Our review of data from national registries supports the continued use of bipolar hemiarthroplasty in femoral-neck fracture in the elderly and identifies age, method of fixation and surgical approach as important prognostic variables in determining implant survival.

The current literature on femoroacetabular impingement (FAI) is focused on acetabular orientation and femoral head asphericity, with little emphasis on the effect of version of the femoral neck. A biomechanical model was developed to determine the causative effect, if any, of femoral retroversion on hip contact stress and, if present, delineate the type of FAI with femoral neck retroversion. Five pairs of cadaveric hips (n = 10) were tested by loading the hip in 90° of flexion and measured the peak joint pressure and the location of the peak joint pressure. The experiment was repeated after performing a subtrochanteric osteotomy and retroverting the proximal femur by 10°. Ten hips were successfully tested, with one hip excluded due to an outlier value for peak joint pressure. Retroversion of the proximal femur significantly increased the magnitude of mean peak joint pressure. With retroversion, the location of the peak joint pressure was shifted posteroinferiorly in all cases. In conclusion, femoral neck retroversion increases peak joint pressure in the flexed position and may act as a cause of femoroacetabular impingement. The location of peak joint pressure suggests a pincer-type impingement with retroversion. The version of femoral neck should be assessed as a possible causative factor in patients with FAI, especially those with pincer-type impingement.

Hypertension remains a significant risk factor for development of congestive heart failure CHF), with various mechanisms contributing to both systolic and diastolic dysfunction. The pathogenesis of myocardial changes includes structural remodeling, left ventricular hypertrophy, and fibrosis. Activation of the sympathetic nervous system and renin-angiotensin system is a key contributing factor of hypertension, and thus interventions that antagonize these systems promote regression of hypertrophy and heart failure. Control of blood pressure is of paramount importance in improving the prognosis of patients with heart failure.

Attainment of a neutral mechanical axis is one of the primary goals in total knee arthroplasty (TKA). The accuracy of the procedure is evaluated by measuring the hip-knee-ankle angle (HKAA) on long leg radiographs. Rotation of the lower limb and knee flexion could possibly affect the HKAA measured on plain radiographs. In this study, a TKA was performed on a saw-bone model of the lower limb. Long leg radiographs from the femoral head to the ankle were obtained after sequentially varying the alignment of the knee model in 5-degree increments of flexion and rotation, from 0 to 20 degrees. Flexion or external rotation alone, up to 20 degrees changed the HKAA by no more than 1 degree. A combination of flexion and external rotation progressively altered the HKAA. The HKAA was altered by 5 degrees at a combination of 15- or 20-degree flexion and 20-degree external rotation. While flexion or external rotation alone had little effect on the HKAA, a combination of the two altered it substantially.

No abstract

No abstract

Background Sleep quality and quantity are severely reduced in critically ill patients receiving mechanical ventilation with potential for adverse consequences. Our objective was to synthesize the randomized controlled trials (RCTs) that measured the efficacy of sleep-promoting interventions on sleep quality and quantity in critically ill patients. Methods We included RCTs that objectively measured sleep with electroencephalography or its derivatives and excluded observational studies and those that measured sleep by subjective reports. The research was performed according to PRISMA guidelines. Results Of 6,022 studies identified, 13 studies met eligibility criteria involving 296 critically-ill patients. Eight trials looked at different modes of mechanical ventilation as sleep interventions, and the remaining five involved pharmacological, non-pharmacological, or environmental interventions. Meta-analysis of the studies revealed that sleep-promoting interventions improved sleep quantity (pooled standardized mean of differences [SMD] 0.37, 95%CI: 0.05, 0.69; P=0.02) and sleep quality through reduction in sleep fragmentation (SMD −0.31; 95%CI −0.60, −0.01; P=0.04). Subgroup analysis revealed that timed-modes of ventilation improved sleep quantity when compared to spontaneous-modes of ventilation (SMD 0.45, 95%CI 0.10, 0.81; P=0.01). Non-mechanical ventilation interventions tended to improve sleep quantity (SMD 0.65; 95%CI; −0.03, 1.33; P=0.06) and tended to reduce sleep fragmentation (SMD −0.29; 95% CI −0.61, 0.03; P=0.07). Conclusions The synthesized evidence suggests that both mechanical ventilation and non-mechanical ventilation-based therapies improve sleep quantity and quality in critically ill patients but the clinical significance is unclear. In the future, adequately-powered multi-center RCTs involving pharmacological interventions to promote sleep in critically ill patients are warranted.

No abstract