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1.
This research study was designed to evaluate the aesthetic consequences of different dorsal augmentation techniques using diced cartilage on dorsal width and projection in rhinoplasty. Patients were assigned to three groups based on the dorsal augmentation technique used: diced cartilage wrapped in fascia (DCIF), free diced cartilage under fascia (DCUF), and free diced cartilage without fascia (FDC). Dorsal projection and dorsal aesthetic width were measured at two levels using pre- and postoperative photographs. A total of 98 patients were included in the study. DCIF was used in 51 patients, FDC in 27 patients, and DCUF in 20 patients. There was no significant difference in nasion projection, rhinion projection, or width of the dorsal aesthetic lines at the intercanthal and keystone levels among these groups. Significantly greater nasion and rhinion projection was observed with DCIF in thin-skinned patients followed-up for 6–12 months (nasion, P = 0.028; rhinion P = 0.039) but not at>12 months. Two patients with a graft infection and one with graft malposition were encountered in the DCIF group. Experience from this study suggests that the application of FDC prevents such complications without sacrificing the dorsal augmentation and that DCIF is a better choice for more severe deformities.  相似文献   
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BackgroundSurgical planning of posterior referencing total knee arthroplasty (TKA) using computed tomography (CT) might lead to over-rotation of the femoral component because CT could not detect cartilage thickness of the posterior femoral condyle. The purpose of this study was to examine the rotational alignment difference of the femoral component between magnetic resonance imaging (MRI) and CT.MethodsFor elderly varus osteoarthritic patients, 66 varus osteoarthritic knee patients that underwent primary TKA were selected. Twenty-seven young patients who underwent primary anterior cruciate ligament reconstruction were selected as control. After the transepicondylar axis (CEA), the surgical epicondylar axis (SEA) and the posterior femoral condylar line (PCL) were drawn on CT and on MRI at the same angles as CT. Then, the practical PCL was drawn on MRI considering the cartilage thickness (the cartilage PCL). The angle between the SEA and the cartilage PCL (the cartilage posterior condylar angle (PCA)) was measured as preoperative planning. To investigate the accuracy of preoperative MRI measurement, the cartilage thickness on posterior femoral condyles was directly measured during TKA.ResultsThe cartilage PCA for varus osteoarthritic patients averaged 1.3 ± 1.3°. The cartilage PCA was 1.8 ± 1.0° significantly smaller than the bone PCA (the PCA measured on CT). Meanwhile, the cartilage PCA was 0.2 ± 0.4° significantly larger than the bone PCA in young people. The preoperative angle measurement on MRI strongly correlated with the direct measurement of cartilage thickness during TKA.ConclusionThere was 1.8° of divergence between MRI and CT in varus osteoarthritic patients due to cartilage degeneration of the medial femoral condyle. Cartilage assessment using MRI was useful for femoral component rotational alignment.  相似文献   
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作为半刚性的、无血管和神经的结缔组织,软骨具有承重、应力缓冲和辅助运动等多种生理功能。软骨固有的修复能力差,损伤不易逆转且治疗难度大。近年来,大量研究结果显示适宜的电磁辐射对软骨细胞形态的维持及其细胞因子的分泌、软骨细胞外基质的稳态以及骨关节炎的治疗等都具有积极的意义。笔者就电磁辐射对软骨的生物学效应及其可能的作用机制作一综述。  相似文献   
