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Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

In this thesis, adaptations were made on the Hybrid Cadaveric System to accommodate new testing ramifications. The tests simulated dynamic loading (jump landings) from a 1ft. height with various degrees of valgus (fixed hamstring and quadricep forces) and various Quadricep (Q) and Hamstring (H) forces (fixed degrees of valgus) to determine how the Anterior Cruciate Ligament (ACL) and Medial Collateral Ligament (MCL) behave. The tests performed included 0Q 0H, 100Q 0H, 300Q 0H, 300Q 100H, and 5°, 15°, 25° of valgus. To determine the strain behavior of the ACL and MCL a variety of equipment was used, including electromagnetic force plate to take impact reading, cables used to create loading on the quadriceps and hamstrings, and two Differential Variance Resistance Transducers (DVRTs). These ultimately generated ACL and MCL strain allowing for a variety of strain comparisons under various circumstances. It was concluded that in a few cases there were statistically significant differences in strain for the ACL and MCL when applying various quadricep and hamstring forces (fixed valgus). It was also found that only statistical significance was present in ACL strain when comparing degrees of valgus (fixed quadricep and hamstring forces). The research concluded that muscle activation reduces strain on the ACL and MCL in these testing scenarios. It was also established that degrees of valgus effects the ACL but is negligible for the MCL. However, due to complications and variables, further testing is needed to increase accuracy and supply more definitive results. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

by Raymond Che Tin Li. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1989. / Bibliography: leaves 149-168.

The anterior cruciate ligament (ACL) is a major ligament within the knee joint. Its role is to provide stability and maintain the physiological kinetics and kinematics of the joint. ACL injuries are common as a result of sporting and traffic accidents and current therapeutic options do not fully restore the joint kinetics and kinematics. As such, patients often suffer from increased joint laxity and joint pain following an ACL reconstruction and this can lead to secondary problems such as osteoarthritis. It is believed that improving the ACL graft could help restore the normal kinetics and kinematics of the knee joint and hence postpone or prevent the onset of primary and secondary problems. Tissue engineering has the potential to provide functional tissue to repair or replace injured or diseased tissues in the patient. The ACL is a tissue which could benefit from such developments and thus improve the success of the reconstruction. However, the ACl is a complex structure made up of a highly orientated collagen hierarchy which experiences three dimensional loading in vivo. For an engineered tissue to be functional it is necessary for this orientated structure to be replicated. The appropriate structure is achieved by replication of the in vivo ACL strain pattern which requires combined tensile and torsional loading. Current custommade and commercially available bioreactors have not been able to fully replicate this motion with the necessary feedback and monitoring of mechanical parameters. The aim of this project was to develop a novel bioreactor with physiological mechanical conditioning for the tissue engineering of an anterior cruciate ligament. A bioreactor capable of applying complex tensile and torsional loading to a developing ACL was designed, manufactured and validated. The bioreactor which has been developed is a novel research tool which allows the effect of a number of parameters to be investigated in a 3D loading environment. It can be used for the engineering of connective tissues such as ligaments and tendons and has the potential to be adapted for use with other musculoskeletal tissues such as bone. It could also be used for research to understand the processes involved in the growth and development of tissues.

Periodontitis is a chronic inflammatory infection caused by the overgrowth of bacteria harbored in tooth-retained plaque. It is estimated to affect 50% of American adults over 30, with an increased incidence of up to 70% for those over 65. The disease is characterized by the destruction of the periodontal tissues, including the periodontal ligament (PDL), root cementum, and alveolar bone. As the PDL provides tooth anchorage by connecting the root cementum to the alveolar bone, damage to this tissue results in a loss of integration with the surrounding bone and cementum, eventually leading to complete tooth detachment. This is the primary reason for tooth extractions and/or loss. Current treatments for periodontitis fail to achieve consistent PDL regeneration and integration of soft and hard tissues, thus alternative approaches are needed to improve long term outcomes. This thesis focuses on the development of a biomimetic, fiber-based, polymer composite scaffold that will enable the regeneration and integration of the hard and soft tissues comprising the periodontium, while also controlling residual infection at the wound site. This work is guided by the hypothesis that a multi-phased scaffold optimized in structure and composition to promote tissue regeneration and integration, as well as control the presence of pathogenic organisms, will augment integrative periodontal healing. The first aim of this thesis investigated scaffold design parameters for ligament regeneration, exploring polymer chemistry, fiber alignment, and antibiotic dose for the support of PDL cell growth and matrix biosynthesis. In addition, the efficacy of antibiotic-containing scaffolds in controlling the growth of periodontal pathogens was evaluated. With the overarching goal of supporting hard tissue integration, aim two optimized scaffold fiber diameter, mineral composition and dose, as well as method of mineral incorporation in order to promote PDL cell viability, growth, differentiation, and mineralized matrix deposition. In the third aim of this thesis a composite scaffold was fabricated, combining the optimized elements from the previous two aims into a multi-phased system that is mimetic of the native periodontal structure. The composite scaffold was then evaluated for tissue healing as well as for integrative potential with native tissue in a tooth-in-bone explant model. Collectively, the results of this thesis demonstrates that a scaffold with optimal structure and composition for PDL growth and integration supports enhanced periodontal healing as assessed through functional evaluation and tissue biosynthesis. In summary, the studies in this thesis led to the development of a novel, anti-infective, multi-phased scaffold which promotes integrative periodontal ligament healing. The broader implications of this work, which includes the elucidation of cell-biomaterial interactions and the implementation of complex scaffold design strategies, can be extended toward the integrative and functional repair of other composite tissue systems.

