Nailing precision: a systematic review and meta-analysis of randomized controlled trials comparing piriformis and trochanteric entry points for femoral antegrade nailing.

INTRODUCTION: Entry point selection, a crucial aspect of femoral antegrade nailing, can impact nail fit and consequently fracture reduction. In adults, the standard entry portals used are the piriformis fossa and the tip of the greater trochanter. Previous systematic reviews comparing the two techniques have not been limited to Randomized Controlled Trials (RCTs) and have not consistently included the same available RCTs. MATERIALS AND METHODS: A systematic search of comparative studies regarding entry portal selection in femoral antegrade nailing was conducted on seven databases. Only Prospective RCTs comparing trochanteric and piriformis entry in the management of trochanteric or diaphyseal femur fractures were eligible for inclusion. RESULTS: Ultimately, only 6 RCTs were found eligible for inclusion. Five of the six included studies reported on operative time. The resulting mean difference (MD) illustrated a significant decrease in operative time by approximately 21.26 min (95% CI - 28.60 to - 13.92, p < 0.001) using trochanteric entry. Fluoroscopy exposure was reported on by four studies, however, only two studies were included in the analysis due to different reporting methods. Trochanteric entry used significantly less fluoroscopy than piriformis entry (MD -50.33 s, 95% CI - 84.441 to - 16.22, p = 0. 004). No significant difference in malalignment rates, delayed union rates, nonunion rates, pain scores, or complication rates was found. CONCLUSION: The significant differences found in operating time and fluoroscopy time align with those in other studies. While we were not able to pool the data on functional outcome scores, none of the included studies found a significant difference in scores by their last follow-up. Both approaches demonstrate comparable functional outcomes and safety profiles, indicating the choice of entry point should be at the discretion of the surgeon based on technique familiarity and fracture characteristics.

Syndesmotic screws, unscrew them, or leave them? A systematic review and meta-analysis of randomized controlled trials.

Background: Syndesmotic injuries are frequently stabilized using syndesmotic screws. Traditionally, these screws were routinely removed during the postoperative period, however recent literature has brought into question the necessity of routine removal, citing no change in functional outcomes and the inherent risks of a second surgery. Our study aimed to compare outcomes of patients undergoing routine syndesmotic screw removal versus those undergoing an on-demand approach to removal. Methods: A systematic search of studies comparing routine syndesmotic screw removal to on-demand screw removal following an acute ankle fracture, or an isolated syndesmotic injury was conducted across seven databases. Only Prospective randomized controlled trials were eligible for inclusion. Data reported on by at least 2 studies was pooled for analysis. Results: Three studies were identified that met inclusion and exclusion criteria. No significant difference in Olerud-Molander Ankle Score (MD -2.36, 95% CI -6.50 to 1.78, p = 0.26), American Orthopedic Foot and Ankle Hindfoot Score (MD -0.45, 95% CI -1.59 to .69, p = 0.44), or dorsiflexion (MD 2.20, 95% CI -0.50 to 4.89, p = 0.11) was found between the routine removal group and on-demand removal group at 1-year postoperatively. Routine removal was associated with a significantly higher rate of complications than on-demand removal (RR 3.02, 95% CI 1.64 to 5.54, p = 0.0004). None of the included studies found significant differences in pain scores or range of motion by 1-year postoperatively. Conclusion: Given the increased risk of complications with routine syndesmotic screw removal and the comparable outcomes when screws are retained, an as-needed approach to syndesmotic screw removal should be considered.

Trophic ecology of the invasive argentine ant: spatio-temporal variation in resource assimilation and isotopic enrichment.

Studies of food webs often employ stable isotopic approaches to infer trophic position and interaction strength without consideration of spatio-temporal variation in resource assimilation by constituent species. Using results from laboratory diet manipulations and monthly sampling of field populations, we illustrate how nitrogen isotopes may be used to quantify spatio-temporal variation in resource assimilation in ants. First, we determined nitrogen enrichment using a controlled laboratory experiment with the invasive Argentine ant (Linepithema humile). After 12 weeks, worker δ(15)N values from colonies fed an animal-based diet had δ(15)N values that were 5.51% greater compared to colonies fed a plant-based diet. The shift in δ(15)N values in response to the experimental diet occurred within 10 weeks. We next reared Argentine ant colonies with or without access to honeydew-producing aphids and found that after 8 weeks workers from colonies without access to aphids had δ(15)N values that were 6.31% larger compared to colonies with access to honeydew. Second, we sampled field populations over a 1-year period to quantify spatio-temporal variability in isotopic ratios of L. humile and those of a common native ant (Solenopsis xyloni). Samples from free-living colonies revealed that fluctuations in δ(15)N were 1.6-2.4‰ for L. humile and 1.8-2.9‰ for S. xyloni. Variation was also detected among L. humile castes: time averaged means of δ(15)N varied from 1.2 to 2.5‰ depending on the site, with δ(15)N values for queens ≥ workers > brood. The estimated trophic positions of L. humile and S. xyloni were similar within a site; however, trophic position for each species differed significantly at larger spatial scales. While stable isotopes are clearly useful for examining the trophic ecology of arthropod communities, our results suggest that caution is warranted when making ecological interpretations when stable isotope collections come from single time periods or life stages.