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Stanga PE, Tsamis E, Siso-Fuertes I, Dorn JD, Merlini F, Fisher A, Crawford FI, Kasbia SS, Papayannis A, Baseler HA, Morland AB, Hanson RL, Humayun M, Greenberg RJ. Electronic retinal prosthesis for severe loss of vision in geographic atrophy in age-related macular degeneration: First-in-human use. Eur J Ophthalmol 2021; 31:920-931. [PMID: 33736500 DOI: 10.1177/11206721211000680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND To date there are yet no available approved therapies for Geographic Atrophy (GA) secondary to age-related macular degeneration (AMD). METHODS Single site, non-randomized safety and efficacy study presenting the preliminary results in a cohort of five late stage AMD (GA) patients successfully implanted with the Argus II Retinal Prosthesis System (Second Sight Medical Products Inc., Sylmar, CA, USA). Extensive fundus imaging including retinal photographs from which the GA area was measured. A combination of custom and traditional tests designed for very low vision subjects assessed visual function in study subjects. A Functional Low-Vision Observer Rated Assessment was carried out to evaluate the impact of the system on the subject's daily life. In addition, a study to evaluate structural characteristics of the visual cortex of the brain was performed in one subject using magnetic resonance imaging. RESULTS Seven device-related adverse events were reported, four of which were classed as serious adverse events. Retinal detachment was reported in three patients and was successfully treated within 12 months of onset. Testing showed an improvement in visual function in three of five patients with the system turned on. Magnetic resonance imaging assessed in one patient after implantation indicates a selective increase in cortical myelin and thickness in visual brain regions 1 year post implantation. CONCLUSIONS Epiretinal prostheses can successfully be implanted in those affected by GA secondary to late-stage AMD and can elicit visual percepts by electrical stimulation of residual neuroretinal elements and improve basic visual function in those affected.
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Affiliation(s)
- Paulo E Stanga
- Manchester Vision Regeneration (MVR) Lab at Manchester Royal Eye Hospital, NIHR Manchester Clinical Research Facility and Manchester University NHS Foundation Trust, Manchester, UK.,Division Evolution & Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, UK.,Retina Service, London Vision Clinic, London, UK
| | - Emmanouil Tsamis
- Manchester Vision Regeneration (MVR) Lab at Manchester Royal Eye Hospital, NIHR Manchester Clinical Research Facility and Manchester University NHS Foundation Trust, Manchester, UK.,Division Pharmacy & Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, UK
| | - Irene Siso-Fuertes
- Manchester Vision Regeneration (MVR) Lab at Manchester Royal Eye Hospital, NIHR Manchester Clinical Research Facility and Manchester University NHS Foundation Trust, Manchester, UK
| | - Jessy D Dorn
- Second Sight Medical Products, Inc, Sylmar, CA, USA
| | | | | | - Fiona Ij Crawford
- Manchester Vision Regeneration (MVR) Lab at Manchester Royal Eye Hospital, NIHR Manchester Clinical Research Facility and Manchester University NHS Foundation Trust, Manchester, UK
| | - Shakti S Kasbia
- Manchester Vision Regeneration (MVR) Lab at Manchester Royal Eye Hospital, NIHR Manchester Clinical Research Facility and Manchester University NHS Foundation Trust, Manchester, UK
| | - Alessandro Papayannis
- Manchester Vision Regeneration (MVR) Lab at Manchester Royal Eye Hospital, NIHR Manchester Clinical Research Facility and Manchester University NHS Foundation Trust, Manchester, UK.,SC di Oculistica Ospedali di Monfalcone e Gorizia, Azienda Sanitaria Universitaria Giuliano Isontina, Monfalcone, Italy
| | - Heidi A Baseler
- Hull York Medical School, Hull, Kingston upon Hull, UK.,Department of Psychology, University of York, UK.,York Neuroimaging Centre, University of York, UK
| | - Antony B Morland
- Department of Psychology, University of York, UK.,York Neuroimaging Centre, University of York, UK
| | - Rachel L Hanson
- Department of Psychology, University of York, UK.,York Neuroimaging Centre, University of York, UK
| | - Mark Humayun
- Ophthalmology and Biomedical Engineering, USC Roski Eye Institute, Los Angeles, CA, USA
