膝骨性关节炎女性快速力量训练前后的肌肉MRI定量研究.pdf

国际医学放射学杂志 23 Jul鸦46穴4雪膝骨性关节炎女性快速力量训练前后的肌肉MRI定量研究屈瑾1，李文静2，孙焱2，展影1，雷新玮1【摘要】目的探讨女性膝骨性关节炎（）病人股四头肌结构、功能及KOA严重程度的相关性，研究快速力量训练后肌肉结构、功能及KOA症状的改变，及其可能机制。方法前瞻性招募21例女性KOA病人，平均年龄（62.84.0）岁，将其随机分为训练组（11例）和对照组（10例），训练组进行12周股四头肌快速力量训练。所有病人于基线及12周后进行定量MRI，测量股四头肌截面积（）和脂肪分数（），同时测量肌力（功率、峰力矩），评估下肢活动能力（爬梯功率）及KOA临床症状（WOMAC评分）。基线时行膝关节MRI检查并采用全器官MRI评分（WORMS评分）评估影像学退变程度。采用t检验、Mann-Whitney U检验或Wilcoxon符号秩检验比较基线时2组间以及每组中基线和随访间股四头肌结构、功能参数及KOA评价指标。采用Spearman或Pearson相关分析股四头肌特征与KOA评价指标以及股四头肌特征间的相关性。结果股四头肌CSA与爬梯功率呈正相关，与WOMAC评分呈负相关；股四头肌FF与WOMAC评分、WORMS评分呈正相关；股四头肌功率与WOMAC评分、WORMS评分呈负相关，与爬梯功率呈正相关；股四头肌峰力矩与WOMAC评分呈负相关，与爬梯功率呈正相关；股四头肌CSA与功率、峰力矩呈正相关，FF与功率、峰力矩呈负相关（均P0.05）。基线时2组间股四头肌结构、功能及WOMAC评分差异均无统计学意义（均P0.05）。训练组中随访较基线时股四头肌FF、WOMAC评分降低，爬梯功率增加（均P0.05）；对照组中基线和随访间各项指标的差异均无统计学意义（均P0.05）。结论股四头肌大小和脂肪浸润与女性KOA症状、肌力和下肢运动能力间存在相关性。快速力量训练能有效缓解KOA症状，改善下肢运动功能，减少肌肉脂肪浸润。【关键词】膝骨性关节炎；股四头肌；脂肪浸润；定量磁共振成像；肌力；快速力量训练；女性中图分类号：R684.3；R445.2文献标志码：AQuantitative MRI assessment of muscles in women with knee osteoarthritis before and after high-speed powertrainingQU Jin1,LI Wenjing2,SUN Yan2,ZHAN Ying1,LEI Xinwei1.1 Department of Radiology,Tianjin First CentralHospital,Tianjin 300192,China;2 Department of Radiology,Tianjin Childrens Hospital.Corresponding author:ZHAN Ying,E-mail:【Abstract】ObjectiveTo investigate the correlation between the quadriceps muscle structure,function,and severityof knee osteoarthritis（KOA）in female patients with KOA,and to study the changes in muscle structure,function,KOAsymptoms after high-speed power training,and explore the underlying mechanisms.MethodsA total of twenty-one femaleKOA patients with a mean age of(62.84.0)years were prospectively recruited and randomly assigned to either a traininggroup(11 patients)or a control group(10 patients).The training group underwent 12 weeks of quadriceps high-speed powertraining.Quantitative MRI was performed at baseline and after 12 weeks to measure quadriceps cross-sectional area(CSA)and fat fraction(FF).Muscle strength(power and peak torque),lower-limb motor function(stair climbing power),and clinicalsymptoms of KOA(WOMAC score)were also evaluated.Knee MRI was performed at baseline