膝关节后交叉韧带损伤对侧副韧带生物力学的影响

背景：目前对膝关节后交叉韧带损伤后的研究多集中于软骨、后外侧结构及关节的松弛度等方面。 目的：观察后交叉韧带断裂对膝关节内、外侧副韧带生物力学的影响。 方法：取12具正常成人新鲜尸体膝关节标本,在200 N载荷下,测试膝关节屈曲0°,30°,60°,90°位时,内、外侧副韧带中点的应变,后将12具标本的后交叉韧带全部切断再进行相同的测试。 结果与结论：膝屈曲0°和30°位时,后交叉韧带断裂前后内、外侧副韧带中点的应变均为压应变,且差异无显著性意义 (P > 0.05);膝屈曲30°~90°位时,内侧副韧带中点的应变随着角度增加而逐渐增大;膝屈曲60°和90°位时,后交叉韧带断裂后拉应变较断裂前明显增大(P < 0.05),其中内侧副韧带中点的应变均为拉应变,而外侧副韧带中点的应变在后交叉韧带完整情况下膝屈曲60°时为压应变。说明后交叉韧带完全断裂对30°内的膝关节运动无明显影响,但是随着屈曲角度的增加,内、外侧副韧带受到的影响逐渐增大。     

Characterization of collagenous and elastic fiber systems and microvasculature of human cruciate ligaments: An electronmicroscopic and stereologic study

The cruciate ligaments of 35 human knee joints were analyzed by the combined use of immunohistochemistry and transmission and scanning electron microscopy. The results were verified by morphometric analyses. The anterior cruciate ligament (ACL) had a more twisted and complex architecture compared to the posterior cruciate ligament (PCL). The PCL showed significantly (p < 0,05) thicker fibril diameters (x = 84,2 nm, s = 25,8 nm vs. x = 79,3 nm, s = 19,9 nm) and a higher total cross-sectional area (252,00 mm² vs. 208,0. 5 mm²) than the ACL. In both ligaments, type III collagen was detected using monoclonal antibodies. The ACL revealed more type VI but less type IV collagen than the PCL. The vascularization of the ACL revealed an age-dependent pattern and was significantly (p < 0,001) less well marked than in the PCL. The results reflect the poor vascular supply of the ACL in the human knee joint. The complex collagen architecture and the lower vascularization of the ACL in comparison with the PCL may contribute to poor surgical results after traumatic anterior cruciate ligament rupture. © 1993 Wiley-Liss, Inc.     

A biochemical study of the distribution of collagen and its crosslinks in knee ligaments and the patellar tendon

Purpose: The purpose of this study was to investigate biochemical differences in collagen crosslinks from different locations within the ligaments and a tendon of the human knee.

Materials and Methods: The anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), lateral collateral ligament (LCL), and patellar tendon (PT) were obtained from 24 cadavers (13 men and 11 women) whose average age at the time of death was 84.8 years. Ligaments and PT samples were obtained from the femoral and tibial insertions and the midsubstance. Hydroxyproline (Hyp) and collagen crosslinks, including pyridinoline (Pyr) and pentosidine (Pen), were compared among the different sites.

Results: The midsubstance Hyp concentration was greater than at the femoral and tibial insertions in the ACL (p?=?0.00124 and 0.000255, respectively) and PCL (p?=?0.00036 and 0.042, respectively). The Pyr:collagen ratio did not differ among sites in any of the ligaments or PT. The Pen:collagen ratio at the midsubstance was greater than at the femoral and tibial insertions in the ACL (p?=?0.00022 and 0.00025, respectively) and LCL (p?=?0.000081 and 0.000021, respectively) and was greater at the femoral insertion in the MCL (p?=?0.00010).

Conclusions: The mature collagen crosslink Pyr was not different in distribution in knee ligaments and the PT. Pen increased at the midsubstance ligaments and the PT. As increased Pen may represent ligament degeneration, this may indicate that degeneration may progress more rapidly at the midsubstance than at the insertion sites of a ligament.     

Further studies on cruciate and collateral knee ligaments en adult broiler fowls

In order to determine whether degenerative changes in knee ligaments precede or follow their rupture, the knee joints of 55 adult male broiler breeding fowls have been studied. All birds were between 60 and 62 weeks old when examined. Dissections at autopsy revealed whether collateral or cruciate ligaments were deranged, but only intact ligaments were processed for histo-pathological examination. Degenerative lesions were observed in intact ligaments at sites corresponding to regions where rupture normally occurs. These sites differ for medial collateral and cruciate ligaments. There was an increased frequency, with perhaps increased severity, of lesions in ligaments of unstable joints. Severe degenerative changes also occurred in one ligament of a joint where all other ligaments were intact. Degenerative changes and thus rupture of knee ligaments are thought to be a consequence of repetitive trauma with joint instability accentuating such trauma.     

