The hip joint: the fibrillar collagens associated with development and ageing in the rabbit

The fibrillar collagens associated with the articular cartilages, joint capsule and ligamentum teres of the rabbit hip joint were characterised from the 17 d fetus to the 2-y-old adult by immunohistochemical methods. Initially the putative articular cartilage contains types I, III and V collagens, but when cavitation is complete in the 25 d fetus, type II collagen appears. In the 17 d fetus, the cells of the chondrogenous layers express type I collagen mRNA, but not that of type II collagen. Types III and V collagens are present throughout life, particularly pericellularly. Type I collagen is lost. In all respects, the articular cartilage of the hip joint is similar to that of the knee. The joint capsule contains types I, III and V collagens. In the fetus the ligamentum teres contains types I and V collagens and the cells express type I collagen mRNA; type III collagen is confined mainly to its surface and insertions. After birth, the same distribution remains, but there is more type III collagen in the ligament, proper. The attachment to the cartilage of the head of the femur is marked only by fibres of type I collagen traversing the cartilage; the attachment cannot be distinguished in preparations localising types III and V collagens. The attachment to the bone at the lip of the acetabulum is via fibres of types I and V collagens and little type III is present. The ligament is covered by a sheath of types III and V collagens. Type II collagen was not located in any part of the ligamentum teres. The distribution of collagens in the ligamentum teres is similar to that in the collateral ligaments of the knee. Its insertions are unusual because no fibrocartilage was detected.     

Ligament repair: a molecular and immunohistological characterization

The anterior cruciate ligament (ACL) is the most commonly injured tissue of the human knee. Its poor ability to regenerate after injury represents a challenge to ligament tissue engineering. An understanding of the molecular composition of the structures used for its repair is essential for clinical assessments and for the implementation of tissue engineering strategies. The objective of this study was to evaluate, both at gene and protein levels, the expression of characteristic molecules in human ACL, patellar, semitendinosus and gracilis tendons and in the ligament reconstructed with patellar or semitendinosus and gracilis tendons. We demonstrated that primary ACL and tendon tissues all express collagen I, II, Sox-9, tenascin-C and aggrecan. Collagen X expression was detected at very low levels or undetectable. Cathepsin B, MMP-1 and MMP-13 were expressed at higher levels in the ACL reconstructed by the two tendons, showing that a remodeling process occurs during "ligamentization". Both our molecular and immunohistochemical evaluations did not reveal significative differences between the tendons and ligaments analyzed. However, ACL reconstructed with semitendinosus and gracilis tendon seems to present a higher expression of collagen type II when compared to that reconstructed with patellar tendon. This study could give a reasonable identification of genetic and protein markers specific to tendon/ligament tissues and be helpful in testing tissue engineering approaches for ACL reconstruction.     

股四头肌腱的临床应用解剖

目的　为临床应用股四头肌腱重建膝关节交叉韧带提供临床解剖学资料。 方法　在10具成人尸体标本上（20只膝关节）解剖观察股四头肌腱的形态和走行关系以及在髌骨附着点的解剖学特点,测量股直肌腱起止点宽度、长度以及髌骨上极的厚度。 结果　股直肌止点的宽度为（3.20±0.33）cm。起点的宽度为（1.28±0.25）cm。完全为腱性组织的长度为（6.96±0.80）cm。股直肌腱近侧端约4/5完全游离,远侧端约1/5与股外侧肌和股中间肌融合,共同构成股四头肌腱,附着于髌骨上极前方约3/4部分。髌上极的平均厚度为(2.22±0.14)cm。 结论　股四头肌腱的的解剖学特点,完全使其可以作为临床上行膝关节交叉韧带重建的供区之一。     

Variations in internal structure,composition and protein distribution between intra‐ and extra‐articular knee ligaments and tendons

