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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
391

Customization of knee implants and optimizations of bone-implant interface

Harrysson, Ola Lars Anders 01 October 2001 (has links)
No description available.
392

Assessment of Pre-Operative Functional Differences in Patients Undergoing Total and Partial Knee Arthroplasties

Gafoor, Fatima January 2024 (has links)
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)
393

A double-blinded, placebo controlled clinical trial evaluating the efficacy of the Harpago and celery seed cream in mild to moderate degenerative joint disease of the knee

Pillay, Desigan January 2006 (has links)
Thesis (M.Tech.:Chiropractic) - Dept. of Chiropractic, Durban Institute of Technology, 2006 xvi, 82 leaves, Annexures A-L / To determine the efficacy of the Harpago and celery seed cream in mild to moderate degenerative joint disease of the knee in terms of subjective and objective clinical findings
394

A prospective clinical trial to determine the relative effectiveness of cross friction massage versus Graston instrument assisted soft tissue mobilisation in treating patellar tendinopathy

Fraser, Donna Francoise January 2008 (has links)
Dissertation submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, 2008. / There are mechanical loads applied to the patella tendon in almost all sporting activities and as a result is commonly injured (Peterson and Renström, 2003:321). Patellar tendinopathy is a common chronic tendinopathy (Hamilton and Purdman, 2004) and occurs commonly in athletes who impose rapid eccentric loading of the knee extensor mechanism (Norris, 2004:246). Deep Transverse Friction Massage (DTFM) and soft tissue mobilization are the two most common forms of manual therapy used to treat patellar tendinopathy (Rees et al., 2006). DTFM is considered the most effective treatment for patellar tendinopathy (Brunker and Khan, 2002:487). It is theorised that DTFM causes the softening of scar tissue and the breakdown of adhesions, promoting the realignment of disrupted connective tissue fibrils within the affected tendon (Stasinopoulos and Johnson, 2007). Graston Instrument Assisted Soft Tissue Mobilization (GIASTM) consists of a set of stainless steel instruments (Carey 2003:2) and is an advanced form of soft tissue mobilization used in detecting and releasing scar tissue, adhesions and fascial restrictions (Carey, 2003:7). The controlled microtrauma created by these instruments is hypothesised to create a localised inflammatory response (Hammer, 2004) in a similar mechanism to that of DTFM. The aim of this study was to determine the relative effectiveness of GIASTM versus DTFM in treating patellar tendinopathy. The study included a total of twenty-six knees among twenty-one patients. Patients were placed randomly into either the GIASTM group or the DTFM group. Each patient received a total of twelve treatments over a three month period. Algometer and inclinometer readings were recorded at set intervals and compromised objective measures. Two questionnaires and a numerical pain rating scale (NRS) were administered at set intervals and compromised subjective measures. SPSS version 13.0 (SPSS Inc., Chicago, Illinois, USA) was used to analyse the data. Repeated measures ANOVA was used to examine changes in quantitative outcomes over the time points (intragroup analysis) and a treatment effect (intergroup analysis). To control for the partial pairing in the intergroup analysis, a variable which classified each subject as paired (both left and right knee used in study) or non-paired (only used once in study) was used as a factor in the model. Correlations between the intragroup changes in the various outcome variables were assessed using Pearson’s correlation coefficients. Statistical analysis of both objective and subjective data revealed significant improvements for most outcome measures in the study. Findings imply that GIASTM is as effective as DTFM in treating patellar tendinopathy.
395

Determining femoral component goodness-of-fit using computer segmentation and numerical simulation

