Knee Joints (knee + joint)

Distribution by Scientific Domains

Kinds of Knee Joints

  • rat knee joint

  • Selected Abstracts

    Chondroprotective role of the osmotically sensitive ion channel transient receptor potential vanilloid 4: Age- and sex-dependent progression of osteoarthritis in Trpv4 -deficient mice

    ARTHRITIS & RHEUMATISM, Issue 10 2010
    Andrea L. Clark
    Objective Mechanical loading significantly influences the physiology and pathology of articular cartilage, although the mechanisms of mechanical signal transduction are not fully understood. Transient receptor potential vanilloid 4 (TRPV4) is a Ca++ -permeable ion channel that is highly expressed by articular chondrocytes and can be gated by osmotic and mechanical stimuli. The goal of this study was to determine the role of Trpv4 in the structure of the mouse knee joint and to determine whether Trpv4,/, mice exhibit altered Ca++ signaling in response to osmotic challenge. Methods Knee joints of Trpv4,/, mice were examined histologically and by microfocal computed tomography for osteoarthritic changes and bone structure at ages 4, 6, 9, and 12 months. Fluorescence imaging was used to quantify chondrocytic Ca++ signaling within intact femoral cartilage in response to osmotic stimuli. Results Deletion of Trpv4 resulted in severe osteoarthritic changes, including cartilage fibrillation, eburnation, and loss of proteoglycans, that were dependent on age and male sex. Subchondral bone volume and calcified meniscal volume were greatly increased, again in male mice. Chondrocytes from Trpv4+/+ mice demonstrated significant Ca++ responses to hypo-osmotic stress but not to hyperosmotic stress. The response to hypo-osmotic stress or to the TRPV4 agonist 4,-phorbol 12,13-didecanoate was eliminated in Trpv4,/, mice. Conclusion Deletion of Trpv4 leads to a lack of osmotically induced Ca++ signaling in articular chondrocytes, accompanied by progressive, sex-dependent increases in bone density and osteoarthritic joint degeneration. These findings suggest a critical role for TRPV4-mediated Ca++ signaling in the maintenance of joint health and normal skeletal structure. [source]

    Attenuation of osteoarthritis progression by reduction of discoidin domain receptor 2 in mice

    ARTHRITIS & RHEUMATISM, Issue 9 2010
    Lin Xu
    Objective To investigate whether the reduction of discoidin domain receptor 2 (DDR-2), a cell membrane tyrosine kinase receptor for native type II collagen, attenuates the progression of articular cartilage degeneration in mouse models of osteoarthritis (OA). Methods Double-heterozygous (type XI collagen,deficient [Col11a1+/,] and Ddr2 -deficient [Ddr2+/,]) mutant mice were generated. Knee joints of Ddr2+/, mice were subjected to microsurgical destabilization of the medial meniscus. Conditions of the articular cartilage from the knee joints of the double-heterozygous mutant and surgically treated mice were examined by histology, evaluated using a modified Mankin scoring system, and characterized by immunohistochemistry. Results The rate of progressive degeneration in knee joints was dramatically reduced in the double-heterozygous mutant mice compared with that in the type XI collagen,deficient mice. The progression in the double-heterozygous mutant mice was delayed by ,6 months. Following surgical destabilization of the medial meniscus, the progressive degeneration toward OA was dramatically delayed in the Ddr2+/, mice compared with that in their wild-type littermates. The articular cartilage damage present in the knee joints of the mice was directly correlated with the expression profiles of DDR-2 and matrix metalloproteinase 13. Conclusion Reduction of DDR-2 expression attenuates the articular cartilage degeneration of knee joints induced either by type XI collagen deficiency or by surgical destabilization of the medial meniscus. [source]

    Different amplifying mechanisms of interleukin-17 and interferon-, in Fc, receptor,mediated cartilage destruction in murine immune complex,mediated arthritis

    ARTHRITIS & RHEUMATISM, Issue 2 2009
    Lilyanne C. Grevers
    Objective Previously, we reported that interferon-, (IFN,) aggravates cartilage destruction in immune complex (IC),mediated arthritis via up-regulation of activating Fc, receptors (Fc,R). Recently, we found that interleukin-17 (IL-17) also aggravates cartilage destruction in arthritis models in which ICs are involved, but the underlying mechanism remains unknown. This study was undertaken to determine the role of IL-17 in Fc,R-mediated cartilage destruction in IC-mediated arthritis and to compare its effect with that of IFN,. Methods IC-mediated arthritis was passively induced in ,-chain,/, mice, which lack functional activating Fc,R, and in wild-type controls. AdIL-17 or a control vector was injected into the knee joints 1 day prior to induction of IC-mediated arthritis. Knee joints were isolated for histologic analysis, and synovium samples were obtained for reverse transcriptase,polymerase chain reaction (RT-PCR). Macrophage (RAW 264.7) cell lines and polymorphonuclear cell (PMN; 32Dcl3) lines were stimulated with IFN, or IL-17 for analysis of Fc,R expression using RT-PCR and fluorescence-activated cell sorting. Results IL-17 overexpression prior to induction of IC-mediated arthritis significantly aggravated cartilage destruction and inflammation, characterized by a massive influx of PMNs, which adhered to the cartilage surface. Although IL-17 overexpression increased Fc,R messenger RNA levels in the synovium, in vitro stimulation of macrophages and PMNs revealed that, in contrast to IFN,, IL-17 did not directly regulate Fc,R expression. Despite similar inflammation in AdIL-17,enhanced IC-mediated arthritis in ,-chain,/, mice and wild-type controls, severe cartilage destruction and PMN adherence were completely absent in ,-chain,/, mice. Conclusion Our findings indicate that IL-17,mediated aggravation of cartilage destruction in IC-mediated arthritis is Fc,R dependent. However, in contrast to IFN,, which directly up-regulates Fc,R expression on macrophages and PMNs, IL-17 enhances cartilage destruction by increasing the local amount of Fc,R-bearing neutrophils. [source]