and the degree of radiographicdegeneration was assessed using the WORMS score.The t-test,Mann-Whitney U test,or Wilcoxon signed-rank test wereused to compare the quadriceps structural and functional parameters and KOA evaluation indexes between the two groups atbaseline,and between baseline and follow-up in each group.Spearman or Pearson correlation was used to analyze thecorrelation between quadriceps characteristics and KOA evaluation indexes and quadriceps characteristics.ResultsQuadriceps CSA showed a positive correlation with stair climbing power and a negative correlation with WOMAC scores.作者单位：1天津市第一中心医院放射科，天津300192；2天津市儿童医院放射科通信作者：展影，E-mail:基金项目：天津市卫生健康科技项目(KJ20099)DOI:10.19300/j.2023.L20074论 著：390-395；401390国际医学放射学杂志 23 Jul鸦46穴4雪Quadriceps FF exhibited a positive correlation with WOMAC scores and WORMS scores.Quadriceps power was negativelycorrelated with WOMAC scores and WORMS scores,and positively correlated with stair climbing power.Quadriceps peaktorque was negatively correlated with the WOMAC score and positively correlated with stair climbing power.Quadricepsfemoris CSA was positively correlated with power and peak torque,while FF was negatively correlated with power and peaktorque(all P0.05).There were no statistically significant differences in quadriceps structure,function,and WOMAC scoresbetween the training and control groups at baseline(all P0.05).In the training group,quadriceps FF and WOMAC scoresdecreased,and stair climbing power increased at follow-up compared to baseline(all P0.05).However,in the control group,no significant differences in any of the indicators were observed between baseline and follow-up(all P 50%面积，WORMS评分3分。D图，重组冠状面影像显示胫骨平台关节软骨多发骨囊肿（箭头），WORMS评分1分。ABCD392国际医学放射学杂志 23 Jul鸦46穴4雪表 12 组病人一般资料比较组别例数年龄/岁身高/cm体质量/kg BMI/（kg/m2）训练组1161.554.50159.455.9759.195.9923.363.04对照组1062.204.59157.974.4057.888.7223.253.87t-0.3300.7170.3970.077P0.7450.4820.6960.940表 2股四头肌结构、功能参数与 KOA 评价指标的相关性参数WOMAC评分WORMS评分爬梯功率/WrsPrsPrsP结构CSA-0.3920.010-0.1530.3330.3750.016FF0.5460.0010.3220.038-0.1970.218功能功率-0.3060.049-0.3370.0290.4520.003峰力矩-0.4530.003-0.2660.0890.4120.007表 3股四头肌结构与功能的相关性参数功率/W峰力矩/NmrPrPCSA0.4970.0010.5900.001FF-0.4680.002-0.4830.001组，每组10次，左右腿交替进行。