With the increasing advocacy for maintaining a healthy lifestyle in regards to exercise and the average age of the population in the U.S. growing older, there has been an increased incidence of arthritic knee damage as a result of osteoarthritis. Once non-procedural methods of treatment have been exhausted, such as NSAIDs and physical therapy, the most effective therapy to regain previous range of motion and quality of life is total knee arthroplasty (TKA). Additionally, TKA is useful to treat patients with rheumatoid disease once their knees have reached end-stage cartilage damage, although it does not restore function as well in these patients as it does in patients with osteoarthritis. Current technological developments have produced prostheses that mimic physiological movement and allow attachment of components positioned similarly to ligaments in the human knee, providing better longevity and functional recovery from the damaged state. The TKA procedure has become fast-tracked to limit the length of stay for patients and the cost to both the individual and the hospital. Though this change to fast-track procedures has helped limit post-operative complications, such as venous thromboembolism, multiple comorbidities and componentry failure continue to increase the risk of failure or revision of the procedure. With the projected increase in the need for TKAs in the future, it is important to review factors that may influence access and success of this procedure, for example, the effect socioeconomic status has on the ability of different patients to receive quality replacements and experience sustained quality of life. Multiple studies have shown that utilization of TKA differs between low income and high income populations, with racial minority populations undergoing the procedure less often as they represent a greater percentage of low income populations. Interestingly, low income patients report greater improvement in function when compared to high income patients, most likely due to low income patients being admitted with more severe knee damage when compared to the other population. Their satisfaction, along with financial constraints and insurance, are factors that lower the rate of revision for low income populations even though their measured range of motion post-operatively is not as good as that in high income populations on average. Social support has been determined to be a significant factor in determining whether patients will undergo TKA and follow the rehabilitation prescribed to them appropriately. Studies have shown less social support reported from minority groups, but not low income cohorts specifically. Using the current knowledge of the impact these differences in socioeconomic status can have on the outcomes of TKA, can help create healthcare environments which will optimize the success rate of TKA for all patients, regardless of socioeconomic status, and prevent unnecessary strain on the healthcare system due to avoidable post-operative issues. Future studies should determine what policies and procedures can be implemented to help aid patients, such as greater social support, and to support hospitals with limited resources in an effort to improve surgical outcomes.

This thesis is missing pages 98-107, all of which are not in the other copies of the thesis. -Digitization Centre / In total knee arthroplasty with bone defect of the tibia, it was believed that with older designs of tibial tray, both block and stem augments must be used with the tibial tray to improve the knee stability. Obviously, the extended stem causes more difficulties to the surgery as well as more suffering to the patients. Getting rid of the extended stem and still maintaining enough stability is therefore very desirable. The newest tray design, Deltafit Keel tray, which provides much more contact with the human bone structure, may provide enough stability without the extra long stem. The objective in this project is to answer the questions - Is the stem augmentation definitely required alongside the block implant for the cases of bone defect in TKA (Total Knee Arthroplasty) when using the Deltafit Keel tibial tray design? In other words, does the configuration of Deltafit Keel tray with a block provide enough stability in the cases of bone defect? In order to give a reliable answer, three configurations have been studied by conducting both experiments and FEA simulation. The three cases are Deltafit Keel tibial tray only (case 1-no bone defect defect), tray with block augment (case 2-with bone defect assumed) and tray with block and extended stem (case 3-with bone defect assumed). In this study, three commercially available composite bones with isotropic material properties are utilized. For each configuration, the bones are clamped in a testing apparatus and 3000 N static compressive load is imposed on the top surface of the tibia tray at central, medial and lateral locations. In experiment, the strains and displacements at strategically selected locations were measured by strain rosettes (strain gages) and DVRT (Differential Variable Reluctance Transducer) displacement transducers, respectively. In order to simulate the three cases, FE model is established by employing several advanced software including CATIA, True Grid Mesh generator and Abaqus. In order to compare with the experimental results, nine cases (three implant configurations with three different loading positions for each) have been simulated using Abaqus/Standard 6.4. In addition to the nine-case studies, the influence of load offsetting is also investigated by shifting the nodal load along medial-lateral and anterior-posterior directions. It is found that load shifting one node in either direction does not cause significant change in either strain or displacement. Furthermore, FE results of adjacent elements are checked as well and no sudden changes are observed. Since the discrepancy of the output from adjacent elements is negligible, an average value of the elements can be used to represent the output in a small region to compare the experimental strain measured by strain rosettes. Both the experimental data and FEA simulation results lead to the conclusion that comparable stability can be achieved with the configuration of Deltafit Keel tibial tray and a block as compared to the case of Deltafit Keel tray only without bone defect. Moderate improvement of stability, but with significant stress shielding, is found when the extended stem is implanted. For the amount of bone defect and the bone material properties used in this study, the Deltafit Keel tray with a block is the best choice because it is able to provide adequate stability and avoid excessive stress shielding. The loss of a substantial amount of bone to implant an extended stem to trade for the excessive stability may not be worthwhile. Besides, stress shielding is a potential problem which may exist if the extended stem is used. / Thesis / Master of Applied Science (MASc)