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BackgroundPatellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography.PurposeTo report the postoperative outcomes of patients age 21 and younger treated with particulated juvenile allograft cartilage (PJAC) for full-thickness cartilaginous defects of the patellofemoral joint. The primary aim was to report surgical outcomes and complication rates, as well as return to sport activity. A secondary aim was to provide objective scores of defect restoration by magnetic resonance imaging (MRI) assessment.MethodsA retrospective review of all PJAC cases conducted between 2012 and 2019 at a single tertiary care urban musculoskeletal institution was conducted. Patients 21 years old or younger with minimum clinical follow up of 1 year and postoperative MRI at a minimum of 6 months were included. Cartilage restoration by MRI was independently assessed using the International Cartilage Repair Society’s (ICRS) standardized system.ResultsThirty four patients, 36 knees, were included, with mean age 16.1 ± 3.1 years old. Return to sport rate among patients who participated in a sport preoperatively was 100%. On independent MRI assessment, two thirds of defects achieved an overall grade of normal or nearly normal, while 28 patients (78%) had majority defect fill. Primary graft failure occurred in two cases and one patient experienced a surgical complication.ConclusionRestoration of patellofemoral chondral defects in young patients with particulated juvenile allograft results in satisfactory short-term outcomes and postoperative MRI appearance, along with high rates of return to sport and low rate of complications and graft failure.What is known about the subject: Patellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography. Several cartilage restoration techniques are available, but these rarely achieve the same mechanical properties as native hyaline cartilage. PJAC is a cell-based technique that has demonstrated promise since its introduction in 2007.What this study adds to existing knowledge: This series of patients adds the largest single cohort of pediatric and adolescent patients who receive PJAC for defects of the patellofemoral joint. Surgeons treating patients in this age group should be aware of every technique, and their respective outcomes.  相似文献   
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目的探讨髌股关节软骨退变程度对内侧活动平台单髁置换术短期疗效的影响。 方法回顾性分析2017年1月至2018年12月在深圳市人民医院因前内侧骨关节炎行内侧活动平台单髁置换或全膝关节置换术的75例患者资料,依据术中探查髌股关节软骨退变情况分为无退变单髁组(无退变组)、内侧退变单髁组(内侧退变组)、内外退变单髁组(内外退变组)和内外退变全膝组(全膝组)。单因素方差分析对比4组患者术前术后牛津大学膝关节评分(OKS)、美国特种外科医院(HSS)评分、骨关节炎指数(WOMAC)评分,并记录终末随访时有无假体松动、脱位、力线改变等情况。 结果所有患者获得随访,随访时间平均(36±10)个月。4组患者术后OKS评分、HSS评分、WOMAC评分较术前均有改善(F=18.555,P<0.001;F=5.867,P=0.001;F=22.671,P<0.001);术前术后OKS、HSS、WOMAC评分差值,无退变组与内侧退变组之间差异均无统计学意义(均为P>0.05),内外退变组与无退变组、内侧退变组相比,功能改善程度稍差(均为P<0.05),内外退变组与全膝组之间OKS、HSS、WOMAC评分差值差异无统计学意义(均为P>0.05)。所有病例于末次随访时无假体松动、脱位、力线改变。 结论内侧髌股关节软骨退变对内侧活动平台单髁置换术后疗效影响不大,但面对外侧髌股关节软骨退变时则需慎重,此时选择单髁或是全膝,需个性化考虑。  相似文献   
7.
目的观察脐带间充质干细胞分泌的外泌体对骨性关节炎模型大鼠疼痛行为、软骨修复及背根神经节(DRG)中转录激活因子3(ATF-3)及生长相关蛋白43(GAP-43)表达的影响, 并探讨外泌体治疗关节炎疼痛的可能机制。方法采用随机数字表法将54只雄性SD大鼠分为假手术组、模型组和外泌体组, 每组18只, 除假手术组外, 其余2组均于左后肢膝关节腔注射4 mg/50 μl单碘乙酸钠(MIA)建立疼痛模型, 假手术组大鼠关节腔注射50 μl生理盐水作为对照。造模14天后, 假手术组和模型组大鼠左后肢膝关节腔注射50 μl生理盐水, 外泌体组大鼠注射50 μl外泌体。于造模前1天、造模后第7、14天及给药后第7、14、28天对各组大鼠机械痛阈和热痛阈进行测定;于测试后取出相应时间点DRG, 采用免疫蛋白印迹法检测ATF-3及GAP-43表达情况;并取出相应时间点各组大鼠膝关节, 采用苏木素伊红(HE)染色检测软骨修复情况。结果与模型组比较, 外泌体组在给药后第7天时, 机械痛阈值及热痛阈值均明显增加, 直到给药后第28天时差异均具有统计学意义(P<0.05);DRG水平ATF-3蛋白表达显著...  相似文献   
8.
目的探讨运用鼻中隔软骨联合耳廓软骨构建鼻中隔延伸物复合体重置鼻尖位置和重塑鼻尖形态的可行性。方法 2018年9月至2019年10月,以中国医学科学院整形外科医院17例低鼻患者为研究对象,17例患者中男2例,女15例;年龄19~39岁,平均27岁。17例患者均为初次鼻整形病例。术中在全身麻醉下行鼻整形术。切取鼻中隔软骨作为鼻中隔延伸移植物延长鼻中隔尾端;切取自体耳廓软骨制备成:撑开移植物、鼻小柱支撑移植物、抗回缩移植物、帽状移植物,以加强支架的稳定性及抬高鼻尖,调整鼻尖形态。鼻背使用膨体材料充填。运用数字化面部扫描技术对术前术后鼻部结构进行测量。以SPSS 22统计软件对相关数据行配对t检验。结果术后平均随访6~12个月,平均7.6个月。17例患者均对术后鼻形态、鼻长度、鼻尖高度满意。鼻尖触感自然,无感染,无假体移位、皮瓣坏死,无耳廓变形等并发症。术后鼻长增加(3.60±0.77)mm、鼻尖高度增加(3.61± 0.64)mm;较术前差异有统计学意义(t值分别为-19.203、-23.132,P值均<0.001);鼻唇角较术前减小(3.40±2.11)°,差异有统计学意义(t=6.635,P<0.001)。结论运用鼻中隔软骨联合耳廓软骨构建鼻中隔延伸物复合体重置鼻尖位置和重塑鼻尖形态具有可行性。  相似文献   
9.
