Diagnosis of dystrophic lesions of the muscular and ligamentous tendons

The authors presented the results of investigations of the humoral, ulnar, hip, knee joints and calcanei in 4140 patients. Histology has shown that calcifications and ossifications at the sites of tendon fixation are localized in tendons. The substitution of tendinous tissue for a bone results from calcareous dystrophy. Three stages can be singled out: (I) the substitution of a tendon portion for a fibrillar cartilage; (II) the calcification of a cartilage; (III) the substitution of a calcified cartilage for a newly developed spongy bone. According to the preliminary data, similar changes can bep6 observed in ligaments, too. The clinical and x-ray examination have shown the frequency of tendinous and ligamentous lesions (tendinosis and ligamentosis) of different sites. They were shown to be pathology that may not be accompanied by pains. The appearance of the pain syndrome means the development of disease.     

Hip joint muscle forces during gait in patients with femoroacetabular impingement syndrome are associated with patient reported outcomes and cartilage composition

Femoroacetabular impingement syndrome (FAIS) consists of abnormal hip joint morphology and pain during activities of daily living. Abnormal gait mechanics and potentially abnormal muscle forces within FAI patients leads to articular cartilage damage. Therefore, there is a necessity to understand the effects of FAI on hip joint muscle forces during gait and the link between muscle forces, patient reported outcomes (PRO) and articular cartilage health. The purposes of this study were to assess: (1) hip muscle forces between FAI patients and healthy controls and (2) the associations between hip muscle forces with PRO and cartilage composition (T_1ρ/T₂ mapping) within FAI patients. Musculoskeletal simulations were used to estimate peak muscle forces during the stance phase of gait in 24 FAI patients and 24 healthy controls. Compared to controls, FAI patients ambulated with lower vasti (30% body-weight, p = 0.01) and higher sartorius (4.0% body-weight, p < 0.01) forces. Within FAI patients, lower peak gluteus medius, gluteus minimus, sartorius and iliopsoas forces were associated with worse hip joint pain and function (R = 0.43–0.70, p = 0–0.04), while lower muscle forces were associated with increased T_1ρ and T₂ values (i.e. altered cartilage composition) within the hip joint cartilage (R = −0.44 to −0.58, p = 0.006–0.05). Although FAI patients demonstrate abnormal muscle forces, it is unknown whether or not these altered muscle force patterns are associated with pain avoidance or weak musculature. Further investigation is required in order to better understand the effects of FAI on hip joint muscle forces and the associations with hip joint cartilage degeneration.     

Osteoarthritis of the hands, hips and knees in an Australian twin sample--evidence of association with the aggrecan VNTR polymorphism.

Age-related changes in the composition of the cartilage matrix may be associated with the development of osteoarthritis, a relatively late-onset disease characterised by the destruction of joint cartilage. In order to investigate whether differences in the VNTR polymorphic region of aggrecan affect cartilage functionality and therefore the development of osteoarthritis, we examined the aggrecan polymorphic genotypes of a sample of 134 Australian twins aged over 50 (including 34 monozygotic and 27 dizygotic twin pairs). Clinical measures of hand, hip and knee osteoarthritis, as well as self-reported bone and joint pain, were tested for association with the aggrecan polymorphism. The results were consistent with either a deleterious effect of allele 27, or a protective effect of alleles 25 and 28, providing some additional evidence for an association between the aggrecan VNTR polymorphism and osteoarthritis of the hands, hips and knees.     

髋关节撞击征的诊断和治疗*

摘要：髋关节撞击综合征(femoroacetabular impingement,FAI)是以髋关节解剖结构异常而引发的股骨近端和髋臼间发生异常碰 撞,从而导致髋关节盂唇和关节软骨的退行性变化,引起髋关节慢性疼痛的疾病。髋关节活动范围特别是屈曲和内旋受限,最终 发展为髋关节骨关节炎。FAI在我国国内为一个较新的概念,临床能得到诊断的病例不多,但实际病例很多,相当一部分的髋关节 疼痛是由撞击征造成,平常的药物止痛不能解除持续的撞击,最终会发生骨关节炎。由此早期的诊断及手术干预,可以消除疼痛, 防止骨关节炎的发生,进而推迟或消除关节置换手术是有巨大的经济和社会价值。     

Localization of types I, II, and III collagen mRNAs in developing human skeletal tissues by in situ hybridization