Ankle arthritis is a debilitating condition that causes severe pain and decreased function in the affected limb on the order of end-stage hip arthrosis, end-stage kidney disease, and congestive heart failure. Total ankle replacement is a viable surgical option for treating end-stage ankle arthritis, but few have studied its effects on balance over time. Therefore, the purpose of this study was to test the accuracy of a single-marker method of tracking center of mass, evaluate center of pressure measurements in total ankle replacement patients, and analyze lower extremity joint contributions over a two-year recovery period. Subjects stood on two force platforms for ten seconds in different conditions, and relevant variables were calculated from the force platform and 3D motion capture data. Results showed that increasing recovery time restored partial symmetry between the surgical and non-surgical limbs in ground reaction force, ankle range of motion, and ankle and hip moment contribution in static balance tasks. Furthermore, the ankle and hip may have different roles in postural stability. The results of the studies suggest that total ankle replacement is an effective treatment for end-stage ankle arthritis in terms of restoring postural stability. While patients may not have returned to the level of healthy control subjects, they are more functional and more stable after a two-year recovery period. While further work is needed, the results are encouraging for the outlook of ankle arthritis patients who may need total ankle replacement surgery. / Master of Science / Ankle arthritis is a debilitating condition that causes severe pain and decreased function in the affected limb on the order of end-stage hip arthrosis, end-stage kidney disease, and congestive heart failure. Total ankle replacement is a viable surgical option for treating end-stage ankle arthritis, but few have studied its effects on balance over time. Therefore, the purpose of this study was to test the accuracy a simplified method to track the center of gravity of the human body, evaluate center of pressure (the point where the force of body weight acts) measurements in total ankle replacement patients, and analyze lower extremity joint contributions to balance over a two-year recovery period. Subjects stood on two force measurement platforms for ten seconds in different conditions, and relevant variables were calculated from the force platform and 3D motion capture data. Results showed that increasing recovery time restored partial symmetry between the surgical and non-surgical limbs in weight-bearing force, center of pressure excursion, and ankle and hip contributions to stability. The results of the study suggest that total ankle replacement is an effective treatment for end-stage ankle arthritis in terms of restoring balance. While patients may not have returned to the level of healthy people, the results suggest they are more stable after a two-year recovery period. While further work is needed, the results are encouraging for the outlook of ankle arthritis patients who may need total ankle replacement surgery.

Abstract Background: Osteoarthritis (OA) is a prevalent joint disease causing significant disability, particularly in the knee often treated end-stage with joint replacement surgery. While partial knee arthroplasty (PKA) is noted for quicker recovery and better functionality compared to total knee arthroplasty (TKA), its underutilization highlights a gap in surgical decision-making, driven by a lack of objective data on pre-operative functional differences. Methods: This prospective observational study, conducted from November 2023 to April 2024 at St. Joseph’s Healthcare Hamilton, included 34 end-stage OA patients scheduled for knee arthroplasty. Participants underwent pre-operative functional assessments using markerless motion capture technology to analyze gait and mobility during walking and sit-to-stand tests. Results: The study found no significant differences in basic gait and sit-to-stand metrics between the PKA and TKA groups at a preferred pace. However, at a faster pace, PKA patients demonstrated greater adaptability, showing significant increases in peak stance knee flexion, knee flexion excursions, and stride length, compared to TKA patients whose gait patterns remained consistent across speeds. Conclusion: PKA patients exhibit greater functional adaptability in their pre-operative state, suggesting potential underestimation of their capabilities in current surgical evaluations. Incorporating varied-pace walking tests in pre-operative assessments may provide deeper insights into functional capabilities, influencing more tailored surgical decisions and potentially increasing the application of PKA in suitable candidates. / Thesis / Master of Applied Science (MASc)

Class of 2017 Abstract / Objectives: The first aim is to assess efficacy of aspirin versus enoxaparin in preventing a venous thromboembolism (VTE) after a total knee arthroplasty (TKA) or total hip arthroplasty (THA) within 30 days after discharge. The second aim is to assess the safety of aspirin versus enoxaparin in preventing major bleeding events after a TKA or THA within 30 days after discharge. Methods: This study was a retrospective cohort study with data obtained from an online Veterans Affairs (VA) hospital database. For analysis, the primary outcome was assessed with a Chi-Square test, and the secondary outcome was reported with descriptive statistics.Results: Results: Demographics for 374 patients (TKA, n = 275; THA, n = 99): 90% male, average age of 65, average body mass index (BMI) of 32, 26% smokers, 72% had a history of hypertension, and 60% had a history of dyslipidemia. VTE events 30 days post-operatively: enoxaparin (n = 2), enoxaparin/aspirin (n = 1), and aspirin (n = 2) (P-value = 0.78). Safety events (major bleeding events): enoxaparin (n = 42), enoxaparin/aspirin (n = 7), and aspirin (n = 4). Conclusions: There was no significant difference between the treatment groups for VTE rate 30 days post- operation. The enoxaparin treatment group had the greatest number of safety events compared to the other groups.