Tendons and ligaments play key roles in the musculoskeletal system in both man and animals. Both tissues can undergo traumatic injury, age‐related degeneration and chronic disease, causing discomfort, pain and increased susceptibility to wider degenerative joint disease. To date, tendon and ligament ultrastructural biology is relatively under‐studied in healthy, non‐diseased tissues. This information is essential to understand the pathology of these tissues with regard to function‐related injury and to assist with the future development of tissue‐engineered tendon and ligament structures. This study investigated the morphological, compositional and extracellular matrix protein distribution differences between tendons and ligaments around the non‐diseased canine stifle joint. The morphological, structural characteristics of different regions of the periarticular tendons and ligaments (the intra‐articular anterior cruciate ligament, the extra‐articular medial collateral ligament, the positional long digital extensor tendon and energy‐storing superficial digital flexor tendons) were identified using a novel semi‐objective histological scoring analysis and by determining their biochemical composition. Protein distribution of extracellular matrix collagens, proteoglycans and elastic fibre proteins in anterior cruciate ligament and long digital extensor tendon were also determined using immunostaining techniques. The anterior cruciate ligament was found to have significant morphological differences in comparison with the other three tissues, including less compact collagen architecture, differences in cell nuclei phenotype and increased glycosaminoglycan and elastin content. Intra‐ and interobserver differences of histology scoring resulted in an average score 0.7, indicative of good agreement between observers. Statistically significant differences were also found in the extracellular matrix composition in terms of glycosaminoglycan and elastin content, being more prominent in the anterior cruciate ligament than in the other three tissues. A different distribution of several extracellular matrix proteins was also found between long digital extensor tendon and anterior cruciate ligament, with a significantly increased immunostaining of aggrecan and versican in the anterior cruciate ligament. These findings directly relate to the different functions of tendon and ligament and indicate that the intra‐articular anterior cruciate ligament is subjected to more compressive forces, reflecting an adaptive response to normal or increased loads and resulting in different extracellular matrix composition and arrangement to protect the tissue from damage.     

Bilateral dislocation of the knee with rupture of both patellar tendons. A case report

Knee dislocations are rare injuries caused by violent trauma. Damage to soft tissues and ligament lesions almost always accompany the injury. Vascular compromise further complicates the situation. We report a case of bilateral posterior knee dislocation with traumatic rupture of both patellar tendons. Treatment consisted of external fixation of both knees. Vascular compromise resolved with reduction and traction pins were placed on both patellae which were connected to the external fixators on following days. Primary repair of patellar tendon was undertaken after gradual distal repositioning of patella. The result is successful with full range of motion. Rupture of patellar tendon should be considered with posterior dislocation of the knee. External fixators provide quick stabilization in case of vascular compromise and can be modified to provide a traction system for distal repositioning of patella which allows primary repair of the patellar tendon.     

Infrapatellar fat pad may be with tendon repairing ability and closely related with the developing process of patella Baja

Patella Baja, as a common complication of knee trauma or knee surgery, was very difficult to deal with, and scarring and shortening of the patellar tendon were looked on as the most important reason for it. Infrapatellar fat pad, also known as Hoffa’s fat pad was traditionally regarded as with only buffering and lubricating functions in knee joints, which can limit the knee’s excessive activities, absorb shocks from the anterior knee and reduces friction between the patellar tendon and the tibia, it should be with direct protection function and avoid the damage of patella tendon. Recently, a large number of studies had shown that adipose tissue was an accessible and abundant source of mesenchymal stem cells for tissue engineering. Adipose derived stem cells (ADSCs) can be induced to differentiate into adipocytes, osteoblasts, nerve cells, tendon cells and so on. In addition, interestingly, infrapatellar fat pad were just located behind the patellar tendon, and SDF-1 (stromal cell-derived factor-1), as a powerful cytokine that regulates inflammatory cell recruitment and stem cell homing, was unregulated after ligament injury, so there may be a certain correlation between ADSCs from infrapatellar fat pad and injured tendons, maybe ADSCs from infrapatellar fat pad can biologically repair injured tendons when patella tendon was damaged. We hypothesized injured patella tendon repairing should include not only the self-repairing of the tendon, but also the biological repairing from ADSCs in infrapatellar fat pad. When both of the repairing failed to repair the damage of the tendon, patellar tendon may begin to shrink and scar, which will result in patella Baja. In our opinion, healthy infrapatellar fat pad was with direct protection function of patella tendon and full of rich ADSCs, which may play an important part in patella tendon repairing and the developing process of patella Baja.     

