The restraining function of the cruciate ligaments on hyperextension and hyperflexion of the human knee joint

Each of the cruciate ligaments contains functionally different fiber groups; one fiber bundle is always taut; numerous others are taut in intermediate or extreme positions. The bulk of the fibers of the anterior cruciate ligament (ACL) is taut in maximal extension, while that of the posterior cruciate ligament (PCL) is taut in the intermediate positions and in maximal flexion. Fibers taut in extreme positions serve as restraints: during hyperextension, the ACL restrains forward migration of its tibial attachment, while the PCL interacts with other structures to prevent posterior opening of the joint. The inverse situation occurs in hyperflexion. Cruciate fibers are dissimilar in length and angular arrangement so that, when movements are restrained, they lengthen to different extents. To define this phenomenon in quantitative terms, the term isokolyons was coined for lines from which fibers showing identical elongation in percentage on exposure to a force take their origin.     

Structure and vascularization of the cruciate ligaments of the human knee joint

The structure and vascularization of the human anterior and posterior cruciate ligament were investigated by light microscopy, transmission electron microscopy, injection techniques and by immunohistochemistry. The major part of the anterior and posterior cruciate ligament is composed of bundles of type I collagen. Type III collagen-positive fibrils separate the bundles. The major cell type is the elongated fibroblast, lying solitarily between the parallel collagen fibrils. The histologic structure of the cruciate ligaments is not homogeneous. In both ligaments there is a zone where the tissue resembles fibrocartilage. In the anterior cruciate ligament the fibrocartilaginous zone is located 5–10 mm proximal of the tibial ligament insertion in the anterior portion of the ligament. In the posterior cruciate ligament the fibrocartilage is located in the central part of the middle third. Within those zones the cells are arranged in columns and the cell shape is round to ovoid. Transmission electron microscopy reveals typical features of chondrocytes. The chondrocytes are surrounded by a felt-like pericellular matrix, a high content of cellular organelles and short processes on the cell surface. The pericellular collagen is positive for type II collagen. The major blood supply of the cruciate ligaments arises from the middle geniculate artery. The distal part of both cruciate ligaments is vascularized by branches of the lateral and medial inferior geniculate artery. Both ligaments are surrounded by a synovial fold where the terminal branches of the middle and inferior arteries form a periligamentous network. From the synovial sheath blood vessels penetrate the ligament in a horizontal direction and anastomose with a longitudinally orientated intraligamentous vascular network. The density of blood vessels within the ligaments is not homogeneous. In the anterior cruciate ligament an avascular zone is located within the fibrocartilage of the anterior part where the ligament faces the anterior rim of the intercondylar fossa. The fibrocartilaginous zone of the middle third of the posterior cruciate ligament is also avascular. According to Pauwel’s theory of the ”causal histogenesis” (1960) the stimulus for the development of fibrocartilage within dense connective tissue is shearing and compressive stress. In the anterior cruciate ligament this biomechanical situation may occur when the ligament impinges on the anterior rim of the intercondylar fossa when the knee is fully extended. Compressive and shearing stress in the center of the middle third of the posterior cruciate ligament may result from twisting of the fiber bundles. Accepted: 12 March 1999     

Experimental evaluation of 3-dimensional kinematic behavior of the cruciate ligaments

PURPOSE: The purpose of this study was to evaluate a low-cost and easily reproducible technique for biomechanical studies in cadavers. In this kind of study, the natural effect of loading of the joint and shear forces are not taken into account. The objective is to describe the plastic deformation of the ligaments into 3-dimensional space. METHOD: For 18 intact human cadaver knees, the cruciate ligaments were divided into 3 fiber bundles, the tibial or femoral fixation points were marked, and 2 perpendicular different x-ray exposures were performed, thus obtaining radiographs of spatial projections of the bundle in 3 anatomic planes (frontal, sagittal, and transversal). From the measurements made on the x-ray films, we obtained the average distance between the 2 fixation points of the cruciate ligaments on the tibia and the femur at 4 different flexion angles. RESULTS: The distance between the fixation points of the medial and lateral fiber bundles of the cruciate ligaments did not change significantly during movement. There were, however, significant variations (P < .05) in the distance between the fixation points of the posterior fiber bundles of the anterior cruciate ligament and the anterior fiber bundles of the posterior cruciate ligament. CONCLUSIONS: This technique was efficient for demonstrating the plastic deformability of the cruciate ligaments. The results proceeding from this type of study can assist in the planning of physical rehabilitation programs.     

