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Sample records for cementless acetabular components

  1. High-precision measurements of cementless acetabular components using model-based RSA: an experimental study

    DEFF Research Database (Denmark)

    Baad-Hansen, Thomas; Kold, Søren; Kaptein, Bart L;

    2007-01-01

    BACKGROUND: In RSA, tantalum markers attached to metal-backed acetabular cups are often difficult to detect on stereo radiographs due to the high density of the metal shell. This results in occlusion of the prosthesis markers and may lead to inconclusive migration results. Within the last few years......, new software systems have been developed to solve this problem. We compared the precision of 3 RSA systems in migration analysis of the acetabular component. MATERIAL AND METHODS: A hemispherical and a non-hemispherical acetabular component were mounted in a phantom. Both acetabular components...... underwent migration analyses with 3 different RSA systems: conventional RSA using tantalum markers, an RSA system using a hemispherical cup algorithm, and a novel model-based RSA system. RESULTS: We found narrow confidence intervals, indicating high precision of the conventional marker system and model...

  2. Migration measurement of acetabular components in cementless total hip arthroplasty; Messung der Pfannenwanderung bei zementfreien Hueftimplantaten

    Energy Technology Data Exchange (ETDEWEB)

    Eckardt, A.; Karbowski, A.; Schwitalle, M.; Vogel, J.; Boden, F.; Seeleitner, C. [Mainz Univ. (Germany). Orthopaedische Klinik und Poliklinik; Schunk, K. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Mayrhofer, P. [Innsbruck Univ. (Austria). Inst. fuer Mathematik und Geometrie

    1998-08-01

    Migration measurements of acetabular components using a special computer aided method (EBRA = abbrevation for the German term ``Ein-Bild-Roentgenanalyse``) were performed to evaluate early results of the implants and predict aseptic loosening. Methods: Standard ap-radiographs of the pelvis were marked, specific points were digitised. Simulating the spatial situation the programme computes lengitudinal and vertical migration of the cup. 74 acetabular components in 71 patients could be studied by migration measurements. Results: 14 patients showed migration of more than 1 mm, which is the confidence limit of this method. Each of these patients showed diverse reasons for the migration, i.e. osteoporosis of the acetabular bone stock or problems concerning the surgical technique which means malposition of the cup or insufficient reaming of the bone. There were some patients with severe congenital dysplasia of the hip and in some cases the inclination angle of the cup was too great. Conclusion: The technique applied for measuring migration of acetabular components can be useful for evaluating early instability of the implant and can be helpful in detecting problems concerning the surgical technique. (orig.) [Deutsch] Mittels der Ein-Bild-Roentgenanalyse wurden Pfannenwanderungen nach Implantation von zementfreien, sphaerischen Hueftgelenkspfannen erfasst, um Praediktoren fuer die langfristige Prognose der Implantate zu evaluieren. Methoden: Nach Markierung von Referenzpunkten in den Beckenuebersichtsaufnahmen wurden diese digitalisiert, vom Programm verrechnet und die Wanderung des Implantats im Verlauf angegeben. Bei 71 Patienten wurden von 74 Pfannen ueber einen Mindestnachuntersuchungszeitraum von 12 Monaten Migrationsmessungen durchgefuehrt. Das Konfidenzintervall der Methode liegt bei <1 mm. Bei jedem dieser Patienten fanden sich Hinweise entweder auf ein schlechtes Knochenlager, auf operationsbedingte Probleme, wenn keine ausreichende Primaerstabilitaet der Pfanne

  3. Three-dimensional model of cementless acetabular cup migration

    Czech Academy of Sciences Publication Activity Database

    Jíra, J.; Jiroušek, Ondřej; Jírová, Jitka; Micka, Michal

    Lisbon : CivilComp Press, 2004 - (Tooping, B.; Mota Soares, C.), s. 699 ISBN 0-948749-93-8. [The Seventh International Conference on Computational Structures Technology. Lisabon (PT), 07.09.2004-09.09.2004] Institutional research plan: CEZ:AV0Z2071913 Keywords : loosening and migration of cementless acetabular cup * pelvis * FE model Subject RIV: FI - Traumatology, Orthopedics

  4. Delayed cementless total hip arthroplasty for neglected dislocation of hip combined with complex acetabular fracture and deficient bone stock

    Directory of Open Access Journals (Sweden)

    Gavaskar Ashok S

    2012-12-01

    Full Text Available 【Abstract】Total hip arthroplasty (THA for an un-treated acetabular fracture is technically challenging and the long-term result is not so favorable. A 45-year-old fe-male patient with untreated column and comminuted poste-rior wall fracture of the acetabulum was treated in our insti-tution by reconstruction of the posterior wall using iliac strut autograft and plate stabilization of the posterior col-umn with cancellous grafting and cementless THA in a single stage. At 3 years’ follow-up, the patient was independently mobile without limb length discrepancy. Radiological evalu-ation showed well integrated components and bone grafts. No evidence of aseptic loosening or osteolysis was found. This report aims to emphasize that bony acetabular recon-struction allows the use of primary hip components, which improves prosthesis longevity and preserves bone stock for a future revision. Key words: Acetabulum; Fractures, bone; Hip dislocation; Arthroplasty, replacement, hip

  5. Placement of the acetabular component.

    Science.gov (United States)

    Beverland, D E; O'Neill, C K J; Rutherford, M; Molloy, D; Hill, J C

    2016-01-01

    Ideal placement of the acetabular component remains elusive both in terms of defining and achieving a target. Our aim is to help restore original anatomy by using the transverse acetabular ligament (TAL) to control the height, depth and version of the component. In the normal hip the TAL and labrum extend beyond the equator of the femoral head and therefore, if the definitive acetabular component is positioned such that it is cradled by and just deep to the plane of the TAL and labrum and is no more than 4mm larger than the original femoral head, the centre of the hip should be restored. If the face of the component is positioned parallel to the TAL and psoas groove the patient specific version should be restored. We still use the TAL for controlling version in the dysplastic hip because we believe that the TAL and labrum compensate for any underlying bony abnormality. The TAL should not be used as an aid to inclination. Worldwide, > 75% of surgeons operate with the patient in the lateral decubitus position and we have shown that errors in post-operative radiographic inclination (RI) of > 50° are generally caused by errors in patient positioning. Consequently, great care needs to be taken when positioning the patient. We also recommend 35° of apparent operative inclination (AOI) during surgery, as opposed to the traditional 45°. PMID:26733639

  6. Initial stability of cementless acetabular cups: press-fit and screw fixation interaction—an in vitro biomechanical study

    OpenAIRE

    Tabata, Tomonori; Kaku, Nobuhiro; Hara, Katsutoshi; Tsumura, Hiroshi

    2014-01-01

    Background Press-fit and screw fixation are important technical factors to achieve initial stability of a cementless acetabular cup for good clinical results of total hip arthroplasty. However, how these factors affect one another in initial cup fixation remains unclear. Therefore, this study aimed to evaluate the mutual influence between press-fit and screw fixation on initial cup stability. Methods Foam bone was subjected to exact hemispherical-shape machining to diameters of 48, 48.5 and 4...

  7. Wear of highly crosslinked polyethylene acetabular components

    OpenAIRE

    Callary, Stuart A.; Solomon, Lucian B; Holubowycz, Oksana T; Campbell, David G; Munn, Zachary; Howie, Donald W.

    2015-01-01

    Background and purpose Wear rates of highly crosslinked polyethylene (XLPE) acetabular components have varied considerably between different published studies. This variation is in part due to the different techniques used to measure wear and to the errors inherent in measuring the relatively low amounts of wear in XLPE bearings. We undertook a scoping review of studies that have examined the in vivo wear of XLPE acetabular components using the most sensitive method available, radiostereometr...