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。     

The morphometry of patella and patellar ligament during the fetal period

This study aims to determine the development and morphology of the patella and patellar tendon and to obtain morphometric data about these structures during the fetal period. One hundred five human fetuses (55 males and 50 females) aged 9-40 weeks were used in this study. Fetuses were divided into four groups between gestational weeks; Group I (9-12 weeks), Group II (13-25 weeks), Group III (26-37 weeks), and Group IV (38-40 weeks). The patella and patellar ligament were exposed via anatomical dissection; the dimensions (length, width, thickness) and the width of the lateral and medial articular surfaces of the patella, and the length and width of the patellar ligament, were measured using a Vernier's caliper. No significant differences were observed between genders or sides for any of the parameters (P > 0.05), and a significant correlation was found between gestational age and all parameters (P < 0.001). All parameters of the patella and patellar ligament were found to be different statistically between trimesters (P < 0.05). This study reveals the development, morphological changes, and the morphometric measurements of the patella and patellar ligament during the fetal period. We hope that the present results can be useful for future studies.     

保留止点自体肌腱移植治疗陈旧性髌韧带断裂

背景：髌韧带在膝关节的运动中起着非常重要的的作用,因其断裂比较少见,临床上误诊率较高。目前重建髌韧带的方法较多,疗效报道不一,治疗不当容易出现髌骨位置不良,会严重影响膝关节的功能。 目的：探讨保留止点自体肌腱移植治疗陈旧性髌韧带断裂的临床疗效。 方法：对8例单侧陈旧性髌韧带断裂的患者行保留止点的半肌腱、股薄肌重建髌韧带,髌韧带重建后行半环形石膏后托固定屈膝15°1周,髌韧带重建后2周拆除切口缝线,3周去除石膏行股四头肌等长等张练习,6周时佩戴可调节膝关节护具进行膝关节活动度锻炼,3次/d,每周增加10°。髌韧带重建3个月后允许完全负重行走。 结果与结论：所有患者髌韧带重建后无并发症,X射线示髌骨恢复正常高度。膝关节功能恢复良好。所有患者髌韧带重建后24个月行走2 km以上膝关节无不适。与髌韧带重建前相比,髌韧带重建后24个月患者的Lysholm评分明显增加(P < 0.05),说明保留止点的半腱肌、股薄肌重建髌韧带可重建治疗陈旧性髌韧带断裂。     

带血供大收肌腱转位修复膝关节韧带的应用解剖及临床 …

目的：报道以膝上内侧血管为蒂大收肌腱转位重建膝关节韧带断裂缺损的应用解剖及术式设计。方法：４０侧经动脉灌注红色乳胶成人标本,解剖观测大收肌腱的形态及其血供,２侧新鲜下肢标本模拟手术设计。以膝上内侧血管为蒂大收肌腱转位修复膝关节韧带断裂缺损。结果：应用带血供大收肌腱转位修复胫侧副韧带３０例,胫侧副韧带和前交叉韧带８例,胫侧副韧带和后交叉韧带４例,多韧带损伤１例,经随访疗效为满意。结论：大收肌腱与膝关     

The arterial supply of the patellar tendon: Anatomical study with clinical implications for knee surgery

The middle‐third of the patellar tendon (PT) is well‐established as a potential graft for cruciate ligament reconstruction, but there is little anatomical basis for its use. Although studies on PT vascular anatomy have focused on the risk to tendon pedicles from surgical approaches and knee pathophysiology, the significance of its blood supply to grafting has not been adequately explored previously. This investigation explores both the intrinsic and extrinsic arterial anatomy of the PT, as relevant to the PT graft. Ten fresh cadaveric lower limbs underwent angiographic injection of the common femoral artery with radio‐opaque lead oxide. Each tendon was carefully dissected, underwent plain radiography and subsequently schematically reconstructed. The PT demonstrated a well‐developed and consistent vascularity from three main sources: antero‐proximally, mainly by the inferior‐lateral genicular artery; antero‐distally via a choke‐anastomotic arch between the anterior tibial recurrent and inferior medial genicular arteries; and posteriorly via the retro‐patellar anastomotic arch in Hoffa's fat pad. Two patterns of pedicles formed this arch: inferior‐lateral and descending genicular arteries (Type‐I); superior‐lateral, inferior‐lateral, and superior‐medial genicular arteries (Type‐II). Both types supplied the posterior PT, with the majority of vessels descending to its middle‐third. The middle‐third PT has a richer intrinsic vascularity, which may enhance its ingrowth as a graft, and supports its conventional use in cruciate ligament reconstruction. The pedicles supplying the PT are endangered during procedures where Hoffa's fat pad is removed including certain techniques of PT harvest and total knee arthroplasty. Clin. Anat. 22:371–376, 2009. © 2009 Wiley‐Liss, Inc.     

