【作者】 任伟民；

【导师】 谷贵山；

【作者基本信息】 吉林大学 ， 外科学， 2017， 博士

【摘要】 股骨滑车发育不良是指股骨滑车沟前部几何形态和深度存在的解剖学异常。股骨滑车是构成髌股关节的主要结构之一,该结构异常可直接导致髌骨与股骨滑车近端不能稳定衔接,引起髌股关节解剖结构异常,影响该关节的稳定性,加速关节磨损,诱发髌股关节炎。髌股关节炎是一种以膝关节疼痛、功能障碍为主要临床表现的膝关节疾病,具有很高的发病率。随着人口老龄化,髌股关节炎的发病几率逐渐上升,髌股关节炎的预防和治疗,将是一个漫长的、具有较高社会负担、经济负担的过程。因此,如何从根本上解决髌股关节炎的发生应该是目前研究的热点。本研究的目的,是将股骨滑车发育不良作为导致髌股关节炎的一种独立因素进行研究,在建立三维有限元模型的基础上,系统阐述其致病的生物力学基础,根据所研究的结论,从力学角度模拟、探讨髌股关节炎的治疗方法,最后分析相关的临床资料,探讨滑车发育不良致结髌股关节炎的发病率,分型以及治疗方法。第一部分:股骨滑车发育不良的生物力学基础。本研究利用有限元方法建立股骨滑车发育不良的模型,分析加载过程中关节骨骼及软骨的应力变化,并施加虚拟手术治疗,术后再次对比分析关节周围的应变及应力情况,以明确股骨滑车发育不良的生物力学基础特性。通过影像扫描获取明确诊断C型股骨滑车发育不良病人的MRI及CT影像资料,利用有限元分析技术,在三维逆向工程软件MIMICS中建立膝关节三维模型,使用Geomagic Studio软件对已建立的模型进行优化、修饰,导入Abaqus软件,赋予模型各个部件材料属性,给予力学加载。首先分析该模型各屈曲角度下(30°,60°,90°,120°)股骨外髁软骨力学性能,对股骨、胫骨及软骨应力、应变分析;然后对所建立的模型进行虚拟手术(内侧髌股韧带重建术),并分析相对应屈曲角度股骨外髁软骨力学性能、应力及应变情况。结果表明,在股骨滑车发育不良的膝关节中,屈曲30度时髌骨与股骨外髁软骨接触的位置应力、分布比较均匀,未出现明显的应力集中现象。但随着屈曲角度的增加(60°-120°),股骨外髁软骨与髌骨接触位置的应力集中现象逐渐明显,易导致髌股关节炎的发生。虚拟手术后力学环境稳定,股骨外髁的最大应力分布明显下降,应力、应变明显降低,应力分布均匀。在加载过程中,髌股关节未发生半脱位现象,髌骨运行轨迹更为平稳,减少了髌股关节的磨损。第二部分:股骨滑车发育不良致髌股关节炎的临床研究。本研究对2015年度,因膝关节慢性疼痛于本院就诊并行mri检查的病例进行统计,测量患者的股骨滑车沟角度(≥155.8°);内外侧滑车关节面比例(≤2/5):滑车沟深度(≤4mm);偏颇角(外侧面倾斜度)(≤11°);胫股关节上方3cm、滑车前方的骨性突起。对患病人群的构成比、发病年龄、结构分型、及影像指标进行分析。结果表明,2015年度本机构股骨滑车发育不良的发病率(36.31%),明显高于国外报导的发病率(16.5%)。从中选出300例髌股关节炎病例,参照国内、外文献,我们选定5项mri诊断指标,并对所选取样本进行测量和分型,总结各型所占比例。结果表明,所选定的诊断指标可以很好的用于股骨滑车发育不良的影像学诊断、分型。通过有限元模型的虚拟手术,我们发现手术后髌股关节在不同角度屈伸运动中髌股关节力学环境较为平稳,应力分布较为均匀。以此为理论基础,根据骨骺闭合时间、关节软骨损伤程度和关节炎轻重程度,我们结合滑车发育不良的分型提出几种手术设想:采取软骨下骨及骨骺板近端滑车成型术及骺板近端截骨术,加深滑车后;打磨、修除滑车沟前方乳头样突起;同时采取韧带重建术,使髌股关节的股骨滑车应力分布更为均匀,期待骨骺在正常应力作用下促进骨生长。矫正股骨滑车沟的几何形态,改变骨性结构的力学稳定性,同时修复相关韧带,使股骨滑车力学分布更为均匀。其最终的结果是使患者避免关节置换或推迟初始膝关节置换时间。结论:1.股骨滑车发育不良可导致髌股关节的生物力学稳定性发生改变,诱发髌骨及股骨关节软骨和软骨下骨的急性损伤或慢性劳损,导致关节软骨发生病理改变,从而引发髌股关节炎。2.临床资料表明,本组股骨滑车发育不良的发病率高于文献报导。3.有限元方法证实,韧带重建手术可以改善ftd的膝关节的力学环境,明显降低应力集中现象。4.我们的测量指标结果与经典值一致,可很好地用于股骨滑车发育不良的影像学诊断、分型。更多还原

