RESUMO
BACKGROUND: With massive investment in health-related research, above and beyond investments in the management and delivery of healthcare and public health services, there has been increasing focus on the impact of health research to explore and explain the consequences of these investments and inform strategic planning. Relevance is reflected by increased attention to the usability and impact of health research, with research funders increasingly engaging in relevance assessment as an input to decision processes. Yet, it is unclear whether relevance is a synonym for or predictor of impact, a necessary condition or stage in achieving it, or a distinct aim of the research enterprise. The main aim of this paper is to improve our understanding of research relevance, with specific objectives to (1) unpack research relevance from both theoretical and practical perspectives, and (2) outline key considerations for its assessment. APPROACH: Our approach involved the scholarly strategy of review and reflection. We prepared a draft paper based on an exploratory review of literature from various fields, and gained from detailed and insightful analysis and critique at a roundtable discussion with a group of key health research stakeholders. We also solicited review and feedback from a small sample of expert reviewers. CONCLUSIONS: Research relevance seems increasingly important in justifying research investments and guiding strategic research planning. However, consideration of relevance has been largely tacit in the health research community, often depending on unexplained interpretations of value, fit and potential for impact. While research relevance seems a necessary condition for impact - a process or component of efforts to make rigorous research usable - ultimately, relevance stands apart from research impact. Careful and explicit consideration of research relevance is vital to gauge the overall value and impact of a wide range of individual and collective research efforts and investments. To improve understanding, this paper outlines four key considerations, including how research relevance assessments (1) orientate to, capture and compare research versus non-research sources, (2) consider both instrumental versus non-instrumental uses of research, (3) accommodate dynamic temporal-shifting perspectives on research, and (4) align with an intersubjective understanding of relevance.
Assuntos
Pesquisa Biomédica/tendências , Necessidades e Demandas de Serviços de Saúde , Pesquisa sobre Serviços de Saúde/tendências , Previsões , HumanosRESUMO
BACKGROUND: Although the option of next available surgeon can be found on surgeon referral forms for total joint replacement surgery, its selection varies across surgical practices. OBJECTIVES: Objectives are to assess the determinants of (a) a patient's request for a particular surgeon; and (b) the actual referral to a specific versus the next available surgeon. METHODS: Questionnaires were mailed to 306 consecutive patients referred to orthopedic surgeons. We assessed quality of life (Oxford Hip and Knee scores, Short Form-12, EuroQol 5D, Pain Visual Analogue Scale), referral experience, and the importance of surgeon choice, surgeon reputation, and wait time. We used logistic regression to build models for the 2 objectives. RESULTS: We obtained 176 respondents (response rate, 58%), 60% female, 65% knee patients, mean age of 65 years, with no significant differences between responders versus nonresponders. Forty-three percent requested a particular surgeon. Seventy-one percent were referred to a specific surgeon. Patients who rated surgeon choice as very/extremely important [adjusted odds ratio (OR), 6.54; 95% confidence interval (CI), 2.57-16.64] and with household incomes of $90,000+ versus <$30,000 (OR, 5.74; 95% CI, 1.56-21.03) were more likely to request a particular surgeon. Hip patients (OR, 3.03; 95% CI, 1.18-7.78), better Physical Component Summary-12 (OR, 1.29; 95% CI, 1.02-1.63), and patients who rated surgeon choice as very/extremely important (OR, 3.88; 95% CI, 1.56-9.70) were more likely to be referred to a specific surgeon. CONCLUSIONS: Most patients want some choice in the referral decision. Providing sufficient information is important, so that patients are aware of their choices and can make an informed choice. Some patients prefer a particular surgeon despite longer wait times.