The change in length of the medial and lateral collateral ligaments during in vivo knee flexion

The collateral ligaments of the knee are important in maintaining knee stability. However, little data has been reported on the in vivo function of the collateral ligaments. The objective of this study was to investigate the change in length of different fiber bundles of the medial collateral ligament (MCL), deep fibers of the MCL (DMCL) and the lateral collateral ligament (LCL) during in vivo knee flexion. The knees of five healthy subjects were scanned using magnetic resonance imaging. These images were used to create three-dimensional models of the tibia and femur, including the insertions of the collateral ligaments. The MCL, DMCL, and LCL were each divided into three equal portions: an anterior bundle, a middle bundle and a posterior bundle. Next, the subjects were imaged from two orthogonal directions using fluoroscopy while performing a quasi-static lunge for 0 degree to 90 degrees of flexion. The models and fluoroscopic images were then used to reproduce the in vivo motion of the knee. From these models, the length of each bundle of each ligament was measured as a function of flexion. The length of the anterior bundle of the MCL did not change significantly with flexion. The length of the posterior bundle of the MCL consistently decreased with flexion (p less than 0.05). The changes in deformation of the DMCL and LCL as a function of flexion were similar to each other. The length of the anterior bundles increased with flexion and the length of the posterior bundles decreased with flexion. These data indicate that the collateral ligaments do not elongate uniformly as the knee is flexed, with different bundles becoming taut and slack. These data may help to provide a better understanding of the in vivo function of the collateral ligaments and be used to improve surgical reconstruction of the collateral ligaments. Furthermore, the data suggest that the different roles of various portions of the collateral ligaments along the flexion path should be considered before releasing the collateral ligaments during knee arthroplasty.     

Erratum to "The change in length of the medial and lateral collateral ligaments during in vivo knee flexion"

The collateral ligaments of the knee are important in maintaining knee stability. However, little data has been reported on the in vivo function of the collateral ligaments. The objective of this study was to investigate the change in length of different fiber bundles of the medial collateral ligament (MCL), deep fibers of the MCL (DMCL) and the lateral collateral ligament (LCL) during in vivo knee flexion. The knees of five healthy subjects were scanned using magnetic resonance imaging. These images were used to create three-dimensional models of the tibia and femur, including the insertions of the collateral ligaments. The MCL, DMCL, and LCL were each divided into three equal portions: an anterior bundle, a middle bundle and a posterior bundle. Next, the subjects were imaged from two orthogonal directions using fluoroscopy while performing a quasi-static lunge from 0 degrees to 90 degrees of flexion. The models and fluoroscopic images were then used to reproduce the in vivo motion of the knee. From these models, the length of each bundle of each ligament was measured as a function of flexion. The length of the anterior bundle of the MCL did not change significantly with flexion. The length of the posterior bundle of the MCL consistently decreased with flexion (p < 0.05). The change in length of the DMCL with flexion was similar to the trend observed for the MCL. The length of the anterior bundle of the LCL increased with flexion and the length of the posterior bundle decreased with flexion. These data indicate that the collateral ligaments do not elongate uniformly as the knee is flexed, with different bundles becoming taut and slack. These data may help to provide a better understanding of the in vivo function of the collateral ligaments and be used to improve surgical reconstructions of the collateral ligaments. Furthermore, the data suggest that the different roles of various portions of the collateral ligaments along the flexion path should be considered before releasing the collateral ligaments during knee arthroplasty.     

