社区防跌倒策略在老年原发性骨质疏松症患者中的应用评价

背景　骨质疏松症（OP）患者跌倒的风险显著高于非OP者,而62%以上的低暴力骨折均由跌倒引起,因此,加强预防跌倒工作对OP患者有重要意义。但是,目前关于院内预防跌倒的研究较多,对院外预防OP患者跌倒的研究尚少。目的　评价社区防跌倒策略在老年原发性OP患者中的作用。方法　选取2016年6-12月在陆家嘴社区卫生服务中心门诊就诊的100例老年原发性OP患者,采用随机数字表法将其分为干预组和对照组,各50例。其中对照组实施常规门诊随访,干预组在对照组基础上增加社区防跌倒策略综合干预,持续干预1年。采用OP知识问卷（OKT）评估干预前后两组患者对OP知识的了解程度,采用Berg平衡量表（BBS）评估干预前后两组患者的平衡功能,采用Motricity指数（MI-L）评估干预前后两组患者的下肢肌力,统计并对比干预1年期间两组患者跌倒发生率。结果　干预后两组患者OKT评分、BBS评分、MI-L评分均较干预前升高（P<0.05）;干预前两组患者OKT评分、BBS评分、MI-L评分比较,差异无显著性（P>0.05）;干预后干预组患者OKT评分、BBS评分、MI-L评分高于对照组（P<0.05）。干预1~3个月、干预4~6个月、干预7~9个月期间,两组患者跌倒发生率比较,差异均无统计学意义（P>0.05）;干预10~12个月期间,干预组患者跌倒发生率低于对照组（P<0.05）。结论　社区防跌倒策略综合干预模式的应用可显著改善老年原发性OP患者对OP的了解程度,并且提高患者的平衡功能和下肢肌力,可有效降低患者跌倒发生率,值得推广。     

不同超声冲洗方法对根管清洗的效果观察

目的: 观察根管预备中在相同冲洗液的条件下不同超声冲洗方法对根管玷污层的清除效果。方法:
收集因正畸拔除单根管前磨牙48 颗,均采用M3 镍钛机用锉进行根管预备后随机分成4 组。A 组超声波连续冲
洗60s; B 组超声波冲洗20s,停10s 后不更换冲洗液继续冲洗( 分3 次进行) ; C 组超声冲洗20s,再用2mL 1%次
氯酸钠( NaClO) 冲洗根管( 分3 次进行) ; D 组( 对照组) 0．9%生理盐水( NaCl) 注射器冲洗60s。最后将牙体沿颊
舌向纵劈,扫描电镜观察各组样本在根颈、中、尖1 /3 玷污层的清除情况,根据评分统计分析比较各组根管清洁
效果。结果: 扫描电镜结果: C 组对玷污层的清除能力最强,且对根尖1 /3 的玷污层能起到一定的清洁作用; 统
计学结果: C 组牙本质小管开口在根尖1 /3 和根中1 /3 的数量明显多于A、B、D 组( P＜0．05) ,而A、B、C 三组根颈
处之间差异不明显( P＞0．05) 。结论: 通过扫描电镜的观察,玷污层通过超声间断冲洗伴随更换冲洗液的清洁效
果要好于超声连续冲洗后的效果。     

股骨近端防旋髓内钉手术治疗对老年股骨粗隆间骨折患者骨代谢和骨强度的影响

目的 探讨股骨近端防旋髓内钉手术(PFNA)治疗对老年股骨粗隆间骨折患者骨代谢和骨强度的影响.方法 选择2014年1月至2015年8月医院收治的老年股骨粗隆间骨折患者50例为观察组对象,另在医院健康体检处选择50例无骨折病史的正常老年人作为对照组,对观察组患者进行PFNA治疗,测定并比较手术前后观察组患者和对照组正常老年人的骨代谢和骨强度指标.结果 手术前,观察组患者骨代谢指标中前胶原氨基末端前肽Ⅰ型(PINP)、甲状旁腺激素(PTH)、Ⅰ型胶原羧基端肽(CTX)和血清骨钙素(OC)水平均明显高于对照组(均P<0.05),而25(OH)D3明显低于对照组(P<0.05);手术后,观察组患者血清PINP水平[(86.03±27.78)mg/L]较手术前[(53.97±26.13)mg/L]明显升高(P<0.05);PTH水平[(27.67±11.54)ng/L]较手术前[(51.22±17.65)ng/L]明显下降(P<0.05),略高于对照组[(36.85±12.86)ng/L](P>0.05),25(OH)D3、CTX和OC水平与手术前比较无明显变化(均P>0.05).手术前,观察组患者股骨粗隆间区以及股骨颈区骨强度指标中横截面转动贯量(CSMI)、骨密度(BMD)和截面模量z值(Z)均比对照组低(均P<0.05),屈曲比率(BR)明显高于对照组(P<0.05);手术后,观察组患者骨强度指标与手术前相比均稍有下降,但不具有统计学意义(P>0.05).结论 老年股骨粗隆间骨折患者经PFNA治疗后骨代谢增加,骨强度无明显改变,可能由于手术中应力遮挡作用而使髓内钉周围骨有少量丢失,需要加强抗骨质疏松治疗和防护措施以预防骨折.     

