Hui, Pok Shun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 274-293). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.iv / Acknowledgements --- p.vii / Publications Based on Work in this Thesis --- p.viii / Abbreviations --- p.ix / Table of Contents --- p.xi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The Mast Cell --- p.2 / Chapter 1.1.1 --- Origin and Development of Mast Cells --- p.3 / Chapter 1.1.2 --- Heterogeneity of Mast Cells --- p.5 / Chapter 1.1.2.1 --- Heterogeneity of Rodent Mast Cells --- p.5 / Chapter 1.1.2.2 --- Heterogeneity of Human Mast Cells --- p.6 / Chapter 1.1.3 --- Activation of Mast Cells --- p.8 / Chapter 1.1.3.1 --- IgE-dependent Activation of Mast Cells --- p.8 / Chapter 1.1.3.1.1 --- FceRI Aggregation and Tyrosine Residue Phosphorylation --- p.9 / Chapter 1.1.3.1.2 --- PLC Activation and Calcium Mobilization --- p.10 / Chapter 1.1.3.1.3 --- PKC and MAPK Activation --- p.11 / Chapter 1.1.3.2 --- IgE-independent Activation of Mast Cells --- p.14 / Chapter 1.1.3.2.1 --- Activation by IgG --- p.14 / Chapter 1.1.3.2.2 --- Activation by Basic Secretagogues --- p.14 / Chapter 1.1.3.2.3 --- Activation by Calcium Ionophores --- p.15 / Chapter 1.1.4 --- Mast Cell Mediators --- p.16 / Chapter 1.1.4.1 --- Preformed Mediators --- p.16 / Chapter 1.1.4.2 --- Newly Synthesized Lipid Mediators --- p.18 / Chapter 1.1.4.3 --- Cytokines and Chemokines --- p.19 / Chapter 1.1.5 --- Pathophysiological Roles of Mast Cells --- p.21 / Chapter 1.2 --- Arthritis --- p.23 / Chapter 1.2.1 --- Epidemiology of Arthritis --- p.23 / Chapter 1.2.2 --- Clinical Features of Arthritis --- p.25 / Chapter 1.2.2.1 --- Angiogenesis and Vasodilation --- p.25 / Chapter 1.2.2.2 --- Synovial Changes --- p.25 / Chapter 1.2.2.3 --- Cartilage Degradation and Bone Erosion --- p.26 / Chapter 1.2.3 --- Pathogenesis of Arthritis --- p.27 / Chapter 1.2.3.1 --- Roles of T Cells --- p.27 / Chapter 1.2.3.2 --- Roles of B Cells --- p.28 / Chapter 1.2.3.3 --- Roles of Mast Cells --- p.28 / Chapter 1.2.3.4 --- Roles of Cytokines --- p.31 / Chapter 1.2.4 --- Treatments of Arthritis --- p.32 / Chapter 1.2.4.1 --- NSAIDs --- p.33 / Chapter 1.2.4.2 --- Glucocorticoids --- p.34 / Chapter 1.2.4.3 --- DMARDs --- p.35 / Chapter 1.2.4.4 --- New Drugs --- p.36 / Chapter 1.3 --- Proteinase-Activated Receptor (PAR) --- p.38 / Chapter 1.3.1 --- Introduction to PARs --- p.38 / Chapter 1.3.2 --- Discovery of PARs --- p.39 / Chapter 1.3.2.1 --- PAR1 --- p.39 / Chapter 1.3.2.2 --- PAR2 --- p.39 / Chapter 1.3.2.3 --- PAR3 --- p.40 / Chapter 1.3.2.4 --- PAR4 --- p.41 / Chapter 1.3.3 --- Structure of PARs --- p.43 / Chapter 1.3.4 --- Activation of PARs --- p.43 / Chapter 1.3.4.1 --- Serine Proteinases --- p.44 / Chapter 1.3.4.1.1 --- Thrombin --- p.44 / Chapter 1.3.4.1.2 --- Trypsin --- p.46 / Chapter 1.3.4.1.3 --- Mast Cell Tryptase --- p.46 / Chapter 1.3.4.2 --- PAR Activating Peptides (PAR-APs) --- p.47 / Chapter 1.3.4.3 --- Proteinase Binding and the Tethered Ligand Mechanism --- p.49 / Chapter 1.3.5 --- Signaling of PARs --- p.50 / Chapter 1.3.5.1 --- Signaling of PAR1 --- p.51 / Chapter 1.3.5.2 --- Signaling of PAR2 --- p.52 / Chapter 1.3.5.3 --- Signaling of PAR 3 and PAR4 --- p.53 / Chapter 1.3.6 --- Termination of Signals and Antagonism of PARs --- p.53 / Chapter 1.3.6.1 --- Termination of Signals by Proteolysis --- p.53 / Chapter 1.3.6.2 --- Termination of Signals by Receptor Desensitization --- p.54 / Chapter 1.3.6.3 --- Antagonism of PARs --- p.55 / Chapter 1.3.7 --- Roles of PARs in Immune Responses --- p.56 / Chapter 1.3.7.1 --- PARs and Mast Cells --- p.57 / Chapter 1.3.7.2 --- PARs and A rthritis --- p.58 / Chapter 1.4 --- Aims of Study --- p.60 / Chapter Chapter 2 --- Materials and Methods --- p.62 / Chapter 2.1 --- Materials --- p.63 / Chapter 2.1.1 --- Materials for Study of PAR Gene Expression in Mast Cells by RT-PCR --- p.63 / Chapter 2.1.1.1 --- Materials for RNA Extraction --- p.63 / Chapter 2.1.1.2 --- Materials for cDNA Synthesis by Reverse Transcription --- p.63 / Chapter 2.1.1.3 --- Materials for Gene Amplification by PCR --- p.64 / Chapter 2.1.1.4 --- Materials for Agarose Gel Electrophoresis --- p.64 / Chapter 2.1.1.5 --- Miscellaneous --- p.64 / Chapter 2.1.2 --- Materials for Study of Histamine Release from RPMCs and LAD2 Cells --- p.65 / Chapter 2.1.2.1 --- Drugs --- p.65 / Chapter 2.1.2.1.1 --- Peptides --- p.65 / Chapter 2.1.2.1.2 --- Serine Proteinases --- p.65 / Chapter 2.1.2.1.3 --- Mast Cell Secretagogues --- p.66 / Chapter 2.1.2.1.4 --- Other Drugs --- p.66 / Chapter 2.1.2.2 --- Materials for Rat Sensitization --- p.66 / Chapter 2.1.2.3 --- Materials for LAD2 Cell Culture --- p.66 / Chapter 2.1.2.4 --- Materials for Buffers --- p.67 / Chapter 2.1.2.5 --- Materials for Spectrofluorometric Analysis of Histamine Contents --- p.67 / Chapter 2.1.2.6 --- Miscellaneous --- p.68 / Chapter 2.1.3 --- Materials for Histological Study of Synovial Mast Cells --- p.69 / Chapter 2.1.3.1 --- Drugs --- p.69 / Chapter 2.1.3.2 --- Chemicals --- p.69 / Chapter 2.1.3.3 --- Miscellaneous --- p.69 / Chapter 2.1.4 --- Materials for Study of Rat Knee Joint Inflammation --- p.70 / Chapter 2.1.4.1 --- Drugs --- p.70 / Chapter 2.1.4.1.1 --- Peptides --- p.70 / Chapter 2.1.4.1.2 --- Other Drugs --- p.70 / Chapter 2.1.4.2 --- Materials for Assessment of Vascular Permeability --- p.71 / Chapter 2.1.4.3 --- Miscellaneous --- p.71 / Chapter 2.2 --- Methods --- p.72 / Chapter 2.2.1 --- Study of PAR Gene Expression in Mast Cells by RT-PCR --- p.72 / Chapter 2.2.1.1 --- Animals --- p.72 / Chapter 2.2.1.2 --- LAD2 Cell Culture --- p.72 / Chapter 2.2.1.3 --- Preparation of Buffers --- p.73 / Chapter 2.2.1.4 --- RNA Extraction --- p.73 / Chapter 2.2.1.5 --- Heparinase and DNase Treatments --- p.74 / Chapter 2.2.1.6 --- cDNA Synthesis by Reverse Transcription --- p.75 / Chapter 2.2.1.7 --- Gene Amplification by PCR --- p.75 / Chapter 2.2.1.8 --- Agarose Gel Electrophoresis --- p.77 / Chapter 2.2.2 --- Study of Histamine Release from RPMCs and LAD2 Cells --- p.77 / Chapter 2.2.2.1 --- Rat Sensitization --- p.77 / Chapter 2.2.2.2 --- Preparation of Buffers --- p.75 / Chapter 2.2.2.3 --- Preparation of Stock Solutions --- p.78 / Chapter 2.2.2.3.1 --- Stock Solutions of Peptides --- p.75 / Chapter 2.2.2.3.2 --- Stock Solutions of Serine Proteinases --- p.79 / Chapter 2.2.2.3.3 --- Stock Solutions of Mast Cell Secretagogues and Other Drugs --- p.79 / Chapter 2.2.2.4 --- Preparation of Mast Cells --- p.80 / Chapter 2.2.2.4.1 --- Isolation and Purification of RPMCs --- p.80 / Chapter 2.2.2.4.2 --- Preparation of LAD2 Cells --- p.81 / Chapter 2.2.2.4.3 --- Determination of Cell Number and Viability --- p.81 / Chapter 2.2.2.5 --- General Protocol for Histamine Release Assay --- p.82 / Chapter 2.2.2.5.1 --- RPMC Experiments --- p.52 / Chapter 2.2.2.5.2 --- LAD2 Cell Experiments --- p.53 / Chapter 2.2.2.6 --- Spectrofluorometric Analysis of Histamine Contents --- p.83 / Chapter 2.2.2.6.1 --- Manual Analysis --- p.85 / Chapter 2.2.2.6.2 --- Automated Analysis --- p.85 / Chapter 2.2.2.7 --- Data Analysis --- p.86 / Chapter 2.2.2.7.1 --- Calculation of Histamine Release --- p.86 / Chapter 2.2.2.7.2 --- Data Presentation and Statistical Analysis --- p.87 / Chapter 2.2.3 --- Histological Study of Synovial Mast Cells --- p.88 / Chapter 2.2.3.1 --- Preparation of Buffers and Chemicals --- p.88 / Chapter 2.2.3.2 --- Preparation of Drugs --- p.88 / Chapter 2.2.3.3 --- Intra-peritoneal Injections of Compound 48/80 --- p.88 / Chapter 2.2.3.4 --- Fixation --- p.89 / Chapter 2.2.3.5 --- Processing --- p.89 / Chapter 2.2.3.6 --- Embedding --- p.90 / Chapter 2.2.3 --- Sectioning --- p.90 / Chapter 2.2.3.8 --- Staining --- p.90 / Chapter 2.2.4 --- Study of Rat Knee Joint Inflammation --- p.91 / Chapter 2.2.4.1 --- Animals --- p.91 / Chapter 2.2.4.2 --- Preparation of Drugs --- p.92 / Chapter 2.2.4.3 --- Induction of Anaesthesia --- p.92 / Chapter 2.2.4.4 --- Intra-articular Injection of Drugs --- p.93 / Chapter 2.2.4.5 --- Topical Administration of Drugs --- p.93 / Chapter 2.2.4.6 --- Assessment of Mechanical Allodynia --- p.93 / Chapter 2.2.4.7 --- Assessment of Joint Oedema --- p.94 / Chapter 2.2.4.8 --- Assessment of Hyperaemia --- p.95 / Chapter 2.2.4.9 --- Assessment of Vascular Permeability --- p.95 / Chapter 2.2.4.10 --- Data Analysis --- p.96 / Chapter Chapter 3 --- Studies of Roles of PAR in Mast Cells --- p.97 / Chapter 3.1 --- Introduction --- p.98 / Chapter 3.2 --- Materials and Methods --- p.103 / Chapter 3.2.1 --- Study of PAR Gene Expression in Mast Cells by RT-PCR --- p.103 / Chapter 3.2.2 --- Study of Effects of PAR Agonists on Histamine Release from Mast Cells --- p.103 / Chapter 3.2.3 --- Study of Signaling Pathways Induced by PAR Agonists in Mast Cells --- p.104 / Chapter 3.3 --- Results --- p.105 / Chapter 3.3.1 --- Study of PAR Gene Expression in Mast Cells by RT-PCR --- p.105 / Chapter 3.3.1.1 --- PAR Gene Expression in RPMCs --- p.105 / Chapter 3.3.1.2 --- PAR Gene Expression in LAD2 Cells --- p.105 / Chapter 3.3.2 --- Study of Effects of PAR Agonists on Histamine Release from Mast Cells --- p.106 / Chapter 3.3.2.1 --- Effects of Serine Proteinases on Histamine Release from RPMCs --- p.106 / Chapter 3.3.2.1.1 --- Thrombin --- p.106 / Chapter 3.3.2.1.2 --- Trypsin --- p.106 / Chapter 3.3.2.1.3 --- Tryptase --- p.107 / Chapter 3.3.2.2 --- Effects of PAR-APs on Histamine Release from RPMCs --- p.107 / Chapter 3.3.2.2.1 --- TFLLR-NH2 (PAR1-AP) --- p.107 / Chapter 3.3.2.2.2 --- SLIGRL-NH2 (PAR2-AP) --- p.108 / Chapter 3.3.2.2.3 --- 2-Furoyl-LIGRLO-NH2 (PAR2-AP) --- p.108 / Chapter 3.3.2.2.4 --- SFNGGP-NH2 (PAR3-AP) --- p.109 / Chapter 3.3.2.2.5 --- AYPGKF-NH2 (PARrAP) --- p.110 / Chapter 3.3.2.3 --- Effects of PAR Control Peptides on Histamine Release from RPMCs --- p.111 / Chapter 3.3.2.4 --- Effects of PAR-APs on Histamine Release from LAD2 Cells --- p.111 / Chapter 3.3.3 --- Study of Signaling Pathways Induced by PAR Agonists in Mast Cells --- p.112 / Chapter 3.3.3.1 --- Effect of PTX on PAR-AP-induced Histamine Release from RPMCs --- p.112 / Chapter 3.3.3.2 --- Effect of BAC on PAR-AP-induced Histamine Release from RPMCs --- p.113 / Chapter 3.4 --- Discussion --- p.115 / Chapter 3.5 --- Figures and Tables --- p.132 / Chapter Chapter 4 --- Studies of Roles of PAR in Rat Knee Joint Inflammation --- p.175 / Chapter 4.1 --- Introduction --- p.176 / Chapter 4.2 --- Materials and Methods --- p.181 / Chapter 4.2.1 --- Histological Study of Synovial Mast Cells --- p.181 / Chapter 4.2.2 --- Study of Rat Knee Joint Inflammation Induced by Intra-articular Injections of PAR-APs --- p.181 / Chapter 4.2.3 --- Study of Rat Knee Joint Blood Flow Changes Induced by Topical Administration of PAR-APs --- p.182 / Chapter 4.2.4 --- Study of the Involvement of Bradykinin B2 Receptors in Rat Knee Joint Inflammation Induced by PAR-APs --- p.183 / Chapter 4.3 --- Results --- p.184 / Chapter 4.3.1 --- Histological Study of Synovial Mast Cells --- p.184 / Chapter 4.3.2 --- Study of Rat