by Tsang Wai Nam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 163-176). / ACKNOWLEDGMENTS --- p.i / ABSTRACT --- p.ii / Chapter CHAPTER 1: --- INTRODUCTION --- p.1 / Chapter CHAPTER 2: --- LITERATURE REVIEW --- p.5 / Chapter 2.1 --- ACL ANATOMY AND BIOMECHANICS --- p.5 / Chapter 2.1.1 --- Microscopic anatomy --- p.5 / Chapter 2.1.2 --- Gross anatomy --- p.6 / Chapter 2.1.3 --- Functions of ACL --- p.9 / Chapter 2.1.4 --- Kinematics of ACL --- p.10 / Chapter 2.1.5 --- Biomechanics of ACL --- p.12 / Chapter 2.2 --- ACL INJURY --- p.16 / Chapter 2.2.1 --- Epidemiology --- p.16 / Chapter 2.2.2 --- Mechanism of injury --- p.16 / Chapter 2.2.3 --- Clinical signs and symptoms of ACL injury --- p.17 / Chapter 2.2.4 --- Consequences after ACL injury --- p.18 / Chapter 2.3 --- SURGICAL TREATMENT OF ACL INJURY --- p.19 / Chapter 2.3.1 --- ACL reconstruction --- p.19 / Chapter 2.3.2 --- Healing of the graft --- p.20 / Chapter 2.4 --- REHABILITATION --- p.22 / Chapter 2.4.1 --- Rehabilitation of the ACL-deficient knee --- p.22 / Chapter 2.4.2 --- Rehabilitation of the ACL-reconstructed knee --- p.22 / Chapter 2.5 --- KINEMATIC MEASUREMENT --- p.33 / Chapter 2.5.1 --- Reasons for kinematic measurement --- p.33 / Chapter 2.5.2 --- Measurement methods --- p.33 / Chapter 2.6 --- ROENTGEN STEREOPHOTOGRAMMETRIC ANALYSIS (RSA) --- p.45 / Chapter 2.6.1 --- Plain radiographic method --- p.45 / Chapter 2.6.2 --- RSA --- p.45 / Chapter 2.6.3 --- Convergent versus Biplane x-ray methods --- p.46 / Chapter 2.7 --- VIDEO STEREOGRAPHY --- p.49 / Chapter 2.7.1 --- Kinematic studies --- p.49 / Chapter 2.7.2 --- Strain studies --- p.52 / Chapter 2.7.3 --- Errors from video camera measurement --- p.53 / Chapter 2.8 --- EXTERNAL MARKERS --- p.54 / Chapter 2.8.1 --- Skin markers --- p.55 / Chapter 2.8.2 --- Plate markers --- p.55 / Chapter 2.8.3 --- Skeletal markers --- p.56 / Chapter 2.8.4 --- Virtual markers --- p.58 / Chapter 2.9 --- ARTHROSCOPY --- p.61 / Chapter 2.10 --- RATIONALE AND SCOPE OF THE PROJECT --- p.63 / Chapter CHAPTER 3: --- INSTRUMENTATION --- p.69 / Chapter 3.1 --- RSA --- p.69 / Chapter 3.1.1 --- Biplane x-ray apparatus --- p.69 / Chapter 3.1.2 --- Internal markers and implant instrument --- p.70 / Chapter 3.1.3 --- Plexi-glass calibration box --- p.71 / Chapter 3.1.4 --- Transparent digitizer and computer --- p.72 / Chapter 3.1.5 --- Accuracy of the RSA --- p.74 / Chapter 3.2 --- MOUNTING JIGS AND FORCE APPLICATION SYSTEM --- p.74 / Chapter 3.3 --- VIDEO STEREOGRAPHY --- p.76 / Chapter 3.3.1 --- PEAK motion measurement system --- p.76 / Chapter 3.3.2 --- External markers --- p.79 / Chapter 3.3.3 --- Calibration frame --- p.81 / Chapter 3.4 --- ARTHROSCOPY INSTRUMENT --- p.82 / Chapter CHAPTER 4: --- METHODOLOGY --- p.84 / Chapter 4.1 --- EXPERIMENTAL SET-UP --- p.84 / Chapter 4.1.1 --- Specimens --- p.84 / Chapter 4.1.2 --- Implantation of tantalum beads into the ACL --- p.84 / Chapter 4.1.3 --- Set-up of the video motion measurement system and x-ray --- p.86 / Chapter 4.1.4 --- Mounting of cadaveric knees --- p.88 / Chapter 4.1.5 --- Mounting of external markers --- p.88 / Chapter 4.1.6 --- Pre-conditioning --- p.89 / Chapter 4.1.7 --- Application of force --- p.89 / Chapter 4.1.8 --- X-ray and video camera capturing --- p.91 / Chapter 4.1.9 --- The conditions of ACL --- p.91 / Chapter 4.1.10 --- Digitization of x-ray images --- p.91 / Chapter 4.1.11 --- Digitization of video images --- p.92 / Chapter 4.2 --- TESTING OF INSTRUMENTATION --- p.93 / Chapter 4.2.1 --- Accuracy of the PEAK motion measurement system --- p.93 / Chapter 4.2.2 --- Reliability of the experimental set-up and migration of tantalum beads --- p.94 / Chapter 4.2.3 --- "Comparison of the x, y, and z coordinates of external markers imaged by RSA and video stereography" --- p.96 / Chapter 4.3 --- PREDICTION OF LENGTH CHANGE OF ACL --- p.96 / Chapter 4.4 --- BEHAVIOR OF ACL --- p.97 / Chapter CHAPTER 5: --- DATA ANALYSIS AND STATISTICAL METHODS --- p.98 / Chapter 5.1 --- MATHEMATICAL CALCULATION --- p.98 / Chapter 5.1.1 --- RSA calculation --- p.98 / Chapter 5.1.2 --- Determination of the length changes of ACL using RSA and video stereography --- p.102 / Chapter 5.1.3 --- Calculation of center of the external markers --- p.111 / Chapter 5.2 --- ACCURACY OF THE PEAK MOTION MEASUREMENT SYSTEM --- p.113 / Chapter 5.3 --- STATISTICAL METHODS --- p.114 / Chapter 5.3.1 --- Reliability of the experimental set-up and migration of tantalum beads / Chapter 5.3.2 --- "Comparison of the x, y, and z coordinates of external markers imaged by RSA and video stereography" --- p.114 / Chapter 5.3.3 --- Prediction of length change of ACL --- p.115 / Chapter 5.3.4 --- Behavior of ACL --- p.115 / Chapter CHAPTER 6: --- RESULT --- p.116 / Chapter 6.1 --- ACCURACY OF THE PEAK MOTION MEASUREMENT SYSTEM --- p.116 / Chapter 6.2 --- RELIABILITY OF THE EXPERIMENTAL SET-UP --- p.117 / Chapter 6.3 --- MIGRATION OF TANTALUM BEADS --- p.120 / Chapter 6.4 --- "COMPARISON OF THE X，Y, AND Z COORDINATES OF EXTERNAL MARKERS IMAGED BY RSA AND VIDEO STEREOGRAPHY" --- p.123 / Chapter 6.5 --- PREDICTION OF LENGTH CHANGE OF ACL --- p.125 / Chapter 6.6 --- BEHAVIOR OF ACL --- p.129 / Chapter 6.6.1 --- Comparison of length changes in different conditions of ACL --- p.130 / Chapter 6.6.2 --- Comparison of length changes of AM and PL bundles of ACL --- p.131 / Chapter CHAPTER 7: --- DISCUSSION --- p.132 / Chapter 7.1 --- LIMITATIONS --- p.132 / Chapter 7.2 --- VIDEO STEREOGRAPHY --- p.135 / Chapter 7.2.1 --- Accuracy of the PEAK motion measurement system --- p.135 / Chapter 7.2.2 --- Prediction of length change of ACL by video stereography --- p.138 / Chapter 7.2.3 --- External markers --- p.144 / Chapter 7.3 --- BEHAVIOR OF ACL --- p.145 / Chapter 7.3.1 --- Effect of sectioning on the behavior of ACL as measured by RSA --- p.146 / Chapter 7.3.2 --- The behavior of AM and PL bundles as measured by RSA --- p.147 / Chapter 7.3.3 --- Comparison of the RSA and video stereography systems in the study of the behavior of ACL --- p.149 / Chapter 7.4 --- SOURCES OF ERROR --- p.151 / Chapter 7.5 --- CLINICAL APPLICATIONS --- p.153 / Chapter 7.5.1 --- Suggestions to the logistic of the video stereography in in vivo --- p.153 / Chapter 7.5.2 --- Suggested clinical applications --- p.156 / Chapter 7.6 --- FUTURE STUDY --- p.158 / Chapter 7.7 --- CONCLUSIONS --- p.162 / REFERENCES --- p.163 / APPENDICES --- p.177 / Chapter 1. --- Mathematical derivations for RSA system --- p.177 / Chapter 2. --- Computer program for the RSA system: BP41 EXE --- p.186 / Chapter 3. --- Computer program to find the center of the external markers: FINDCG.EXE --- p.191 / Chapter 4. --- Data and statistical results --- p.196

