Three-dimensional finite element analysis of the stress of the patellofemoral joint after medial patellofemoral ligament reconstruction by different femoral reconstruction insertion points北大核心

BACKGROUND: There are many ways to reconstruct the patellofemoral ligament. Among them, the lateral insertion of the femur has a greater influence. At present, there are many ways to select femoral insertion points, but there are no conclusions. OBJECTIVE: Through the analysis of three-dimensional finite element software, the change of femoral reconstruction insertion position of medial patellofemoral ligament under different flexion states can analyze the stress of the patellofemoral joint to select a suitable femoral reconstruction insertion. METHODS: CT data of normal knee joints of adults were obtained to import Mimics, Geomagic and Soildworks software to extract molds and add ligaments. The femoral insertion points of the ligament were the midpoint between the medial epicondyle and the adductor tubercle, the medial epicondyle, the adductor tubercle, the projection point from the top of the femoral intercondylar fossa to the medial condyle and 10 mm below the adductor tubercle. The mold added with ligament was imported into the mechanical software Ansys to analyze the stress of patellofemoral joint after reconstruction of different femoral insertion points using finite element analysis. RESULTS AND CONCLUSION: (1) When the knee flexion was 0° and 30°, the stress of patellofemoral joint at any femoral insertion point of reconstructed medial patellofemoral ligament was greater than that at other angles (60°, 90°, and 120°). No matter which position was used as the femoral insertion point, when the knee joint was flexed more than 30°, there was basically no difference in the contact stress between the patellofemoral joints. (2) At 0° and 30° of knee flexion, the patellofemoral contact pressure was the largest at the point of the adductor tubercle, and the contact force at the midpoint between the medial epicondyle and the adductor tubercle was the smallest. When the knee was flexed 30°, the midpoint between the medial epicondyle and the adductor tubercle, the projection point from the top of the femoral intercondylar fossa to the medial condyle, and 10 mm below the adductor tubercle as the insertion point showed no significant difference in the contact stress. (3) Results indicate that when reconstructing medial patellofemoral ligament, the best choice of femoral lateral insertion point is the midpoint between the medial epicondyle and the adductor tubercle. This point can effectively restore the stability of knee joint and delay the degeneration of joint and cartilage. © 2023, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved.     

前后联合入路治疗腰骶椎结核31例临床观察

目的：探讨前路清除病灶、植骨联合后路经椎弓根钉棒系统治疗腰骶椎结核的临床疗效。方法选取该院2010年收治的31例腰骶椎结核患者为研究对象,病变部位为下腰椎及骶椎,术前抗结核治疗3周以上,采用后路椎弓根钉棒系统内固定,联合前路病灶清除、椎间植骨（髂骨）。术后卧床休息6～12周,持续使用抗结核药物12～18个月。结果随访12～43个月,有1例形成窦道,双侧形成脓肿,经再次手术切除窦道、清脓后愈合,植骨块无移位,结核病灶均愈合;13例有神经症状者基本恢复;31例术后随访未见椎体滑移,椎体高度、后突畸形矫正及椎体稳定性恢复满意,植骨于术后5～9个月骨性融合,无内固定松动、断裂。结论前后联合入路能彻底清除结核病灶和充分脊髓神经减压,矫正脊柱后凸畸形及坚强的三柱稳定性。     

腺苷预处理对脑缺血再灌注脑内星形胶质细胞的影响

目的 探讨腺苷预处理对脑缺血再灌注损伤脑内星形胶质细胞的影响.方法 制作大鼠脑缺血再灌注损伤模型.60只SD大鼠随机分为3组:假手术组(F组)、缺血再灌注组(IR组)、腺苷预处理组(AP组),再按缺血再灌注后不同时间把各组随机分成4个亚组,每组5只大鼠.应用Zeal Longa 5级评分法进行神经功能评分,并通过免疫组织化学法检测脑组织内胶质纤维酸性蛋白(glial fibrillary acid protein,GFAP)的表达.结果 (1)神经功能评分AP组各亚组均小于IR组各亚组(P均＜0.05),但大于F组各亚组(P均＜0.05);(2)F组GFAP阳性表达均较弱,IR组和AP组在脑缺血再灌注后2h开始出现GFAP阳性表达的细胞数量增多,AP组在6h、24h AP组GFAP阳性表达比IR组增强(P均＜0.05),在72h时AP组GFAP阳性表达较IR组减少(P＜0.05).结论 腺苷预处理能在大鼠局灶性脑缺血再灌注损伤早期阶段促进GFAP的表达,72h后抑制GFAP的过度表达.     

人工全髋关节置换术、动力髋部螺钉内固定术和股骨近端防旋髓内针内固定术治疗高龄不稳定型股骨转子间骨折对比研究

目的比较人工关节置换术、动力髋部螺钉(DHS)内固定术和股骨近端防旋髓内针(PFNA)内固定术治疗高龄不稳定型股骨转子间骨折的临床效果。方法 149例不稳定型股骨转子间骨折患者根据手术方式分为人工关节置换术组、DHS内固定组和PFNA内固定组,对3组患者的平均住院时间、手术时间、术中出血量、术后并发症、下床时间、髋关节功能(Harris评分)进行对比。结果 3组患者住院后均在5 d内手术,平均住院时间差异无统计学意义(P>0.05)。人工关节置换组和PFNA内固定组的手术时间、术中出血量明显低于DHS内固定组(P<0.05),而PF-NA内固定组与人工关节置换组手术时间差异无统计学意义(P>0.05),PFNA内固定组术中出血量低于人工关节置换组,差异有统计学意义(P<0.05)。平均下床时间人工关节置换组和PFNA内固定组明显短于DHS内固定组(P<0.05),而人工关节置换组明显短于PENA内固定组(P<0.05)。人工关节置换组和PFNA内固定组的Harris评分优良率明显高于DHS组,差异有统计学意义(P<0.05),人工关节置换组和PFNA组的Harris评分优良率差异无统计学意义(P>0.05)。结论人工关节置换术是治疗老年不稳定型股骨转子间骨折较好的选择。     