Assuntos
Artroplastia de Substituição/psicologia , Preferência do Paciente/psicologia , Encaminhamento e Consulta/estatística & dados numéricos , Idoso , Artroplastia de Substituição/estatística & dados numéricos , Feminino , Humanos , Renda/estatística & dados numéricos , Masculino , Ortopedia/normas , Ortopedia/estatística & dados numéricos , Preferência do Paciente/estatística & dados numéricos , Qualidade de Vida , Inquéritos e Questionários , Listas de EsperaRESUMO
BACKGROUND: While some studies have identified patient readiness as a key component in their decision whether to have total joint replacement surgery (TJR), none have examined how patients determine their readiness for surgery. The study purpose was to explore the concept of patient readiness and describe the factors patients consider when assessing their readiness for TJR. METHODS: Nine focus groups (4 pre-surgery, 5 post-surgery) were held in four Canadian cities. Participants had been either referred to or seen by an orthopaedic surgeon for TJR or had undergone TJR. The method of analysis was qualitative thematic analysis. RESULTS: There were 65 participants, 66% female and 34% male, 80% urban, with an average age of 65 years (SD 10). Readiness reflected both the surgeon's advice that the patient was clinically ready for surgery and the patient's feeling that they were both mentally and physically ready for surgery. Mental readiness was described as an internal state or feeling of being ready or prepared while physical readiness was described as being physically fit and in good shape for surgery. Factors associated with readiness included: 1) pain: its severity, the ability to cope with it, and how it affected their quality of life; 2) mental preparation; 3) physical preparation; 4) the optimal timing of surgery, including age, anticipated rate of deterioration, prosthesis lifespan and the length of the waiting list. CONCLUSIONS: Patient readiness should be assessed prior to TJR. By assessing patient readiness, health professionals can elucidate and deal with concerns and fears, understand and calibrate expectations, assess coping strategies, and use this information to help determine optimal timing, both before and after the surgical consultation.
Assuntos
Artroplastia de Substituição , Atitude Frente a Saúde , Tomada de Decisões , Pacientes/psicologia , Adaptação Psicológica , Idoso , Canadá , Feminino , Grupos Focais , Humanos , Masculino , Medição da Dor , Pesquisa Qualitativa , Qualidade de VidaRESUMO
BACKGROUND: Metal-on-metal hip resurfacing was developed for younger, active patients as an alternative to THA, but it remains controversial. Study heterogeneity, inconsistent outcome definitions, and unstandardized outcome measures challenge our ability to compare arthroplasty outcomes studies. QUESTIONS/PURPOSES: We asked how early revisions or reoperations (within 5 years of surgery) and overall revisions, adverse events, and postoperative component malalignment compare among studies of metal-on-metal hip resurfacing with THA among patients with hip osteoarthritis. Secondarily, we compared the revision frequency identified in the systematic review with revisions reported in four major joint replacement registries. METHODS: We conducted a systematic review of English language studies published after 1996. Adverse events of interest included rates of early failure, time to revision, revision, reoperation, dislocation, infection/sepsis, femoral neck fracture, mortality, and postoperative component alignment. Revision rates were compared with those from four national joint replacement registries. Results were reported as adverse event rates per 1000 person-years stratified by device market status (in use and discontinued). Comparisons between event rates of metal-on-metal hip resurfacing and THA are made using a quasilikelihood generalized linear model. We identified 7421 abstracts, screened and reviewed 384 full-text articles, and included 236. The most common study designs were prospective cohort studies (46.6%; n = 110) and retrospective studies (36%; n = 85). Few randomized controlled trials were included (7.2%; n = 17). RESULTS: The average time to revision was 3.0 years for metal-on-metal hip resurfacing (95% CI, 2.95-3.1) versus 7.8 for THA (95% CI, 7.2-8.3). For all devices, revisions and reoperations were more frequent with metal-on-metal hip resurfacing than THA based on point estimates and CIs: 10.7 (95% CI, 10.1-11.3) versus 7.1 (95% CI, 6.7-7.6; p = 0.068), and 7.9 (95% CI, 5.4-11.3) versus 1.8 (95% CI, 1.3-2.2; p = 0.084) per 1000 person-years, respectively. This difference was consistent with three of four national joint replacement registries, but overall national joint replacement registries revision rates were lower than those reported in the literature. Dislocations were more frequent with THA than metal-on-metal hip resurfacing: 4.4 (95% CI, 4.2-4.6) versus 0.9 (95% CI, 0.6-1.2; p = 0.008) per 1000 person-years, respectively. Adverse event rates change when discontinued devices were included. CONCLUSIONS: Revisions and reoperations are more frequent and occur earlier with metal-on-metal hip resurfacing, except when discontinued devices are removed from the analyses. Results from the literature may be misleading without consistent definitions, standardized outcome metrics, and accounting for device market status. This is important when clinicians are assessing and communicating patient risk and when selecting which device is most appropriate for individual patients.