  8. The crescent sign: dissociation of the polyethylene liner from a modular acetabular component in total hip arthroplasty

    International Nuclear Information System (INIS)

    To study whether there was a common pattern of clinical symptoms, signs and radiographic features for the dissociation of the polyethylene liner from an acetabular component and to postulate reasons for these features. Retrospective study of notes and radiographs of cases of revision hip arthroplasty for polyethylene liner dissociation of the cementless Harris-Galante I porous-coated acetabular component (Zimmer Inc, Warsaw, IN) at the Avon Orthopaedic Centre, Bristol, UK and St. Mary's Hospital, Bristol, UK between 1995 and 2004. Patients were contacted to confirm preoperative symptoms. Nine cases of late polyethylene liner dissociation of this prosthesis have been revised in these institutions. All patients presented with a reduction in mobility, groin pain and limp. Eight patients reported an audible noise on hip movement. In all cases, radiographs showed radiolucency medial to the femoral neck in association with an eccentrically placed femoral head showing contact with the acetabular metal shell, which we have termed the ''crescent sign.'' There is a typical clinical presentation in this study. The diagnosis can be made from a single anteroposterior pelvic radiograph without the need for previous films for comparison, or the need for arthrography. Clinicians should look specifically for the crescent sign when an eccentrically placed femoral head has been noted, in order to differentiate the more unusual diagnosis of dissociation from that of polyethylene wear. Early revision surgery can prevent damage to the femoral head and metal acetabular shell, thus reducing the complexity of revision surgery. (orig.)

  9. Radiographic evaluation of HDPE cemented and cementless Lord and An.C.A. screwed acetabular models.

    Science.gov (United States)

    Toni, A; Sudanese, A; Viceconti, M; Montina, P P; Ciaroni, D; Calista, F; Terzi, S; Giunti, A

    1992-01-01

    A total of 187 alumina screwed porous-ceramic coated sockets (An.C.A.), 48 screwed smooth-surfaced Lord sockets, and 251 cemented polyethylene sockets were radiographically evaluated at an average follow-up of 30, 51 and 96 months respectively. After 6 years the Lord prostheses revealed a 38% incidence of loosening, similar to that observed for cemented sockets 10-12 years after surgery. The An.C.A. prostheses revealed radiographic loosening equal to 12% (6 cases) in the first 50 implants, and only 0.7% in the remaining 137 cases: overall, the An.C.A. acetabular prosthesis revealed an index of radiographic loosening equal to 3.3% (7/187). To guarantee "osteointegration" of the porous coating of An.C.A. sockets optimal stability must be obtained when the prosthesis is screwed in. Because the mid-term follow-up for this clinical experience is relatively short (30 months), an opinion on the reliability of the screwed "porous" sockets must await confirmation. PMID:1297574

  10. Initial mechanical stability of cementless highly-porous titanium tibial components

    Energy Technology Data Exchange (ETDEWEB)

    Stone, Timothy Brandon [Los Alamos National Laboratory; Amer, Luke D [Los Alamos National Laboratory; Warren, Christopher P [Los Alamos National Laboratory; Cornwell, Phillip [Los Alamos National Laboratory; Meneghini, R Michael [UNIV OF CONNECTICUT HEALTH CENTER

    2008-01-01

    Cementless fixation in total knee replacement has seen limited use since reports of early failure surfaced in the late 80s and early 90s. However the emergence of improved biomaterials, particularly porous titanium and tantalum, has led to a renewed interest in developing a cementless tibial component to enhance long-term survivorship of the implants. Cement is commonly employed to minimize micromotion in new implants but represents a weak interface between the implant and bone. The elimination of cement and application of these new biomaterials, which theoretically provide improved stability and ultimate osseointegration, would likely result in greater knee replacement success. Additionally, the removal of cement from the procedure would help minimize surgical durations and get rid of the time needed for curing, thereby the chance of infection. The purpose of this biomechanical study was twofold. The first goal was to assess whether vibration analysis techniques can be used to evaluate and characterize initial mechanical stability of cementless implants more accurately than the traditional method of micromotion determination, which employs linear variable differential transducers (LVDTs). Second, an evaluative study was performed to determine the comparative mechanical stability of five designs of cementless tibial components under mechanical loading designed to simulate in vivo forces. The test groups will include a cemented Triathlon Keeled baseplate control group, three different 2-peg cementless baseplates with smooth, mid, and high roughnesses and a 4-peg cement/ess baseplate with mid-roughness.

  11. Contact Stress Analysis of Acetabular Component and Pelvic Bone

    Czech Academy of Sciences Publication Activity Database

    Vyčichl, Jan; Jiroušek, Ondřej; Jírová, Jitka

    Wroclaw : Oficyna Wydawnicza Politechniki Wroclawskiej, 2006 - (Grygier, D.), s. 73-74 ISSN 1732-0240. [ Students ' Scientific Conference of Biomedical Engineeting /2/. Szklarska Poreba (PL), 20.04.2006-23.04.2006] R&D Projects: GA AV ČR(CZ) IAA200710504 Institutional research plan: CEZ:AV0Z20710524 Keywords : pelvic bone * acetabular component * stress analysis * finite element method Subject RIV: EI - Biotechnology ; Bionics

  12. Migration pattern of cementless press fit cups in the presence of stabilizing screws in total hip arthroplasty

    Directory of Open Access Journals (Sweden)

    Zilkens C

    2011-03-01

    Full Text Available Abstract The aim of this study was to evaluate the initial acetabular implant stability and late acetabular implant migration in press fit cups combined with screw fixation of the acetabular component in order to answer the question whether screws are necessary for the fixation of the acetabular component in cementless primary total hip arthroplasty. One hundred and seven hips were available for follow-up after primary THA using a cementless, porous-coated acetabular component. A total of 631 standardized radiographs were analyzed digitally by the "single-film-x-ray-analysis" method (EBRA. One hundred 'and one (94.4% acetabular components did not show significant migration of more than 1 mm. Six (5.6% implants showed migration of more than 1 mm. Statistical analysis did not reveal preoperative patterns that would identify predictors for future migration. Our findings suggest that the use of screw fixation for cementless porous- coated acetabular components for primary THA does not prevent cup migration.

  13. Migration pattern of cementless press fit cups in the presence of stabilizing screws in total hip arthroplasty.

    Science.gov (United States)

    Zilkens, C; Djalali, S; Bittersohl, B; Kälicke, T; Kraft, C N; Krauspe, R; Jäger, Marcus

    2011-03-28

    The aim of this study was to evaluate the initial acetabular implant stability and late acetabular implant migration in press fit cups combined with screw fixation of the acetabular component in order to answer the question whether screws are necessary for the fixation of the acetabular component in cementless primary total hip arthroplasty. One hundred and seven hips were available for follow-up after primary THA using a cementless, porous-coated acetabular component. A total of 631 standardized radiographs were analyzed digitally by the "single-film-x-ray-analysis" method (EBRA). One hundred and one (94.4 %) acetabular components did not show significant migration of more than 1 mm. Six (5.6%) implants showed migration of more than 1 mm. Statistical analysis did not reveal preoperative patterns that would identify predictors for future migration. Our findings suggest that the use of screw fixation for cementless porous-coated acetabular components for primary THA does not prevent cup migration. PMID:21486725

  14. Options for acetabular fixation surfaces.

    Science.gov (United States)