MRI探究交叉韧带松紧度与髌股关节面损伤相关性的临床应用

目的　探究交叉韧带松紧度与髌股关节面损伤程度的相关性,分析个体交叉韧带长度的解剖差异对髌股关节面损伤的影响,为预防和诊治髌股关节面疾病提供新的依据。 方法　随机收集南方医科大学珠江医院2016年10月至2017年12月110例膝关节MRI资料,磁共振矢状位上测量前、后交叉韧带长度A与B,测量前、后交叉韧带起止点距离La与Lb,计算交叉韧带松紧度M值;根据矢状位与冠状位上评判髌股关节面损伤程度0、I、II、III与IV级并分别设5个组。通过SPSS20.0统计学软件,将所得数据进行One-Way ANOVA方差分析与Spearman相关性分析,探究交叉韧带松紧度与髌股关节面损伤程度的相关性。 结果　One-Way ANOVA方差分析得出各组M值两两之间均存在显著性差异（P<0.05）,Spearman相关性分析显示M值与髌股关节损伤程度间存在正相关性。 结论　交叉韧带松紧度与髌股关节面损伤存在相关性,随着M值越大,髌股关节面损伤程度越严重。     

人工韧带修复膝关节交叉韧带损伤

背景：以往治疗膝关节交叉韧带损伤的主要手段是移植重建,最常用的移植材料为自体的骨髌腱骨、半腱肌腱和股薄肌腱。但由于此类移植物存在取材区并发症及韧带化过程中的各种问题,近年来人工韧带的研究受到重视。 目的：认识膝关节交叉韧带的结构及血供特点,以及膝关节交叉韧带损伤后人工韧带重建治疗机制与临床应用特点。 方法：①分析膝关节前、后交叉韧带的组织结构,功能学特点以及血供差异。②分析膝关节前、后交叉韧带损伤的类型及生物力学机制。③分析修复膝关节交叉韧带损伤的材料学分类及特点。④分析人工韧带修复后影响关节稳定性的因素。 结果与结论：修复膝关节前、后交叉韧带损伤时,应首先考虑到前、后交叉韧带的功能及血供情况,选择合适的重建物,使重建时过程简化,操作简单,重建材料的组织相容性较好,达到修复后的解剖与功能的双重建。     

喙肱韧带的应用解剖

目的:探讨喙肱韧带(coracohumeral ligament,CHL)的解剖学特点。方法:观察20侧正常成人肩关节标本的CHL位置、形态、起止点及与盂肱上韧带的关系;CHL在肩关节各种活动中所处的状态;CHL与关节囊融合处、CHL根部组织、关节囊及喙肩韧带组织学特点。结果:20侧CHL全部起于喙突基底部的外侧缘;9侧止于冈上肌腱,7侧止于肩袖间隙,3侧止于冈上肌腱和肩胛下肌腱,1侧止于肩胛下肌腱;其中11侧可见CHL与盂肱上韧带存在纤维组织连接;CHL于肩关节旋外、前屈、后伸、内收、肱骨头前后平动时紧张,于旋内、中立位、外展位时松弛;CHL与关节囊融合处、CHL根部组织与关节囊组织学特点相似,均呈现关节囊组织的典型特点,喙肩韧带呈现出韧带的特有表现。结论:CHL位置与形态相对固定,起点一致,但止点呈多样性;CHL与盂肱上韧带复合体不固定;CHL在不同运动状态其紧张度不一;CHL与关节囊组织形态相似,是关节囊增厚部。     