    Successful angiographic embolization of recurrent elbow and knee joint bleeds in seven patients with severe haemophilia

    HAEMOPHILIA, Issue 1 2009
    Summary., In haemophilic joints with high-grade arthropathy, bleeds occur that do not respond to replacement therapy of the deficient coagulation factor. The reason may be pathologically reactive angiogenesis in chronic synovitis. Seven patients with severe haemophilia A or haemophilia B experienced recurrent massive bleeds of one elbow joint or knee joint in the absence of trauma. After initial application of factor VIII or IX (fVIII/fIX; 50 IU kg,1 bodyweight), there was only slow and never complete relief of symptoms. Despite intensive secondary prophylaxis maintaining the plasma level of factor concentrate at minimum 50%, new massive bleeds at the same location occurred. Vascular bleeding was suspected. Angiography of the arteries was performed via the femoral artery. Vessels identified as potential bleeding sources were embolized with embolization fluid (ONYX) in eight joints (six elbow and two knee joints). Under low-dose prophylactic treatment (15 IU fVIII or fIX per kg bodyweight for three times per week), no recurrent severe bleed unresponsive to coagulation factor replacement occurred after a mean observation time of 16 months after embolization. The consumption of factor concentrate decreased to one-third of the amount consumed before embolization. In conclusion, angiographic embolization with a non-adhesive liquid embolic agent might be considered as a promising therapeutic and coagulation factor saving option in joint bleeds not responding to replacement of coagulation factor to normal levels. [source]

    Radiation synovectomy by 188Re-Sulfide in haemophilic synovitis

    HAEMOPHILIA, Issue 5 2004
    P. Li
    Summary., Radiation synovectomy is a safe and effective treatment for chronic haemophilic synovitis causing recurrent haemarthroses. This study reports results of 29 188Re-sulfide radiation synovectomies in knee joint with a follow-up 18 months. Using the absorbed dose factor, three groups of radioactivity dose (555 MBq, 687 MBq and 917 MBq) were used according to the synovium thickness that measured by MRI. Excellent and good results (haemarthrosis reduction from 75 to 100%) were obtained in 71% of cases at 18 months. Comparison of the results, no significant difference was found among the radioactivity dose groups. Radiation was well contained within the knee. There were no observed or identified complications including the detectable harm to the articular cartilage, as shown by MRI. [source]

    Experimental haemophilic synovitis: rationale and development of a murine model of human factor VIII deficiency

    HAEMOPHILIA, Issue 3 2004
    L. A. Valentino
    Summary., Haemophilia is a genetic disease as a result of the deficiency of blood coagulation factor VIII or IX. Bleeding is common, especially into joints where an inflammatory, proliferative synovitis develops resulting in a debilitating arthritis, haemophilic arthropathy. The pathogenesis of blood-induced haemophilic synovitis (HS) is poorly understood. The gross, microscopic and ultrastructural changes that occur in the synovial membrane following human and experimental hemarthrosis have been described. Repeated episodes of bleeding induce synoviocyte hypertrophy and hyperplasia, an intense neovascular response and inflammation of the synovial membrane. The component(s) in blood that initiates these changes is(are) not known, although iron is often proposed as one possibility. Here, we describe a novel murine model of human haemophilia A, which facilitates the examination of large number of animals and tissue specimens. The effects of hemarthrosis on the physical, gross and microscopic changes evoked following joint bleeding are described. Controlled, blunt trauma to the knee joint consistently resulted in joint swelling because of a combination of bleeding and inflammation. Hemosiderin was found in the synovial membrane. Similar to hemarthrosis in human haemophilia, joint bleeding resulted in acute morbidity evidenced by inactivity, weight loss and immobility. With time the animals recovered. The model of experimental murine HS described here has utility in the study of the pathogenesis of HS. This is the first of a series of articles, which will discuss the pathophysiology and characterize the model, with comparison of his model to others which have been published previously. It should provide a useful model to test potential therapeutic interventions. [source]

    Morphological changes in the shape of the non-pathological bony knee joint with age: a morphometric analysis of the distal femur and proximal tibia in three populations of known age at death

    S. D. Stevens
    Abstract This study examines possible morphological variation in the knee joint of Homo sapiens with increasing age in ostensively healthy and non-pathological distal femora and proximal tibiae. Throughout the lifetime of each individual, the hard tissue of the knee undergoes considerable remodelling as a response to biomechanical stresses, changes in bone microarchitecture and reduction of bone mineral content as a concomitant of ageing. The knee is also subject to greater levels of degenerative joint disease than any other joint. If death occurs whilst such diseases are in the earliest stages, initial bone changes may not be visually obvious in museum specimens. If such specimens are used for comparative analyses, it is hypothesised that changes might render it problematic if all ages are conglomerated into discrete samples. This study therefore investigates the degree to which the distal femur and proximal tibia change shape during ageing and, if changes are present, whether they are expressed similarly in males and females. It also examines whether changes are of greater magnitude than those morphological differences which might exist between populations. In an example population of African-Americans, results indicate that there is a statistically significant difference in shape between age groups and those differences become progressively greater between the youngest and oldest adults. Results also show that although morphological variation caused by ageing is apparent, those shape differences attributable to sexual dimorphism are more powerful. When two additional populations are analysed jointly with the African-Americans (Caucasian Americans and the European Spitalfields sample), results indicate that inter-population shape differences are considerably greater than differences caused by increasing age. Results imply that it is justifiable to combine specimens of all ages into discrete samples for comparative purposes. Copyright 2007 John Wiley & Sons, Ltd. [source]

