Adaptive bone-remodeling theory applied to prosthetic-design analysis

The subject of this article is the development and application of computer-simulation methods to predict stress-related adaptive bone remodeling, in accordance with ‘Wolff's Law’. These models are based on the Finite Element Method (FEM) in combination with numerical formulations of adaptive bone-remodeling theories.\ud \ud In the adaptive remodeling models presented, the Strain Energy Density (SED) is used as a feed-back control variable to determine shape or bone density adaptations to alternative functional requirements, whereby homeostatic SED distribution is assumed as the remodeling objective.\ud \ud These models are applied to investigate the relation between ‘stress shielding’ and bone resorption in the femoral cortex around intramedullary prostheses, such as used in Total Hip Arthroplasty (THA). It is shown that the amount of bone resorption depends mainly on the rigidity and the bonding characteristics of the implant. Homeostatic SED can be obtained when the resorption process occurs at the periosteal surface, rather than inside the cortex, provided that the stem is adequately flexible

The incidence of metabolic syndrome and its reversal in a cohort of schizophrenic patients followed for one year

Cross-sectional studies showed a high prevalence of metabolic syndrome in patients with schizophrenia. This study aimed to identify the incidence of metabolic syndrome and its reversal in a non-preselected cohort of chronic psychotic patients in routine practice in one year follow-up and to find variables to describe development and reversal of metabolic syndrome. This cohort study was conducted as part of a disease management program and patients were included if they had two complete assessments in a one year follow-up. We conducted two logistic regressions to find variables to describe the development of metabolic syndrome and the reversal of metabolic syndrome. At the time of the first assessment 35% (n = 92) of the 260 included patients had metabolic syndrome. Within one year 21 patients developed metabolic syndrome and 30 patients had it reversed. This was an incidence of 13% (21/168) and a reversal of 33% (30/92). Smoking, family history of cardiovascular diseases, and duration of disease >6 years was associated with a higher risk of developing metabolic syndrome as well as abdominal obesity and dyslipidemia. Patients with abdominal obesity had a smaller chance of reversing metabolic syndrome. Other variables included in the logistic regression such as receiving cardiovascular/antidiabetic drug treatment or duration of disease >6 years did not alter the risk of reversing the metabolic syndrome. Our study showed that the natural course of metabolic syndrome is dynamic. A considerable number of patients developed or reversed the metabolic syndrome in one year follow-up. (C) 2009 Elsevier Ltd. All rights reserved

Impaction grafting and cemented acetabular revision

No abstract

Histological evaluation of allograft incorporation after cemented and non-cemented hip arthroplasty in the goat

No abstract

A 12-month follow-up study of treating overweight schizophrenic patients with aripiprazole

Objective: To investigate the feasibility of switching overweight schizophrenic patients to aripiprazole and to assess the impact of 12 months of aripiprazole treatment on weight in routine practice. Method: This was a non-controlled cohort study in overweight schizophrenic patients. Data were collected before treatment with aripiprazole was started and at 12-month follow-up. Results: A total of 53 patients were included; of these 55% continued using aripiprazole for 12 months. Aripiprazole treatment for 12 months (P = 0.027) and stopping clozapine or olanzapine treatment (P = 0.038) predicted weight loss (>= 3 kg). Patients receiving aripiprazole monotherapy (n = 16, mean -3.0 kg) had similar weight loss than patients receiving aripiprazole in addition to another antipsychotic drug (n = 13, mean -4.4 kg). Conclusion: In routine practice once aripiprazole treatment was started, more than half of the patients remained on aripiprazole and most of them lost weight. Adding aripiprazole to clozapine gave similar weight loss as monotherapy with aripiprazole

The course of depressive symptoms and prescribing patterns of antidepressants in schizophrenia in a one-year follow-up study

AbstractBackgroundAntidepressants are frequently prescribed in patients with psychotic disorders, but little is known about their effects in routine clinical practice. The objective was to investigate the prescribing patterns of antidepressants in relation to the course of depressive symptoms in patients with psychotic disorders.MethodsA cohort of 214 Dutch patients with psychotic disorders received two assessments of somatic and psychiatric health, including a clinician-rated screening for depressive symptoms, as part of annual routine outcome monitoring.ResultsDepressive symptoms were prevalent among 43% (93) of the patients. Antidepressants were prescribed for 40% (86) of the patients and the majority 83% (71) continued this therapy after one year. Multivariable analysis showed that patients with more severe psychopathology had a higher risk to develop depressive symptoms the following year (OR [95% CI]=0.953 [0.912–0.995]). For patients with depressive symptoms at baseline, polypharmacy was a potential risk factor to keep having depressive symptoms (OR [95% CI]=1.593 [1.123–2.261]). Antidepressant use was not an independent predictor in both analyses.ConclusionsRoutine outcome monitoring in patients with psychotic disorders revealed a high prevalence of depressive symptoms. Antidepressants were frequently prescribed and continued in routine clinical practice