Total hip arthroplasty: leg length inequality impairs functional outcomes and patient satisfaction

Background Leg length inequality (LLI) was identified as a problem of total hip arthroplasty soon after its introduction. Leg lengthening is the most common form of LLI. Possible consequences are limping, neuronal dysfunction and aseptic component loosening. LLI can result in an increased strain both on the contralateral hip joint and on the abductor muscles. We assessed the influence of leg lengthening and shortening on walking capacity, hip pain, limping and patient satisfaction at 2-year follow-up. Methods 478 cases with postoperative lengthening and 275 with shortening were identified, and matched with three controls each. Rigorous adjustment for potential differences in baseline patient characteristics was performed by propensity-score matching of covariates. The arbitrarily defined desired outcomes were a walking capacity >60 minutes, no hip pain, no limping, and excellent patient satisfaction. Differences in not achieving the desired outcomes between the groups were expressed as odds ratios. Results In the lengthened case group, the odds ratio for not being able to walk for an hour was 1.70 (95% CI 1.28-2.26) for cases compared to controls, and the odds ratio for having hip pain at follow-up was 1.13 (95% CI 0.78-1.64). The odds ratio for limping was 2.08 (95% CI 1.55-2.80). The odds ratio for not achieving excellent patient satisfaction was 1.67 (95% CI 1.23-2.28). In the shortening case group, the odds ratio for not being able to walk for an hour was 1.23 (95% CI 0.84-1.81), and the odds ratio for having hip pain at follow-up was 1.60 (95% CI 1.05-2.44). The odds ratio for limping for cases was 2.61 (95% CI 1.78-3.21). The odds ratio for not achieving excellent patient satisfaction was 2.15 (95% CI 1.44-3.21). Conclusions Walking capacity, limping and patient satisfaction were all significantly associated with leg lengthening, whereas pain alleviation was not. In contrast, hip pain, limping and patient satisfaction were all significantly associated with leg shortening, whereas walking capacity was not.

Telomere length increase after weight loss induced by bariatric surgery: results from a 10 years prospective study

BACKGROUND/OBJECTIVES Obesity contributes to telomere attrition. Studies focusing on short-term effects of weight loss have been unable to identify protection of telomere length. This study investigates long-term effects of pronounced weight loss induced by bariatric surgery on telomere length. SUBJECTS/METHODS One hundred forty-two patients were recruited in a prospective, controlled intervention study, follow-up investigations were done after 10.46±1.48 years. A control group of normal weight participants was recruited and followed from 1995 to 2005 in the Bruneck Study. A total of 110 participants from each study was matched by age and sex to compare changes in telomere length. Quantitative PCR was used to determine telomere length. RESULTS Telomere length increased significantly by 0.024±0.14 (P=0.047) in 142 bariatric patients within 10 years after surgery. The increase was different from telomere attrition in an age- and sex-matched cohort population of the Bruneck Study (-0.057±0.18; β=0.08; P=0.003). Significant changes in telomere length disappeared after adjusting for baseline body mass index (BMI) because of general differences in BMI and telomere length between the two study populations (β=0.07; P=0.06). Age was proportional to telomere length in matched bariatric patients (r=0.188; P=0.049) but inversely correlated with telomere length in participants of the Bruneck Study (r=-0.197; P=0.039). There was no association between percent BMI/excess weight loss and telomere attrition in bariatric patients. Baseline telomere length in bariatric patients was inversely associated with baseline plasma cholesterol and triglyceride concentrations. Telomere shortening was associated with lower high-density lipoprotein cholesterol and higher fasting glucose concentration at baseline in bariatric patients. CONCLUSIONS Increases in relative telomere length were found after bariatric surgery in the long term, presumably due to amelioration of metabolic traits. This may overrule the influence of age and baseline telomere length and facilitate telomere protection in patients experiencing pronounced weight loss.

