膝关节软骨负荷运动前后磁共振T_2时间与容积变化研究

目的通过比较分析负荷运动前后膝关节软骨磁共振T2时间和软骨容积变化,探讨利用T2时间和容积变化反映负荷作用下软骨形态变化的可行性。方法选择20例健康志愿者,其中男性16例,女性4例;年龄为20.1~30.4岁,平均年龄25.7岁。在同等运动负荷前后进行软骨T2mapping序列成像,测量股骨内外侧髁、胫骨平台和髌软骨T2时间;以三维脂肪抑制快速扰相梯度回波(3D-FS-SPGR)序列扫描并采用最大信号强度投影法(MIP)重建后测量髌软骨及股骨髁软骨容积。比较负荷前后软骨T2时间变化、软骨容积差异,并分析软骨容积与T2时间变化间的相关性。结果运动前与运动后髌软骨T2时间最长,胫骨外侧平台最短;运动后不同部位软骨T2时间均降低(P=0.000),股骨内侧髁软骨下降幅度最大(t=-27.96,P=0.000);运动后膝关节软骨容积减小(P=0.000),股骨髁软骨容积变化程度(t=-86.71,P=0.000)大于髌软骨(t=-9.42,P=0.000);软骨容积与T2时间变化间无线性相关性(P0.05)。结论运动后膝关节软骨各部位T2时间和局部软骨容积均减少,但软骨容积与T2时间变化间无相关性;软骨T2mapping和软骨容积变化磁共振成像技术对评价负荷作用下软骨形态变化有一定的意义。     

正常膝关节软骨MRI T_1ρ序列表现初步研究

目的比较正常膝关节软骨MRIT1ρ和三维抑脂扰相梯度回波(3D-FS-SPGR)序列表现,研究T1ρ序列应用于软骨评估的可行性;评估软骨深层与浅层MRIT1ρ值的差异。方法选择经临床和影像确认的26例成年志愿者,其中男性11例,女性15例;年龄15~65岁,平均年龄31.69岁。分析其T1ρ和3D-FS-SPGR序列MRI成像表现。将膝关节软骨划分为髌软骨、髁间窝、股骨内外侧髁、胫骨内外侧平台6个部分。测量相同层面与位置的T1ρ第一回波和3D-FS-SPGR图像上软骨、软骨下骨、背景噪声的信号强度,比较两者的软骨与软骨下骨对比度比(CNR)和软骨信噪比(SNR)。选取6个部位软骨最厚处,把该处软骨厚度等分为深层和浅层,分别测量同像素感兴趣区(ROI)的T1ρ值。对以上数据进行配对t检验,以P0.05为差异有统计学意义。结果①膝关节T1ρ序列第一回波图像上的CNR均值和SNR均值均高于同一部位的3D-FSSPGR序列,CNR 29.88±10.00 vs 12.08±3.08(t=23.09,P=0.000),SNR 34.70±11.16 vs 14.18±3.46(t=23.929,P=0.000);②正常膝关节软骨深层均值(29.12±8.07)ms,浅层均值(43.23±6.78)ms,浅层T1ρ值显著高于深层表现(t=-24.687,P=0.000)。结论 T1ρ序列可用于软骨临床评估,浅层软骨胶原纤维排列较深层更为致密。     

基于MRI的成人正常膝关节软骨形态学测量

目的：了解正常膝关节软骨分布及股骨髁承重区的软骨厚度特点,为膝关节病变早期诊断和动态观察提供依据。方法：选取100名成人志愿者,男、女各50名,年龄20—30岁,平均25．3岁,膝关节均行MRI扫描。应用MIMICS软件对图像进行处理,在矢状位窗面上测量膝关节各部位软骨最大厚度。选择膝关节正常运动时的承重区,测量承重区域软骨的最大厚度并与其他区域进行比较。基于MRI图像行膝关节软骨三维重建,观察膝关节软骨的三维形态特征。结果：膝关节各部位的最大软骨厚度如下。胫骨外侧平台3．19mm,胫骨内侧平台3．07mm,股骨外侧髁2．93mm,股骨内侧髁3．19mm,股骨滑车软骨3．57mm,髌软骨3．75mm。不同性别与左右侧之间的软骨厚度差异无统计学意义（P〉0．05）。胫股关节承重区软骨厚度大于其他区域,有统计学差异（P〈0．05）。结论：成人正常膝关节各区域软骨厚度不同,胫股关节承重区软骨厚度大于非承重区域。基于MRI可以准确地测量膝关节各部软骨的厚度及重建膝关节软骨的三维形态。     