Assuntos
Artroplastia de Quadril/instrumentação , Articulação do Quadril/cirurgia , Prótese de Quadril , Próteses Articulares Metal-Metal , Osteoartrite do Quadril/cirurgia , Artroplastia de Quadril/efeitos adversos , Fenômenos Biomecânicos , Distribuição de Qui-Quadrado , Articulação do Quadril/fisiopatologia , Humanos , Funções Verossimilhança , Modelos Lineares , Osteoartrite do Quadril/diagnóstico , Osteoartrite do Quadril/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/cirurgia , Desenho de Prótese , Falha de Prótese , Reoperação , Fatores de Risco , Propriedades de Superfície , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Controlling escalating costs of hip (THA) and knee arthroplasty (TKA) without compromising quality of care has created the need for innovative system reorganization to inform sustainable solutions. QUESTIONS/PURPOSES: The purpose of this study was to inform estimates of the value of THA and TKA by determining: (1) the data sources data required to obtain costs across the care continuum; (2) the data required for different analytical perspectives; and (3) the relative costs across the continuum of care. METHODS: Within the context of a pragmatic randomized controlled trial comparing alternative care pathways, we captured healthcare resource use: (1) 12 months before surgery; (2) inpatient; (3) acute recovery; and (4) long-term recovery 3 and 12 months postsurgery. We established a standardized costing model to reflect both the healthcare payer and patient perspectives. RESULTS: Multiple data sources from regional health authorities, administrative databases, and patient questionnaire were required to estimate costs across the care continuum. Inpatient and acute care costs were approximately 60% of the total with the remaining 40% incurred 12 months presurgery and 12 months postsurgery. Regional health authorities bear close to 60%, and patient costs are approximately 30% of the mean total costs, most of which were incurred after the acute inpatient stay. CONCLUSIONS: To fully understand the value of an orthopaedic intervention such as THA and TKA, a broader perspective than one limited to the payer should be considered using a standardized measurement framework over a relevant time horizon and from multiple viewpoints to reflect the substantial patient burden and support sustainable improvement over the care continuum. LEVEL OF EVIDENCE: Level III, economic and decision analyses study. See Guidelines for Authors for a complete description of levels of evidence.
Assuntos
Artroplastia de Quadril/economia , Artroplastia do Joelho/economia , Custos de Cuidados de Saúde , Análise Custo-Benefício , HumanosRESUMO
Despite various health system improvements across Alberta, the wait times benchmark was not being met for all patients requiring hip or knee arthroplasty. Alberta Health Services Bone and Joint Clinical Network working groups, in collaboration with other provincial organizations, gained consensus on the development and implementation of a set of provincial Wait Times Rules. These rules standardize the definition and measurement of data elements specific to joint replacement and distinguish between voluntary (patient-related) versus involuntary (healthcare system-related) wait times. Collectively, this information will help identify trends in wait times and more accurately show where wait times can be reduced.
Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Alocação de Recursos para a Atenção à Saúde/normas , Regionalização da Saúde/normas , Listas de Espera , Alberta , Benchmarking/métodos , Consenso , Coleta de Dados/métodos , Alocação de Recursos para a Atenção à Saúde/estatística & dados numéricos , Humanos , Padrões de Referência , Regionalização da Saúde/estatística & dados numéricosRESUMO
OBJECTIVE: To examine the validity of a newly developed prediction model translating osteoarthritis (OA)-specific health-related quality of life (HRQL) scores measured using the Western Ontario and McMaster Osteoarthritis Index (WOMAC) into generic utility-based HRQL scores measured using the Health Utilities Index Mark 3 (HUI3). METHODS: Preintervention data from 145 patients with hip OA and complete WOMAC and HUI3 baseline assessments from the Alberta Hip Improvement Project study were used to validate three utility prediction models. These models were estimated using data from a previous study of knee OA patients. Predictive performance was assessed using the mean absolute prediction error (MAE) criterion and several other criteria. RESULTS: The validation sample appeared healthier (on the basis of the HUI3 and WOMAC) than the subjects used toestimate the prediction models. Nevertheless, the validation sample outperformed the predictive performance of the model sample. The results from the validation sample support the conclusions from the original study in that the primary model identified during model development (a model using WOMAC subscales, their interactions, their square terms, age, OA duration, their square terms, and gender) performed better on the MAE criterion than competing models. CONCLUSION: These results support the external validity of the prediction model for the retrospective estimation of HUI3 utility scores for use in economic evaluation.
