scholarly journals High levels of aggrecan aggregate components are present in synovial fluids from human knee joints with chronic injury or osteoarthrosis

1995 ◽  
Vol 66 (sup266) ◽  
pp. 111-115 ◽  
Author(s):  
Anthony Ratcliffe ◽  
Ronald P Grelsamer ◽  
Howard Kiernan ◽  
Fatemeh Saed-Nejad ◽  
Denise Visco
Author(s):  
Jaw-Lin Wang ◽  
Cheng-Hsien Chung ◽  
Chung-Kai Chiang

Degenerative osteoarthritis is recognized as the consequences of mechanical injuries. The abnormal impact force applied to articular cartilage would result in bone fracture or surface fissuring, and would cause the osteoarthritis [1,2]. The relation among the injury and impact energy was well studied. However, how the external energy attenuated to the internal joint is not carefully studied yet. The porcine knee joint was used as a biomechanical model for the simulation of human knee joint during impact loading. The objective of current study was to find the variation of kinetic characteristics between human and porcine knee joint during axial impact loading. Eight fresh-frozen knee joints from 10 month-old swine and seven cadaver human knee joints were used in the experiment. The mechanical responses such as forces and bending moment of knee joint, and the accelerations of femur was quantitatively analyzed. The results showed that the axial force response between human and porcine joints was similar, however, the anteroposterior shear, flexion bening moment and accelerations of these two joints were different.


1985 ◽  
Vol 225 (1) ◽  
pp. 195-201 ◽  
Author(s):  
D A Swann ◽  
F H Silver ◽  
H S Slayter ◽  
W Stafford ◽  
E Shore

Lubricin was isolated from bovine ankle, metacarpophalangeal and knee and human knee synovial fluids. The lubricins isolated from the bovine joint fluids had the same amino acid and carbohydrate compositions, but differences were observed in the relative molecular masses. The Mr values of bovine metacarpophalangeal and ankle lubricin determined by light-scattering measurements were about 200 000, whereas values of 132 000 and 143 000 were obtained for the bovine knee lubricin. The human knee lubricin had a similar carbohydrate composition to bovine knee lubricin except for the higher glucosamine content, and the amino acid composition differed slightly. The human sample had a lower glutamic acid content and a leucine/isoleucine ratio of 2:1 compared with 1:1 in the bovine. The Mr value of the human knee lubricin (166 000) was also lower than that of the bovine metacarpophalangeal and ankle samples. The Mr value of the bovine knee lubricin determined by sedimentation-equilibrium measurements was 171 000. The length measurements determined by electron microscopy and also the sedimentation measurements showed considerable polydispersity and indicate that the degree of extension of lubricin molecules can vary. Friction measurements showed that the human knee synovial-fluid lubricin had equivalent lubricating ability in a test system in vitro to that observed for lubricin isolated from normal bovine synovial fluids. The lubricating ability of lubricin was concentration-dependent, and each lubricin sample was able to act as a lubricant in vitro in an equivalent manner to whole synovial fluid at concentrations that are thought to occur in vivo.


1979 ◽  
Vol &NA; (143) ◽  
pp. 260???265 ◽  
Author(s):  
JOSEPH L. RABINOWITZ ◽  
JOHN R. GREGG ◽  
JAMES E. NIXON ◽  
H. RALPH SCHUMACHER

1970 ◽  
Vol 92 (1) ◽  
pp. 131-136 ◽  
Author(s):  
R. G. Edwards ◽  
J. F. Lafferty ◽  
K. O. Lange

The kinematics of the human knee joint and the strain of the ligaments as a function of flexion are determined analytically and experimentally. The experimental results were obtained in 13 tests of four knee joints in which the strain in each of the two collateral and two cruciate ligaments was measured with mercury strain gauges while the tibia was rotated through a flexion angle of 130 deg. The values of the relative ligament strain obtained from the analytical model are in good agreement with the experimental results.


2020 ◽  
pp. 1407-1418
Author(s):  
Enas Yahya Abdullah ◽  
Hala Khdhie

In this paper, the wear in layers of articular cartilage was calculated, parameters effective on elastic deformation were studied in normal and diseased knee joints,   and relations between elastic deformation and squeeze film characteristics under lubrication condition  were discussed with using a mathematical model. Conferring to the results obtained, elastic deformation effects on the performance of synovial human knee joint were analyzed from medical and dynamics perspectives. Relationships between elastic deformation and wear of layers were also discussed.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lena Marie Wollschläger ◽  
Karl Ludger Radke ◽  
Justus Schock ◽  
Niklas Kotowski ◽  
David Latz ◽  
...  

AbstractClinical Magnetic Resonance Imaging (MRI) of joints is limited to mere morphologic evaluation and fails to directly visualize joint or ligament function. In this controlled laboratory study, we show that knee joint functionality may be quantified in situ and as a function of graded posterior cruciate ligament (PCL)-deficiency by combining MRI and standardized loading. 11 human knee joints underwent MRI under standardized posterior loading in the unloaded and loaded (147 N) configurations and in the intact, partially, and completely PCL-injured conditions. For each specimen, configuration, and condition, 3D joint models were implemented to analyse joint kinematics based on 3D Euclidean vectors and their projections on the Cartesian planes. Manual 2D measurements served as reference. With increasing PCL deficiency, vector projections increased significantly in the anteroposterior dimension under loading and manual measurements demonstrated similar patterns of change. Consequently, if combined with advanced image post-processing, stress MRI is a powerful diagnostic adjunct to evaluate ligament functionality and joint laxity in multiple dimensions and may have a role in differentiating PCL injury patterns, therapeutic decision-making, and treatment monitoring.


Author(s):  
Ratnakar Ambade ◽  
Ankit Jaiswal

Background: It is well understood that distal femoral and proximal tibia scale is lower in case of the Asian than that of their western counterparts. Because of the Asian population's comparatively smaller structure and stature, many surgeons claim that imported implants may not be well fitted for Asian origin patients, mainly based on Western morphometry. It is very likely that an overweight section will be used in many Asian centres in most operations, resulting in low results of the procedure of the implant. For joint substitution of distal femur, careful positioning of fitted implants as well as balancing of underlying soft tissues is important. It is also important to use incredibly complex surgical procedures. To retain its usual functional motion spectrum, use of a suitable femoral part dimension is necessary. Furthermore, owing to a discrepancy between the size of the prosthesis and the bone, there could be a host of serious issues. Objectives: To calculate the anthropometric distal femur parameter and determine the distal femur variations on the right and left side of the morph metric measurement and to evaluate dimension of current TKA as related to Indian population. Methodology: This study included visiting the out patients Department of Orthopedics, at AVBRH in the age group 30-50 year during the period of June-2020 to April-2023 with sample size of 50 patients. Detailed history and clinical review will be taken, including age, sex, socio-economic background, type of employment. In all patients involved in the study in Orthopedic OPD, thorough radiological assessment of all the knee joints will be performed. The radiological test and various anthropometrics will include knee joint Simple X-ray and CT-Scan. Expected Results: We expect that from our results, anthropometric measurements of Indian population may differ from other literatures.


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