Paraffin sections of human skeletal tissues were studied in order to identify cells responsible for production of types I, II, and III collagens by in situ hybridization. Northern hybridization and sequence information were used to select restriction fragments of cDNA clones for the corresponding mRNAs to obtain probes with a minimum of cross-hybridization. The specificity of the probes was proven in hybridizations to sections of developing fingers: osteoblasts and chondrocytes, known to produce only one type of fibrillar collagen each (I and II, respectively) were only recognized by the corresponding cDNA probes. Smooth connective tissues exhibited variable hybridization intensities with types I and III collagen cDNA probes. The technique was used to localize the activity of type II collagen production in the different zones of cartilage during the growth of long bones. Visual inspection and grain counting revealed the highest levels of pro alpha 1(II) collagen mRNAs in chondrocytes of the lower proliferative and upper hypertrophic zones of the growth plate cartilage. This finding was confirmed by Northern blotting of RNAs isolated from epiphyseal (resting) cartilage and from growth zone cartilage. Analysis of the osseochondral junction revealed virtually no overlap between hybridization patterns obtained with probes specific for type I and type II collagen mRNAs. Only a fraction of the chondrocytes in the degenerative zone were recognized by the pro alpha 1(II) collagen cDNA probe, and none by the type I collagen cDNA probe. In the mineralizing zone virtually all cells were recognized by the type I collagen cDNA probe, but only very few scattered cells appeared to contain type II collagen mRNA. These data indicate that in situ hybridization is a valuable tool for identification of connective tissue cells which are actively producing different types of collagens at the various stages of development, differentiation, and growth.     

Stress distribution and consolidation in cartilage constituents is influenced by cyclic loading and osteoarthritic degeneration

The understanding of load support mechanisms in cartilage has evolved with computational models that better mimic the tissue ultrastructure. Fibril-reinforced poroelastic models can reproduce cartilage behaviour in a variety of test conditions and can be used to model tissue anisotropy as well as assess stress and pressure partitioning to the tissue constituents. The goal of this study was to examine the stress distribution in the fibrillar and non-fibrillar solid phase and pressure in the fluid phase of cartilage in axisymmetric models of a healthy and osteoarthritic hip joint. Material properties, based on values from the literature, were assigned to the fibrillar and poroelastic components of cartilage and cancellous and subchondral compact bone regions. A cyclic load representing walking was applied for 25 cycles. Contact stresses in the fibrillar and non-fibrillar solid phase supported less than 1% of the contact force and increased only minimally with load cycles. Simulated proteoglycan depletion increased stresses in the radial and tangential collagen fibrils, whereas fibrillation of the tangential fibrils resulted in increased compressive stress in the non-fibrillar component and tensile stress in the radial fibrils. However neither had an effect on fluid pressure. Subchondral sclerosis was found to have the largest effect, resulting in increased fluid pressure, non-fibrillar compressive stress, tangential fibril stress and greater cartilage consolidation. Subchondral bone stiffening may play an important role in the degenerative cascade and may adversely affect tissue repair and regeneration treatments.     

Serum Concentrations of Procollagen Type III Aminoterminal Peptide in Growing Dogs with Hip Dysplasia

The aim of the present study was to investigate the use of procollagen type III aminoterminal peptide (PIIINP) measurements in serum as an indicator of progress of fibrosis of coxofemoral joint capsules in hip dysplasia in immature dogs. High serum concentrations of PIIINP may indicate ongoing fibrosis with enhanced synthesis and deposition of fibrillar type III collagen, or an alteration in degradation and elimination of circulating PIIINP (Hørslev-Petersen et al. 1988a). Therefore, high concentrations of PIIINP in serum was expected in dogs with hip dysplasia, which is a developmental condition with capsular fibrosis and osteoarthritis (Gay et al. 1986).     

