Bone Morphogenetic Protein 2 (BMP2) is a growth factor needed to initiate fracture repair and is involved in the differentiation of progenitor cells to the osteochondral lineage. Osteogenesis and angiogenesis are coupled processes, however the mechanism by which these processes are coupled and the role that BMP2 plays in coupling these processes is not well understood. In distraction osteogenesis, a bone regeneration model mediated by mechanical distraction of an osteotomy, BMP2 expression was primarily associated with blood vessels. Therefore, transgenic mice were used to conditionally delete BMP2 expression (BMP2-cKO) in smooth muscle cells during distraction osteogenesis to identify the role of BMP2 in osteogenesis and angiogenesis. Vessel formation was characterized by vascular perfusion of animals with a barium-gelatin solution, which was used as a radiographic contrast agent that allowed vessel formation to be quantified by micro-computer assisted tomography (µCT). Using the same transgenic mice to label those cells in which BMP2 had been deleted, histological analysis was performed to confirm the targeting specificity of the BMP2-cKO. µCT analysis showed less bone formation occurred in the BMP2-cKO animals compared to controls. The µCT analysis further showed vessel volume and thickness were decreased in BMP2-cKO animals at both day 17 and 31, suggesting that there is a relationship between BMP2 and vessel size. Vessel number was greater in controls than the BMP2-cKO animals at day 17, however the BMP2-cKO animals had a larger vessel number than the number by day 31. Histological analysis confirmed knockout of BMP2 expression in smooth muscle cells, as well as in skeletal muscle and chondrocytes. These results suggest the importance of BMP2, not only in bone formation, but also in vessel morphogenesis.

Orientador: João Batista de Miranda / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-19T22:32:06Z (GMT). No. of bitstreams: 1 Yamada_NeideSumie_M.pdf: 1286859 bytes, checksum: 13049b157f58cc99cc1277c8a5174f29 (MD5) Previous issue date: 2012 / Resumo: Introdução: As infecções são uma das complicações mais temidas nas artroplastias de quadril e joelho. A falta de um registro nacional de artroplastias e a escassez de publicações nacionais sobre o tema leva ao desconhecimento sobre os fatores de risco desta complicação na população brasileira. Objetivo: O objetivo deste trabalho é identificar a incidência e os fatores de risco para infecções relacionadas com as artroplastias de quadril (PTQ) e joelho (PTJ) em pacientes do hospital das clínicas da Unicamp. Métodos: Foi realizado um estudo tipo caso-controle, retrospectivo, das PTQs e PTJs feitas no período de 2005 a 2009, onde foi revisado os prontuários e coletados estes dados: idade, sexo, peso, altura,tipo de cirurgia, tempo de duração da cirurgia, número de doses de antibioticoterapia profilática, tempo de internação pré e pós-operatório, tempo de sondagem vesical de demora, presença de comorbidades como hipertensão e diabetes, história de etilismo e tabagismo, infecções recentes e tardias. Resultados: Foram incluídas neste estudo 173 artroplastias, sendo 109 (63%) de quadril e 64 (37%) de joelho. A incidência de infecções nas PTQs foi de 6,4% e nas PTJs foi de 20,3%. Dentre os fatores de risco para infecção, os que tiveram correlação positiva foram o maior tempo de internação pós-operatório e o maior tempo total de internação. Conclusão: A incidência de infecções em prótese total de joelho e quadril foi considerada alta, acima da estabelecida na literatura. Os únicos fatores de risco que apresentaram correlação foram o tempo de internação pós- operatória e o tempo total de internação / Abstract: Introduction: Infections are one of the most challenging drawbacks in hip and knee Arthroplasty surgery. The lack of a national databank and the shortage of national paper about this issue, cause risk factors unknown among Brazilian people. Objective: To identitify incidence and risk factors ofinfection related to hip and knee Arthroplasty surgery, in a Brazilian teaching hospital. Method: A retrospective case-control study was performed between 2005 and 2009, to evaluate medical records of patients submitted to hip or knee Arthroplasty. Data collected was the following: age, gender, weight, heitght, kind of surgery, surgery duration, antibiotic drug doses number, hospitalization length, urinary catheter length, medical conditions (such diabetes, high bloodo pressure, smoking, drinking), acute and chronic infections. Results: It was included 173 patients, of which 109 (63%) were total hip arthroplasties and 64 (37%) were total knee arthroplasties. Hip arthrplasty infection rate was 6,4%, and Knee Arthroplasty infection rate was 20,3%. Among infection risk factors, total length of hospital stay and length of post-surgical hospital stay were the that presented significant correlation. Conclusion: Infection rates after hip and knee arthroplasties were considered high. The only risk factors that presented a significant correlation were total hospital stay length and post-surgical hospital stay length / Mestrado / Fisiopatologia Cirúrgica / Mestre em Ciências da Cirurgia

No description available.

