III度膝关节内侧副韧带损伤缝合锚重建术后异位骨化8例临床分析

目的:分析8例III度膝关节内侧副韧带损伤的患者行缝合锚重建术后异位骨化发生与损伤的关系。方法:回顾性收集8例Ⅲ度膝关节内侧副韧带损伤行缝合锚重建术后发生异位骨化的患者,对其临床一般资料、损伤程度及部位、膝关节活动度及异位骨化程度等进行分析。结果:8位中Ⅰ度异位骨化4例,膝关节活动度73.75°~176.25°,平均125°,Ⅱ°异位骨化4例,膝关节活动度78.75°~157.25°,平均117.4°。在发生内侧副韧带异位骨化的8名患者中,仅有1名为单纯内侧副韧带损伤导致,其余7名患者中5名合并前叉或前、后叉韧带损伤,1例伴有胫骨髁间棘的撕脱骨折,1例合并胫骨平台骨折,4例合并胫骨或股骨髁骨折。结论:膝关节内侧异位骨化是异位骨化的好发部位,其发生与膝关节多发韧带损伤有关。     

New parameters describing how knee ligaments carry force in situ predict interspecimen variations in laxity during simulated clinical exams

Knee laxity, defined as the net translation or rotation of the tibia relative to the femur in a given direction in response to an applied load, is highly variable from person to person. High levels of knee laxity as assessed during routine clinical exams are associated with first-time ligament injury and graft reinjury following reconstruction. During laxity exams, ligaments carry force to resist the applied load; however, relationships between intersubject variations in knee laxity and variations in how ligaments carry force as the knee moves through its passive envelope of motion, which we refer to as ligament engagement, are not well established. Thus, the objectives of this study were, first, to define parameters describing ligament engagement and, then, to link variations in ligament engagement and variations in laxity across a group of knees. We used a robotic manipulator in a cadaveric knee model (n = 20) to quantify how important knee stabilizers, namely the anterior and posterior cruciate ligaments (ACL and PCL, respectively), as well as the medial collateral ligament (MCL) engage during respective tests of anterior, posterior, and valgus laxity. Ligament engagement was quantified using three parameters: (1) in situ slack, defined as the relative tibiofemoral motion from the neutral position of the joint to the position where the ligament began to carry force; (2) in situ stiffness, defined as the slope of the linear portion of the ligament force–tibial motion response; and (3) ligament force at the peak applied load. Knee laxity was related to parameters of ligament engagement using univariate and multivariate regression models. Variations in the in situ slack of the ACL and PCL predicted anterior and posterior laxity, while variations in both in situ slack and in situ stiffness of the MCL predicted valgus laxity. Parameters of ligament engagement may be useful to further characterize the in situ biomechanical function of ligaments and ligament grafts.     

Effects of medial collateral ligament release,limb correction,and soft tissue laxity on knee joint contact force distribution after medial opening wedge high tibial osteotomy: a computational study

In this study, the effects of medial collateral ligament (MCL) release and the limb correction strategies with pre-existing MCL laxity on tibiofemoral contact force distribution after high tibial osteotomy (HTO) were investigated. The medial and lateral contact forces of the knee were quantified during simulated standing using computational modeling techniques. MCL slackness had a primary influence on contact force distribution of the knee, while there was little effect of simulated limb correction. Anterior and middle bundle release, which involved the partial release of two-thirds of the superficial MCL, was shown to be an optimal surgical method in HTO, achieving balanced contact distribution in simulated weight-bearing standing.     