Van Schalkwyk, Etienne P. 03 1900 (has links)
Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The c2 goodness-of-fit (GOF) test was used to determine which standard femoral component would achieve the best geometrical fit for a specific patient. This was done by creating 3D models from computerized tomography scan data through computer segmentation using Materialise MIMICS. The second step was to measure the morphological dimensions of the distal femur whereof twelve were selected and compared to the dimensions of two commercial femoral prosthesis designs. Thirdly, cadaveric femurs were scanned with a 3D desktop scanner to create a database with the dimensions of healthy knees. The 3D model database of the cadaveric femurs included cartilage layer. A cartilage thickness was added to the CT knee dimensions using a self-organizing map (SOM) calculation based on the healthy knee database. The developed method calculated alignment angles with higher accuracy than presently used and determined preoperatively which size to implant. Kinematic simulations of total knee arthroplasty (TKA) knees were compared to normal knee simulations created in LifeMOD. The articulating surface was the only variable changed between the two simulations and the kinematics of different sizes were evaluated. A method was created to scale the femoral component using the standard available sizes. The completed project will be used as foundation for customization of TKA prostheses. / AFRIKAANSE OPSOMMING: Die c2 graad van passing toets metode was gebruik om te bereken watter standaard femorale komponent ’n patiënt die beste geometries pas. Dit was gedoen deur eerstens 3D modelle gemaak vanaf CT skandeer data deur rekenaar segmentasie met Materialise MIMICS. Daarna was morfologiese dimensies gemeet vanaf die distale femur, waarvan twaalf gekies en vergelyk was teen two kommersiële femorale prostesis ontwerpe. Laastens was kadawer femurs geskandeer met ‘n 3D skandeerder om ’n databasis van gesonde knieë te maak. Die 3D modelle van die kadawer bene het die kraakbeen laag bevat. Die kraakbeen dikte was by die CT knie dimensies gevoeg d.m.v. SOM en die gesonde knie databasis. Die nuwe metode bereken die belynings hoeke met hoër akkuraatheid as wat huidiglik gebruik word en bereken voor die operasie watter grote om te gebruik. Kinematiese simulasies van knie prostesis was vergelyk met ’n normale knie simulasies gemaak in LifeMOD. Die artikulêre oppervlakte was die enigste veranderlike tussen die twee simulasies en kinematika van verskillende grotes was ondersoek. ‘n Metode was geskep om die standaard femorale komponent se skaal te verander vir ’n beter passing.
396

Early knee arthritis : symptoms and structure

Jones, Luke D. January 2013 (has links)
Knee osteoarthritis (OA) is the commonest form of lower limb OA with a lifetime risk of over 40%. It is a disease characterised by symptoms such as pain and loss of function. In addition there are typical structural features on both radiographs and MRI. Knee OA represents a spectrum of disease, ranging from early preclinical cartilage change to established full thickness disease. Anteromedial knee OA is a particular phenotype of knee OA where disease is confined to the medial compartment. Whilst end stage arthritis is treated reliably with joint arthroplasty, those with early stage disease are treated with a variety of non- surgical interventions with varying success. This thesis is concerned with understanding the disease of patients that have early radiographic changes but symptoms not controlled by conservative measures. Up to 150 of these patients a year present to the Nuffield Orthopaedic Centre, Oxford. They have been described as being in the “Treatment Gap”. A series of validation studies were performed to determine the optimal method for diagnosing cartilage defects within the knee. The three commonest diagnostic methods were examined for their validity. Arthroscopic assessments of cartilage lesions demonstrated a moderate level of intra and inter observer reliability. In contrast, radiographs and MRI demonstrated high levels of reliability. When using MRI as a criterion standard, both radiographs and arthroscopic assessment were found to have poor accuracy. Based on the work in this thesis a formal definition of the cartilage changes exhibited in early knee OA was proposed. A cross sectional cohort of 100 patients with the symptoms and radiological features of early knee OA were identified. Their pain and function profile was compared to two comparison groups of patients at the end stage of knee OA (defined by the need for partial or total arthroplasty). In up to 78% of individual cases those with early OA had pain and function profiles as bad as those with end stage disease. The cross sectional symptoms of early knee OA demonstrate a marked discordance with their mild radiographic changes. The same cohort was extended to 125 patients. They were followed over one year with monthly PROM assessments to determine how symptoms change over time. 43% of patients experience a clinical improvement over 12 months, 31% experience a clinical deterioration and 26% remain unchanged. The range in OKS variation over 12 months was on average 12 points, with clinically relevant variation occurring on 45% of monthly measurements. Patients with early knee OA can expect to experience considerable variation in their symptoms over 12 months and this must be considered when planning interventions. A number of patients with early knee OA were noticed to demonstrate medial meniscal extrusion. Using data from the Osteo Arthritis Initiative (OAI) a nested case control study was designed to determine how the presence of meniscal extrusion in an otherwise normal knee affects the risk of developing knee OA over the next 48 months. This demonstrated an Odds Ratio of 3.5, suggesting that meniscal extrusion is a considerable risk factor for the development of OA. The presence of a knee injury or operative intervention to the index meniscus was shown to increase this risk. Many phenotypes of OA are known to demonstrate familial aggregation. In an attempt to determine where the earliest structural changes occur in medial compartment knee OA, a cohort of patients selected only for their family history of the disease were developed. This cohort was compared to spouse controls for the presence of knee OA, as well as meniscal extrusion and long leg alignment. In addition, a functional analysis of their cartilage was performed. This cohort was not shown to be at increased risk of disease compared to controls. Discussion of the possible reasons for this finding is presented. Early knee osteoarthritis is a considerable clinical problem. This thesis has aided the understanding of the condition by firstly defining the radiological description of these patients. Secondly, their cross sectional and longitudinal symptom profile have been described for the first time. In addition, the presence of an extruded meniscus has been demonstrated as a substantial risk factor for the disease. Finally, family history has not been demonstrated as a risk factor for the disease within the limits of the study described here. Future work has been proposed.
397

