79 research outputs found
The influence of graft choice on isokinetic muscle strength 4-24 months after anterior cruciate ligament reconstruction
Regaining adequate strength of the quadriceps and hamstrings after anterior cruciate ligament (ACL) reconstruction is important for maximizing functional performance. However, the outcome of muscle strength after either BPTB or hamstrings autograft is unclear given the plethora of published studies that report post-operative muscle strength. The purpose of this study was to systematically compare the muscle strength of patients who have undergone ACL reconstruction using either Bone Patellar Tendon Bone (BPTB) or Hamstrings (HST) autograft. The databases of MEDLINE, Cinahal and EMBASE were systematically searched for articles that report muscle strength outcome following ACL reconstruction. The quality of the studies was evaluated and a meta-analysis of the muscle strength outcomes was conducted on reported data. Fourteen studies were included in this systematic review: eight Randomized Control Studies (RCT) and six non-Randomized Control Studies (non-RCT). A meta-analysis was performed involving eight of the included studies (4 RCTs andamp; 3 non-RCTs). At 60A degrees/s and 180A degrees/s, patients with BPTB graft showed a greater deficit in extensor muscle strength and lower deficit in flexor muscle strength compared with patients with HST. This systematic review of Level III evidence showed that isokinetic muscle strength deficits following ACL reconstruction are associated with the location of the donor site. These deficits appear to be unresolved up to 2 years after ACL reconstruction. III.The original publication is available at www.springerlink.com:Sofia A Xergia, Jodie A McClelland, Joanna Kvist, Haris S Vasiliadis and Anastasios D Georgoulis, The influence of graft choice on isokinetic muscle strength 4-24 months after anterior cruciate ligament reconstruction, 2011, KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY, (19), 5, 768-780.http://dx.doi.org/10.1007/s00167-010-1357-0Copyright: Springer Science Business Mediahttp://www.springerlink.com
VELOCITY AT LACTATE THRESHOLD AND RUNNING ECONOMY MUST ALSO BE CONSIDERED ALONG WITH MAXIMAL OXYGEN UPTAKE WHEN TESTING ELITE SOCCER PLAYERS DURING PRESEASON
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Three-dimensional tibiofemoral kinematics of the anterior cruciate ligament-deficient and reconstructed knee during walking
Background: It is possible that gait abnormalities may play a role in the pathogenesis of meniscal or chondral injury as well as osteoarthritis of the knee in patients with anterior cruciate ligament deficiency. Hypothesis: The three-dimensional kinematics of anterior cruciate ligament-deficient knees are changed even during low-stress activities, such as walking, but can be restored by reconstruction. Study Design: Case control study. Methods: Using a three-dimensional optoelectronic gait analysis system, we examined 13 patients with anterior cruciate ligament-deficient knees, 21 patients with anterior cruciate ligament-reconstructed knees, and 10 control subjects with uninjured knees during walking. Results: Normal patterns of knee flexion-extension, abduction-adduction, and internal-external rotation during the gait cycle were maintained by all subjects. A significant difference in tibial rotation angle during the initial swing phase was found in anterior cruciate ligament-deficient knees compared with reconstructed and control knees. The patients with anterior cruciate ligament-deficient knees rotated the tibia internally during the initial swing phase, whereas the others rotated externally. Conclusions: Patients with anterior cruciate ligament-deficient knees experienced repeated episodes of rotational instability during walking, whereas patients with reconstruction experienced tibial rotation that is closer to normal. Clinical Relevance: Repeated episodes of knee rotational instability may play a role in the development of pathologic kne
New insights into anterior cruciate ligament deficiency and reconstruction through the assessment of knee kinematic variability in terms of nonlinear dynamics
National audienc
Associations between serum vitamin D status and the cardiometabolic profile of patients with obstructive sleep apnea
Purpose: Obstructive sleep apnea (OSA) and the metabolic syndrome (MetS) frequently coexist. Low serum vitamin D has been positively associated with OSA presence and severity; however, data on its link to cardiometabolic features in patients with OSA remain scarce. We aimed to assess serum 25-hydroxyvitamin D [25(OH)D] and explore its association with cardiometabolic parameters in OSA. Methods: This was a cross-sectional study among 262 patients (49 ± 9 years old, 73% men) with polysomnography-diagnosed OSA. Participants were evaluated in terms of anthropometric indices, lifestyle habits, blood pressure, biochemical, plasma inflammatory and urinary oxidative stress markers, and the presence of MetS. Serum 25(OH)D was assessed by chemiluminescence, and vitamin D deficiency (VDD) was defined as 25(OH)D < 20 ng/mL. Results: Median (1st, 3rd quartile) serum 25(OH)D levels were 17.7 (13.4, 22.9) ng/mL and 63% of participants had VDD. Serum 25(OH)D correlated negatively with body mass index (BMI), homeostasis model of assessment of insulin resistance (HOMA-IR), total cholesterol, low-density lipoprotein cholesterol, triglycerides, high-sensitivity C-reactive protein (hsCRP), and urinary oxidized guanine species (oxG), and positively with high-density lipoprotein cholesterol (all P < 0.050). In logistic regression analysis, serum 25(OH)D was associated with lower odds of MetS [odds ratio (95% confidence interval): 0.94 (0.90–0.98)], after adjustment for age, sex, season of blood sampling, Mediterranean diet score, physical activity, smoking, apnea–hypopnea index, HOMA-IR, hsCRP, and oxG. In the same multivariate model, VDD was associated with ~ twofold greater odds of MetS [2.39 (1.15, 4.97)]. Conclusion: VDD is highly prevalent and is associated with a detrimental cardiometabolic profile among patients with OSA. © 2023, The Author(s)
Krylov-Subspace Preconditioners for Discontinuous Galerkin Finite Element Methods
Standard (conforming) finite element approximations of convection-dominated convection-diffusion problems often exhibit poor stability properties that manifest themselves as non-physical oscillations polluting the numerical solution. Various techniques have been proposed for the stabilisation of finite element methods (FEMs) for convection-diffusion problems, such as the popular streamline upwind Petrov-Galerkin (SUPG) method, and its variants. During the last decade, families of discontinuous Galerkin finite element methods (DGFEMs) have been proposed for the numerical solution of convection-diffusion problems, due to the many attractive properties they exhibit. In particular, DGFEMs admit good stability properties, they offer flexibility in the mesh design (irregular meshes are admissible) and in the imposition of boundary conditions (Dirichlet boundary conditions are weakly imposed), and they are increasingly popular in the context of hp-adaptive algorithms. The increase in popularity for DGFEMs has created a corresponding demand for developing corresponding linear solvers. This work aims to provide an overview of the current state of affairs in the solution of DGFEM-linear problems and present some recent results on the preconditioning of stiffness matrices arising from DGFEM discretisations of steady-state convection-diffusion boundary-value problems. More specifically, preconditioners are derived for which theoretical results indicate GMRES performance independent of discretisation parameters
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