Role of knee ligaments in proprioception and regulation of muscle stiffness

Physiologic evidence for the sensory role of the knee joint ligaments are reviewed. The cruciate and collateral ligaments accomodate morphologically different sensory nerve endings with different capabilities of providing the central nervous system (CNS) with information not only about noxious and chemical stimuli but also about mechanical events, e.g., movement- and position-related stretches of the ligaments. Available data show that low-threshold joint/ligament receptor (i.e., mechanoreceptor) afferents evoke only weak and rare effects in skeletomotor neurons (α-motoneurons), whereas they frequently and powerfully influence fusimotor neurons (γ-motoneurons). The effects on the γ-muscle-spindle system in the muscles around the knee are so potent that even stretches of the cruciate ligaments at relatively moderate loads (not noxious) may induce major changes in responses of the muscle spindle afferents. As the activity in the primary muscle spindle afferents modifies stiffness in the muscles, the cruciate ligament receptors may, through the γ-muscle-spindle system, participate in regulation and preparatory adjustment of the stiffness of the muscles around the knee joint and thereby of knee joint stiffness. Thus, the sensory system of the cruciate ligaments is able to contribute significantly to the functional stability of the knee joint. The possible role of (ligamentous) joint receptors in genesis and spread of muscular tension in occupational muscle pain and in chronic musculoskeletal pain syndromes is also discussed.     

Geometrical changes of knee ligaments and patellar tendon during passive flexion

Patterns of fibre elongation and orientation for the cruciate and collateral ligaments of the human knee joint and for the patellar tendon have not yet been established in three-dimensions. These patterns are essential for understanding thoroughly the contribution of these soft tissues to joint function and of value in surgical treatments for a more conscious assessment of the knee status. Measurements from 10 normal cadaver knees are here reported using an accurate surgical navigation system and consistent anatomical references, over a large flexion arc, and according to current recommended conventions. The contours of relevant sub-bundles were digitised over the corresponding origins and insertions on the bones. Representative fibres were calculated as the straight line segments joining the centroids of these attachment areas. The most isometric fibre was also taken as that whose attachment points were at the minimum change in length over the flexion arc. Changes in length and orientation of these fibres were reported versus the flexion angle. A good general repeatability of intra- and inter-specimens was found. Isometric fibres were found in the locations reported in the literature. During knee flexion, ligament sub-bundles slacken in the anterior cruciate ligament, and in the medial and lateral collateral ligaments, whereas they tighten in the posterior cruciate ligament. In each cruciate ligament the two compounding sub-bundles have different extents for the change in fibre length, and also bend differently from each other on both tibial planes. In the collateral ligaments and patellar tendon all fibres bend posteriorly. Patellar tendon underwent complex changes in length and orientation, on both the tibial sagittal and frontal planes. For the first time thorough and consistent patterns of geometrical changes are provided for the main knee ligaments and tendons after careful fibre mapping.     

Contribution of biomechanics to management of ligament and tendon injuries

The contribution of biomechanics to the advancement of management of ligament and tendon injuries has been significant. Thanks to Professor Y.C. Fung's writing and guidance, our field of research has done fundamental work on anatomy and biology of ligaments and tendons, developed methods to accurately determine mechanical properties, identified various experimental factors which could change the outcome measurements as well as examined biological factors that change tissue properties in-vivo. Professor Fung also gave us his quasi-linear viscoelastic theory for soft tissues so that the time and history dependent properties of ligaments and tendons could be properly described. We have further adopted Professor Fung's eight steps on methods of approach for biomechanical investigation to understand as well as enhance the treatment of ligament and tendon injuries during work or sports related activities. Examples on how to better treat the tears of the medial collateral ligament of the knee, as well as how to improve reconstruction procedures for the anterior cruciate ligament are presented in detail. Currently the use of functional tissue engineering for ligament and tendon healing is a topic of great interest. Here the use of biological scaffolds, such as porcine small intestinal submucosa, has shown promise. For the last 35 to 40 years, the field of biomechanics has made great strides in the treatment of ligament and tendon injuries, and many patients have benefited. The future is even brighter because of what has been done properly in the past. Exciting advances can be made in the field of tissue engineering through novel in-vitro culture and bioscaffold fabrication techniques. Recent technology can also allow the collection of in-vivo data so that ligament and tendon injuries can be better understood. Yet, solving new and more complex problems must still follow the stepwise methods of approach as taught by Professor Fung.     