The biomechanical risk factors associated with preventing and managing iliotibial band syndrome in runners : a systematic review

Aderem, Jodi 04 1900 (has links)
Thesis (MScPhysio)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Introduction: Iliotibial band syndrome (ITBS), an overuse injury, is the second most common running injury and the main cause of lateral knee pain in runners. Due to the increasing number of runners worldwide there has been an increase in its occurrence. Runners with ITBS typically experience symptoms just after heel strike at approximately 20°-30° of knee flexion (impingement zone) during the stance phase of running. A variety of intrinsic and extrinsic risk factors may be responsible for why some runners are more prone to developing symptoms during the impingement zone as opposed to others. Abnormalities in running biomechanics is an intrinsic risk factor which has been most extensively described in literature but little is known about its exact relationship to ITBS. Objectives: The purpose of this systematic review was to provide an up to date evidence synthesis of the biomechanical risk factors associated with ITBS. These risk factors may need to be considered in the prevention or management of ITBS in runners. A clinical algorithm is also presented. Methods: A systematic review with meta-analysis was conducted. An electronic search was performed in PubMed, PEDro, SPORTSDisc and Scopus of literature published up-until May 2014. Cross-sectional and cohort studies were eligible for inclusion if they evaluated the lower limb biomechanics of runners with ITBS or those who went onto developing it. All studies included in the review were methodologically appraised. Evidence was graded according to the level of evidence, consistency of evidence and the clinical impact. Data was described narratively using tables or narrative summaries where appropriate. A meta-analysis was conducted for biomechanical risk factors which were reported in at least two studies, provided that homogeneity in the outcomes and samples were present. Results: A total of 11 studies were included (1 prospective and 10 cross-sectional). Overall the methodological score of the studies was moderate. Increased peak hip adduction and knee internal rotation during the stance phase may predict the development of ITBS in female runners. These biomechanical risk factors may need to be screened for ITBS prevention, despite the evidence base being limited to a single study. Currently there is no conclusive evidence that any of the biomechanical parameters need to be considered when managing runners with ITBS. Stellenbosch University https://scholar.sun.ac.za iii Conclusion: Biomechanical differences may exist between runners with ITBS and those who may develop ITBS compared to healthy runners. Although a large variety of biomechanical risk factors were evaluated, the evidence base for screening or managing these risk factors for runners with ITBS is limited. This is due to a small evidence base, small clinical effect and heterogeneity between study outcomes and findings. Further prospective and cross-sectional research is required to ascertain if abnormalities in running biomechanics may be related