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Rizzo S, Barale PO, Ayello-Scheer S, Devenyi RG, Delyfer MN, Korobelnik JF, Rachitskaya A, Yuan A, Jayasundera KT, Zacks DN, Handa JT, Montezuma SR, Koozekanani D, Stanga PE, da Cruz L, Walter P, Augustin AJ, Chizzolini M, Olmos de Koo LC, Ho AC, Kirchhof B, Hahn P, Vajzovic L, Iezzi R, Gaucher D, Arevalo JF, Gregori NZ, Grisanti S, Özmert E, Yoon YH, Kokame GT, Lim JI, Szurman P, de Juan E, Rezende FA, Salzmann J, Richard G, Huang SS, Merlini F, Patel U, Cruz C, Greenberg RJ, Justus S, Cinelli L, Humayun MS. ADVERSE EVENTS OF THE ARGUS II RETINAL PROSTHESIS: Incidence, Causes, and Best Practices for Managing and Preventing Conjunctival Erosion. Retina 2020; 40:303-311. [PMID: 31972801 DOI: 10.1097/iae.0000000000002394] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE To analyze and provide an overview of the incidence, management, and prevention of conjunctival erosion in Argus II clinical trial subjects and postapproval patients. METHODS This retrospective analysis followed the results of 274 patients treated with the Argus II Retinal Prosthesis System between June 2007 and November 2017, including 30 subjects from the US and European clinical trials, and 244 patients in the postapproval phase. Results were gathered for incidence of a serious adverse event, incidence of conjunctival erosion, occurrence sites, rates of erosion, and erosion timing. RESULTS Overall, 60% of subjects in the clinical trial subjects versus 83% of patients in the postapproval phase did not experience device- or surgery-related serious adverse events. In the postapproval phase, conjunctival erosion had an incidence rate of 6.2% over 5 years and 11 months. In 55% of conjunctival erosion cases, erosion occurred in the inferotemporal quadrant, 25% in the superotemporal quadrant, and 20% in both. Sixty percent of the erosion events occurred in the first 15 months after implantation, and 85% within the first 2.5 years. CONCLUSION Reducing occurrence of conjunctival erosion in patients with the Argus II Retinal Prosthesis requires identification and minimization of risk factors before and during implantation. Implementing inverted sutures at the implant tabs, use of graft material at these locations as well as Mersilene rather than nylon sutures, and accurate Tenon's and conjunctiva closure are recommended for consideration in all patients.
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Affiliation(s)
- Stanislao Rizzo
- Azienda Ospedaliera Universitaria Careggi, Department of Medicine and Translational Surgery, University of Florence, Florence, Italy
| | - Pierre-Olivier Barale
- Sorbonne University, UPMC Univ Paris 06, INSERM U968, CNRS UMR 7210, Institute of Vision, Paris, France
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, Paris, France
| | - Sarah Ayello-Scheer
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, Paris, France
| | - Robert G Devenyi
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
- Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada
| | - Marie-Noëlle Delyfer
- Inserm, Bordeaux Population Health Research Center, Team LEHA, University of Bordeaux, Bordeaux, France
- Department of Ophthalmology, Bordeaux University Hospital, Bordeaux, France
| | - Jean-François Korobelnik
- Inserm, Bordeaux Population Health Research Center, Team LEHA, University of Bordeaux, Bordeaux, France
- Department of Ophthalmology, Bordeaux University Hospital, Bordeaux, France
| | | | - Alex Yuan
- Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio
| | | | - David N Zacks
- Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan
| | - James T Handa
- The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Sandra R Montezuma
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota
| | - Dara Koozekanani
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, Minnesota
| | - Paulo E Stanga
- Manchester Vision Regeneration (MVR) Lab, Manchester Royal Eye Hospital, NIHR Manchester Clinical Research Facility and Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Lyndon da Cruz
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital, London, United Kingdom
| | - Peter Walter
- Department of Ophthalmology, RWTH Aachen University, Aachen, Germany
| | - Albert J Augustin
- Department of Ophthalmology, Staedtisches Klinikum Karlsruhe, Karlsruhe, Germany
| | - Marzio Chizzolini
- Unità Operativa Complessa di Oculistica, Camposampiero-Cittadella (Padova), Padua, Italy
| | - Lisa C Olmos de Koo
- Department of Ophthalmology, UW Medicine Eye Institute, University of Washington, Seattle, Washington
| | - Allen C Ho
- The Retina Service of Wills Eye Hospital, Mid Atlantic Retina, Philadelphia, Pennsylvania, Pennsylvania
| | - Bernd Kirchhof
- Department of Retina and Vitreous Surgery, Center of Ophthalmology, University of Cologne, Cologne, Germany
| | - Paul Hahn
- New Jersey Retina, Teaneck, New Jersey
| | - Lejla Vajzovic
