可注射型生物蛋白胶包埋骨髓基质细胞工程化组织的体外实验

目的构建可注射型生物蛋白胶包埋骨髓基质细胞的工程化组织,体外培养并研究其生物学特性,探讨将可注射型生物蛋白胶作为组织工程支架用于临床的实验基础。方法体外培养浇铸有骨髓基质细胞的生物蛋白胶,通过倒置相差显微镜、激光共聚焦显微镜观察载体内细胞生长及载体降解情况,5-溴脱氧尿苷(5-Bromodeocyuridine,BrdU)掺入标记后免疫组化等方法研究可注射型载体内包埋细胞的增殖情况。结果骨髓基质细胞包埋于生物蛋白胶内能很好地存活并增殖,2d后细胞呈典型的成纤维细胞形态;6d后生物蛋白胶边缘部分开始降解,细胞脱落至培养板;体外培养14d,细胞生长良好,大部分生物胶降解,脱落的细胞增多,贴壁生长的细胞形态正常;3周后生物蛋白胶完全降解。结论生物蛋白胶聚合后包埋的种子细胞能够正常增殖,生物蛋白胶是一种理想的适用于微创方法修复组织的可注射型组织工程培养和移植的支架。     

股骨粗隆部骨折内固定失败原因分析

目的：总结分析股骨粗隆部骨折髓内和髓外固定失败发生的原因并提出预防措施。方法：对2005年5月至2009年6月北京大学第三医院连续收治的256例股骨粗隆部骨折患者采用回顾性分析,收集患者临床资料并采用电话或门诊随访,利用SPSS 13.0软件通过单因素及多因素Logistic回归,分析患者年龄、性别、骨折类型、骨骼质量、内固定种类、术后颈干角和Garden指数以及开始负重时间对内固定失败的影响,结合临床实践总结内固定失败的主要原因。结果：术后发生螺钉穿出、螺钉切出、螺钉断裂、骨折不愈合共10例,失败率5.15%。术后开始负重时间为内固定失败的危险因素（P<0.001）,而年龄、性别、骨骼质量、骨折类型、内固定种类、术后颈干角和Garden指数与内固定失败无明显相关性（P>0.05）。结论：患者术后开始负重时间是内固定失败的危险因素,负重时间的选择应该根据患者的个体情况,如骨骼质量、骨折类型来确定。骨折类型>2.2型,Singh指数≤3,即使内固定位置良好,开始负重时间也应该选择在术后2个月。     

医院开展医学大数据应用初探

阐述医院医学大数据的来源、特点以及在医学研究实践中的主要应用,指出医院医学大数据应用场景广泛,但同时面临众多问题与挑战,以期为医院医学大数据应用提供借鉴。     

肩袖损伤修补金属锚钉置入角度——有限元分析

目的通过有限元分析方法比较肩袖修补术中冈上肌肌腱足印区处以90°、45°置入金属锚钉时钉体及周围骨组织的受力情况。 方法利用CT数据建立肱骨近端和锚钉的三维模型，在冈上肌肌腱止点足印区、肱骨大结节和关节软骨交接区模拟90°、45°置入锚钉，且加载15°、30°、45°、60°、75°、90°的100 N拉力，采用有限元分析软件ABAQUS模拟分析锚钉和肱骨近端骨组织应力分布情况。 结果在所有的模型中，锚钉的最大等效应力集中在锚钉下方小孔和近端螺纹之间。45°置入的锚钉周围骨组织的最大等效应力集中在近端锚钉螺纹和牵引侧的骨组织表面之间；而90°置入的锚钉周围骨组织等效应力比较均衡的分布在近端螺纹周围。以100 N的拉力从15°~75°对锚钉进行牵拉时，45°置入的锚钉所受的最大等效应力大于90°置入锚钉所受应力；随着角度的增大，两个角度置入锚钉之间应力差异逐渐减小。90°牵拉载荷时，90°置入的锚钉所受的应力稍大于45°置入锚钉所受应力。金属锚钉受从15°~90°牵拉载荷时，45°置入锚钉周围骨组织所受的最大等效应力均大于以90°置入锚钉周围骨组织的所受的最大等效应力。 结论有限元分析结果显示，以90°置入锚钉时锚钉及其周围骨组织所受的应力较45°置入锚钉更小，建议肩袖修补手术中采用90°置入锚钉。     

Effect of Single Versus Multiple Fractures on Systemic Bone Loss in Mice

Systemic bone loss after initial fracture contributes to an increased risk of secondary fracture. Clinical research has revealed an association between the risk of future fracture and the number or magnitude of prior fractures. However, the change in systemic bone mass after single versus multiple fractures is unknown. We used ipsilateral femur and tibia fractures as multiple fractures and a femur or tibia fracture as a single fracture to investigate the influence of single versus multiple fractures on systemic bone mass. Seventy-two adult male C57BL/6J mice underwent transverse osteotomies of the ipsilateral femur and/or tibia with subsequent internal fixation. The dynamic change of in vivo whole-body BMD was assessed at 4 days, 2 weeks, and 4 weeks after fracture. The microstructure of the L₅ vertebral body and contralateral femur was assessed using micro-CT (μCT) and biomechanical tests (vertebral compression test and three-point bending test) at 2 and 4 weeks. Tartrate-resistant acid phosphatase (TRAP) staining, sequential fluorescence labeling, and systemic inflammatory cytokines were also quantified. A greater decrease in whole-body BMD was observed after multiple than single fractures. The trabecular bone volume fraction, trabecular number, and trabecular thickness of the L₅ vertebral body were significantly reduced. There were no significant differences in cortical thickness, trabecular bone microstructure, or bone strength in the contralateral femur. At 4 days and 2 weeks, we observed significant increases in the serum levels of IL-6 and TNF-α. We also observed an increase in the osteoclast number of the L₅ vertebral body at 4 days. These data indicate that systemic bone loss might increase with the number or severity of prior fractures, and the mechanism may be partly associated with an increased osteoclast number and a more severe inflammatory response. © 2020 American Society for Bone and Mineral Research (ASBMR).     