膝关节相关解剖结构测量在全膝关节置换术假体选择中的应用

目的 测量股骨、胫骨、髌骨的相关结构数据并归纳总结其特点,为研发符合我国人群的膝关节假体提供数据支持。方法 对正常膝关节标本中股骨髁上轴宽度、股骨后髁轴距等16项指标进行测量,分析股骨内侧髁前后径、股骨外侧髁前后径等指标与胫骨平台宽度的相关性。结果 共测得24例成人正常膝关节胫骨平台宽度为(70. 63±7. 27) mm。相关分析结果显示,股骨内侧髁前后径与胫骨平台宽度相关系数为0. 747,股骨外侧髁前后径与胫骨平台宽度相关系数为0. 634,胫骨内侧平台宽度与胫骨平台宽度相关系数为0. 729,胫骨外侧平台宽度与胫骨平台宽度相关系数为0. 899,胫骨内侧平台前后径与胫骨平台宽度相关系数为0. 809,胫骨外侧平台前后径与胫骨平台宽度相关系数为0. 651,髌骨宽度与胫骨平台宽度相关系数为0. 701。胫骨内侧平台、胫骨外侧平台及股骨髁上轴宽度对胫骨平台宽度有明显影响(F=226. 072,P 0. 001)。结论 股骨髁上轴宽度对胫骨平台宽度有影响,股骨内、外侧髁前后径、髌骨宽度与胫骨平台宽度呈正相关。通过他们之间的相关性有望对临床膝关节置换术假体选择等手术决策提供一定的参考。     

人体下肢长骨负重关节软骨下松质骨显微硬度分布特征的研究

目的探讨人体下肢长骨负重关节软骨下松质骨显微硬度的分布特征。方法选取3具年龄大于40岁的新鲜冰冻尸体标本,取出所有标本的右侧股骨和胫骨,分别于股骨头、股骨内髁、股骨外髁、胫骨内髁、胫骨外髁、胫骨远端距负重区关节软骨面1 cm处,垂直于下肢机械轴切下3 mm厚松质骨样本。使用维氏显微硬度测量系统测量骨组织显微硬度。比较不同标本、股骨与胫骨以及不同解剖部位软骨下松质骨的显微硬度差异,分析3具标本不同解剖部位软骨下松质骨显微硬度分布规律。结果共制成18个标本,行180次显微硬度测量。3具标本的下肢长骨负重关节软骨下松质骨的总体显微硬度值为20.3~47.3(36.0±5.7)HV,3具标本间差异无统计学意义(F=2.40,P=0.094)。股骨软骨下松质骨显微硬度小于胫骨,分别为(32.5±4.9)HV、(39.4±4.3)HV,差异有统计学意义(t=-10.02,P<0.001)。股骨头软骨下松质骨显微硬度为(32.9±4.6)HV,股骨内髁(35.1±3.9)HV、股骨外髁(29.7±4.7)HV、胫骨内髁(40.8±4.0)HV、胫骨外髁(36.8±4.2)HV、胫骨远端(40.7±3.6)HV,差异有统计学意义(F=33.28,P<0.001),其中股骨外髁显微硬度最低,胫骨内髁显微硬度最高,内髁均高于外髁。3具标本不同解剖部位软骨下骨的显微硬度分布规律相似。结论人体下肢长骨负重关节软骨下松质骨的显微硬度存在较大差异,胫骨软骨下松质骨显微硬度高于股骨,膝关节内侧间室硬度大于外侧间室。     