PurposeThe purpose of this study was to compare morphologic assessment and relaxometry of patellar hyaline cartilage between conventional sequences (fast spin-echo [FSE] T2-weighted fat-saturated and T2-mapping) and synthetic T2 short-TI inversion recovery (STIR) and T2 maps at 1.5 T magnetic resonance imaging (MRI).MethodThe MRI examinations of the knee obtained at 1.5 T in 49 consecutive patients were retrospectively studied. There were 21 men and 28 women with a mean age of 45 ± 17.7 (SD) years (range: 18–88 years). Conventional and synthetic acquisitions were performed, including T2-weighted fat-saturated and T2-mapping sequences. Two radiologists independently compared patellar cartilage T2-relaxation time on conventional T2-mapping and synthetic T2-mapping images. A third radiologist evaluated the patellar cartilage morphology on conventional and synthetic T2-weighted images. The presence of artifacts was also assessed. Interobserver agreement for quantitative variables was assessed using intraclass correlation coefficient (ICC).ResultsIn vitro, conventional and synthetic T2 maps yielded similar mean T2 values 58.5 ± 2.3 (SD) ms and 58.8 ± 2.6 (SD) ms, respectively (P = 0.414) and 6% lower than the expected experimental values (P = 0.038). Synthetic images allowed for a 15% reduction in examination time compared to conventional images. On conventional sequences, patellar chondropathy was identified in 35 patients (35/49; 71%) with a mean chondropathy grade of 4.8 ± 4.8 (SD). On synthetic images, 28 patients (28/49; 57%) were diagnosed with patellar chondropathy, with a significant 14% difference (P = 0.009) and lower chondropathy scores (3.7 ± 4.9 [SD]) compared to conventional images. Motion artifacts were more frequently observed on synthetic images (18%) than on conventional ones (6%). The interobserver agreement was excellent for both conventional and synthetic T2 maps (ICC > 0.83). Mean cartilage T2 values were significantly greater on synthetic images (36.2 ± 3.8 [SD] ms; range: 29-46 ms) relative to conventional T2 maps (31.8 ± 4.1 [SD] ms; range: 26-49 ms) (P < 0.0001).ConclusionDespite a decrease in examination duration, synthetic images convey lower diagnostic performance for chondropathy, greater prevalence of motion artifacts, and an overestimation of T2 values compared to conventional MRI sequences.  相似文献   
10.
目的:考察淫羊藿苷在治疗骨关节炎中的潜在价值,以及淫羊藿苷对核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)炎性小体和半胱天冬酶-1(Caspase-1)的调控作用。方法:本研究通过脂多糖(LPS)诱导大鼠膝关节软骨细胞建立体外骨关节炎模型,通过碘乙酸单钠处理SD大鼠建立体内骨关节炎模型。通过乳酸脱氢酶漏出实验检测细胞毒性,通过MTT实验检测细胞活力。通过qRT-PCR检测NLRP3 mRNA的表达,通过Western Blotting检测NLRP3、IL-1β、IL-18、MMP-1、MMP-13、Collagen Ⅱ、Caspase-1、ASC和GSDMD的蛋白表达。用免疫荧光法和免疫组化法检测软骨细胞和大鼠软骨中的NLRP3表达;番红O/固绿染色评价大鼠软骨病变。结果:与LPS组比较,LPS+ICA组LDH的漏出率、IL-1β、IL-18、MMP-1、MMP-13、NLRP3、Caspase-1、ASC和GSDMD的表达水平明显降低,而Collagen Ⅱ明显升高(P<0.05)。与LPS+ICA+pcDNA3.1-NC组比较,LPS+ICA+pcDNA3.1-NLRP3组的乳酸脱氢酶漏出率及NLRP3炎性小体相关蛋白表达水平明显升高(P<0.05)。与对照组比较,OA组大鼠软骨组织中NLRP3阳性细胞数量显著增加,而OA+ICA组的NLRP3阳性细胞数量明显降低(P<0.05)。与OA组比较,OA+ICA组的NRLP3、IL-1β、IL-18、MMP-1、MMP-13、Caspase-1、ASC和GSDMD的蛋白表达水平明显降低,而Collagen的蛋白表达水平明显升高(P<0.05)。结论:淫羊藿苷通过抑制NLRP3和Caspase-1信号转导来抑制脂多糖诱导的软骨细胞损伤和细胞焦亡,从而减轻大鼠骨关节炎。  相似文献   
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