半月板和交叉韧带矢状断层研究

目的　观察膝关节矢状断层的半月板和交叉韧带的形态、可出现的层面情况并测量有关数据 ,为影像学诊断提供解剖学依据。方法　 11例 (2 2侧 )经福尔马林液防腐的膝关节标本按MRI检查姿势标线 ,冷冻后用断层带锯作厚 5mm的矢状断层 ,获得 314断层 (观察 5 84层面 ) ,对各断层面的半月板和交叉韧带进行观察 ,并用电子游标卡尺进行测量。结果　半月板后角高度明显高于前角 (P <0 0 1) ,内侧半月板后角宽度约是前角的 2倍 ,而外侧半月板宽度前、后角基本一致 ,外侧半月板体部宽于内侧且更靠近中轴 ,盘状半月板主要发生于外侧 ;正中矢状面显示交叉韧带全长的出现率为 82 % ,其全长的最好层面为正中矢状面和正中旁 1cm层面 ;前交叉韧带与矢状面的夹角较后交叉韧带小 ;前、后交叉韧带在股骨和胫骨的附着点宽约 12mm ,各附着点宽差异无显著性 (P >0 0 5 )。结论　膝关节矢状断层形态学研究提示半月板的后角容易损伤 ;外侧半月板后角明显较内侧窄而高 ,此为临床所见外侧半月板较内侧半月板更易损伤的形态学基础。     

Functional Activity of the Anterior and Posterior Cruciate Ligaments Under In Vivo Gait and Static Physiological Loads

The loading of the anterior and posterior cruciate ligaments (ACL and PCL) during normal gait has not been quantified. Also, it is not clear whether ligaments under “static” physiological loads commonly used in cadaveric studies behave similarly to normal gait experienced in vivo. We measured the in vivo kinematics of the stifle joint of sheep (N = 4) during “normal gait,” then reproduced these gait paths using a robotic system. The loads borne by the cruciate ligaments were determined using the principle of superposition and plotted against each other. This indicated some functional interaction between the ACL and PCL under in vivo physiological loads. To examine this relationship under static loading conditions, cadaveric knees (N = 6) were tested in the anterior–posterior (AP) direction, along the axes of the ACL and the PCL, as well as under combined AP and tibial rotations. The same process was repeated after either the ACL (N = 3) or the PCL (N = 3) was transected. Our results show a mutually exclusive relationship in ACL and PCL load bearing under both “in vivo gait” and “static” loading conditions. High ACL loads were associated with low PCL loads and vice versa. This is a novel study quantifying the actions of the cruciate ligaments during gait and comparing them to commonly used static loading conditions in cadaveric studies.     

膝关节后纵隔与后交叉韧带下止点的解剖关系及临床意义

目的 探讨膝关节后纵隔与后交叉韧带(PCL)下止点的解剖关系及其在PCL重建中的临床价值. 方法 解剖22例新鲜冷冻膝关节,将PCL在屈膝90°下按纤维张力的不同分为前外束和后内束,解剖出它们在胫骨上的足迹,并用墨汁标记足迹的轮廓;使用带标尺的数码相机测量PCL前外束、后内束胫骨止点中心点与后纵隔的水平距离,并同时测量两束止点中心点与外侧胫骨平台后软骨缘上表面的垂直距离. 结果 膝关节存在一个从前至后的纵隔结构,其前方与脂肪垫、翼状皱襞或黏膜韧带相连,中间位于前、后交叉韧带之间,后方形成膝关节的后纵隔.在22个膝关节中,8个膝关节的后纵隔从PCL的外缘绕过以后止于后关节囊,占36.36%;14个膝关节的后纵隔在PCL前方分叉,包绕PCL后止于后关节囊,占63.64%.PCL前外束胫骨止点中心点距离后纵隔内侧的水平距离(0.90±2.40)mm,距离外侧胫骨平台后软骨缘上表面的垂直距离是(3.25±1.20)mm.后内束胫骨止点中心点距离后纵隔内侧的水平距离为(4.35±2.46)mm,距离外侧胫骨平台后软骨缘上表面的垂直距离为(6.91±1.57)mm. 结论 膝关节后纵隔与PCL下止点的解剖关系密切,后纵隔可以成为PCL单束重建和双束重建手术中胫骨止点定位的重要解剖标志之一.     