Knee Joint Inflammation Induced by Intra-articular Injections of PAR-APs --- p.185 / Chapter 4.3.2.1 --- Intra-articular Injections of Carrageenan and Ovalbumin --- p.185 / Chapter 4.3.2.2 --- Intra-articular Injections of PAR-APs --- p.187 / Chapter 4.3.2.2.1 --- TFLLR-NH2 (PARrAP) --- p.187 / Chapter 4.3.2.2.2 --- 2-Furoyl-LIGRLO-NH2 (PAR2AP) --- p.187 / Chapter 4.3.2.2.3 --- SFNGGP-NH2 (PARrAP) --- p.189 / Chapter 4.3.2.2.4 --- AYPGKF-NH2 (PAR4-AP) --- p.190 / Chapter 4.3.2.3 --- Intra-articular Injections of PAR Control Peptides --- p.191 / Chapter 4.3.3 --- Study of Rat Knee Joint Blood Flow Changes Induced by Topical Administration of PAR-APs --- p.191 / Chapter 4.3.3.1 --- Topical Administration of 2-Furoyl-LIGRLO-NH2 (PAR2-AP) --- p.191 / Chapter 4.3.3.2 --- Topical Administration of A YPGKF-NH2 (PAR4-AP) --- p.192 / Chapter 4.3.4 --- Study of the Involvement of Bradykinin B2 Receptors in Rat Knee Joint Inflammation Induced by PAR-APs --- p.193 / Chapter 4.3.4.1 --- Effect of HOE 140 on Rat Knee Joint Inflammation Induced by Bradykinin --- p.193 / Chapter 4.3.4.2 --- Effect of HOE 140 on Rat Knee Joint Inflammation Induced by 2-Furoyl-LIGRLO-NH2 (PAR2-AP) --- p.194 / Chapter 4.3.4.3 --- Effect of HOE 140 on Rat Knee Joint Inflammation Induced by AYPGKF-NH2 (PARrAP) --- p.195 / Chapter 4.4 --- Discussion --- p.196 / Chapter 4.5 --- Figures and Tables --- p.209 / Chapter Chapter 5 --- General Discussions and Concluding Remarks --- p.261 / Chapter 5.1 --- General Discussions --- p.262 / Chapter 5.2 --- Further Studies --- p.267 / Chapter 5.3 --- Conclusion --- p.271 / References --- p.274

Discharge readiness following total knee replacement (TKR) has often been defined using quantitative factors, such as knee range of motion or walking a specified distance. These measurements fail to include other features that could impact readiness for discharge, such as social support or patient perceptions. Most patients have positive results following TKR surgery, however others experience negative outcomes such as falls, reduced functional performance, and hospital readmission. Readiness for returning home after TKR begins with pre-operative education to prepare patients for surgery and the post-operative phase. Health care providers must have a clear understanding of patients’ perceptions of readiness to return home after surgery. It is also essential to describe the current structure of pre-operative education nationally as a mechanism for better preparing patients to return home following knee replacement. This dissertation includes three studies that explore aspects of discharge readiness following TKR including patients’ perceptions of readiness for discharge as well as the structure of pre-operative education for TKR across the United States. The first study examined patients’ experiences preparing for discharge home from the acute care setting following TKR surgery. Results indicated that patients felt prepared overall for discharge and received appropriate supports for returning home after surgery, but some felt unprepared for certain aspects of recovery such as the amount of pain experienced in the post-operative phase. The second study surveyed health care providers who participated in pre-operative education before TKR to identify the current structure of education programs in the United States. This pilot study revealed that pre-operative education teams were commonly interprofessional with education being typically provided in a group format in a single session lasting between 1 and 1.5 hours. Verbal and written instruction were common delivery methods to provide education. The final dissertation study used mixed-methods to explore the current structure of pre-operative education for TKR in the United States with a large, national sample. Orthopedic nurses completed an online survey to describe their pre-operative education program. The majority of participants provided pre-operative education as part of interprofessional teams in either a group format or a format that included both group and individual education. Verbal instruction was the most common educational delivery method followed by written instruction. Most pre-operative education classes lasted between 1 and 1.5 hours, were delivered in a single session, and included a variety of topics. Ten orthopedic nurses were then interviewed and interview transcripts were analyzed qualitatively for common themes among participants. Participants expressed that pre-operative education was a significant component impacting patient outcomes following surgery. Interprofessional pre-operative education was valued by participants, but pragmatic factors were identified as barriers to the inclusion of other disciplines within these programs. Education programs were constantly evolving based on current evidence-based practice and changes to orthopedic protocols. Descriptions of pre-operative programs nationally combined with providers’ perceptions provides a strong basis for determining best practice to support better post-operative patient outcomes. This dissertation research culminated in recommendations for best practice as well as the creation of a model, the ICF-I-EDUCATE, which combines the International Classification of Health, Functioning and Disability (ICF), interprofessional practice, and the EDUCATE model for providing patient and family education. Research is needed to examine the ICF-I-EDUCATE model in clinical practice for patients with planned TKR.