【Abstract】 Femoral trochlear dysplasia is the abnormal anatomy of the geometrical morphology and depth at femoral trochlear groove.Femoral trochlea is a critical part of the patellofemoral arthrosis.Patellofemoral anatomy anomalies can affect the stability of the knee,induced acute injury or chronic strain of patella and femoral articular cartilage and subchondral bone that will cause pathological changes of the articular cartilage,even the patellofemoral arthritis.With the high morbidity,patellofemoral arthritis is a common disease with knee pain and dysfunction in clinics.As the population aging,the risk of patellofemoral arthritis is rising gradually,while the prevention and treatment of patellofemoral arthritis will be a long process with higher social and economic burden.Therefore,how to solve the occurrence of patellofemoral arthritis fundamentally is the hot topic and should be studied at present.The purpose of this study was to consider the femoral trochlear dysplasia as an independent factor that causes patellofemoral arthritis.On the basis of the three-dimensional finite element model,we explained the biomechanical basis and pathogenesis of femoral trochlear dysplasia.According to the conclusion,we simulated and explored the surgery of treating patellofemoral arthritis mechanically.Finally,we explored the morbidity of patellofemoral arthritis caused by trochlear dysplasia,classification and some therapeutic methods by analyzing the present clinical data.Section 1,The biomechanical basis of femoral trochlear dysplasia.In the present study,we established the finite element model of femoral trochlear dysplasia and analyzed the stress situation of joint bone and cartilage when it was loaded.Then,a virtual surgery was carried out to treat the dysplasia on the model.In order to find the biomechanical basis,we compared the stress and stain around the knee joint pre-or postoperatively.After the MRI and CT scanning,a finite element model of a knee with femoral trochlear dysplasia was established in the MIMICS software.This three-dimensional model was optimized and decorated by Geomagic Studio software.The model was loaded after material properties were given to each part.The stress and strain around the knee,including femoral and tibia bone or cartilage,were tested and analyzed when the joint flexed at 30°,60°,90°and 120°.The procedure was repeated after a virtual surgery-medial patellofemoral ligament reconstruction.As a result,no stress concentration was observed when the knee flexed at 30°.With the gradual flexion,the stress concentration was more obvious at the contact surface between the femoral condyle and patella which is a high risk of patellofeomoral arthritis.After the virtual surgery,the maximum stress contribution decreased obviously at the femoral lateral condyle in a stable mechanical environment,while the no dislocation of patella existed in loading.Section 2,The clinical research of patellofemoral arthritis was caused by the femoral trochlear dysplasia.The patients with knee chronic pain were subjected to MRI scanning were analyzed from January 1st to December 30 th in 2015.The angle of femoral groove,ratio of medial to lateral surface,depth of groove,lateral incline angle or bony prominent above tibial-femoral joint were tested in the present study.We analyzed the constituent ration,incidence age,classification and radiology according to these data.The incidence of femoral trochlear dysplasia is 36.31%,which is significantly higher than the incidence reported abroad(16.5%).Three hundred cases with femoral trochlear dysplasia were analyzed.According to the references,five parameters in MRI were analyzed for the diagnosis or categories of this knee disorder.By analyzing the three dimensional finite element model and the effect of virtual surgery,we found that the stable mechanics environment and the uniform stress distribution were shown around the knee.Therefore,we hypothesized several kinds of surgery may reduce the patients suffering from the knee disorder according to the results of the present virtual surgery,epiphyseal closure,cartilage injury and arthritis severity,such as osteotomy,elimination of the prominent,ligament reconstruction and so on.The uniform mechanical distribution may be shown after the correction of trochlear geography,bone structure or the repair of ligament.Conclusions: a,the change of biomechanical stability in patellofemoral joint,caused by femoral trochlear dysplasia,could induce acute or chronic injury of cartilage or subchondral bone in patella or femur.This pathological change of joint subchondral bone often leads to severe patellofemoral arthritis.b,the mortality of femoral trochlear dysplasia in the present study was significantly higher than that reported in references.c,the finite element analysis showed an significant improvement of mechanical environment and unobvious stress concentration in the knee with FTD after ligament reconstruction.d,in accordance with the classical measurement,the parameters chosen in the present study showed an advantage in the diagnosis and classification of femoral trochlear dysplasia.更多还原