lack of standards for implementation. Non-operative treatments have a high incidence of bone nonunion and complications, while surgeries may easily lead to the injury of the vertebral artery, spinal cord and nerve root. At present, there are no evidence-based Chinese guidelines for the diagnosis and treatment of acute combination fractures of the atlas and axis in adults. To provide orthopedic surgeons with the most up-to-date and effective information in treating acute combination fractures of the atlas and axis in adults, the Spinal Trauma Group of Orthopedic Branch of Chinese Medical Doctor Association organized experts in the field of spinal trauma to develop the Evidence-based guideline for clinical diagnosis and treatment of acute combination fractures of the atlas and axis in adults ( version 2023) by referring to the "Management of acute combination fractures of the atlas and axis in adults" published by American Association of Neurological Surgeons (AANS)/Congress of Neurological Surgeons (CNS) in 2013 and the relevant Chinese and English literatures. Ten recommendations were made concerning the radiological diagnosis, stability judgment, treatment rules, treatment options and complications based on medical evidence, aiming to provide a reference for the diagnosis and treatment of acute combination fractures of the atlas and axis in adults.

目的:观察经皮椎弓根钉内固定治疗胸腰椎骨折的临床疗效及对应激反应的影响。方法:回顾性选取67例胸腰椎骨折患者，根据术式分为对照组30例和观察组37例，对照组予开放椎弓根钉内固定，观察组予微创经皮椎弓根内固定。比较两组手术情况(手术时间、术中出血量、住院时间)、VAS评分、ODI评分，行影像学检查(椎体高度、Cobb角)，测定应激反应指标(肌酸激酶、肾上腺素、皮质醇、C-肽)，记录并发症发生情况。结果:术后两组VAS评分、ODI评分、Cobb角显著降低，椎体高度和血清肾上腺素、皮质醇、肌酸激酶含量显著增加(均 P<0.05)。与对照组相比，观察组VAS评分、ODI评分、血清肾上腺素、肌酸激酶含量均较低(均 P<0.05)；手术时间、术中出血量、住院时间明显较少(均 P<0.05)。观察组并发症发生率为5.4%，低于对照组的23.3%( P<0.05)。 结论:微创经皮椎弓根钉内固定适于治疗胸腰椎骨折。

目的:对比分析Hoist内固定系统与常规内固定系统治疗腰椎峡部裂伴轻度滑脱的疗效.方法:回顾性分析2018年12月～2020年12月于我院明确诊断为腰椎峡部裂滑脱、Meyerding分级为I度或II度(轻度)滑脱患者的病例资料.根据内固定类型分为两组,A组采用Hoist内固定系统(撑开提拉复位系统);B组为常规钉棒内固定系统.共收集38例患者,其中A组18例,B组20例.比较两组手术时长、出血量、术后引流量、影像学检查所得的滑脱率、滑脱角、椎间隙高度、腰椎前凸角、疼痛视觉模拟评分(visual analogue scale,VAS)、Oswestry 功能障碍指数(Oswestry disability index,ODI)、日本骨科学会(Japanese Orthopaedic Association,JO A)评分等数据,评价两组的临床疗效.结果:38例患者均手术顺利,两组患者性别、年龄、患病时长、责任节段、滑脱分级、术前滑脱率及术前合并症等参数无统计学差异(P＞0.05).两组患者在术中出血量、术后引流量等指标上无统计学差异(P＞0.05),A组手术时间少于B组(160.8±15.3min vs 184.6±26.9min,P＜0.01).两组术后滑脱率明显小于术前,滑脱角、椎间隙高度及腰椎前凸角均大于术前(P＜0.01),但术前术后不同时间点两组滑脱率、滑脱角、椎间隙高度、腰椎前凸角等指标无统计学差异(P＞0.05).两组术后VAS、ODI均明显小于术前(P＜0.01),JOA评分均高于术前(P＜0.05),两组不同时间点VAS、JOA评分无统计学差异(P＞0.05),但术后6个月、12 个月时 A 组的 ODI(％)低于 B 组(18.1±3.2 vs 21.4±2.4;15.2±1.5 vs 16.8±2.0)(P＜0.01).结论:对于 Ⅰ、Ⅱ 度峡部裂腰椎滑脱患者,应用Hoist内固定系统、常规钉棒内固定系统均有助于帮助患者复位滑脱椎体,重建腰椎功能,获取终末椎间骨性融合,明显改善患者腰椎功能;Hoist内固定系统有助于缩短手术时间.