Effect of ACL deficiency on MCL strains and joint kinematics

The knee joint is partially stabilized by the interaction of multiple ligament structures. This study tested the interdependent functions of the anterior cruciate ligament (ACL) and the medial collateral ligament (MCL) by evaluating the effects of ACL deficiency on local MCL strain while simultaneously measuring joint kinematics under specific loading scenarios. A structural testing machine applied anterior translation and valgus rotation (limits 100 N and 10 N m, respectively) to the tibia of ten human cadaveric knees with the ACL intact or severed. A three-dimensional motion analysis system measured joint kinematics and MCL tissue strain in 18 regions of the superficial MCL. ACL deficiency significantly increased MCL strains by 1.8% (p<0.05) during anterior translation, bringing ligament fibers to strain levels characteristic of microtrauma. In contrast, ACL transection had no effect on MCL strains during valgus rotation (increase of only 0.1%). Therefore, isolated valgus rotation in the ACL-deficient knee was nondetrimental to the MCL. The ACL was also found to promote internal tibial rotation during anterior translation, which in turn decreased strains near the femoral insertion of the MCL. These data advance the basic structure-function understanding of the MCL, and may benefit the treatment of ACL injuries by improving the knowledge of ACL function and clarifying motions that are potentially harmful to secondary stabilizers.     

Measuring ligament elasticity of the knee joint--elasticity measuring strip and its alternatives]

Those techniques for measuring ligament tension at the knee joint that are most commonly cited and easiest to carry out are discussed. These include four techniques based on the use of strain gauges. Apart from the Omega transducer and the buckle transducer, there is also the tendon force transducer, and the application of strain gauges to the bony ligament insertion sites. Other indirect measuring methods considered are the mercury strain transducer and the Hall effect transducer. The parameter measured with all of these methods is fluctuating current or voltage, which is then correlated with ligament tension. Three direct measurements are also discussed: the separation distances of marked fibres of the ligaments, replacement of fibres by threads, and a load cell/bone plug construction. The measured value is equated with the effective change in ligament length.     

Revisiting the role of hyperbaric oxygen therapy in knee injuries: Potential benefits and mechanisms

Knee injury negatively impacts routine activities and quality of life of millions of people every year. Disruption of tendons, ligaments, and articular cartilage are major causes of knee lesions, leading to social and economic losses. Besides the attempts for an optimal recovery of knee function after surgery, the joint healing process is not always adequate given the nature of intra-articular environment. Based on that, different therapeutic methods attempt to improve healing capacity. Hyperbaric oxygen therapy (HBOT) is an innovative biophysical approach that can be used as an adjuvant treatment post-knee surgery, to potentially prevent chronic disorders that commonly follows knee injuries. Given the well-recognized role of HBOT in improving wound healing, further research is necessary to clarify the benefits of HBOT in damaged musculoskeletal tissues, especially knee disorders. Here, we review important mechanisms of action for HBOT-induced healing including the induction of angiogenesis, modulation of inflammation and extracellular matrix components, and activation of parenchyma cells—key events to restore knee function after injury. This review discusses the basic science of the healing process in knee injuries, the role of oxygen during cicatrization, and shed light on the promising actions of HBOT in treating knee disorders, such as tendon, ligament, and cartilage injuries.     

腓骨短肌腱外侧韧带重建术治疗慢性踝关节外侧不稳的临床疗效

目的:研究外侧副韧带重建手术结合关节镜检查治疗慢性踝关节外侧不稳的临床疗效。方法:选取2012年7月-2014年7月我院收治的慢性踝关节外侧不稳患者60例,随机分为研究组和对照组,每组30例。对照组患者给予保守治疗,研究组患者采取踝关节镜探查清理联合腓骨短肌腱外侧韧带重建手术进行治疗。应用美国足踝外科裸-后足功能评分系统(AOFAS)评价两组患者治疗前后的踝关节功能评分,并比较两组的优良率、复发率以及并发症的发生率。结果:两组治疗前的AOFAS功能评分比较无统计学差异(P0.05),两组治疗后的AOFAS功能评分均较治疗前显著升高,且研究组显著高于对照组,差异具体统计学意义(P0.05)。研究组的优良率为96.7%(29/30),显著高于对照组的73.3%(22/30);研究组的复发率为0.0%(0/30),显著低于对照组的13.3%(4/30);研究组并发症的发生率为3.3%(1/30),显著低于对照组的20.0%(6/30),两组比较差异均具有统计学意义(P0.05)。结论:外侧副韧带重建手术结合关节镜检查治疗慢性踝关节外侧不稳具有较好的临床疗效,且复发率较低,并发症较少。     