Ultrastructural changes of the patellar tendon as a cruciate ligament substitute (one year and two year results)

In four black-faced sheep, the posterior cruciate ligament was replaced with a free autogenous patellar tendon transplant. Tissue samples from the transplants were investigated by light and electron microscopy 1 year and 2 years after surgery. The normal contralateral posterior cruciate ligament and the normal contralateral patellar tendon were used as controls. The structural differences concerned cells, collagen fibrils, elastic tissue and proteoglycans. Most of the cells of the contralateral patellar tendon were spindle-shaped, whereas those of the transplant were frequently chondroid. In the central region of the transplant as well as in the area far from the bone, cell degenerations, and occasionally hypo- or even acellular zones were found. Measurements of the diameter of collagen fibrils in both contralateral patellar tendon and posterior cruciate ligament showed a more or less pronounced bimodal distribution. A unimodal distribution with mainly thin fibrils (20-60 nm) was demonstrated in the transplant tissue which also revealed some morphological alterations of the collagen fibrils. Thin elastic fibers (microfibrils and amorphous material) were randomly scattered among the collagen fibrils of the control samples, bundles of microfibrils (without amorphous material) characterized the transplant. Staining with Alcian blue in the presence of 0.3 M MgCl2 demonstrated a close relationship between proteoglycans and collagen fibrils as well as elastic components in patellar tendon. This arrangement was lost in the transplant where abundant proteoglycans were revealed which, however, composed a tight irregular network between the collagen fibrils. The results serve as a baseline for understanding the impaired biochemical properties of a free autogenous patellar tendon transplant.     

Investigation of the collagen fibril distribution in the medial collateral ligament in a rat knee model

This study compared the collagen fibril diameter distribution among six anatomical sites of the rat medial collateral ligament (MCL). Ultrathin MCL sections from 4 male Sprague-Dawley rats were examined electron microscopically. With an automated quantitation method, 41,638 fibrils were measured and compared among the periphery and core regions of the femoral, middle, and tibial portions of the MCL. Results demonstrated significant difference (p < .0033) in mean fibril diameter distribution among the six sites. The mass-averaged diameters of the core and peripheral fibrils were between 175.53 to 190.82 nm and 88.47 to 109.18 nm, respectively, with the peripheral fibrils more homogeneous in size. The fibrils occupied 36.7% to 57.1% of the cross-sectional area of the ligament. About 50% of the fibrils had an oblique factor of 0.8-1.0, implying that most fibrils were aligned longitudinally. This study has provided a detailed profile of the collagen fibril distributions in rat MCL.     

Investigation of the Collagen Fibril Distribution in the Medial Collateral Ligament in a Rat Knee Model

This study compared the collagen fibril diameter distribution among six anatomical sites of the rat medial collateral ligament (MCL). Ultrathin MCL sections from 4 male Sparague-Dawley rats were examined electron microscopically. With an automated quantitation method, 41,638 fibrils were measured and compared among the periphery and core regions of the femoral, middle, and tibial portions of the MCL. Results demonstrated significant difference ( p < .0033) in mean fibril diameter distribution among the six sites. The mass-averaged diameters of the core and peripheral fibrils were between 175.53 to 190.82 nm and 88.47 to 109.18 nm, respectively, with the peripheral fibrils more homogeneous in size. The fibrils occupied 36.7% to 57.1% of the cross-sectional area of the ligament. About 50% of the fibrils had an oblique factor of 0.8-1.0, implying that most fibrils were aligned longitudinally. This study has provided a detailed profile of the collagen fibril distributions in rat MCL.     

