Technique to treat iliopsoas irritation after total hip replacement: Thickening of articular hip capsule through an abridged direct anterior approach

AbstractIliopsoas irritation due to acetabular cup component impingement following total hip arthroplasty (THA) is usually treated by infiltration or by distal iliopsoas tenotomy in case of recurrence; however, this can result in an active flexion deficit of the thigh. To prevent this complication, we developed an original technique that we performed between 2012 and 2014 in patients with recurrent impingement following extraarticular corticosteroid injections. This included 5 patients (mean age: 64 [53–75] years old) in whom we performed an ambulatory bursectomy by the Hueter approach and placed a polyglactin 910 (Vicryl™) mesh plate on the entire anterior hip capsule. After a mean follow-up of 12months (9–29months), anterior pain had decreased in all patients with improvement and an increase in the Oxford-12 (mean: 15 points [10–19]), Merle d’Aubigné (mean: 2.5 points [1–5]) and Harris (mean: 18 points [10–29]) scores. No flexion deficits were observed. An infected postoperative hematoma had to be drained but was cured at follow-up. This simple procedure provides satisfactory results and preserves THA function. It does not jeopardize future procedures and is an alternative option in case of unsuccessful conservative treatment

Recovery of release cloud from laser shock-loaded graphite and hydrocarbon targets: in search of diamonds

This work presents first insights into the dynamics of free-surface release clouds from dynamically compressed polystyrene and pyrolytic graphite at pressures up to 200 GPa, where they transform into diamond or lonsdaleite, respectively. These ejecta clouds are released into either vacuum or various types of catcher systems, and are monitored with high-speed recordings (frame rates up to 10 MHz). Molecular dynamics simulations are used to give insights to the rate of diamond preservation throughout the free expansion and the catcher impact process, highlighting the challenges of diamond retrieval. Raman spectroscopy data show graphitic signatures on a catcher plate confirming that the shock-compressed PS is transformed. First electron microscopy analyses of solid catcher plates yield an outstanding number of different spherical-like objects in the size range between ten(s) up to hundreds of nanometres, which are one type of two potential diamond candidates identified. The origin of some objects can unambiguously be assigned, while the history of others remains speculative

Recovery of release cloud from laser shock-loaded graphite and hydrocarbon targets: in search of diamonds

This work presents first insights into the dynamics of free-surface release clouds from dynamically compressed polystyrene and pyrolytic graphite at pressures up to 200 GPa, where they transform into diamond or lonsdaleite, respectively. These ejecta clouds are released into either vacuum or various types of catcher systems, and are monitored with high-speed recordings (frame rates up to 10 MHz). Molecular dynamics simulations are used to give insights to the rate of diamond preservation throughout the free expansion and the catcher impact process, highlighting the challenges of diamond retrieval. Raman spectroscopy data show graphitic signatures on a catcher plate confirming that the shock-compressed PS is transformed. First electron microscopy analyses of solid catcher plates yield an outstanding number of different spherical-like objects in the size range between ten(s) up to hundreds of nanometres, which are one type of two potential diamond candidates identified. The origin of some objects can unambiguously be assigned, while the history of others remains speculative

Design of a Flying V Subsonic Transport

Ten years after the initial sketches of the Flying V were made, we intend to give an overview of the development of this concept until the present day. The Flying V is a new concept for an efficient aircraft. It is a pure flying wing which includes a V-shaped passenger cabin. In this work, we describe how the concept developed - from the first drawings, the reasoning behind the concept and the design of the planform geometry, to the introduction of a structural solution for the pressurized cabin, to the design of a family of aircraft, detailed investigations of handling qualities and the interior layout. As of today, the concept promises a 20% lower fuel burn than a conventional reference aircraft on the same mission with the same capacity and the same wingspan, assuming current manufacturing techniques and current engine technology. Research activities on the Flying V have been continuously increasing over the past decade. Projects are ongoing in fields such as aerodynamics, structures and manufacturing, flight dynamics and control, the environmental impact of the design, aircraft integration, noise, and airport operation

