目的 比较关节镜下不同固定方式(肩峰下间隙固定、结节间沟下固定)治疗肱二头肌长头肌腱炎的临床效果.方法 回顾性选取郑州大学第一附属医院运动医学科2016年7月至2020年7月收治的73例因肱二头肌长头肌腱炎行关节镜下肱二头肌长头腱切断固定术的患者,均获得随访.38例接受关节镜下肩峰下间隙固定(A组),35例接受关节镜下结节间沟下固定(B组).比较两组患者术前、术后1个月和术后末次随访时视觉模拟评分(VAS)、美国肩肘关节医师协会(ASES)评分、Constant肩关节评分、手术时间、术后大力水手征发生情况和肘关节屈曲力量等.结果 术前及术后末次随访时,两组VAS评分、Constant评分和ASES评分比较,差异无统计学意义(P＞0.05);与术前比较,两组患者术后1个月、术后末次随访时VAS评分降低,Constant评分和ASES评分升高(P＜0.05);术后1个月,B组VAS评分低于A组,Constant评分和ASES评分高于A组(P＜0.05).A组手术时间长于B组(P＜0.05).A组术后大力水手征发生情况与B组比较,差异无统计学意义(P＞0.05).与术前比较,两组术后末次随访时屈肘力量差异无统计学意义(P＞0.05),且两组患者术前、术后屈肘力量比较,差异无统计学意义(P＞0.05).结论 与关节镜下肩峰下间隙固定术相比,关节镜下结节间沟下固定术具有手术时间短、术后早期肩关节疼痛轻和功能改善迅速等优点,可临床推广.

[目的]比较聚醚醚酮(polyether ether ketone,PEEK)与钛合金材质挤压螺钉前交叉韧带(anterior cruciate ligament,ACL)重建术对移植物-骨愈合的影响.[方法]2017年10月—2019年10月,ACL损伤患者106例纳入本研究.将患者随机分为两组,各53例.均采用LARS人工韧带行ACL重建术,PEEK组采用PEEK螺钉,而钛合金组采用钛合金挤压螺钉固定移植物.比较两组临床、实验室检测和影像资料.[结果]两组患者均顺利完成手术.与术前相比,末次随访时两组患者的Lachman试验和轴移试验的稳定性均显著改善,Lysholm评分和膝伸屈ROM增显著增加(P＜0.05).PEEK组在Lachman试验和轴移试验的稳定性,以及Lysholm评分和膝伸屈ROM均显著优于钛合金组(P＜0.05).实验室检测方面,与术前相比,术后2个月两组的血浆白蛋白、球蛋白,血清补体C3、补体C4水平比较均无显著变化(P＞0.05).相应时间点,两组间血浆白蛋白、球蛋白,血清补体C3、补体C4水平的差异均无统计学意义(P＞0.05).影像方面,随术后时间推移,两组骨隧道扩大显著增加(P＜0.05),相应时间点PEEK组骨隧道扩大均显著小于钛合金组(P＜0.05).[结论]PEEK挤压螺钉具有良好的生物相容性和力学特性,更有利ACL重建移植物与骨的愈合.

Objective:To construct an adenovirus containing bone morphogenetic protein (BMP)-4 and use its characteristic of ectopic bone formation in skeletal muscle to explore the in vivo effect of transplanting heterotopic autologous bone for bone defect repair. Methods:The BMP4 gene was constructed into AAV vector, and AAV-BMP4 was purified. AAV-BMP4 was adsorbed in Gelfoam and implanted into the femoral muscle pocket of SCID mice raised in the SPF breeding room of the Experimental Animal Center of Zhengzhou University. The activity of AAV-BMP4 was determined 4 weeks post operation. Apply AAV-BMP4 subcutaneously on the back of the mouse to observe the skeletal muscle induced ectopic bone formation. While the bone tissue is stable, the bone tissue is taken out and transplanted into the pre-prepared mouse skull defect model to observe the bone defect repair effect.Results:The purified AAV-BMP-4 virus particles with a concentration of 5×10 12 vp/ml were successfully constructed. The purified AAV-BMP-4 virus particles implanted into the femoral muscle pocket of mice can successfully induce the formation of ectopic bone tissue. A small amount of new bone tissue appeared 4 weeks after the AAV-BMP-4+ Gelfoam complex was implanted subcutaneously on the back of the mouse with an amount of 1 cm×2 cm×2 cm. Both X-ray and MicroCT examinations confirmed the formation of subcutaneous bone tissue on the back of the mouse. The bone tissue that was trimmed and transplanted into the mouse skull defect model did not show abnormal proliferation after being implanted in the defect, but continued to undergo slight changes in appearance over time, and the skull defect was well repaired. Conclusion:The AAV-BMP-4 constructed in vitro has good biological activity. AAV-BMP-4+ Gelfoam can effectively induce bone formation in skeletal muscle. The new bone tissue can successfully repair the animal model of skull defect. After the transplanted bone tissue was implanted into the skull defect, there was no overgrowth, and it was well integrated with the host bone.

The fracture of the outer steel wire occurred during the use of a steel wire rope for an oil drilling.The fracture reasons were analyzed by means of macro fracture analysis,chemical composition analysis,mechanical property test,metallographic analysis and electron microscopic analysis.Results show that the wire rope broken wire is fatigue fracture;the wear damage caused by friction pulley wire rope used in contact with the outside is a major cause of wire rope fatigue fracture of the steel wire.The iron oxide inclusions exist in steel wire destroy the continuity of metal,also accelerated wire breakage.It is suggested that running strictly according to operation specification in use,strengthen steel wire raw material quality control in production,improve steel wire smelting purity.

A hybrid journal-thrust floating-ring bearing with independent oil supply for inner and outer fluid film was presented.The static characteristics parameters under different inner and outer oil supply pressure were calculated by Finite Element Method.The calculation results show that the friction power is not increased sharply and other static characteristics parameters are changed a little with the change of oil supply pressure.The results offer reference to analyze the dynamic characteristics and stability of hydrostatic/hybrid floating-ring bearing with independent oil supporting systems.

The structure of traditional inner flow-restriction mode is improved by reducing furthest the area of the restricting cave.When it is applied to a hydrostatic journal bearing,the improved inner flow-restriction mode can effectively avoid the blocking problem occurring often to the nor- real external restrictors and as well as increases the efficient area of the working cave so that the loading capacity and stiffness of a hydrostatic bearing are enhanced.This paper calculates the dimensionless loading capacities and dimensionless stiffness values of the hydrostatic journal bear- ing with above-mentioned improved throttling modein different restriction ratios and compares the results with the characteristic coefficients of the hydrostatic bearings with same working conditions but throttled respectively by the capillary restrictor and orifice restrictor.