膝关节交叉韧带和侧副韧带的断面解剖学研究及其意义

目的研究膝关节交叉韧带和侧副韧带的断面形态特征和变化规律,为诊断膝部韧带病变提供更为详尽的形态学资料。方法利用27例正常成人膝关节标本制作连续断面,其中矢状断面9例,冠状断面12例,横断面6例。通过横、矢、冠状断面标本,观测膝关节韧带的断面形态特征及定量测量。结果矢状面上测量前、后交叉韧带长度分别为(29.66±4.21)mm、(40.26±6.81)mm,厚度分别为(10.03±1.97)mm、(11.24±3.50)mm。冠状面上前、后交叉韧带长径分别为(15.18±3.25)mm、(18.79±3.35)mm,短径分别为(6.37±1.32)mm、(8.03±1.46)mm;胫、腓侧副韧带长度分别为(102.85±19.64)mm、(45.52±14.91)mm,厚度分别为(2.63±0.72)mm、(3.43±1.04)mm。髁间隆起的横断面上胫、腓侧副韧带长径分别为(21.98±11.95)mm、(5.25±1.93)mm,短径分别为(2.03±0.59)mm、(2.87±0.64)mm。结论 (1)观测交叉韧带最好的断面是膝关节正中矢状面,其次是正中旁开1个矢状断面。除厚度外,在矢状面上前后交叉韧带长度、股、胫骨附着区宽度均有明显差异。(2)胫、腓侧副韧带在连续的冠状断面及横断面上均可显示,以冠状断面配合横断面相对为佳。     

The menisco-femoral ligaments

The menisco-femoral ligaments were studied in 60 knees from 30 dissecting room cadavers. The anterior horns of the menisci were attached to the intercondylar area of the femur by discrete antero-medial or antero-lateral menisco-femoral ligaments, separate from the anterior cruciate ligament, in 15% of knees for each meniscus, more frequently than previously appreciated; these anterior horn ligaments may exacerbate a meniscal tear. The posterior horn of the lateral meniscus was connected with the intercondylar area of the femur in 100% of knees. In 93% of knees a ligament ran behind the posterior cruciate ligament while in 33% of knees a ligament ran in front of the posterior eruciate ligament. We propose renaming these the pre-cruciate postero-lateral menisco-femoral ligament and post-cruciate postero-lateral menisco-femoral ligament, respectively, to avoid confusion with the ligaments of the anterior horns. The menisco-femoral ligaments may function in controlling movement of the menisci, especially during rotation of the knee. The posterior horn of the medial meniscus has no direct femoral attachment and this may be a factor in the increased risk of injury to this meniscus. © 1995 WiIey-Liss, Inc.     

Intraarticular ganglion cyst around the cruciate ligament of the knee

Intraarticular ganglion cysts arising from the cruciate ligaments are encountered infrequently. We report two cases in which intraarticular ganglion cysts arising from the anterior cruciate ligament and the posterior cruciate ligament, respectively. In both cases, dull pain in the full flexion position was observed and magnetic resonance imaging was helpful for the preoperative diagnosis.     

足韧带的解剖学研究及其临床意义

目的:研究足韧带的解剖学特点,探讨其临床意义。方法:30侧成人足标本解剖观测各韧带起至、走行和比邻,分析其作用。结果:距舟背侧韧带分为内、外两束。楔舟背侧韧带分为内、中、外、斜4束。足横弓和纵弓交汇处为足底最凹点,足底长短韧带、腓骨长肌腱、胫骨后肌腱为"外三角",楔舟足底韧带、楔骰足底韧带、跟舟足底韧带为"内三角",维系该凹点。跟舟足底韧带承托距骨头部,是将踝压力分向第1跖骨头和足跟的首要韧带。各楔骨、楔骰骨间韧矢状面上都位于关节前侧,不规则形,质地强韧,维系足横弓。结论:足部韧带分为足背、足底和骨间3个系统,结构复杂,其功能及其在创伤外科中的意义有待深入研究。     