Diss. (sammanfattning) Umeå : Umeå universitet, 2009. / Härtill 5 uppsatser. Även tryckt utgåva.

[Truncated abstract] Hyaline articular cartilage is a highly specialised tissue consisting of chondrocytes embedded in a matrix of proteoglycan and collagens. Hyaline articular cartilage withstands high levels of mechanical stress and continuously renews its extracellular matrix. Despite this durability, mature articular cartilage is vulnerable to injury and disease processes that cause irreparable tissue damage. Native hyaline articular cartilage has poor regenerative capacity following injury, largely due to the tissue's lack of blood and lymphatic supply, as well as the inability of native chondrocytes to migrate through the dense extracellular matrix into the defect site. Articular cartilage injuries that fail to penetrate the subchondral bone plate evoke only a short-lived metabolic and enzymatic response, which fails to provide sufficient new cells or matrix to repair even minimal damage. Clinically, it has previously been accepted that treatment of such defects does not result in the restoration of normal hyaline articular cartilage, which is able to withstand the mechanical demands that are placed on the joint during every day activities of daily living. ... Historically, rehabilitation following ACI has not kept pace with the advances in cell culture and surgical technique. Subsequently, there exists a significant gap in knowledge regarding `best practice' in post operative rehabilitation following ACI. The importance of structured rehabilitation in ACI should not be underestimated when evaluating the clinical success of this chondral treatment. Patients should not be left to their own devices following ACI surgery, as the risk of damage to their implant (via delamination) is high if immediate postoperative movement is not controlled. Furthermore, the biological longevity and clinical success of the graft is dependent on a controlled and graduated return to ambulation and physical activity, and the biomechanical stimulation of the implanted chondrocytes.

A Síndrome da Dor Anterior no Joelho (SDAJ) caracteriza-se por uma dor difusa retropatelar e peripatelar na articulação do joelho, exacerbada por atividades de sobrecarga sobre a articulação femoropatelar. Muitos estudos têm sido realizados no sentido de compreender os mecanismos causadores da SDAJ e suas consequências. Entre os aspectos pesquisados encontram-se a ativação muscular, relação de ativação e de capacidade de geração de força entre os músculos vasto medial e vasto lateral, a força quadriciptal e dos músculos do quadril, e as alterações mecânicas do membro inferior. Segundo a literatura, um dos principais fatores de risco para o desenvolvimento dessa patologia é a fraqueza dos extensores do joelho. A fraqueza dos extensores do joelho pode estar associada à inibição muscular (IM) que o músculo quadríceps femoral sofre em função dos estímulos dolorosos. Esta alteração na geração de força e na capacidade de ativação muscular parecem alterar a morfologia do quadríceps e influenciar as alterações mecânicas ao nível da articulação femoropatelar. Para o melhor do nosso conhecimento, não foi encontrado na literatura nenhum estudo sistemático que investigasse simultaneamente os diversos aspectos da SDAJ, tentando assim estabelecer uma relação entre os aspectos morfológicos, mecânicos e elétricos dos extensores do joelho com a SDAJ. O presente estudo tem por objetivo comparar as propriedades mecânicas, morfológicas e mioelétricas dos extensores do joelho entre sujeitos acometidos pela SDAJ e um grupo controle saudável (GC). Nossa hipótese era de que os pacientes com SDAJ apresentarão uma redução nas propriedades mecânicas, morfológicas e mioelétricas dos extensores do joelho em decorrência da inibição muscular (IM) crônica produzida pela síndrome. Além disso, o estudo também tem por objetivo avaliar se existe diferença na metodologia de aplicação da técnica de interpolação de abalo para avaliação da IM do quadríceps a partir da comparação do uso de estímulos elétricos supramáximos sobre o nervo femoral (padrão ouro) com a estimulação sobre o ponto motor (nova metodologia) em sujeitos saudáveis e indivíduos com SDAJ. Nossa hipótese era de que a estimulação sobre o ponto motor será menos desconfortável que sobre o nervo femoral e os resultados de IM serão menos variáveis (com uma menor dispersão) em função desse menor desconforto. No Capítulo I, foi realizado um levantamento da literatura sobre as variáveis que foram avaliadas no decorrer do estudo, buscando informar ao leitor o que já foi feito na área, as lacunas e contradições acerca da SDAJ. No Capítulo II, foi realizado um estudo transversal sobre a avaliação da IM do quadríceps femoral, a partir da Técnica de Interpolação de Abalo (ITT), com a aplicação do abalo sobre o nervo femoral (NF) e sobre o ponto motor (PM). Vinte e nove sujeitos do sexo feminino, com idade entre 20 e 40 anos, sintomáticas (SDAJ, n=16) e assintomáticas (GC, n=13) para SDAJ, foram submetidas a avaliação da IM sobre o PM e NF no ângulo de 60° de flexão do joelho (0°=extensão máxima). Os resultados demonstraram que, para o grupo SDAJ, o PM apresenta resultados inferiores de IM comparado ao NF; já para o GC, os resultados foram semelhantes entre os dois pontos de estimulação. No Capítulo III foram realizadas avaliações da capacidade funcional, da IM e das propriedades mecânicas, morfológicas e mioelétricas dos extensores do joelho. Trinta e duas mulheres, com idade entre 20 e 40 anos, sintomáticas (SDAJ, n=16) e assintomáticas (GC, n=16) para SDAJ, foram avaliadas. Os resultados apontam para uma maior IM e reduções na capacidade funcional, no torque isométrico, na espessura da cartilagem femoropatelar e na arquitetura muscular do grupo SDAJ em relação ao GC. A revisão de literatura realizada no Capítulo I demonstrou que a literatura apresenta divergências sobre as alterações neuromecânicas decorrentes da SDAJ em mulheres. Os resultados do Capítulo II indicam que a avaliação da IM por meio da ITT é melhor tolerada por mulheres jovens sintomáticas para SDAJ quando avaliada no NF em comparação ao PM. Já no Capítulo III foram observados maiores valores de IM e reduções na capacidade funcional, torque isométrico, espessura da cartilagem femoropatelar e arquitetura muscular nos sujeitos com SDAJ em comparação ao GC saudável. / The Anterior Knee Pain (AKP) syndrome is characterized by retropatellar and peripatellar diffuse pain in the knee joint, exacerbated by overloading activities on the patellofemoral joint. Many studies have been carried out to understand the causal mechanisms of AKP and its consequences. Among the researched aspects are muscle activation, relationship of activation and capacity of strength generation between the vastus medialis and the vastus lateralis muscles, the strength of quadriceps and hip muscles, and mechanical changes of the lower limb. According to the literature, one of the main risk factors for the development of this pathology is the knee extensors weakness. This knee extensors weakness might be associated with the muscle