Assuntos
Materiais Biocompatíveis/uso terapêutico , Ácido Hialurônico/análogos & derivados , Osteoartrite do Quadril/tratamento farmacológico , Qualidade de Vida , Índice de Gravidade de Doença , Feminino , Indicadores Básicos de Saúde , Humanos , Ácido Hialurônico/uso terapêutico , Masculino , Medição da Dor , Valor Preditivo dos Testes , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de RegressãoRESUMO
PURPOSE: The aim of the study is to develop a method to estimate osteoarthritis (OA) incidence by using administrative health care databases. METHODS: Using actual counts of OA diagnoses in different periods, we generated an equation that estimated the number of new OA diagnoses based on the length of time used for excluding prevalent OA cases. Physicians billing files from 1983 to 2002 maintained at Alberta Health and Wellness were used to verify the proposed method. Age- and sex-specific and crude OA incidences in 2002 were calculated by using this method. RESULTS: Women aged 50 to 59 years had the greatest incidence. For men, the greatest incidence was in the 60- to 69-year age category. Crude incidences for women and men were 1103 and 934 per 100,000 person-years, respectively. The overall crude rate was 1040 per 100,000 person-years. CONCLUSIONS: Modified power function accurately summarizes the relationship between number of first OA diagnoses and length of the clearance period and thus provides an effective model to estimate OA incidence. Not restricted to OA, this model also can be implemented to estimate incidences of other chronic conditions.
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Bases de Dados Factuais , Seguro de Serviços Médicos/estatística & dados numéricos , Modelos Estatísticos , Programas Nacionais de Saúde/estatística & dados numéricos , Osteoartrite/epidemiologia , Sistema de Registros , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Alberta/epidemiologia , Planos de Pagamento por Serviço Prestado/estatística & dados numéricos , Feminino , Humanos , Incidência , Revisão da Utilização de Seguros , Masculino , Pessoa de Meia-Idade , Probabilidade , Medição de Risco , Distribuição por SexoRESUMO
A robust accountability strategy is at the core of creating a safe, efficient, effective and sustainable system of healthcare. The commitment to be accountable must extend far beyond the providers of care to include every person involved in the funding, administration, delivery and support of patient care (both directly and indirectly). The Alberta Bone and Joint Health Institute has fostered a new system that will measure, analyze and give valuable feedback to all stakeholders in all three essential domains of system accountability: access, quality and cost. The Institute has employed four key strategies to create system accountability in a hip and knee pilot project: collaboration between stakeholders in defining goals and measures that matter to them; the use of "world's best evidence" to drive decisions and to establish goals and benchmarks to measure against; collection of useful data and its analysis to inform improvement decisions; and timely feedback of relevant data in domains of interest to stakeholders on system outputs in the key domains. While these strategies have not yet been proven to be effective in creating the desired "culture of accountability," they are having a significant clinical impact and do have potential to lead to that outcome.