    Klika, Alison K; Murray, Trevor G; Darwiche, Hussein; Barsoum, Wael K

    2007-01-01

    Aseptic loosening is the most common cause for revision total hip arthroplasty (THA). Due to poor long-term results with cemented acetabular components, cementless implants that rely on biologic fixation became popular in the United States for both primary and revision procedures in the early 1980s. Cementless acetabular components used in THA have been reported to have superior radiographic performance compared with cemented fixation, although the optimal method of acetabular fixation remains controversial. Cementless acetabular components require initial implant stability to allow for bone ingrowth and remodeling into the acetabular shell, providing long-term durability of the prosthesis. Many improved implant materials are available to facilitate bone growth and remodeling, including the 3 most common surface treatments; fibermesh, sintered beads, and plasma spray coatings. Recently added to these are porous metal surfaces, which have increased porosity and optimal pore sizes when compared with titanium fibermesh. The most studied of these materials is the titanium fibermesh fixation surface, which has demonstrated a mechanical failure rate of 1% at 10 to 15 years. This technology utilizes the diffusion bonding process to attach fiber metal pads to a titanium substrate using heat and pressure. The sintered bead fixation surface offers a porous coating of various sizes of spherical beads, achieved by the sintering process, and has been shown to provide long-term fixation. While there are less long-term published data regarding the titanium plasma spray surface, its early results have provided evidence of its durability, even in the face of significant osteolysis. The most recently added alternative fixation surface is porous tantalum metal, which offers potentially greater bone ingrowth and bone graft incorporation due to its high porosity (80%) and low modulus of elasticity (3 MPa). Porous tantalum implants have shown early favorable clinical results and have

  15. Acetabular Dysplasia and Surgical Approaches Other Than Direct Anterior Increases Risk for Malpositioning of the Acetabular Component in Total Hip Arthroplasty

    DEFF Research Database (Denmark)

    Gromov, Kirill; Greene, Meridith E; Huddleston, James I;

    2016-01-01

    BACKGROUND: Persistent acetabular dysplasia (AD) after periacetabular osteotomy has been hypothesized to increase the risk for malpositioning of the acetabular component. In this study, we investigate whether AD is an independent risk factor for cup malpositioning during primary total hip...... arthroplasty (THA). METHODS: Patient demographics, surgical approach, presence of AD assessed using the lateral center-edge angle, and acetabular cup positioning determined using Martell Hip Analysis Suite were investigated in 836 primary THA patients enrolled in a prospective multicenter study. RESULTS: We...

  16. Custom acetabular component design with interactive two-dimensional CT

    International Nuclear Information System (INIS)

    This paper reports on a revision of failed acetabular components that must accommodate existing segmental and cavitary bone defects and global loss of bone stock. Two-dimensional CT can be used to determine which patients may benefit from a custom acetabulum and to design such a prosthesis. Ninety-one sequential failed hip arthroplasties were reviewed to find 12 potential custom cup candidates, of whom seven underwent CT assessment and subsequent cup design and placement. Coronal and sagittal CT was used to review existing bone stock and bone defects, to measure and map the contour of the defect into which the new cup must fit and to determine the precise placement, angulation, and depth of screw holes to provide purchase for the new cup. A template was produced for approval, followed by cup manufacture and placement

  17. Modified cementless total coxofemoral prosthesis: development, implantation and clinical evaluation

    Directory of Open Access Journals (Sweden)

    S.A. Arias

    2013-12-01

    Full Text Available The aim of this study was to modify canine coxofemoral prostheses and the clinical evaluation of the implantation. Fifteen canine hips and femora of cadavers were used in order to study the surface points of modification in prostheses and develop a perforation guide. Femoral stems and acetabular components were perforated and coated with biphasic calcium phosphate layer. Twelve young adult male mongrel dogs were implanted with coxofemoral prostheses. Six were operated upon and implanted with cemented canine modular hip prostheses, establishing the control group. The remaining six were implanted with a novel design of cementless porous tricalcic phosphate-hydroxyapatite coated hip prostheses. Clinical and orthopedic performance, complications, and thigh muscular hypotrophy were assessed up to the 120th post-operatory day. After 120 days, animals with cementless prostheses had similar clinical and orthopedic performance compared to the cemented group despite the increased pain thigh hypotrophy. Animals that underwent cementless hip prosthesis evidenced more pain, compared to animals with cemented hip prosthesis that required longer recuperation time. No luxations, two fractures and two isquiatic neurapraxies were identified in the course of the study. Using both the cemented and the bioactive coated cementless model were suitable to dogs, showing clinical satisfactory results. Osseointegration and biological fixation were observed in the animals with the modified cementless hip prosthesis.

  18. 21 CFR 888.3320 - Hip joint metal/metal semi-constrained, with a cemented acetabular component, prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented acetabular component, prosthesis. 888.3320 Section 888.3320 Food and Drugs FOOD AND DRUG..., prosthesis. (a) Identification. A hip joint metal/metal semi-constrained, with a cemented acetabular component, prosthesis is a two-part device intended to be implanted to replace a hip joint. The...

  19. 21 CFR 888.3330 - Hip joint metal/metal semi-constrained, with an uncemented acetabular component, prosthesis.

    Science.gov (United States)

    2010-04-01

    ... uncemented acetabular component, prosthesis. 888.3330 Section 888.3330 Food and Drugs FOOD AND DRUG..., prosthesis. (a) Identification. A hip joint metal/metal semi-constrained, with an uncemented acetabular component, prosthesis is a two-part device intended to be implanted to replace a hip joint. The...

  20. Acetabular component migration in total hip arthroplasty using CT and a semiautomated program for volume merging

    International Nuclear Information System (INIS)

    Purpose: To develop a non-invasive method for detection of acetabular cup migration after total hip arthroplasty (THA) with a higher degree of accuracy than routine plain radiography. Material and Methods: Two CT examinations, 10 min apart, were obtained from each of 10 patients that had undergone THA. Using an in-house developed semiautomated program for volume merging, the pelves in the two examinations were fused and the acetabular cup was visually and numerically evaluated to test the method's accuracy in detecting migration. Results: In the visual evaluation of the best match a 1-mm translation of the cup was detectable. The numerical evaluation, comparing landmarks placed in the images of the acetabular cup and the head of the femur component in the two examinations, showed the mean difference in orientation of acetabular axes to be 2.5 deg, the mean distance between centre of cup face to be 2.5 mm and the mean distance between centre of the head of the prosthetic femoral component to be 1 mm. Conclusion: This method has a significantly higher accuracy than routine plain radiography in detecting acetabular cup migration and could be used in clinical practice. It gives both a visual and a numerical correlate to migration

  1. Cementless Hip Arthroplasty in Southern Iran, Midterm Outcome and Comparison of Two Designs

    Directory of Open Access Journals (Sweden)

    Gholam Hossein Shahcheraghi

    2015-09-01

    Full Text Available Background: Cementless hip prosthesis was designed to provide biologic fixation, without the use of cement. The second generation components have shown more reliable bone ingrowths and survival rates. We are reporting a midterm result of two designs of cementless prosthesis in a unique culture with different social habits and expectations. Methods: 52 primary cementless total hip arthroplasty in 42 patients with the mean age of 48.8 years were retrospectively studied. Two groups of prosthesis had been implanted: Harris-Galante II (HGII in 15 and Versys-Trilogy (V-T in 37 hips, both from Zimmer company. The patients were assessed clinically, radiographically and with Harris hip score, SF36, WOMAC, and MACTAR questionnaires, with 65 months (26-136 mean follow-up. Results: All the V-T prostheses had survived well. Eight of HG II were revised by the last follow-up in 19-102 months. All had undergone acetabular revision and 2 combined with femoral revision. Broken tines of HGII cups were seen in 4 radiographs. The 65 months overall survival was 96.2% for femoral and 84.6% for acetabular components. 90% had good or excellent Harris hip scores. The functional scores were poorer in the HG II group. Pain relief and improved walking were the two main patients’ expectations fulfilled in 97.6% and 92.8%, respectively. Conclusions: The outcome of cementless total hip arthroplasty (THA is satisfactory and comparable with the literature based on the results of function and survival of this small comparative group. The use of HGII acetabular component should be abandoned.