inhibition (MI) that the femoral quadriceps muscle suffers as a result of painful stimuli. These changes in strength generation and muscle activation capacity appear to change the quadriceps morphology and influence mechanical changes at the patellofemoral joint level. To the best of our knowledge, there is no systematic study in the literature that simultaneously investigated the various aspects of AKP, trying to establish a relationship between the morphological, mechanical and electrical aspects of the knee extensors in subjects with AKP. This study aimed to compare the knee extensors mechanical, morphological and myoelectric properties between subjects affected by AKP and a control group (CG). Our hypothesis was that patients with AKP should present a reduction in the knee extensors mechanical, morphological and myoelectric properties due to chronic muscle inhibition (MI) produced by the syndrome. In addition, the study also aimed to evaluate whether there are differences in methodology for application of the interpolated twitch technique for evaluation of the quadriceps MI by comparing the use of supramaximal electrical stimulation on the femoral nerve (gold standard) with stimulation on the motor point (new methodology) in healthy subjects and subjects affected by AKP. Our hypothesis was that the stimulation on the motor point should be less uncomfortable than on the femoral nerve and MI results should be less variable (with lower dispersion) due to such lower discomfort. In Chapter I, a literature review on the variables that were evaluated throughout the study was carried out, seeking to inform the reader on what has already been done in the area, on gaps and contradictions regarding AKP. Chapter II presents a transversal study on the assessment of the quadriceps MI with the use of the Interpolated Twitch Technique (ITT), with application of twitch on the femoral nerve (FN) and on the motor point (MP). Twenty-nine women, aged between 20 and 40 years, symptomatic (AKP, n=16) and asymptomatic (CG, n=13) for AKP, were subjected to evaluation of MI on the MP and FN at an angle of 60° of knee flexion (0°=fully extended). Results showed that, for the AKP group, MP has inferior results of MI when compared to FN; results are similar between the two stimulation points for the CG. In Chapter III, evaluations of functional capacity, MI and knee extensors mechanical, morphological and myoelectric properties were carried out. Thirty-two women, aged between 20 and 40 years, symptomatic (AKP, n =16) and asymptomatic (CG, n =16) for AKP were evaluated. Results indicated greater MI and reductions in functional capacity, in isometric torque, in patellofemoral cartilage thickness and in muscle architecture in the AKP group compared to CG. Results from literature review conducted in Chapter I showed disagreement about neuromechanics changes resulting from SDAJ in women. Chapter II results indicated that the evaluation of IM through ITT is better tolerated by young women symptomatic for SDAJ when evaluated in the NF compared to the PM. Chapter III showed higher MI values and reductions in functional capacity, isometric torque, patellofemoral cartilage thickness and muscle architecture in subjects with SDAJ compared to a healthy GC.

Submitted by Luciana Sebin (lusebin@ufscar.br) on 2016-09-19T11:30:55Z No. of bitstreams: 1 TeseRSS.pdf: 3429310 bytes, checksum: 86753c807ecc922d1c172edf0e7b1472 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-20T18:09:53Z (GMT) No. of bitstreams: 1 TeseRSS.pdf: 3429310 bytes, checksum: 86753c807ecc922d1c172edf0e7b1472 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-20T18:10:02Z (GMT) No. of bitstreams: 1 TeseRSS.pdf: 3429310 bytes, checksum: 86753c807ecc922d1c172edf0e7b1472 (MD5) / Made available in DSpace on 2016-09-20T18:10:11Z (GMT). No. of bitstreams: 1 TeseRSS.pdf: 3429310 bytes, checksum: 86753c807ecc922d1c172edf0e7b1472 (MD5) Previous issue date: 2016-02-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Patellar tendinopathy (PT) is one of the most common causes of knee pain in athletes. The prevalence of PT in elite volleyball athletes can be as high as 45%. Studies assessing lower limb muscles strength and flexibility and trunk and lower limb biomechanics during sports related activities are scarce. Also, the effects of interventions focusing on jump-landing strategy modifications to reduce the overload in the knee joint in athletes with PT have not yet been investigated. The purposes of this Thesis were: to compare hip, knee and ankle torques, as well as knee and ankle flexibility between athletes with and without PT; to compare trunk and lower limb sagittal plane biomechanics during jump-landings between athletes with and without PT; to verify the effects of an intervention of hip muscles strengthening and jump-landing strategy modification on pain, function and lower limb biomechanics in a volleyball athlete with PT and; to verify the immediate effects of changing sagittal plane trunk position on lower limb biomechanics and knee pain during jump-landings in athletes with and without PT. For the isometric torque evaluations, a handheld dynamometer was used. An inclinometer was used for the flexibility tests. For the landing biomechanics evaluations, motion capture systems and force platforms were used. The athletes’ pain and disability were assessed by means of a visual analogue scale and the Victorian Institute of Sport Assessment-Patella questionnaire. Results showed that the athletes with PT presented lower hip extensor torque and lower hamstrings and ankle flexibility when compared to healthy athletes. In the biomechanical evaluation, athletes with PT displayed less hip flexion during jump-landings and smaller contribution of the hip joint for dissipation of the landing forces when compared to healthy athletes. The eight-week intervention composed by hip strengthening exercises and jump-landing strategy modification decreased pain and disability and improved lower limb biomechanics during jump-landing in an athlete with PT, both in short and long term. Finally, increasing trunk flexion during jump-landings produced immediate effects of: 1) reducing peak patellar tendon force in athletes with and without PT; 2) reducing knee pain during landings in athletes with PT. Proximal factors of the kinetic chain, such as hip strength and hip/trunk movements during jump-landings, should not be overlooked in the development of interventions for the rehabilitation of athletes with PT. / Tendinopatia patelar (TP) é uma das causas mais comuns de dor no joelho em atletas. Em atletas de elite de voleibol, a prevalência de TP pode chegar a 45%. Estudos avaliando a força e flexibilidade dos músculos do membro inferior e a biomecânica do membro inferior e tronco durante atividades relacionadas ao esporte em atletas com TP são escassos. Além disso, a eficácia de intervenções enfocando a modificação da estratégia de aterrissagem de saltos para diminuição da sobrecarga no joelho em atletas com TP ainda não foi testada. Os objetivos da presente Tese foram: comparar o torque do quadril, joelho e tornozelo, bem como