Effects of idealized joint geometry on finite element predictions of cartilage contact stresses in the hip

Computational models may have the ability to quantify the relationship between hip morphology, cartilage mechanics and osteoarthritis. Most models have assumed the hip joint to be a perfect ball and socket joint and have neglected deformation at the bone-cartilage interface. The objective of this study was to analyze finite element (FE) models of hip cartilage mechanics with varying degrees of simplified geometry and a model with a rigid bone material assumption to elucidate the effects on predictions of cartilage stress. A previously validated subject-specific FE model of a cadaveric hip joint was used as the basis for the models. Geometry for the bone-cartilage interface was either: (1) subject-specific (i.e. irregular), (2) spherical, or (3) a rotational conchoid. Cartilage was assigned either a varying (irregular) or constant thickness (smoothed). Loading conditions simulated walking, stair-climbing and descending stairs. FE predictions of contact stress for the simplified models were compared with predictions from the subject-specific model. Both spheres and conchoids provided a good approximation of native hip joint geometry (average fitting error ～0.5 mm). However, models with spherical/conchoid bone geometry and smoothed articulating cartilage surfaces grossly underestimated peak and average contact pressures (50% and 25% lower, respectively) and overestimated contact area when compared to the subject-specific FE model. Models incorporating subject-specific bone geometry with smoothed articulating cartilage also underestimated pressures and predicted evenly distributed patterns of contact. The model with rigid bones predicted much higher pressures than the subject-specific model with deformable bones. The results demonstrate that simplifications to the geometry of the bone-cartilage interface, cartilage surface and bone material properties can have a dramatic effect on the predicted magnitude and distribution of cartilage contact pressures in the hip joint.     

髋关节撞击征的诊断和治疗

髋关节撞击综合征（femoroacetabularimpingement,FAI）是以髋关节解剖结构异常而引发的股骨近端和髋臼间发生异常碰撞,从而导致髋关节孟唇和关节软骨的退行性变化,引起髋关节慢性疼痛的疾病。髋关节活动范围特别是屈曲和内旋受限,最终发展为髋关节骨关节炎。FAI在我国国内为一个较新的概念,临床能得到诊断的病例不多,但实际病例很多,相当一部分的髋关节疼痛是由撞击征造成,平常的药物止痛不能解除持续的撞击,最终会发生骨关节炎。由此早期的诊断及手术干预,可以消除疼痛,防止骨关节炎的发生。进而推迟或消除关节置换手术是有巨大的经济和社会价值。     

Immunolocalization of collagen types II and III in single fibrils of human articular cartilage.

Type II and III fibrillar collagens were localized by immunogold electron microscopy in resin sections of human femoral articular cartilage taken from the upper radial zone in specimens from patients with osteoarthritis. Tissue samples stabilized by high-pressure cryofixation were processed by freeze-substitution, either in acetone containing osmium or in methanol without chemical fixatives, before embedding in epoxy or Lowicryl resin, respectively. Ultrastructural preservation was superior with osmium-acetone, although it was not possible to localize collagens by this method. In contrast, in tissue prepared by low-temperature methods without chemical fixation, collagens were successfully localized with mono- or polyclonal antibodies to the helical (Types II and III) and amino-propeptide (Type III procollagen) domains of the molecule. Dual localization using secondary antibodies labeled with 5- or 10-nm gold particles demonstrated the presence of Types II and III collagen associated within single periodic banded fibrils. Collagen fibrils in articular cartilage are understood to be heteropolymers mainly of Types II, IX, and XI collagen. Our observations provide further evidence for the complexity of these assemblies, with the potential for interactions between at least 11 distinct collagen types as well as several noncollagenous components of the extracellular matrix.     

The interphalangeal area of Rana pipiens: a light and electron microscopic study of the development of a fibrocartilaginous joint (symphysis)

The development of the distal interphalangeal joint in Rana pipiens hind limb was studied by light and electron microscopy. The joint was found to be a symphysis since the two articular surfaces originally capped by hyaline cartilage were separated by a joint area filled with fibrous connective tissue which ultimately was replaced by fibrocartilage. Ultrastructural studies demonstrated that the joint area development was divided into three phases. Phase I was concerned with the undifferentiated mesenchymal cells, phase II with fibroblastic and chondroblastic development, and phase III with the appearance of fibrocartilage. Changes in the cytoplasmic organelles of fibroblasts and chondroblasts, surrounding extracellular matrix, and factors related to extracellular matrix formation were described and discussed.     