  2. Effect of rotator cuff dysfunction on the initial mechanical stability of cementless glenoid components

    NARCIS (Netherlands)

    D.R. Suárez (Daniel); E.R. Valstar (Edward); J.C. Linden (Jacqueline); F. van Keulen (Fred); P.M. Rozing (Piet)

    2009-01-01

    textabstractThe functional outcome of shoulder replacement is related to the condition of the rotator cuff. Rotator cuff disease is a common problem in candidates for total shoulder arthroplasty; this study relates the functional status of the rotator cuff to the initial stability of a cementless gl

  3. Large head metal-on-metal cementless total hip arthroplasty versus 28mm metal-on-polyethylene cementless total hip arthroplasty: design of a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    van Raaij Jos JAM

    2008-10-01

    Full Text Available Abstract Background Osteoarthritis of the hip is successfully treated by total hip arthroplasty with metal-on-polyethylene articulation. Polyethylene wear debris can however lead to osteolysis, aseptic loosening and failure of the implant. Large head metal-on-metal total hip arthroplasty may overcome polyethylene wear induced prosthetic failure, but can increase systemic cobalt and chromium ion concentrations. The objective of this study is to compare two cementless total hip arthroplasties: a conventional 28 mm metal-on-polyethylene articulation and a large head metal-on-metal articulation. We hypothesize that the latter arthroplasties show less bone density loss and higher serum metal ion concentrations. We expect equal functional scores, greater range of motion, fewer dislocations, fewer periprosthetic radiolucencies and increased prosthetic survival with the metal-on-metal articulation. Methods A randomized controlled trial will be conducted. Patients to be included suffer from non-inflammatory degenerative joint disease of the hip, are aged between 18 and 80 and are admitted for primary cementless unilateral total hip arthroplasty. Patients in the metal-on-metal group will receive a cementless titanium alloy acetabular component with a cobalt-chromium liner and a cobalt-chromium femoral head varying from 38 to 60 mm. Patients in the metal-on-polyethylene group will receive a cementless titanium alloy acetabular component with a polyethylene liner and a 28 mm cobalt-chromium femoral head. We will assess acetabular bone mineral density by dual energy x-ray absorptiometry (DEXA, serum ion concentrations of cobalt, chromium and titanium, self reported functional status (Oxford hip score, physician reported functional status and range of motion (Harris hip score, number of dislocations and prosthetic survival. Measurements will take place preoperatively, perioperatively, and postoperatively (6 weeks, 1 year, 5 years and 10 years. Discussion

  4. Determinación del desgaste del componente acetabular en prótesis totales de cadera. // Wear determination of acetabular component in total hip prosthesis.

    Directory of Open Access Journals (Sweden)

    G. García del Pino

    2002-01-01

    Full Text Available En este trabajo se realiza un estudio a través del Método de los Elementos Finitos “MEF” sobre el desgaste del componenteacetabular durante el ciclo de marcha y considerando algunos casos extremos de cargas como subir y bajar escaleras,levantarse de una silla, etc. Utilizando el MEF fueron modelados independientemente los componentes acetabular yfemoral de la prótesis total de cadera y puestos en contacto posteriormente. Fueron estudiadas varias posiciones delacetábulo así como diferentes casos de carga simulando pacientes con diferente peso corporal y actividades físicas. Paraevaluar los resultados se crearon rutinas en lenguaje C que organizaron los mismos para un tratamiento estadísticoposterior.Palabras claves: biomecánica, ortopedia, elementos finitos, modelación, desgaste, prótesis de cadera.___________________________________________________________________________Abstract.A wear study of acetabular component during the marching cycle, considering some extreme loads cases as: ascend anddescend stairways, get up from a seat, etc , by means of Finite Elements Method ( FEM , is carried out. The acetabular andfemoral component of the total hip prosthesis were independently modeled and placed in contact lastly. Several acetabulpositions were studied as well as different load cases, simulating patients with different body weight and different physicalactivities. To evaluate the results routines in C language were created in order to organized the same ones for a laterstatistical treatment.Key words. biomechanics, ortophedy, finite elements, modelation, wear, hip bone prosthesis.

  5. Towards the optimal design of an uncemented acetabular component using genetic algorithms

    Science.gov (United States)

    Ghosh, Rajesh; Pratihar, Dilip Kumar; Gupta, Sanjay

    2015-12-01

    Aseptic loosening of the acetabular component (hemispherical socket of the pelvic bone) has been mainly attributed to bone resorption and excessive generation of wear particle debris. The aim of this study was to determine optimal design parameters for the acetabular component that would minimize bone resorption and volumetric wear. Three-dimensional finite element models of intact and implanted pelvises were developed using data from computed tomography scans. A multi-objective optimization problem was formulated and solved using a genetic algorithm. A combination of suitable implant material and corresponding set of optimal thicknesses of the component was obtained from the Pareto-optimal front of solutions. The ultra-high-molecular-weight polyethylene (UHMWPE) component generated considerably greater volumetric wear but lower bone density loss compared to carbon-fibre reinforced polyetheretherketone (CFR-PEEK) and ceramic. CFR-PEEK was located in the range between ceramic and UHMWPE. Although ceramic appeared to be a viable alternative to cobalt-chromium-molybdenum alloy, CFR-PEEK seems to be the most promising alternative material.

  6. Total hip arthroplasty with cementless cups and femoral head autografts for patients with hip dysplasia and osteoarthritis

    Institute of Scientific and Technical Information of China (English)

    吴立东; 金礼斌; 严世贵; 杨泉森; 戴雪松; 王祥华

    2004-01-01

    Objective:To evaluate the outcome of total hip arthroplasty (THA) with cementless cups and femoral head autografts for patients with hip dysplasia and osteoarthritis.Methods: Between 1995 and 2002, we implanted 23cementless cups and femoral head autografts in 20 patients with hip dysplasia and osteoarthritis. In this study, a retrospective study was made on 21 hips in 20 patients (18females and 2 males, aged 50 years on an average) with developmental hip dysplasia treated by THA with acementless cup and femoral head autograft. The acetabular cup was placed at the level of the true acetabuinm and all the patients required autogenous femoral head grafts due to acetabular deficiency. The average rate of the acetabular cup covered by the femoral head autograft was 31%(ranging from 10% to 45%). Eight hips had less than 25%cup coverage and thirteen between 25% and 50%. The average follow-up period was 4.7 years (range, 1-8 years).The replacing outcome was evaluated by modified Harris hip score. Preoperative and follow-up radiographs were made.Results: All the autografts were united to the host bones. No autograft was collapsed or no component from the hip was loosed in all the patients. According to the modified Harris hip score, the average hip score increased from 46 before operation to 89 at the final review. Before operation, the leg-length discrepancy was greater than 2 cm in all the patients except one with bilateral hip dysplasia.After operation, only 2 out of 20 patients had a leg-length discrepancy greater than 1 cm. Three hips showed minor bone resorption in the lateral portion of the graft, which did not support the cup. Three hips developed Grade 1Brooker heterotopic ossification and one developed Grade 2.Conclusions: THA with a cementless cup and a femoral head autograft for patients with osteoarthritis resulted from hip dysplasia can result in favorable outcomes. This method can provide reliable acetabular fixation and restore the acetabular bone stock in

  7. Explicit finite element modelling of the impaction of metal press-fit acetabular components.

    Science.gov (United States)

    Hothi, H S; Busfield, J J C; Shelton, J C

    2011-03-01

    Metal press-fit cups and shells are widely used in hip resurfacing and total hip replacement procedures. These acetabular components are inserted into a reamed acetabula cavity by either impacting their inner polar surface (shells) or outer rim (cups). Two-dimensional explicit dynamics axisymmetric finite element models were developed to simulate these impaction methods. Greater impact velocities were needed to insert the components when the interference fit was increased; a minimum velocity of 2 m/s was required to fully seat a component with a 2 mm interference between the bone and outer diameter. Changing the component material from cobalt-chromium to titanium alloy resulted in a reduction in the number of impacts on the pole to seat it from 14 to nine. Of greatest significance, it was found that locking a rigid cap to the cup or shell rim resulted in up to nine fewer impactions being necessary to seat it than impacting directly on the polar surface or using a cap free from the rim of the component, as is the case with many commercial resurfacing cup impaction devices currently used. This is important to impactor design and could make insertion easier and also reduce acetabula bone damage. PMID:21485331

  8. Good performance of a titanium femoral component in cementless hip arthroplasty in younger patients: 97 arthroplasties followed for 5-11 years

    DEFF Research Database (Denmark)

    Jacobsen, Steffen; Jensen, Frank Krieger; Poulsen, Klaus;

    2003-01-01

    We performed 97 uncemented primary total hip arthroplasties in 80 patients having an average age of 50 years. The femoral implant was a titanium stem with a proximal circumferential plasma spray-coating. Three different acetabular components were used: a threaded and partly porous-coated design i...