a flexibilidade do joelho e tornozelo entre atletas com e sem TP; comparar a biomecânica do membro inferior e tronco no plano sagital durante aterrissagem de salto entre atletas com e sem TP; verificar os efeitos de uma intervenção de fortalecimento dos músculos do quadril e modificação da estratégia de aterrissagem de salto na dor, função e biomecânica do membro inferior de um atleta de voleibol com TP e; verificar os efeitos imediatos de se alterar a posição do tronco no plano sagital na biomecânica do membro inferior e na dor no joelho durante aterrissagens em atletas com e sem TP. Na avaliação do torque isométrico do quadril, joelho e tornozelo, um dinamômetro manual foi utilizado. Para as avaliações de flexibilidade, utilizou-se um inclinômetro. As avaliações biomecânicas da aterrissagem de saltos foram feitas com sistemas de análise de movimento e plataformas de força. Para avaliação da dor e incapacidade dos atletas foram utilizadas a escala visual analógica e o questionário Victorian Institute of Sport Assessment-Patella. Os resultados mostraram que os atletas com TP apresentaram menor torque extensor do quadril e menor flexibilidade nos isquiotibiais e no tornozelo em comparação a atletas sadios. Na avaliação biomecânica, observou-se que atletas com TP apresentaram menor flexão do quadril durante a aterrissagem e menor contribuição da articulação do quadril para a dissipação das forças da aterrissagem em comparação aos atletas sadios. A intervenção de oito semanas de fortalecimento da musculatura do quadril e modificação da estratégia de aterrissagem de salto diminuiu a dor e a incapacidade e melhorou a biomecânica da aterrissagem em um atleta com TP, tanto em curto quanto em longo prazo. Por fim, o aumento da flexão do tronco durante aterrissagens de salto teve um efeito imediato de redução no pico de força no tendão patelar em atletas com e sem TP, além de reduzir a dor no joelho em atletas com TP. Fatores proximais da cadeia cinética, como a força do quadril e os movimentos do quadril e tronco durante aterrissagens de salto, não devem ser negligenciados no delineamento de intervenções para a reabilitação de atletas com TP.

A Síndrome da Dor Anterior no Joelho (SDAJ) caracteriza-se por uma dor difusa retropatelar e peripatelar na articulação do joelho, exacerbada por atividades de sobrecarga sobre a articulação femoropatelar. Muitos estudos têm sido realizados no sentido de compreender os mecanismos causadores da SDAJ e suas consequências. Entre os aspectos pesquisados encontram-se a ativação muscular, relação de ativação e de capacidade de geração de força entre os músculos vasto medial e vasto lateral, a força quadriciptal e dos músculos do quadril, e as alterações mecânicas do membro inferior. Segundo a literatura, um dos principais fatores de risco para o desenvolvimento dessa patologia é a fraqueza dos extensores do joelho. A fraqueza dos extensores do joelho pode estar associada à inibição muscular (IM) que o músculo quadríceps femoral sofre em função dos estímulos dolorosos. Esta alteração na geração de força e na capacidade de ativação muscular parecem alterar a morfologia do quadríceps e influenciar as alterações mecânicas ao nível da articulação femoropatelar. Para o melhor do nosso conhecimento, não foi encontrado na literatura nenhum estudo sistemático que investigasse simultaneamente os diversos aspectos da SDAJ, tentando assim estabelecer uma relação entre os aspectos morfológicos, mecânicos e elétricos dos extensores do joelho com a SDAJ. O presente estudo tem por objetivo comparar as propriedades mecânicas, morfológicas e mioelétricas dos extensores do joelho entre sujeitos acometidos pela SDAJ e um grupo controle saudável (GC). Nossa hipótese era de que os pacientes com SDAJ apresentarão uma redução nas propriedades mecânicas, morfológicas e mioelétricas dos extensores do joelho em decorrência da inibição muscular (IM) crônica produzida pela síndrome. Além disso, o estudo também tem por objetivo avaliar se existe diferença na metodologia de aplicação da técnica de interpolação de abalo para avaliação da IM do quadríceps a partir da comparação do uso de estímulos elétricos supramáximos sobre o nervo femoral (padrão ouro) com a estimulação sobre o ponto motor (nova metodologia) em sujeitos saudáveis e indivíduos com SDAJ. Nossa hipótese era de que a estimulação sobre o ponto motor será menos desconfortável que sobre o nervo femoral e os resultados de IM serão menos variáveis (com uma menor dispersão) em função desse menor desconforto. No Capítulo I, foi realizado um levantamento da literatura sobre as variáveis que foram avaliadas no decorrer do estudo, buscando informar ao leitor o que já foi feito na área, as lacunas e contradições acerca da SDAJ. No Capítulo II, foi realizado um estudo transversal sobre a avaliação da IM do quadríceps femoral, a partir da Técnica de Interpolação de Abalo (ITT), com a aplicação do abalo sobre o nervo femoral (NF) e sobre o ponto motor (PM). Vinte e nove sujeitos do sexo feminino, com idade entre 20 e 40 anos, sintomáticas (SDAJ, n=16) e assintomáticas (GC, n=13) para SDAJ, foram submetidas a avaliação da IM sobre o PM e NF no ângulo de 60° de flexão do joelho (0°=extensão máxima). Os resultados demonstraram que, para o grupo SDAJ, o PM apresenta resultados inferiores de IM comparado ao NF; já para o GC, os resultados foram semelhantes entre os dois pontos de estimulação. No Capítulo III foram realizadas avaliações da capacidade funcional, da IM e das propriedades mecânicas, morfológicas e mioelétricas dos extensores do joelho. Trinta e duas mulheres, com idade entre 20 e 40 anos, sintomáticas (SDAJ, n=16) e assintomáticas (GC, n=16) para SDAJ, foram avaliadas. Os resultados apontam para uma maior IM e reduções na capacidade funcional, no torque isométrico, na espessura da cartilagem femoropatelar e na arquitetura muscular do grupo SDAJ em relação ao GC. A revisão de literatura realizada no Capítulo I demonstrou que a literatura apresenta divergências sobre as alterações neuromecânicas decorrentes da SDAJ em mulheres. Os resultados do Capítulo II indicam que a avaliação da IM por meio da ITT é melhor tolerada por mulheres jovens sintomáticas para SDAJ quando avaliada no NF em comparação ao PM. Já no Capítulo III foram observados maiores valores de IM e reduções na capacidade funcional, torque isométrico, espessura da cartilagem femoropatelar e arquitetura muscular nos sujeitos com SDAJ em comparação ao GC saudável. / The Anterior Knee Pain (AKP) syndrome is characterized by retropatellar and peripatellar diffuse pain in the knee joint, exacerbated by overloading activities on the patellofemoral joint. Many studies have been carried out to understand the causal mechanisms of AKP and its consequences. Among the researched aspects are muscle activation, relationship of activation and capacity of strength generation between the vastus medialis and the vastus lateralis muscles, the strength of quadriceps and hip muscles, and mechanical changes of the lower limb. According to the literature, one of the main risk factors for the development of this pathology is the knee extensors