Genicular Nerve Block for Pain Management in Patients With Knee Osteoarthritis: A Randomized Placebo-Controlled Trial.

OBJECTIVE: This study was undertaken to determine the efficacy of ultrasound-guided genicular nerve block (GNB) for the management of knee pain in patients with knee osteoarthritis. METHODS: We performed a 12-week parallel-group, placebo-controlled randomized trial of GNB. Within 2 weeks of randomization, patients with knee osteoarthritis in the active arm received 3 injections of 5.7 mg celestone chronodose (1 ml) and 0.5% bupivacaine (3 ml) to the inferomedial, superomedial, and superolateral genicular nerves; patients with knee osteoarthritis in the placebo arm received injections of normal saline. At baseline and at weeks 2, 4, 8, and 12, patients recorded their pain and disability on a 100-mm visual analog scale (VAS) (the primary outcome measure), the Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC), and the Intermittent and Constant Osteoarthritis Pain scale. Statistical significance was set at a 2-sided Type I error of α = 0.0125 for comparisons at each of the 4 time points. We used a global perceived effect scale to measure patient satisfaction. RESULTS: The 59 patients (36 female, 23 male) who completed the trial had a mean ± SD age of 68.2 ± 8.6 years. Patients in the active group reported improvements in pain scores at 2, 4, 8, and 12 weeks with a diminution of the effect over time. VAS scores at baseline and at weeks 2, 4, 8, and 12 in the active group (n = 31) versus placebo group (n = 28) were 6.2 versus 5.3 (P = 0.294), 2.7 versus 4.7 (P < 0.001), 3.2 versus 5.1 (P < 0.001), 3.9 versus 4.9 (P < 0.001), and 4.6 versus 5.1 (P = 0.055), respectively. Total WOMAC scores at baseline and at weeks 2, 4, 6, 8, and 12 in the active group versus the placebo group were 54.5 versus 48.1 (P = 0.177), 32.9 versus 44.4 (P < 0.001), 33.7 versus 45.8 (P < 0.001), 39.2 versus 44.8 (P = 0.001), and 42.65 versus 45.1 (P = 0.012), respectively. CONCLUSION: GNB offers short-term pain relief for knee osteoarthritis.

Endoscopic clipping for gastrointestinal bleeding: emergency and prophylactic indications.

Endoscopic clipping has become a common practice among endoscopists. Several models are available, most frequently being introduced via the working channel of the endoscope (through-the-scope); however, larger clips can also be mounted onto the distal tip of the endoscope (over-the-scope). The main indications for endoclip placement include providing effective mechanical hemostasis for bleeding lesions and allowing endoscopic closure of gastrointestinal perforations. Endoclips can also be used prophylactically after endoscopic resection; however, this practice is still controversial. This review discusses the main indications for endoscopic clipping in the esophagus, stomach, duodenum and colon to manage acute bleeding lesions, and the criteria to be used in the prevention of delayed post-polypectomy bleeding.

Deterministic processes vary during community assembly for ecologically dissimilar taxa.

The continuum hypothesis states that both deterministic and stochastic processes contribute to the assembly of ecological communities. However, the contextual dependency of these processes remains an open question that imposes strong limitations on predictions of community responses to environmental change. Here we measure community and habitat turnover across multiple vertical soil horizons at 183 sites across Scotland for bacteria and fungi, both dominant and functionally vital components of all soils but which differ substantially in their growth habit and dispersal capability. We find that habitat turnover is the primary driver of bacterial community turnover in general, although its importance decreases with increasing isolation and disturbance. Fungal communities, however, exhibit a highly stochastic assembly process, both neutral and non-neutral in nature, largely independent of disturbance. These findings suggest that increased focus on dispersal limitation and biotic interactions are necessary to manage and conserve the key ecosystem services provided by these assemblages.

Identifying qualitative effects of different grazing types on below-ground communities and function in a long-term field experiment.

Herbivory is an important modulator of plant biodiversity and productivity in grasslands, but our understanding of herbivore-induced changes on below-ground processes and communities is limited. Using a long-term (17 years) experimental site, we evaluated impacts of rabbit and invertebrate grazers on some soil functions involved in carbon cycling, microbial diversity, structure and functional composition. Both rabbit and invertebrate grazing impacted soil functions and microbial community structure. All functional community measures (functions, biogeochemical cycling genes, network association between different taxa) were more strongly affected by invertebrate grazers than rabbits. Furthermore, our results suggest that exclusion of invertebrate grazers decreases both microbial biomass and abundance of genes associated with key biogeochemical cycles, and could thus have long-term consequences for ecosystem functions. The mechanism behind these impacts are likely to be driven by both direct effects of grazing altering the pattern of nutrient inputs and by indirect effects through changes in plant species composition. However, we could not entirely discount that the pesticide used to exclude invertebrates may have affected some microbial community measures. Nevertheless, our work illustrates that human activity that affects grazing intensity may affect ecosystem functioning and sustainability, as regulated by multi-trophic interactions between above- and below-ground communities.