  9. A reduction clamp for an aiming component in associated acetabular fractures

    Directory of Open Access Journals (Sweden)

    Zhang-Fu Wang

    2015-01-01

    Full Text Available Background: The treatment of acetabular fractures is complex and requires specialized equipment. However, all currently available instruments have some disadvantages. A new reduction clamp that can firmly enable reduction and not hinder subsequent fixation procedures for some special fracture types is needed. Materials and Methods: In this study, we introduce a new acetabular clamp and its preliminary clinical application in three T-shaped acetabular fractures. Results: This new clamp can successfully pull the posterior column back to the anterior column and firmly maintain the reduction. This clamp′s aiming plate can facilitate the insertion of long lag screws. The clamp is also easy to assemble and use. Conclusion: This reduction clamp is a useful instrument that can facilitate open reduction and internal fixation of acetabular fractures.

  10. Initial Results of an Acetabular Center Axis Registration Technique in Navigated Hip Arthroplasty with Deformed Acetabular Rims

    OpenAIRE

    Wada, Hiroshi; Mishima, Hajime; Yoshizawa, Tomohiro; Sugaya, Hisashi; Nishino, Tomofumi; Yamazaki, Masashi

    2016-01-01

    Background In cementless total hip arthroplasty, imageless computer-assisted navigation is usually used to register the anterior pelvic plane (APP). The accuracy of this method is influenced by the subcutaneous tissues overlying the registration landmarks. On the other hand, the acetabular center axis (ACA) is determined from the acetabular rim. Precise registration of the ACA is possible because of direct palpation using a pointer. Imageless navigation using the ACA usually targets patients ...

  11. A comparative study of "plasmacup" and "porous-coated" acetabular components: survival after 10 to 12 years of follow-up

    Directory of Open Access Journals (Sweden)

    José Ricardo Negreiros Vicente

    2010-01-01

    Full Text Available OBJECTIVES: Our primary aim was to compare the long-term survivorship rates and the rates of successful osseointegration between two different types of uncemented acetabular components. INTRODUCTION: Two types of alloys have primarily been used for the manufacture of the uncemented acetabular components: titanium-based and cobalt-based alloys. A titanium-based alloy appears to be more effective with regard to interface stress transfer to the host bone because of its lower elastic modulus relative to a cobalt-based alloy. This supposed mechanical advantage of a titanium-based alloy component motivated this comparative study. METHODS: Two uncemented acetabular components, a porous-coated acetabulum and a Plasmacup®, were compared with a focus on long-term prosthesis survivorship and the development of acetabular osseointegration. Five radiographic signs of osseointegration were evaluated at the last follow-up appointment: (1 absence of radiolucent lines, (2 presence of a superolateral buttress, (3 medial stress-shielding, (4 radial trabeculae, and (5 an inferomedial buttress. We considered the presence of any three of these radiographic signs, in the absence of acetabular dislocation or symptoms, to be indicative of successful acetabular osseointegration. RESULTS: Among 70 patients implanted with the porous-coated acetabulum, 80% achieved osseointegration over a mean follow-up time of 11.9 years versus 75.3% of the 73 patients who received a Plasmacup insert over a mean of 10.7 years. Prosthesis survivorship rates were not different between the two groups. Revision surgery due to mild or severe acetabular osteolysis, polyethylene wear, and aseptic loosening occurred in eight patients (11.4% with a PCA versus nine (12.3% with a Plasmacup. CONCLUSIONS: We conclude that, during the first ten years after surgery, there is no significant difference between these two types of uncemented cups with regard to either prosthesis survivorship or successful

  12. Do Rerevision Rates Differ After First-time Revision of Primary THA With a Cemented and Cementless Femoral Component?

    DEFF Research Database (Denmark)

    Gromov, Kirill; Pedersen, Alma B; Overgaard, Søren;

    2015-01-01

    ) and 2 years (range, 0-16 years), respectively. Survival of first revision THA, with second revision of the femur as outcome, was evaluated using hazard ratios (HRs) with 95% confidence interval (CI) adjusting for potential confounding. All patient- and surgery-related data are collected from Danish...... adjusting for the most likely confounding factors. Our data suggest that increased use of cementless fixation in primary THA may lead to inferior survivorship of first revision THA. Level III, therapeutic study....... results of future revision procedures; however, this has not been documented. The purpose of this study was to compare (1) the risk for rerevision of first revision THA; (2) the patterns of femoral bone loss at the time of first revision of primary THA; (3) the reasons for first revision of primary THA...

  13. Deformation of the Durom acetabular component and its impact on tribology in a cadaveric model--a simulator study.

    Directory of Open Access Journals (Sweden)

    Feng Liu

    Full Text Available BACKGROUND: Recent studies have shown that the acetabular component frequently becomes deformed during press-fit insertion. The aim of this study was to explore the deformation of the Durom cup after implantation and to clarify the impact of deformation on wear and ion release of the Durom large head metal-on-metal (MOM total hips in simulators. METHODS: Six Durom cups impacted into reamed acetabula of fresh cadavers were used as the experimental group and another 6 size-paired intact Durom cups constituted the control group. All 12 Durom MOM total hips were put through a 3 million cycle (MC wear test in simulators. RESULTS: The 6 cups in the experimental group were all deformed, with a mean deformation of 41.78 ± 8.86 µm. The average volumetric wear rate in the experimental group and in the control group in the first million cycle was 6.65 ± 0.29 mm(3/MC and 0.89 ± 0.04 mm(3/MC (t = 48.43, p = 0.000. The ion levels of Cr and Co in the experimental group were also higher than those in the control group before 2.0 MC. However there was no difference in the ion levels between 2.0 and 3.0 MC. CONCLUSIONS: This finding implies that the non-modular acetabular component of Durom total hip prosthesis is likely to become deformed during press-fit insertion, and that the deformation will result in increased volumetric wear and increased ion release. CLINICAL RELEVANCE: This study was determined to explore the deformation of the Durom cup after implantation and to clarify the impact of deformation on wear and ion release of the prosthesis. Deformation of the cup after implantation increases the wear of MOM bearings and the resulting ion levels. The clinical use of the Durom large head prosthesis should be with great care.

  14. Determinación del desgaste del componente acetabular en prótesis totales de cadera. // Wear determination of acetabular component in total hip prosthesis.

    OpenAIRE

    G. García del Pino; Gonçalves, E; R. Gonzáles Lima; R. Dantas Queiroz; J. L. Valín Rivera

    2002-01-01

    En este trabajo se realiza un estudio a través del Método de los Elementos Finitos “MEF” sobre el desgaste del componenteacetabular durante el ciclo de marcha y considerando algunos casos extremos de cargas como subir y bajar escaleras,levantarse de una silla, etc. Utilizando el MEF fueron modelados independientemente los componentes acetabular yfemoral de la prótesis total de cadera y puestos en contacto posteriormente. Fueron estudiadas varias posiciones delacetábulo así como diferentes cas...

