Bilateral Alterations in Running Mechanics and Quadriceps Function Following Unilateral Anterior Cruciate Ligament Reconstruction

Background Following anterior cruciate ligament reconstruction (ACLR), individuals have quadriceps muscle impairments that influence gait mechanics and may contribute to an elevated risk of knee osteoarthritis. Objectives To compare running mechanics and quadriceps function between individuals who have undergone ACLR and those in a control group, and to evaluate the association between quadriceps function and running mechanics. Methods In this controlled, cross-sectional laboratory study, 38 individuals who previously underwent primary unilateral ACLR (mean ± SD time since reconstruction, 48.0 ± 25.0 months) were matched to 38 control participants based on age, sex, and body mass index, and underwent assessments of quadriceps muscle performance and running biomechanics. Quadriceps muscle performance was assessed via isokinetic and isometric knee extension peak torque and rate of torque development (RTD) over 2 time frames: 0 to 100 milliseconds (RTD100) and 0 to 200 milliseconds (RTD200). Running evaluation included assessment of the knee flexion angle (KFA), knee extension moment (KEM), rate of knee extension moment (RKEM), vertical instantaneous loading rate, and vertical impact peak. Results On average, there was a smaller KFA (P = .016) in the involved limb compared to the uninvolved limb in the ACLR group. Compared to limbs in the control group, involved limbs in the ACLR group had lower RTD100 (P = .015), lower peak torque at 60°/s (P = .007), lower peak torque at 180°/s (P = .016), smaller KFA (P\u3c.001), lower KEM (P = .001), lower RKEM (P = .004), and higher vertical instantaneous loading rate (P = .016). Compared to limbs in the control group, uninvolved limbs in the ACLR group had lower RTD100 (P = .003), lower peak torque at 60°/s (P = .017), and smaller KFA (P = .01). For the involved limbs in the ACLR group, there was a low correlation between isokinetic peak torque at 180°/s and RKEM (r = 0.38, P = .01), and a negligible correlation between RTD100 and RKEM (r = 0.26, P\u3c.05). No differences were found in isometric strength for any comparison. Conclusion Individuals who have undergone ACLR have bilateral alterations in running mechanics that are weakly associated with diminished quadriceps muscle performance

A frequência da utilização de profilaxia para trombose venosa profunda em pacientes clínicos hospitalizados The frequency of using prophylaxis to deep venous thrombosis among clinical hospitalized patients

CONTEXTO: A profilaxia para trombose venosa profunda (TVP) está sendo subutilizada, ainda que seja a causa mais comum de mortalidade hospitalar passível de prevenção. Assim, é relevante responder à pergunta de pesquisa: qual a frequência da utilização de profilaxia para TVP em pacientes clínicos hospitalizados? OBJETIVO: Determinar a frequência da utilização de profilaxia para TVP em pacientes clínicos hospitalizados. A hipótese foi de 20%. MÉTODOS: Tipo de estudo: Estudo transversal de frequência. Local: Hospital Geral do Estado Dr. Osvaldo Brandão Vilela, Maceió, Alagoas. Amostra: Foram incluídos os pacientes clínicos e excluídos os menores de 18 anos, as gestantes e os pacientes hospitalizados há menos de 72 horas. Variável primária: a frequência da utilização de profilaxia para TVP. Variáveis secundárias: a frequência da utilização de métodos físicos e farmacológicos para a prevenção de TVP. Métodos estatísticos: O tamanho da amostra foi de 246 indivíduos (proporção=20%, precisão absoluta=5%, nível de significância=5%). Foram utilizados o teste do qui-quadrado e o intervalo de confiança de 95%. RESULTADOS: A frequência da utilização de profilaxia para TVP foi 33% (80/246; IC95% 2 a 38). A frequência da utilização de métodos físicos para a prevenção de TVP foi 17% (41/246; IC95% 12 a 21) e de métodos farmacológicos foi 26% (64/246; IC95% 21 a 31). CONCLUSÃO: A frequência da utilização de profilaxia para TVP em pacientes clínicos hospitalizados foi 33%.<br>CONTEXT: The prophylaxis to deep venous thrombosis is being underused, although this disease be the most common cause of intrahospital mortality that could be prevented. Thus, it is relevant to answer the research question: what is the frequency of use of prophylaxis to deep venous thrombosis among clinical hospitalized patients? OBJECTIVE: To determine the frequency of use of prophylaxis to deep venous thrombosis in clinical hospitalized patients. The research hypothesis was 20%. METHODS: Cross-sectional study. Setting: Hospital Geral do Estado Dr. Osvaldo Brandão Vilela, Maceió, Alagoas, Brazil. Sample: Clinical hospitalized patients were included. Patients under 18 years-old, pregnant women and those admitted with less than 72 hours of hospitalization were excluded. Primary variable: the frequency of use of prophylaxis to deep venous thrombosis. Secondary variable: the frequency of physical and pharmacological methods to prevent deep venous thrombosis. Statistical Methods: The sample size was 246 individuals (proportion=20%, absolute precision=5%, significance level=5%). The statistical analysis was performed using qui-square test and 95% confidence interval. RESULTS: The frequency of using prophylaxis to deep venous thrombosis was 33% (80/246; CI95% 27 to 38). The frequency of using physical methods to prevent deep venous thrombosis was 17% (41/246; CI95% 12 to 21) and the frequency of using pharmacological methods was 26% (64/246;CI95% 21 to 31). CONCLUSION: The frequency of use of prophylaxis to deep venous thrombosis among clinical hospitalized patients was 33%

Formulation of a Method to Assess Capacity Enhancing Technologies

The demand for air travel is expanding beyond the capacity of existing airports and air traffic control. This excess traffic often results in delays and compromised safety. Therefore, a number of initiatives to improve airport capacity and throughput have been proposed. However, in order to assess the impact of these technologies on commercial air traffic one must move beyond the vehicle to a system-ofsystems point of view. This top-level perspective must include consideration of the aircraft, airports, air traffic management and airlines that make up the airspace system. In addition to the analysis of each of these components and their interactions, a thorough investigation of capacity and throughput technologies requires due consideration of other pressures such as economics, safety and government regulations. Furthermore, the air traffic system is inherently variable with constant changes in everything from fuel prices to the weather. Thus, the development of a modeling environment to be used in the evaluation of technological impacts while encompassing all these sources of uncertainty is the subject of this paper