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina
| | - Raymond Iezzi
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, Minnesota
| | - David Gaucher
- Nouvel Hôpital Civil, University Hospitals of Strasbourg, Strasbourg, France
- Laboratory of Bacteriology (EA- 7290), The Federation of Translational Medicine of Strasbourg, University of Strasbourg, Strasbourg, France
| | - J Fernando Arevalo
- The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ninel Z Gregori
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami
| | - Salvatore Grisanti
- Department of Ophthalmology, University of Luebeck, UKSH Luebeck, Germany
| | - Emin Özmert
- Department of Ophthalmology, Ankara University Faculty of Medicine, Ankara, Turkey
| | - Young Hee Yoon
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | | | - Jennifer I Lim
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois
| | - Peter Szurman
- Knappschaft Eye Clinic Sulzbach, Knappschaft Hospital Saar, Sulzbach/Saar, Germany
| | | | - Flavio A Rezende
- Department of Ophthalmology, Hôpital Maisonneuve-Rosemont, University of Montreal, Montreal, Québec, Canada
| | - Joël Salzmann
- Department of Ophthalmology, Clinique Générale-Beaulieu, Geneva, Switzerland
| | - Gisbert Richard
- Department of Ophthalmology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | | | | | - Uday Patel
- Second Sight Medical Products, Inc, Sylmar, California
| | - Cynthia Cruz
- Second Sight Medical Products, Inc, Sylmar, California
| | | | | | - Laura Cinelli
- Azienda Ospedaliera Universitaria Careggi, Department of Medicine and Translational Surgery, University of Florence, Florence, Italy
| | - Mark S Humayun
- USC Institute for Biomedical Therapeutics, USC Roski Eye Institute, University of Southern California, Los Angeles, California; and
- Department of Ophthalmology, Keck School of Medicine, University of Southern California, Los Angeles, California
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Rizzo S, Barale PO, Ayello-Scheer S, Devenyi RG, Delyfer MN, Korobelnik JF, Rachitskaya A, Yuan A, Jayasundera KT, Zacks DN, Handa JT, Montezuma SR, Koozekanani D, Stanga P, da Cruz L, Walter P, Augustin AJ, Olmos de Koo LC, Ho AC, Kirchhof B, Hahn P, Vajzovic L, Iezzi R, Gaucher D, Arevalo JF, Gregori NZ, Wiedemann P, Özmert E, Lim JI, Rezende FA, Huang SS, Merlini F, Patel U, Greenberg RJ, Justus S, Bacherini D, Cinelli L, Humayun MS. Hypotony and the Argus II retinal prosthesis: causes, prevention and management. Br J Ophthalmol 2019; 104:518-523. [DOI: 10.1136/bjophthalmol-2019-314135] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 06/23/2019] [Accepted: 06/24/2019] [Indexed: 01/15/2023]
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da Cruz L, Coley BF, Dorn J, Merlini F, Filley E, Christopher P, Chen FK, Wuyyuru V, Sahel J, Stanga P, Humayun M, Greenberg RJ, Dagnelie G. The Argus II epiretinal prosthesis system allows letter and word reading and long-term function in patients with profound vision loss. Br J Ophthalmol 2013; 97:632-6. [PMID: 23426738 PMCID: PMC3632967 DOI: 10.1136/bjophthalmol-2012-301525] [Citation(s) in RCA: 204] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Retinal prosthesis systems (RPS) are a novel treatment for profound vision loss in outer retinal dystrophies. Ideal prostheses would offer stable, long-term retinal stimulation and reproducible spatial resolution in a portable form appropriate for daily life. METHODS We report a prospective, internally controlled, multicentre trial of the Argus II system. Twenty-eight subjects with light perception vision received a retinal implant. Controlled, closed-group, forced-choice letter identification, and, open-choice two-, three- and four-letter word identification tests were carried out. RESULTS The mean±SD percentage correct letter identification for 21 subjects tested were: letters L, T, E, J, F, H, I, U, 72.3±24.6% system on and 17.7±12.9% system off; letters A, Z, Q, V, N, W, O, C, D, M, 55.0±27.4% system on and 11.8%±10.7% system off, and letters K, R, G, X, B, Y, S, P, 51.7±28.9% system on and 15.3±7.4% system off. (p<0.001 for all groups). A subgroup of six subjects was able to consistently read letters of reduced size, the smallest measuring 0.9 cm (1.7°) at 30 cm, and four subjects correctly identify unrehearsed two-, three- and four-letter words. Average implant duration was 19.9 months. CONCLUSIONS Multiple blind subjects fitted with the Argus II system consistently identified letters and words using the device, indicating reproducible spatial resolution. This, in combination with stable, long-term function, represents significant progress in the evolution of artificial sight.