Patellar tendon injury following anterior cruciate reconstruction

Rupture of the patellar tendon following the use of its central one-third in Anterior Cruciate Ligament Reconstruction is a well-recognised though rare complication. Usually this takes the form of a tendinous rupture at one or other pole of the tendon, or a fracture of the patella. We report a unique case of detachment of the medial slip of the patellar tendon through a fracture of the medial patella and of the lateral slip through a fracture of the tibial tuberosity following the use of the central one-third of the tendon for anterior cruciate reconstruction.     

Correlation between patella and patellar tendon width: An anatomic study

Anterior cruciate ligament (ACL) rupture is a common injury among orthopaedic patients with many different treatment modalities including bone-patella-bone autograft (BPBA) ACL reconstruction. Patella tendon width has been reported to be a predictor of recovery speed and success following BPBA repair. This study reports on the strength of the relationship between patella width and patella tendon width. Twenty fresh frozen cadavers were included in the study. Patella and patellar tendon measurements were recorded at the midpoint of the patellar tendon. Pearson correlation and linear regression were used to determine the relationship between patella width and patellar tendon width. Bivariate correlations with 95% confidence intervals and coefficients of determination (R(2) ) are reported. The study used 20 cadavers, 12 men and 8 women with a mean age of 72 (standard deviation [SD] = 12; range = 44 to 87). The mean patella width was 49.24mm (SD = 4.11; range 42.33mm-56.33mm) while the mean patellar tendon width was 26.10mm (SD = 3.31; range 18.33mm-33.33mm). The correlation between patella width and patellar tendon width was 0.67 (95% confidence interval = 0.45 - 0.81). R(2), the percent of variance in patellar tendon width accounted for by patella width, was 0.45. The regression equation for predicting patellar tendon width (y) yielded a formula of y = 0.536 + -0.316 × patella width. A moderate correlation exists between patella width and patellar tendon width. Our data suggests that this correlation is strongest with wider patellas and is more loosely associated with smaller patellas.     

Biomechanics of the knee joint in flexion under various quadriceps forces

Bioemchanics of the entire knee joint including tibiofemoral and patellofemoral joints were investigated at different flexion angles (0° to 90°) and quadriceps forces (3, 137, and 411 N). In particular, the effect of changes in location and magnitude of restraining force that counterbalances the isometric extensor moment on predictions was investigated. The model consisted of three bony structures and their articular cartilage layers, menisci, principal ligaments, patellar tendon, and quadriceps muscle. Quadriceps forces significantly increased the anterior cruciate ligament, patellar tendon, and contact forces/areas as well as the joint resistant moment. Joint flexion, however, substantially diminished them all with the exception of the patellofemoral contact force/area that markedly increased in flexion. When resisting extensor moment by a force applied on the tibia, the force in cruciate ligaments and tibial translation significantly altered as a function of magnitude and location of the restraining force. Quadriceps activation generated large ACL forces at full extension suggesting that post ACL reconstruction exercises should avoid large quadriceps exertions at near full extension angles. In isometric extension exercises against a force on the tibia, larger restraining force and its more proximal location to the joint substantially decreased forces in the anterior cruciate ligament at small flexion angles whereas they significantly increased forces in the posterior cruciate ligament at larger flexion angles.     

Nerve injury during anterior cruciate ligament reconstruction: A comparison between patellar and hamstring tendon grafts harvest

Background

Tendon harvesting for anterior cruciate ligament reconstruction often injures sensory branches of the saphenous nerve. The reports on the prevalence of these injuries are scarce, while the implications on patient satisfaction are not known. Our objective was to compare the prevalence of sensory nerve injuries in patellar to hamstring autograft harvesting for anterior cruciate ligament reconstructions and follow up their postoperative course.

Development of functionally distinct fibrocartilages at two sites in the quadriceps tendon of the rat: the suprapatella and the attachment to the patella

Summary This paper describes the post-natal development of two fibrocartilages in the quadriceps tendon of the rat. The compression-resisting fibrocartilage of the suprapatella was derived from a cell population present in neonates and positioned on the deep surface of the tendon of vastus intermedius. The cells secreted a metachromatic, coarsely fibrous extracellular matrix that was rich in chondroitin sulphate but lacked keratan sulphate or type II collagen. The cells themselves accumulated large quantities of vimentin. The adult form of the suprapatella was attained 8 weeks after birth. The fibrocartilage of the attachment zone of the quadriceps tendon to the patella was formed in a different manner. In animals up to 4 weeks of age, the quadriceps tendon inserted directly into the cartilage model of the patella. When later this was resorbed, and replaced by bone, the cartilage at the attachment zone remained, along with that of the articular surface of the patella. Attachment-zone fibrocartilage was therefore rich in type II collagen, unlike that of the suprapatella. Thus two functionally different fibrocartilages have been shown to have different origins, even when separated by only a short distance within the same tendon. The compositional differences between attachment-zone and compressive region fibrocartilages are also due to their different origins.     

