环磷酰胺对大鼠骨密度和骨微结构的影响

目的：研究不同剂量环磷酰胺对雌性SD大鼠骨密度和骨微结构的影响。方法40只3月龄SD雌性大鼠随机数字表法分为环磷酰胺低剂量组、中剂量组、高剂量组和对照组,每组各10只,环磷酰胺各组分别腹腔注射不同剂量（5 mg／kg、8 mg／kg、10 mg／kg）的环磷酰胺,对照组腹腔注射等量生理盐水,每天一次,连续15天,观察大鼠骨密度及骨微结构等指标。结果不同剂量的环磷酰胺组与对照组比较,全身骨密度分别下降了9．8％、13．3％和15．6％;股骨骨小梁数目分别下降了49．8％、65．5％和72．8％;股骨骨小梁分离度则分别上升了225．2％、416．9％和577．4％。结论环磷酰胺可使大鼠骨密度降低,骨小梁数量减少,骨微结构受损,且环磷酰胺剂量越大,骨微结构受损越严重。     

高原汉族农民跟骨定量超声测定结果的分析研究

目的：探讨高原环境对体力劳动者骨量变化的影响。方法：采用UBIS3000型定量超声仪，对生活在海拔3000m高原的567名汉族农民跟骨定量超声参数进行测定。结果：超声振幅衰减(BUA)、刚度(STI)的峰值男性为40～49岁，女性为30～39岁，超声声速(SOS)峰值男女性均为40～49岁，50岁以后各项指标均明显下降。结论：体力劳动和高原环境因素都对骨量变化产生重要影响，高原农民年轻时高强度的体力劳动对骨量的影响大于高原环境因素的影响，老年后随劳动量减少骨量迅速丢失。     

跟骨定量超声法评价正常女性骨丢失和骨质疏松患病率

目的　评价正常女性跟骨超声随增龄骨量丢失及骨质疏松患病率。方法　用定量超声法测定了 2 72例正常女性右跟骨宽带超声衰减 (BUA) ,超声声速 (SOS)及骨硬度指数 (STI)。结果女性跟骨峰值骨量出现在 30～ 39岁。 5 0～ 84岁 3组与峰值组以及两两之间比较 ,差异均有显著性(P <0 0 1)。老年组骨质丢失率和骨质疏松患病率分别为 2 6 %～ 37%和 4 2 %～ 6 9%。在各个年龄组中 ,STI丢失率最高 ;STI和BUA骨质疏松检出率相近 ,均大于SOS。结论　跟骨超声的 3项指标均可用于区分绝经前、后的妇女 ;STI检测骨量丢失和OP患病率最敏感     

骨质疏松髋部骨折区骨微结构变化研究

目的 分析骨质疏松髋部骨折区张力侧骨小梁微结构的变化。方法 实验组选择16例低能量创伤致股骨颈骨折需要行髋关节置换的老年患者,术前行健侧髋部骨密度检测。因活体取材困难,故选取5根青年同种异体股骨为对照组。在实验组与对照组股骨颈张力侧骨小梁中,切取5mm×5mm×10mm的松质骨,行Micro-CT扫描分析微结构参数。分析两组之间微结构参数的差异及实验组患者微结构参数与骨密度之间关系。结果 实验组微结构：骨体积分数(BV/TV) 0.0645±0.0259,骨小梁数量(Tb.N) (0.8078±0.2212) mm-1,骨小梁厚度(Tb.Th ) (0.0836±0.0212) mm, 骨小梁距离(Tb.Sp) (1.2197±0.4492) mm,连接密度(Conn.D) 1.8577±1.0217, 结构模型指数(SMI) 1.7780±0.5168。对照组微结构：BV/TV 0.1470±0.0633,Tb.N (1.2692±0.1376)mm－1,Tb.Th (0.1201±0.0414) mm,Tb.Sp (0.6810±0.1129) mm,Conn.D 3.3585±1.7851,SMI 0.8781±0.6665。与对照组相比,实验组髋部张力侧松质骨小梁显著破坏,各微结构指标均有明显的改变,差异有统计学意义（P＜0.05）。实验组微结构参数与骨密度之间无相关性（P＞0.05）。结论 骨质疏松髋部骨折区张力侧骨小梁明显破坏,这可能是髋部骨折发生的重要原因之一。     