Resumo: O diagnóstico preciso e a elaboração de um plano de tratamento adequado podem constituir uma tarefa bastante complexa, especialmente nos traumatismos dentoalveolares, pois necessitam de uma abordagem multidisciplinar e conhecimento sobre o processo de reparo após o traumatismo. O objetivo do trabalho foi analisar o conhecimento dos cirurgiões dentistas sobre plano de tratamento das injúrias do ligamento periodontal após traumatismo dentoalveolar. Para tanto, a partir de um questionário, foram abordadas perguntas referentes ao perfil dos profissionais entrevistados e conduta frente às injúrias do ligamento periodontal (concussão, subluxação, luxação extrusiva, luxação lateral e luxação intrusiva) ocasionadas por traumatismo dentoalveolar. Seiscentos e noventa e três cirurgiões dentistas que participaram da 23ª Reunião Anual da SBPqO (2006) responderam o questionário e os dados obtidos foram submetidos à análise descritiva, enquanto o teste estatístico foi aplicado para demonstrar as freqüências e o nível de significância entre as variáveis (Teste qui-quadrado ou Teste Exato de Fisher). De acordo com os resultados obtidos, grandes dificuldades foram encontradas com relação ao plano de tratamento das luxações extrusiva, lateral e intrusiva. De maneira geral, a especialidade não influenciou na elaboração de planos adequados para as injúrias mais complexas. Foi possível concluir que os cirurgiões dentistas não apresentam conhecimento suficiente para tratar de maneira adequada as injúrias mais severas do ligamento periodontal após traumatismo dentoalveolar / Abstract: An accurate diagnosis and the establishment of an adequate treatment plan may constitute quite a complex task, particularly in cases of dentoalveolar trauma, which require a multidisciplinary approach and knowledge of the repair process in tooth injuries. The aim of this study was to analyze the dentists' knowledge of the treatment plan for periodontal ligament injuries after dentoalveolar trauma. For such purpose, a questionnaire was prepared with questions arguing about the profile of the interviewed professionals and their conduct facing periodontal ligament injuries (concussion, subluxation, extrusive luxation, lateral luxation and intrusive luxation) secondary to dentoalveolar trauma. Six hundred and ninety three dentists attending the 23rd Annual Meeting of the SBPqO (2006) filled out the questionnaire and the obtained data were subjected to descriptive analysis. Either chi-square test or Fisher's exact test was applied to determine the frequencies and the significance level among the variables. The results revealed great difficulties in establishing a treatment plan for extrusive, lateral and intrusive luxations. In general, the dental specialty of the participants did not influence the elaboration of adequate treatment plans for the most severe injuries. It could be concluded that dentists do not have sufficient knowledge to treat properly the most severe types of periodontal ligament injuries following a dentoalveolar trauma