    A method to establish the relationship between chronological age and stage of union from radiographic assessment of epiphyseal fusion at the knee: an Irish population study

    JOURNAL OF ANATOMY, Issue 2 2008
    J. E. O'Connor
    Abstract Characteristic changes during epiphyseal union provide a skeletal age, which when compared with age-based standards provides an estimation of chronological age. Currently there are no data on epiphyseal union for the purposes of age estimation specific to an Irish population. This cross-sectional study aims to investigate the relationship between stage of epiphyseal union at the knee joint and chronological age in a modern Irish population. A novel radiographic method that sub-divides the continuum of development into five specific stages of union is presented. Anteroposterior and lateral knee radiographs of 148 males and 86 females, aged 9,19 years, were examined. Fusion was scored as Stage 0, non-union; Stage 1, beginning union; Stage 2, active union; Stage 3, recent union; or Stage 4, complete union. Stage of epiphyseal union is correlated with chronological age in both males and females. Mean age gradually increases with each stage of union and also varies between male and female subjects. A statistically significant difference in mean age was recorded between stages when compared to the previous stage, for the three epiphyses. Irish children are comparable to those from previously published studies with epiphyseal union in females occurring earlier than males. A significant difference was noted between the mean age of union for males and females for each of Stages 1 and 2 for the femur and Stages 0, 1, 2 and 3 for the tibia and the fibula. The results also suggest that the stages of union occur at earlier ages in this Irish population. Implementation of standardized methodology is necessary to investigate if this is due to a secular or population variation in maturation or to a methodology which clearly identifies five stages of union. [source]

    Ultrasonographic assessment of Baker's cysts after intra-articular corticosteroid injection in knee osteoarthritis

    J. Carlos Acebes MD
    Abstract Purpose: To assess sonographic changes in Baker's cysts (BCs) of patients with knee osteoarthritis after a single intra-articular corticosteroid injection. Methods: Thirty patients with knee osteoarthritis complicated with a symptomatic BC received a single intra-articular injection of 40 mg triamcinolone acetonide. Knee pain, swelling, and range of motion were evaluated. BC area and thickness of the cyst wall were measured with sonography before and 4 weeks after local treatment. Results: A significant improvement in knee pain, swelling, and range of motion after corticosteroid injection was accompanied by a decrease in size of the BCs as well as in thickness of the cyst wall as measured by sonography. Moreover, the reduction of BC area on sagittal scans after treatment was significantly correlated with the improvement in range of motion. Conclusions: In this series of osteoarthritis patients, injection of corticosteroids inside the knee joint accounted for a reduction in BC dimensions as well as cyst wall thickness. Sonography can be used not only for the diagnosis of BCs but also to monitor response to therapy. 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:113,117, 2006 [source]

    Iliotibial band thickness: Sonographic measurements in asymptomatic volunteers

    Lesley-Ann Goh FRCR
    Abstract Purpose. The aims of this study were to measure the thickness of the iliotibial band (ITB) in asymptomatic adult volunteers and to determine whether there was any correlation between these measurements and the subjects' age, weight, or height. Methods. Sonography was used to measure the ITB thickness in 31 asymptomatic volunteers (13 men and 18 women) ranging from 25 to 68 years old. Two radiologists obtained the sonographic measurements of each volunteer at the levels of the femoral condyle and the tibial condyle of both knees. Findings of fluid or bursae adjacent to the ITB were recorded. Results. The mean ITB thickness was 1.95 mm 0.3 mm ( standard deviation) at the level of the femoral condyle and 3.4 mm 0.5 mm at the level of the tibial condyle. There was a statistically significant negative correlation between ITB thickness and subject age. There was no significant correlation between ITB thickness and subject weight or height. Joint fluid was present in the lateral recess of both knees in 29 volunteers (93.5%) and 1 knee joint in 2 volunteers (6.5%). Bursae were present in 3 volunteers (9.7%). Conclusions. The mean sonographic values of normal ITB thickness established using sonography may be helpful in diagnosing ITB pathology. There is no significant correlation between ITB thickness and subject weight or height, but there is a negative correlation between ITB thickness and subject age. Joint fluid in the lateral recess is present in most asymptomatic individuals, but bursae are rare. 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:239,244, 2003 [source]

    Real-time MRI of joint movement with trueFISP

    Harald H. Quick MSc
    Abstract Purpose To develop a technique for dynamic magnetic resonance imaging (MRI) of joint motion based on a combination of real-time TrueFISP (fast imaging with steady state precession) imaging with surface radiofrequency (RF) coils. Materials and Methods The metacarpal, elbow, tarsal, and knee joint of five volunteers and the knees of four patients were examined with a real-time TrueFISP sequence during movement of the joints. Results All examined joints could be assessed under dynamic conditions with high image contrast and high temporal resolution. Conclusion Dynamic MRI of joints with TrueFISP is feasible and can provide information supplemental to static joint examinations. J. Magn. Reson. Imaging 2002;15:710,715. 2002 Wiley-Liss, Inc. [source]