膝关节脱位致多韧带损伤Ⅰ期修复重建的疗效

目的:探讨膝关节脱位致膝关节前、后交叉韧带及内侧副韧带损伤后一期修复的疗效.方法:回顾性分析28例膝关节脱位致膝关节前、后交叉韧带损伤及合并内侧副韧带Ⅲ度损伤或完全断裂的患者行Ⅰ期修复重建的疗效.其中车祸事故伤22例,军事训练伤4例,高台坠落伤2例.损伤至手术时间6～17(平均7)d.膝关节Lysholm评分为21.7±6.52,国际膝关节文献委员会(International Knee Documentation Committee,IKDC)评分为17.42±11.56,关节活动范围为(27.2±19.6)°.合并内外侧半月板复合裂伤15例.通过关节镜下探查清理关节腔周围合并损伤后,采用患者自体半腱肌股薄肌肌腱重建前交叉韧带(anterior cruciate ligament,ACL),人工韧带(ligament advanced reinforcement system,LARS),韧带重建后交叉韧带(poster cruciate ligament,PCL),并使用带线锚钉修复内侧副韧带(medial cruciate ligament,MCL).结果:患者出院后均获随访,随访时间为6～24(平均18.2)个月.术后2年Lysholm膝关节功能评分为89.23±9.23,关节活动范围116.56°±12.8°,IKDC评分为88.74±8.74,与术前评分对比差异有统计学意义(P＜0.05).结论:在膝关节脱位致多韧带损伤的治疗方案中,Ⅰ期关节镜下行ACL和PCL重建术,并使用带线锚钉修补MCL断端,患者受到的损伤小,术后膝关节的稳定性恢复佳,通过进一步的康复理疗,关节粘连发生率较低,可得到相对满意的近期疗效,此方法值得临床参考并借鉴.     

膝关节多韧带损伤一期重建后5年随访

背景：前后交叉韧带损伤合并Ⅲ度内侧副韧带损伤严重影响膝关节的稳定性,重建后短期疗效确切,但中期疗效尚不明确。 目的：评估多韧带损伤重建后的中期疗效。 方法：选择40例前后交叉韧带损伤合并Ⅲ度内侧副韧带损伤的患者,男30例,女10例,年龄19-48岁,前后交叉韧带损伤于关节镜下行同种异体肌腱重建,内侧副韧带损伤行带线铆钉修补。重建前后行Lachman试验、IKDC分级、Lysholm评分及KT-1000对患者进行主观和客观评分,以评估重建疗效。 结果与结论：40例患者均获随访,随访时间60个月。重建后患者膝关节疼痛、肿胀、屈伸活动受限等症状明显改善,Lachman试验、Lysholm膝关节功能评分、IKDC分级评分及KT-1000较重建前明显提高(P < 0.05),提示应用同种异体肌腱重建前后交叉韧带、带线铆钉修补内侧副韧带,能有效恢复膝关节的稳定性,短中期疗效确切。     

Quantitative evaluation of nutritional pathways for the posterior cruciate ligament and the lateral collateral ligament in rabbits

The cruciate ligament of the knee receives its nutrition from a direct vascular supply and by permeation of nutrients from the synovial fluid. The contributions of these two routes as nutritional pathways are not known in detail. In this study, we injected [³H]methyl glucose as a tracer intravenously or directly into the knee of rabbits. Tracer concentrations in plasma, synovial fluid, the posterior cruciate ligament (PCL), and the lateral collateral ligament (LCL) were analysed by a pharmacokinetic compartment model. The contribution of [³H]methyl glucose permeation from the synovial fluid during steady state was calculated at 44.3% in the PCL and at 39.0% in the LCL. Although these results indicated that more than half the nutrition for both ligaments is provided by its vascular supply, synovial fluid permeation is also an important transport route for small molecules for the PCL and the LCL, which is an extra-articular structure.     