用骨强度概念探索骨密度测量的诊断指标

30多年来，医学上一直用骨矿密度（BMD,g/cm^2）诊断骨质疏松，骨质疏松引起骨折，骨折由骨强度减低引起，体重是骨强度的重要决定因素。 本引入体重评价BMC（g）和BMD两个指标。结果，体重与BMC的相关明显强于与BMD的相关，证明男女之间的BMC差由体重引起，男女间相同体重配对的BMC没有差异，所以在评价骨的 力学强度上体重标准化后BMC优于BMC指标。     

Improving Risk Assessment: Hip Geometry, Bone Mineral Distribution and Bone Strength in Hip Fracture Cases and Controls. The EPOS Study

Hip geometry and bone mineral density (BMD) have previously been shown to relate independently to hip fracture risk. Our objective was to determine by how much hip geometric data improved the identification of hip fracture. Lunar pencil beam scans of the proximal femur were obtained. Geometric and densitometric values from 800 female controls aged 60 years or more (from population samples which were participants in the European Prospective Osteoporosis Study, EPOS) were compared with data from 68 female hip fracture patients aged over 60 years who were scanned within 4 weeks of a contralateral hip fracture. We used Lunar DPX ‘beta’ versions of hip strength analysis (HSA) and hip axis length (HAL) applied to DPX(L) data. Compressive stress (Cstress), calculated by the HSA software to occur as a result of a typical fall on the greater trochanter, HAL, body mass index (BMI: weight/(height)²) and age were considered alongside femoral neck BMD (FN-BMD, g/cm²) as potential predictors of fracture. Logistic regression was used to generate predictors of fracture initially from FN-BMD. Next age, Cstress (as the most discriminating HSA-derived parameter), HAL and BMI were added to the model as potentially independent predictors. It was not necessary to include both HAL and Cstress in the logistic models, so the entire data set was examined without excluding the subjects missing HAL measurements. Cstress combined with age and BMI provided significantly better prediction of fracture than FN-BMD used alone as is current practice, judged by comparing areas under receiver operating characteristic (ROC) curves (p<0.001, deLong’s test). At a specificity of 80%, sensitivity in identification was improved from 66% to 81%. Identifying women at high risk of hip fracture is thus likely to be substantially enhanced by combining bone density with age, simple anthropometry and data on the structural geometry of the hip. HSA might prove to be a valuable enhancement of DXA densitometry in clinical practice and its use could justify a more pro-active approach to identifying women at high risk of hip fracture in the community. Received: 16 March 2001 / Accepted: 3 August 2001     

The association between isoinertial trunk muscle performance and low back pain in male adolescents

The literature reports inconsistent findings regarding the association between low back pain (LBP) and trunk muscle function, in both adults and children. The strength of the relationship appears to be influenced by how LBP is qualified and the means by which muscle function is measured. The aim of this study was to examine the association between isoinertial trunk muscle performance and consequential (non-trivial) low back pain (LBP) in male adolescents. Healthy male adolescents underwent anthropometric measurements, clinical evaluation, and tests of trunk range of motion (ROM), maximum isometric strength (STRENGTH) and peak movement velocity (VEL), using an isoinertial device. They provided information about their regular sporting activities, history and family history of LBP. Predictors of “relevant/consequential LBP” were examined using multivariable logistic regression. LBP status was reassessed after 2 years and the change from baseline was categorised. At baseline, 33/95 (35%) subjects reported having experienced consequential LBP. BMI, a family history of LBP, and regularly playing sport were each significantly associated with a history of consequential LBP (p < 0.05). 85/95 (89%) boys participated in the follow-up: 51 (60%) reported no LBP at either baseline or follow-up (never LBP); 5 (6%) no LBP at baseline, but LBP at follow-up (new LBP); 19 (22%) LBP at baseline, but none at follow-up; and 10 (12%) LBP at both time-points (recurrent/persistent LBP). The only distinguishing features of group membership in these small groups were: fewer sport-active in the “never LBP” group); worse trunk mobility, in the “persistent LBP” group, lower baseline sagittal ROM in the “never LBP” and “new LBP” (p < 0.05). Regular involvement in sport was a consistent predictor of LBP. Isoinertial trunk performance was not associated with LBP in adolescents.     