Objective:To compare the effects of Dynesys dynamic fixation and fusion fixation on the sagittal parameters of lumbar degenerative diseases of 2-4 segments.Methods:A total of 45 patients with 2-4 segments lumbar degenerative diseases, who underwent decompression and internal fixation in our hospital from March 2014 to July 2019, were retrospectively analyzed. There were 23 males and 22 females with an average age of 55±18 years (range 15-86 years). Dynesys dynamic fixation was performed in 22 cases and fusion fixation in 23 cases. Lumbar anteroposterior, flexion and extension lateral and standing full-length spine radiographs were taken before surgery, 2 weeks postoperatively, 3 months postoperatively and at the last follow-up. Sagittal alignment parameters were measured on those radiographs and compared between two groups. Lumbar parameters included lumbar lordosis (LL), lordosis of the fixed segments (LFx), lordosis of the adjacent level to fixed segment (LAdj) and lumbar range of motion (ROM). Pelvic parameters included pelvic incidence (PI), pelvic tilt (PT) and sacral slope (SS).Results:All cases were followed up for 12-50 months with an average of 18.5 months. There was no significant intra- and inter-group difference of LL value between Dynesys dynamic fixation and fusion fixation group before and after surgery ( P>0.05). The overall difference of LFx between groups was not statistically significant ( F=0.700, P=0.406). There was statistically significant variance between time points ( F=7.960, P<0.001) and an interaction effect between group and time ( F=3.940, P=0.006). The LFx of the fusion fixation group was more than that of the dynamic fixation group at 3 months postoperatively and at the last follow-up ( P<0.05). The difference of LAdj value between the two groups was not statistically significant ( F=0.520, P=0.476), while the difference between time points was significant ( F=4.810, P=0.002) with interaction effect between group and time ( F=3.560, P=0.010). Postoperative ROM values of the two groups showed statistically significant differences in group effect, time effect and interaction effect, respectively ( F=4.770, P=0.034; F=18.510, P<0.001; F=5.940, P=0.002). Dynamic fixation group's ROM was more than that of the fusion fixation group at 3 months postoperatively and at the last follow-up ( P<0.05). There was no significant difference of PI between groups and between different time points ( F=0.580, P=0.451; F=0.750; P=0.477). There was no interaction effect in PI between group and time ( F=0.120, P=0.886). There was no significant difference of PT and SS between two groups ( F=0.320, P=0.576; F=0.020, P=0.901). Both time effect and interaction effect were statistically significant ( P<0.05). One complication of unilateral S 1 screw loosening happened in one patient with dynamic fixed at 2 years after surgery. There was no complication in the fusion fixation group during the follow-up. Conclusion:Both Dynesys dynamic fixation and fusion fixation can effectively reconstruct the lumbar lordosis. The fixed segments' lordosis of Dynesys was less than that of fusion fixation from 3 months after operation. Theoretically, the similar increasing trends of LAdj after fixation implied that the degeneration of adjacent segments may occur in both fixation systems. The dynamic fixation can retain more ROM than the fusion fixation. Both two fixation systems have similar influence on the pelvic parameters.

目的 探讨基于腰椎MRI影像的椎体骨质量(vertebral bone quality,VBQ)分数在腰椎内固定术前骨量评估中的作用.方法 回顾性分析2018年1月至2021年1月因腰椎退变性疾病在解放军总医院第四医学中心行腰椎内固定手术治疗的99例患者的临床资料.根据双能X线骨密度仪获得的股骨颈T值,将患者分为正常骨密度组(24例)和低骨密度组(75例),比较两组患者的一般情况、股骨颈T值及基于腰椎MRI T1加权像的VBQ分数,分析VBQ分数与股骨颈T值的关系及其预测低骨密度的准确率.结果 两组患者的年龄、性别、体重指数、吸烟史、长期(超过3个月)应用激素史、糖尿病史、高血压史差异均无显著性(P>0.05).低骨密度组的VBQ分数(3.03±0.40)显著高于正常骨密度组(2.54±0.24),差异有显著性(P=0.001).VBQ分数与股骨颈T值呈中度正相关(r=0.45,P=0.01),而其预测低骨密度的准确率为86％.结论 基于腰椎MRI的VBQ分数在腰椎融合内固定术前能较好地识别骨量下降,可作为术前缺乏骨密度值时的一种机会性筛查指标.

