68 research outputs found

    Tectonic control on the petrophysical properties of foredeep sandstone in the Central Apennines, Italy

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    Petrophysical properties of rocks and their applicability at larger scale are a challenging topic in Earth sciences. Petrophysical properties of rocks are severely affected by boundary conditions, rock fabric/microstructure, and tectonics that require a multiscale approach to be properly defined. Here we (1) report laboratory measurements of density, porosity, permeability, and P wave velocities at increasing confining pressure conducted on Miocene foredeep sandstones (Frosinone Formation); (2) compare the laboratory results with larger-scale geophysical investigations; and (3) discuss the effect of thrusting on the properties of sandstones. At ambient pressure, laboratory porosity varied from 2.2% to 13.8% and P wave velocities (Vp) from 1.5 km/s to 2.7 km/s. The P wave velocity increased with confining pressure, reaching between 3.3 km/s and 4.7 km/s at 100 MPa. In situ Vp profiles, measured using sonic logs, matched the ultrasonic laboratory measurement well. The permeability varied between 1.4 × 10 15m2 and 3.9 × 10 15m2 and was positively correlated with porosity. The porosity and permeability of samples taken at various distances to the Olevano–Antrodoco fault plane progressively decreased with distance while P wave velocity increased. At about 1 km from the fault plane, the relative variations reached 43%, 65%, and 20% for porosity, permeability, and P wave velocity, respectively. This suggests that tectonic loading changed the petrophysical properties inherited from sedimentation and diagenesis. Using field constraints and assuming overburden-related inelastic compaction in the proximity of the fault plane, we conclude that the fault reached the mechanical condition for rupture in compression at differential stress of 64.8 MPa at a depth of 1500 m

    Adaptive proximal scaphoid implant (APSI): a systematic review of the literature

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    Scapholunate advanced collapse collapse (SLAC) is a challenging topic for hand surgeons. The adaptative proximal scaphoid implant (APSI) (Bioprofile-Tornier) is a pyrocarbon ovoid shaped interpositional implant, that allows adaptive mobility during motion. The aim of this systematic review is to analyze the clinical and radiological outcomes of APSI implants and possible complications. We performed a literature search combining the following key-words: “APSI”, “Scaphoid’s proximal pole”, “implant”, “scaphoid avascular necrosis”, “SLAC”, “SNAC”, “pyrocarbon”, “prosthesis”, and “spacer” with no limitations for year of publication. We selected seven studies considered relevant to our systematic review. All studies described an improvement in the grip strength and the flexion extension arch compared to pre-operative values. The percentage of patients who reported progression of osteoarthritis (OA) with APSI was 17.3%, and implant’s mobilization has a rate 5.1% (8/156). In conclusion the APSI implant is a reliable alternative for the treatment of SNAC wrist and SLAC wrist

    Chronic exertional compartment syndrome of the forearm: a systematic review

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    The aim of this systematic review is to understand which surgical procedure provides better results in terms of pain relief and function in the treatment of chronic exertional compartment syndrome (CECS) of the forearm. We searched Medline (PubMed), Web of Science, Embase and Scopus databases on 8 July 2020. Twelve studies were included in this review. We assessed the quality of the studies using the Coleman Methodological Score. Data on demographic features, operative readings, diagnostic methods, follow-up periods, type and rates of complications, survivorship of the procedure, return to sport activity, and outcome measures were recorded. In conclusion, compared to the other techniques, endoscopic fasciotomy delivers similar success rates and lower incidence of complications

    Ermutigende Ergebnisse nach Pyrokarbon-Interpositionsarthroplastik bei Rhizarthrose

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    Chronic Exertional Compartment Syndrome of the Forearm: Mini-invasive Technique Using an Endoscopic Soft Tissue Release System

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    Chronic exertional compartment syndrome of the forearm is a rare disease characterized by the recurrent onset of forearm pain and progressive weakness during exertion. Over the years many surgical techniques have been reported in literature: wide-open fasciotomy, mini-open fasciotomy, fasciotomy associated with fasciectomy, and mini-invasive endoscopic fasciotomy. Compared with traditional open techniques, mini-invasive techniques are characterized by minimal tissue trauma, less postoperative pain, faster recovery to normal activity and better esthetical result. We describe a mini-invasive endoscopic technique for the treatment of forearm chronic exertional compartment syndrome using the SmartRelease endoscopic tissue release system (MicroAire)

    Treatment of Proximal Scaphoid Non-union by Resection of the Proximal Pole and Palmaris Longus Interposition Arthroplasty

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    The purpose of this study was to determine the long-term clinical and radiographic outcome in a group of patients treated with resection of the proximal pole and tendon ball arthroplasty because of a scaphoid non-union
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