The importance of femur/acetabulum cartilage in the biomechanics of the intact hip: experimental and numerical assessment

Experimental studies have been made to study and validate the biomechanics of the pair femur/acetabulum considering both structures without the presence of cartilage. The main goal of this study was to validate a numerical model of the intact hip. Numerical and experimental models of the hip joint were developed with respect to the anatomical restrictions. Both iliac and femur bones were replicated based on composite replicas. Additionally, a thin layer of silicon rubber was used for the cartilage. A three-dimensional finite element model was developed and the boundary conditions of the models were applied according to the natural physiological constrains of the joint. The loads used in both models were used just for comparison purposes. The biomechanical behaviour of the models was assessed considering the maximum and minimum principal bone strains and von Mises stress. We analysed specific biomechanical parameters in the interior of the acetabular cavity and on femur's surface head to determine the role of the cartilage of the hip joint within the load transfer mechanism. The results of the study show that the stress observed in acetabular cavity was 8.3 to 9.2 MPa. When the cartilage is considered in the joint model, the absolute values of the maximum and minimum peak strains on the femur's head surface decrease simultaneously, and the strains are more uniformly distributed on both femur and iliac surfaces. With cartilage, the cortex strains increase in the medial side of the femur. We prove that finite element models of the intact hip joint can faithfully reproduce experimental models with a small difference of 7%.     

关节镜治疗髋关节疾病的临床研究

目的:研究髋关节镜治疗髋关节疾病的方法、疗效及适应证,探讨髋关节镜在髋关节疾病中的临床价值。方法:研究对象为86例有明显髋关节疼痛的患者,包括股骨头坏死(osteonecrosis,ON)(43%)、盂唇损伤(20%)、退行性关节病变(degenerative joint disease,DJD)(10%)、股骨头骨骺缺血性坏死(Legg-Calve'-Perthes,LCP)(10%)、髋关节游离体(10%)、髋关节疼痛(100%)、机械性损伤(78%)、运动损伤(56%)。对患者采用仰卧位进行髋关节镜检查,使用牵引床,300或700,前外侧入口。观察不同疾病在治疗后的预后结果。结果:所有患者均无并发症,平均随访时间30个月,有60%的患者疼痛症状得到缓解。盂唇(91%,P0.003)或LCP(89%,P0.05)患者疗效较好,而ON和DJD患者疼痛症状缓解较差,改善率仅为40%和44%。在吻合血管游离腓骨移植(free-vascularized fibular graft,FVEG)的患者中有34%在随访期间得到改善(P=0.003)。其中18名患者(21%)进行了全髋关节置换术。结论:髋关节镜手术对于游离体、盂唇损伤、局灶性软骨病变、晚期LCP后遗症患者有良好的治疗效果;对股骨头坏死的治疗效果不佳。     

The low permeability of healthy meniscus and labrum limit articular cartilage consolidation and maintain fluid load support in the knee and hip

The knee meniscus and hip labrum appear to be important for joint health, but the mechanisms by which these structures perform their functions are not fully understood. The fluid phase of articular cartilage provides compressive stiffness and aids in maintaining a low friction articulation. Healthy fibrocartilage, the tissue of meniscus and labrum, has a lower fluid permeability than articular cartilage. In this study we hypothesized that an important function of the knee meniscus and the hip labrum is to augment fluid retention in the articular cartilage of a mechanically loaded joint. Axisymmetric hyperporoelastic finite element models were analyzed for an idealized knee and an idealized hip. The results indicate that the meniscus maintained fluid pressure and inhibited fluid exudation in knee articular cartilage. Similar, but smaller, effects were seen with the labrum in the hip. Increasing the fibrocartilage permeability relative to that of articular cartilage gave a consolidation rate and loss of fluid load support comparable to that predicted by meniscectomy or labrectomy. The reduced articular cartilage fluid pressure that was calculated for the joint periphery is consistent with patterns of endochondral ossification and osteophyte formation in knee and hip osteoarthritis. High articular central strains and loss of fluid load support after meniscectomy could lead to fibrillation. An intact low-permeability fibrocartilage is important for limiting fluid exudation from articular cartilage in the hip and knee. This may be an important aspect of the role of fibrocartilage in protecting these joints from osteoarthritis.     

转化生长因子5在发育性髋关节发育不良中的作用研究进展

发育性髋关节发育不良(developmental dysplasia of the hip,DDH)是一种主要因髋臼、股骨近端和关节囊等存在结构性畸形而导致的不稳定关节病变,进而发展成为髋关节的脱位。髋关节内软骨发育不良、骨骼及肌腱的异常均可导致髋关节结构的畸形,最终造成DDH。因此,早期预防与诊断是DDH治疗的关键。研究表明,DDH具有遗传基础,其易感基因包括GDF5、HOXD9、COL2AL、PAPPA2等,其中遗传因子转化生长因子5(growth differentiation factor 5,GDF5)对软骨细胞的增殖、分化具有重要作用,是当前研究治疗DDH的热点之一。因而,了解GDF5基因对软骨发育及分化的影响,对于DDH的发病机制和治疗具有重要意义。基于此,综述了国内外近期探讨的GDF5在基因层面上对DDH的影响,以及通过关节内注射重组人GDF5等基于GDF5的DDH治疗方案,以期为DDH的临床治疗提供新的策略。     