创伤后膝骨关节炎发展中前交叉韧带损伤的作用与意义#br#

文题释义： 创伤后骨关节炎：又称外伤性骨关节炎、损伤性骨关节炎,它是由创伤引起的以关节软骨的退化变性和继发的关节周围骨质增生为主要病理变化,以关节疼痛、活动障碍为主要临床表现的一种疾病。任何年龄组均可发病,但以青壮年多见,多发于创伤后、承重失衡及活动负重过度的关节。 前交叉韧带损伤：一般出现在体育运动中,橄榄球、篮球、足球、滑雪等项目尤其多见。除了膝关节与他人碰撞致伤外,78%的前交叉韧带损伤为非接触性,常发生于落地、急停及暴力扭转等动作。足球运动中,移位防守以及奔跑中踢球相对危险;篮球运动中,侧跳转身以及单腿落地相对危险;在滑雪运动中滑雪板前端受阻时,膝关节外翻旋转,是较为典型的前交叉韧带非接触性损伤机制。 背景：前交叉韧带具有稳定膝关节、限制胫股关节在胫骨前平移和旋转的作用,大多数前交叉韧带重建患者膝关节疼痛和膝关节不稳的概率增加。创伤后膝骨关节炎是前交叉韧带损伤后的严重并发症,目前其机制尚不完全清楚。 目的：综述前交叉韧带损伤与创伤后膝骨关节炎发病因素之间的关系,从而为创伤后膝骨关节炎的治疗提供帮助。 方法：第一作者应用计算机检索PubMed数据库自建库以来至2019年10月的相关文章,英文检索词“ACL injury,traumatic knee osteoarthritis,ACL reconstruction,meniscus status,body mass index,cartilage injury,age,graft selection,time interval between injury and surgery”。共检索到123篇相关文献,66篇文献符合纳入标准。 结果与结论：①半月板状态、体质量指数、软骨损伤、年龄、移植物选择、受伤与手术之间的时间间隔这些因素会对创伤后膝骨关节炎的发展产生影响;②虽然前交叉韧带重建主要是恢复前交叉韧带断裂后的稳定性,该过程的一个长期目标是降低膝关节骨关节炎产生的风险,并维持关节长期处于健康状态;③患者前交叉韧带断裂后伴随半月板损伤需要进行半月板切除也是导致膝骨关节炎的原因,这很可能是由于关节的承受力减弱和关节运动学改变所致。 ORCID: 0000-0001-9413-439X(韩广弢) 中国组织工程研究杂志出版内容重点：人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程     

Sensory innervation of the cat knee articular capsule and cruciate ligament visualised using anterogradely transported wheat germ agglutinin–horseradish peroxidase

Wheat germ agglutinin–horseradish peroxidase conjugate (WGA–HRP) was injected into the dorsal root ganglia (L5–S1) of the cat and used as an anterograde tracer substance for intra-axonal labelling of peripheral nerve endings in joint capsule and cranial (anterior) cruciate ligament (CCL). We believed that the high specificity of WGA–HRP for neural tissue along with the high visibility of its reaction product could help resolve controversies concerning the sensory innervation of the cruciate ligaments. Substantial amounts of WGA–HRP were transported in tibial nerve axons to the level of the knee. However, using standard HRP histochemistry we found that the capsular tissue and ligament synovia disintegrated during the incubation reaction. This problem was avoided by air drying the tissue slices on glass slides prior to reaction. Abundant labelling occurred in the posterior capsule with dense filling of axons and terminal endings. Sensory endings displayed features consistent with Ruffini endings and pacinian corpuscles. Sensory endings were located throughout the CCL in its sagittal plane, in the subsynovial layers and between collagen fascicles. In each CCL we observed 5–17 ovoid and elongated endings with dense terminal arborisations. These endings were between 100 and 150 μm long, were encapsulated, and gave rise to 1 or 2 axons. Large (up to 1.5 mm in maximum extent) elongated regions of dense, inhomogeneous labelling were found in the body of several CCLs. These resembled Golgi tendon-like endings, with the exception of their large size. We conclude that anterograde transport of HRP to the knee is a useful technique for labelling mechanoreceptors and axons in knee tissue. However, recently developed immunohistochemical analysis of peripheral tissue using protein gene product 9.5 appears to be the method of choice and should be employed for further study of human and animal cruciate ligament innervation.     

Retain or sacrifice the posterior cruciate ligament in total knee arthroplasty? A histopathological study of the cruciate ligament in osteoarthritic and rheumatoid disease

BACKGROUND: The decision whether to retain or resect the posterior cruciate ligament in total knee arthroplasty is at present determined clinically by preoperative radiological variables focusing upon the amount of joint destruction, and subsequent soft tissue contractures. However, these variables give only indirect information on the histological integrity and proprioceptive properties of the posterior cruciate ligament. METHODS: Twenty posterior cruciate ligaments, obtained during total knee arthroplasty, were evaluated histologically to study the relation between the degree of preoperative radiological joint destruction, structural integrity of the posterior cruciate ligament and the neurological integrity of the targeted tissue. Eleven patients had osteoarthritis and nine patients rheumatoid arthritis. Haematoxylin and eosin, Alcian blue (mucoid degeneration), elastica von Gieson, Gomori (elastic fibres and collagen), and immunohistochemical staining for neural structures were used. RESULTS: In all but one of the posterior cruciate ligaments, morphologically intact neural tissue was present in the peritendineum of the ligaments. Structural integrity of the collagen framework was present in only seven posterior cruciate ligaments. These cases all had grade three or four radiological joint destruction. In 13 of the specimens a certain degree of mucoid degeneration of collagen was present. All patients with grade five radiological knee joint destruction displayed mucoid degeneration and irregularity of the posterior cruciate ligament fibres. CONCLUSION: Because of the extensive architectural and probably functional damage of the posterior cruciate ligament in patients who have grade five radiological knee joint destruction, retention of the posterior cruciate ligament in knee prosthesis should not be advocated.     