weakness. This knee extensors weakness might be associated with the muscle inhibition (MI) that the femoral quadriceps muscle suffers as a result of painful stimuli. These changes in strength generation and muscle activation capacity appear to change the quadriceps morphology and influence mechanical changes at the patellofemoral joint level. To the best of our knowledge, there is no systematic study in the literature that simultaneously investigated the various aspects of AKP, trying to establish a relationship between the morphological, mechanical and electrical aspects of the knee extensors in subjects with AKP. This study aimed to compare the knee extensors mechanical, morphological and myoelectric properties between subjects affected by AKP and a control group (CG). Our hypothesis was that patients with AKP should present a reduction in the knee extensors mechanical, morphological and myoelectric properties due to chronic muscle inhibition (MI) produced by the syndrome. In addition, the study also aimed to evaluate whether there are differences in methodology for application of the interpolated twitch technique for evaluation of the quadriceps MI by comparing the use of supramaximal electrical stimulation on the femoral nerve (gold standard) with stimulation on the motor point (new methodology) in healthy subjects and subjects affected by AKP. Our hypothesis was that the stimulation on the motor point should be less uncomfortable than on the femoral nerve and MI results should be less variable (with lower dispersion) due to such lower discomfort. In Chapter I, a literature review on the variables that were evaluated throughout the study was carried out, seeking to inform the reader on what has already been done in the area, on gaps and contradictions regarding AKP. Chapter II presents a transversal study on the assessment of the quadriceps MI with the use of the Interpolated Twitch Technique (ITT), with application of twitch on the femoral nerve (FN) and on the motor point (MP). Twenty-nine women, aged between 20 and 40 years, symptomatic (AKP, n=16) and asymptomatic (CG, n=13) for AKP, were subjected to evaluation of MI on the MP and FN at an angle of 60° of knee flexion (0°=fully extended). Results showed that, for the AKP group, MP has inferior results of MI when compared to FN; results are similar between the two stimulation points for the CG. In Chapter III, evaluations of functional capacity, MI and knee extensors mechanical, morphological and myoelectric properties were carried out. Thirty-two women, aged between 20 and 40 years, symptomatic (AKP, n =16) and asymptomatic (CG, n =16) for AKP were evaluated. Results indicated greater MI and reductions in functional capacity, in isometric torque, in patellofemoral cartilage thickness and in muscle architecture in the AKP group compared to CG. Results from literature review conducted in Chapter I showed disagreement about neuromechanics changes resulting from SDAJ in women. Chapter II results indicated that the evaluation of IM through ITT is better tolerated by young women symptomatic for SDAJ when evaluated in the NF compared to the PM. Chapter III showed higher MI values and reductions in functional capacity, isometric torque, patellofemoral cartilage thickness and muscle architecture in subjects with SDAJ compared to a healthy GC.

Orientador: Sérgio Rocha Piedade / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-24T17:24:46Z (GMT). No. of bitstreams: 1 Inada_MauroMitsuo_M.pdf: 1830767 bytes, checksum: 4b553d2b930c1c4c78288e15aa3c117e (MD5) Previous issue date: 2014 / Resumo: Introdução: A lesão bicruzado do joelho é rara e está frequentemente associada a traumas de alta energia, sendo o procedimento cirúrgico o tratamento instituído devido a sua complexidade. Objetivo: Avaliar os resultados clínicos e funcionais de pacientes submetidos a reconstrução bicruzado do joelho, realizada em dois tempos cirúrgicos, utilizando os Escores de Lysholm, Tegner, KOOS e SF-36. Materiais e Métodos: 25 pacientes (20 homens e 5 mulheres) foram avaliados, idade média de 32,3 anos (17 a 53 anos), IMC médio de 26,2(18,9 a 34,9 Kg/m²), tempo de lesão de 18,3 meses (lesões crônicas). Quanto ao mecanismo de lesão, os acidentes auto-moto-ciclístico responsáveis por 72% dos casos, a prática esportiva por 16% e queda ou entorse por 12%. Inicialmente, foi utilizada a técnica Inlay para a reconstrução do LCP, utilizando o terço central do tendão patelar. Após um intervalo mínimo de 3 meses realizou-se a reconstrução do ligamento cruzado anterior via artroscópica, utilizando tendões flexores. Foram observadas as seguintes lesões associadas: condral em 7 pacientes (28%), meniscal em 16 pacientes (64%), lesões ligamentares associadas em 12 pacientes (48%). Procedimento cirúrgico adicional foram necessários em 4 pacientes (tendão patelar em 2 casos e ligamento colateral medial em 2 pacientes). Resultados: Com seguimento pós-operatório médio de 24,8 meses, em 60% dos casos a gaveta posterior foi classificada como zero e + (0,5 cm), enquanto 40% foram classificados como ++ (até 1cm). 60% dos pacientes obtiveram Escore de Lysholm bom/excelente. O Escore de atividade Tegner apresentou queda no nível de atividade física pós-reconstrução bicruzado, em comparação com o nível de atividade física pré-lesão, com relevância estatística. Entretanto, apenas 1 paciente retornou ao mesmo nível de atividade pré-lesão. A análise estatística revelou que o tempo de lesão influenciou negativamente os resultados clínicos pós-operatórios, em particular os parâmetros atividades esportivas/recreativas, do questionário KOOS, além dos domínios capacidade funcional, limitação dos aspectos físicos, vitalidade e saúde mental, do questionário SF-36. Por outro lado, variáveis como idade, IMC, presença de lesões condrais, meniscais e ligamentares associadas, assim como gaveta posterior residual não afetaram o resultado final. Conclusão: neste estudo o tempo de lesão teve um impacto negativo no prognóstico pós-operatório da reconstrução bicruzado, realizado em dois tempos cirúrgicos. Entretanto, é importante ressaltar que outras variáveis estudadas devem ser consideradas. Palavras-chave: ligamento cruzado posterior, ligamento cruzado anterior, joelho, traumatismos do joelho / Abstract: Introduction: Bicruciate lesions of the knee are rare and often related to high-energy traumas. A surgical procedure is used because of their complexity. Objective: to assess the clinical and the functional outcomes after two-stages bicruciate knee reconstruction using the Lysholm, Tegner, KOOS and SF-36 scores. Materials and methods: 25 patients (20 males and 5 females) were evaluated, mean age 32,3 years (17-53 years), mean BMI 26,2 (18,9-34,9), mean duration of lesion 18,3 months (chronic lesions). Regarding the mechanism of injury, car, motorcycle and bicycle accidents were responsible for 72%, while sports practices 16% and falls or sprains 12%. The Inlay technique was applied in PCL reconstruction using the central 1/3 of the patellar tendon. After 3 months minimum interval, ACL reconstruction was arthroscopically performed using flexor tendons. The