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Affiliation(s)
- Lyndon da Cruz
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital, 162 City Road, London EC1V 2PD, UK.
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Terrier A, Ramondetti S, Merlini F, Pioletti DD, Farron A. Biomechanical consequences of humeral component malpositioning after anatomical total shoulder arthroplasty. J Shoulder Elbow Surg 2010; 19:1184-90. [PMID: 20951609 DOI: 10.1016/j.jse.2010.06.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Revised: 06/15/2010] [Accepted: 06/18/2010] [Indexed: 02/01/2023]
Abstract
HYPOTHESIS We hypothesized that the malpositioning of the humeral component can preclude the long-term success of anatomical total shoulder arthroplasty. The goal of this study was to evaluate the mechanical consequences of superior and inferior malpositioning of the humeral head. MATERIALS AND METHODS A numerical musculoskeletal model of the shoulder joint allowing natural humeral head translation was used to simulate a loaded abduction movement controlled by muscular activation. An inferior and superior malpositioning of 5 mm were compared to an optimal positioning. Impingements, articular contact pattern, and cement stress were evaluated. RESULTS Inferior malpositioning of the humeral head induced impingement and limited the abduction level, while superior malpositioning increased the subluxation risk. Both inferior and superior malpositioning increased the stress level within the cement mantle. DISCUSSION This numerical study highlights the importance of an anatomical reconstruction of the glenohumeral surfaces for the success rate of anatomical total shoulder arthroplasty.
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Affiliation(s)
- Alexandre Terrier
- Laboratory of Biomechanical Orthopedics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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Terrier A, Kochbeck SH, Merlini F, Gortchacow M, Pioletti DP, Farron A. Tightening force and torque of nonlocking screws in a reverse shoulder prosthesis. Clin Biomech (Bristol, Avon) 2010; 25:517-22. [PMID: 20417999 DOI: 10.1016/j.clinbiomech.2010.03.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Revised: 03/19/2010] [Accepted: 03/23/2010] [Indexed: 02/07/2023]
Abstract
BACKGROUND Reversed shoulder arthroplasty is an accepted treatment for glenohumeral arthritis associated to rotator cuff deficiency. For most reversed shoulder prostheses, the baseplate of the glenoid component is uncemented and its primary stability is provided by a central peg and peripheral screws. Because of the importance of the primary stability for a good osteo-integration of the baseplate, the optimal fixation of the screws is crucial. In particular, the amplitude of the tightening force of the nonlocking screws is clearly associated to this stability. Since this force is unknown, it is currently not accounted for in experimental or numerical analyses. Thus, the primary goal of this work is to measure this tightening force experimentally. In addition, the tightening torque was also measured, to estimate an optimal surgical value. METHODS An experimental setup with an instrumented baseplate was developed to measure simultaneously the tightening force, tightening torque and screwing angle, of the nonlocking screws of the Aquealis reversed prosthesis. In addition, the amount of bone volume around each screw was measured with a micro-CT. Measurements were performed on 6 human cadaveric scapulae. FINDINGS A statistically correlated relationship (p<0.05, R=0.83) was obtained between the maximal tightening force and the bone volume. The relationship between the tightening torque and the bone volume was not statistically significant. INTERPRETATION The experimental relationship presented in this paper can be used in numerical analyses to improve the baseplate fixation in the glenoid bone.
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Affiliation(s)
- A Terrier
- Laboratory of Biomechanical Orthopedics, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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Terrier A, Kochbeck S, Merlini F, Gortchacow M, Farron A, Pioletti D. Reverse shoulder arthroplasty: compression screw force. Comput Methods Biomech Biomed Engin 2009. [DOI: 10.1080/10255840903097830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Abstract
Wear of polyethylene is associated with aseptic loosening of orthopaedic implants and has been observed in hip and knee prostheses and anatomical implants for the shoulder. The reversed shoulder prostheses have not been assessed as yet. We investigated the volumetric polyethylene wear of the reversed and anatomical Aequalis shoulder prostheses using a mathematical musculoskeletal model. Movement and joint stability were achieved by EMG-controlled activation of the muscles. A non-constant wear factor was considered. Simulated activities of daily living were estimated from in vivo recorded data. After one year of use, the volumetric wear was 8.4 mm3 for the anatomical prosthesis, but 44.6 mm3 for the reversed version. For the anatomical prosthesis the predictions for contact pressure and wear were consistent with biomechanical and clinical data. The abrasive wear of the polyethylene in reversed prostheses should not be underestimated, and further analysis, both experimental and clinical, is required.