    Acute arthritis as an unusual complication of malignancy

    Yvonne Zissiadis
    SUMMARY A 59-year-old man presented with an inability to weight-bear due to an acute, red, hot, swollen knee joint which was subsequently found to be due to a malignant joint effusion consequent to colonic carcinoma. Treatment with radiation therapy relieved his symptoms. A review of the literature reveals that malignant joint effusion is rare and this is only the third reported case secondary to colonic carcinoma. [source]

    Low-intensity pulsed ultrasound (LIPUS) increases the articular cartilage type II collagen in a rat osteoarthritis model

    Kiyohito Naito
    Abstract In this study, the effect of low-intensity pulsed ultrasound (LIPUS) on cartilage was evaluated in a rat osteoarthritis (OA) model using serum biomarkers such as CTX-II (type II collagen degradation) and CPII (type II collagen synthesis) as well as histological criteria (Mankin score and immunohistochemical type II collagen staining). OA was surgically induced in the knee joint of rats by anterior cruciate/medial collateral ligament transection and medial meniscus resection (ACLT,+,MMx). Animals were divided into three groups: sham-operated group (Sham), ACLT,+,MMx group without LIPUS (,LIPUS), and ACLT,+,MMx group with LIPUS (+LIPUS; 30 mW/cm2, 20 min/day for 28 days). CTX-II levels were elevated in both ,LIPUS and +LIPUS groups compared to that in the Sham group after the operation, but there was no significant difference between +LIPUS and ,LIPUS groups, suggesting that LIPUS does not affect the degradation of type II collagen in this model. In contrast, CPII was significantly increased in +LIPUS group compared to ,LIPUS and Sham. Moreover, histological damage on the cartilage (Mankin score) was ameliorated by LIPUS, and type II collagen was immunohistochemically increased by LIPUS in the cartilage of an OA model. Of interest, mRNA expression of type II collagen was enhanced by LIPUS in chondrocytes. Together these observations suggest that LIPUS is likely to increase the type II collagen synthesis in articular cartilage, possibly via the activation of chondrocytes and induction of type II collagen mRNA expression, thereby exhibiting chondroprotective action in a rat OA model. 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:361,369, 2010 [source]

    Changes of articular cartilage after immobilization in a rat knee contracture model

    Yoshihiro Hagiwara
    Abstract The objective was to determine the changes of articular cartilage of the knee joint during immobilization in a rat model. The knee joints of adult male rats were immobilized at 150 of flexion using an internal fixator for 3 days, and 1, 2, 4, 8, and 16 weeks. The articular cartilage from the medial midcondylar region of the knee was obtained, divided into three areas (non-contact area, transitional area, contact area), and in each area, a degree of degeneration was evaluated by gross observation, histomorphometric grading, and measurements of thickness and number of chondrocytes. Elasticity of the articular cartilage was estimated by measuring the sound speed with use of scanning acoustic microscopy. Degeneration of the articular cartilage was mainly observed in the contact and transitional areas. Matrix staining intensity by safranin-O and number of chondrocytes were decreased in these two areas. The thickness of the articular cartilage in the non-contact and contact areas was unchanged, but it was increased in the transitional area. Decrease in sound speed was observed in the transitional area of both the femoral and tibial cartilage, indicating the softening of the articular cartilage. The changes of articular cartilage became obvious as early as 1 week after immobilization. These changes may be due to a lack of mechanical stress or a lack of joint fluid circulation during immobilization. Although we do not know the reversibility of these changes of articular cartilage, early mobilization is preferable to avoid these cartilage changes. 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:236,242, 2009 [source]

    Joint capsule mast cells and neuropeptides are increased within four weeks of injury and remain elevated in chronic stages of posttraumatic contractures

    Kevin A. Hildebrand
    Abstract The purpose of this article was to determine mast cell and neuropeptide nerve fiber numbers in joint capsules in posttraumatic contractures, as elevated numbers have been implicated in other fibrotic and contracture conditions. Twelve skeletally mature rabbits had intraarticular cortical windows removed from the medial and lateral femoral condyles and the knee joint immobilized. The contralateral unoperated limb served as a control. Equal numbers of rabbits were sacrificed 4 weeks after surgery or 40 weeks after the first surgery that included 32 weeks of remobilization. Six patients with chronic posttraumatic elbow joint contractures and six age-matched organ donor controls free of elbow contractures were also studied. Joint capsule myofibroblast, mast cell, and neuropeptide containing nerve fiber numbers were assessed with immunohistochemistry. The numbers of myofibroblasts, mast cells, and neuropeptide containing nerve fibers expressed as a percentage of total cells were significantly greater in the contracture capsules when compared to the control capsules at all time points (p,<,0.0001). The range of percentages for the three components in the contracture capsules versus the controls were 41,48% versus 9,10%, 44,50% versus 11,13%, and 45,50% versus 10,12% for the acute and chronic stages of the rabbit model and the chronic stages in the human elbows, respectively. These data support the hypothesis that a myofibroblast,mast cell,neuropeptide fibrosis axis may underlie some of the pathologic changes in the joint capsule in posttraumatic contractures. Approaches designed to manipulate this axis, such as preventing degranulation of mast cells, warrant further investigation. 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1313,1319, 2008 [source]