Establishment and comparison of fibroblast cell lines from the medial collateral and anterior cruciate ligaments of the rabbit

Summary We have developed a procedure to explant fibroblasts from the anterior cruciate ligament (ACL) and the medial collateral ligament (MCL) of the rabbit knee, and have optimized conditions for maintaining them in culture. Maximal growth for both ACL and MCL cells was obtained with Dulbecco's modified Eagle's medium supplemented with 15% fetal bovine serum and 250 μM ascorbate. ACL and MCL fibroblasts displayed intrinsic differences in their responses to changes in culture parameters. Specifically, they displayed different growth responses when plated at different densities and responded to RPMI 1640 medium in very different ways. There were also biochemical differences between the cell types. Both cell types produced similar amounts of collagen in culture, but the ratio of type I to type III, the major collagen subtypes produced by these cells, were different. ACL fibroblasts produced 86.7% type I and 13.3% type III, and MCL fibroblasts produced 71.1% type I and 28.9% type III. In addition, total protein produced by ACL fibroblasts was higher than that produced by MCL cells. This confirms the suggestions of previous researchers that such differences might exist. This work was funded by a grant-in-aid from Medtronic of Canada, by an R&D Grant from the Alberta Ministry of Technology, Research and Telecommunications, and by the Alberta Heritage Foundation for Medical Research.     

Evaluation of an intact,an ACL-deficient,and a reconstructed human knee joint finite element model

The human knee joint has a three-dimensional geometry with multiple body articulations that produce complex mechanical responses under loads that occur in everyday life and sports activities. Understanding the complex mechanical interactions of these load-bearing structures is of use when the treatment of relevant diseases is evaluated and assisting devices are designed. The anterior cruciate ligament (ACL) in the knee is one of four main ligaments that connects the femur to the tibia and is often torn during sudden twisting motions, resulting in knee instability. The objective of this work is to study the mechanical behavior of the human knee joint and evaluate the differences in its response for three different states, i.e., intact, ACL-deficient, and surgically treated (reconstructed) knee. The finite element models corresponding to these states were developed. For the reconstructed model, a novel repair device was developed and patented by the author in previous work. Static load cases were applied, as have already been presented in a previous work, in order to compare the calculated results produced by the two models the ACL-deficient and the surgically reconstructed knee joint, under the exact same loading conditions. Displacements were calculated in different directions for the load cases studied and were found to be very close to those from previous modeling work and were in good agreement with experimental data presented in literature. The developed finite element model for both the intact and the ACL-deficient human knee joint is a reliable tool to study the kinematics of the human knee, as results of this study show. In addition, the reconstructed human knee joint model had kinematic behavior similar to the intact knee joint, showing that such reconstruction devices can restore human knee stability to an adequate extent.     

Efficient probabilistic representation of tibiofemoral soft tissue constraint

Verified and efficient representations of knee ligamentous constraints are essential to forward-dynamic models for prediction of knee mechanics. The objectives of this study were to develop an efficient probabilistic representation of knee ligamentous constraint using the advanced mean value (AMV) probabilistic approach, and to compare the AMV representation with the gold standard Monte Carlo (MC) approach. Specifically, the effects of inherent uncertainty in ligament stiffness, reference strain and attachment site locations on joint constraint were assessed. An explicit finite element model of the knee was evaluated under a series of anterior–posterior (AP) and internal–external (IE) loading at full extension and 90° flexion. Distributions of AP and IE laxity were predicted using experimentally-based levels of ligament parameter variability. Importance factors identified the critical properties affecting the predicted bounds, and agreed with reported ligament recruitment. The AMV method agreed closely with MC results with a four-fold reduction in computation time.     

The collateral ligaments of the knee joint in the cat and man. Morphological and functional study of the internal arrangement of fibers

The present investigation of fiber arrangement in the collateral ligaments of the knee was carried out in cats and man in various positions of flexion and extension, without compression load. In all knee joint positions, the fibers of the collateral ligaments are twisted except for the fibers in the meniscal part of the medial collateral ligament which have a parallel arrangement. Furthermore, most of the fibers in the collateral ligaments are taut in all positions of the knee joint in both cat and man. By means of planar models representing different fiber arrangements, the kinematic behavior of the collateral ligaments was analyzed. It appears that a crossed (twisted) arrangement of the fibers is most effective in rotatory movements, whereas a parallel orientation is most effective in translation. Our data further indicate that, in measuring the changes in lengths of ligaments during joint motion, one cannot neglect the internal arrangement of fibers and the geometry of the articular surfaces and menisci.     