两种截骨顺序在全膝关节置换术中的应用比较

目的比较两种截骨顺序在全膝关节置换术（TKA）中的临床应用效果。方法回顾性分析2010年11月—2013年9月安徽医科大学附属省立医院行TKA的80例（80膝）膝关节骨性关节炎患者的临床资料,根据截骨顺序不同分成两组：观察组40膝,先行股骨截骨;对照组40膝,先行胫骨截骨。比较两组手术时间、术中胫骨内、外侧平台显露前后径范围、术后引流量、术前术后膝关节功能情况及HSS评分,并进行统计学分析。结果两组80例患者均获得随访6—14个月（平均11．3个月）。手术时间和术后引流量观察组分别为（53．4±13．8）min和（310±46）ml,对照组分别为（72．5±14．7）min和（425±40）ml,差异均有统计学意义（t值分别为5．99、11．93,P值均〈0．01）;胫骨外侧平台显露前后径观察组为（44．1±3．7）mm,对照组为（21．8±3．3）mm,差异有统计学意义（t=28．45,P〈0．01）;胫骨内侧平台显露前后径观察组为（45．6±3．5）mm,对照组为（43．5±4．2）mm,差异无统计学意义（t=2．43,P〉0．05）;观察组术后6周和12周的膝关节活动度分别为87．6°±14．2°和103．6°±7．4°,对照组分别为88．6°±13．6°和102．3°±6．8°,差异均无统计学意义（t值分别为0．32和0．82,P值均〉0．05）;观察组术后6周和12周的HSS评分分别为（90．12±8．6）分和（91．66±6．6）分,对照组术后6周和12周的HSS评分分别为（89．45±9．9）分和（91．87±7．5）分,差异均无统计学意义（t值分别为0．32和0．13,P值均〉0．05）。结论TKA中先行股骨截骨可以使胫骨的显露更为充分,起到简化手术操作,减少术中失血,缩短手术时间的作用。     

国人正常膝关节几何学参数测量及临床意义

目的：从几何学角度对国人正常膝关节的参数进行测量,探讨其与某些膝关节疾病的关系.方法：选取国人无明显损坏的干燥股骨标本和胫骨标本各83例,测量股骨长度（G）,股骨内、外侧髁宽度（G1、G2）,股骨髁间窝宽度（G3）及深度（G4）,股骨内、外侧髁倾斜角（GD1、GD2）,胫骨近端平台内、外侧后倾角（JD1、JD2）,胫骨近端内、外侧平台的前后经（J1、J3）、左右径（J2、J4）,胫骨近端平台髁间隆起的宽度（J5）及高度（J6）.测量后对有关参数进行统计学分析.结果：除J2对J4外,其余膝关节几何参数测量值之间配对检验其差异存在统计学意义（P＜0.05）.线性参数之间呈正相关关系（P＜0.05）,而线性参数与角度参数之间无相关关系（P＞0.05）.结论：根据所测得的结果,建立了国人正常膝关节几何参数的数据库,为某些膝关节疾病的病程分型与治疗提供参考.     

带肌或肌腱蒂腓骨上段转位代股骨,胫骨外侧髁的应用解剖

目的：为腓骨上段转位代股骨、胫骨外侧髁缺损,重建膝关节的功能提供解剖学基础。方法：解剖观测５４侧腓骨上段、股骨和胫骨外侧髁的形态。观测４４侧股二头肌腱和比目鱼肌起点的形态及血供。２侧下肢标本腓骨上段带股二头肌腱或比目鱼肌转位摹拟术式。结果：①腓骨关节面中部上下径２２．８±７．１ｍｍ;前后径２３．９±２．１ｍｍ;向内下斜６１．３°±６．４°;②股骨外侧髁关节面中部前后径３８．０±３．３ｍｍ;左右径２８．０±３．１ｍｍ;③胫骨外侧髁关节面中部前后径３７．１±２．７ｍｍ;左右径２４．６±２．８ｍｍ。结论：带股二头肌腱腓骨上段转位插入股骨内修复股骨外侧髁缺损,带比目鱼肌蒂腓骨上段转位插入胫骨内修复胫骨外侧髁缺损,术式设计具有可行性     