The Benefits of Intravenous Thrombolysis Relate to the Site of Baseline Arterial Occlusion in the Echoplanar Imaging Thrombolytic Evaluation Trial (EPITHET)

In ischemic stroke, the site of arterial obstruction has been shown to influence recanalization and clinical outcomes. However, this has not been studied in randomized controlled trials, nor has the impact of arterial obstruction site on reperfusion and infarct growth been assessed. We studied the influence of site and degree of arterial obstruction patients enrolled in the Echoplanar Imaging Thrombolytic Evaluation Trial (EPITHET).

Two-dimensional linear-combination model fitting of magnetic resonance spectra to define the macromolecule baseline using FiTAID, a Fitting Tool for Arrays of Interrelated Datasets

To propose the determination of the macromolecular baseline (MMBL) in clinical 1H MR spectra based on T(1) and T(2) differentiation using 2D fitting in FiTAID, a general Fitting Tool for Arrays of Interrelated Datasets.

Single-shot electron bunch length measurements using a spatial electro-optical autocorrelation interferometer

A spatial, electro-optical autocorrelation (EOA) interferometer using the vertically polarized lobes of coherent transition radiation (CTR) has been developed as a single-shot electron bunch length monitor at an optical beam port downstream the 100 MeV preinjector LINAC of the Swiss Light Source. This EOA monitor combines the advantages of step-scan interferometers (high temporal resolution) [D. Mihalcea et al., Phys. Rev. ST Accel. Beams 9, 082801 (2006) and T. Takahashi and K. Takami, Infrared Phys. Technol. 51, 363 (2008)] and terahertz-gating technologies [U. Schmidhammer et al., Appl. Phys. B: Lasers Opt. 94, 95 (2009) and B. Steffen et al., Phys. Rev. ST Accel. Beams 12, 032802 (2009)] (fast response), providing the possibility to tune the accelerator with an online bunch length diagnostics. While a proof of principle of the spatial interferometer was achieved by step-scan measurements with far-infrared detectors, the single-shot capability of the monitor has been demonstrated by electro-optical correlation of the spatial CTR interference pattern with fairly long (500 ps) neodymium-doped yttrium aluminum garnet (Nd:YAG) laser pulses in a ZnTe crystal. In single-shot operation, variations of the bunch length between 1.5 and 4 ps due to different phase settings of the LINAC bunching cavities have been measured with subpicosecond time resolution.

Gunshot energy transfer profile in ballistic gelatine, determined with computed tomography using the total crack length method

By measuring the total crack lengths (TCL) along a gunshot wound channel simulated in ordnance gelatine, one can calculate the energy transferred by a projectile to the surrounding tissue along its course. Visual quantitative TCL analysis of cut slices in ordnance gelatine blocks is unreliable due to the poor visibility of cracks and the likely introduction of secondary cracks resulting from slicing. Furthermore, gelatine TCL patterns are difficult to preserve because of the deterioration of the internal structures of gelatine with age and the tendency of gelatine to decompose. By contrast, using computed tomography (CT) software for TCL analysis in gelatine, cracks on 1-cm thick slices can be easily detected, measured and preserved. In this, experiment CT TCL analyses were applied to gunshots fired into gelatine blocks by three different ammunition types (9-mm Luger full metal jacket, .44 Remington Magnum semi-jacketed hollow point and 7.62 × 51 RWS Cone-Point). The resulting TCL curves reflected the three projectiles' capacity to transfer energy to the surrounding tissue very accurately and showed clearly the typical energy transfer differences. We believe that CT is a useful tool in evaluating gunshot wound profiles using the TCL method and is indeed superior to conventional methods applying physical slicing of the gelatine.

EPITHET: Positive Result After Reanalysis Using Baseline Diffusion-Weighted Imaging/Perfusion-Weighted Imaging Co-Registration

the Echoplanar Imaging Thrombolytic Evaluation Trial (EPITHET) was a prospective, randomized, double-blinded, placebo-controlled, phase II trial of alteplase between 3 and 6 hours after stroke onset. The primary outcome of infarct growth attenuation on MRI with alteplase in mismatch patients was negative when mismatch volumes were assessed volumetrically, without coregistration, which underestimates mismatch volumes. We hypothesized that assessing the extent of mismatch by coregistration of perfusion and diffusion MRI maps may more accurately allow the effects of alteplase vs placebo to be evaluated.

