Arthroscopic irrigation of the bovine stifle joint increases cartilage surface friction and decreases superficial zone lubricin

Abstract Articular cartilage is a highly nonhomogeneous, anisotropic and multiphase biomaterial consisting of mainly collagen fibrils, proteoglycans and water. Noncalcified cartilage is morphologically divided into three zones along the depth, i.e. superficial, transitional and radial zones. The thickness, density and alignment of collagen fibrils vary from the superficial zone, where fibrils are oriented parallel to the articular surface, to the radial zone where fibrils are perpendicular to the boundary between bone, and cartilage. The concentration of proteoglycans increases with the depth from the cartilage surface. These regional differences have significant implications to the mechanical function of joints, which is to be explored theoretically in the present work by considering inhomogeneity along the cartilage depth. A nonlinear fibril reinforced poroelastic model is employed as per Li et al. (1999) in which the collagen fibrils were modeled as a distinct constituent whose tensile stiffness was taken to be very high and be strain dependent but whose compressive stiffness was neglected.

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EGFR signaling is critical for maintaining the superficial layer of articular cartilage and preventing osteoarthritis initiation

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1608938113 ◽

2016 ◽

Vol 113 (50) ◽

pp. 14360-14365 ◽

Cited By ~ 35

Author(s):

Haoruo Jia ◽

Xiaoyuan Ma ◽

Wei Tong ◽

Basak Doyran ◽

Zeyang Sun ◽

...

Keyword(s):

Articular Cartilage ◽

High Surface ◽

Cartilage Degeneration ◽

Superficial Layer ◽

Joint Disease ◽

Egfr Signaling ◽

Superficial Zone ◽

Cartilage Surface ◽

Healthy Cartilage ◽

Important Regulator

Osteoarthritis (OA) is the most common joint disease, characterized by progressive destruction of the articular cartilage. The surface of joint cartilage is the first defensive and affected site of OA, but our knowledge of genesis and homeostasis of this superficial zone is scarce. EGFR signaling is important for tissue homeostasis. Immunostaining revealed that its activity is mostly dominant in the superficial layer of healthy cartilage but greatly diminished when OA initiates. To evaluate the role of EGFR signaling in the articular cartilage, we studied a cartilage-specific Egfr-deficient (CKO) mouse model (Col2-Cre EgfrWa5/flox). These mice developed early cartilage degeneration at 6 mo of age. By 2 mo of age, although their gross cartilage morphology appears normal, CKO mice had a drastically reduced number of superficial chondrocytes and decreased lubricant secretion at the surface. Using superficial chondrocyte and cartilage explant cultures, we demonstrated that EGFR signaling is critical for maintaining the number and properties of superficial chondrocytes, promoting chondrogenic proteoglycan 4 (Prg4) expression, and stimulating the lubrication function of the cartilage surface. In addition, EGFR deficiency greatly disorganized collagen fibrils in articular cartilage and strikingly reduced cartilage surface modulus. After surgical induction of OA at 3 mo of age, CKO mice quickly developed the most severe OA phenotype, including a complete loss of cartilage, extremely high surface modulus, subchondral bone plate thickening, and elevated joint pain. Taken together, our studies establish EGFR signaling as an important regulator of the superficial layer during articular cartilage development and OA initiation.

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Biomechanical Properties of the Stifle Joint Lateral Collateral Ligament in Dogs

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.1055/s-0038-1633103 ◽

1992 ◽

Vol 05 (04) ◽

pp. 158-162 ◽

Cited By ~ 1

Author(s):

D. Blackketter ◽

J Harari ◽

J. Dupuis

Keyword(s):

Mechanical Properties ◽

Cruciate Ligament ◽

Lateral Collateral Ligament ◽

Biomechanical Properties ◽

Fibular Head ◽

Joint Stability ◽

Collateral Ligament ◽

Cranial Cruciate Ligament ◽

Stifle Joint

Bone/lateral collateral ligament/bone preparations were tested and structural mechanical properties compared to properties of cranial cruciate ligament in 15 dogs. The lateral collateral ligament has sufficient stiffness to provide stifle joint stability and strength to resist acute overload following fibular head transposition.

