Standing Versus Supine Radiographs to Evaluate Femoral Head Penetration in the Polyethylene Liner After Total Hip Arthroplasty

The linear penetration rates for ceramic femoral heads on conventional and highly cross-linked polyethylene were measured and compared with radiographs taken in the standing and supine position taken three weeks postoperatively and at final follow-up. Seventy-five patients (83 hips) with conventional polyethylene (group-1) and two hundred and seventy five patients (300 hips) with highly cross-linked polyethylene (group-2) were studied. Follow-up periods were 14.5 years in group-1 and 8.6 years in group-2. The average penetration rates in group-1 were 0.17 mm/year in supine position and 0.18 mm/year in standing position (P < 0.05). On the other hand, the rates in group-2 were 0.03 mm/year and 0.04 mm/year respectively (P < 0.05). Although there were statistical differences between groups, 0.01 mm differences are probably not clinically relevant.     

沙利度胺联合三维适形放射治疗中晚期肝癌

目的:探讨沙利度胺(TLD)联合三维适形放射(3-DCRT)治疗中晚期原发性肝癌的临床疗效及不良反应。方法:60例患者分观察组和对照组各30例,观察组在3-DCRT基础上加口服TLD,对照组不用TLD。结果:近期疗效显示观察组肿瘤完全缓解(CR)4例,部分缓解(PR)22例,无变化(NC)3例,进展(PD)1例,总有效率为86.7%(P0.05)。两组未见严重不良反应发生。随访3年,观察组1、2、3年生存率分别为73.3%、56.7%、36.7%;对照组为46.7%、30.0%、13.3%(P0.05)。结论:应用TLD与3-DCRT联合治疗中晚期原发性肝癌疗效明显,不良反应轻,具有一定的临床应用价值。     

Trabecular Homogeneity Index Derived From Plain Radiograph to Evaluate Bone Quality

Radiographic texture analysis has been developed lately to improve the assessment of bone architecture as a determinant of bone quality. We validate here an algorithm for the evaluation of trabecular homogeneity index (HI) in the proximal femur from hip radiographs, with a focus on the impact of the principal compressive system of the trabecular bone, and evaluate its correlation with femoral strength, bone mineral density (BMD), and volumetric trabecular structure parameters. A semiautomatic custom‐made algorithm was applied to calculate the HI in the femoral neck and trochanteric areas from radiographs of 178 femoral bone specimens (mean age 79.3 ± 10.4 years). Corresponding neck region was selected in CT scans to calculate volumetric parameters of trabecular structure. The site‐specific BMDs were assessed from dual‐energy X‐ray absorptiometry (DXA), and the femoral strength was experimentally tested in side‐impact configuration. Regression analysis was performed between the HI and biomechanical femoral strength, BMD, and volumetric parameters. The correlation between HI and failure load was R² = 0.50; this result was improved to R² = 0.58 for cervical fractures alone. The discrimination of bones with high risk of fractures (load <3000 N) was similar for HI and BMD (AUC = 0.87). Regression analysis between the HIs versus site‐specific BMDs yielded R² = 0.66 in neck area, R² = 0.60 in trochanteric area, and an overall of R² = 0.66 for the total hip. Neck HI and BMD correlated significantly with volumetric structure parameters. We present here a method to assess HI that can explain 50% of an experimental failure load and determines bones with high fracture risk with similar accuracy as BMD. The HI also had good correlation with DXA and computed tomography–derived data. © 2013 American Society for Bone and Mineral Research.     

Digital Assessment of the Implantation Angle of Proximal Femoral Nail Antirotation Helical Blade Using CT Three-dimensional Reconstruction

Objectives: To facilitate simple and safe manipulation during proximal femoral nail antirotation (PFNA) operation, we studied the range of safe implantation angle of the helical blade of the PFNA system by using a digital-based three-dimensional reconstruction model of CT images. Methods: Thirty-five healthy volunteers were recruited. Original multilayer helical CT scan data of the left femur were collected and imported into Mimics software. Anatomic features of the femur, including the safe implantation angle, anterior and posterior angle, were measured. Differences in each angle between male and female subjects were compared using Student's t test, and the determinants of each angle were analyzed by linear regression. Results: The mean safe implantation angle was 30.09° ± 4.73°, the mean anterior angle was 15.82° ± 2.07°, and the mean posterior angle was 14.27° ± 3.19°. All the three angles were greater in males than females (P < 0.05). Neck shaft angle and the diameter of the femoral neck and head were linearly correlated with the safe implantation angle, the anterior and posterior angle, respectively. Femoral neck diameter was a significant determinant of the safe implantation angle and posterior angle, respectively. Moreover, femoral neck diameter and femoral head diameter were significant determinants of the anterior angle. Conclusions: The study has introduced and delineated a novel parameter, the safe implantation angle, for FPNA surgery, which may help orthopedic surgeons in deciding a safe range of PFNA operation and improve the accuracy of PFNA helical blade implantation.     

三维钉板系统的研制及固定股骨粗隆间骨折的生物力学比较研究

目的 观察自行研制的三维钉板系统(static three dimensional screw plate system,STDSP),固定股骨粗隆间骨折时的生物力学性能.方法 采用配对分组的方法,体外利用股骨粗隆间骨折模型,将自行研制的三维钉板系统与DHS及角钢板作对比研究,分析三者在抗轴压及抗扭转的生物力学性能.结果 抗压时股骨头下降的位移STDSP组小于DHS组和AP组,P＜0.01和P＜0.05.骨折线张开位移STDSP组与DHS组无明显差异,P＞0.05;AP组骨折线张开位移明显大于STDSP组,P＜0.001.在扭转载荷下,相同扭转角STDSP组扭矩明显大于DHS组和AP组,P＜0.01.结论 STDSP为多钉与侧方钢板联合结构,可在三维空间上进行固定,应用于股骨粗隆间骨折固定时具有较优良的抗轴压、抗扭转等性能.     