  15. Cementless Hip Arthroplasty in Southern Iran, Midterm Outcome and Comparison of Two Designs

    OpenAIRE

    Gholam Hossein Shahcheraghi; Seyed Ali Hashemi

    2015-01-01

    Background: Cementless hip prosthesis was designed to provide biologic fixation, without the use of cement. The second generation components have shown more reliable bone ingrowths and survival rates. We are reporting a midterm result of two designs of cementless prosthesis in a unique culture with different social habits and expectations. Methods: 52 primary cementless total hip arthroplasty in 42 patients with the mean age of 48.8 years were retrospectively studied. Two groups of prosthe...

  16. A safe zone for acetabular component position in metal-on-metal hip resurfacing arthroplasty: winner of the 2012 HAP PAUL award.

    Science.gov (United States)

    Liu, Fei; Gross, Thomas P

    2013-08-01

    A safe zone for acetabular component positioning in hip resurfacing (RAIL: Relative Acetabular Inclination Limit) was calculated based on implant size and acetabular inclination angle (AIA). For AIA below the RAIL, there were no adverse wear failures or dislocations, and only 1% of cases with ion levels above 10 μg/L. Other than high inclination angle and small bearing size, female gender was the only other factor that correlated with high ion levels in the multivariate analysis. Seven hundred sixty-one hip resurfacing cases are included in this study. The UCLA activity score, femoral shaft angle, body mass index, weight, American Society of Anesthesiologists score, combined range of motion, diagnosis, age, gender, implant brand, AIA, bearing size, and duration of implantation were analyzed to determine the potential risk factors for elevated metal ion levels. These findings apply to sub hemispheric metal-on-metal bearings with similar coverage arcs as the Biomet and Corin hip resurfacing brands. Additional problems may occur when these bearings are connected with trunions on stems for total hip arthroplasty. PMID:23540536

  17. Development of a novel acetabular cup component for large bearing total hip arthroplasty

    OpenAIRE

    Gillard, Faye Catherine

    2014-01-01

    Total hip replacement (THR) is a successful procedure that demonstrates excellent long term survival rates in the elderly patient population. Resurfacing and large diameter bearing total hip components were introduced to improve survivorship in younger patients but problems associated with high levels of wear and component loosening has limited their acceptance in regular clinical practice. Aurora Medical Ltd (Southampton, UK) identified a need for a large diameter bearing hip replacement whi...

  18. Model Studies on Acetabular Component Migration in Total Hip Arthroplasty using CT and a Semiautomated Program for Volume Merging

    International Nuclear Information System (INIS)

    Purpose: Validation of a non-invasive CT method for detection of acetabular cup migration after total hip arthroplasty in a phantom study. Material and Methods: 26 CT examinations were obtained of a pelvic model while altering the position of the acetabular cup. Using a previously described program for volume merging, the pelvi in different examinations were fused and the 3D alterations of the position of the acetabular cup were evaluated visually and numerically and correlated to direct measurements on the model. Results: Visually, two independent examiners differentiated between 0, 1 and 2 to 3 mm migration with 100% specificity and sensitivity. Numerically, the mean error over all cases between model and CT measurements was 0.04 mm (SD ± 0.33). The mean absolute error between model and CT data was 0.26 mm (SD ± 0.19). Intra- and interobserver 95% accuracy and repeatability limits were below 0.5/0.7 mm, respectively. No significant interobserver difference occurred. The data were normally distributed and not dependent on observer. Conclusion: The accuracy of this non-invasive method out-performs routine plain radiography. The method gives both visual and numerical correlates to migration and can be used in clinical practice

  19. Analysis of migration of press-fit porous-coated acetabular components with medial lucencies using Ein-Bild-Roentegen-Analyse.

    Science.gov (United States)

    Sadeghi, Cameron; Gibson, Anthony G; Ries, Michael D

    2012-08-01

    A total of 136 patients who underwent total hip arthroplasty (154 hips) with press-fit acetabular components were evaluated for the presence of medial radiographic lucencies. Thirty patients (22.1%) demonstrated radiolucencies greater than 1 mm in zone 2 on initial postoperative films. Ein-Bild-Roentegen-Analyse (EBRA) was used to evaluate component migration over a 5-year follow-up period. Migration, measured by EBRA, was not observed during the first 6 months when the radiolucencies were noted to disappear. After 2 years, the mean total migration was 0.8 mm, and at 5 years, it was 1.6 mm. Our results indicate that disappearance of a medial radiolucency seen on early postoperative radiographs is not associated with component migration, which supports the concept that the medial radiolucency fills in with bone or represents bony remodeling around a stable implant. PMID:22177796

  20. Importance of maintaining the basic stress pathway above the acetabular dome during acetabular reconstruction.

    Science.gov (United States)

    Nie, Yong; Pei, Fuxing; Shen, Bin; Kang, Pengde; Li, Zongming

    2016-07-01

    The basic stress pathway above the acetabular dome is important for the maintenance of implant stability in press-fit acetabular reconstruction of total hip arthroplasty. However, information on the basic stress pathway and its impact factors remains unclear. The objective of this study was to investigate the effects of the orientations and positions of the acetabular component on the basic stress pathway. The basic stress pathway above the acetabular dome was defined as two parts: 3D basic trabecular bone stress distribution and quantified basic cortical bone stress level, using two subject-specific finite element normal hip models. The effects were then analysed by generating 32 reconstructed acetabular cases with different cup abduction and anteversion angles within a range of 35-50° and 10-25°, respectively, and 12 cases with different hip centre heights within a range of 0-15 mm above the acetabular dome. The 3D trabecular stress distribution decreased remarkably in all cases, while the 80% of the basic cortical bone stress level was maintained in cases when the acetabular component was positioned at 10° or 15° anteversion and 40° or 45° abduction angles. The basic stress pathway above the acetabular dome was disturbed when the superior displacement of the hip centre exceeded 5 mm above the anatomical hip centre. Positioning the acetabular component correctly contributes to maintain the stress balance between the acetabular cup and the bone during acetabular reconstruction, thus helping restore the normal hip biomechanics and preserve the stability of the implants. PMID:26469561

  1. Cementless Oxford unicompartmental knee replacement shows reduced radiolucency at one year.

    Science.gov (United States)

    Pandit, H; Jenkins, C; Beard, D J; Gallagher, J; Price, A J; Dodd, C A F; Goodfellow, J W; Murray, D W

    2009-02-01

    We randomised 62 knees to receive either cemented or cementless versions of the Oxford unicompartmental knee replacement. The implants used in both arms of the study were similar, except that the cementless components were coated with porous titanium and hydroxyapatite. The tibial interfaces were studied with fluoroscopically-aligned radiographs. At one year there was no difference in clinical outcome between the two groups. Narrow radiolucent lines were seen at the bone-implant interfaces in 75% of cemented tibial components. These were partial in 43%, and complete in 32%. In the cementless implants, partial radiolucencies were seen in 7% and complete radiolucencies in none. These differences are statistically significant (p < 0.0001) and imply satisfactory bone ingrowth into the cementless implants. PMID:19190051

  2. Loosening After Acetabular Revision

    DEFF Research Database (Denmark)

    Beckmann, Nicholas A.; Weiss, Stefan; Klotz, Matthias C.M.;

    2014-01-01

    The best method of revision acetabular arthroplasty remains unclear. Consequently, we reviewed the literature on the treatment of revision acetabular arthroplasty using revision rings (1541 cases; mean follow-up (FU) 5.7 years) and Trabecular Metal, or TM, implants (1959 cases; mean FU 3.7 years)...