    Patellar blood flow during knee arthroplasty surgical exposure: Intraoperative monitoring by laser doppler flowmetry

    Axel Hempfing
    Abstract Patellofemoral complications following knee arthroplasty are a well-known problem. Patellar ischemia has been suspected to be causative for fracture, anterior knee pain, and patella component failure. The purpose of this study was to assess the influence of knee arthroplasty surgical dissection on patellar blood flow. Patellar blood flow was measured by means of intraosseous laser Doppler flowmetry (LDF) in 10 patients undergoing total knee arthroplasty by a standard medial parapatellar approach. The initial blood flow was 121.6,,114.7 AU. The signal significantly decreased by 71% (p,=,0.0051) when the knee was flexed and lost the pulsatile signal pattern in 80%. After arthrotomy, the signal was 100.1,,120.3 AU in extension. The lowest signal was found in flexion and eversion of the patella (mean, 18,,10.7 AU) and all signals lost pulsatility. As compared to the initial values, completion of the soft tissue dissection did not lead to a significant change of the blood flow signal (121.3,,104.8; p,=,0.6835). Flexion of the knee joint markedly reduced patellar perfusion. Standard medial parapatellar approach did not significantly change patellar blood flow. This study does not support the theory of postoperative patellar ischemia as a cause of anterior knee pain or patellofemoral problems. 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1389,1394, 2007 [source]

    Joint degeneration following closed intraarticular fracture in the mouse knee: A model of posttraumatic arthritis

    Bridgette D. Furman
    Abstract Posttraumatic arthritis is one of the most frequent causes of disability following joint trauma. The objective of this study was to develop a model of a closed articular fracture in the mouse knee joint to quantify the temporal sequence of joint degeneration in a model of posttraumatic arthritis. Closed intraarticular fractures were created in the tibial plateau of adult mice (C57BL/6) using a computer-controlled materials testing system and a custom-built indenter tip. Tibial plateau fractures were classified and imaged over time using high-resolution digital radiography. Animals were sacrificed at 2, 4, 8, and 50 weeks following fracture, and the experimental and contralateral control limbs were harvested for histology and micro-computed tomography (microCT) analysis. By radiographic analysis, tibial plateau fractures closely resembled clinical fractures. More complex and comminuted fractures correlated to significantly higher fracture energies. Histologic analysis demonstrated progressive joint degeneration as measured by a modified Mankin scale, with fibrillation and loss of proteoglycan in the articular cartilage. Subchondral bone thickening was also observed in experimental joints. The induction of a closed intraarticular fracture of the mouse tibial plateau generated a reproducible and clinically relevant joint injury that progressed to osteoarthritis-like changes by histologic and microCT evaluations. The ability to induce joint degeneration without an osteotomy or open arthrotomy provides a valuable new model for studying the natural sequelae of posttraumatic arthritis. Notably, the use of a murine model will facilitate the use of genetically modified animals for the investigation of specific genes implicated in the pathology of posttraumatic arthritis. 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:578,592, 2007 [source]

    The role of M. popliteus in unpredictable and in self-initiated balance provocations

    Ann-Katrin Stensdotter
    Abstract The purpose of this study was to determine whether m. popliteus (POP) activity would contribute to the control of knee joint position in unpredictable and in self-initiated provocations of standing balance. Ten healthy women (age 25.2,,4.5 years, means and SD) without known knee pathology were tested for postural reactions (1) to unpredictable support surface translations in anterior and posterior directions, and (2) in self-initiated balance provocations in a reaction time (RT) forward reach-and-grip task. Electromyographic activity was recorded from POP and other leg muscles plus the deltoid muscle. Three-dimensional kinematics were captured for the knee joint and the body centre of mass was calculated. POP was active first of all the muscles recorded, regardless of translation direction, and knee joint movements elicited were either knee extension or external rotation of the tibia. In the RT task, the POP was active after initiation of reaching movement, and there was little consistency in the kinematic response. POP activity was not direction specific in response to support surface translation, but appeared triggered from reactive knee joint movement. The response to the support-surface translation suggests that POP served to control knee joint position rather than posture. In the RT task, we could not deduce whether POP activity was attributed to knee joint control or to postural control. 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 24:524,530, 2006 [source]

    Detection of changes in articular cartilage proteoglycan by T1, magnetic resonance imaging

    Andrew J. Wheaton
    Abstract The purpose of this work is to demonstrate the feasibility of T1, -weighted magnetic resonance imaging (MRI) to quantitatively measure changes in proteoglycan content in cartilage. The T1, MRI technique was implemented in an in vivo porcine animal model with rapidly induced cytokine-mediated cartilage degeneration. Six pigs were given an intra-articular injection of recombinant porcine interleukin-1, (IL-1,) into the knee joint before imaging to induce changes in cartilage via matrix metalloproteinase (MMP) induction. The induction of MMPs by IL-1 was used since it has been extensively studied in many systems and is known to create conditions that mimic in part characteristics similar to those of osteoarthritis. The contralateral knee joint was given a saline injection to serve as an internal control. T1, -weighted MRI was performed on a 4 T whole-body clinical scanner employing a 2D fast spin-echo-based T1, imaging sequence. T1, relaxation parameter maps were computed from the T1, -weighted image series. The average T1, relaxation rate, R1, (1/T1,) of the IL-1,-treated patellae was measured to be on average 25% lower than that of saline-injected patellae indicating a loss of proteoglycan. There was an average reduction of 49% in fixed charge density, measured via sodium MRI, of the IL-1,-treated patellae relative to control corroborating the loss of proteoglycan. The effects of IL-1,, primarily loss of PG, were confirmed by histological and immunochemical findings. The results from this study demonstrate that R1, is able to track proteoglycan content in vivo. 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source]