临床上接受手术治疗的退行性脊柱畸形患者数量逐年增多.其原因主要在于两方面:首先从患者角度讲,随着老龄化社会的到来和人们对生活质量的更高要求,越来越多的老年患者要求通过积极治疗实现腰背痛以及下肢神经痛的改善;其次从医生角度讲,更多的训练有素的脊柱外科医生有能力通过手术的方式帮助患者解决困扰他们的脊柱畸形带来的相关症状 [1].

目的:探讨退变性脊柱侧凸患者长节段固定矫形融合术后冠状面失平衡的相关危险因素.方法:回顾性分析2014年1月～2017年2月在我院行长节段固定矫形融合术并具有完整影像学及随访资料的61例退变性脊柱侧凸患者.男24例,女37例;年龄53～78岁(59.0±6.1岁);按鼓楼医院退变性脊柱侧凸分型:A型31例,B型19例,C型11例.固定融合范围:T10～L518例,T10～S16例,T10～S26例,T12～L514例,L1～L58例,L1～S17例,L2～S12例.随访18～85个月(平均36.4个月),根据末次随访时冠状面平衡情况将其分为平衡组和失平衡组,比较两组术前和末次随访时的主弯Cobb角、冠状平衡距离(CBD)、畸形矫正率和术前L5倾斜度、畸形分型、腰弯顶椎位置、顶椎旋转度、截骨级别、固定节段及数量、远端固定椎、腰骶弯Cobb角、主弯Cobb角与腰骶弯Cobb角比值等,将具有统计学差异的指标进行二元Logistic回归分析.结果:61例患者中,末次随访时8例出现冠状面失平衡加重或新发失平衡.两组患者术前主弯Cobb角、CBD、顶椎旋转度、腰弯顶椎位置、截骨级别、固定节段及数量、远端固定椎无统计学差异(P＞0.05),术前腰骶弯Cobb角、术前主弯Cobb角与腰骶弯Cobb角比值、术前L5倾斜角、术后主弯Cobb角、术后CBD、畸形矫正率及畸形分型有统计学差异(P＜0.05).二元逻辑回归分析显示术后冠状面失平衡与术前主弯Cobb角、术前腰骶弯Cobb角、术前L5倾斜度呈正相关,OR值分别为1.158、1.210、1.322(P＜0.05),与畸形矫正率、顶椎旋转度、固定节段数量无显著相关性(P＞0.05).结论:退变性脊柱侧凸长节段固定矫形融合术后可出现冠状面失平衡,术前主弯及腰骶弯Cobb角较大、L5倾斜角较大是退变性脊柱侧凸术后冠状面失平衡或原有失平衡加重的危险因素.

完整的脊柱结构是维持身体平衡与稳定、保护脊髓、缓冲外部震荡的重要保证.当人体遭遇巨大暴力,如车祸、坠落或地震灾害时,脊柱连续性发生变化,可发生椎体骨折、脱位或脊髓损伤 ( spinal cord injury,SCI ) 等.脊柱损伤较轻者表现为局部疼痛、活动受限等;严重者可出现不同程度的神经根损伤或 SCI.创伤性脊髓损伤 ( traumatic spinal cord injury,TSCI ),表现为截瘫平面以下感觉、运动丧失和膀胱 / 肠道功能障碍,同时给家庭和社会造成严重的经济负担 [1].在美国,急性 TSCI 累及 250000 人,每年大约增加 17000 例新发患者 [2].在亚洲,TSCI 的发病率为 ( 12.06～61.60 ) / 百万,尤其见于中国和韩国 [3].平均患病年龄为 26.8～56.6 岁.男性较女性更易受累.

椎间融合器(interbody fusion cage)联合椎弓根钉棒系统实施腰椎后路减压融合内固定术是治疗腰椎退变性疾病如腰椎管狭窄症、腰椎滑脱症、腰椎间盘突出症合并腰椎不稳等的常用手术方法,包括后路腰椎椎间融合术(posterior lumbar interbody fusion,PLIF)和经椎间孔入路腰椎椎间融合术(trans-foraminal interbody fusion,TLIF),取得了良好的效果.但是有0.9％～4.7％的腰椎后路手术患者由于椎间融合器应用不规范,术后出现椎间融合器相关并发症,给后续治疗带来困难[1～5].为了正确规范地应用椎间融合器,减少椎间融合器相关并发症的发生,《中国脊柱脊髓杂志》编辑部组织的国脊沙龙邀请20余位脊柱外科专家,在循证医学的基础上,经多轮专家讨论,形成以下共识,供脊柱外科医师参考.

