A systematic review of postoperative outcomes of kidney stone surgery and meta-analysis of outcomes of percutaneous nephrolithotomy in individuals with spinal cord injury.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVES: To evaluate outcomes of surgical treatment for nephrolithiasis in individuals with spinal cord injury (SCI). METHODS: We systematically reviewed the Ovid MEDLINE, Embase, CENTRAL, and Web of Science databases for studies examining outcomes of kidney stone procedures in individuals with SCI. Our primary outcomes were stone-free rate (SFR) and complications as categorized by Clavien-Dindo classification. A meta-analysis of comparative studies was performed to assess differences in SFR and complication rate between individuals with and without SCI following PCNL. RESULTS: A total of 27 retrospective and observational articles were included. Interventions for kidney stones included PCNL, shockwave lithotripsy (SWL), and ureteroscopy. Pooled SFR in individuals with SCI was 54%, for SWL, 74% for PCNL, and 36% for ureteroscopy. Meta-analyses found that there was higher rate of grades I (OR 9.54; 95% CI, 3.06 to 29.79), II (OR 3.38; 95% CI, 1.85 to 6.18), and III-V (OR 2.38; 95% CI, 1.35 to 4.19) complications in individuals with SCI compared to non-SCI individuals following PCNL. The rate of infectious complications was also higher in individuals with SCI (OR 6.15; 95% CI, 1.86 to 20.39). However, there was no difference in SFR (OR 0.64; 95% CI, 0.15 to 2.64) between groups. CONCLUSIONS: Individuals with SCI are at higher risk of minor, major, and infectious complications following PCNL compared to non-SCI individuals. There was no significant difference between groups in SFR following PCNL, suggesting that PCNL is an effective surgery for kidney stones in individuals with SCI.

Creation and preclinical evaluation of a novel mussel-inspired, biomimetic, bioactive bone graft scaffold: direct comparison with Infuse bone graft using a rat model of spinal fusion.

OBJECTIVE: Infuse bone graft is a widely used osteoinductive adjuvant; however, the simple collagen sponge scaffold used in the implant has minimal inherent osteoinductive properties and poorly controls the delivery of the adsorbed recombinant human bone morphogenetic protein-2 (rhBMP-2). In this study, the authors sought to create a novel bone graft substitute material that overcomes the limitations of Infuse and compare the ability of this material with that of Infuse to facilitate union following spine surgery in a clinically translatable rat model of spinal fusion. METHODS: The authors created a polydopamine (PDA)-infused, porous, homogeneously dispersed solid mixture of extracellular matrix and calcium phosphates (BioMim-PDA) and then compared the efficacy of this material directly with Infuse in the setting of different concentrations of rhBMP-2 using a rat model of spinal fusion. Sixty male Sprague Dawley rats were randomly assigned to each of six equal groups: 1) collagen + 0.2 µg rhBMP-2/side, 2) BioMim-PDA + 0.2 µg rhBMP-2/side, 3) collagen + 2.0 µg rhBMP-2/side, 4) BioMim-PDA + 2.0 µg rhBMP-2/side, 5) collagen + 20 µg rhBMP-2/side, and 6) BioMim-PDA + 20 µg rhBMP-2/side. All animals underwent posterolateral intertransverse process fusion at L4-5 using the assigned bone graft. Animals were euthanized 8 weeks postoperatively, and their lumbar spines were analyzed via microcomputed tomography (µCT) and histology. Spinal fusion was defined as continuous bridging bone bilaterally across the fusion site evaluated via µCT. RESULTS: The fusion rate was 100% in all groups except group 1 (70%) and group 4 (90%). Use of BioMim-PDA with 0.2 µg rhBMP-2 led to significantly greater results for bone volume (BV), percentage BV, and trabecular number, as well as significantly smaller trabecular separation, compared with the use of the collagen sponge with 2.0 µg rhBMP-2. The same results were observed when the use of BioMim-PDA with 2.0 µg rhBMP-2 was compared with the use of the collagen sponge with 20 µg rhBMP-2. CONCLUSIONS: Implantation of rhBMP-2-adsorbed BioMim-PDA scaffolds resulted in BV and bone quality superior to that afforded by treatment with rhBMP-2 concentrations 10-fold higher implanted on a conventional collagen sponge. Using BioMim-PDA (vs a collagen sponge) for rhBMP-2 delivery could significantly lower the amount of rhBMP-2 required for successful bone grafting clinically, improving device safety and decreasing costs.

Bonding and Suppression of a Magnetic Phase Transition in EuMn2P2.