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Affiliation(s)
- A. Terrier
- École Polytechnique Fédérale de Lausanne, Station 15, 1015 Lausanne, Switzerland
| | - F. Merlini
- École Polytechnique Fédérale de Lausanne, Station 15, 1015 Lausanne, Switzerland
| | - D. P. Pioletti
- École Polytechnique Fédérale de Lausanne, Station 15, 1015 Lausanne, Switzerland
| | - A. Farron
- Department of Musculoskeletal Medicine, University Hospital Centre and University of Lausanne, Rue du Bugnon, 1011 Lausanne, Switzerland
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Stadelmann VA, Hocke J, Verhelle J, Forster V, Merlini F, Terrier A, Pioletti DP. 3D strain map of axially loaded mouse tibia: a numerical analysis validated by experimental measurements. Comput Methods Biomech Biomed Engin 2009; 12:95-100. [PMID: 18651261 DOI: 10.1080/10255840903077287] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
A combined experimental/numerical study was performed to calculate the 3D octahedral shear strain map in a mouse tibia loaded axially. This study is motivated by the fact that the bone remodelling analysis, in this in vivo mouse model should be performed at the zone of highest mechanical stimulus to maximise the measured effects. Accordingly, it is proposed that quantification of bone remodelling should be performed at the tibial crest and at the distal diaphysis. The numerical model could also be used to furnish a more subtle analysis as a precise correlation between local strain and local biological response can be obtained with the experimentally validated numerical model.
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Affiliation(s)
- Vincent A Stadelmann
- Laboratory of Biomechanical Orthopedics EPFL-HOSR, Institute of Translational Biomechanics, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
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Stadelmann VA, Hocké J, Verhelle J, Forster V, Merlini F, Terrier A, Pioletti DP. 3D strain map of axially loaded mouse tibia: a numerical analysis validated by experimental measurements. Comput Methods Biomech Biomed Engin 2009. [DOI: 10.1080/10255840802178053] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
Reversed shoulder prostheses are increasingly being used for the treatment of glenohumeral arthropathy associated with a deficient rotator cuff. These non-anatomical implants attempt to balance the joint forces by means of a semi-constrained articular surface and a medialised centre of rotation. A finite element model was used to compare a reversed prosthesis with an anatomical implant. Active abduction was simulated from 0 degrees to 150 degrees of elevation. With the anatomical prosthesis, the joint force almost reached the equivalence of body weight. The joint force was half this for the reversed prosthesis. The direction of force was much more vertically aligned for the reverse prosthesis, in the first 90 degrees of abduction. With the reversed prosthesis, abduction was possible without rotator cuff muscles and required 20% less deltoid force to achieve it. This force analysis confirms the potential mechanical advantage of reversed prostheses when rotator cuff muscles are deficient.
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Affiliation(s)
- A Terrier
- Laboratory of Biomechanical Orthopedics, Station 15, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
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Terrier A, Merlini F, Farron A. CONTACT PATTERN AT THE GLENOHUMERAL JOINT AFTER REVERSED SHOULDER ARTHOPLASTY. J Biomech 2008. [DOI: 10.1016/s0021-9290(08)70175-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Terrier A, Merlini F, Farron A. Shoulder arthroplasty: drawback of glenoid tilting. Comput Methods Biomech Biomed Engin 2008. [DOI: 10.1080/10255840802298984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Penzo C, Valgimigli M, Malagutti P, Merlini F, Pellegrino L, Ferrari R. Use of granulocyte-colony stimulating factor during acute myocardial infarction to enhance bone marrow stem cell mobilization in humans. J Mol Cell Cardiol 2007. [DOI: 10.1016/j.yjmcc.2007.03.202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Terrier A, Reist A, Merlini F, Farron A. ROTATOR CUFF DEFICIENCY ASSOCIATED TO TOTAL SHOULDER ARTHOPLASTY. J Biomech 2007. [DOI: 10.1016/s0021-9290(07)70143-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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