Osteoarthritis develops secondary to the action of hostile biomechanics upon susceptible cartilage. Cam morphology describes a loss of concavity at the femoral head-neck junction resulting in femoral impaction against the acetabular rim within a functional range of movement. This impaction is termed femoroacetabular impingement and can result in pain and cause damage to adjacent articular cartilage that progresses to osteoarthritis. Cam morphology is a target for joint preservation strategies. The first study in this thesis compares hip development in academy football players with controls from local schools. The results provide strong evidence that cam morphology can develop in response to intense sporting activity during adolescence. At present, it is not possible to recommend activity modification as the cardiovascular benefits of exercise are likely to outweigh potentially detrimental effects on hip morphology. Nevertheless, individuals participating in high-level sports during youth may represent a high risk cohort for osteoarthritis warranting surveillance. Diagnostic tools currently available only allow identification of late joint degeneration when disease is irreversible. Advances in the field of disease biomarkers may overcome this challenge. The second study of this thesis explored the prognostic value of compositional MRI. Baseline delayed gadolinium-enhanced MRI of cartilage was able to predict the development of radiographic hip osteoarthritis in asymptomatic individuals within five years. As well as identifying individuals who are likely to benefit from intervention, compositional MRI may allow the evaluation of treatment efficacy within short timeframes. A number of interventions aimed at joint preservation are under investigation for treating cam morphology femoroacetabular impingement. Arthroscopic surgery is increasingly performed to restore the concavity at the femoral head-neck junction and prevent impaction against the acetabular rim. A feasibility study was performed for a proposed randomised controlled study comparing operative and non-operative treatment. The study protocol was developed for the 'Femoroacetabular Impingement Trial' (FAIT).

Surgical interventions on the hip joint have greatly increased over the past decade, with the cumulative cost total hip arthroplasties (THA) alone exceeding $400B/year by 2020. Although positive patient-reported outcomes and satisfaction after THA and hip preservation for cam femoroacetabular impingement (FAI) are among the highest in orthopaedics, a limited number of research has investigated the biomechanics of dynamic activities following-up the surgery. This doctoral thesis examined the kinematics, muscle force component, and hip contact loading in pre- and postoperative patients during the deep squat motion. Specifically, this research: 1) examined muscle strength and pelvic kinematics in asymptomatic FAI, 2) examined lower-limb kinematics and muscle activity in postoperative patients who underwent either THA or FAI correction during a deep squat task, and 3) examined muscle force contributions and hip contact forces (HCF) during dynamic motion in postoperative FAI patients. First, clinical and medical imaging evaluations classified the participants into three groups: symptomatic FAI, asymptomatic FAI (FAD – participants had the cam deformity, but no pain), and healthy controls. The FAD participants had significantly greater hip extensor strength compared to the FAI and CTRL groups, which allowed them to achieve greater pelvic mobility and squat as deep as the CTRL group. Second, at the follow-up for the FAI surgery the patients showed increased pelvic ROM during the squat, and weakness associated with hip flexion and hip flexion-with-abduction were associated with postoperative alterations. For the THA follow-up analyses, the patients using a dual- mobility (DM) prosthesis reached an anterior pelvic tilt similarly to the CTRL during the dynamic parts of the squat; however, without returning its neutral tilt at the bottom of the squat, while the single- bearing (SB) prosthesis was associated with excessive hip abduction during the squat. Third, a generic full-body musculoskeletal model (MSKM) was optimized to allow for the analysis of tasks with a high range of motion (ROM; e.g. deep squat task), which controlled muscle moment arms during the high joint flexions to avoid the model’s motor tendon units (MTU) to penetrate the bony structures and respect the anatomical via points. Simulation performed during gait demonstrated that FAI patients enhance medial-lateral hip stability postoperatively, allowing reduced dynamic forces of the muscles associated with the sagittal aspect of the gait due to a less compensatory strategy to stabilize the hip joint. Furthermore, simulations performed during deep squat showed a higher anterior pelvic tilt in postoperative FAI patients as a ‘restore to native’ mechanism once the cam-deformity was no longer present. Increased semimembranosus force was linked to higher vertical HCF and total magnitude. The outcomes of this research include findings for gait and squat analyses that provide a better understanding of the pelvic mobility and hip muscle forces in hip diseases. In silico models can improve biomechanical assessment of postoperative patients in order to quantify surgical effectiveness and support clinicians in making subject-specific case decisions. The contributions also lay on the assertion of helping us to formulate future research directions in biomechanics applied to the orthopaedics field.