Electrons in solids often adopt complex patterns of chemical bonding driven by the competition between energy gains from covalency and delocalization, and energy costs of double occupation to satisfy Pauli exclusion, with multiple intermediate states in the transition between highly localized, and magnetic, and delocalized, and nonmagnetic limits. Herein, we report a chemical pressure-driven transition from a proper Mn magnetic ordering phase transition to a Mn magnetic phase crossover in EuMn2P2 the limiting end member of the EuMn2X2 (X = Sb, As, P) family of layered materials. This loss of a magnetic ordering occurs despite EuMn2P2 remaining an insulator at all temperatures, and with a phase transition to long-range Eu antiferromagnetic order at TN ≈ 17 K. The absence of a Mn magnetic phase transition contrasts with the formation of long-range Mn order at T ≈ 130 K in isoelectronic EuMn2Sb2 and EuMn2As2. Temperature-dependent specific heat and 31P NMR measurements provide evidence for the development of short-range Mn magnetic correlations from T ≈ 250-100 K, interpreted as a precursor to covalent bond formation. Density functional theory calculations demonstrate an unusual sensitivity of the band structure to the details of the imposed Mn and Eu magnetic order, with an antiferromagnetic Mn arrangement required to recapitulate an insulating state. Our results imply a picture in which long-range Mn magnetic order is suppressed by chemical pressure, but that antiferromagnetic correlations persist, narrowing bands and producing an insulating state.

Reduction of opioid use after orthopedic surgery: a scoping review.

BACKGROUND: The opioid epidemic is one of the biggest public health crises of our time, and overprescribing of opioids after surgery has the potential to lead to long-term use. The purpose of this review was to identify and summarize the available evidence on interventions aimed at reducing opioid use after orthopedic surgery. METHODS: We searched CENTRAL, Embase and Medline from inception until August 2019 for studies comparing interventions aimed at reducing opioid use after orthopedic surgery to a control group. We recorded demographic data and data on intervention success, and recorded or calculated percent opioid reduction compared to control. RESULTS: We included 141 studies (20 963 patients) in the review, of which 113 (80.1%) were randomized controlled trials (RCTs), 6 (4.3%) were prospective cohort studies, 16 (11.4%) were retrospective cohort studies, 5 (3.6%) were case reports, and 1 (0.7%) was a case series. The majority of studies (95 [67.4%]) had a follow-up duration of 2 days or less. Interventions included the use of local anesthetics and/or nerve blocks (42 studies [29.8%]), nonsteroidal anti-inflammatory drugs (31 [22.0%]), neuropathic pain medications (9 [6.4%]) and multimodal analgesic combinations (25 [17.7%]. In 127 studies (90.1%), a significant decrease in postoperative opioid consumption compared to the control intervention was reported; the median opioid reduction in these studies was 39.7% (range 5%-100%). Despite these reductions in opioid use, the effect on pain scores and on incidence of adverse effects was inconsistent. CONCLUSION: There is a large body of evidence from randomized trials showing the promise of a variety of interventions for reducing opioid use after orthopedic surgery. Rigorously designed RCTs are needed to determine the ideal interventions or combination of interventions for reducing opioid use, for the good of patients, medicine and society.

Twisting of 2D Kagomé Sheets in Layered Intermetallics.

Chemical bonding in 2D layered materials and van der Waals solids is central to understanding and harnessing their unique electronic, magnetic, optical, thermal, and superconducting properties. Here, we report the discovery of spontaneous, bidirectional, bilayer twisting (twist angle ∼4.5°) in the metallic kagomé MgCo6Ge6 at T = 100(2) K via X-ray diffraction measurements, enabled by the preparation of single crystals by the Laser Bridgman method. Despite the appearance of static twisting on cooling from T ∼300 to 100 K, no evidence for a phase transition was found in physical property measurements. Combined with the presence of an Einstein phonon mode contribution in the specific heat, this implies that the twisting exists at all temperatures but is thermally fluctuating at room temperature. Crystal Orbital Hamilton Population analysis demonstrates that the cooperative twisting between layers stabilizes the Co-kagomé network when coupled to strongly bonded and rigid (Ge2) dimers that connect adjacent layers. Further modeling of the displacive disorder in the crystal structure shows the presence of a second, Mg-deficient, stacking sequence. This alternative stacking sequence also exhibits interlayer twisting, but with a different pattern, consistent with the change in electron count due to the removal of Mg. Magnetization, resistivity, and low-temperature specific heat measurements are all consistent with a Pauli paramagnetic, strongly correlated metal. Our results provide crucial insight into how chemical concepts lead to interesting electronic structures and behaviors in layered materials.

Exploring ligand non-innocence of coordinatively-versatile diamidodipyrrinato cobalt complexes.

The non-innocence of diamidodipyrrin is explored in a series of cobaltous complexes with novel binding motifs. By varying the coordination modes, a reversible one-electron reduction is remarkably shifted by nearly 200 mV in a single metal-ligand platform. Our study illustrates a new strategy for modifying the redox activity of porphyrin-like scaffolds.