    Expression of the CD44 variant isoform 5 in the human osteoarthritic knee joint: Correlation with radiological, histomorphological, and biochemical parameters

    Susanne Fuchs
    Abstract Purpose: The purpose of this study was to correlate expression of CD44v5 in osteoarthritic synovium, cartilage, and synovial fluid with radiographical, histomorphological, and biochemical data. Methods: Cartilage and synovia specimens of 27 patients with osteoarthritis were histomorphologically assessed according to Mankin and Pelletier, respectively. Extended weight-bearing antero-posterior radiographs were evaluated according to Kellgren and Ahlback. Expression of membrane-bound CD44v5 was analyzed by immunohistochemistry and levels of soluble CD44v5 were determined by ELISA. Results: Expression of CD44v5 in cartilage and synovia was detected in 67% and 59% of the patients, respectively. Immunohistochemical findings in cartilage correlated significantly with structural cartilage changes (p < 0.001), whereas no correlation was found between expression in synovia and inflammatory synovial changes. Additionally, no relationship was evident between CD44v5 expression and radiographical data, but expression in cartilage and synovium was significantly correlated with each other (p < 0.04). Surprisingly, expression of CD44v5 in both cartilage and synovia was negatively correlated with synovial fluid levels of TNF, (p < 0.03 and p < 0.02, respectively), and no association was evident with levels of IL-1,. Conclusions: The data demonstrate expression of CD44v5 in osteoarthritic cartilage and synovia, probably independent of joint inflammation. But more importantly, expression of this receptor variant in cartilage seems to be strongly related to the degree of cartilage destruction. 2003 Published by Elsevier Ltd. on behalf of Orthopaedic Research Society. 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source]

    Tibio-femoral loading during human gait and stair climbing

    William R. Taylor
    Abstract Surgical intervention of the knee joint routinely endeavors to recreate a physiologically normal joint loading environment. The loading conditions resulting from osteotomies, fracture treatment, ligament replacements, and arthroplasties of the knee are considered to have an impact on the long term clinical outcome; however, knowledge regarding in vivo loading conditions is limited. Using a previously validated musculoskeletal lower limb model, we predicted the tibio-femoral joint contact forces that occur in the human knee during the common daily activities of walking and stair climbing. The average resultant peak force during walking was 3.1 times body weight (BW) across four total hip arthroplasty patients. Inter-individual variations proved larger than the variation of forces for each patient repeating the same task. Forces through the knee were considerably larger during stair climbing than during walking: the average resultant peak force during stair climbing was 5.4 BW although peaks of up to 6.2 BW were calculated for one particular patient. Average anteroposterior peak shear components of 0.6 BW were determined during walking and 1.3 BW during stair climbing. These results confirm both the joint contact forces reported in the literature and the importance of muscular activity in creating high forces across the joint. The magnitudes of these forces, specifically in shear, have implications for all forms of surgical intervention in the knee. The data demonstrate that high contact and shear forces are generated during weight bearing combined with knee flexion angles greater than approximately 15. Clinically, the conditions that produce these larger contact forces should be avoided during post-operative rehabilitation. 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source]

    Effects of a cultured autologous chondrocyte-seeded type II collagen scaffold on the healing of a chondral defect in a canine model

    C. R. Lee
    Using a previously established canine model for repair of articular cartilage defects, this study evaluated the 15-week healing of chondral defects (i.e., to the tidemark) implanted with an autologous articular chondrocyte-seeded type II collagen scaffold that had been cultured in vitro for four weeks prior to implantation. The amount and composition of the reparative tissue were compared to results from our prior studies using the same animal model in which the following groups were analyzed: defects implanted with autologous chondrocyte-seeded collagen scaffolds that had been cultured in vitro for approximately 12 h prior to implantation, defects implanted with autologous chondrocytes alone, and untreated defects. Chondrocytes, isolated from articular cartilage harvested from the left knee joint of six adult canines, were expanded in number in monolayer for three weeks, seeded into porous type II collagen scaffolds, cultured for an additional four weeks in vitro and then implanted into chondral defects in the trochlear groove of the right knee joints. The percentages of specific tissue types filling the defects were evaluated histomorphometrically and certain mechanical properties of the repair tissue were determined. The reparative tissue filled 88 6% (mean SEM; range 70,100%) of the cross-sectional area of the original defect, with hyaline cartilage accounting for 42 10% (range 7,67%) of defect area. These values were greater than those reported previously for untreated defects and defects implanted with a type II collagen scaffold seeded with autologous chondrocytes within 12 h prior to implantation. Most striking, was the decreased amount of fibrous tissue filling the defects in the current study, 5 5% (range 0,26%) as compared to previous treatments. Despite this improvement, indentation testing of the repair tissue formed in this study revealed that the compressive stiffness of the repair tissue was well below (20-fold lower stiffness) that of native articular cartilage. 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source]

    A novel bisphosphonate inhibits inflammatory bone resorption in a rat osteolysis model with continuous infusion of polyethylene particles