ω-3多不饱和脂肪酸对去势大鼠骨微结构的改善

目的观察ω-3多不饱和脂肪酸(PUFA)对去势大鼠骨微结构的影响。方法将30只雌性大鼠随机分为假手术组、模型组和实验组。假手术组仅切除卵巢周围脂肪组织,其余两组切除双侧卵巢。模型组和假手术组给予1 m L/(100 g·d)的生理盐水灌胃,实验组给予ω-3 PUFA 150 mg/(kg·d)。干预12 w后,处死所有大鼠,检测血钙、磷、碱性磷酸酶(ALP)和雌激素水平。分离右侧整段股骨应用micro-CT检测骨密度和骨微结构。结果雌二醇在3组之间存在显著差异,表现为模型组水平最低(8.1±2.8)mmol/L,而假手术组水平最高(25.0±8.9)mmol/L(P0.05)。实验组松质骨骨密度[(0.180±0.022)g/cm3vs(0.135±0.017)g/cm3]、BV/TV[(36.422±10.893)%vs(29.631±9.705)%]、Tb.Th[(0.138±0.044)mm vs(0.117±0.039)mm]和Tb.N[(2.252±0.078)/mm vs(1.589±0.083)/mm]均显著高于模型组,而Tb.Sp[(0.404±0.020)mm vs(0.599±0.032)mm]显著低于模型组(P0.05);实验组皮质骨骨密度[(0.718±0.015)g/cm3vs(0.633±0.025)g/cm3]、BV/TV[(48.559±7.152)%vs(33.878±8.764)%]和Cr.Th[(0.483±0.037)mm vs(0.428±0.034)mm]均显著高于模型组,而孔隙率[(32.162±7.891)%vs(38.859±9.847)%]显著低于模型组(P0.05)。结论ω-3PUFA对去卵巢大鼠的骨微结构有一定的改善作用,这对于防治骨质疏松具有一定的意义。     

井上、井下矿工跟骨定量超声测定分析

目的 通过对井下、井上煤矿工人跟骨定量超声测定进行对比观察，探讨井下工作因缺氧、有机气体、煤尘、潮湿、阳光照射不足等因素对骨代谢的影响。方法 采用UBIS3000型定量超声仪，对200名工人跟骨进行定量超声测定，并将井下、井上测定结果分别进行对比分析，年龄为井下20～48岁。井上为20～54岁。均为男性。结果 井下工作跟骨超声振幅衰减(BUA)，骨刚度(STI)和超声声速(SOS)明显低于井上。结论 井下工作因受环境因素的影响。导致骨代谢的异常，骨吸收增加，提示井下工人及时进行预防治疗，避免骨质疏松的发生，减少骨折发生的因素。     

跟骨钢板治疗跟骨粉碎性骨折

跟骨骨折波及跟距关节面,治疗不当会遗留跟痛、创伤性关节炎、扁平足等,严重影响患肢功能,病废率高。2005年3月～2007年5月,我院采用跟骨钢板治疗跟骨骨折23例,取得满意疗效。     

跟骨钢板治疗跟骨骨折

2001年1月～2005年3月,我科采用跟骨钢板治疗跟骨骨折20例,疗效满意。     

跟骨钢板治疗跟骨粉碎性骨折的疗效分析

目的 探讨跟骨钢板治疗跟骨粉碎性骨折的效果.方法 对57例跟骨粉碎性骨折采用跟骨钢板内固定.术后进行疗效评定,并对治疗前后的B6hler角和Gissane角变化和并发症进行观察.结果 Sanders Ⅱ型、Ⅲ型、Ⅳ型骨折优良率分别为92.00%;77.78%,63.64%.治疗后,B6hler角和Gissane角得到恢复,与治疗前比较统计有意义(P<0.05).结论 采用跟骨钢板治疗跟骨粉碎性骨折,对Sanders Ⅱ型骨折的效果最佳,并能恢复B6hler角和Gissane角,是值得推荐的一种治疗方法.     