Anatomical bases of patellar tendon grafts used in anterior cruciate ligament reconstruction

In 24 fresh specimens the blood-supply of the infrapatellar fat-pad was investigated by injection. In some of the specimens, Clancy's pedicled patellar tendon graft for anterior cruciate ligament reconstruction had been performed before injection. The fat-pad is supplied by vessels forming a plexus supplying the tendon. In the tendon grafts injected after Clancy's procedure, no vessels were found penetrating the patellar tendon at its patellar and tibial attachments. Filled vessels were found by histologic methods and the Spalteholz technique.     

髌韧带血供及其在重建膝交叉韧带中的意义

目的：探讨髌韧带血供的特点,为临床交叉韧带移植重建提供应用解剖学资料。方法：通过对成人和胎儿下肢标本经股动脉红色乳胶灌注并解剖观察,以及胎儿墨汁灌注组织透明和组织切片等方法,观察髌韧带的动脉来源、分布特点,并测量胎儿韧带内微血管密度。结果：髌韧带的动脉来自膝下外动脉、胫前返动脉、膝降动脉和膝下内侧动脉的分支;胎儿髌韧带不同区域微血管密度不同,以韧带中心部位密度最低。结论：髌韧带中心部为相对乏血管区,对以髌韧带为替代物行交叉韧带重建有重要的临床意义。     

Right ventricular false tendons, a cadaveric approach

Left ventricular false tendons (LFTs) have been extensively described and recognized by gross anatomic studies. However, there is very little information available regarding right ventricular false tendons (RFTs). The aim of our study, therefore, was to explore and delineate the morphology, topography and morphometry of the RFTs, and provide a comprehensive picture of their anatomy across a broad range of specimens. We identified 35/100 heart specimens containing right ventricular RFTs and classified them into five types. In Type I (21, 47.7%) the RFTs, was located between the ventricular septum and the anterior papillary muscle; in Type II (11, 22.9%) between ventricular septum and the posterior papillary muscle; in Type III (7, 14.5%) between the anterior leaflet of the tricuspid valve and the right ventricular free wall; in Type IV (5, 10.4%) between the posterior papillary muscle and the ventricular free wall; and lastly, in Type V (4, 8.3%) between the anterior papillary muscle and ventricular free wall. The mean length of the RFTs was 18 ± 7 mm with a mean diameter of 1.4 ± 05 mm. Histologic examination with Masson trichrome and PAS revealed that 20 (41.6%) of the 48 RFTs carried conduction tissue fibers. The presence of conduction tissue fibers within the RFTs was limited to Types I, III, and IV. In Types II and V the RFTs resembled fibrous structures in contrast with Type I, II and IV, which were composed more of muscular fibers, including conduction tissue fibers. RFTs containing conduction tissue fibers were identified, which may implicate them in the appearance of arrhythmias.     

前交叉韧带移植物选择及重建中的相关问题

背景：前交叉韧带移植物的选择受到多种因素的影响和制约,目前仍然存在争议。 目的：综述近期前交叉韧带重建移植物的选择及相关进展。 方法：由第一作者检索1995/2009 PubMed数据与维普数据库有关前交叉韧带重建中单、双束重建的比较,移植物选择,前交叉韧带损伤与骨关节炎相关性及前交叉韧带重建与本体感觉功能恢复相关性的文献。 结果与结论：在前交叉韧带重建中,单束与双束重建在临床疗效上目前并无显著差别;在移植物的选择上,目前仍然存在争议,骨-髌腱-骨以及四股腘绳肌自体移植物仍为前交叉韧带重建中的首选,带骨或不带骨的股四头肌肌腱、各种异体移植物和人工肌腱也逐渐被广泛使用于临床。从目前的各种报道分析,发生早期骨关节炎的危险因素中最重要的是半月板损伤,而非前交叉韧带损伤;对于施行前交叉韧带重建的患者,在治疗过程中应同时重视本体感觉功能的恢复。