3.0 T MRI上正常成人膝关节软骨体积的定量测量及其临床意义

目的：提供正常成人膝关节关节软骨总体积的参考值,研究膝关节各部分软骨体积所占总体积的比重,探讨软骨体积与年龄、性别、身高、体重的关系.方法：选取无关节外伤及手术史、无膝关节痛的健康志愿者140例,分为7个年龄组,在3.0 T MR上使用水激发3D-MEDIC扫描序列对膝关节进行矢状位重复扫描.所获图像使用半自动软件OsiriX进行膝关节软骨的体积测量及三维重建.结果：膝关节软骨总体积的平均值为（18.16±4.36）cm^3,其中,股骨软骨体积最大,髌骨及胫骨外侧髁次之,胫骨内侧髁最小,所占平均比重分别为（58.1±3.3）%、（18.7±2.0）%、（13.3±1.8）%及（10.0±1.9）%,其中以胫骨内侧髁比重变化程度最大（CV=19%）.男性软骨平均体积大于女性,分别为（21.62±3.63）cm^3和（14.70±2.83）cm^3.膝关节软骨总体积大小以及各部分软骨体积与年龄的增长没有明显相关性（P＞0.05）.膝关节软骨总体积与身高及体重呈正相关（P＜0.001）.结论：关节软骨体积与年龄没有明显关系,与身高及体重呈正相关,因此在评估膝关节软骨病损的体积改变时需结合性别、身高及体重等因素综合评价.     

汉族成人膝关节软骨厚度变化规律的研究

目的借助软骨磁共振成像技术研究我国20～40岁成年人膝关节软骨厚度变化规律及其与年龄、体质量和性别等与骨关节炎有关的主要临床因素的相关性。方法对200例20～40岁间汉族正常志愿者进行磁共振(MR)膝关节软骨成像,序列包括:快速自旋回波加权(FSE T2W)、三维脂肪抑制扰相梯度回波(3D-FS-SPGR)和脂肪抑制质子加权(FS-PD)。分别记录股骨内侧髁、外侧髁、胫骨内侧平台、外侧平台和髌骨区5个区域软骨最大厚度。同时分别记录关节胫股角、身高、体质量并计算体质指数(BMI)。分析不同性别、BMI正常和超质量组、不同年龄段(以5岁年龄差为一年龄组)的膝关节各区域之间软骨厚度差异;采用多元方差分析不同年龄组软骨厚度总体差异;采用Sperman分析法对年龄、BMI、性别与软骨厚度的相关性进行分析。结果样本胫股角平均值为4.6°,不同组间差异无统计学意义(F=14.683,P=0.094);不同年龄组在股骨内侧髁和胫骨内、外侧平台软骨厚度方面存在显著性差异,以上区域软骨随年龄增大而变薄的趋势明显(F=2 968.790,P<0.001);软骨厚度与年龄具有较为明显的负相关性(r外侧平台=-0.352,r内侧平台=-0.475,r股骨内侧髁=-0.363)。不同性别间软骨平均厚度差异无统计学意义(t=0.4235,P=0.672)。超质量与体质量正常组间软骨平均厚度无显著差异(t=0.798,P=0.425);成年人股骨外侧髁软骨厚度与BMI负相关(r=-0.162,P=0.022),其余部位与BMI无相关性。结论在我国20～40岁正常成年人中,膝关节不同区域的软骨厚度差异显著且随年龄变化明显。该年龄段正常人膝关节软骨厚度与性别、体质量无相关性。     