Assuntos
Comportamento Cooperativo , Atenção à Saúde/organização & administração , Acessibilidade aos Serviços de Saúde/organização & administração , Cultura Organizacional , Indicadores de Qualidade em Assistência à Saúde/organização & administração , Alberta , Artroplastia de Quadril , Artroplastia do Joelho , Atenção à Saúde/economia , Custos de Cuidados de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde/organização & administração , Acessibilidade aos Serviços de Saúde/economia , Humanos , Programas Nacionais de Saúde/organização & administração , Mudança Social , Listas de EsperaRESUMO
We established botulinum type-A toxin (BTX-A) injections as a powerful tool to cause knee extensor weakness in New Zealand White (NZW) rabbits. The purpose of this study was to determine if BTX-A induced quadriceps weakness causes muscle dysfunction beyond that caused by anterior cruciate ligament (ACL) transection in the knee of NZW rabbits. Twenty animals were randomly divided into four study groups (n=5 each); uninjected controls, BTX-A injection alone, ACL transection alone, BTX-A injection and ACL transection combined. Isometric knee extensor torque, quadriceps muscle mass, and vertical and anterior-posterior ground reaction forces were measured four weeks post single (BTX-A and ACL), unilateral intervention. Muscle weakness, muscle atrophy and decrease in ground reaction forces were all significantly greater for the experimental compared to the untreated contralateral legs. BTX-A injection produced a greater deficit in quadriceps mass and knee extensor torque than ACL transection alone, but produced smaller deficits in the ground reaction forces. ACL transection superimposed on BTX-A injection did not change either knee extensor torque production or muscle mass. Together these results suggest that BTX-A injection causes great force and muscle mass deficits, and affects functional gait in a significant manner, but it has no measurable functional effect when superimposed on ACL transection, at least not in the acute protocol tested here. Hopefully, BTX-A injection for acutely enhancing the degree of muscle weakness in otherwise untreated animals, or in experimental models of osteoarthritis, will help in investigating the role of muscle weakness in joint degeneration.
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Lesões do Ligamento Cruzado Anterior , Toxinas Botulínicas/toxicidade , Instabilidade Articular/fisiopatologia , Traumatismos do Joelho/fisiopatologia , Debilidade Muscular/induzido quimicamente , Animais , Marcha , Debilidade Muscular/fisiopatologia , Atrofia Muscular/etiologia , Coelhos , TorqueRESUMO
Osteoarthritic patients show only a weak association between radiographic signs of joint disease and joint pain and disability. Conversely, muscle weakness is one of the earliest and most common symptoms of patients with osteoarthritis (OA). However, while many experimental models of osteoarthritis include a component of muscular weakness, no model has isolated this factor satisfactorily. Therefore, the purpose of this study was to develop and validate an experimental animal model of muscle weakness for future use in the study of OA. Botulinum Type-A toxin (BTX-A) was uni-laterally injected into the quadriceps musculature of New Zealand white rabbits (3.5 units/kg). Isometric knee extensor torque at a range of knee angles and stimulation frequencies, and quadriceps muscle mass, were quantified for control animals, and at one- and six-months post-repeated injections, in both, the experimental and the contralateral hindlimb. Ground reaction forces were measured in all animals while hopping across two force platforms. Isometric knee extension torque and quadriceps muscle mass was systematically decreased in the experimental hindlimb. Vertical ground reaction forces in the push off phase of hopping were also decreased in the experimental compared to control hindlimbs. We conclude that BTX-A injection into the rabbit musculature creates functional and absolute muscle weakness in a reproducible manner. Therefore, this model may be used to systematically study the possible effects of muscle weakness on joint degeneration, either as an isolated intervention, or in combination with other interventions (anterior cruciate ligament transection, meniscectomy) known to create knee joint degeneration.
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Toxinas Botulínicas/toxicidade , Debilidade Muscular/induzido quimicamente , Osteoartrite/etiologia , Animais , Modelos Animais de Doenças , Articulação do Joelho/patologia , Debilidade Muscular/patologia , Debilidade Muscular/fisiopatologia , Músculo Esquelético/patologia , Coelhos , TorqueRESUMO
Improving quality of care and maximizing efficiency are priorities in hip and knee replacement, where surgical demand and costs increase as the population ages. The authors describe the integrated structure and processes from the Continuous Quality Improvement (CQI) Program for Hip and Knee Replacement Surgical Care and summarize lessons learned from implementation. The Triple Aim framework and 6 dimensions of quality care are overarching constructs of the CQI program. A validated, evidence-based clinical pathway that measures quality across the continuum of care was adopted. Working collaboratively, multidisciplinary experts embedded the CQI program into everyday practices in clinics across Alberta. Currently, 83% of surgeons participate in the CQI program, representing 95% of the total volume of hip and knee surgeries. Biannual reports provide feedback to improve care processes, infrastructure planning, and patient outcomes. CQI programs evaluating health care services inform choices to optimize care and improve efficiencies through continuous knowledge translation.