<p><strong>Syfte</strong>: Syftet var att finna skillnader och samband i self-efficacy (SE) – med avseende på typ av artroplastik, kön och ålder – inför två förflyttningar. Detta för att se vilka patienter som kan vara i större behov av att stärka SE postoperativt.</p><p><strong>Metod:</strong> Studien gjordes på inneliggande patienter som genomgått en höft- eller knäartroplastik. Ett för undersökningen framställt frågeformulär undersökte de 117 deltagarnas SE inför att sätta sig upp på sängkanten samt gå med hjälpmedel. Deltagarna skattade SE inför förflyttningarna första eller andra dagen efter operationen.</p><p><strong>Resultat</strong>: Deltagare som hade genomgått en knäartroplastik skattade signifikant högre SE inför att sätta sig upp på sängkanten än de som hade genomgått en höftartroplastik. Männen skattade signifikant högre SE inför båda momenten jämfört med kvinnorna. Det fanns en låg korrelation mellan stigande ålder och låg SE inför att gå med hjälpmedel.</p><p><strong>Konklusion:</strong> Resultaten tyder på att SE inför förflyttningarna skiljer sig mellan patienter. Detta bör behandlande sjukvårdspersonal ta hänsyn till i ett postoperativt skede för att undvika immobiliseringskomplikationer hos patienterna.</p>

The design of an uncemented hip arthroplasty implant affects its long-term survival. Characteristics such as the form and the finish of the implant are crucial in order to achieve the best possible conditions for long-term implant survival. In this thesis we hypothesized that different shapes of stems and cups used in primary and revision total hip arthroplasty (THA), and their finish with hydroxyapatite (HA) coating affect implant stability and thus long-term survival. In 2 prospective cohort studies the clinical outcome, the stability measured with radiostereometric analysis (RSA), and the periprosthetic changes in bone mineral density (BMD) measured with dual-energy x-ray absorptiometry (DXA) were investigated in 2 uncemented THA implants – the CFP stem and the TOP cup. In 3 register studies the effect of HA coating on uncemented THA implants used in primary and revision arthroplasty was investigated. Both implants investigated in the prospective cohort studies showed an excellent short-term clinical outcome with good primary stability, but neither their novel form nor the finish with HA protected the implants from the proximal periprosthetic demineralization that usually occurs around other uncemented THA implants. The register studies revealed that HA coating on cups used in primary and revision THA is a risk factor for subsequent revision of the implant. The use of HA coating on the stem in primary THA did not affect long-term survival. Additionally, the shape of an implant plays a crucial role for implant stability and survival. In conclusion, this thesis highlights that the finish of implants with HA coating does not prevent periprosthetic proximal femoral bone loss and can even enhance the risk of revision of both primary and secondary cups. Importantly, the shape of uncemented THA implants affect their stability, showing that the implant form is a crucial factor for the long-term survival.

Syfte: Syftet var att finna skillnader och samband i self-efficacy (SE) – med avseende på typ av artroplastik, kön och ålder – inför två förflyttningar. Detta för att se vilka patienter som kan vara i större behov av att stärka SE postoperativt. Metod: Studien gjordes på inneliggande patienter som genomgått en höft- eller knäartroplastik. Ett för undersökningen framställt frågeformulär undersökte de 117 deltagarnas SE inför att sätta sig upp på sängkanten samt gå med hjälpmedel. Deltagarna skattade SE inför förflyttningarna första eller andra dagen efter operationen. Resultat: Deltagare som hade genomgått en knäartroplastik skattade signifikant högre SE inför att sätta sig upp på sängkanten än de som hade genomgått en höftartroplastik. Männen skattade signifikant högre SE inför båda momenten jämfört med kvinnorna. Det fanns en låg korrelation mellan stigande ålder och låg SE inför att gå med hjälpmedel. Konklusion: Resultaten tyder på att SE inför förflyttningarna skiljer sig mellan patienter. Detta bör behandlande sjukvårdspersonal ta hänsyn till i ett postoperativt skede för att undvika immobiliseringskomplikationer hos patienterna.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2009.

Thesis (Ph.D.)--University of Florida, 2004. / Typescript. Title from title page of source document. Document formatted into pages; contains 102 pages. Includes Vita. Includes bibliographical references.