Alister J Hart
Affiliation: Imperial College
- The painful metal-on-metal hip resurfacingA J Hart
Department of Radiology Imperial College, Charing Cross Hospital, London, UK
J Bone Joint Surg Br 91:738-44. 2009..These three clinically useful investigations can help to determine the cause of failure of the implant, predict the need for future revision and aid the choice of revision prostheses...
- The chemical form of metallic debris in tissues surrounding metal-on-metal hips with unexplained failureAlister J Hart
Department of Orthopaedic Surgery, Imperial College and Imperial College Healthcare NHS Trust, Charing Cross Hospital Campus, Fulham Palace Road, London W68RF, UK
Acta Biomater 6:4439-46. 2010..The variety of metallic species may have arisen from corrosion, wear or a combination of both. No evidence of Cr(VI) was seen in the tissues examined...
- Which factors determine the wear rate of large-diameter metal-on-metal hip replacements? Multivariate analysis of two hundred and seventy-six componentsA J Hart
Department of Musculoskeletal Surgery, Imperial College Charing Cross Hospital Campus, Fulham Palace Road, London, UK
J Bone Joint Surg Am 95:678-85. 2013..We sought to understand the variation in wear rates in a large series of retrieved metal-on-metal hip arthroplasty components...
- Understanding why metal-on-metal hip arthroplasties fail: a comparison between patients with well-functioning and revised birmingham hip resurfacing arthroplasties. AAOS exhibit selectionAlister J Hart
Department of Musculoskeletal Surgery, Imperial College London, Charing Cross Hospital Campus, Fulham Palace Road, London W6 8RF, United Kingdom
J Bone Joint Surg Am 94:e22. 2012....
- Pseudotumors in association with well-functioning metal-on-metal hip prostheses: a case-control study using three-dimensional computed tomography and magnetic resonance imagingAlister J Hart
Department of Orthopaedic Surgery, Charing Cross Hospital Imperial College Healthcare NHS Trust and Imperial College London, Fulham Palace Road, London W6 8RF, United Kingdom
J Bone Joint Surg Am 94:317-25. 2012....
- Insufficient acetabular version increases blood metal ion levels after metal-on-metal hip resurfacingAlister J Hart
Department of Orthopaedic Surgery, Imperial College, Charing Cross Hospital Campus, London SW7 2AZ, UK
Clin Orthop Relat Res 469:2590-7. 2011..Thus the relationship between version and blood metal ions levels has not been resolved...
- The relationship between the angle of version and rate of wear of retrieved metal-on-metal resurfacings: a prospective, CT-based studyA J Hart
Department of Musculoskeletal Surgery, Imperial College, London, United Kingdom
J Bone Joint Surg Br 93:315-20. 2011..We were unable to show that excess version of the acetabular component alone or combined with femoral version was associated with an increase in the rate of wear based on our assessment of version using CT...
- Large ball metal on metal hips obscure cup angle measurement on plain radiographsAlister J Hart
Department of Musculoskeletal Surgery, Imperial College London, Charing Cross Hospital Campus, London, UK
Hip Int 19:323-9. 2009..We have used a metal artefact reduction CT protocol with a 3D imaging software package to overcome this problem and measure cup position relative to the Anterior Pelvic Plane...
- Circulating levels of cobalt and chromium from metal-on-metal hip replacement are associated with CD8+ T-cell lymphopeniaA J Hart
Department of Musculoskeletal Surgery Charing Cross, Imperial College, London, England
J Bone Joint Surg Br 91:835-42. 2009....
- Cup inclination angle of greater than 50 degrees increases whole blood concentrations of cobalt and chromium ions after metal-on-metal hip resurfacingA J Hart
Department of Musculoskeletal Surgery, Imperial College Healthcare NHS Trust, Charing Cross Hospital, London, UK
Hip Int 18:212-9. 2008..The implication is that metal levels can be minimised with optimal orientation of the acetabular component...
- Sensitivity and specificity of blood cobalt and chromium metal ions for predicting failure of metal-on-metal hip replacementA J Hart
Imperial College London, Department of Musculoskeletal Surgery, Charing Cross Hospital Campus, Fulham Palace Road, London W6 8RF, UK
J Bone Joint Surg Br 93:1308-13. 2011..Blood metal ions had good discriminant ability to separate failed from well-functioning hip replacements. The MHRA cut-off level of 7 ppb provides a specific test but has poor sensitivity...
- Revision of metal-on-metal hip arthroplasty in a tertiary center: a prospective study of 39 hips with between 1 and 4 years of follow-upAlexander D Liddle
Department of Orthopaedic Surgery, Imperial College, Charing Cross Hospital, London, UK
Acta Orthop 84:237-45. 2013..As a result, planning of theater time and resources is difficult, surgery is challenging, and outcomes are often poor. We describe our experience with revision of MOMHA and provide recommendations for management...
- Pseudotumors are common in well-positioned low-wearing metal-on-metal hipsAshley K Matthies
Department of Musculoskeletal Surgery, Imperial College London, London, SW7 2AZ, UK
Clin Orthop Relat Res 470:1895-906. 2012..However, the pathogenesis of these lesions remains unclear. Currently, there is inconsistent evidence regarding the influence of adverse cup position and increased wear in the formation of pseudotumors...
