A Comparison of Bone Mineral Density and Its Predictors in HIV-Infected and HIV-Uninfected Older Men

ObjectiveBone health in older individuals with HIV infection has not been well studied. This study aimed to compare bone mineral density (BMD), trabecular bone score (TBS), and bone markers between HIV-infected men and age- and body mass index (BMI)-matched HIV-uninfected men aged ≥60 years. We investigated the associations of risk factors related to fracture with BMD, TBS, and bone markers in HIV-infected men.MethodsThis cross-sectional study included 45 HIV-infected men receiving antiretroviral therapy and 42 HIV-uninfected men. Medical history, BMD and TBS measurements, and laboratory tests related to bone health were assessed in all the participants. HIV-related factors known to be associated with bone loss were assessed in the HIV-infected men.ResultsThe mean BMD, TBS, and osteopenia or osteoporosis prevalence were similar among the cases and controls. The HIV-infected men had significantly higher mean N-terminal propeptide of type 1 procollagen and C-terminal cross-linking telopeptide of type I collagen levels. Stepwise multiple linear regression analysis demonstrated that low BMI (lumbar spine, P = .015; femoral neck, P = .018; and total hip, P = .005), high C-terminal cross-linking telopeptide of type I collagen concentration (total hip, P = .042; and TBS, P = .010), and low vitamin D supplementation (TBS, P = .035) were independently associated with low BMD and TBS.ConclusionIn older HIV-infected men with a low fracture risk, the mean BMD and TBS were similar to those of the age- and BMI-matched controls. The mean bone marker levels were higher in the HIV group. Traditional risk factors for fracture, including low BMI, high C-terminal cross-linking telopeptide of type I collagen level, and low vitamin D supplementation, were significant predictors of low BMD and TBS.     

Influence of muscle activity on the forces in the femur: An in vivo study

Experiments were performed on two patients with custom-made instrumented massive proximal femoral prostheses implanted after tumour resection. In vivo axial forces transmitted along the prostheses were telemetered during level walking, single- and double-leg stance, and isometric exercises of the hip muscles. These activities varied the lever arms available to the external loads: minimum for double-leg stance and maximum for hip isometric exercises. Kinematic, force plate, EMG and telemetered force data were recorded simultaneously. The force magnification ration (FMR; the ratio of the telemetered axial force to the external force) was calculated. The FMRs ranged from 1.3 (during double-leg stance) to 29.8 (during abductors test), indicating that a major part of the axial force in the long bones is a response to muscle activity, the strength of which depends on the lever arms available to the external loads. From these results, it was shown that the bulk of the bending moment along limbs is transmitted by a combination of tensile forces in muscles and compressive forces in bones, so moments transmitted by the bones are smaller than the limb moments. It was concluded that appropriate simulation of muscle forces is important in experimental or theoretical studies of load transmission along bones.     

Protective effect of Agrimonia pilosa polysaccharides on dexamethasone‐treated MC3T3‐E1 cells via Wnt/β‐Catenin pathway

A water‐soluble polysaccharide (APP‐AW) was isolated from Agrimonia pilosa and prepared to three sulphated derivatives (S1, S2 and S3). The results showed that pre‐treatment with APP‐AW, S1, S2 and S3 each at the concentration of 50 μg/mL for 48 hours was able to prevent cytotoxicity induced by 1 μmol/L dexamethasone (Dex) in MC3T3‐E1 cells via inhibition of apoptosis, which is in line with the findings in flow cytometry analysis. Meanwhile, the decreased ALP activity, collagen content, mineralization, BMP2, Runx2, OSX and OCN protein expression in DEX‐treated MC3T3‐E1 cells were reversed by the addition of APP‐AW, S1, S2 and S3. Moreover, APP‐AW, S1, S2 and S3 rescued DEX‐induced increase of Bax, cytochrome c and caspase‐3 and decrease of Bcl‐2, Wnt3, β‐catenin and c‐Myc protein expression in MC3T3‐E1 cells. Our findings suggest that pre‐treatment with APP‐AW, S1, S2 and S3 could significantly protect MC3T3‐E1 cells against Dex‐induced cell injury via inhibiting apoptosis and activating Wnt/β‐Catenin signalling pathway, thus application of these polysaccharides may be a promising alternative strategy for steroid‐induced avascular necrosis of the femoral head (SANFH) therapy.     

Osthole stimulates bone formation,drives vascularization and retards adipogenesis to alleviate alcohol‐induced osteonecrosis of the femoral head

Characteristic pathological changes in osteonecrosis of the femoral head (ONFH) include reduced osteogenic differentiation of bone mesenchymal stem cells (BMSCs), impaired osseous circulation and increased intramedullary adipocytes deposition. Osthole is a bioactive derivative from coumarin with a wide range of pharmacotherapeutic effects. The aim of this study was to unveil the potential protective role of osthole in alcohol‐induced ONFH. In vitro, ethanol (50 mmol/L) remarkably decreased the proliferation and osteogenic differentiation of BMSCs and impaired the proliferation and tube formation capacity of human umbilical vein endothelial cell (HUVECs), whereas it substantially promoted the adipogenic differentiation of BMSCs. However, osthole could reverse the effects of ethanol on osteogenesis via modulating Wnt/β‐catenin pathway, stimulate vasculogenesis and counteract adipogenesis. In vivo, the protective role of osthole was confirmed in the well‐constructed rat model of ethanol‐induced ONFH, demonstrated by a cascade of radiographical and pathological investigations including micro‐CT scanning, haematoxylin‐eosin staining, TdT‐mediated dUTP nick end labelling, immunohistochemical staining and fluorochrome labelling. Taken together, for the first time, osthole was demonstrated to rescue the ethanol‐induced ONFH via promoting bone formation, driving vascularization and retarding adipogenesis.     