Bakgrund: Livsstilssjukdomar som diabetes och hjärt- och kärlsjukdomar ökar i samhället vilket medför en ökad risk för komplikationer. I västvärlden är diabetes och ateroskleros den vanligaste orsaken till amputation. Sjuksköterskans roll i samband med en amputation är att stötta patienten i utmaningarna som kan uppkomma och ge möjlighet till god återhämtning. Välbefinnande är en individuell upplevelse och som begrepp flerdimensionellt. Syfte: Studiens syfte är att belysa vuxna personers upplevelser av välbefinnande efter en amputation av extremitet orsakad av kärlinsufficiens. Metod: Studiedesignen är en litteraturstudie med kvalitativ induktiv ansats. Databassökningen gjordes i CINAHL och PubMed. Totalt inkluderades 12 vetenskapliga artiklar som analyserades i tre steg inspirerad av innehållsanalys. Resultat: I analysen skapades tre kategorier: Välbefinnandets påverkan av psykologiska omständigheter, Omgivningens påverkan på välbefinnande, Ambivalens & avgörande. Välbefinnandets påverkan av psykologiska omständigheter beskriver att självbilden och självständigheten förändrades efter en amputation, och hur amputationen påverkade deras psykiska hälsa. Omgivningens påverkan på välbefinnande skildrar vilken roll familj, närstående och vårdpersonal hade för individens välbefinnande. Ambivalens & avgörande beskriver hur personerna såg tillbaka på sitt beslut om amputation och tankar på framtiden. Under kategorierna återfinns totalt sju underkategorier. Konklusion: Amputation var en stor omställning på personen och hade en påverkan på välbefinnandet, såväl positivt som negativt. Upplevelsen av välbefinnande efter en amputation och vilka faktorer som ger välbefinnande är individuellt därav är personcentrerad omvårdnad av betydelse.

<p>  </p> <p>Articular cartilage is a strong but flexible connective tissue that covers and protects the ends of long bones. Osteoarthritis (OA) is a degenerative joint disease which is the most prevalent type of arthritis. The progression and development of OA involves changes in cartilage composition and tissue degradation. As a result, the biomechanical and biotribological properties of the joint may be affected. It has not been determined how cartilage composition and mechanical properties affect its wear and friction, or if there are feasible strategies to improve cartilage performance.</p> <p>Photochemical crosslinking is one method to enhance the modulus and strength of collagenous tissues and improve their resistance to enzymatic degradation. In chapter 2, the effect of photochemical crosslinking on viscoelastic properties of cartilage using an indentation test were investigated. Results of the study indicated that chloro-aluminum pthalocyanine tetrasulfonic acid (CASPc) photo-initiator and 670 nm light increases the modulus of articular cartilage, though this effect is likely limited to the tissue surface.</p> <p>The objective of research described in chapter 3 was to assess correlations between tissue composition and modulus with friction and wear properties in healthy cartilage specimens. Viscoelastic properties of cartilage were obtained via indentation and then the coefficient of friction was measured during an accelerated <em>in vitro</em> wear test. The composition of adjacent cartilage tissue including collagen, glycosaminoglycans, and pyridinoline crosslinks were obtained by biochemical assays. Correlation analysis suggested that stiffer cartilage with higher glycosaminoglycans (GAGs) and collagen content leads to higher wear resistance of the cartilage. Enzymatic collagen crosslinks in type II collagen, pyridinoline (PYD), also enhances the wear resistance of the collagen network. The three parameters of wear, composition, and mechanical properties of cartilage were interrelated and were all correlated with one another. However, friction was independent of these in healthy cartilage tissue. </p> <p>In chapter 4, the hypothesis that mechanical wear is exacerbated in degraded cartilage tissue was tested. Fresh osteochondral specimens were treated with interleukin-1β, with chondroitinase ABC (ChABC) to specifically remove GAGs, or with collagenase to degrade the collagen network during culture. Viscoelastic properties of the tissues were characterized followed by an accelerated <em>in vitro</em> wear test. Results of this study suggest that although the degradation of cartilage was observed with exposure to IL-1β, ChABC and collagenase, wear was not uniform between the three. All three treatments lost GAGs across their superficial zone, and tissue loss due to wear appeared to be confined to the superficial zone. The passive loss of GAGs did not induce increased wear of the tissue. However, an increase in wear was observed with degradation of the collagen network. As the COF was not affected by the degradative treatments, the changes in wear were attributed to alterations in tissue structure and composition</p> <p>Finally, in chapter 5, conclusions, and summary of all main three chapters were stated and directions for future studies were presented.  </p>