Design of a Flying V Subsonic Transport

Ten years after the initial sketches of the Flying V were made, we intend to give an overview of the development of this concept until the present day. The Flying V is a new concept for an efficient aircraft. It is a pure flying wing which includes a V-shaped passenger cabin. In this work, we describe how the concept developed - from the first drawings, the reasoning behind the concept and the design of the planform geometry, to the introduction of a structural solution for the pressurized cabin, to the design of a family of aircraft, detailed investigations of handling qualities and the interior layout. As of today, the concept promises a 20% lower fuel burn than a conventional reference aircraft on the same mission with the same capacity and the same wingspan, assuming current manufacturing techniques and current engine technology. Research activities on the Flying V have been continuously increasing over the past decade. Projects are ongoing in fields such as aerodynamics, structures and manufacturing, flight dynamics and control, the environmental impact of the design, aircraft integration, noise, and airport operation.Flight Performance and Propulsio

Aerodynamic Design of a Flying V Aircraft in Transonic Conditions

The Flying V is a long-range, flying-wing aircraft where payload and fuel both reside in a V-shaped, crescent wing with large winglets that double as vertical tail planes. The objective of this study is to maximize the lift-to-drag (L/D) ratio of the Flying V in cruise conditions, i.e. CL= 0.26, M = 0.85 and to investigate its off-design performance in high-subsonic conditions. This is done by manually modifying the design parameters that describe the outer mold line of the Flying V and assessing the aerodynamic performance by means of computational fluid dynamics. A 15-million cell, third-order MUSCL, Reynolds-Averaged Navier Stokes solver with the Menter SST turbulence model is used to estimate the aerodynamic coefficients. This numerical model is validated using the experimental data of the ONERA M6 wing. A new, CATIA-based, parametrization of the Flying V is the starting point of the design. Three manual design phases improve the aerodynamic performance while satisfying all constraints. Design modifications include an increase in camber and aft-loading of the wing around 40% of the semispan and improved airfoil sections on the outboard wing generating the required lift coefficient towards an elliptical lift distribution. The twist distribution at the wing-winglet junction is optimized to reduce wave drag. This has resulted in an improvement of L/D from 20.3 from previous studies to 24.2 for the final version, while reducing the cruise angle of attack from 5.2 to 3.6 degrees. The drag divergence Mach number is estimated at 0.925.AerodynamicsGroup De BreukerFlight Performance and Propulsio

"Rostocker künstliches Herz"--gegenwärtiger Stand und Ausblick.

The authors report on their experiences gained by animal experiments (calf) and their attempts (human corpses) concerning adaptation of the apparatus to the human thorax. At the present time they do not see a chance for its routine clinical use. The main reason why is the impossibility to install the extrathoracic driving system into the thoracic cage and last not least the wear of the material used for the heart chambers

Zur Kanülenproblematik bei der Applikation von ventrikulären Herz-Kreislauf-Assistsystemen.

The prerequisite for efficient assist-ventricles and impulses in the pulsatile pumping function are sufficiently dimensioned afflux and flowing off connections. In systematic investigations on the hydraulic circulation model the cannulas from an internal parameter of 12 mm with a total length of the connection distance to the inflow and outflow valve, respectively, at the bypass ventricle of 30 cm proved sufficient for performing a volume of output of 5-6 l/min in clinic-relevant filling pressures in a hypodynamic circulatory situation. Connection cannulas for the heart-lung machine used in routine work are not sufficient in periodic filling and ejection processes in the pulsatile pumping function for an effective decompression and effective increase of the cardiac output. In case of an ECG-triggered mode of action of the ventricular assist-system an increase of frequency up to 130/min in after that incomplete filling of the assist-ventricle does not remarkably restrict the effectiveness of the assist-system

Erfahrungen mit dem Rostocker künstlichen Herz.

A totally artificial heart--the Rostock totally artificial heart (Rostock TAH) was implanted in calves. We can give the following deductions after 27 examinations: -- The Rostock TAH was tested successfully in endurance test about 7 months; it show no sign of wear. -- The surgical technique of the implantation was standardised and a successful experimentation is possible. -- The longest survival time was 15 days. The hemodynamic early results were very good in 3 other animals. -- Modifications of the Rostock TAH were taken up relating to the dimensions of the artificial ventriculi and by mounting a screw cap for avoiding an air embolism. -- Adaption tests in the corpse show that the present form of the artificial heart is not ideal for a possible application in man. -- The problem is still existing in developing a suitable drive system locates intrathoracically. The present drive and control system on a pneumatic base is qualified only for the animal experiment but not for a possible application in man