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101.
Tarja A. Soininvaara Hannu J.A. Miettinen Jukka S. Jurvelin Esko M. Alhava Heikki P.J. Kröger 《Journal of clinical densitometry》2004,7(4):424-431
Osteoarthrosis (OA) is often associated with pain and disability, which are relieved after total knee arthroplasty (TKA), but the nature of bone changes associated with OA is controversial. We examined preoperative hip and contralateral knee bone mineral density (BMD) in patients requiring TKA and monitored the BMD changes postoperatively. Sixty-nine patients, scheduled to have TKA for osteoarthrotic knees, had both hips and contralateral knee BMD measured by dual-energy X-ray absorptiometry (DXA) at the time of operation (baseline) and at 1 yr after operation. X-rays of the knee joints were also taken to evaluate the severity of OA. Preoperatively, 27% and 38% of the patients had total hip BMD Z-score more than 1 SD in the operated side and contralateral hips, respectively. In all regions of interest (ROI), the mean baseline BMD of the affected side proximal femur was significantly lower than that of the contralateral side (p < 0.0005-0.019). The severity of OA was not associated with BMD. During 1-yr follow-up, the postoperative knee status and the physical activity of the patients (AKS score) improved. However, neither the hip nor the nonoperated knee BMDs increased. Knee OA is associated with significantly lower BMD values in the affected side compared with the contralateral hip, and these levels remained similar or decreased during a 1-yr follow-up. We conclude that improved mobility after TKA does not improve the effects of preoperative disuse-associated bone loss in the short term. 相似文献
102.
逆行交锁髓内钉治疗股骨远段骨折 总被引:11,自引:0,他引:11
目的 总结股骨逆行交锁髓内钉应用的适应证、优点及其疗效。方法 2001年6月~2003年6月,采用切开复位股骨逆行交锁髓内钉内固定,治疗股骨远段骨折21例,早期行膝关节功能锻炼。结果 18例获随访,全部骨性愈合,功能恢复良好,无膝痛、跛行、膝关节僵直等。结论 股骨逆行交锁髓内钉治疗股骨远段骨折具有明显优势,固定牢固、坚强,功能恢复快,并发症少等优点,手术不需要C臂X线机和骨科手术牵引床,适合基层医院临床应用。 相似文献
103.
大鼠骨髓间充质干细胞转染人TH基因的实验研究 总被引:1,自引:1,他引:0
目的评价酪氨酸羟化酶(tyrosine hydroxylase,TH)基因修饰骨髓间充质干细胞(mesenchymalstem cells,MSCs)后TH的表达情况及转染TH基因对MSCs的影响.方法构建含人TH基因的pCMV/hTH质粒,用脂质体转染原代培养的大鼠MSCs;Western blot及免疫细胞化学染色鉴定TH基因的表达及MSCs的分化情况;MTT比色法测定转染后的MSCs细胞活性,并与未转染的MSCs进行细胞活性比较.结果构建的pCMV/hTH质粒经ECoRI酶切后产生1.9okb和5.3kb的片段,与回收的目的基因及载体基因片段大小相符;转基因后的MSCs Western blot及免疫细胞化学染色显示TH染色阳性;转染后MSCs未见有NeuN,GFAP的表达;MTT比色法测定细胞活性,未转染与转染者差异无显著性.结论构建的TH基因能在体外培养的鼠MSCs中较好的表达,转染不会诱导MSCs向神经样细胞分化,对MSCs细胞活性无明显影响. 相似文献
104.
105.