Shear Wave Elastography in the Evaluation of Temporomandibular Joint Disorders

We aimed at verifying the usefulness of shear wave elastography in determining the temporomandibular disc stiffness in patients with a temporomandibular disorders (TMDs). The study included 37 patients with confirmed TMDs and 208 healthy volunteers. Patients presented with significantly greater stiffness of the intermediate zone of the disc (region of interest [ROI] 1) and significantly lower stiffness of its anteriorly displaced portion (ROI 3). A receiver operating characteristics analysis indicated that a decrease in the stiffness in ROI 3 less than 8.667 KPa provided 100% sensitivity, 97.3% specificity, 100% positive predictive value (PPV) and 99.5% negative predictive value (NPV) in distinguishing between patients with TMDs and without. Whereas an increase in ROI 1 stiffness to at least 54.33 KPa provided high specificity and NPV, both the sensitivity and the PPV of this predictor equaled zero. Findings suggest that a decrease in anteriorly dislocated disc stiffness less than 8.667 kPa can accurately identify patients with TMDs.     

胸椎黄韧带骨化症的影像诊断

目的:探讨胸椎黄韧带骨化症的诊断及影像学特点。方法:分析90例胸椎黄韧带骨化症患者的CT和/或MRI资料,并根据影像学特征进行分类。按照MRIT2WI轴位脊髓及硬膜囊的受压迫程度分为轻度、中度、重度。9例获CT或/和MRI检查2年以上随访的患者,选择扫描条件、部位一致的骨化节段对比研究其变化情况。结果:MRI扫描的73例患者共发现黄韧带骨化节段421个。骨化节段呈跳跃性分布35例(46.58%)。多节段发生68例(93.15%)。T2WI轴位扫描的365个节段呈现有压迫:轻度193个节段,中度80个节段,重度92个节段。9例2年以上影像随访患者,随访前CT示均匀性骨化的9个节段,随访时骨化块大小密度无变化;随访前不均匀性骨化6个节段,随访时骨化块增大、密度改变。随访前MRI示骨化为无信号9个节段,随访时骨化块的形态、内部信号、对脊髓的压迫程度均无改变;随访前低信号18个节段,随访时15个节段有不同程度的生长,即对脊髓和硬膜囊的压迫程度加重,骨化块形态改变,3个节段只有骨化块信号的改变,脊髓的受压程度无明显变化。结论:胸椎黄韧带骨化多数病例为多节段,分布无明显规律性。骨化程度与对脊髓的压迫程度并不一致。CT和MRI检查可以作为判断胸椎黄韧带骨化是否成熟的手段。     

Clinical characteristics and surgical outcomes of ependymomas in the upper cervical spinal cord: a single-center experience of 155 consecutive patients

Neurosurgical Review - Ependymomas occurring in the upper cervical spinal cord (above the level of the C4 segment) are rare entities with great therapeutic challenges. This study was aimed to...     

Manipulative therapy of sacral torsion versus myofascial release in patients clinically diagnosed posterior pelvic pain: a consort compliant randomized controlled trial

BACKGROUND CONTEXTChronic low back pain represents a health care problem with substantial costs. It is generally accepted that approximately 10% to 25% of patients with persistent chronic low back pain may have pain arising from the sacroiliac joints.PURPOSEThis study aimed to analyze the effects of manipulative therapy of sacral torsion versus myofascial release on disability, pain intensity, and mobility in patients with chronic low back pain and sacroiliac joints.STUDY DESIGN/SETTINGA prospective, single-blinded randomized clinical trial.PATIENT SAMPLESixty-four patients (mean±SD age: 51±9; 60% female) with chronic low back pain and sacroiliac joints comprised the patient sample. No participant withdrew because of adverse effects.OUTCOME MEASURESSelf-reported disability (primary), pain intensity, scale of kinesiophobia, quality of life, isometric endurance of trunk flexor muscles, and lumbar mobility in flexion were assessed at baseline, pos-treatment, and one month follow-up.METHODSParticipants were randomly assigned to a sacral torsion manipulation group or myofascial release group, receiving a total of 12 sessions (once weekly).RESULTSANCOVA did not showed a statistically significant difference between groups for disability (95% CI -2.40−1.90, p=.177). Effect sizes were large in both groups at both follow-up periods. Similar results were achieved for all secondary outcomes (p˂. 05). The linear model longitudinal analyses showed significant improvements in both groups over time for all outcomes with the exception of fear of movement (manipulative: Minimum within-groups change score 1.91, p˂.001; myofascial: 1.66, p˂.001).CONCLUSIONManipulative and myofascial release therapy in patients with clinically diagnosed sacroiliac joints syndrome resulted in a similar short-term benefits on patient reported disability. Both groups experienced similar decrease in the intensity of pain over time, although no clinically meaningful effects were demonstrated in either group.