We performed 204 cementless total hip arthroplasties using a fully porous stem made of a cast cobalt-chrome-molybdenum alloy. Five stems fractured at the middle part. Champagne-fluted canals (P<.0001) and low canal fillings 1 cm below the lesser trochanter (P =.02) significantly correlated with stem fractures. Subsequent surgery revealed that all of the proximal parts were surrounded by fibrous tissue, and the distal parts showed bone ingrowth. Numerous voids were present close to the surface of the implant body. The core diameters of the fractured stems were 4 to 5 mm. The fractures may be attributed to the combination of the lack of proximal support, a champagne-fluted canal, the fully porous stem made of a cast cobalt-chrome-molybdenum alloy, and the narrow dimension of the stem core.
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http://dx.doi.org/10.1054/arth.2002.35822 | DOI Listing |
PLoS One
January 2025
School of Petrochemical Engineering, Changzhou University, Changzhou, China.
The influence of varying hydrogen content on the microstructure, mechanical properties, and fracture behavior of the metastable β titanium alloy TB8 after hydrogen charging has been investigated in this study. Several characterization methods, including optical microscopy (OM), x-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), were employed to comprehensively analyze the alloy. The results show that with the addition of hydrogen, hydrogen mainly accumulated at grain boundaries in the form of hydrides.
View Article and Find Full Text PDFSci Rep
January 2025
Agronomy Collage Jilin Agricultural University, Changchun, 130118, China.
Rice yield could be increased by apply higher level of nitrogen fertilizer, but excessive use of nitrogen fertilizer will cause plant lodging. This study aimed to investigate the effect of nitrogen application rate on lodging resistance of rice stems. Four japonica rice varieties with different lodging resistance were used, and six nitrogen fertilizer levels were set up to analyze the morphological structure, mechanical properties, and chemical components of rice stems under such treatments.
View Article and Find Full Text PDFJ Am Acad Orthop Surg
January 2025
From the Hawaii Permanente Medical Group, Kaiser Permanente, Honolulu, HI (Okike), the Department of Surgical Outcomes and Analysis, Kaiser Permanente, San Diego, CA (Prentice, Paxton, and Fasig), the San Francisco Orthopaedic Residency Program, San Francisco, CA (Shah), the Permanente Medical Group, Oakland, CA (Grimsrud), and the Washington Permanente Medical Group P.C, Seattle, WA (Chen).
Background: Cemented fixation is recommended in the hemiarthroplasty treatment of geriatric femoral neck fractures. Certain cemented stems have similarly designed "low-demand" counterparts, but it is unclear whether they yield comparable clinical outcomes. The purpose of this study was to evaluate the revision risk associated with two low-demand stems, Summit Basic (DePuy Synthes) and Versys LD/Fx (Zimmer Biomet), in comparison to their standard counterparts, Summit (DePuy Synthes) and Versys Advocate (Zimmer Biomet).
View Article and Find Full Text PDFRegulatory T cells (Tregs) are increasingly being recognized for their role in promoting tissue repair. In this issue of the JCI, Chen et al. found that Tregs at the site of bone injury contribute to bone repair.
View Article and Find Full Text PDFElife
January 2025
Center for Medical Genetics Ghent, Department of Biomolecular Medicine, Ghent University, Ghent, Belgium.
Heritable fragile bone disorders (FBDs), ranging from multifactorial to rare monogenic conditions, are characterized by an elevated fracture risk. Validating causative genes and understanding their mechanisms remain challenging. We assessed a semi-high throughput zebrafish screening platform for rapid in vivo functional testing of candidate FBD genes.
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