to why runners develop ITBS or to ascertain which risk factors may be involved when managing these runners. / AFRIKAANSE OPSOMMING: Inleiding: Iliotibiale-band-sindroom (ITBS), ’n besering vanweë oormatige gebruik, is die tweede algemeenste hardloopbesering en die hoofoorsaak van laterale kniepyn by hardlopers. Namate die getal hardlopers wêreldwyd toeneem, neem die voorkoms van hierdie toestand ook toe. Hardlopers met ITBS ervaar tipies simptome ná die hakslag met die knie ongeveer 20-30° gebuig (die wrywingsone of “impingement zone”) gedurende die staanfase van hardloop. Verskeie intrinsieke en ekstrinsieke risikofaktore kan ’n rol speel in waarom sommige hardlopers meer geneig is as ander om gedurende die wrywingsone simptome te ervaar. Abnormaliteite in hardloopbiomeganika is ’n intrinsieke risikofaktor wat reeds omvattend in die literatuur beskryf is. Tog is weinig bekend oor presies hoe dit met ITBS verband hou. Oogmerke: Die doel van hierdie stelselmatige ondersoek was om ’n sintese te bied van die jongste bewyse van die biomeganiese risikofaktore van ITBS. Hierdie risikofaktore kan dalk oorweeg word om ITBS by hardlopers te voorkom of te bestuur. ’n Kliniese algoritme word ook aangebied. Metodes: ’n Stelselmatige ondersoek is met behulp van meta-ontleding onderneem. PubMed, PEDro, SPORTSDisc en Scopus is elektronies deurgesoek vir literatuur wat tot en met Mei 2014 verskyn het. Deursnee en kohortstudies is ingesluit indien dit gehandel het oor die biomeganika in die onderste ledemate van hardlopers wat ITBS het of later ontwikkel het. Alle studies wat deel was van die ondersoek is metodologies geëvalueer. Bewyse is aan die hand van bewysvlak, bewyskonsekwentheid en kliniese impak beoordeel. Data is narratief beskryf met behulp van tabelle of narratiewe opsommings waar dit toepaslik was. ’n Meta-ontleding is onderneem waar biomeganiese risikofaktore in minstens twee studies aangemeld is, mits daar homogeniteit in die uitkomste sowel as die steekproewe was. Resultate: Altesaam 11 studies is ingesluit (een prospektief en tien deursnee). Die metodologiese telling van die studies was oorwegend gemiddeld. Verhoogde spitsheupadduksie en interne knierotasie gedurende die staanfase kan op die ontwikkeling van ITBS by vrouehardlopers dui. Hierdie biomeganiese risikofaktore kan dalk nagegaan word vir ITBS-voorkoming, al was die bewysbasis beperk tot ’n enkele studie. Daar is tans geen afdoende bewys dat enige van die biomeganiese parameters oorweeg behoort te word in die bestuur van langafstandatlete met ITBS nie. Gevolgtrekking: Daar bestaan dalk biomeganiese verskille tussen hardlopers wat ITBS het of kan ontwikkel en gesonde hardlopers. Hoewel ’n groot verskeidenheid biomeganiese risikofaktore beoordeel is, is die bewysbasis vir die toets of bestuur daarvan by atlete met ITBS beperk. Dít is vanweë die klein hoeveelheid bewyse, die klein kliniese impak, en heterogeniteit tussen studie-uitkomste en bevindinge. Verdere prospektiewe en deursneenavorsing word vereis om te bepaal of abnormaliteite in hardloopbiomeganika ’n rol kan speel in waarom langafstandhardlopers ITBS ontwikkel, of om vas te stel watter risikofaktore ter sprake kan wees in die bestuur van hierdie hardlopers.
398