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The Effect of Total Meniscectomy versus Caudal Pole Hemimeniscectomy on the Stifle Joint of the Sheep

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.1055/s-0038-1632463 ◽

1999 ◽

Vol 12 (02) ◽

pp. 56-63 ◽

Cited By ~ 5

Author(s):

C. R. Bellenger ◽

P. Ghosh ◽

Y. Numata ◽

C. Little ◽

D. S. Simpson

Keyword(s):

Tissue Culture ◽

Articular Cartilage ◽

Fibrous Tissue ◽

Cartilage Degeneration ◽

Medial Compartment ◽

Proteoglycan Synthesis ◽

Stifle Joint ◽

Medial Meniscectomy ◽

Tibial Condyle ◽

Articular Cartilage Degeneration

SummaryTotal medial meniscectomy and caudal pole hemimeniscectomy were performed on the stifle joints of twelve sheep. The two forms of meniscectomy produced a comparable degree of postoperative lameness that resolved within two weeks of the operations. After six months the sheep were euthanatised and the stifle joints examined. Fibrous tissue that replaced the excised meniscus in the total meniscectomy group did not cover as much of the medial tibial condyle as the residual cranial pole and caudal fibrous tissue observed following hemimeniscectomy. The articular cartilage from different regions within the joints was examined for gross and histological evidence of degeneration. Analyses of the articular cartilage for water content, glycosaminoglycan composition and DNA content were performed. The proteoglycan synthesis and release from explanted articular cartilage samples in tissue culture were also measured. There were significant pathological changes in the medial compartment of all meniscectomised joints. The degree of articular cartilage degeneration that was observed following total meniscectomy and caudal pole meniscectomy was similar. Caudal pole hemimeniscectomy, involving transection of the meniscus, causes the same degree of degeneration of the stifle joint that occurs following total meniscectomy.The effect of total medial meniscectomy versus caudal pole hemimeniscectomy on the stifle joint of sheep was studied experimentally. Six months after the operations gross pathology, histopathology, cartilage biochemical analysis and the rate of proteoglycan synthesis in tissue culture were used to compare the articular cartilage harvested from the meniscectomised joints. Degeneration of the articular cartilage from the medial compartment of the joints was present in both of the groups. Caudal pole hemimeniscectomy induces a comparable degree of articular cartilage degeneration to total medial meniscectomy in the sheep stifle joint.

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Isolated Lateral Meniscal Tear in the Dog

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.1055/s-0038-1633280 ◽

1988 ◽

Vol 01 (03/04) ◽

pp. 152-154

Author(s):

S. Johnson ◽

D. Hulse

Keyword(s):

External Rotation ◽

Femoral Condyle ◽

Meniscal Tear ◽

Lateral Meniscus ◽

Surgical Excision ◽

Human Beings ◽

Stifle Joint ◽

Microscopic Pathology ◽

Bucket Handle Tear ◽

Bucket Handle

degenerative changes of the involved stifle joint associated with a “bucket handle” tear of the caudal body of the lateral meniscus. Surgical excision of the torn section of meniscus was beneficial in the first patient but this patient had persistant difficulty with the leg after exercise. Gross and microscopic pathology of the involved stifle in the second patient showed the meniscal lesion to be associated with severe cartilage fibrillation of the overlying lateral femoral condyle. As in human beings, the mechanism of injury may have been placement of the foot during vigorous external rotation of the femur with the stifle flexed. Extension of the limb from this position could have resulted in an isolated tear of the lateral meniscus.

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Effect of Suture Type on Stifle Joint Biomechanics After Extra-Articular Repair of Cranial Cruciate Ligament Transection in the Dog

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.1055/s-0038-1633270 ◽

1991 ◽

Vol 4 (04) ◽

pp. 144-149 ◽

Cited By ~ 4

Author(s):

M. S. Bauer ◽

W. E. Blevins ◽

W. R. Widmer ◽

Jaqueline Davidson ◽

S. W. Aiken ◽

...