Sodium relaxation times in the knee joint in vivo at 7T

The sodium concentration correlates directly with the concentration of proteoglycans (PG) in cartilage, the loss of which is an early signature of osteoarthritis (OA). As a result, quantitative sodium MRI is a promising technique for assessing the degradation of articular cartilage in patients with OA. Sodium relaxation times can also provide information on the degradation of cartilage: it has already been shown on bovine cartilage that T(1) and T2long are longer and T2short shorter when the PG concentration decreases. In this study, sodium T(1), T2*short and T2*long relaxation maps were measured in vivo at 7 T on 8 healthy volunteers and in 4 different regions of the cartilage in the knee joint. The patellar, femoro-tibial medial, lateral, and femoral condyle cartilage have an average T(1)~20 ms, but different T2*short (from 0.5 ms to 1.4 ms) and T2*long (from 11.4 ms to 14.8 ms). Statistically significant differences in T(1), T2*short and T2*long were observed between the different regions in cartilage (p < 10(- 5)). Statistical differences in T(1) were also observed between male and female data (p < 10(- 5)). These relaxation times measurements can further be applied as correction factors for sodium concentration maps in vivo and can also be useful as complementary information to quantitative sodium MRI in the quest for detecting early OA. These measurements were done on low resolution sodium images in order to acquire sufficient quality data for fitting (5 images for T(1) and 9 images for T2*) while keeping the total time of acquisition of the data reasonable for the volunteer's comfort (1 h 15 min).     

Individual and cumulative measures of knee joint load associate with T2 relaxation times of knee cartilage in young,uninjured individuals: A pilot study

BackgroundArticular cartilage structure and chondrocyte health are sensitive and reliant on dynamic joint loading during activities. The purpose of this pilot study was to determine the association between measures of individual and cumulative knee joint loading with T2 relaxation times in the knee cartilage of young individuals without knee injury.MethodsTwelve participants (17–30 years old) without history of knee injury or surgery completed MRI, physical activity (PA), and biomechanical gait testing. T2 relaxation times were calculated in the cartilage within the patella and lateral and medial compartments. Accelerometry was used to measure mean daily step counts, minutes of PA, and % sedentary time over 7 days. Vertical ground reaction force, external knee joint moments and peak knee flexion angle were measured during stance phase of gait using three-dimensional motion capture. Cumulative knee joint loading was calculated as daily step count by external knee joint moment impulse. The relationship between measures of knee joint loading and T2 relaxation times was assessed using Pearson correlations.ResultsHigher T2 relaxation times in the femoral and tibial cartilage were consistently correlated to greater body mass, daily step counts, moderate and vigorous PA, and peak knee joint moments (r = 0.10–0.84). Greater cumulative knee flexion and adduction loading was associated with higher T2 relaxation times in the femoral and tibial cartilage (r = 0.16–0.65).ConclusionPreliminary findings suggest that individual loading factors and cumulative knee joint loading are associated with higher T2 relaxation times in the articular cartilage of young, healthy knees.     

Associations between the properties of the cartilage matrix and findings from quantitative MRI in human osteoarthritic cartilage of the knee

The aim of this study was to investigate the associations between the properties of the cartilage matrix and the results of T2 mapping and delayed gadolinium-enhanced magnetic resonance imaging (dGEMRIC) in human knee osteoarthritic cartilage. Osteochondral samples were harvested from the middle part of the femoral condyle and tibial plateaus of 20 patients with knee osteoarthritis (OA) during total knee arthroplasty. Sagittal T2 mapping, T1pre, and T1Gd were performed using 7.0T magnetic resonance imaging (MRI). Gycosaminoglycan (GAG) distribution was evaluated by OARSI, collagen anisotropy was assessed by polarized light microscopy (PLM), and biochemical analyses measured water, GAG, and collagen content. Associations between properties of the cartilage matrix and T2 and ΔR1 (1/T1Gd-1/T1pre) values were explored using correlation analysis. T2 and ΔR1 values were significantly correlated with the degree of cartilage degeneration (OARSI grade; Ρ = 0.53 and 0.77). T2 values were significantly correlated with water content (r = 0.69; P < 0.001), GAG content (r = -0.43; P < 0.001), and PLM grade (r = 0.47; P < 0.001), but not with collagen content (r = -0.02; P = 0.110). ΔR1 values were significantly correlated with GAG content (r = -0.84; P < 0.001) and PLM grade (r = 0.41; P < 0.001). Taken together, T2 mapping and dGEMRIC results were correlated with the properties of the cartilage matrix in human knee osteoarthritic cartilage. Combination T2 mapping and dGEMRIC represents a potential non-invasive monitoring technique to detect the progress of knee OA.     

