214 research outputs found
The Improved Standards for Laboratory Animals Act and the Proposed Regulations: A Glimmer of Home In the Battle Against Abusive Animal Research
Simultaneous chronic rupture of quadriceps tendon and contra-lateral patellar tendon in a patient affected by tertiary hyperparatiroidism
Spontaneous ruptures of the extensor mechanism of the knee are very rare. They tend to increase considerably in patients with metabolic diseases such as chronic renal failure, hyperparathyroidism, diabetes, gout, and systemic lupus erythematosus. The reported case regards a 48-year-old man with chronic, spontaneous and simultaneous quadriceps, and contra-lateral patellar tendon rupture. The patient suffered from chronic renal failure and for the past year from tertiary hyperparathyroidism. Ruptured tendons were repaired and both knee were evaluated monthly for the next 12Â months. Good functional recovery was achieved on both knees without relapse. This case emphasizes the importance of long-term high parathyroid hormone level in the etiology of tendons ruptures
Bilateral simultaneous rupture of the quadriceps tendon in a patient with psoriasis: a case report and review of the literature
<p>Abstract</p> <p>Introduction</p> <p>Bilateral quadriceps tendon rupture is not common in the absence of systemic disease. Patients with chronic systemic diseases such as uremia and systemic lupus erythematosus and patients who are being treated with systemic steroids or local steroid injections are more prone to tendon rupture. The tendon can rupture spontaneously or as a result of trauma. We report an unusual case of simultaneous bilateral traumatic quadriceps tendon rupture in a patient with psoriasis who was being treated with topical steroid preparations.</p> <p>Case presentation</p> <p>A 57-year-old Caucasian man with a known history of psoriasis, for which he was being treated with topical steroid preparations, presented to our hospital with clinical signs of bilateral quadriceps tendon rupture after he fell while walking down stairs. The diagnosis was confirmed by bilateral ultrasound scans of the thighs. The patient underwent surgery to repair both quadriceps tendons. Post-operatively, the patient was immobilized first in bilateral cylinder casts for six weeks, then in knee braces for the next four weeks. His knees were actively mobilized during physiotherapy.</p> <p>Conclusion</p> <p>Bilateral quadriceps tendon rupture is a rare occurrence in patients with psoriasis who are being treated with topical steroids.</p
Enhanced hydrothermal resistance of Y-TZP ceramics through colloidal processing
Two commercial zirconia powders with 3mol% of yttria (TZ3YE and TZ3YS, labeled as ZE and ZS, respectively) supplied by Tosoh (Japan) were used for this study. Maximum colloidal stability for ZE was achieved by dispersing the powders in a mixture of water/ethanol of 90:10 (wt/wt) using a sonication probe. The rheological behavior of the suspensions was optimized in terms of solids content ranging from 20 to 33vol% and sonication time (06min), the best results being obtained after 2min. ZS samples were prepared to a solids loading of 30vol% in water dispersing with 2min-sonication. Samples obtained by slip casting in plaster molds were used for dynamic sintering studies, and fully dense and nanostructured specimens were obtained at temperatures of 1300 degrees C1350 degrees C (ZE samples) and 1400 degrees C per 2h (ZS samples). The Hardness (H) and Young's Modulus (E) properties of the specimens were studied by nanoindentation technique giving 17 and 250GPa mean values for H and E, respectively. The specimens were then forced to a low-temperature degradation (LTD) treatment at 130 degrees C for 240h in steps of 60h. Raman spectroscopy and nanoindentation results of hydrothermally treated samples showed the absence of transformation from tetragonal to monoclinic phase until 180h whereas the mechanical properties maintained constant even at the sample surface. After 240h of LTD, the monoclinic phase was detected on all specimens by Raman peaks centered at 180, 191, and 383cm1. The nanoindentation study revealed an important loss of mechanical features reaching 10 and 175GPa for H and E, respectively. In the case of the ZS specimens, no monoclinic phase is detected after 240h of LTD treatment and no decay of E or H is detected. The free defect microstructure reached for the ZS specimen revealed a higher hydrothermal resistance so that it is concluded that the excellent behavior against thermal degradation is possible due to the large uniformity obtained by colloidal processing rather than the particle size of the starting powders.This work has been supported by Spanish Ministry of Science and Innovation (Projects MAT2009-14144-C03-02, MAT2009-14369-C02-01, and MAT2008-03398). Authors thank Prof. M. Anglada for helpful comments and discussion. R Moreno thanks the Universidad Politecnica de Valencia for the concession of a grant in the frame of its Program of Support to R+D (PAID-02-11, R-1752). We also wish to acknowledge Rut Benavente for her excellent technical support.RayĂłn Encinas, E.; Moreno, R.; Alcazar, C.; Salvador Moya, MD.; ManjĂłn Herrera, FJ.; Jimenez-Pique, E.; Llanes, L. (2013). Enhanced hydrothermal resistance of Y-TZP ceramics through colloidal processing. 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Wear and degradation on retrieved zirconia femoral heads
Zirconia femoral heads retrieved from patients after different implantation periods (up to 13 years) were analysed using vertical scanning interferometry, atomic force microscopy and Raman microspectroscopy. A range of topographical and compositional changes on the surface of the retrievals are reported in this work. The study revealed that changes in roughness are the result of a combination of factors, i.e. scratching, surface upheaval due to transformation to the monoclinic phase and grain pull-out. Clusters of transformed monoclinic grains were observed on heads implanted for more than 3 years. The phase composition of these clusters was confirmed by Raman microspectroscopy. Increased abrasive wear and a higher monoclinic phase content concentrated on the pole of the femoral heads, confirming that the tetragonal to monoclinic phase transformation was not only induced by the tetragonal phase metastability and environmental conditions but mechanical and tribological factors, also affected the transformation kinetics. Additionally, the head implanted for 13 years showed evidence of a self-polishing mechanism leading to a considerable smoothening of the surface. These observations provide an insight into the interrelated mechanisms underlying the wear and transformation process on zirconia ceramics during implantation
In vivo wear performance of highly cross-linked polyethylene vs. yttria stabilized zirconia and alumina stabilized zirconia at a mean seven-year follow-up
Dutch guideline on total hip prosthesis
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The Role of Anabolic Androgenic Steroids in Disruption of the Physiological Function in Discrete Areas of the Central Nervous System
Subtrochanteric shortening osteotomy combined with cemented total hip arthroplasty for Crowe group IV hips
Comparison of transverse and modified subtrochanteric femoral shortening osteotomy in total hip arthroplasty for developmental dysplasia of hip: a meta-analysis
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