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Anuj Shah,1 Jonathan M Hagedorn,2 Usman Latif,3 Ashley Bailey-Classen,4 Nomen Azeem,5 Douglas P Beall,6 Pankaj Mehta,7 Chad Stephens,8 Larry Khoo,9 Timothy Ray Deer10 1Department of Physical Medicine and Rehabilitation, Detroit Medical Center, Detroit, MI, USA; 2Department of Anesthesiology and Perioperative Medicine, Division of Pain Medicine, Mayo Clinic, Rochester, MN, USA; 3Department of Anesthesiology and Pain Medicine, University of Kansas Health System, Kansas City, KS, USA; 4Trinity Pain Medicine Associates, Fort Worth, TX, USA; 5Florida Spine & Pain Specialists, Riverview, FL, USA; 6Comprehensive Specialty Care, Edmond, OK, USA; 7Pain Specialists of Austin and Central Texas Pain Center, Austin, TX, USA; 8Noble Pain Management and Sports Medicine, Southlake, TX, USA; 9The Spine Clinic of Los Angeles, Los Angeles, CA, USA; 10The Spine and Nerve Center of the Virginias, Charleston, WV, USACorrespondence: Anuj Shah, Department of Physical Medicine and Rehabilitation, Detroit Medical Center, 261 Mack Ave, Detroit, MI, 48220, USA, Tel +1 734646-0321, Email Anujshah74@gmail.comIntroduction: Lumbar spinal stenosis (LSS) is a common condition caused by degenerative changes in the lumbar spine with age. LSS is caused by a variety of factors, including degenerative spondylosis and spondylolisthesis. People suffering with LSS experience neurogenic claudication, which causes severe physical limitations, discomfort, and a decrease in quality of life. Less invasive procedures are now being researched to improve the prognosis, success rate, and safety of LSS treatments. Posterior lateral spinal arthrodesis (PLSA) is a new surgical treatment for LSS. This study looks at the procedural and patient safety of PLSA.Materials and methods: This study is a multicenter retrospective analysis of the safety of PLSA who met the clinical indications for PLSA and underwent the procedure at eight interventional spine practices. Data was collected on demographical information, pre-procedural numeric rating scale score (NRS), post-procedural NRS, and complication reporting. Patients who were included had LSS with or without spondylolisthesis and had failed conservative treatments. A descriptive statistical analysis was performed to report the outcomes. Results were reported as mean and standard deviations for continuous outcomes, and frequency (%) for categorical outcomes.Results: This retrospective analysis involved 191 patients and 202 PLSA implants. The majority of patients were male Caucasians with a mean age of 69.2 years and a BMI of 31.1. A large majority of implants were placed at the L4-5 level, and the average pre-procedural NRS was 6.3 while the average post-procedural NRS was 3.1, indicating a 50.8% reduction in pain (p < 0.0001). Two patients reported complications, but they were unrelated to the device or surgical procedure; no infections, device malfunctions, or migrations were reported in the patient cohort.Conclusion: Preliminary results with PLSA implants indicate that it is a safe treatment option for patients with moderate LSS who do not respond to conservative management.Keywords: lumbar spinal stenosis, spondylolisthesis, interspinous fusion, Minuteman, spinal simplicity, posterior lateral spinal arthrodesis

Abstract Background Whole airway wall thickening on high resolution computed tomography (HRCT) is reported to parallel thickening of the bronchial epithelial reticular basement membrane (RBM) in adult asthmatics. A similar relationship in children with difficult asthma (DA), in whom RBM thickening is a known feature, may allow the use of HRCT as a non-invasive marker of airway remodelling. We evaluated this relationship in children with DA. Methods 27 children (median age 10.5 [range 4.1–16.7] years) with DA, underwent endobronchial biopsy from the right lower lobe and HRCT less than 4 months apart. HRCTs were assessed for bronchial wall thickening (BWT) of the right lower lobe using semi-quantitative and quantitative scoring techniques. The semi-quantitative score (grade 0–4) was an overall assessment of BWT of all clearly identifiable airways in HRCT scans. The quantitative score (BWT %; defined as [airway outer diameter – airway lumen diameter]/airway outer diameter ×100) was the average score of all airways visible and calculated using electronic endpoint callipers. RBM thickness in endobronchial biopsies was measured using image analysis. 23/27 subjects performed spirometry and the relationships between RBM thickness and BWT with airflow obstruction evaluated. Results Median RBM thickness in endobronchial biopsies was 6.7(range 4.6 – 10.0) μm. Median qualitative score for BWT of the right lower lobe was 1(range 0 – 1.5) and quantitative score was 54.3 (range 48.2 – 65.6)%. There was no relationship between RBM thickness and BWT in the right lower lobe using either scoring technique. No relationship was found between FEV1 and BWT or RBM thickness. Conclusion Although a relationship between RBM thickness and BWT on HRCT has been found in adults with asthma, this relationship does not appear to hold true in children with DA.

Electrons in Earth's outer radiation belt are highly dynamic, with fluxes changing by up to orders of magnitude. The penetration of electrons from the outer belt to the inner belt is one such change observed during geomagnetic storms and was previously observed in electrons up to 1 MeV for some strong storms observed by the Van Allen Probes. We analyze pulse height analysis data from the Relativistic Electric and Proton Telescope (REPT) on the Van Allen Probes to produce electron flux measurements with lower minimum energy and significantly improved resolution compared to the standard REPT data and show that electron penetrations into the inner belt (L ≤ 2) extend to at least 1.3 MeV and penetrations into the slot region (2 < L < 2.8) extend to at least 1.5 MeV during certain geomagnetic storms. We also demonstrate that these penetrations are associated with butterfly pitch angle distributions from 1 to 1.3 MeV. Plain Language Summary: Electrons in Earth's outer radiation belt are highly dynamic with the amount and energy of them changing drastically, especially during geomagnetic storms. The penetration of electrons from the outer belt to the inner radiation belt is one such change and was previously observed in electrons with energies ≤1 MeV during some of the strongest storms during the Van Allen Probes mission. Electrons in the radiation belts also have a pitch angle that describes what portion of their motion is along or perpendicular to the direction of the magnetic field. Pitch angle distributions (PAD) are often used to gain information on the dynamics of the electrons, as unstable distributions can be caused by and indicative of wave activity that cannot always be measured directly. PADs with a minimum at 90°, called butterfly PADs, are one such unstable distribution that have previously been observed in penetrating electrons with energies ∼100–900 keV. We use instrument simulation to analyze data from the Van Allen Probes that could not previously be analyzed to show that the maximum energy of these penetrations is higher than previously observed, up to 1.3 MeV, and that these penetrations are associated with butterfly PADs at 1–1.3 MeV. Key Points: REPT PHA data can be used to produce high energy resolution flux spectra of >1 MeV electronsElectron penetrations below L = 2 during strong geomagnetic storms extend in energy up to 1.3 MeVElectron penetrations below L = 2 at energies 1–1.3 MeV are associated with butterfly pitch angle distributions [ABSTRACT FROM AUTHOR]