SOX trio decrease in the articular cartilage with the advancement of osteoarthritis

SOX trio (SOX-5, SOX-6, and SOX-9) maintain the chondrocytic phenotypes and are vital for chondrogenesis in embryonic development. The purpose of this study is to investigate the change in the expression of SOX trio with the advancement of osteoarthritis (OA) in human articular cartilage (AC). Human OA samples from eight patients were obtained from the distal femoral condyles during total knee arthroplasty. Minimally OA cartilage taken from areas with no obvious surface defects on lateral condyles was compared with advanced OA cartilage obtained from areas within 1 cm of overt lesion located on medial condyle surface. SOX-5, SOX-6, and SOX-9 gene expressions significantly decreased by 41% (p = 0.047), 46% (p = 0.047), and 56% (p = 0.029) in advanced OA area compared with the minimally OA area. There was a significant decrease in aggrecan and type II collagen (COL2A1) gene expressions by 73% (p = 0.029) and 65% (p = 0.029), respectively, in advanced OA area compared with the minimally OA area. From Western blotting and immunohistochemistry, SOX-5, SOX-6, SOX-9, type II collagen, and aggrecan protein expressions also significantly decreased in advanced OA cartilage compared with minimally OA cartilage. DNA methylation study of SOX-9 promoter regions revealed no difference in the epigenetic status between the two areas. It is concluded that SOX trio gene and protein decreased with advancement of OA in human articular cartilage.     

国人膝关节面的应用解剖学观测

目的观测国人膝关节的相关形态学指标,为膝关节损伤修复和关节重建等提供解剖学依据。方法利用游标卡尺、求积仪等仪器对43具成人出土骨骼的完整膝关节进行形态学测量。结果膝关节面积测量：胫骨内侧髁关节面面积左侧（6.93±1.56）cm^2,右侧（7.08±1.51）cm^2;胫骨外侧髁关节面面积左侧（7.61±0.97）cm^2,右侧（7.74±0.64）cm^2;股骨内侧髁关节面面积左侧（21.66±3.22）cm^2,右侧（21.12±1.86）cm^2;股骨外侧髁关节面面积左侧（24.02±3.97）cm^2,右侧（24.02±3.97）cm^2;髌骨关节面面积左侧（5.24±1.19）cm^2,右侧（6.20±1.08）cm^2。胫骨髁间隆起测量：高度左侧（1.08±0.27）cm,右侧（0.89±0.09）cm;宽度左侧（1.33±0.24）cm,右侧（1.21±0.04）cm。股骨髁间窝测量：深度左侧（2.26±0.29）cm,右侧（2.30±0.18）cm;宽度左侧（1.94±0.12）cm,右侧（1.88±0.16）cm。结论膝关节损伤修复、关节重建等均应以膝关节的形态学为依据方能达到良好的治疗效果。     

Intra-operative navigation of knee kinematics and the influence of osteoarthritis

Intra-operative assessment of knee kinematics should optimise implantation of total knee arthroplasties. The purpose of this work was to validate the data delivered by an adapted navigation system in 10 healthy cadaver knees and to investigate the kinematics of 10 osteoarthritic (OA) knees in patients undergoing total knee replacement. The system displayed the magnitude of axial rotation, the position of the instantaneous centre of axial rotation and the displacements of the condyles. Successive cycles from full extension to 140° of flexion in the same knee produced a mean external rotation of 20° ± 10°, which was correlated to knee flexion (r=0.6 ± 0.2 in healthy knees, r=0.8 ± 0.2 in OA knees). The centre of axial rotation migrated posteriorly an average of 8.2mm in both groups. The posterior displacements were 4 mm ± 5 mm in healthy and 5 mm ± 6 mm in OA knees for the medial condyle, and 21 mm ± 9 mm in healthy and 21 mm ± 10 mm in OA knees for the lateral condyle. The medial condyle lifted off beyond 110° of flexion. Results in healthy knees were consistent with those reported in the current literature. The kinematics of healthy and of OA knees with an intact anterior cruciate ligament did not differ significantly.