目的 探讨不同处理方法 对同种异体肌腱生物学性能的影响,并筛选最佳处理方法.方法应用四种处理方法:1％TnBP+1％Triton X-100(A组)、0.5％胰蛋白酶+0.5％Triton X-100(B组)、1％TnBP(C组)、1％Triton X-100+70％异丙醇(D组)分别对新鲜肌腱进行处理,组织学染色观察去细胞效果;CCK8法检测细胞毒性;扫描电镜观察细胞黏附情况;皮内刺激实验评价体内相容性.结果 采用0.5％胰蛋白酶+0.5％Triton X-100去除细胞最彻底,纤维排列整齐,结构完整,其它组均观察到有少部分细胞残留;CCK8结果显示,A组和C组处理的肌腱为二级细胞毒性,B组和D组处理的肌腱为1级细胞毒性.扫描电镜结果显示A组和C组处理的肌腱上细胞黏附数量较少,且基本呈圆形;D组处理的肌腱上细胞黏附数量较多,细胞状态较好;B组处理的肌腱上细胞黏附数量最多,细胞成片生长,状态较好.皮内刺激实验结果显示,各组均出现红肿和焦痂.结论 在四种肌腱处理方法中,0.5％胰蛋白酶+0.5％Triton X-100的处理方法最为理想.

退变性脊柱侧凸常见于老年患者,通常合并高血压病、冠心病、糖尿病和骨质疏松等基础疾病,手术风险高、并发症多.加速康复外科(ERAS)要求综合考量患者的年龄、症状、体征、身体状况和骨质量等因素,以制定个体化的手术方案和围手术期干预措施,这对改善患者预后和康复十分重要.经全国多位脊柱外科专家多次讨论,在循证医学证据支持下,针对退变性脊柱侧凸手术ERAS围手术期管理策略制定本共识意见,供临床工作参考和应用.

目的 初步探索3D打印技术在脊柱畸形领域研究生教学中的应用.方法 选取2018年在解放军医学院就读的外科硕士研究生共52名作为研究对象,在进行脊柱畸形小班课教学时随机将学生分为传统教学组和3D打印教学组.传统教学组依照教学大纲进行传统教学方法教学,3D打印教学组在传统教学基础上利用3D打印模型更加直观强化对疾病的认识,加深理解和记忆.在课程结束后和1年后分别进行相关知识测试.结果 与传统教学组相比,3D打印教学组在课程结束学年测试平均分78.3±7.7,总体高于传统教学组的75.1±8.0,但差异无统计学意义(t=0.921,P>0.05),1年后3D打印教学组测试评分70±8.9,高于传统教学组评分61±10.8,差异有统计学意义(t=2.369,P<0.05).结论 3D打印辅助教学模式在引入较为抽象的脊柱畸形教学实践中,能够使研究生更好地掌握相关教学内容,特别是有利于形成较好的长时记忆.

[目的]介绍多棒技术翻修胸腰椎骨折初次术后断棒.[方法] 2017年3月～2018年9月运用多棒技术行胸腰椎骨折术后断棒翻修的患者11例,沿原切口暴露断棒侧内固定物,拆除断棒后如果发现螺钉松动予以更换,必要时行伤椎置钉.于内侧置入卫星棒,分别用连接器与原始固定棒或更换后的棒相连,而且头尾侧需要各跨越至少1个节段,以形成坚强稳固的内固定,最后植骨及关闭切口.[结果]11例患者均顺利进行翻修手术,无严重并发症.末次随访时VAS和ODI评分均较术前显著减少,矢状位局部Cobb角由翻修术前(9.89±3.19)°,改善至末次随访时(-1.68±5.82)°.[结论]胸腰椎骨折术后断棒采用多棒技术翻修安全、简单,疗效显著.

自2019年12月以来,已有200余个国家和地区相继报道了新型冠状病毒感染病例,世界卫生组织(WHO)于2020年3月12日宣布新型冠状病毒全球大流行,截至6月18日,全球已累计有824万余人感染,44万余人死亡,对全世界医疗、政治和经济领域影响巨大[1-2].WHO将其命名为"2019冠状病毒感染性疾病"(COVID-19),病原体被命名为重症急性呼吸综合征冠状病毒2(SARS-CoV-2)[3-6].