Early non-invasive cardiac output monitoring in hemodynamically unstable intensive care patients: A multi-center randomized controlled trial

Introduction Acute hemodynamic instability increases morbidity and mortality. We investigated whether early non-invasive cardiac output monitoring enhances hemodynamic stabilization and improves outcome. Methods A multicenter, randomized controlled trial was conducted in three European university hospital intensive care units in 2006 and 2007. A total of 388 hemodynamically unstable patients identified during their first six hours in the intensive care unit (ICU) were randomized to receive either non-invasive cardiac output monitoring for 24 hrs (minimally invasive cardiac output/MICO group; n = 201) or usual care (control group; n = 187). The main outcome measure was the proportion of patients achieving hemodynamic stability within six hours of starting the study. Results The number of hemodynamic instability criteria at baseline (MICO group mean 2.0 (SD 1.0), control group 1.8 (1.0); P = .06) and severity of illness (SAPS II score; MICO group 48 (18), control group 48 (15); P = .86)) were similar. At 6 hrs, 45 patients (22%) in the MICO group and 52 patients (28%) in the control group were hemodynamically stable (mean difference 5%; 95% confidence interval of the difference -3 to 14%; P = .24). Hemodynamic support with fluids and vasoactive drugs, and pulmonary artery catheter use (MICO group: 19%, control group: 26%; P = .11) were similar in the two groups. The median length of ICU stay was 2.0 (interquartile range 1.2 to 4.6) days in the MICO group and 2.5 (1.1 to 5.0) days in the control group (P = .38). The hospital mortality was 26% in the MICO group and 21% in the control group (P = .34). Conclusions Minimally-invasive cardiac output monitoring added to usual care does not facilitate early hemodynamic stabilization in the ICU, nor does it alter the hemodynamic support or outcome. Our results emphasize the need to evaluate technologies used to measure stroke volume and cardiac output--especially their impact on the process of care--before any large-scale outcome studies are attempted.

Precision of endodontic working length measurements: a pilot investigation comparing cone-beam computed tomography scanning with standard measurement techniques

The objective of this pilot investigation was to evaluate the utility and precision of already existing limited cone-beam computed tomography (CBCT) scans in measuring the endodontic working length, and to compare it with standard clinical procedures.

Endodontic working length measurement with preexisting cone-beam computed tomography scanning: a prospective, controlled clinical study

The determination of root canal length is a significant outcome predictor for endodontic treatments. The aim of this prospective, controlled clinical study was to analyze endodontic working length measurements in preexisting cone-beam computed tomography (CBCT) scans and to compare them with clinical root canal length determination by using an electronic apex locator (EAL).

The word-length effect in acquired alexia, and real and virtual hemianopia

A word-length effect is often described in pure alexia, with reading time proportional to the number of letters in a word. Given the frequent association of right hemianopia with pure alexia, it is uncertain whether and how much of the word-length effect may be attributable to the hemifield loss. To isolate the contribution of the visual field defect, we simulated hemianopia in healthy subjects with a gaze-contingent paradigm during an eye-tracking experiment. We found a minimal word-length effect of 14 ms/letter for full-field viewing, which increased to 38 ms/letter in right hemianopia and to 31 ms/letter in left hemianopia. We found a correlation between mean reading time and the slope of the word-length effect in hemianopic conditions. The 95% upper prediction limits for the word-length effect were 51 ms/letter in subjects with full visual fields and 161 ms/letter with simulated right hemianopia. These limits, which can be considered diagnostic criteria for an alexic word-length effect, were consistent with the reading performance of six patients with diagnoses based independently on perimetric and imaging data: two patients with probable hemianopic dyslexia, and four with alexia and lesions of the left fusiform gyrus, two with and two without hemianopia. Two of these patients also showed reduction of the word-length effect over months, one with and one without a reading rehabilitation program. Our findings clarify the magnitude of the word-length effect that originates from hemianopia alone, and show that the criteria for a word-length effect indicative of alexia differ according to the degree of associated hemifield loss.