- Magnetic resonance imaging findings in painful metal-on-metal hips: a prospective studyShiraz A Sabah
Imperial College London, London, UK
J Arthroplasty 26:71-6, 76.e1-2. 2011..Metal artifact reduction sequence magnetic resonance imaging may be useful to diagnose and monitor at-risk hips but requires validation in well-functioning MOM hips before it can guide clinical decision making...
- Cobalt from metal-on-metal hip replacements may be the clinically relevant active agent responsible for periprosthetic tissue reactionsAlister J Hart
Department of Orthopaedic Surgery, Imperial College and Imperial College Healthcare NHS Trust, Charing Cross Hospital Campus, London, UK
Acta Biomater 8:3865-73. 2012..There is in vitro evidence that Co is more important than Cr in the inflammatory process, but there are no reported human tissue studies of the analysis of implant-derived metals...
- A retrieval analysis of explanted Durom metal-on-metal hip arthroplastiesAshley K Matthies
Department of Musculoskeletal Surgery, Imperial College London, London, UK
Hip Int 21:724-31. 2011..This supports recent clinical findings of high revision rates as a result of acetabular loosening for the Durom metal-on-metal hip system...
- Chemical speciation of nanoparticles surrounding metal-on-metal hipsAngela E Goode
Department of Materials, Imperial College London, London, UK
Chem Commun (Camb) 48:8335-7. 2012..The majority of debris contained Cr(3+), with trace amounts of oxidised cobalt. A minority phase containing a core of metallic chromium and cobalt was also observed...
- Native acetabular version: 3D CT analysis
of the psoas valleyHumza Tariq Osmani
Trauma and Orthopaedics Department, Imperial College Charing Cross Hospital, London W6 8RF, UK
Hip Int 23:274-80. 2013..This adds to our understanding of native bony anatomy, and specifically provides a landmark that 3D CT has demonstrated to be potentially useful in assessing native version...
- Variation in taper surface roughness for a single design effects the wear rate in total hip arthroplastyRobert K Whittaker
Institute of Orthopaedics and Musculoskeletal Science, University College London and the Royal National Orthopaedic Hospital, Brockley Hill, Stanmore, London, HA7 4LP, United Kingdom
J Orthop Res . 2016..The variability of "as manufactured" surface roughness has a significant effect on taper material loss. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res...
- Learning how to resurface cam-type femoral heads with acceptable accuracy and precision: the role of computed tomography-based navigationJustin P Cobb
Department of Orthopaedics, Imperial College London, 5 Devonshire Place, London W1G 6HL, United Kingdom
J Bone Joint Surg Am 90:57-64. 2008..Three models of cam-type hips of increasing severity were used to assess the efficacy of three systems of instrumentation at delivering the required level of accuracy and precision...
- Retrieval analysis of 240 metal-on-metal hip components, comparing modular total hip replacement with hip resurfacingA Matthies
Department of Musculoskeletal Surgery, Imperial College London, London, United Kingdom
J Bone Joint Surg Br 93:307-14. 2011..These findings show that failed metal-on-metal hip resurfacing and modular THRs have similar component wear rates and are both associated with raised pre-revision blood levels of metal ions...
- Detection of metallic cobalt and chromium liver deposition following failed hip replacement using T2* and R2 magnetic resonanceAmna Abdel-Gadir
Institute of Cardiovascular Science, University College London, London, UK
J Cardiovasc Magn Reson 18:29. 2016..Cobalt and chromium, like iron, also affect magnetism and are proposed MR contrast agents...
- Simple isolation method for the bulk isolation of wear particles from metal on metal bearing surfaces generated in a hip simulator testFang Lu
School of Engineering and Material Science, Queen Mary University of London, London, UK
J Mater Sci Mater Med 23:891-901. 2012..The present study involved a total of eight steps for the isolation process and a wear particle extraction efficiency of 45% was achieved...
- Clinical Cold Welding of the Modular Total Hip Arthroplasty ProsthesisRobert K Whittaker
Institute of Orthopaedics and Musculoskeletal Science, University College London and the Royal National Orthopaedic Hospital, London, United Kingdom
J Arthroplasty . 2016..A head that is "clinically cold welded" to a stem is one of the commonest reasons for unplanned removal of the stem. It is not clear which hip designs are at greatest risk of clinical cold welding...
- 2D measurements of cup orientation are less reliable than 3D measurementsKinner Davda
Imperial College, Charing Cross Hospital, London, UK
Acta Orthop 86:485-90. 2015..The secondary aim was to quantify the agreement for cup inclination. Lastly, we wanted to determine the inter- and intra-observer reliability of both methods...
- The palmar locking compression plate is biomechanically comparable to the dorsal pi plate for dorsally comminuted, intraarticular wrist fracturesA J Hart
Department of Trauma and Orthopaedic Surgery, Charing Cross Hospital, London, UK
J Hand Surg Eur Vol 32:388-93. 2007..036). However, the absolute difference was only 0.5 mm. Such a small difference is unlikely to be clinically detectable and, therefore, we conclude that there is no clinically significant difference between the two types of fixation...