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Two heat treatments were carried out at below (Ti6Al4V 800 ) and above (Ti6Al4V 1050 ) the beta-phase transformation temperature (T TRANSUS  = 980 °C), to study the effect of microstructural changes on osseointegration. The alloys were implanted in the femurs of hind legs of Wistar rats for 15, 30, and 60 days. Histology of the femur sections obtained for the first 15 days showed inflammatory tissue surrounding the implants and tissue contraction, which prevented osseointegration in early stages. After 30 days, trabecular bone, reduction of inflammatory tissue around the implants, and osseointegration were observed in Ti6Al4V as received and Ti6Al4V 1050 alloys, while osseointegration was detected for the three alloys after 60 days. These results were supported through morphometric studies based on the analysis of Bone Implant Contact (BIC), where there was a larger bone contact after 60 days for the Ti6Al4V 1050 alloy; indicating that microstructural features of the Ti6Al4V alloys influence their osseointegration, with the lamellar microstructure (Ti6Al4V 1050 ), being the most responsive. Graphical abstract., (© 2022. The Author(s).)

Electrochemically reduced graphene oxide (ErGO) films on a biomedical grade CoCr alloy have been generated and characterized in order to study their possible application for use on joint prostheses. The electrodeposition process was performed by cyclic voltammetry. The characterization of the ErGO films on CoCr alloys by XPS revealed sp2 bonding and the presence of CO and CO residual groups in the graphene network. Biocompatibility studies were performed with mouse macrophages J774A.1 cell cultures measured by the ratio between lactate dehydrogenase and mitochondrial activities. An enhancement in the biocompatibility of the CoCr with the ErGO films was obtained, a result that became more evident as exposure time increased. Macrophages on the CoCr with the ErGO were well-distributed and conserved the characteristic cell shape. In addition, vimentin expression was unaltered in comparison with the control, results that indicated an improvement in the CoCr biocompatibility with the ErGO on the material surface. The in vivo response of graphene and graphene oxide was assessed by intraperitoneal injection in wistar rats. Red blood cells are one of the primary interaction sites so hemocompatibility tests were carried out. Rats inoculated with graphene and graphene oxide showed red blood cells of smaller size with a high content in hemoglobin., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Porous tantalum trabecular-structured metal (PTTM) has been applied to titanium orthopedic and dental implants. This study evaluated the healing pattern of bone growth into experimental PTTM cylinders (N = 24; 3.0 × 5.0 mm) implanted in the partially edentulous jaws of 23 healthy volunteers divided into four groups. Six PTTM cylinders per group were explanted, prepared, and analyzed histologically/metrically after 2, 3, 6, and 12 weeks of submerged healing. PTTM implant osseoincorporation resulted from the formation of an osteogenic tissue network that over the course of 12 weeks resulted in vascular bone volume levels in PTTM that are comparable to clinically observed mean trabecular volumes in edentulous posterior jaws.

Background: Hip fractures in the elderly are a common reason for admission to the department of orthopaedic surgery, this condition asks an important part of health resources and is associated with high levels of co-morbidity and mortality. Many improvements have been introduced in the treatment of these patients, preoperative regional analgesia, intensive physical therapy, interdisciplinary care program; but still remain unresolved gaps. The aim of this study is to document the natural history of early versus delayed surgical intervention in elderly patients with hip fractures and to establish the prognostic factors of mortality and walking ability after discharge., Methods: A sample of 499 patients admitted in our Institution was prospectively reviewed between February 2008 and February 2013. Preoperatively characteristics and functional data were assessed in relation with time to surgery (focused on mortality and ability to walk at first year)., Results: The ability to walk and activities of daily living (functional results) were not associated with surgical delays (surgery before 24h from admission, surgery among 24h and 72h from admission and surgery later than 72h). However, ASA class, Parkinson disease and age were significantly associated with poor functional results. In the same way, mortality at 1year was not associated with time to surgery, but ASA class was associated with significant risk factor of 1 year-mortality., Conclusions: ASA class, Parkinson disease and age are independent predictor of poor functional outcomes after intracapsular hip fracture. In addition, ASA class is an independent predictor of mortality. Patients with poor functional status before fracture and older than 75 years would benefit from geriatric and rehabilitation intervention immediately after surgery., (Copyright © 2017 Elsevier Ltd. All rights reserved.)