Articular cartilage friction increases in hip joints after the removal of acetabular labrum

The acetabular labrum is believed to have a sealing function. However, a torn labrum may not effectively prevent joint fluid from escaping a compressed joint, resulting in impaired lubrication. We aimed to understand the role of the acetabular labrum in maintaining a low friction environment in the hip joint. We did this by measuring the resistance to rotation (RTR) of the hip, which reflects the friction of the articular cartilage surface, following focal and complete labrectomy. Five cadaveric hips without evidence of osteoarthritis and impingement were tested. We measured resistance to rotation of the hip joint during 0.5, 1, 2, and 3 times body weight (BW) cyclic loading in the intact hip, and after focal and complete labrectomy. Resistance to rotation, which reflects articular cartilage friction in an intact hip was significantly increased following focal labrectomy at 1-3 BW loading, and following complete labrectomy at all load levels. The acetabular labrum appears to maintain a low friction environment, possibly by sealing the joint from fluid exudation. Even focal labrectomy may result in increased joint friction, a condition that may be detrimental to articular cartilage and lead to osteoarthritis.     

The head cartilage of cephalopods II. Ultrastructure of isolated native collagen fibrils and of polymeric aggregates obtained in Vitro: Comparison with the cartilage of mammals

Native collagen fibrils were isolated from cephalopod head cartilage and mammal hyaline cartilage. The analysis with TEM after positive and negative staining demonstrated that the fibrils have a periodic structure similar to that of fibrillar type I collagen of mammals. The banding pattern of polymeric forms (SLS, FLS) obtained in vitro from squid cartilage collagen was remarkably different from the analogous forms of mammal collagen types I and II.     

A Three-Dimensional Finite Element Model for Biomechanical Analysis of the Hip

The objective of this study was to construct a three-dimensional (3D) finite element model of the hip. The images of the hip were obtained from Chinese visible human dataset. The hip model includes acetabular bone, cartilage, labrum, and bone. The cartilage of femoral head was constructed using the AutoCAD and Solidworks software. The hip model was imported into ABAQUS analysis system. The contact surface of the hip joint was meshed. To verify the model, the single leg peak force was loaded, and contact area of the cartilage and labrum of the hip and pressure distribution in these structures were observed. The constructed 3D hip model reflected the real hip anatomy. Further, this model reflected biomechanical behavior similar to previous studies. In conclusion, this 3D finite element hip model avoids the disadvantages of other construction methods, such as imprecision of cartilage construction and the absence of labrum. Further, it provides basic data critical for accurately modeling normal and abnormal loads, and the effects of abnormal loads on the hip.     

Development and aging of the articular cartilage of the rabbit knee joint: Distribution of biglycan, decorin, and matrilin-1.

We determined the distributions of the small proteoglycans biglycan and decorin and the glycoprotein matrilin-1 (cartilage matrix protein) during development and aging of articular cartilage in the rabbit knee joint. Before cavitation, the matrices of the interzone and the adjacent epiphyseal cartilage do not contain biglycan or decorin, but some chondrocytes express their mRNAs. Matrilin-1 is found only in the deeper epiphyseal cartilage. After cavitation, biglycan and decorin are detected in the presumptive articular cartilage, but there is no matrilin-1. All are present in the underlying epiphyseal cartilage. In the neonate, the epiphyseal cartilage is ossified and the articular cartilage becomes a discrete layer. Biglycan and decorin accumulate in the articular cartilage, but matrilin-1 remains confined to the residual epiphyseal cartilage. In the adult, the distributions of biglycan and decorin are highly variable. Decorin tends to be confined to the central region; matrilin-1 is absent. The findings indicate that the articular and epiphyseal cartilages are different from the earliest developmental stages. The epiphyseal cartilage can be identified by its possession of matrilin-1. Epiphyseal cartilage is removed during development to leave the articular cartilage. The relationships between the distributions of decorin and matrilin-1 and the fibrillar collagens are discussed. (J Histochem Cytochem 47:1603-1615, 1999)