目的 观察运动机能贴布结合maitland手法治疗IIB型三角纤维软骨复合体(triangular fibrocartilage complex,TFCC)损伤的临床疗效.方法 纳入2016年6月至2018年12月,我院门诊收治的50例IIB型TFCC损伤病程少于7天的患者,采用随机数字表法将其分为试验组1和试验组2,其中25例采用maitland手法作为试验组1,另外25例采用运动机能贴布结合maitland手法治疗作为试验组2,每组患者在治疗前及治疗后分别采用疼痛视觉模拟评分(visual analogue scale,VAS),Cooney腕关节功能评分法进行分析和比较,治疗时间2周.结果 治疗后2周,两组的患者的VAS及Cooney腕关节功能评分有显著改善(P<0.05),VAS评分:治疗前试验组1(7.03±1.54),试验组2(7.06±1.48),治疗后试验组1(3.25±0.85),试验组2(1.91±0.66);Cooney腕关节功能评分:治疗前试验组1(53.41±6.25)分,试验组2(52.40±7.32)分,治疗后试验组1(83.76±8.96),试验组2(91.15±8.13).VAS评分治疗后试验组2的低于试验组1(P<0.05),试验组2的Cooney腕关节功能评分高于试验组1(P<0.05).结论 针对病程少于7天的IIB型TFCC患者,单纯的maitland手法或运动机能贴布结合maitland手法均能改善患者的疼痛和腕关节功能,但运动机能贴布结合maitland手法能明显缓解疼痛,改善腕关节活动范围及提高腕关节功能.

目的 探讨脱钙骨基质(decalcified bone matrix,DBM)和煅烧骨复合BMP-2两种骨诱导材料用于修复兔股骨髁缺损的效能差异.方法 构建双侧兔股骨髁缺损动物模型,分别植入DBM(实验侧)和煅烧骨/BMP-2复合物(对照侧);4周后取样,从大体形态学和组织学观察成骨情况.结果 大体形态学观察显示,煅烧骨/BMP-2材料完全覆盖缺损区域,与周围骨组织连结紧密,单纯DBM材料未能完全覆盖骨缺损区域,材料与骨组织结合欠佳,边缘尚留有空隙.组织染色后可见煅烧骨/BMP-2材料填充于直径0.4 cm的圆形缺损区域内,材料周围均有大量新骨形成,材料与新生骨交织成片覆盖整个缺损区域,可见大量的骨陷窝和骨细胞及部分骨小梁形成,未见炎症细胞及新的血管形成.而单纯DBM组可见大量成片的DBM将缺损中央区域填满,仅在部分材料的边缘区域见到少量成条索状的新骨形成.结论 DBM在早期兔股骨髁部位成骨能力较弱,煅烧骨/BMP-2对股骨髁缺损的修复能力更为显著.

目的 探讨亚临床性甲状腺功能减退症(subclinical hypothyroidism,SCH)对妊娠结局的影响及甲状腺激素替代疗法的临床疗效.方法 选取2015年1月至2018年12月解放军总医院第五医学中心收治的216例SCH孕妇为研究对象,按照治疗方案将其分为高剂量组(高剂量左旋甲状腺素替代治疗,108例)和低剂量组(低剂量左旋甲状腺素替代治疗,108例),随机选取该院同期108例健康孕妇纳入健康组,比较三组孕妇不良妊娠结局、新生儿情况及新生儿甲状腺功能.结果 高剂量组和健康组孕妇的流产率、早产率及新生儿血清促甲状腺激素(thyroid-stimulating hormone,TSH)水平均显著低于低剂量组(P均<0.05).三组新生儿低出生体重率、新生儿畸形率、Apgar评分、血清游离三碘甲腺原氨酸和游离甲状腺素水平均无显著差异(P均>0.05).结论 SCH可增加孕妇流产、早产等不良妊娠结局的发生风险,并对新生儿TSH水平产生影响.甲状腺激素替代治疗可有效改善SCH孕妇的妊娠结局,临床可加强孕妇早期TSH筛查并给予药物干预措施,保障母婴健康.