实时三维心脏超声引导下右胸切口与传统开胸体外循环下房间隔缺损手术效果的比较

目的 比较实时三维心脏超声（RT-3DE）引导非体外循环（CPB）下经右胸小切口房间隔缺损（ASD）封堵与传统CPB下心内直视修补的手术效果。 方法 2009年4月至2012年4月在红河州第一人民医院接受手术的继发孔型ASD患者64例,按手术方式分为Ａ组和B组。A组35例接受传统CPB心内直视修补,男20例、女15例,年龄12～56 （16.4±4.0） 岁;B组29例接受RT-3DE 引导非体外循环（CPB）下经右胸小切口ASD封堵,男13例、女16例,年龄15～50 （18.5±0.2） 岁。比较2组手术时间、术后呼吸机辅助时间、术后住院时间、胸腔引流量、死亡、并发症等指标及随访结果。 结果 B组手术时间［（110.47±35.90） min vs. （159.32±20.60） min］、术后呼吸机辅助时间［（10.40±22.30） h vs. （16.40±12.20） h］、胸腔引流量［（106.71±85.20） ml vs. （146.70±75.63） ml］及术后住院时间［（4.0±1.0） d vs. （7.0±1.0） d］ 均较A组显著减少（P＜0.05）。A组死亡1例,发生术后并发症7例;B组无1例死亡,发生术后并发症3例。A组术后并发症总发生率高于B组（20.0% vs. 10.3%,P＜0.05）。 结论 对手术适应证明确的患者,RT-3DE引导非CPB下右胸小切口ASD封堵的微创外科手术优势明显。     

The Permissive Safe Angle of the Tibial Tunnel in Transtibial Posterior Cruciate Ligament Reconstruction: A Three‐Dimensional Simulation Study

ObjectiveTo determine the permissive safe angle (PSA) of the tibial tunnel in transtibial posterior cruciate ligament (PCL) reconstruction based on a three‐dimensional (3D) simulation study.MethodsThis was a computer simulation study of transtibial PCL reconstruction using 3D knee models. CT images of 90 normal knee joints from 2017 to 2020 were collected in this study, and 3D knee models were established based on CT data. The tunnel approaches were subdivided into the anterior 1/3 of the anteromedial tibia (T1), middle 1/2 of the anteromedial tibia (T2), the tibial crest (T3), anterior 1/3 of the anterolateral tibia (T4), middle 1/2 of the anterolateral tibia (T5). Five tibial tunnels (T1–T5) were simulated on the 3D knee models. The PSAs, in different tibial tunnel approaches were measured, and subgroup analyses of sex, age and height were also carried out.ResultsThe mean PSAs of the tibial tunnels with 5 different approaches (T1–T5) were 58.49° ± 6.82°, 61.14° ± 6.69°, 56.12° ± 7.53°, 52.01° ± 8.89° and 49.90° ± 10.53°, respectively. The differences of the mean PSAs between the anteromedial and anterolateral approaches were significant (P < 0.05). However, there was no significant difference of the mean PSA value between the two anteromedial tibial tunnel approaches (T1–T2) (P > 0.05), as well as between the two anterolateral tibial tunnel approaches (T4–T5). The patient''s anthropomorphic characteristics of sex, age, and height were not associated with the PSAs.ConclusionsThe PSA varied with the anteromedial, tibial crest and anterolateral approaches for transtibial PCL reconstruction, and surgeons should limit the PCL drill guide by referring to the specific PSA for different surgical approaches.     

Relevance of bioreactors and whole tissue cultures for the translation of new therapies to humans

The purpose of this review is to provide a brief overview of bioreactor‐based culture systems as alternatives to conventional two‐ and three‐dimensional counterparts. The role, challenges, and future aspirations of bioreactors in the musculoskeletal field (e.g., cartilage, intervertebral disc, tendon, and bone) are discussed. Bioreactors, by recapitulating physiological processes, can be used effectively as part of the initial in vitro screening, reducing that way the number of animal required for preclinical assessment, complying with the 3R principles and, in most cases, allowing working with human tissues. The clinical significance of bioreactors is that, by providing more physiologically relevant conditions to customarily used two‐ and three‐dimensional cultures, they hold the potential to provide a testing platform that is more predictable of a whole tissue response, thereby facilitating the screening of treatments before the initiation of clinical trials. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:10–21, 2018.     

腭裂患者语音评价系列研究(三)--应用普通话单元音三维声学模型评价腭裂儿童元音特征的初步研究

目的：应用普通话单元音三维声学模型，评价腭裂儿童的音声问题。方法：利用语音声学分析软件SA1.5对37名腭裂术前儿童进行单元音[a]、[o]、[e]、[I]、[u]、[u]的语音频谱分析，测得共振峰频率。以三个共振频率的算术标度分别为x、y、z轴坐标，利用数学软件Matlab5.3建立腭裂儿童三维声学模型并与正常儿童模型进行比较。结果：正常模型的形态典型，立体感强；腭裂儿童由于存在共振峰频率的漂移，除[a]音以外，各元音的空间位置均发生了很大变化，三维模型缺乏空间感。正常与腭裂模型差别明显。结论：三维声学模型直观、全面而客观地反映了腭裂儿童音声特点，可实现对腭裂儿童单元音客观评价。