The purpose of this study is to evaluate anatomical variations of the coracoacromial ligament (CAL) in relation to the etiology of subacromial impingement syndrome and rotator cuff tears. A knowledge and understanding of these variations will help to determine how such variations may influence the surrounding tissues and how the biomechanics of the shoulder works, as well as improving accurate diagnosis and subsequent treatment of shoulder impingement syndrome. The methodological approach involved the dissection of 220 cadaveric shoulders in the Centre for Anatomy and Human Identification (CAHID) with a mean age of 82 years (range 53 to 102 years). The CAL was classified according to its morphology and composed band number. The rotator cuff tendons were inspected for tears that were categorized into partial bursal and complete tears. Furthermore, the study inspected the CAL’s parameters and attachment sites: degenerative changes include acromial and coracoid spurs and attrition lesions at the undersurface of the acromion. Results: the multiple banded ligament was the most commonly observed type and was seen in 101 (46%) specimens. The attachment sites of the ligament varied as the size or number of bands of the ligament increased. An association was found between rotator cuff tears and shoulders which had three or more CAL bands (52%). In addition, shoulders with rotator cuff tears had wider attachments, thicker ligaments and larger subacromial insertions. Shoulders with rotator cuff tears also had a significant incidence and size of acromial spurs. The size of the spurs was correlated with the size of the CAL and attrition lesions on the undersurface of the acromion, and changes in morphology of the acromion. Attrition lesions at the subacromial insertion of the CAL were associated with tears in the rotator cuff tendons, and worsened as the size of the subacromial insertion increased. In conclusion, anatomical variations of the CAL showed a relationship with rotator cuff tears.