猪膝关节与人膝关节的对比及其在生物力学测试中的应用

人膝关节结构复杂,韧带较多,其中交叉韧带对维持膝关节的稳定性至为重要.后交叉韧带(posterior cruciate ligament,PCL)对于维持膝关节的后向稳定性和旋转稳定性具有至关重要的作用.PCL损伤后的主观不适症状要明显少于前交叉韧带损伤,所以过去对PCL的关注及研究要少于前交叉韧带.近年来高能量损伤致使PCL的损伤越来越多,学者们对PCL的关注度也在增加,进行了大量与PCL相关的实验,同时我们发现很多学者用动物的膝关节来代替人尸体进行体外生物力学实验,其中猪膝关节应用的最为广泛,基于这种情况,本文就猪膝关节的解剖结构与人的进行了比较,对其在体外生物力学实验中的应用进行了综述.     

平衡性训练对膝关节内侧副韧带损伤患者膝关节功能恢复的效果研究

目的:研究平衡性训练对膝关节内侧副韧带(MCL)损伤患者膝关节功能恢复的效果。方法:选取2014年8月至2016年8月北京体育大学运动员膝关节MCL损伤患者112例为研究对象,根据随机数字表法将其分为对照组(n=56)与观察组(n=56)。对照组予以常规康复训练干预,观察组则在对照组的基础上加用平衡性训练干预,两组患者干预时间均为4周,分别比较两组干预前和干预4周后膝关节功能变化情况、疼痛程度、膝关节平衡能力以及生活质量的变化。结果:干预后两组患者Lysholm评分均较干预前升高,且观察组明显高于对照组,差异有统计学意义(P0.05)。干预后两组患者视觉模拟(VAS)评分均明显低于干预前,且观察组明显低于对照组,差异均有统计学意义(均P0.05)。干预后,两组患者总体稳定指数(OSI)、前后方向的稳定指数(APSI)、左右方向的稳定指数(MLSI)水平均低于干预前,且观察组患者OSI、APSI、MLSI水平均低于对照组,差异均有统计学意义(均P0.05)。观察组患者满意度较对照组明显升高,差异有统计学意义(P0.05)。结论:为膝关节MCL损伤患者实施平衡性训练能较好地改善其膝关节功能,并缓解疼痛,同时可帮助其提高膝关节的平衡能力,增加了满意度,适于推广。     

Comparison of material properties in fascicle-bone units from human patellar tendon and knee ligaments

The fascicle material properties in bone-fascicle-bone units were determined for the anterior and posterior cruciate ligaments (ACL, PCL), the lateral collateral ligament (LCL) and the patellar tendon (PT) from three young human donor knees. Groups of fascicles from each tissue were isolated with intact bone ends and failed at a high strain rate in a saline bath at 37 degrees C. In each knee tested the load related material properties (linear modulus, maximum stress and energy density to maximum stress) for the patellar tendon were significantly larger than corresponding values for the cruciate and collateral ligaments. Bundles from different ligaments in the same knee were similar to each other in their mechanical behavior. In addition, no significant differences were present in the maximum strains recorded for any of the four tissue types examined. The results presented have implications in studies of ligament injury. They are also important in the design and use of synthetic and biological ligament replacements and in tissue and whole knee modeling.     