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Artroplastia de Quadril/métodos , Artroplastia do Joelho/métodos , Melhoria de Qualidade , Gestão da Qualidade Total , Alberta , Procedimentos Clínicos , Medicina Baseada em Evidências/métodos , Humanos , Equipe de Assistência ao Paciente/estatística & dados numéricos , Cirurgiões/estatística & dados numéricosRESUMO
INTRODUCTION: The routine use of magnetic resonance imaging (MRI) for the assessment of acute knee injuries is controversial. The goal of this study is to present an audit of patients seen in a dedicated Acute Knee Injury Clinic (AKIC) to determine the frequency and appropriateness of MRI utilization. METHODS: A retrospective review identified all patients who had an MRI and a randomly selected control group without MRI. The MRI was classified based on whether it was ordered by the AKIC team or by an external clinician. The consensus-based 'Indications for Urgent MRI in Acute Soft Tissue Knee Problems' were applied to both groups. An MRI was considered appropriate if any of the indications were met. RESULTS: The overall MRI utilization rate was 23% (142/611). Of the MRIs performed, 32% (46/142) met the indications. About 94% (33/35) of the MRIs ordered by the AKIC experts met the indications, compared to only 12% (13/107) of those ordered externally. No patients in the control group met the indications. Diagnoses were similar between groups. DISCUSSION: These results suggest that application of guidelines by experts in knee evaluation can significantly reduce expensive MRI utilization in patients with acute knee injuries without negatively impacting the appropriate diagnosis and disposition.
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Fidelidade a Diretrizes , Traumatismos do Joelho/diagnóstico , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/estatística & dados numéricos , Encaminhamento e Consulta , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Traumatismos do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
OBJECTIVE: With aging and obesity trends, the incidence and prevalence of osteoarthritis (OA) is expected to rise in Canada, increasing the demand for health resources. Resource planning to meet this increasing need requires estimates of the anticipated number of OA patients. Using administrative data from Alberta, we estimated OA incidence and prevalence rates and examined their sensitivity to alternative case definitions. METHODS: We identified cases in a linked data set spanning 1993 to 2010 (population registry, Discharge Abstract Database, physician claims, Ambulatory Care Classification System, and prescription drug data) using diagnostic codes and drug identification numbers. In the base case, incident cases were captured for patients with an OA diagnostic code for at least 2 physician visits within 2 years or any hospital admission. Seven alternative case definitions were applied and compared. RESULTS: Age- and sex-standardized incidence and prevalence rates were estimated to be 8.6 and 80.3 cases per 1,000 population, respectively, in the base case. Physician claims data alone captured 88% of OA cases. Prevalence rate estimates required 15 years of longitudinal data to plateau. Compared to the base case, estimates are sensitive to alternative case definitions. CONCLUSION: Administrative databases are a key source for estimating the burden and epidemiologic trends of chronic diseases such as OA in Canada. Despite their limitations, these data provide valuable information for estimating disease burden and planning health services. Estimates of OA are mostly defined through physician claims data and require a long period of longitudinal data.
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Custos de Cuidados de Saúde , Recursos em Saúde/economia , Osteoartrite/economia , Osteoartrite/epidemiologia , Planejamento de Assistência ao Paciente/economia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Alberta , Canadá , Estudos de Coortes , Intervalos de Confiança , Bases de Dados Factuais , Feminino , Previsões , Avaliação Geriátrica/métodos , Recursos em Saúde/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico , Osteoartrite/terapia , Planejamento de Assistência ao Paciente/tendências , Fatores SexuaisRESUMO
Experimental observations suggest that during a ligament tensile strain test, water and glycosaminoglycans are exuded. Many attempts have been tried to model this behaviour using continuum mechanics. We have investigated this unique behaviour and have established three mechanisms which may contribute to the experimental observations: the slackness of the fibres before stretching can lead to a decrease in volume upon straightening; a Poisson's ratio higher than 0.5 from the axial to the lateral direction (as recorded in the literature [Hewitt, J., Guilak, F., Glisson, R. and Parker Vail, T. (2001) "Regional material properties of the human hip joint capsule ligaments", Journal of Orthopaedic Research 19(3), 359-364]) due to the very high level of anisotropy of the tissue; and an osmotic pressure, with a certain level of anisotropy, that causes the swelling of the tissue before loading [Thornton, G.M., Shrive, N.G. and Frank, C.B. (2001) "Altering ligament water content affects ligament pre-stress and creep behaviour", Journal of Orthopaedic Research 19(5), 845-851]. There may be other mechanisms that also contribute in the observed fluid exudation on tensile loading.
