Thesis (Ph.D.)--University of Delaware, 2006. / Principal faculty advisor: Andras Z. Szeri, Dept. of Mechanical Engineering. Includes bibliographical references.

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Thesis (Doctoral)--Department of Cell and Molecular Biology, Lund University, Sweden. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (Doctoral)--Department of Cell and Molecular Biology, Lund University, Sweden. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Abstract Osteoarthritis (OA) is the most common degenerative joint disease and a growing health problem affecting more than half of the population over the age of 65. It is characterized by inflammation in the cartilage and synovium, resulting in the loss of joint structure and progressive damage to the cartilage. Many pro-inflammatory mediators are elevated in OA, including reactive oxygen species (ROS) such as nitric oxide (NO) and hydrogen peroxide (H2O2). Damaged articular cartilage remains a challenge to treat due to the limited self-healing capacity of the tissue and unsuccessful biological interventions. This highlights the need for better therapeutic strategies to heal damaged articular cartilage. Ozone (O3) therapy has been shown to have positive results in the treatment of OA; however the use of O3 therapy as a therapeutic agent is controversial. There is a perception that O3 is always toxic, whereas evidence indicates that when it is applied following a specified method, O3 can be effective in the treatment of degenerative diseases. The mechanism of action of O3 therapy in OA is not fully understood and this review summarizes the use of O3 therapy in the treatment of damaged articular cartilage in OA.

No description available.

No description available.

In this study an <i>in vitro</i> model was used to simulate joint trauma by subjecting explants of articular cartilage to a single impact load using a specially designed drop-tower loading machine for which two different loading attachments were developed. The aim was to compare the biophysical effects of impact loading on bovine and human cartilage. The proteolytic lysomal enzyme, cathepsin B and the proinflammatory mediators, prostaglandin E₂ (PGE₂) and nitric oxide (NO) have been implicated in the degradation of cartilage following trauma. This study aimed to investigate the role of these degradatory mediators. Human cartilage was found to be less damaged than bovine after impact and the type of loading attachment affected the nature of the damage observed. Following an impact load on human cartilage explants, the levels of glycosaminoglycans (GAGs), a measure of cartilage breakdown, in the culture medium and the percentage of apoptotic chondrocytes were significantly increased. The levels of pro-cathepsin B were significantly increased in the culture medium compared to unloaded controls. Addition of human cystatin C and the synthetic cathepsin B inhibitor, CA-074Me, reduced this release. However these inhibitors had no effect on the release of GAGs or the levels of apoptosis following impact. A marked increase in PGE₂ and NO was measured in the medium following an impact load, which was reduced by the selective cyclooxygenase-2 (COX-2) inhibitor, celecoxib, and the non-selective inhibitor, indomethacin. These inhibitors reduced chondrocyte apoptosis but no change was observed in the release of GAGs from the explants. This <i>in vitro</i> study indicates that cell viability and matrix degeneration are separately regulated and that it is unlikely that cathepsin B or COX-2 inhibition alone would slow down or prevent the development of secondary osteoarthritis.

Articular cartilage is a tough and resilient tissue lining the ends of articulating bones. It provides a smooth surface for joint locomotion as well as transmitting the force between bones. The main components of articular cartilage are collagen (20% w/w), proteoglycans (10% w/w) and water (70% w/w). The interactions between these three give the tissue its special characteristics. Water as a molecule is often forgotten when considering the mechanical properties of articular cartilage. This thesis aims to increase our knowledge of the role of water molecules in the load bearing mechanisms of the tissue. It will also investigate the material properties of cartilage as hydrogel. Different rates of loading (impact and slow compression) were used on partially dehydrated articular cartilage (bovine and human). The impact was also recorded using high-speed video cameras. Values of modulus of elasticity, Poisson's ratio, energetic coefficient of restitution were measured together with viscoelastic spectra, by Fourier transformation, and Dynamic Mechanical Analysis. Differential scanning calorimetry (DSC) was also performed on bovine and human articular cartilage, as well as transmission electron microscopy where different freeze substitution solvents were used. The stiffness of the tissue increased and the energetic coefficient of restitution decreased with decreasing water content. Cartilage explants had a smaller volume at the point of full strain than at the start of the impact and this volume loss was associated with the level of hydration of the tissue. Poisson's ratio was not associated with the water content of the tissue. The DSC showed that the water existed in the tissue in different environments, as the exothermic traces showed melting patterns with multiple peaks. Transmission electron micrographs revealed an area surrounding the collagen molecules that could be associated water. These results indicate that water might exist in a structured way in the tissue, and that it is important for the mechanical capabilities of the tissue.

A research report submitted to the Faculty of Health Sciences, University of Witwatersrand, Johannesburg in partial fulfilment of the requirements for the degree of Master of Science in Physiotherapy. / The purpose of this retrospective study was to assess the Subjective, objective and functional results of intra-articular anterior cruciate ligament (ACL) reconstructions using the patellar tendon. The subjects of one orthopaedic surgeon were assessed to eliminate surgical variability. Twenty active males, aged 20 - 35 were assessed twelve to fortyeight months post-operatively. Each subject completed a questionnaire and underwent various functional and subjective tests. Eighteen subjects (90 %) were satisfied with the outcome of their operation. Fourteen (70%) complained of intermittent pain or cdscomfort. Six (30%) complained of some form of post-operative giving way. Nineteen (95 %) had returned to sporting activity but most modified their sport or level of participation. Knee stability was restored post-operatively. Nineteen (95%) had a side-to-side difference of three rnillimetres (mm) or less on Lachman testing and eighteen (90 %) a side-to-side difference of 3mm or less on anterior drawer testing. Thirteen (65 %) had a 3mm or less side-to-side difference on KT1000 testing at 20 pounds (lbs) and 14 (70%) a side-to-side difference of 3mm or less on manual maximum testing. Isokinetic muscle testing revealed persistent quadriceps deficits greater than 20 % in seven subjects (35%) and three (15%) had similar hamstring deficits. Various factors may affect post-operative function. These include the length of rehabilitation, pain, residual quadriceps weakness and restoration of stability. / AC 2018