髓内固定对老年股骨转子间骨折患者关节功能的影响

摘要 目的：研究髓内固定对老年股骨转子间骨折患者关节功能的影响。方法：选取2016年9月~2019年9月我院收治的股骨转子间骨折的老年患者80例为研究对象,采用随机数字表法将其分为两组,每组各40例。对照组患者采用Gamma钉进行治疗,观察组患者采用股骨近端防旋髓内钉固定治疗。比较两组患者的围术期相关指标、骨折愈合时间、Harris评分、临床治疗效果及并发症的发生情况。结果：观察组患者的手术时间、切口长度、术中出血量、术后引流量、住院时间及骨折愈合时间均显著少于或短于对照组(P＜0.05)。术前,两组患者的Harris评分比较无统计学差异(P＞0.05);术后6个月及术后12个月,两组患者的Harris评分均较术前显著升高,且观察组显著高于对照组(P＜0.05)。观察组患者的治疗优良率为92.50 %,显著高于对照组(75.00 %,P＜0.05)。两组患者深静脉血栓、感染、褥疮、固定松动、股骨头坏死及严重疼痛的发生率比较无统计学差异(P＞0.05)。结论：股骨近端防旋髓内钉固定治疗老年股骨转子间骨折效果明显优于Gamma钉治疗,可有效缩短骨折愈合时间,提高髋关节功能。     

切开与闭合复位空心钉内固定对移位股骨颈骨折患者骨折复位质量和髋关节功能的影响

摘要 目的：探讨切开与闭合复位空心钉内固定对移位股骨颈骨折患者骨折复位质量和髋关节功能的影响。方法：本研究为回顾性研究,选取98例移位股骨颈骨折患者的临床资料,根据手术方式的不同将患者分为A组（n=50,切开复位）和B组（n=48,闭合复位）,比较两组患者优良率、骨折复位质量、髋关节功能、围术期指标、术后并发症发生率和二次手术发生率。结果：A组患者术后6个月的优良率为78.00%（39/50）,高于B组的58.33%（28/48）（P<0.05）。两组术后负重下地时间、术中透视时间比较无差异（P>0.05）;B组手术时间、住院时间短于A组,术中出血量少于A组（P<0.05）。两组患者术后1个月、术后3个月、术后6个月髋关节功能Harris评分均较术前升高,且A组高于B组（P<0.05）。两组二次手术及并发症发生率比较无差异（P>0.05）。A组Ⅰ型、Ⅱ型的例数均多于B组,Ⅲ型例数少于B组（P<0.05）。结论：与闭合复位空心钉内固定相比,切开复位空心钉内固定虽损伤较大,但其术后骨折复位质量和髋关节功能改善效果更佳,且不增加并发症发生率和二次手术发生率。     

隐匿性胫骨平台骨折MRI、CT检查的影像学表现及其诊断价值对比的回顾性研究

目的:研究对比隐匿性胫骨平台骨折(TPOF)磁共振成像(MRI)、电子计算机断层扫描(CT)检查的影像学表现及其诊断价值。方法:回顾性分析我院自2016年1月至2019年12月拟诊断为TPOF且X线检查表现为阴性的89例患者的临床资料,分别对所有受试者进行MRI、CT检查,且以手术检查为金标准,比较上述两种影像学检查手段诊断TPOF的效能。此外,比较MRI、CT检查诊断TPOF的表观扩散系数以及节段各向异性值以及对TPOF类型的检出率。结果:MRI检查诊断TPOF的灵敏度、特异度及准确度分别为98.61%、94.12%、97.75%,均高于CT检查的79.17%、64.71%、76.40%(均P<0.05)。MRI检查诊断TPOF的表观扩散系数高于CT检查,而节段各向异性值低于CT检查(均P<0.05)。MRI检查对骨皮质骨折的检出率低于CT检查,而对骨小梁骨折的检出率高于CT检查(均P<0.05)。结论:MRI检查诊断TPOF的价值高于CT检查,且在骨小梁骨折的检出率方面优于CT检查,但CT检查应用于骨皮质骨折的诊断价值更高。临床工作中可能通过联合MRI以及CT检查,继而达到提高TPOF检出率的目的。     

A Comparative Analysis of Different Treatments for Distal Femur Fractures using the Finite Element Method

The main objective of this work is the evaluation, by means of the finite element method (FEM) of the mechanical stability and long-term microstructural modifications in bone induced to three different kinds of fractures of the distal femur by three types of implants: the Condyle Plate, the less invasive stabilization system plate (LISS) and the distal femur nail (DFN). The displacement and the stress distributions both in bone and implants and the internal bone remodelling process after fracture and fixation are obtained and analysed by computational simulation. The main conclusions of this work are that distal femoral fractures can be treated correctly with the Condyle Plate, the LISS plate and the DFN. The stresses both in LISS and DFN implant are high especially around the screws. When respect to remodelling, the LISS produces an important resorption in the fractured region, while the other two implants do not strongly modify bone tissue microstructure.     

Automated localisation and boundary identification of superficial femoral artery on MRI sequences

In this paper, an automated method to localise the right superficial femoral artery (SFA) and identify its boundary on magnetic resonance imaging (MRI) sequences without contrast medium injection is proposed. Some anatomical knowledge combined with the mathematical morphology is used to distinguish SFA from other vessels. Afterwards, the directional gradient, continuity and the local contrast are applied as features to identify the artery's boundary using dynamic programming. The accuracy analysis shows that the system has average unsigned errors 3.1 ± 3.1% on five sequences compared to experts' manual tracings.