1.7统计学方法采用SPSS 20.0软件分析数据。采用Shapiro-Wilk检验分析计量资料分布的正态性。符合正态分布的计量资料以平均值标准差（）表示，2组间比较采用独立样本t检验，每组中基线和随访比较采用配对t检验；非正态分布的计量资料以中位数M（P2，75）表示，2组间比较采用Mann-Whitney U检验，每组中基线和随访比较采用相关样本Wilcoxon符号秩检验。采用Spearman或Pearson相关分析股四头肌特征（结构、功能）参数与KOA评价指标间相关性，以及股四头肌特征间相关性。P0.05为差异有统计学意义。2结果2.12组病人一般资料比较训练组与对照组病人年龄、身高、体质量、BMI差异均无统计学意义（均），详见表1。2.2股四头肌特征参数与KOA评价指标的相关性基线时股四头肌特征参数包括结构：CSA为（2 720.98385.19）mm2，FF为5.99%2.60%；功能：平均股四头肌功率为（66.2618.78）W，峰力矩为（105.1426.73）Nm。KOA评价指标包括：中位WOMAC评分为29.50（21.00，46.00）分，WORMS评分为38.00（20.50，68.00）分，爬梯功率为157.13（133.56，212.37）W。2.2.1股四头肌结构、功能参数与KOA评价指标的相关性股四头肌CSA与爬梯功率呈正相关，与WOMAC评分呈负相关，与WORMS评分无相关性。股四头肌FF与WOMAC评分、WORMS评分呈正相关，与爬梯功率无相关性。股四头肌功率与WOMAC评分、WORMS评分呈负相关，与爬梯功率呈正相关。股四头肌峰力矩与WOMAC评分呈负相关，与爬梯功率呈正相关，与WORMS评分无相关性（表2）。2.2.2股四头肌结构与功能的相关性股四头肌CSA与功率、峰力矩呈正相关，FF与功率、峰力矩呈负相关（均P0.05），见表3。2.32组中基线及随访时股四头肌功能、结构参数及KOA评价指标比较基线时训练组和对照组间股四头肌功率（t=0.348，P=0.732）、峰力矩（t=-0.011，P=0.991）、CSA（t=-0.268，P=0.792）、FF（t=1.408，P=0.175）、爬梯功率（t=0.190，P=0.851）及WOMAC评分（Z=-0.670，P=0.503）的差异均无统计学意义（均P0.05）。训练组中随访较基线时股四头肌FF、WOMAC评分降低，爬梯功率增加（均P0.05），其余指标间差异均无统计学意义（均P0.05）；对照组中基线和随访间各项指标的差异均无统计学意义（均P0.05），详见表4。3讨论3.1股四头肌结构和功能与KOA发病关系及运动治疗KOA的病理生理机制膝关节稳定性主要依靠骨骼、韧带、关节囊的静力性平衡和膝周肌肉的动力性平衡，高质量的肌肉有利于维持膝关节动态稳定，膝周肌肉力量增加可降低KOA进展风险，保护膝关节。反之，股四头肌力量下降40%即可出现下蹲时膝关节不稳14。肌力下降使膝周肌腱生物力学性能降低，引起关节应力持续紊乱，加剧软骨磨损，最终导致KOA15。肌力与肌肉体积和肌肉质量有关。肌力下降可能由于肌肉体积减少(例如横截面积减小)或肌肉质量下降16。股四头肌萎缩可使膝关节活动缓冲能力下降，关节软骨压力负荷增高、超出代偿范围，导致关节软骨损伤、退变，最终引起膝关节不稳。肌肉脂肪浸润则可能导致肌肉质量下降3。脂肪浸润可能导致肌纤维体积减小，改变骨骼肌纤维方向，最终导致肌力下降。脂肪浸润还会降低胰岛素敏感性，影响骨骼肌正常合成蛋白质17。下肢运动可改善KOA症状，维持关节功能，改善肌肉性393国际医学放射学杂志 23 Jul鸦46穴4雪表 4不同时间阶段 2 组病人股四头肌结构、功能参数及 KOA 评价指标比较阶段训练组（n=11）功率/W峰力矩/NmCSA/mm2FF%爬梯功率/WWOMAC评分基线61.1818.7197.4524.552640.94424.187.453.80168.6736.5321.00（6.00，36.00）训练12周后65.1826.8398.2720.352678.67421.986.203.40200.9730.719.00（0.00，15.00）检验值-1.113a-0.136a-0.580a5.563a-3.294a-2.252bP0.2920.8940.5750.0010.0080.024阶段对照组（n=10）功率/W峰力矩/NmCSA/mm2FF%爬梯功率/WWOMAC评分基线58.1021.8597.6036.232686.13338.135.532.16165.3643.0728.00（19.50，33.00）训练12周后57.7013.6694.8029.662620.53349.815.611.92187.8756.1825.00（12.00，42.00）检验值0.100a0.407a2.074a-0.226a-2.065a-1.572bP0.9230.6930.0680.8270.0690.116a为t值，b为Z值。