  3. Computed tomography analysis of acetabular anteversion and abduction

    Energy Technology Data Exchange (ETDEWEB)

    Stem, Eric S. [Mayo Clinic, Department of Orthopedic Surgery, Jacksonville, FL (United States); South Carolina Sports Medicine and Orthopaedic Center, North Charleston, SC (United States); O' Connor, Mary I. [Mayo Clinic, Department of Orthopedic Surgery, Jacksonville, FL (United States); Kransdorf, Mark J. [Mayo Clinic, Department of Radiology, Jacksonville, FL (United States); Crook, Julia [Mayo Clinic, Biostatistic Unit, Jacksonville, FL (United States)

    2006-06-15

    The purpose of this study is to define the normal range of acetabular abduction and anteversion in relation to pelvic anatomy as depicted on conventional CT scan. We retrospectively reviewed 100 pelvic CT scans performed on patients presenting for evaluation of non-orthopaedic pathology. The study group consisted of 58 women and 42 men, aged between 18 and 88 years. Standard imaging protocol included an anteroposterior (AP) topogram with contiguous 5-mm thick axial images from the superior margin of the iliac crest to the lesser trochanter of the femur. The acetabular abduction was measured from the AP topogram by obtaining the angle between a line drawn from the acetabular teardrop to the lateral acetabular margin and a horizontal line between the ischial tuberosities. Acetabular anteversion was measured on axial images at the level of the mid-femoral head. We found the mean acetabular abduction to be 39 degrees (standard deviation 4 degrees, range 27 to 51 degrees) and the mean acetabular anteversion to be 23 degrees (standard deviation 5 degrees, range 12 to 39 degrees). Data suggests that acetabular anteversion may average 2.7 degrees lower in males than females and increase slightly with age, while abduction may tend to decrease with age. Ninety percent of patients had acetabular abduction between 31 and 46 degrees; the 90% central range for acetabular anteversion was estimated to be from 14 to 31 degrees. CT scanning is useful in accurately defining the normal range of acetabular abduction and antiversion. Knowledge of this normal anatomy will allow accurate assessment of acetabular component position as delineated on conventional CT scanning. (orig.)

  4. Cementless Hydroxyapatite Coated Hip Prostheses

    Directory of Open Access Journals (Sweden)

    Antonio Herrera

    2015-01-01

    Full Text Available More than twenty years ago, hydroxyapatite (HA, calcium phosphate ceramics, was introduced as a coating for cementless hip prostheses. The choice of this ceramic is due to its composition being similar to organic apatite bone crystals. This ceramic is biocompatible, bioactive, and osteoconductive. These qualities facilitate the primary stability and osseointegration of implants. Our surgical experience includes the implantation of more than 4,000 cementless hydroxyapatite coated hip prostheses since 1990. The models implanted are coated with HA in the acetabulum and in the metaphyseal area of the stem. The results corresponding to survival and stability of implants were very satisfactory in the long-term. From our experience, HA-coated hip implants are a reliable alternative which can achieve long term survival, provided that certain requirements are met: good design selection, sound choice of bearing surfaces based on patient life expectancy, meticulous surgical technique, and indications based on adequate bone quality.

  5. Extremely high fracture rate of a modular acetabular component with a sandwich polyethylene ceramic insertion for THA: a preliminary report.

    Science.gov (United States)

    Kircher, Jörn; Bader, Rainer; Schroeder, Bettina; Mittelmeier, Wolfram

    2009-09-01

    Improvements of ceramic components and design changes have reduced failure rates over the past 30 years in total hip arthroplasty. We present a series of n = 11 cases with ceramic failure out of n = 113 implantations, from which n = 66 were ceramic-on-ceramic (n = 50 with ceramic insert with sandwich in polyethylene and n = 16 with directly fixed ceramic inlay) and n = 47 ceramic on polyethylene bearings, between 1999 and 2001 after introduction of a new implantation system to the market. The overall fracture rate of ceramic for the whole series (n = 113) was 9.7%. For the combination ceramic head with UHMW-PE (n = 47) the fracture rate was 2.1%. For the combination ceramic with ceramic (n = 66) the fracture rate was 15.2%. For the combination ceramic with ceramic sandwich in PE (n = 50) the failure rate was 18%. Only three patients experienced a trauma. Demography of patients (age, gender, body weight and BMI) was not statistically different between patients with failed ceramics and the rest of the patients making patient-specific risk factors unlikely to be an explanation for the failures. Retrospective X-ray analysis of the cup positioning did not show significant difference between failed and non-failed implants in terms of mean cup inclination and version making also operation-specific factors unlikely to be the only reason of this high failure rate. Therefore, manufacturer-specific factors such as design features may have contributed to this high failure rate. Further analysis of the whole series with biomechanical testing of the retrieved material needs to be performed. PMID:18568354

  6. Cementless isoelastic RM total hip prosthesis1

    OpenAIRE

    Bombelli, Renato; Mathys, Robert

    1982-01-01

    Some surgeons are beginning to doubt the reliability of bone cement in joint replacements. In 1967 Robert Mathys conceived the idea of an isoelastic prosthesis made of plastic, which would anchor into the bone without cement. He developed the idea by extensive tests in animals and, in 1973, the first human RM cementless hip prosthesis was inserted by E Morscher. In this paper the concept of the cementless isoelastic prosthesis is developed by Robery Mathys, and Professor Bombelli records his ...

  7. Three-fin acetabular prosthesis for superior acetabular bone defects: a three-dimensional finite element analysis

    Institute of Scientific and Technical Information of China (English)

    LIU Yu-zeng; HAI Yong; ZHAO Hui

    2012-01-01

    Background Given that three-dimensional finite element models have been successfully used to analyze biomechanics in orthopedics-related research,this study aimed to establish a finite element model of the pelvic bone and three-fin acetabular component and evaluate biomechanical changes in this model after implantation of a three-fin acetabular prosthesis in a superior segmental bone defect of the acetabulum.Methods In this study,three-dimensional finite element models of the pelvic bone and three-fin acetabular component were first established.The prosthesis model was characterized by three different conformational fins to facilitate and optimize the prosthetic design.The spongy and cortical bones were evaluated using a different modulus of elasticity in this established model.Results The maximum and minimum von Mises stresses on the fins of the acetabular component were 15.2 and 0.74,respectively.The maximum and minimum micromotion between the three-fin acetabular component and the acetabulum bone interface were 27 and 13 μm,respectively.A high primary stability and implied better clinical outcome were revealed.Conclusion Finite element analysis may be an optimal strategy for biomechanics-related research of prosthetic design for segmental acetabular bone defects.

  8. Accuracy of the modified Hardinge approach in acetabular positioning

    Science.gov (United States)

    Goyal, Prateek; Lau, Adrian; McCalden, Richard; Teeter, Matthew G.; Howard, James L.; Lanting, Brent A.

    2016-01-01

    Background The surgical approach chosen for total hip arthroplasty (THA) may affect the positioning of the acetabular component. The purpose of this study was to examine the accuracy in orienting the acetabular component using the modified Hardinge approach. Methods We used our institutional arthroplasty database to identify patients with primary, press-fit, hemispherical acetabular components of a metal-on-polyethylene THA performed between 2003 and 2011. Patients with radiographs obtained 1–3 years after the index procedure were included for measurement of anteversion and inclination angles. Acceptable values of anteversion and abduction angles were defined as 15° ± 10° and 40° ± 10°, respectively. Results We identified 1241 patients from the database, and the modified Hardinge approach was used in 1010 of the patients included in our analysis. The acetabular component was anteverted in the acceptable zone in 54.1% of patients. The abduction angle was within the defined range in 79.2% of patients. Combined anteversion and abduction angles within the defined zone were present in 43.6% of patients. Conclusion Consistent with studies examining accuracy from other approaches, our study reveals that the modified Hardinge approach was only moderately accurate in positioning the acetabular component in the acceptable zone. PMID:27240130

  9. Peri-acetabular bone mineral density in total hip replacement

    OpenAIRE

    Gauthier, L.(University of Illinois at Chicago (UIC), Chicago, USA); Dinh, L.; Beaulé, P. E.

    2013-01-01

    Objectives To quantify and compare peri-acetabular bone mineral density (BMD) between a monoblock acetabular component using a metal-on-metal (MoM) bearing and a modular titanium shell with a polyethylene (PE) insert. The secondary outcome was to measure patient-reported clinical function. Methods A total of 50 patients (25 per group) were randomised to MoM or metal-on-polyethlene (MoP). There were 27 women (11 MoM) and 23 men (14 MoM) with a mean age of 61.6 years (47.7 to 73.2). Measurement...