内侧副韧带不同程度损伤时膝关节的应力变化

背景：膝关节内侧副韧带损伤易导致继发性的半月板及软骨损伤,长期慢性损害会引起骨关节炎的发生。目前,关于内侧副韧带断裂所致半月板及关节软骨损伤的力学研究较少。目的：探讨膝关节内侧副韧带不同程度损伤对膝关节半月板及软骨生物力学的影响。方法：选择一名健康志愿者行膝关节CT和MRI检查,获取其影像资料,将扫描数据依次导入Mimics、Geomagic及Solidworks软件,经配准融合后建立正常膝关节三维模型,并在此基础上模拟出膝关节内侧副韧带不同程度损伤的模型,共分为4组,包括：(1)内侧副韧带完整;(2)内侧副韧带深层断裂;(3)内侧副韧带浅层断裂;(4)内侧副韧带完全断裂。最后导入Ansys软件,对膝关节施加3种模式载荷：(1)股骨顶端施加10 N·m外翻力矩;(2)股骨顶端施加4 N·m内旋力矩;(3)股骨顶端施加4 N·m外旋力矩。分析4组模型在不同载荷下对膝关节生物力学的影响。结果与结论：(1)在膝关节伸直位,对膝关节施加10 N·m外翻力矩时,内侧副韧带不同程度损伤后外侧半月板总体应力均增加,关节软骨应力变化不明显,并且当内侧副韧带浅层出现断裂后外侧半月板应力峰值明显增大;(2...     

腰椎间盘突出症CT影像学特征与症状严重程度关系及临床应用价值探讨

目的 探讨腰椎间盘突出症患者CT影像学特征与症状严重程度关系及对治疗决策的指导价值,以期为临床早期评估病情、制定治疗方案提供参考。方法 选取2019-12-08-2022-12-08新乡医学院第三附属医院收治的196例腰椎间盘突出症患者为研究对象。入院后均行CT检查,采用日本骨科协会腰痛评分量表(mJOA)对患者症状严重程度进行评估,比较不同症状严重程度患者CT影像学特征,logistic回归方程分析CT影像学特征与腰椎间盘突出症病情关系,受试者工作特征(ROC)曲线分析CT影像学特征对病情预测价值。治疗2周后评估疗效,并比较不同疗效患者CT影像学特征。结果 不同症状严重程度患者髓核突出类型(χ²=60.851,P<0.001)、突出形状(χ²=12.285,P=0.002)、髓核密度值(χ²=53.873,P<0.001)、髓核突出后与神经根关系(χ²=40.866,P<0.001)、髓核突出后对硬膜囊压迫程度(χ²=45.089,P<0.001)、额...     

多聚赖氨酸对脂肪来源干细胞三维立体条件下生物学特性的影响

背景:多聚赖氨酸可促进软骨细胞、表皮细胞的黏附、生长及增殖。目的:观察多聚赖氨酸对脂肪来源干细胞三维立体培养下生物学活性的影响。方法:采用流式细胞仪检测昆明小鼠脂肪来源干细胞表面CD29、CD34、CD44、CD45的表达,将脂肪来源干细胞分别与经多聚赖氨酸表面修饰的珊瑚羟基磷灰石或空白珊瑚羟基磷灰石体外复合培养。结果与结论:与空白珊瑚羟基磷灰石组比较,经多聚赖氨酸修饰的珊瑚羟基磷灰石上黏附的脂肪来源干细胞较空白珊瑚羟基磷灰石组多,并分泌较多细胞基质,复合培养2,4,8d的A值较明显增高(P<0.05);但经多聚赖氨酸修饰的珊瑚羟基磷灰石上黏附的脂肪来源干细胞碱性磷酸酶活性值升高不明显(P>0.05)。说明多聚赖氨酸能促进脂肪来源干细胞在珊瑚羟基磷灰石表面的黏附、生长和增殖,不影响脂肪来源干细胞向成骨细胞转化。     

腺苷预处理对大鼠缺血再灌注损伤的保护作用和机制

目的探讨腺苷预处理对脑缺血再灌注损伤的保护作用和机制。方法制作大鼠脑缺血再灌注损伤模型。将大鼠随机分为3组:假手术组(F组)、缺血再灌注组(IR组)、腺苷预处理组(AP组),用Zeal Longa 5级评分法进行神经功能评分;免疫组织化学法检测脑组织内碱性成纤维细胞因子(basic fibroblast growth factor,bFGF)的表达。结果 (1)神经功能评分AP组各亚组均小于IR组各亚组(P均<0.05),但大于F组各亚组(P均<0.05);(2)F组bFGF阳性表达极弱,IR组和AP组在脑缺血再灌注后2 h开始出现bFGF弱阳性表达并逐渐增强,24 h达高峰,72 h略有下降,6 h2、4 h、72 h时AP组bF-GF阳性表达较IR组相应各亚组增强(P<0.05)。结论 (1)腺苷预处理能减轻大鼠局灶性脑缺血再灌注损伤所引起的神经功能缺损症状;(2)腺苷预处理能增强中枢神经系统内bFGF的分泌,进而起到保护脑组织的作用。