骨量、微结构及受力方向对去卵巢大鼠骨生物力学的影响

目的观察骨质疏松模型大鼠骨量、骨微结构和骨的受力方向与生物力学变化的关系。方法6～7月龄Wistar大鼠50只,随机分为正常对照组25只,去势模型组25只,12周后处死全部大鼠,测定大鼠全身、股骨和腰椎(L4～L6)骨密度,对左侧股骨进行三点弯曲试验,右侧股骨沿载荷倾斜20°角进行压力试验,对椎体(L4)进行压缩试验,把部分股骨和腰椎(L5)制成切片进行免疫组化染色,观察它们的形态计量学变化。结果去势组大鼠的全身、股骨和腰椎(L4～L6)骨密度比对照组明显减少(P<0.05),去势组大鼠右侧股骨沿载荷倾斜20°角后的结构力学性能和椎体的最大压缩力较正常对照组明显降低(P<0.05),但两者左侧股骨的结构力学性能差异无显著性(P>0.05),去势后大鼠股骨的材料力学性能较对照组明显下降(P<0.05),组化染色显示去势组大鼠的骨小梁较正常组稀疏减少,尤以松质骨明显。结论大鼠去势后松质骨的骨量、骨微结构较皮质骨变化明显,且骨量、骨微结构和骨的受力方向对骨的生物力学都有着重要影响。     

MRI对于骨质疏松性椎体压缩性骨折的诊断价值(新鲜骨折与陈旧性骨折的鉴别)

为探讨MRI对骨质疏松性新鲜与陈旧椎体骨折的鉴别诊断意义,对17例老年人骨质疏松性椎体压缩性骨折于初诊及伤后3、6、12个月行胸腰椎MRI检查,记录其信号改变。并对其腰背痛程度进行评价。结果显示17例骨折椎体急性期均表现为T_1加权像低信号、T_2加权像高信号,伤后逐渐恢复正常。伤后不同时间MRI检查结果相差十分显著(P<0.01)。其腰背痛症状也逐渐减轻,伤后不同时间相差十分显著(P<0.01)。认为MRI可鉴别骨质疏松性新鲜与陈旧骨折,当骨质疏松患者同时存在多个椎体变形时则更具诊断价值。     

Feasibility of in vivo structural analysis of high-resolution magnetic resonance images of the proximal femur

Previously, high resolution MRI to assess bone structure of deep-seated regions of the skeleton such as the proximal femur was substantially limited by signal-to-noise ratio (SNR). With the advent of new optimized pulse sequences in MRI at 1.5 T and 3 T, it may now be possible to depict and quantify the trabecular microarchitecture in the proximal femur. The purpose of this study was to investigate the feasibility of assessing trabecular microstructure of the human proximal femur in vivo with MR imaging at 1.5 T and 3 T. MR images of six young, healthy male and female subjects were acquired using standard clinical 1.5-T and high-field 3-T whole-body MR scanners. Using a T2/T1-weighted 3D FIESTA sequence (and a 3D FIESTA-C sequence at 3 T to avoid susceptibility artifacts) a resolution of 0.234 × 0.234 × 1.5 mm³ was achieved in vivo. Structural parameters analogous to standard bone histomorphometry were determined in femoral head and trochanter regions of interest. Bone mineral density (BMD) measurements were also obtained using dual-energy X-ray absorptiometry (DXA) for the femoral trochanter in the same subjects. The bone structure of the proximal femur is substantially better depicted at 3 T than at 1.5 T. Correlation between the structural parameters obtained at both field strengths was up to R =0.86 for both the femoral head and the trochanteric region. However, the resolution of the images limits the application of 3D structural analysis, making the assessment more akin to 2D textural measures, which may be correlated to histomorphometric but are not identical measures. This feasibility study establishes the potential of MRI as a means of imaging proximal femur structure, and improvements in technique and resolution enhancements are warranted.     