The effect of fatigue protocols on knee control during functional activities

Pretorius, Jaco 04 1900 (has links)
Thesis (MScPhysio)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Introduction ACL injuries are among the most serious injuries that professional and amateur sports men and women sustain. More than 120 000 ACL injuries occur annually in the USA alone. The highest incidence of ACL injuries are seen in multi-directional and multi-factorial sports such as soccer, basketball, lacrosse, American football, rugby and Australian rules football. It is hoped that the proposed review will clarify issues relating to the effect of fatigue on knee control, as it will focus on multiple movements found in different sporting codes. By including both studies on healthy adults as well as subjects who have sustained ACL injuries, a clearer picture can be formed on the global effect of fatigue on knee control. Objective The objective of this review was to identify, collate and analyse the current evidence on the effect of fatigue protocols on knee control during functional tasks, such as side-stepping, bilateral jumping/landing and crossover-cutting. Methodology A comprehensive search of electronic databases was conducted between April 2013 and August 2013 (updated in April 2014) for eligible articles for inclusion in the review. Methodological quality was assessed using a modified Downs and Black checklist. Results Ten studies met the eligibility criteria and were included in the review. The included studies reported a wide variety of fatigue protocols. Several different test movements were utilised in the studies. The test movements included cutting movements, drop jumps, stop jumps, vertical jumps, bilateral drop landing and rotational movements. The overall results indicated that fatigue had a negative impact on knee control. There were however studies which reported conflicting results. Gender differences were also highlighted in the results of included studies where it became evident that females tend to be more susceptible to knee injuries due to altered kinematics as a result of fatigue. Conclusion Fatigue generally seems to affect knee control negatively across various fatigue protocols. Future research should investigate using a standardised fatigue protocol to achieve more accurate and consistent results during the different functional activities. / AFRIKAANSE OPSOMMING: Nie beskikbaar
399

To compare proprioceptive performance and quality of life among patients after total knee arthroplasty, unicondylar knee arthroplasty,osteoarthritic knee and normal individuals in Chinese ethnic group inHong Kong

Cheng, Sze-chung., 鄭思宗. January 2004 (has links)
published_or_final_version / Medical Sciences / Master / Master of Medical Sciences
400

CHANGES IN LONGITUDINALLY ASSESSED BIOMECHANICAL PARAMETERS RELATED TO INCREASED RISK OF ANTERIOR CRUCIATE LIGAMENT (ACL) INJURIES IN ADOLESCENT FEMALE AND MALE ATHLETES

Ford, Kevin Ray 01 January 2009 (has links)
Females suffer anterior cruciate ligament (ACL) injuries at a 2 to 10-fold greater rate compared to male athletes participating in similar sports. Altered movement patterns and inadequate knee stiffness are two interrelated factors that may increase ACL injury risk. Onset of these neuromuscular risk factors may coincide with the rapid adolescent growth that results in the divergence of a multitude of neuromuscular parameters between sexes. The overall purpose of this dissertation was to determine if neuromuscular ACL injury risk factors in female athletes increase following rapid growth and development compared to males. Male and female athletes were tested with three-dimensional motion analysis techniques during a drop vertical jump over two consecutive years to determine if ACL injury risk factors increased. Pubertal females showed a significant longitudinal increase in knee abduction angle compared to post-pubertal females and both male groups. The increase in knee abduction angle appeared to remain consistent, as the post pubertal female cohort had greater overall knee abduction compared to post-pubertal males. Similar results were found with a greater magnitude of knee abduction moment in post-pubertal females compared to males. Males and females increased ankle, knee and hip active stiffness from the first to second year of testing. Ankle and hip stiffness were increased significantly more in the pubertal group compared to post-pubertal. Sex and maturational group differences were found in hip and ankle joint stiffness. Post-pubertal males had significantly greater hip stiffness than the other groups (even when normalized to body mass). This indicates that post-pubertal males utilized a different neuromuscular strategy during landing. Males had a significantly greater increase from year to year in vertical jump height compared to females. Vertical jump height is often related to a measure of whole body power and indicates that males had a significant neuromuscular spurt compared to females. Early puberty appears to be a critical phase related to the divergence of increased ACL injury risk factors. Injury prevention programs that focus on neuromuscular training may be beneficial to help address the development of ACL injury risk factors that occur in female athletes during maturation.

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