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。     

Ultrastructural and Morphological Characteristics of Human Anterior Cruciate Ligament and Hamstring Tendons

Hamstring tendons are a commonly used substitute for anterior cruciate ligament (ACL) reconstruction. Ligaments and tendons are similar in composition but the ACL is more complex than hamstring tendons in function and gross morphology, which are highly dependent on its structure and ultrastructure. The purpose of this study was to compare the morphology and ultrastructure of normal human ACL and hamstring tendons, including the cell type and arrangement, expression level of proteoglycans, diameter, and density of collagen fibrils. Twenty semitendinosus or gracilis tendons and 20 ACL specimens were harvested from patients with ACL rupture or osteoarthritis undergoing routine total knee arthroplasty. The specimens were examined histologically and the ultrastructure was observed using scanning and transmission electron microscopy. Semitendinosus and gracilis tendons showed a homogeneous arrangement of collagen fibers and cell type. They had lower fibril density and more widely distributed fibril diameters. In the ACL, there was a more complex arrangement of collagen fibers, distribution of proteoglycans and different cell types. Electronic microscopy demonstrated a combination of parallel, helical and nonlinear networks of ACL fibrils, and fibril diameters were smaller and more nonuniform. This study compared the anatomy of normal human ACL and hamstring tendons, which may provide a standard for evaluating hamstring tendons grafts after ACL reconstruction and may facilitate the application of hamstring tendons in clinical applications. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.     

高屈曲状态下膝关节静力稳定结构的生物力学研究进展

膝关节高屈曲状态在亚洲国家和中东地区的日常生活及特殊职业中极为常见。膝关节静力稳定结构包括前、后交叉韧带,内、外侧副韧带及关节囊,其主要功能是维持关节稳定性,其生物力学和运动学特点对全膝置换术中软组织松解、膝关节韧带重建及损伤后的康复具有重要意义。本文对近年来膝关节生物力学的研究方法及静力稳定结构在膝关节由伸直到高屈曲运动过程中的生物力学特点进行了阐述;对今后全膝置换术中软组织平衡、膝关节韧带修复与重建及伤后与术后康复方面的研究方向进行了展望和预测。     

膝关节脱位合并多发韧带损伤的治疗策略及疗效分析

目的 探讨膝关节脱位合并多发韧带损伤的治疗策略及临床疗效。方法 回顾性分析2010年3月—2014年5月芜湖市中医院关节二科收治的16例膝关节脱位合并多发韧带损伤患者的临床资料,其中男11例,女5例;年龄22~68岁,平均36.5岁。根据改良Schenck膝关节脱位分型方法,KD-Ⅰ型1例,KD-Ⅱ 2例,KD-ⅢM型6例,KD-ⅢL型2例,KD-Ⅳ型3例,KD-Ⅴ型2例。合并前交叉韧带损伤16例,后交叉韧带损伤15例,内侧副韧带损伤11例,外侧副韧带损伤7例,后外侧复合体损伤2例,后内侧复合体损伤3例。所有患者在入院后3周内在关节镜下进行一期小切口韧带修复重建术。观察末次随访时膝关节稳定性,术前和末次随访时国际膝关节文献记录委员会(IKDC)评分、Lysholm膝关节功能评分和膝关节活动度评分,应用配对t检验进行统计学分析。结果 16例患者中,术中发生腘动脉损伤1例,术后发生胫骨侧骨隧道切口愈合不良2例、感染2例,均予相应处理后痊愈。术后第3天所有患者摄X线片示关节对合良好,重建骨隧道位置良好,内固定牢靠。16例患者随访12～48个月,平均28个月。末次随访时,X线片示重建骨隧道均无明显扩大及内固定松动,无一例韧带翻修。末次随访时膝关节屈曲115°～135°,平均124°;IKDC评分(89.64±3.15 )分、Lysholm膝关节功能评分(82.88±6.57)分和膝关节活动度123.56°±5.20°,与术前比较差异均有统计学意义(t=57.791、71.563、25.998,P值均＜0.01)。根据IKDC评分、Lysholm膝关节评分评价,膝关节功能优9例、良4例、可2例、差1例。结论 膝关节脱位合并多发韧带损伤是一类严重复杂的损伤,需系统地评估患者病情,根据患者损伤的程度制定个性化的治疗方案,在关节镜下行一期韧带重建或修复术,可获得良好的临床疗效,降低致残率。     