Ultrasound parametric imaging of the calcaneus:In vivo results with a new device

An ultrasound transmission scanning system was constructed to makein vivo parametric images of the acoustic properties of the heel. Broadband ultrasonic attenuation (BUA) images were obtained in transmit mode by using a pair of broadband focused transducers (center frequency 0.5 MHz, diameter 29 mm, focus 50 mm) immersed in a water bath at room temperature. With these characteristics, the theoretical beam width at the focus was approximately 5 mm. The total duration of the acquisition period was 3 minutes. Comparison of the BUA image and the radiograph of the calcaneus was possible in one case and showed that all the anatomical details could be identified. The images reported here demonstrate the wide range of BUA found in both the whole bone and within a ROI centered in the posterior part of the bone thus reinforcing the idea of tremendous heterogeneity of the acoustic properties of bone. This suggests that the accurate control of the position of the measurement site is of the utmost importance for between-subject comparison and for repetitive measurements. We proposed a new method, the likelihood image, as an efficient way of highlighting the regions of the image suspected to be subject to waveform distortion. It could be used to guide the selection of the optimal measurement site. Our results suggest that ultrasound parametric imaging has the potential for enhancing the current ultrasound technique by (1) allowing reproducible, repetitive measurements, (2) permitting the selection of similar optimal measurement sites in all subjects, and (3) avoiding accuracy erros due to wave-form distortion.     

Assessment of trabecular bone structure comparing magnetic resonance imaging at 3 Tesla with high-resolution peripheral quantitative computed tomography ex vivo and in vivo

Summary In vivo high-resolution peripheral quantitative micro-CT (HR-pQCT) is a new modality for imaging peripheral sites like the distal tibia and the distal radius, providing structural bone parameters. Comparing HR-pQCT with MRI, we found that both modalities are capable of offering meaningful information on trabecular structure. Background Magnetic resonance imaging (MRI) has emerged as the leading in vivo method for measuring trabecular bone micro-architecture and providing structural information. Recently, an in vivo HR-pQCT modality was introduced for imaging peripheral sites like the distal tibia and the distal radius, providing structural bone parameters. The goal of this work was to compare and evaluate the performances and in vivo capabilities of HR-pQCT in comparison with MRI at 3 Tesla. Methods To this end images of 8 human specimens (5 tibiae and 3 radii) and 11 participants (6 tibia and 5 radii) were acquired with both modalities. Additionally, the radius specimens were scanned with micro-CT (μCT), which was used as a standard of reference. Structural parameters calculated from MRI were compared with results from HR-pQCT images and additionally μCT for the radii specimens. Results High correlations (r > 0.7) were found for trabecular number and trabecular spacing between the two modalities in vivo and ex vivo. 2D and 3D analysis revealed high correlations (r > 0.8) in structural bone parameters for all measurements. Using micro-CT as standard of reference both results from QCT and MRI correlated well. Conclusion Both imaging modalities were found to perform equally well regarding trabecular bone measurements.     

The relationship between ultrasound and densitometric measurements of bone mass at the calcaneus in women

Summary Broadband ultrasound attenuation (BUA) of the calcaneus predicts axial density in women and is decreased in women who sustain hip fractures. To determine the relationship between ultrasonic and densitometric assessments of bone mass at the same site, BUA and velocity of sound (VOS) were correlated with bone density as measured by dual energy x-ray absorptiometry (DXA) at the calcaneus in 64 Caucasian women aged 35–83 years. BUA, VOS, and bone density in these women decreased annually as a function of age by 1.0%, 0.3%, and 0.9%, respectively. Holding age, years since menopause, height and weight constant, BUA correlated with VOS (r=0.74, P<0.001), and calcaneal density correlated with BUA (r=0.73, P<0.001) and with VOS (r=0.66, P<0.01). The results indicate that both BUA and VOS measurements reflect density at the calcaneus, but suggest that they measure properties of bone other than density and different from each other. The assessment of these additional properties may be useful in the prediction of fracture risk.     