No description available.

Thesis (M.Tech.: Radiography) - Dept. of Radiography, Durban University of Technology, 2006 xxiv, 214 leaves, Annexures A-L / The aim of this research was to determine normal bone mineral density (BMD) reference ranges (means and standard deviations) for the lumbar spine, total hip and distal forearm, for Indian women of varying age groups in KwaZulu-Natal. The aim also included a comparison of the study population reference ranges with those provided by the manufacturer in order to evaluate any diagnostic implications.

Hip fracture is a global and a growing public health problem. More women than men sustain hip fractures, the incidence increases exponentially with age and mean age is above 80. About one third of hip-fracture patients suffer from dementia and are prone to develop acute confusional state (delirium). Delirium is one of the most common complications after hip-fracture surgery, and seriously impacts on morbidity and mortality. Malnutrition is also common in hip-fracture patients and is associated with postoperative complications, such as delayed healing of the wound, infections and decubitus ulcers. Arthroplasty is usually preferred procedure in displaced femoral neck fractures but is, however, controversial in patients with dementia due to the fear of dislocation of the prosthesis. The aims of this thesis are to identify risk factors for delirium and the impact of delirium on rehabilitation outcome, to evaluate whether a postoperative multi-factorial intervention program could reduce delirium, to investigate the effect of a nutritional intervention and to evaluate complications, functional outcome and mortality regarding two surgical methods, hemiarthroplasty (HAP) and internal fixation (IF), in old patients with femoral neck fracture. Thirty-eight out of 61 consecutive patients (62%) were delirious on admission to hospital or developed postoperative delirium. An increased risk of postoperative delirium was found among hip-fracture patients with dementia and/or depression. Delirious patients were hospitalized longer, were more dependent in their activities of daily living, had poorer psychological well-being and suffered more complications than non-delirious patients. A postoperative multi-factorial and multidisciplinary intervention program reduced the incidence, at 55% vs 75% (p=0.003), and number of days with delirium, 5 vs 10 days (p=0.009). Postoperative complications were also reduced; decubitus ulcers 9% vs 22% (p= 0.010), urinary tract infections 31% vs 51% (p=0.005), falls 12% vs 27% (p=0.007), and the mean hospitalization period was 10 days shorter in the intervention group (p=0.030). Malnutrition was common among all these patients (53 %) and associated with postoperative complications such as decubitus ulcers and delirium. However, the nutritional intervention had no effect on nutritional parameters at four months, nevertheless men had better nutritional outcomes than women. A higher proportion of patients with dementia operated on using HAP had regained their pre-fracture ability to walk independently at the one-year follow up compared with those operated on using IF. Six of 83 patients dislocated their HAP during hospitalization and during an episode of delirium, none had dementia. No difference in mortality between the surgical methods was seen. Dementia per se should not be a reason to disqualify patients from being treated with the most appropriate surgical method. It is clinically important to discriminate between dementia and delirium, since delirium can be prevented and treated even in patients with dementia. Old patients undergoing surgery have special needs that are not always catered for in ordinary orthopaedic or surgical wards. The special care for these patients should include: a combined nursing and medical care based on comprehensive geriatric assessments, systematic prevention, detection and treatment of postoperative complications such as delirium, hypoxemia, urinary tract infections, pain, malnutrition and an active rehabilitation. It is obvious that improved quality of care reduces patient suffering and seemingly the costs for society.