Clinical Outcomes of Intermediate-Length Cephalomedullary Nails for Intertrochanteric Femur Fracture Repair in Older Adults

Introduction. Hip fracture is a major cause of morbidity and mortality in older adults. Intertrochanteric hip fractures often are treated surgically using cephalomedullary nails (CMN), in either a short or long length. Their outcomes are documented in the literature; however, outcomes of the intermediate-length CMN have not been well described. Methods. A retrospective review was conducted of older adults with intertrochanteric hip fractures that were treated with cephalomedullary nail fixation using an intermediate-length (235 mm Synthes Trochanteric Fixation® nail or 240 mm Stryker Gamma 3®) nail. Outcome data were collected during the inpatient stay and 16 months post-operatively. Results. Seventy-seven patients met inclusion criteria and were reviewed during inpatient stay; however, only 42 had documented post-operative outcomes. Of those, two patients died post-discharge and were not included in the 16-month follow-up. Comparison of results to published literature suggested that intermediate-length nails are comparable to short-length nails with regard to time in the operating room and estimated blood loss. The rate of blood transfusion was lower and length of hospital stay was shorter than in comparable studies of both short- and long-length nails. There were no post-operative periprosthetic fractures in the 16-month follow-up. This rate was lower than published rates for short and long nails. The hardware failure rate (3/42, 7.1%) of intermediate-length nails was higher than comparison studies of both short- and long-length nails.    Conclusions. Patient outcomes for intermediate-length nails were similar to outcomes of shorter length nails. Utilization of the intermediate-length nail appears to be an effective treatment option for repair of intertrochanteric femur fractures. However, direct comparison is difficult since periprosthetic fracture rate may increase over time and nail length and hardware failure are not defined consistently in the literature.  Further study is needed with a larger sample size followed over a longer period of time to confirm our findings

Ecotypes of an ecologically dominant prairie grass (\u3ci\u3eAndropogon gerardii\u3c/i\u3e) exhibit genetic divergence across the U.S. Midwest grasslands’ environmental gradient

Big bluestem (Andropogon gerardii) is an ecologically dominant grass with wide distribution across the environmental gradient of U.S. Midwest grasslands. This system offers an ideal natural laboratory to study population divergence and adaptation in spatially varying climates. Objectives were to: (i) characterize neutral genetic diversity and structure within and among three regional ecotypes derived from 11 prairies across the U.S. Midwest environmental gradient, (ii) distinguish between the relative roles of isolation by distance (IBD) vs. isolation by environment (IBE) on ecotype divergence, (iii) identify outlier loci under selection and (iv) assess the association between outlier loci and climate. Using two primer sets, we genotyped 378 plants at 384 polymorphic AFLP loci across regional ecotypes from central and eastern Kansas and Illinois. Neighbour-joining tree and PCoA revealed strong genetic differentiation between Kansas and Illinois ecotypes, which was better explained by IBE than IBD. We found high genetic variability within prairies (80%) and even fragmented Illinois prairies, surprisingly, contained high within-prairie genetic diversity (92%). Using BAYENV2, 14 topranked outlier loci among ecotypes were associated with temperature and precipitation variables. Six of seven BAYESCAN FST outliers were in common with BAYENV2 outliers. High genetic diversity may enable big bluestem populations to better withstand changing climates; however, population divergence supports the use of local ecotypes in grassland restoration. Knowledge of genetic variation in this ecological dominant and other grassland species will be critical to understanding grassland response and restoration challenges in the face of a changing climate

Data from: Ecotypes of an ecologically dominant prairie grass (Andropogon gerardii) exhibit genetic divergence across the U.S. Midwest grasslands environmental gradient

Big bluestem (Andropogon gerardii) is an ecologically dominant grass with wide distribution across the environmental gradient of U.S. Midwest grasslands. This system offers an ideal natural laboratory to study the nature of population divergence and adaptation in spatially varying climates. Objectives were to: (i) characterize neutral genetic diversity and structure within and among three regional ecotypes derived from 11 prairies across the U.S. Midwest environmental gradient, (ii) distinguish between the relative roles of isolation-by-distance (IBD) vs. isolation-by-environment (IBE) on ecotype divergence, (iii) identify outlier loci under selection, and (iv) assess the association between outlier loci and climate. Using two primer sets, we genotyped 378 plants at 384 polymorphic AFLP loci across regional ecotypes from central and eastern Kansas, and Illinois. Neighbor-joining tree and PCA revealed strong genetic differentiation between Kansas and Illinois ecotypes, which was better explained by IBE than IBD. High genetic variability within prairies was found (80%) and even fragmented Illinois prairies, surprisingly, contain high within-prairie genetic diversity (92%). Using Bayenv2, we identified 14 top-ranked outlier loci among ecotypes to be associated with temperature and precipitation variables. Six of seven BayeScan FST-outliers were also found in common with Bayenv2 outliers. High genetic diversity may enable big bluestem populations to better withstand changing climates; however, population divergence supports the use of local ecotypes in grassland restoration. Knowledge of genetic variation in this ecological dominant and other grassland species will be critical to understanding grassland response and restoration challenges in the face of a changing climate

BAYENV2 Covariance Matrices

Resulting covariance matrices after removing the 14 top-ranked outliers from the 'control loci' data set. Tabs separate each successive covariance matrix. These matrices result from independent runs of 10^6 iterations

BAYENV2 Input File - All Markers

Use this file as the 'control loci' input for BayEnv2. This file is analogous to the 'SNPSFILE' described in BayEnv2

BAYENV2 Input File - Individual AFLP Loci

Allele count data for a single AFLP locus parsed into individual files. Use these 384 AFLP count data as the individual files as analogous to the 'SNPFILE' input data for BayEnv2. Data occur in the same prairie population order that they occur in the covariance matrix and 'bayenv2_aflp_outliersrem.txt' file

AFLP Raw Genotypes

This file contains the AFLP raw genotype scores (1=presence of AFLP band; 0=absence of AFLP band) for each of the 387 AFLP markers scored across 378 big bluestem (Andropogon gerardii) individual plants

STRUCTURE Input Data File by Prairie

Use this file as input into STRUCTURE. Locations labeled by prairie