目的目前国内对QCT骨密度测量的质量控制研究较少,本文介绍了QCT骨密度测量的准确度、精密度试验方法和意义。方法使用东芝CT机自带体模和软件为测量工具,测量四川大学华西骨质疏松研究中心等研制的QCT骨体模(称四川体模)的骨密度值。四川体模固定于15cm深的水浴中模拟人体腰椎,东芝体模置于水浴容器与扫描床面之间,按照人腰椎QCT骨密度测量相同的条件和方法进行操作,每日1次对测量体模连续测量25日,计算SD和CV,分别以25次测量125d25次测量/1d基线作3m的shewhart图。结果测量四川体模从小到大三管骨密度分别的准确度误差为-60.4%、-39.1%和-13.6%,其分别的校正系数为2.69、1.64、1.15,相关系数为0.9966,回归方程Y=35.6+0.958X(X为测量骨密度,Y为校正后骨密度)。本型QCT机骨密度测量的25次/1d及25次,25d精密度误差分别为1.25~5.54%和1.98~7.87%。25次125d的精密度误差要大于25次,d,显示机器一日内精密度误差变化小,随时间延长其变化增大。以25次125d的结果为基线绘制的shewhart图优于25次/d。结论一切QCT骨密度测量都应进行质量控制,准确度必须予以校正,精密度试验应在此基础上进行。这样结果才真实、科学、可靠并具有可比性。 相似文献
106.
Disaggregation of bone into crystals 总被引:6,自引:0,他引:6
Summary The sizes, shapes, and organizational states of the crystals in bone are studied by systematic disaggregation of the mineral
phase. This is achieved by oxidizing the organic phase with sodium hypochlorite, dispersing the resultant particles by sonication,
and separating the crystal aggregates from the crystal monomers by gravity setting in ethanol. Six different bones are compared.
Bones in which crystals are intimately associated with the collagen fibrils mostly disaggregate into crystal monomers. In
dense bones, where the crystals are mostly located between fibrils, they tend to persist as “fused” aggregates. All the crystals
are tabular or plate-shaped. In bones in which the majority of crystals are associated with the collagen fibrils, just less
than 90% of the crystals are shorter than about 450 ? in length. Their widths are on the average about 250 ?, almost an order
of magnitude larger than the diameters of individual gap regions within the collagen fibril. The notion that one crystal is
located in one gap region is therefore untenable and a reevaluation of the relations between collagen and mineral in bone
is necessary. 相似文献
107.
颈椎骨折常合并有不同程度的脊髓神经功能损伤及颈椎不稳定,对颈脊髓损伤治疗的目的是恢复颈椎的生理解剖关系,重建脊柱的稳定性,防止神经组织的继发性损伤,促进神经功能的恢复,早期无痛情况下的功能康复。2000年8月至2004年8月应用前路槽式减压自体长方体髂骨植骨钛合金钢板固定治疗下颈椎骨折46例,效果满意,总结如下。1临床资料本组46例,均为男性,年龄21~62岁,平均47·3岁。受伤原因:交通事故伤26例,坠落伤20例。骨折部位:C33例,C412例,C516例,C610例,C4、C5同时骨折5例。骨折类型:垂直压缩性骨折4例,屈曲型压缩性骨折23例,过伸型压缩… 相似文献
108.
Osteoporosis in men is recognised worldwide as an important and increasing public health problem. The causes are more heterogeneous than those in women. About 50% are diagnosed as secondary cases. In some secondary forms of osteoporosis the specific diagnosis results in additional therapeutic options (e.g. androgen therapy in proven hypogonadism). The basic therapy for osteoporosis in men is no different to that in postmenopausal women, namely recommendations for counteracting modifiable risk factors, especially with regard to diet, physical exercise, and calcium and vitamin D supplementation. Concerning specific drug medications, however, even today there is still a therapeutic dilemma in male osteoporosis. While older substances (e.g. calcitonin, fluoride, alfacalcidol) are approved for both sexes, all newer medications have primarily been approved for the treatment of postmenopausal osteoporosis. Health authorities request studies in purely male populations. For new drugs, fracture data are necessary while for new substances within a class (e.g. bisphosphonates), at the very least consistent effects on bone mineral density (BMD) and bone turnover markers are requested. Due to these regulatory rules, ibandronate, teriparatide and strontium ranelate are not approved in the European Union. Some years ago, alendronate was the first bisphosphonate that was approved for the treatment of men with osteoporosis, based on consistent results from two independent male studies using a daily 10 mg dosage. Very recently risedronate was approved by the FDA and EMEA. A randomised, placebo-controlled multicentre trial of 285 male patients showed, after 2 years, a 5.8% increase in lumbar spine BMD in the risedronate 35 mg once weekly group vs 1.2% in the placebo group. In a prospective controlled study on 316 men with primary or secondary osteoporosis we found, after 12 months, a lumbar spine BMD of +4.7% vs +1.0% in controls. The number of patients with one or more new vertebral fractures was 8 in the risedronate group and 20 in the placebo group (a fracture reduction of 60%). Furthermore, we found a significantly smaller decrease in height and a steeper decrease in back pain in the risedronate group. Risedronate is the first oral bisphosphonate available for men with the more comfortable once weekly dosage. 相似文献
109.