胸主动脉夹层动脉瘤假腔壁力学分析的动物实验

目的从力学的角度分析腹主动脉瘤破裂和胸主动脉夹层动脉瘤破裂的原因。方法通过胸主动脉夹层假腔内外层的屈服形状改变比能,发现两者间的关系。结果60%的实验犬形成夹层模型。假腔内层的形状改变比能测试结果差异有统计学意义。结论当胸主动脉管壁遭遇大于内层屈服形状改变比能而又小于外层屈服形状改变比能的血流冲击时,就会导致中膜分离形成夹层。     

Pullout strength of anterior spinal instrumentation: a product comparison of seven screws in calf vertebral bodies

A lot of new implant devices for spine surgery are coming onto the market, in which vertebral screws play a fundamental role. The new screws developed for surgery of spine deformities have to be compared to established systems. A biomechanical in vitro study was designed to assess the bone–screw interface fixation strength of seven different screws used for correction of scoliosis in spine surgery. The objectives of the current study were twofold: (1) to evaluate the initial strength at the bone–screw interface of newly developed vertebral screws (Universal Spine System II) compared to established systems (product comparison) and (2) to evaluate the influence of screw design, screw diameter, screw length and bone mineral density on pullout strength. Fifty-six calf vertebral bodies were instrumented with seven different screws (USS II anterior 8.0 mm, USS II posterior 6.2 mm, KASS 6.25 mm, USS II anterior 6.2 mm, USS II posterior 5.2 mm, USS 6.0 mm, USS 5.0 mm). Bone mineral density (BMD) was determined by quantitative computed tomography (QCT). Failure in axial pullout was tested using a displacement-controlled universal test machine. USS II anterior 8.0 mm showed higher pullout strength than all other screws. The difference constituted a tendency (P = 0.108) when compared to USS II posterior 6.2 mm (+19%) and was significant in comparison to the other screws (+30 to +55%, P < 0.002). USS II posterior 6.2 mm showed significantly higher pullout strength than USS 5.0 mm (+30%, P = 0.014). The other screws did not differ significantly in pullout strength. Pullout strength correlated significantly with BMD (P = 0.0015) and vertebral body width/screw length (P < 0.001). The newly developed screws for spine surgery (USS II) show higher pullout strength when compared to established systems. Screw design had no significant influence on pullout force in vertebral body screws, but outer diameter of the screw, screw length and BMD are good predictors of pullout resistance.     

Depression of NMDA-receptor-mediated segmental transmission by ketamine and ketoprofen, but not L-NAME, on the in vitro neonatal rat spinal cord preparation

Activation of spinal N-methyl-D-aspartate (NMDA) receptors and then the nitric oxide and the arachidonic acid pathways is important in pain transmission. This study assessed the effects of the NMDA receptor channel blocker ketamine, the nitric oxide synthase inhibitor L-NAME, and the cyclooxygenase inhibitor ketoprofen in nociceptive transmission using an in vitro neonatal rat spinal cord preparation. Supramaximal electrical stimulation of the dorsal root evoked the A-fibre- and C-fibre-mediated high intensity excitatory postsynaptic potential (EPSP) in the ipsilateral ventral root. Low intensity stimulation evoked the A-fibre-mediated monosynaptic compound action potential (MSR) superimposed on the low intensity EPSP. Both the low intensity EPSP and the high intensity EPSP contain NMDA-receptor-mediated components. Only ketamine and ketoprofen depressed the synaptic responses. Ketamine depressed all three spinal reflexes with IC(50) values (with 95% CI) of 10.80 microM (5.97 to 19.54 microM) for the MSR, 8.29 microM (4.53 to 14.17 microM) for the low intensity EPSP, and 5.35 microM (3.05 to 9.40 microM) for the high intensity EPSP. Ketoprofen depressed the low intensity EPSP and the high intensity EPSP only; IC(50) values (with 95% CI) were 354.5 microM (217.5 to 576.8 microM) and 302.7 microM (174.0 to 526.7 microM), respectively. Reflexes recovered after drug washout. These data demonstrated that ketamine and ketoprofen, but not L-NAME, depressed NMDA-mediated nociceptive transmission in spinal cord preparations from neonatal rats.     

Influence of internal fixator flexibility on murine fracture healing as characterized by mechanical testing and microCT imaging

Mechanically well‐defined stabilization systems have only recently become available, providing standardized conditions for studying the role of the mechanical environment on mouse bone fracture healing. The aim of this study was to characterize the time course of strength recovery and callus development of mouse femoral osteotomies stabilized with either low or high flexibility (in bending and torsion) internal fixation plates. Animals were euthanized and femora excised at 14, 21, and 28 days post‐osteotomy for microCT analysis and torsional strength testing. While a larger mineralized callus was observed in osteotomies under more flexible conditions at all time points, the earlier bridging of the mineralized callus under less flexible conditions by 1 week resulted in an earlier recovery of torsional strength in mice stabilized with low flexibility fixation. Ultimate torque values for these bones were significantly higher at 14 and 21 days post‐osteotomy compared to bones with the more flexible stabilization. Our study confirms the high reproducibility of the results that are achieved with this new implant system, therefore making it ideal for studying the influence of the mechanical environment on murine fracture healing under highly standardized conditions. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1245–1250, 2011