Fretting Corrosion Behavior of Additive Manufactured and Cryogenic-Machined Ti6Al4V for Biomedical Applications

Metal ion release, caused by synergistic effect of wear and corrosion, is one of the major concerns related to the prostheses lifetime. In this work, samples of additive manufactured Ti6Al4V are machined under dry cutting and cryogenic cooling conditions and their performances in terms of corrosion and fretting corrosion response are investigated. A wet and temperature-controlled apparatus equipped with an electro-chemical cell is designed and set-up in order to evaluate the fretting corrosion effect acting at the interfaces. The obtained results show that the cryogenic machining improves the corrosion and fretting corrosion behavior of the investigated additive manufactured Ti6Al4V

Head-neck taper corrosion in hip arthroplasty

Modularity at the head-neck junction of the femoral component in THA became popular as a design feature with advantages of decreasing implant inventory and allowing adjustment of leg length, offset, and soft tissue balancing through different head options. The introduction of a new modular interface to femoral stems that were previously monoblock, or nonmodular, comes with the potential for corrosion at the taper junction through mechanically assisted crevice corrosion. The incidence of revision hip arthroplasty is on the rise and along with improved wear properties of polyethylene and ceramic, use of larger femoral head sizes is becoming increasingly popular. Taper corrosion appears to be related to all of its geometric parameters, material combinations, and femoral head size. This review article discusses the pathogenesis, risk factors, clinical assessment, and management of taper corrosion at the head-neck junction.S. Hussenbocus, D. Kosuge, L. B. Solomon, D. W. Howie, and R. H. Oskoue

Head-Neck Taper Corrosion in Hip Arthroplasty

Copyright © 2015 S. Hussenbocus et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Modularity at the head-neck junction of the femoral component in THA became popular as a design feature with advantages of decreasing implant inventory and allowing adjustment of leg length, offset, and soft tissue balancing through different head options. The introduction of a new modular interface to femoral stems that were previously monoblock, or nonmodular, comes with the potential for corrosion at the taper junction through mechanically assisted crevice corrosion. The incidence of revision hip arthroplasty is on the rise and along with improved wear properties of polyethylene and ceramic, use of larger femoral head sizes is becoming increasingly popular. Taper corrosion appears to be related to all of its geometric parameters, material combinations, and femoral head size. This review article discusses the pathogenesis, risk factors, clinical assessment, and management of taper corrosion at the head-neck junction

Tribology of Medical Devices

Importance of tribology in a number of medical devices and surgical instruments is reviewed, including artificial joints, artificial teeth, dental implants and orthodontic appliances, cardiovascular devices, contact lenses, artificial limbs and surgical instruments. The current focus and future developments of these medical devices are highlighted from a tribological point of view, together with the underlying mechanisms

Implementation and Evaluation of a School-Based Anti-Tobacco Program in Mauritius: A Pilot Study to Assess the Usefulness and Reliability of a Tobacco Use Prevention Education Instrument

Tobacco use among Mauritian adolescents has increased steadily since 2008. Currently, Mauritius has not implemented any school-based anti-tobacco program and there is no instrument to assess the effectiveness of existing anti-tobacco school policies. Since the first cigarette can rapidly lead to nicotine dependence, targeted interventions must be assessed before established patterns of smoking appear. This study evaluated a tobacco use prevention education instrument to determine the effectiveness of a school-based anti-tobacco program. 26 male students completed a survey before and after receiving anti-tobacco lessons. Smoking initiation age could not predict likelihood of tobacco addiction (r(12)=0.320, p=0.311). However, after receiving the anti-tobacco lessons, participants were less likely to believe that youth who smoke have more friends (p \u3c 0.001) and were more knowledgeable about tobacco’s dangers (t(25)=3.94, p=0.001). This indicated that, with a few changes, the instrument can be used to assess the implementation of a school-based anti-tobacco program in Mauritius

Statistical differences in speech acoustics of major depressed and non-depressed adolescents

Speech acoustic parameters have been reported to provide highly efficient diagnostic cues for depression. Current studies have been focused on characterizing the speech of adult patients but it is known that adult speech differs significantly from adolescent speech, and that the onset of depression is likely to occur during adolescence itself. This paper investigates and explains the differences in speech acoustic parameters characterizing the speech of depressed and non-depressed adolescents, namely F0 (fundamental frequency), jitter, shimmer, log energy, spectral centroid, spectral entropy and glottal pulse duration. Speech data was collected from adolescents aged 14 - 18 and included 68 (49 females and 19 males) diagnosed with major depression and 71 (44 females and 27 males) diagnosed as non-depressed. The speech recordings were made during three different types of family interactions: event-planning, problemsolving and family consensus. Statistical analysis revealed that the differences between depressed and non-depressed speech acoustics strongly depend on gender and topic of conversation. For male adolescents, the glottal pulse duration was found to be the most efficient parameter in discriminating between depressed and non-depressed speech for all three interactions. For female adolescents, the fundamental frequency F0 was the most determinant during the problem solving and family consensus interactions, whilst the glottal pulse duration was the most determinant during the event planning interaction

Spontaneous spinal epidural hematoma: a case report and literature review

Abstract not availableSaleem M. Hussenbocus, Martin J. Wilby, Chris Cain, and David Hal

Is internal fixation alone advantageous in selected B2 periprosthetic fractures?

BACKGROUND: Revision surgery is currently the recommended treatment for Vancouver B2 femoral periprosthetic fractures, but isolated open reduction and internal fixation (ORIF) might be an effective treatment for these fractures around cemented collarless polished tapered (CCPT) stems, as these stems can re-engage in the cement mantle, regaining stability following internal fixation. The aim of this study was to determine the operative risks, post-operative complications, and radiographic and functional outcomes in two cohorts of Vancouver B2 femoral fractures around CCPT stems treated either by ORIF alone or revision surgery. METHODS: The results of 12 patients with B2 periprosthetic fractures around a CCPT stems treated by ORIF alone (median follow-up 67 months) were compared with those of nine patients with a similar fracture treated by revision surgery (median follow-up 59 months). RESULTS: All fractures treated by ORIF alone healed and all stems restabilized and remained stable within their original cement mantle. These patients had significantly shorter overall operating room times (P = 0.002), surgical times (P = 0.002) and required fewer units of blood transfusion (P = 0.008) than patients in the revision cohort. In the ORIF cohort, one patient had two dislocations. In the revision cohort, one patient had delayed wound healing, a second patient had delayed wound healing and two dislocations, and a third patient had two dislocations. CONCLUSION: Although further studies with larger numbers are required, treatment of these fractures with ORIF alone may be a viable alternative to revision surgery as it reduces the operative risks involved.Lucian B. Solomon, Saleem M. Hussenbocus, Tania A. Carbone, Stuart A. Callary, and Donald W. Howi