经皮椎体成形术中骨水泥对老年骨质疏松症患者凝血功能的影响 总被引:1,自引:0,他引:1
目的 观察经皮椎体成形术(PVP)中骨水泥对老年骨质疏松症患者凝血功能的影响.方法 于椎弓根穿刺前10 min、注入骨水泥后1、20 min、2 h分别抽血检测11例患者的凝血功能相关指标,包括血浆凝血酶原时间(PT)、活化的部分凝血酶原时间(APTT)、血浆纤维蛋白原(FIB)和鱼精蛋白副凝固实验(3P实验),并汇总数据进行统计学分析.结果 PVP中骨水泥注入后20 min,PT缩短、FIB增高、3P实验阳性率升高(P<0.05),骨水泥注入2 h后基本恢复至注入前水平.除1例患者PTA术后2 h稍高于正常值(126%),其余患者各个时间点的各项指标均在正常参考值范围内.结论 PVP术中注入骨水泥对于凝血功能正常的患者基本安全,但在注入后会产生一过性轻微的高凝倾向. 相似文献
110.
前后路联合三维矫形手术治疗青少年特发性僵硬型胸椎侧凸 总被引:1,自引:1,他引:0
目的:评价前路松解联合后路三维矫形治疗青少年特发性僵硬型胸椎侧凸的效果,探讨术中、术后并发症的预防措施。方法:青少年特发性僵硬型胸椎侧凸34例,男5例,女29例;年龄8~21岁,平均14.7岁。均为右侧凸。均采用经前路松解植骨融合联合后路三维矫形内固定治疗,其中前路经胸入路26例,胸腔镜前路松解植骨融合矫形术8例。随访时均摄全脊柱X线片。术前、术后所摄X线片进行以下各项测量指标比较:Cobb角、顶椎的旋转度、下融合椎旋转度、躯干偏移距离。随访时观察有无脊柱失平衡、假关节形成及其他并发症的发生。结果:全部病例均获随访,时间12~39个月,平均22个月。所有患者Cobb角术后平均矫正率80.62%,其中18例患者出现矫正度数丢失,丢失度数3°~10°,平均4.3°(术后平均14.2°,1年后随访平均18.5°)。所有患者术后胸椎生理性后凸得到重建。术后胸椎融合弯顶椎的旋转改善率62.91%,下融合椎旋转改善率47.60%,躯干偏移平均距离3.3mm,未见脊柱失平衡现象。围手术期并发症包括低氧血症1例,胸腔积液2例,均经保守治疗后痊愈。术后6个月肺功能检查,未见有明显下降。脊柱胸弯融合段未发现假关节形成。结论:前路松解联合后路矫形内固定植骨融合治疗青少年特发性僵硬型胸椎侧凸可明显改善顶椎的旋转度,得到满意的三维矫形效果。术前积极准备、合理手术设计,术中严格操作,术后重视预防并发症能减少手术并发症的发生。 相似文献