Development of the human knee joint ligaments

ABSTRACT Background: Many studies have been published on the development of the human knee joint, but scant attention has been given to the development of the knee joint ligaments. The only elements that have received much attention are the cruciate ligaments and their relationships with the synovial membrane. Methods: We summarize our observations on the development of the knee joint ligaments in 50 serially sectioned human embryonic and fetal lower limbs (26 embryos and 24 fetuses). Results: The patellar ligament begins to form in O'Rahilly stage 20, with the muscle fibers of the quadriceps muscle being attached inferiorly to the tibial tuberosity. The cruciate ligaments (beginning with the posterior) arise from the articular interzone in O'Rahilly stage 21. Subsequently, with the organization of the Wrisberg's meniscofemoral ligament, in week 10 of development, the cruciate ligament system is completed. The lateral collateral ligament begins to form in O'Rahilly stage 23, and from its first appearance it is independent of the knee joint capsule. At this time, development of the tendon of the popliteus muscle begins. The medial collateral ligament begins to develop in week 9 of development as a condensation of the joint capsule. Two weeks later, the intra-articular pad of fat begins to form from mesenchymal tissue below the patella and between the cruciate and the patellar ligaments. With the organization of the suprapatellar bursa in week 14 of development, knee joint development is complete. Conclusions: The morphogenetic time table of the knee joint ligaments was established. Anat. Rec. 248:259-268, 1997. © 1997 Wiley-Liss, Inc.     

Vascular volume determination of articular tissues in normal and anterior cruciate ligament-deficient rabbit knees

The vasculature of diarthroidal joints has been well documented; however, the volume of vessels supplying different articular tissues is unknown. Angiogenesis, the formation of new vessels from preexisting ones, is difficult to quantify in joints due to the unavailability of a suitable technique. Although angiogenesis is known to occur in rheumatoid arthritis, the development of new vessels following joint injury has not been ascertained. A vascular casting technique was developed using carmine red dye to measure the vascular volume of the medial collateral ligament (MCL), lateral collateral ligament (LCL), menisci, medial capsule, and infrapatellar fat pad of the rabbit knee joint. Vascular volume determinations were repeated at 4 weeks in a group of anterior cruciate ligament (ACL)-transected animals and in a sham-operated control group. The volume of vessels supplying the MCL was estimated to be 0.22 ± 0.07 μl (mean ± S.E.M.), the LCL volume was 0.25 ± 0.05 μl, the medial meniscus volume was 0.19 ± 0.03 μl, the lateral meniscus volume was 0.40 ± 0.08 μl, the medial capsule volume was 0.14 ± 0.05 μl, and the infrapatellar fat pad volume was 1.90 ± 0.62 μl. Following ACL transection, angiogenesis was found to occur in the MCL only. All other tissue vascularities were not significantly different from sham-operated controls. A quantifiable method for measuring vascular volume of knee joint tissues has been described. Joint instability stimulates angiogenesis in the ipsilateral MCL; however, the absence of angiogenic activity in other articular tissues might help explain the lack of posttraumatic healing associated with these joints. Anat. Rec. 251:207–213, 1998. © 1998 Wiley-Liss, Inc.     

Lateral epicondylar femoral avulsion fracture combined with tibial fracture: a counterpart to the arcuate sign

We present a case of femoral avulsion of the lateral collateral ligament (LCL) with complete tear of the posterior cruciate ligament (PCL) and popliteus tendon accompanied by demonstrable posterolateral rotary instability (PLRI) of the knee. A 55-year-old man was involved in a road traffic accident. Radiographs revealed an avulsion fracture of the lateral epicondyle of the femur and a fracture of the tibial shaft. An MRI scan showed the lateral epicondyle was avulsed by the LCL and the popliteus tendon. The PCL signal was absent. The tibial shaft fracture was fixed with an intra medullary nail. Sagging of the tibia, with loss of prominence of tibial tuberosity and a positive posterior drawer test, demonstrated a complete tear of the PCL. The avulsion fracture of the lateral epicondyle was treated by an open reduction and internal fixation with two staples. A ligament can be avulsed at either end, and to our knowledge, this pattern of injury as a counterpart to arcuate sign has never been documented in the literature. It is important not to dismiss a small avulsion fracture around the knee joint as insignificant, as it could indicate the presence of a major ligamentous injury.