贵阳地区709例男性超声跟骨强度及影响因素调查

目的 了解贵阳地区男性人群的骨强度情况及影响因素,为骨质疏松的防治提供参考依据.方法 采用定量超声的方法对贵阳地区709例20～65岁男性人群进行右侧跟骨强度测量,并进行问卷调查;指标有骨强度指数、T值和Z值.结果 跟骨强度指数有随年龄增加逐渐下降的趋势;运动组的强度指数有高于非运动组的趋势;单纯饮用牛奶对增强骨强度效果不明显;跟骨强度指数基本上呈现既运动又饮奶组>只运动组>只饮奶组>不运动不饮奶组的趋势;本人群的运动和饮奶状况均不理想.结论 在饮用牛奶的同时坚持体育锻炼会对骨强度起到明显的增强作用.     

Ultrasound attenuation of the calcaneus in the female population: Normative data

Summary Broadband ultrasound attenuation (BUA) on the os calcis has been proposed as a safe and reliable technique for evaluating skeleted status. The present study provides preliminary normative BUA results on 93 female subjects divided into five age groups. These data can be used as a guide for comparing the results of individual studies. The diagnosis of osteoporosis was determined from lateral calcaneus and spine radiographs. Postmenopausal osteoporotic female subjects had significantly lower BUA values than normal women (P <0.001). There was a significant negative linear relationship between BUA and age in the postmenopausal subjects. No correlation was found between body size pararneters (weight, height, and body mass index) and ultrasound attenuation. These results indicate that BUA may be a useful technique for detection of persons at risk.     

Bone structure of the calcaneus: analysis with magnetic resonance imaging and correlation with histomorphometric study

The purpose of this study was to compare structural measurements obtained from MR images of the calcaneus with those obtained from conventional histomorphometry. Sagittal magnetic resonance (MR) images of the calcaneus of 24 fresh human cadaveric feet were obtained at a spatial resolution achievable in vivo. A three-dimensional gradient echo-sequence was used with a slice thickness of 700 m and in plane resolution of 172×172 m. Structural analysis (four histomorphometric parameters; seven connectivity parameters) was performed in the superior region of the calcaneus. Bone biopsy specimens were obtained in the same area and were sectioned for histomorphometric study. Most of the MR histomorphometric parameters were overestimated (by a factor ranging from 0.8 to 3), as compared with histomorphometry. However, significant (P<0.05) correlations were found between MR imaging and histomorphometric measurements for bone volume/tissue volume, trabecular separation, trabecular number, star volume of the marrow space, node count and terminus count. MR histomorphometric parameters correlated much better with histomorphometry than connectivity parameters. This study suggests that structural parameters characterizing cancellous bone in the calcaneus can be derived from MR images in the limited spatial resolution regime applicable in vivo.     

MRI quantification of fatty infiltration and muscle atrophy in a mouse model of rotator cuff tears

Rotator cuff pathology is the most common shoulder problem seen by orthopedic surgeons. Rotator cuff muscle fatty infiltration and muscle atrophy are common in larger tears and are considered predicting factors for the prognosis of cuff repair. Clinically, MRI is the gold standard in determining fatty infiltration and muscle atrophy; however, analysis for MRI imaging is primarily qualitative in nature with the results lacking further validation. We have recently developed a mouse model of rotator cuff tears. The goal of this study is to quantify and verify rotator cuff muscle atrophy and fatty infiltration using high‐resolution MRI in our mouse model. The rotator cuff muscles were analyzed for fat using a triglyceride quantification assay (TQA), muscle volume was measured through water displacement (WD), and histology. The study revealed that MRI had a high correlation with fat as measured with histology and TQA (R² = 098). MRI also correlated well with atrophy measured with WD and wet weight. This suggests that MRI is a reliable modality in evaluating the progression of fatty infiltration and muscle atrophy following rotator cuff tears in a small animal model. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 421–426, 2013