following intraoperative lesions were detected: chondral ¿ 07 patients (28%); meniscal ¿ 16 patients (64%); associated ligament lesions ¿ 12 (48%). An additional surgical procedure was required for 4 patients (patellar tendon ¿ 2 cases, CML ¿ 2 cases). Results: With a 24,8 month mean postoperative follow-up of the cases, the posterior drawer test rated zero or + (0,5 cm) were observed in 60% of the patients, while 40% as ++ ( 1cm) and 60% of patients rated good/excellent condition (Lysholm). The Tegner activity score revealed that postoperative physical activity was less than physical activity level before the lesion and and the reduction was statistically significant. Moreover, only one patient achieved the pre-lesion activity level. The statistical analysis revealed that duration of lesion negatively influenced postoperative clinical results, especially regarding parameters such as sports/recreative activities (KOOS) and physical functioning, limitation of physical aspects, vitality and mental health (SF-36). However, in this study, the variables such as age, BMI, presence of chondral, meniscal, ligament lesions and residual posterior drawer did not affect the final result. Conclusion: The results obtained by this study concluded that duration of lesion had a negative impact on postoperative prognosis. However, it is important that other analyzed variables should also be considered. Keywords: posterior cruciate ligament, anterior cruciate ligament, knee, knee injury / Mestrado / Fisiopatologia Cirúrgica / Mestre em Ciências

Le but de cette thèse était d'étudier, in vivo, la cinématique en 3D du genou lors de la marche sur des patients souffrant d'arthrose du genou et de quantifier l'apport de l'arthroplastie totale du genou (PTG) sur la restauration d'une cinématique normale. Trente patients et un groupe de contrôle composé de 12 participants du même âge ont été inclus dans la première étude. Sur ces 30 patients, nous avons obtenu des évaluations de suivi après l'arthroplastie totale du genou sur 20 patients, avec un délai moyen de 11 mois. L'analyse cinématique tridimensionnelle du genou a été réalisée en utilisant le système KneeKGTM. Cette analyse de la marche a révélé que la cinématique de genou avec arthrose médiale diffère de la cinématique du genou sain. Le groupe avec arthrose du genou montrait une stratégie de raidissement de la marche en présentant une réduction de mouvement non seulement dans le plan sagittal, mais aussi dans le plan axial. Après PTG, les patients avaient de meilleurs paramètres cliniques, spatio-temporels et cinématiques. Malgré les améliorations, la cinématique du genou lors de la marche dans le groupe PTG différaient de celle du groupe contrôle / Patients with knee osteoarthritis tend to modify spatial and temporal parameters during walking to reduce the pain. There are common gait features which are consistently shown to be significantly linked to osteoarthritis severity such as knee adduction moment, knee flexion angle, stiffness and walking speed. Total knee arthroplasty (TKA) is considered the gold standard treatment for end-stage knee osteoarthritis. Nearly a million of total knee prosthesis are implanted worldwide each year. However, reduced physical function of the knee is partly, but apparently not fully, remedied by surgery. The purpose of this thesis was to investigate the in vivo, three dimensional knee kinematics during gait at the patients with knee osteoarthritis and the influence of total knee arthroplasty on restoration of normal kinematics. Weight bearing kinematics in medial OA knees differ from normal knee kinematics. Knee OA group showed an altered “screw-home” mechanism by decreased excursion in sagittal and axial tibial rotation and a posterior translation of the tibia. Following TKA, patients had better clinical, spatiotemporal and kinametic parameters. They walked longer, faster and with a better range of motion. Despite improvements, the knee kinematics during gait in TKA group differed from healthy control group. They had a lower extension, lower range of axial rotation and an increased tibial posterior translation. Future research should be focused on comparing different designs of prosthesis pre- and post operatively in a longer follow-up delay

The aim of this thesis was to investigate how to construct a system to measure load in a mobile unicompartmental knee replacement (UKR) bearing. In vivo loads have been measured in a total knee replacement (TKR), but with TKR the kinematics are different from those of the normal knee, whereas they are close to normal in a mobile UKR, so the loads measured by an instrumented UKR would be more representative of the normal knee. On the principle of measuring compression of an object under load, the load may be estimated. Compression measurement using a capacitive sensor was the optimal solution to measure load, based on life expectancy of the sensor and bearing integrity. A capacitive sensor within a polyethylene (UHMWPE) bearing has not been used before. The visco-elastic and temperature dependent properties of UHMWPE were determined with experiments. UHMWPE had an approximately linear response after ten minutes of applying a constant load. A temperature sensor should be used in vivo to compensate for temperature effects acting on the elastic modulus of UHMWPE. Finite element modelling demonstrated that positioning the sensor under the centre of the bearing concavity resulted in the largest capacitive change. The influence of various dimensional parameters on sensor output was simulated, and the conclusion was that the sensor only needs to be calibrated once. An electronic module inserted into a bearing had less than 5 % influence on bearing compression. Capacitive sensors were made from polyimide, using standard production methods, and embedded within a UKR bearing using the standard compression moulding process. The embedded sensor had a second order low pass frequency response, with a corner frequency of 9 Hz, twice the frequency required for typical functional loading such as gait. Physiological load signals, gait and step up/down, were applied to the bearing. The capacitance to load response was approximately linear. Load was estimated using a linear method and a dynamic method. The linear method performed best, with an accuracy of force estimation better than 90 %. In vitro tests were performed using a commercially available transceiver, two stan- dard antennas and a custom antenna, designed to be incorporated in the bearing. Wireless communication between an implanted custom antenna and an external an- tenna was shown to be feasible. Experiments were also performed that demonstrate that inductive powering of the bearing was feasible. In addition to load measurement, a proposal for dynamic measurement of the orien- tation angles of both the tibia and the femur was made. Power and volume calculations showed that it is possible to place an electronic module within the bearing. This thesis has not only demonstrated that it is feasible to make an instrumented bearing for UKR but has also provided a basic design for manufacturing.