Alexej Barg

Bio: Alexej Barg is an academic researcher from University of Utah. The author has contributed to research in topics: Ankle & Ankle replacement. The author has an hindex of 39, co-authored 259 publications receiving 5234 citations. Previous affiliations of Alexej Barg include Rashid Hospital & University Hospital of Basel.

Realignment surgery as alternative treatment of varus and valgus ankle osteoarthritis.

Abstract: In patients with asymmetric (varus or valgus) ankle osteoarthritis, realignment surgery is an alternative treatment to fusion or total ankle replacement in selected cases. To determine whether realignment surgery in asymmetric ankle osteoarthritis relieved pain and improved function, we clinically and radiographically followed 35 consecutive patients with posttraumatic ankle osteoarthritis treated with lower leg and hindfoot realignment surgery. We further questioned if outcome correlated with achieved alignment. The average patient age was 43 years (range, 26-68 years). We used a standardized clinical and radiographic protocol. Besides distal tibial osteotomies, additional bony and soft tissue procedures were performed in 32 patients (91%). At mean followup of 5 years (range, 3-10.5 years), pain decreased by an average of 4 points on a visual analog scale; range of ankle motion increased by an average of 5 degrees . Walking ability and the functional parts of the American Foot and Ankle Society score increased by an average of 10 and 21 points, respectively, and correlated with achieved reversal of tibiotalar tilt and the score of Takakura et al. Revision surgery was performed in 10 ankles (29%), of which three ankles (9%) were converted to total ankle replacement. We believe the data support realignment surgery for patients with asymmetric ankle osteoarthritis.

Weightbearing Computed Tomography of the Foot and Ankle: Emerging Technology Topical Review.

Abstract: In the last decade, cone-beam computed tomography technology with improved designs allowing flexible gantry movements has allowed both supine and standing weight-bearing imaging of the lower extremity. There is an increasing amount of literature describing the use of weightbearing computed tomography in patients with foot and ankle disorders. To date, there is no review article summarizing this imaging modality in the foot and ankle. Therefore, we performed a systematic literature review of relevant clinical studies targeting the use of weightbearing computed tomography in diagnosis of patients with foot and ankle disorders. Furthermore, this review aims to offer insight to those with interest in considering possible future research opportunities with use of this technology.Level of Evidence: Level V, expert opinion.

The Scandinavian total ankle replacement: long-term, eleven to fifteen-year, survivorship analysis of the prosthesis in seventy-two consecutive patients.

Abstract: The prosthesis discussed in this study was never made available in the U.S., and the manufacturer discontinued the use of this particular implant in favor of the titanium-spray design. This is discussed in an exchange between two of the authors and a reader in letters published as a data supplement attached to this article. Background: The objective of this study was to determine the long-term survivorship and clinical and radiographic results of the Scandinavian Total Ankle Replacement (STAR). Methods: From February 1996 to March 2000, seventy-seven ankles in seventy-two patients (thirty-seven female and thirty-five male patients, with an average age of fifty-six years) underwent total ankle replacement using the STAR prosthesis with a single coating of hydroxyapatite. Two patients were lost to follow-up, and twelve patients with thirteen ankle replacements died. The average duration of follow-up for the patients without revision was 12.4 years (range, 10.8 to 14.9 years). Sixty-two of the seventy-seven ankles were available for final follow-up. Results: Twenty-nine (38%) of the seventy-seven ankles had a revision of at least one of the metallic components. The probability of implant survival was 70.7% at ten years and 45.6% at fourteen years. The main reasons for revision were aseptic loosening, subsidence of the talar component, and progressive cyst formation. Polyethylene insert fractures were observed in eleven ankles. Conclusions: While the midterm to short-term results for patients managed with the STAR prosthesis have been encouraging at 3.7 years, the long-term survivorship of the same cohort was considerably inferior. The subjective and clinical results of the patients with retained prostheses are generally good and comparable with results reported in the current literature. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

HINTEGRA total ankle replacement: survivorship analysis in 684 patients.