Keyword(s):

Cruciate Ligament ◽

Tibial Tuberosity ◽

Cranial Cruciate Ligament ◽

Stifle Joint ◽

Ligament Rupture ◽

Cruciate Ligament Rupture ◽

Before And After ◽

Joint Biomechanics ◽

Cranial Cruciate Ligament Rupture

SummaryThe effect of two suture types, monofilament polybutester and braided polyester, on stifle joint biomechanics after extra-articular repair of cranial cruciate ligament rupture was evaluated by analysis of the instant centre of motion. The instant centres of motion and resulting velocity vectors were determined radiographically on both stifles of eight fresh canine cadavers before and after cranial cruciate ligament transection. After ligament transection, all 16 stifles were repaired with an extra-articular technique utilizing a double strand of suture placed between the lateral fabella and the tibial tuberosity. One stifle on each cadaver was repaired with each suture type. The instant centres of motion and resulting velocity vectors were re-evaluated post repair. All stifles had normal instant centres of motion prior to transection of the cranial cruciate ligament. Neither ligament transection nor extra-articular repair with either suture type resulted in an abnormal change in the instant centre of motion.

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Review for "Lubricin Contributes to Homeostasis of Articular Cartilage by Modulating Differentiation of Superficial Zone Cells"

10.1002/jbmr.4226/v1/review2 ◽

2020 ◽

Keyword(s):

Articular Cartilage ◽

Superficial Zone

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Decision letter for "Lubricin Contributes to Homeostasis of Articular Cartilage by Modulating Differentiation of Superficial Zone Cells"

10.1002/jbmr.4226/v4/decision1 ◽

2020 ◽

Keyword(s):

Articular Cartilage ◽

Superficial Zone

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DETERMINATION OF PERFORMANCE INDICATORS OF THE TRUCK KrAZ-6510TE

Avtoshliakhovyk Ukrayiny ◽

10.33868/0365-8392-2020-1-261-19-26 ◽

2020 ◽

pp. 19-26

Author(s):

Olexandr Pavlenko ◽

Serhii Dun ◽

Maksym Skliar

Keyword(s):

Mathematical Model ◽

Surface Friction ◽

Building Structures ◽

Maximum Torque ◽

Military Equipment ◽

Military Vehicles ◽

Force Magnitude ◽

Vehicle Mobility ◽

The Mathematical Model

In any economy there is a need for the bulky goods transportation which cannot be divided into smaller parts. Such cargoes include building structures, elements of industrial equipment, tracked or wheeled construction and agricultural machinery, heavy armored military vehicles. In any case, tractor-semitrailer should provide fast delivery of goods with minimal fuel consumption. In order to guarantee the goods delivery, tractor-semitrailers must be able to overcome the existing roads broken grade and be capable to tow a semi-trailer in off-road conditions. These properties are especially important for military equipment transportation. The important factor that determines a tractor-semitrailer mobility is its gradeability. The purpose of this work is to improve a tractor-semitrailer mobility with tractor units manufactured at PJSC “AutoKrAZ” by increasing the tractor-semitrailer gradeability. The customer requirements for a new tractor are determined by the maximizing the grade to 18°. The analysis of the characteristics of modern tractor-semitrailers for heavy haulage has shown that the highest rate of this grade is 16.7°. The factors determining the limiting gradeability value were analyzed, based on the tractor-semitrailer with a KrAZ-6510TE tractor and a semi-trailer with a full weight of 80 t. It has been developed a mathematical model to investigate the tractor and semi-trailer axles vertical reactions distribution on the tractor-semitrailer friction performances. The mathematical model has allowed to calculate the gradeability value that the tractor-semitrailer can overcome in case of wheels and road surface friction value and the tractive force magnitude from the engine. The mathematical model adequacy was confirmed by comparing the calculations results with the data of factory tests. The analysis showed that on a dry road the KrAZ-6510TE tractor with a 80 t gross weight semitrailer is capable to climb a gradient of 14,35 ° with its coupling mass full use condition. The engine's maximum torque allows the tractor-semitrailer to overcome a gradient of 10.45° It has been determined the ways to improve the design of the KrAZ-6510TE tractor to increase its gradeability. Keywords: tractor, tractor-semitrailer vehicle mobility, tractor-semitrailer vehicle gradeability.

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