Minimally invasive presacral approach for revision of an Axial Lumbar Interbody Fusion rod due to fall-related lumbosacral instability: a case report

<p>Abstract</p> <p>Introduction</p> <p>The purpose of this study was to describe procedural details of a minimally invasive presacral approach for revision of an L5-S1 Axial Lumbar Interbody Fusion rod.</p> <p>Case presentation</p> <p>A 70-year-old Caucasian man presented to our facility with marked thoracolumbar scoliosis, osteoarthritic changes characterized by high-grade osteophytes, and significant intervertebral disc collapse and calcification. Our patient required crutches during ambulation and reported intractable axial and radicular pain. Multi-level reconstruction of L1-4 was accomplished with extreme lateral interbody fusion, although focal lumbosacral symptoms persisted due to disc space collapse at L5-S1.</p> <p>Lumbosacral interbody distraction and stabilization was achieved four weeks later with the Axial Lumbar Interbody Fusion System (TranS1 Inc., Wilmington, NC, USA) and rod implantation via an axial presacral approach.</p> <p>Despite symptom resolution following this procedure, our patient suffered a fall six weeks postoperatively with direct sacral impaction resulting in symptom recurrence and loss of L5-S1 distraction. Following seven months of unsuccessful conservative care, a revision of the Axial Lumbar Interbody Fusion rod was performed that utilized the same presacral approach and used a larger diameter implant. Minimal adhesions were encountered upon presacral re-entry. A precise operative trajectory to the base of the previously implanted rod was achieved using fluoroscopic guidance. Surgical removal of the implant was successful with minimal bone resection required. A larger diameter Axial Lumbar Interbody Fusion rod was then implanted and joint distraction was re-established. The radicular symptoms resolved following revision surgery and our patient was ambulating without assistance on post-operative day one. No adverse events were reported.</p> <p>Conclusions</p> <p>The Axial Lumbar Interbody Fusion distraction rod may be revised and replaced with a larger diameter rod using the same presacral approach.</p

Optically induced coherent intra-band dynamics in disordered semiconductors

On the basis of a tight-binding model for a strongly disordered semiconductor with correlated conduction- and valence band disorder a new coherent dynamical intra-band effect is analyzed. For systems that are excited by two, specially designed ultrashort light-pulse sequences delayed by tau relatively to each other echo-like phenomena are predicted to occur. In addition to the inter-band photon echo which shows up at exactly t=2*tau relative to the first pulse, the system responds with two spontaneous intra-band current pulses preceding and following the appearance of the photon echo. The temporal splitting depends on the electron-hole mass ratio. Calculating the population relaxation rate due to Coulomb scattering, it is concluded that the predicted new dynamical effect should be experimentally observable in an interacting and strongly disordered system, such as the Quantum-Coulomb-Glass.Comment: to be published in Physical Review B15 February 200

Intercalated theophylline-smectite hybrid for pH-mediated delivery

On the basis of their large specific surface areas, high adsorption and cation exchange capacities, swelling potential and low toxicity, natural smectite clays are attractive substrates for the gastric protection of neutral and cationic drugs. Theophylline is an amphoteric xanthine derivative that is widely used as a bronchodilator in the treatment of asthma and chronic obstructive pulmonary disease. This study considers the in vitro uptake and release characteristics of the binary theophylline-smectite system. The cationic form of theophylline was readily ion exchanged into smectite clay at pH 1.2 with a maximum uptake of 67±2 mg g−1. Characterisation of the drug-clay hybrid system by powder X-ray diffraction analysis, Fourier transform infrared spectroscopy, differential scanning calorimetry and scanning electron microscopy confirmed that the theophylline had been exclusively intercalated into the clay system in an amorphous form. The drug remained bound within the clay under simulated gastric conditions at pH 1.2; and the prolonged release of approximately 40% of the drug was observed in simulated intestinal fluid at pH 6.8 and 7.4 within a 2-h timeframe. The incomplete reversibility of the intercalation process was attributed to chemisorption of the drug within the clay lattice. These findings indicate that smectite clay is a potentially suitable vehicle for the safe passage of theophylline into the duodenum. Protection from absorption in the stomach and subsequent prolonged release in the small intestine are advantageous in reducing fluctuations in serum concentration which may impact therapeutic effect and toxicit

ICAR: endoscopic skull‐base surgery

n/

Methods of Harvesting Hay Fields and Pastures in Northwestern Washington (North Coast Area), 1945

Topics include: Introduction; Farm Organization and Types of Forage Utilization; Mowing and Curing Methods: Equipment, Rates of Work, and Costs; Making Silage: Crew Equipment, Rates of Work, and Costs; Making Hay: Crew, Equipment, Rates of Work, and Costs; Comparison of Silage-and Hay-Harvesting Method

One hundred years of neurosurgery: contributions of American women.

The end of the first 100 years of any endeavor is an appropriate time to look back and peer forward. As neurosurgery celebrates its 1st century as a specialty, the increasing role of women neurosurgeons is a major theme. This article documents the early women pioneers in neurosurgery. The contributions of these trailblazers to the origins, academics, and professional organizations of neurosurgery are highlighted. The formation of Women in Neurosurgery in 1989 is described, as is the important role this organization has played in introducing and promoting talented women in the profession. Contributions of women neurosurgeons to academic medicine and society as a whole are briefly highlighted. Contemporary efforts and initiatives indicate future directions in which women may lead neurosurgery in its 2nd century

Aktuelle Themen der Kernenergie : Vorträge eines Seminars veranstaltet von der Programmgruppe Technik und Gesellschaft des Forschungszentrums Jülich GmbH

Die Diskussion um die Kernenergie in der Bundesrepublik Deutschland hat sich in denletzten Jahren auf die Schwerpunkte Reaktorsicherheit und Entsorgung konzentriert; verstärktwerden dazu Fragen der Zuverlässigkeit erörtert. Dabei ist die politische Argumentationgegenüber der Beurteilung technischer Sachverhalte immer mehr in den Vordergrundgetreten. Durch den Verzicht auf die Wiederaufarbeitungsanlage Wackersdorf ist die Entsorgungwieder zum Angelpunkt der nuklearen Kontroverse geworden.Der vorliegende Bericht ergänzt und erweitert die grundlegenden Informationen, die im Seminarbericht„Nutzen und Risiko der Kernenergie" (Jül-Conf-17) enthalten sind. Die Beiträgebefassen sich mit der Entsorgung der Kernkraftwerke, den Maßnahmen zur Verhinderungdes Mißbrauchs von Kernbrennstoffen und den Eigenschaften und der Verwendungvon Plutonium; gegenüber der letzten Auflage wurde das Thema „Energie und Umwelt"neu aufgenommen. Auch dieser Bericht entstand im Zusammenhang mit Seminaren, diedie KFA zur Information der Öffentlichkeit veranstaltet. Soweit die hier behandelten Sachgebietenicht durch das Fachwissen eigener Mitarbeiter abgedeckt werden konnten, wurdenExperten aus anderen Forschungseinrichtungen um Mitwirkung gebeten. Die Autorenwaren bemüht, ihr fachliches Wissen allgemein verständlich darzustellen. Einige Beiträgewurden völlig neu geschrieben, die übrigen wurden gründlich überarbeitet und aktualisiert.Für ihren Einsatz bei der Herstellung der Manuskripte danken wir Walburga Beys und GabrieleMacherey.Der Seminarbericht gibt allen an Energiefragen Interessierten die Möglichkeit, sich sachlichzu informieren und damit einen Wissensstand zu erreichen, auf dem eine persönlicheEntscheidung aufbauen kann