BACKGROUND: A proper virus inactivation procedure of medical bio-derived tissue repair material is very important to reduce the risk of virus infection and ensure the safety in the therapeutic process. OBJECTIVE: To elaborate different virus inactivation methods of allogeneic and xenogeneic tissue repair materials. METHODS: PubMed, Elsevier, CNKI, and WanFang databases were searched for relevant articles using the keywords of "allogeneic, xenogeneic, viral inactivation, disinfection, tissue repair biomaterial" in English and Chinese, respectively. RESULTS AND CONCLUSION: Virus inactivation methods can damage the performance of biological materials to different extents. For example, heat inactivation may produce permanent damage to the performance of heat-sensitive materials; γ-ray irradiation may result in the loss of mechanical properties and biologically active substances; acid/alkali method may also destroy the properties and structure of some materials intolerant to acid and alkali corrosion; and some reagent residues such as ethylene oxide, peracetic acid, and hydrogen peroxide may produce irritation to the body and even cause carcinogenic and teratogenic substances. Therefore, in enterprises and research institutions, the virus-killing effect and severity of damage to the material performance should be considered when the virus inactivation process is selected, and the use of existing production processes to verify the virus inactivation is recommended as much as possible.

Objectives:To explore the effects of hypoxia mimic agent dimethyloxalylglycine(DMOG) on the proliferation,osteogenic differentiation and vascular endothelial growth factor(VEGF) expression of MC3T3-E1 cell.Methods:After MC3T3-E1 cells were seeded on plate for 24 hours,DMOG was added to the culture medium with concentrations of 50μM(50μM group) and 200μM(200μ M group) respectively,while in the control group no DMOG was added.The proliferation of MC3T3-E1 cells was detected by MTT assay at the 1st,3rd and 5th day of cells culture.The osteoblast differentiation was determined by alkaline phosphatase activity analysis and ALP staining at the 5th and 10th day.The formation of calcium nodules in MC3T3-E1 cells was detected by alizarin red staining and quantitative analysis at the 21st day.The level of VEGF in the su pernatant of MC3T3-E1 cells was detected by ELISA method,and the gene expression of VEGF was also detected by real-time fluorescence quantitative PCR.Results:At the 1st day of cells culture,the values of light density (optical density,OD) in the control group,the 50μM group and the 200μM group were 0.041± 0.009,0.074 ±0.019,and 0.086±0.044 respectively.At the 3rd day,the values of OD in the control group,the 50μM group,and the 200μ M group were 0.123±0.027,0.148±0.020,0.224±0.061 respectively.At the 5th day,the values of OD in the control group,the 50μ M group and the 200μM group were 0.297±0.044,0.325±0.084,0.354±0.038 respectively.At the 1st day and the 3rd day,the DMOG results of the 50μM and 200μM group were significantly different from that of the control group(P＜0.05).At the 3rd day,the DMOG result of 50μ M group was significantly different from that of 200μM group.ALP staining showed that the color was deeper in the control group,moderate in the 50μM group,and shallow in the 200μM group.At the 5th day,the alkaline phosphatase activity was 1.943 ±0.072 in the control group,1.632±0).051 in the 50μM group,1.319±0.065 in the 200μM group.At the 10th day,the alkaline phosphatase activity was 3.734±0.067 in the control group,3.381±0.070 in the 50μM group,2.831±0.086 in the 200μM group.Alkaline phosphatase activity was significantly different between each two groups(P＜0.05).Alizarin red staining and quantitative analysis showed a small amount of red nodules in the 200μM group,a moderate amount red nodules in the 50μM group,while a large number of red nodules in the control group.The alizarin red content was 56.178 ±7.940 in the control group,41.922±2.438 in the 50μ M group,31.929±1.922 in the 200μM group.There was significant difference of alizarin red content(μg/ml) between each two groups(P＜0.05).The VEGF content in the supernatant was 9.063 ±0.603 in the control group,12.123±0.870 in the 50μM group,15.540±0.581 in the 200μM group.There was significant difference of VEGF content between each two groups(P＜0.05).The VEGF gene expression level was 1.792±0.067 in the 50μ M group,3.963±0.092 in the 200μ M group,and there was significant difference of VEGF gene expression level between each two groups(P＜0.05).Conclusions:Under normal oxygen condition,hypoxia mimicking agent DMOG significantly promotes proliferation and VEGF expression,while inhibites osteogenic diferenfiation in MC3T3-E1 cell.