Assuntos
Ligamentos/fisiologia , Anisotropia , Humanos , Distribuição de PoissonRESUMO
RATIONALE, AIMS AND OBJECTIVES: Persistently long waiting times for hip and knee total joint arthroplasty (TJA) specialist consultations have been identified as a problem. This study described referral processes and practices, and their impact on the waiting time from referral to consultation for TJA. METHODS: A mixed-methods retrospective study incorporating semi-structured interviews, patient chart reviews and observational studies was conducted at three clinic sites in Alberta, Canada. A total of 218 charts were selected for analysis. Standardized definitions were applied to key event dates. Performance measures included waiting times percentage of referrals initially accepted. Voluntary (patient-related) and involuntary (health system-related) waiting times were quantified. RESULTS: All three clinics had defined, but differing, referral processing rules. The mean time from referral to consultation ranged from 51 to 139 business days. Choosing a specific surgeon for consultation rather than a next available surgeon lengthened waits by 10-47 business days. Involuntary waiting times accounted for at least 11% of total waiting time. Approximately 40-80% of the time patients with TJA wait for surgery was in the consultation period. Fifty-four per cent of new referrals were initially rejected, prolonging patient waits by 8-46 business days. CONCLUSIONS: Our results suggest that variation in referral processing led to increased waiting times for patients. The large proportion of total wait attributable to waiting for a surgical consultation makes failure to measure and evaluate this period a significant omission. Improving referral processes and decreasing variation between clinics would improve patient access to these specialist referrals in Alberta.
Assuntos
Artroplastia de Quadril/estatística & dados numéricos , Artroplastia do Joelho/estatística & dados numéricos , Ortopedia , Médicos de Atenção Primária , Encaminhamento e Consulta/organização & administração , Alberta , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/organização & administração , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Humanos , Encaminhamento e Consulta/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Tempo , Listas de EsperaRESUMO
PURPOSE: The effects of nonselective and selective cyclooxygenase-2 specific (COX-2) nonsteroidal anti-inflammatory drug (NSAID) use on the progression of chronic kidney disease (CKD) is uncertain. Due to the high prevalence of both CKD and NSAID use in older adults, we sought to determine the association between NSAID use and the progression of CKD in an elderly community-based cohort. METHODS: All subjects > or =66 years of age who had at least one serum creatinine measurement in 2 time periods (July-December, 2001 and July-December, 2003) were included. Multiple logistic regression analyses, including covariates for age, sex, baseline estimated glomerular filtration rate (eGFR), diabetes, and comorbidity were used to explore the associations of NSAID use on the primary (decrease in eGFR of > or =15 mL/min/1.73) and secondary (mean change in eGFR) outcomes. RESULTS: A total of 10,184 subjects (mean age 76 years; 57% female) were followed for a median of 2.75 years. High-dose NSAID users (upper decile of cumulative NSAID exposure) experienced a 26% increased risk for the primary outcome (odds ratio [OR] 1.26, 95% confidence interval [CI], 1.04-1.53). A linear association between cumulative NSAID dose and change in mean GFR also was seen. No risk differential was identified between selective and nonselective NSAID users. CONCLUSIONS: High cumulative NSAID exposure is associated with an increased risk for rapid CKD progression in the setting of a community-based elderly population. For older adult patients with CKD, these results suggest that nonselective NSAIDs and selective COX-2 inhibitors should be used cautiously and chronic exposure to any NSAID should be avoided.