    Miho Iwase
    Abstract This study examined the inhibitory effect of a new bisphosphonate (TRK-530) on wear debris-mediated bone resorption in a rat osteolysis model involving continuous infusion of high density polyethylene (HDPE) particles. TRK-530 (TRK) is a novel synthetic bisphosphonate that has been shown to decrease the level of tumor necrosis factor alpha (TNF-,) in the bone marrow of rats with adjuvant arthritis. Forty Wistar rats were randomized to two groups (n = 20 each). In each rat, a Kirshner (K) wire was inserted into the femur and HDPE particles were continuously infused into the knee joint. Thereafter, the animals were subcutaneously injected with saline (control group) or 1 mg/kg of TRK (TRK group) every second day, and were sacrificed at 4 or 8 weeks after surgery. Radiographs obtained at the time of sacrifice were evaluated for periprosthetic osteolysis. We also examined the thickness of the reactive membrane as well as the number of osteoclast-like cells around the K-wire. In addition, we examined the expression of genes for bone-resorbing cytokines in the reactive membrane. Radiographic peri-implant osteolysis was more frequent in the control group compared with the TRK group at each time of assessment (p < 0.01). The interfacial membrane was significantly thinner in the TRK group compared with the control group (p < 0.01) and the average number of osteoclast-like cells around the K-wire was significantly fewer in the TRK group (p < 0.01). In addition, the expression of interleukin 1-alpha messenger ribonucleic acid (IL-1, mRNA) and TNF-, mRNA was suppressed in the TRK group at each time of assessment. We conclude that the TRK can inhibit the formation of inflammatory peri-implant osteolysis induced by HDPE particles. 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source]

    The effect of tibial lengthening using the Ilizarov method on the cartilage and the menisci of the knee joint

    Bernd Fink
    In order to investigate possible acute damage to the knee joint cartilage and the menisci during tibial lengthening, sixteen young beagle dogs underwent 30% lengthening of the right tibia of 2.5 cm by callus distraction at a distraction rate of twice 0.5 mm per day. A further four dogs comprised the control group with fixator and osteotomy but without lengthening. After a distraction period of 25 days half the dogs were killed (group A) while the other half (eight dogs with limb lengthening and two dogs without) were killed after a further period of 25 days (group B). At the end of the study, the menisci were removed together with three cartilage-bone cylinders from both femoral condyles from the weight-bearing zones as well as from the corresponding tibial condyles. Serial sections from the menisci were stained with haematoxylin and eosin (H&E) and Elastica van Gieson. Sections of the cartilage-bone cylinders were stained with H&E and safranin-O. Cartilage thickness was measured and the glycosaminoglycan content of the joint cartilage was determined using microspectrophotometry. None of the histological preparations obtained from the untreated and distracted sides showed any signs of damage to the cartilage or to the menisci. There were no significant differences between cartilage thickness and proteoglycan content of the untreated side and the lengthened side. Thus, tibial lengthening using the Ilizarov method does not appear to cause acute damage to the cartilage of the knee joint or to the menisci. 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source]

    Rapid 3D-T1, mapping of the knee joint at 3.0T with parallel imaging

    S. Kubilay Pakin
    Abstract Three-dimensional spin-lattice relaxation time in the rotating frame (3D-T1,) with parallel imaging at 3.0T was implemented on a whole-body clinical scanner. A 3D gradient-echo sequence with a self-compensating spin-lock pulse cluster was combined with generalized autocalibrating partially parallel acquisitions (GRAPPA) to acquire T1, -weighted images. 3D-T1, maps of an agarose phantom and three healthy subjects were constructed using an eight-channel phased-array coil without parallel imaging and with parallel imaging acceleration factors of 2 and 3, in order to assess the reproducibility of the method. The coefficient of variation (CV) of the median T1, of the agarose phantom was 0.44%, which shows excellent reproducibility. The reproducibility of in vivo 3D-T1, maps was also investigated in three healthy subjects. The CV of the median T1, of the patellar cartilage varied between ,1.1% and 4.3%. Similarly, the CV varied between ,2.1,5.8%, ,1.4,8.7%, and ,1.5,4.1% for the biceps femoris and lateral and medial gastrocnemius muscles, respectively. The preliminary results demonstrate that 3D-T1, maps can be constructed with good reproducibility using parallel imaging. 3D-T1, with parallel imaging capability is an important clinical tool for reducing both the total acquisition time and RF energy deposition at 3T. Magn Reson Med, 2006. 2006 Wiley-Liss, Inc. [source]

    Living with severe osteoarthritis while awaiting hip and knee joint replacement surgery

    Cert HSM, Gail Elizabeth Parsons MSc
    Abstract Objectives:,To explore the lived experiences of patients with severe osteoarthritis (OA) of the hip or knee joint while awaiting joint replacement surgery. Methods:,An exploratory qualitative approach using phenomenology was adopted for the purpose of the study. Unstructured interviews were carried out on a sample of six patients who had been referred to the National Health Service waiting list for a primary hip or knee replacement. The participants were invited to share their experiences and concerns relating to how they were coping with end-stage OA of their hip or knee joint. Interviews were digitally recorded and transcribed verbatim. Narrative data were analysed using Giorgi's (1985) procedural steps to reveal themes which recurred in the participants' stories. Results:,Six themes emerged from the data, central to the experience of living with severe OA. They were: coping and living with pain; not being able to walk; coping with everyday activities; body image; advice and support available; and the effect of their disease upon family, friends and helpers. There were also a number of sub-themes associated with each major theme. Conclusions:,This study suggests that there is an absence of generic support, guidance and information relating to the management of symptoms of OA for individuals awaiting hip and knee replacement surgery. Patients awaiting hip and knee joint replacement surgery often have difficulty in managing their symptoms. Support in general appears to be dependent on the availability of resources in the primary care setting. Potential patients who are fortunate to know or meet someone who has undergone a similar procedure learn from the experience of exchanging information between themselves, along with coping strategies in the management of their symptoms. Copyright 2008 John Wiley & Sons, Ltd. [source]

    Bilateral septic arthritis of the knee joint in three children caused by unusual infectious agents

    Mustafa Hacimustafao
    First page of article [source]

    Reliability of knee joint range of motion and circumference measurements after total knee arthroplasty: does tester experience matter?