基于MRI对交叉韧带松紧度与半月板损伤的相关性研究

目的　探究交叉韧带的松紧度与半月板损伤的相关性,从解剖学上探索半月板损伤的影响因素,为预测和诊断半月板损伤提供新的依据。 方法　收集南方医科大学珠江医院2014年1月~2016年12月260例患者单膝关节伸直位的MRI资料。在各膝MRI相同矢状面分别测量前、后交叉韧带的长度a和p,及其起止点的距离la和lp。计算出交叉韧带松紧度系数R=(a+p)/(la+lp)。用t检验比较各组患者间的差异性,用Spearman 相关分析分别探讨松紧度系数与半月板损伤的相关性。 结果　 t检验：无论是否存在骨关节炎,半月板损伤组和无半月板损伤组的R值均存在显著差异性（P <0.05）。Spearman相关性分析：无骨关节炎患者中rs=0.620,R值与半月板损伤存在较强的正相关性;有骨关节炎患者中rs =0.313,R值与半月板损伤存在弱正相关性。 结论　交叉韧带松紧度与半月板损伤存在一定程度的相关性,特别在膝关节无骨关节炎的年轻患者中,韧带越松弛,半月板损伤越容易发生。但在膝关节有关节炎的老年患者中,交叉韧带的松紧程度并非半月板损伤的主要因素。     

Morphological variations of the deltoid ligament of the medial ankle

Morphological variations of the deltoid ligament were investigated in this study, with the aim of classifying the different types on the basis of their components. Sixty ankles from 39 cadavers were dissected. The origin and insertion sites of the deltoid ligament were identified, and its length, width, and thickness were measured. The deltoid ligament was divided into two layers, superficial and deep, which respectively comprised four components (tibionavicular, tibiospring, tibiocalcaneal, and superficial posterior tibiotalar ligaments) and two components (anterior tibiotalar and deep posterior tibiotalar ligaments). The tibiospring and tibiocalcaneal ligaments were found in 100% of the specimens, while the prevalence rates of other components lay within the range 63.3–96.7%. The tibionavicular and deep posterior tibiotalar ligaments were the thinnest and thickest, respectively, while the other ligaments had similar thicknesses. The deltoid ligament was classified into types I–IV according to the combinations of these components: all components were present in type I (48.3%), the tibionavicular ligament was absent in type II (36.7%), only the superficial posterior tibiotalar ligament was absent in type III (6.7%), and only the anterior tibiotalar ligament was absent in type IV (8.3%). In conclusion, these results improve knowledge of the morphological and morphometric characteristics of the deltoid ligament and thus provide helpful information for surgical procedures in this region. Clin. Anat. 29:1059–1065, 2016. © 2016 Wiley Periodicals, Inc.     

前交叉韧带重建股骨足迹精确定位的解剖与临床研究

目的　探讨前交叉韧带（ACL）个性化解剖重建术中韧带止点足迹精确定位的方法及效果。 方法　①15侧膝关节尸体标本,标记ACL股骨足迹,观察ACL足迹长轴与股骨干角度、前内束（AM）中心位点距后软骨缘距离、后外束（PL）中心位点距下软骨缘距离。②15例行ACL重建患者,术中采用三入路观察与导航定位方法明确ACL股骨足迹,测量AM与PL连线与股骨干夹角、AM距后软骨缘距离、PL距下软骨缘距离。 结果　15例膝关节尸体标本ACL股骨足迹长轴与股骨干角度为（18.5±　2.5）°、AM与股骨外髁内面后缘距离为（6.1±1.8）mm、PL距离下软骨缘距离为（6.2±2.2）mm,但每个标本均不相同。导航显示,ACL股骨足迹长轴与股骨干夹角为（19.3±3.1）°,AM与股骨外髁内面后缘为（5.8±1.2）mm、PL距离下软骨缘为（5.9±2.5）mm,各数据相差较大。 结论　①ACL股骨与胫骨解剖足迹变异较大,应根据每例ACL足迹不同进行精确的个性化解剖重建。②以同一个标准进行所有ACL重建难以达到真正的解剖重建。