Abstract: Background: Total ankle replacement is increasingly recommended for patients with end-stage ankle osteoarthritis. We analyzed the survivorship of 722 arthroplasties performed with one type of three-component total ankle prosthesis. Methods: Seven hundred and seventy-nine primary total ankle arthroplasties (741 patients) were performed between May 2000 and July 2010 with use of the HINTEGRA three-component prosthesis. A logistic multiple regression model was used to identify independent risk factors for prosthesis failure in 684 patients (722 ankles). The mean time to final follow-up (and standard deviation) was 6.3 ± 2.9 years. Results: Seven hundred and twenty-two ankles (684 patients) were available for survivorship analysis at the latest follow-up. The overall survival rates were 94% and 84% after five and ten years, respectively. Sixty-one ankles had a revision arthroplasty (twenty-seven both components, thirteen the tibial component only, and fourteen the talar component only) or were converted to a fusion (seven ankles).There were no polyethylene failures. There were no amputations. The generation category of the prosthesis, the cause of ankle osteoarthritis, and the age of the patient were identified as independent risk factors for prosthesis failure. Conclusions: The midterm survivorship of the HINTEGRA implant was comparable with that of other third-generation total ankle replacements. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Sarcoidosis

Abstract: 结节病易误诊,据王洪武等~([1])收集国内18篇关于此病误诊的文献,误诊率高达63.2%,当然有误诊就会有误治,如孙永昌等~([2])报道26例结节病在影像学检查诊断的第一印象中拟诊结核5例,其中就有2例完成规范的抗结核治疗,为此应引起临床对本病诊治的重视。

Guidelines for the management of hemophilia.

Abstract: Hemophilia is a rare disorder that is complex to diagnose and to manage. These evidence-based guidelines offer practical recommendations on the diagnosis and general management of hemophilia, as well as the management of complications including musculoskeletal issues, inhibitors, and transfusion-transmitted infections. By compiling these guidelines, the World Federation of Hemophilia aims to assist healthcare providers seeking to initiate and/or maintain hemophilia care programs, encourage practice harmonization around the world and, where recommendations lack adequate evidence, stimulate appropriate studies.

Shear-induced unfolding triggers adhesion of von Willebrand factor fibers.

Abstract: von Willebrand factor (VWF), a protein present in our circulatory system, is necessary to stop bleeding under high shear-stress conditions as found in small blood vessels. The results presented here help unravel how an increase in hydrodynamic shear stress activates VWF's adhesion potential, leading to the counterintuitive phenomena of enhanced adsorption rate under strong shear conditions. Using a microfluidic device, we were able to mimic a wide range of bloodflow conditions and directly visualize the conformational dynamics of this protein under shear flow. In particular, we find that VWF displays a reversible globule-stretch transition at a critical shear rate gamma(crit) in the absence of any adsorbing surface. Computer simulations reproduce this sharp transition and identify the large size of VWF's repeating units as one of the keys for this unique hydrodynamic activation. In the presence of an adsorbing collagen substrate, we find a large increase in the protein adsorption at the same critical shear rate, suggesting that the globule unfolding in bulk triggers the surface adsorption in the case of a collagen substrate, which provides a sufficient density of binding sites. Monitoring the adsorption process of multiple VWF fibers, we were able to follow the formation of an immobilized network that constitutes a "sticky" grid necessary for blood platelet adhesion under high shear flow. Because areas of high shear stress coincide with a higher chance for vessel wall damage by mechanical forces, we identified the shear-induced increase in the binding probability of VWF as an effective self-regulating repair mechanism of our microvascular system.

Management of severe perioperative bleeding: guidelines from the European Society of Anaesthesiology: First update 2016.

Abstract: The management of perioperative bleeding involves multiple assessments and strategies to ensure appropriate patient care. Initially, it is important to identify those patients with an increased risk of perioperative bleeding. Next, strategies should be employed to correct preoperative anaemia and to

Arterial thrombosis—insidious, unpredictable and deadly

Abstract: The formation of blood clots--thrombosis--at sites of atherosclerotic plaque rupture is a major clinical problem despite ongoing improvements in antithrombotic therapy. Progress in identifying the pathogenic mechanisms regulating arterial thrombosis has led to the development of newer therapeutics, and there is general anticipation that these treatments will have greater efficacy and improved safety. However, major advances in this field require the identification of specific risk factors for arterial thrombosis in affected individuals and a rethink of the 'one size fits all' approach to antithrombotic therapy.