Bi-directional mechanical properties of the axillary pouch of the glenohumeral capsule: implications for modeling and surgical repair

The objective of this study was to determine the mechanical properties of the axillary pouch of the inferior glenohumeral ligament in the directions perpendicular (transverse) and parallel (longitudinal) to the longitudinal axis of the anterior band of the inferior glenohumeral ligament. A punch was used to excise one transverse and one longitudinal tissue sample from the axillary pouch of each cadaveric shoulder (n = 10). Each tissue sample was preconditioned and then a load-to-failure test was performed. All tissue samples exhibited the typical nonlinear behavior reported for ligaments and tendons. Significant differences (p < 0.05) were detected between the transverse and longitudinal tissue samples for ultimate stress (0.8 +/- 0.4 MPa and 2.0 +/- 1.0 MPa, respectively) and tangent modulus (5.4 +/- 2.9 MPa and 14.8 +/- 13.1 MPa, respectively). No significant differences (p > 0.05) were observed between the ultimate strain (transverse: 23.5 +/- 11.5%, longitudinal: 33.3 +/- 23.6%) and strain energy density (transverse: 10.8 +/- 8.5 MPa, longitudinal: 21.1 +/- 15.4 MPa) of the transverse and longitudinal tissue samples. The ultimate stress determined for the longitudinal axillary pouch tissue samples was comparable to a previous study that reported it to be 5.5 +/- 2.0 MPa. The ratio of the longitudinal to transverse moduli (3.3 +/- 2.8) is considerably less than that of the medial collateral ligament of the knee (30) and interosseous ligament of the forearm (385), suggesting that the axillary pouch functions to stabilize the joint in more than just one direction. Future models of the glenohumeral joint and surgical repair procedures should consider the properties of the axillary pouch in its transverse and longitudinal directions to fully describe the behavior of the inferior glenohumeral ligament.     

Effect of knee musculature on anterior cruciate ligament strain in vivo

Squatting is a commonly prescribed exercise following reconstruction of the anterior cruciate ligament (ACL). The objective of this paper was to measure the in vivo strain patterns of the normal ACL and the load at the knee for the simple squat and for squatting with a “sport cord”. A sport cord is a large elastic rubber tube used for added resistance. Strain patterns were deduced using displacement data from a Hall Effect Strain Transducer (HEST), while joint loads were determined by a mathematical model with inputs from a force plate and electrogoniometers. ACL strain for the free squat in one subject had a maximum of 2% at a knee angle of 10° and was slack for knee angles >17°. In squatting with a sport cord, peak strain was 1% at 10° and was slack at knee angles >14°. Since these peak strains are low, squatting appears to be a safe exercise for conservative rehabilitation of ACL reconstruction patients. In addition, the sport cord is a recommended augmentation to the activity. We believe that the decrease in strain with the sport cord results from added joint stiffness due to greater compressive forces at the tibiofemoral joint. This greater compressive force results from the approximately 10% increase in quadriceps activity. From shear force data predicted by the mathematical model, the maximum anterior drawer force for free squatting (50 N) was considerably less than for sport cord squatting (430 N). Therefore, the value of shear force at the tibiofemoral joint only partially determines the load placed on the ACL.     

Matrix metalloproteinase-13 expression in rabbit knee joint connective tissues: influence of maturation and response to injury.

The hypothesis of the present work was that expression of matrix metalloproteinase-13 (MMP-13, collagenase-3) would be induced during conditions involving important matrix remodeling such as ligament maturation, scar healing and joint instability. Therefore, MMP-13 expression in the medial collateral ligament (MCL) during the variable situations of tissue maturation and healing was assessed. MMP-13 expression in three intra-articular connective tissues of the knee (i.e. articular cartilage, menisci and synovium) following the transection of the anterior cruciate ligament of the knee was evaluated at 3 and 8 weeks post-injury. MMP-13 mRNA (semi-quantitative RT-PCR) and protein (immunohistochemistry and Western blotting) were detected in all of the tissues studied. Significantly higher MCL mRNA levels for MMP-13 were detected during the early phases of tissue maturation (i.e. 29 days in utero and 2-month-old rabbits) compared to later phases (5- and 12-month-old rabbits). This pattern of expression was recapitulated following MCL injury, with very high levels of expression in scar tissue at 3 weeks post-injury and then a decline to levels not significantly different from control values by 14 weeks. Elevated mRNA levels correlated with increased protein levels for MMP-13 in both menisci and synovium following the transection of the anterior cruciate ligament and during medial collateral ligament healing. These results indicate that MMP-13 expression is regulated by a number of variables and that high levels of expression occur in situations when connective tissue remodeling is very active.