能，但有关运动如何为KOA病人提供镇痛作用的机制尚不清楚。3.2MRI检查评估股四头肌CSA及脂肪浸润的优势目前用于评估肌肉与脂肪的技术包括超声、双能X线吸收仪（dual-energy X-ray absorptionmetry,DXA）、CT及MRI。肌肉超声不能精准定量评估肌肉少量脂肪，对深部肌群作用有限。DXA不能精确测量单独肌肉的FF和肌肉量18。基于CT的肌肉脂肪定量技术辐射剂量较大，软组织分辨力有限。MR的mDIXON Quant技术采用7个峰值的脂肪峰模型进行水脂分离，多回波采集以进行数据拟合得到T2*mapping校正主磁场不均性，能精确定量肌肉脂肪含量，已应用于其他部位肌肉内脂肪定量测量19。3.3股四头肌特征参数与KOA评价指标的相关性3.3.1女性股四头肌肌力与KOA严重程度、下肢运动能力的相关性分析股四头肌功率反映肌肉快速产生力量的能力、关节活动能力、肌肉实际做功的能力，为运动速度的指标。股四头肌峰力矩是股四头肌最大等长强度数据，为在肌肉收缩过程中收缩力量最大的一点。本研究发现股四头肌峰力矩与WOMAC评分呈负相关，Kim等20也发现峰力矩与KOA症状有关，2个研究结果一致。同时本研究中股四头肌运动速度指标（功率）与KOA症状及MR影像学改变均有关。Hou等21认为伸肌力量减弱与KOA病人影像学结构性进展风险增加无关，本研究结果与其结果有差别。其原因可能是该研究影像学改变标志为MR软骨损伤和X线平片膝关节间隙变窄。而本研究中影像学评价完全基于WORMS评分，包含软骨、骨髓及半月板韧带等结构的病变。3.3.2女性股四头肌CSA、FF与肌力、KOA严重程度、下肢运动能力的相关性分析本研究显示股四头肌CSA与功率、峰力矩呈正相关。Veronese等16认为肌力下降可能是由肌肉体积减少(如CSA减小)或肌肉质量下降导致的，本研究结果与其一致。但Tsukada等22采用CT比较了35例女性KOA膝关节置换术前病人手术侧与对侧肌肉体积和肌力差异，认为肌力和肌肉体积无关，本研究结果与其不一致，可能原因是该研究病例均需行关节置换，而本研究入组病例K-L分级4，病情更轻。本研究显示股四头肌CSA与WOMAC评分呈负相关，与WORMS评分无相关性。Kemnitz等2认为女性KOA症状、大腿肌力均与伸肌CSA有关，本研究结果与其相符，但该研究还显示影像学退变也与伸肌CSA有关，本研究结果与其不一致。原因可能是Kemnitz等研究中入组病人平均BMI28 kg/m2，为肥胖病人，而本研究入组病例平均BMI24 kg/m2，在正常范围，肥胖和全身脂肪增多可能增加了脂肪在KOA病程中的炎性作用，而且超重使关节负荷增大，加重KOA病情。推测CSA与KOA症状、大腿肌力的相关性在BMI正常和超重/肥胖的女性病人中可能是有区别的。3.4女性基线及随访KOA症状严重程度、股四头肌肌力和结构比较分析Chen等23认为运动对KOA病人有中度镇痛作用，减轻功能障碍，改善股四头肌肌力24。本研究结果显示运动后症状、脂肪浸润及运动能力均有改善，但肌力无变化，可能是由于本研究训练时间不足或强度低所致。3.5股四头肌脂肪浸润、快速力量训练对女性膝关394国际医学放射学杂志 23 Jul鸦46穴4雪节功能及KOA症状的影响本研究中，股四头肌FF和KOA症状的相关性最高，WORMS评分只与功率和FF相关，推测FF与KOA症状及影像学退变的关系更为密切。其原因可能是脂肪本身是关节变性的介质17，脂肪组织能产生瘦素、趋化因子等脂肪因子及肿瘤坏死因子-、白细胞介素-1等炎性细胞因子，影响邻近细胞及靶组织的病理过程，参与了膝关节软骨退化、滑膜炎症和骨质破坏，对软骨细胞有促炎症和分解代谢的作用，因此脂肪浸润越严重疼痛越明显。本研究显示快速力量训练后，WOMAC总分和FF明显减低，余指标未见显著变化，提示快速力量训练最先改善KOA临床症状，降低肌肉脂肪浸润。推测运动后肌肉脂肪浸润和KOA症状变化趋势可能是一致的。运动使肌肉脂肪浸润减少，从而减轻KOA脂肪相关炎性反应可能是运动对KOA镇痛作用的机制之一。Ruhdorfer等9发现女性膝关节疼痛的发生伴随着伸肌力量的减少，而伸肌力量的减少并不在膝关节疼痛发生之前，本研究中，快速力量训练后，疼痛缓解时未发现肌力改变，肌力增加是否会发生在疼痛缓解之后则有待进一步研究。3.6局限性本研究存在一定局限性：（）样本量较小，且仅包括老年妇女，可能对结果有一定影响。（）运动训练及随访时间较短，强度较低，可能尚不足以引起肌肉功能和结构的变化。KOA相关远期变化，尤其是影像学改变有待进一步研究。综上，股四头肌大小和脂肪浸润与女性KOA症状、影像学退变程度、肌力和下肢运动能力间存在相关性。肌肉脂肪浸润可能是引起KOA症状的重要因素。运动能有效缓解KOA症状，改善下肢运动功能，减少肌肉脂肪浸润。参考文献：1MOHAJER B,DOLATSHAHI M,MORADI K,et 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