    Thomas Linding Jakobsen
    Abstract Background and Purpose.,Two of the most utilized outcome measures to assess knee joint range of motion (ROM) and intra-articular effusion are goniometry and circumference, respectively. Neither goniometry nor circumference of the knee joint have been examined for both intra-tester and inter-tester in patients with total knee arthroplasty (TKA). The purpose of this study was to determine the intra-tester and inter-tester reliability of active and passive knee joint ROM and circumference in patients with TKA when administered by physiotherapists (testers) with different clinical experience.,Method.,The design was an intra-tester, inter-tester and intra-day reliability study. Nineteen outpatients (10 females) having received a TKA were examined by an inexperienced and an experienced physiotherapist. Following a standardized protocol, active and passive knee joint ROM and circumference measurements were obtained using a universal goniometer and a tape measure, respectively. To establish reliability, intraclass correlation coefficients (ICC2,1) and smallest real difference (SRD) were calculated.,Results.,The knee joint ROM and circumference measurements were generally reliable (ICC > 0.8) within and between physiotherapists (except passive knee extension). Changes in knee joint ROM of more than 6.6 and 10 (except active knee flexion) and knee joint circumference of more than 1.0,cm and 1.63,cm represent a real clinical improvement (SRD) or deterioration for a single individual within and between physiotherapists, respectively. Generally, the experienced tester recorded larger knee joint ROM and lower circumference values than that of the inexperienced tester.,Conclusions.,In clinical practice, we suggest that repeated knee goniometric and circumferential measurements should be recorded by the same physiotherapist in individual patients with TKA. Tester experience appears not to influence the degree of reliability. Copyright 2009 John Wiley & Sons, Ltd. [source]

    Knee pain in the ACL-deficient osteoarthritic knee and its relationship to quality of life

    Michael Hartwick
    Abstract Background and Purpose Pain during activities of daily living is a common presenting complaint of individuals with knee osteoarthritis and anterior cruciate ligament injury. Knee pain is also associated with a decrease in quality of life for people with osteoarthritis. The purpose of the present study was to examine the dose,response relationship between knee joint forces and painful symptoms, and whether the acute symptoms, were associated with individuals' quality of life. Method This was a cross-sectional cohort correlation study. Seventeen individuals with anterior cruciate ligament (ACL)-deficient knees diagnosed with ipsilateral knee osteoarthritis completed the ACL quality of life questionnaire (ACL-QOL). The subjects also rated pain associated with each of five incremental isometric knee extension tests, proportional to their body weight. Analysis of variance was used to assess the association between pain and normalized torque. Linear regression was used to assess the correlation between the ACL-QOL score and the total pain experienced during the graded test. Results A strong relationship was found between the level of perceived knee pain and the amount of isometric torque produced (Pearson's r = 0.98; p<0.001). There was a statistically significant relationship between pain during the graded isometric test and the ACL-QOL (Pearson's r = ,0.56; p = 0.016). Conclusions Since knee joint compression is a function of active isometric knee extension torque, increased painful symptoms were associated with increased compression forces at the knee joint for these subjects. The relationship between pain provocation and disease-specific quality of life provides evidence for the proposed joint provocation test for this subject population. Weakness caused by osteoarthritis (OA) may, in part, be a negative conditioning response that would need to be overcome in rehabilitation. Copyright 2003 Whurr Publishers Ltd. [source]

    The Arterial Supply of the Pelvic Limb of the Adult Ostrich (Struthio camelus)

    S. M. El-Nahla
    With 25 figures Summary Blood to the pelvic limb of the ostrich is provided by the external iliac and ischiatic arteries that arise from the descending aorta. The external iliac artery (a.) gave rise to the pubic a. that supplied the obturator muscles and continued as the femoral a. The femoral a. gave off three branches: (1) cranial coxal a. to muscles above the pre-acetabular ilium; (2) cranial femoral a. to muscles cranial to the femur, the gastrocnemius muscle, hip and stifle joints and (3) medial femoral a. to muscles caudal and medial to the femur. The ischiatic a. gave rise to the caudal coxal a. that supplied muscles caudal to the femur, muscular branches to the iliotibialis lateralis muscle and to the deep femoral a. that supplied the iliofibularis muscle, cutanea femoralis caudalis and lateralis aa., and branches to the flexors of the leg and knee joint, then terminated as the sural and popliteal arteries. The sural a. supplied most of the flexors of the foot. The popliteal a. supplied the knee joint and flexors of the leg, and then terminated as the cranial and caudal tibial arteries. The caudal tibial a. supplied flexors of the foot. The cranial tibial a. provided four branches to the knee and ankle joints and to the leg. The cranial tibial a. continued into the foot as the common dorsal metatarsal a., which gave off seven different branches to the ankle and foot. With few exceptions, the arteries of the ostrich pelvic limb are similar to those of domestic fowl. [source]