  10. Treatment of Hip Dysplasia in a Dog after a Failed Triple Pelvic Osteotomy with a Zurich Cementless Total Hip Replacement

    Directory of Open Access Journals (Sweden)

    SY Heo and H.B Lee*

    2013-07-01

    Full Text Available An Alaskan Malamute (2-year-old, castrated male, 41kg was referred with bilateral hind limb lameness. The dog had a history of a bilateral triple pelvic osteotomy (TPO to correct hip dysplasia one year previously, a surgery that was unsuccessful. On physical examination, pain and crepitus were noted in both hip joints. There was hip joint subluxation and mild degenerative changes bilaterally seen by radiograph. A Zurich cementless total hip replacement (ZCTHR was planned for the right hind limb. After a craniolateral approach, an acetabular cup and a cementless femoral stem were implanted. The femoral head was placed in the femoral stem, and the prosthetic joint was then reduced. At a 9 month postoperative checkup, there was no pain on palpation or manipulation of the right pelvic limb, and the range of motion was within normal limits. On radiological examination, there was no implant loosening. The ZCTHR can thus be applied in a failed TPO patient as a revision surgery.

  11. Comparison of acetabular reamings during hip resurfacing versus uncemented total hip arthroplasty.

    LENUS (Irish Health Repository)

    Brennan, S A

    2009-04-01

    PURPOSE: To compare the quantity of bone removed from the acetabulum during resurfacing hip arthroplasty versus uncemented total hip arthroplasty (THA). METHODS: 62 consecutive patients with osteoarthritis of the hip were prospectively studied. 24 men and 7 women aged 40 to 86 (mean, 59) years underwent Birmingham hip resurfacing. 13 men and 18 women aged 34 to 88 (mean, 61) years underwent uncemented THA using the trident acetabular cup. Obese elderly women at risk of femoral neck fracture and patients with large subchondral pseudocysts or a history of avascular necrosis of the femoral head were assigned to uncemented THA. Acetabular reamings were collected; marginal osteophytes were not included. The reamings were dehydrated, defatted, and weighed. RESULTS: The mean weight of acetabular reamings was not significantly different between patients undergoing hip resurfacing and uncemented THA (p=0.57). CONCLUSION: In hip resurfacing, the use of an appropriately small femoral component avoids oversizing the acetabular component and removal of excessive bone stock.

  12. Management of acetabular fractures: challenging work

    Institute of Scientific and Technical Information of China (English)

    CHEN Zheng-rong; YANG Yi

    2006-01-01

    @@ Acetabular fractures are complex and special intraarticular fractures. For most orthopaedic surgeons management of acetabular fractures is hard and challenging because the fractures are the results of high-energy trauma, and usually accompany with severe associated injuries. In addition, these fractures are uncommon except in a few trauma centers. The number of cases a surgeon can encounter is scarce.

  13. Relationship between Wiberg's lateral center edge angle, Lequesne's acetabular index, and medial acetabular bone stock

    International Nuclear Information System (INIS)

    Knowledge of acetabular anatomy is crucial for cup positioning in total hip replacement. Medial wall thickness of the acetabulum is known to correlate with the degree of developmental dysplasia of the hip (DDH). No data exist about the relationship of routinely used radiographic parameters such as Wiberg's lateral center edge angle (LCE-angle) or Lequesne's acetabular index (AI) with thickness of the medial acetabular wall in the general population. The aim of our study was to clarify the relationship between LCE, AI, and thickness of the medial acetabular wall. Measurements on plain radiographs (LCE and AI) and axial CT scans (quadrilateral plate acetabular distance QPAD) of 1,201 individuals (2,402 hips) were obtained using a PACS imaging program and statistical analyses were performed. The mean thickness of the medial acetabulum bone stock (QPAD) was 1.08 mm (95% CI: 1.05-1.10) with a range of 0.1 to 8.8 mm. For pathological values of either the LCE (12 ) the medial acetabular wall showed to be thicker than in radiological normal hips. The overall correlation between coxometric indices and medial acetabular was weak for LCE (r =-0.21. 95% CI [-0.25, -0.17]) and moderate for AI (r = 0.37, [0.33, 0.41]). We did not find a linear relationship between Wiberg's lateral center edge angle, Lequesne's acetabular index and medial acetabular bone stock in radiological normal hips but medial acetabular wall thickness increases with dysplastic indices. (orig.)

  14. Acetabular bone density and metal ions after metal-on-metal versus metal-on-polyethylene total hip arthroplasty; short-term results

    NARCIS (Netherlands)

    Zijlstra, Wierd P.; van der Veen, Hugo C.; van den Akker-Scheek, Inge; Zee, Mark J. M.; Bulstra, Sjoerd K.; van Raay, Jos J. A. M.

    2014-01-01

    Information on periprosthetic acetabular bone density is lacking for metal-on-metal total hip arthroplasties. These bearings use cobalt-chromium instead of titanium acetabular components, which could lead to stress shielding and hence periprosthetic bone loss. Cobalt and chromium ions have detriment

  15. An Unusual Combination of Acetabular and Pelvic Fracture: Is This a New Subtype of Acetabular Fracture?

    Directory of Open Access Journals (Sweden)

    Reza Tavakoli Darestani

    2013-01-01

    Full Text Available Introduction: Acetabular fractures are a common problem among young males. An acetabular fracture with disruption of the joint surface, if untreated, will rapidly lead to post-traumatic osteoarthritis. Proper reduction and internal fixation depend on accurate classification and the quality of imaging.Case Presentation: We present an unusual form of acetabular fracture, which is not included in the conventional classification (Judet and Letournel ; this occurred in a middle-aged male who was operatively treated without any complications. In this case due to posterior extension of the fracture into the SI joint and concomitant anterior column fracture in the area above the acetabular dome, no portion of the acetabular anterior surface remained connected to the innominate bone.Conclusions: We recognized this type of fracture and treated it similarly to both column fractures. We recommend that the classification of acetabular fractures be modified to include this type of fracture.

  16. Oxidation and other property changes of retrieved sequentially annealed UHMWPE acetabular and tibial bearings.

    Science.gov (United States)

    Reinitz, Steven D; Currier, Barbara H; Van Citters, Douglas W; Levine, Rayna A; Collier, John P

    2015-04-01

    This investigation analyzed retrieved sequentially crosslinked and annealed (SXL) ultra-high molecular weight polyethylene bearings to determine whether the material is chemically stable in vivo. A series of retrieved tibial and acetabular components were analyzed for changes in ketone oxidation, crosslink density, and free radical concentration. Oxidation was observed to increase with in vivo duration, and the rate of oxidation in tibial inserts was significantly greater than in acetabular liners. SXL acetabular bearings oxidized at a rate comparable to gamma-sterilized liners, while SXL tibial inserts oxidized at a significantly faster rate than their gamma-sterilized counterparts. A significant decrease in crosslink density with increased mean ketone oxidation index was observed, suggesting that in vivo oxidation may be causing material degradation. Furthermore, a subsurface whitened damage region was also found in a subset of the bearings, indicating the possibility of a clinically relevant decrease in mechanical properties of these components. PMID:24956572

  17. Total hip arthroplasty in patients with avascular necrosis of the hip. Follow-up observations on cementless and cemented operations.

    Science.gov (United States)

    Katz, R L; Bourne, R B; Rorabeck, C H; McGee, H

    1992-08-01

    Thirty-one patients with avascular necrosis of the hip were treated by 34 total hip arthroplasties (THAs). All patients were observed prospectively with a minimum two-year follow-up evaluation (average, 46 months; range, 24-84 months). Twenty had cemented arthroplasties using contemporary cementing techniques. This included insertion of a medullary plug, cleansing of the canal with a medullary brush, pulsatile lavage irrigation, and insertion of the cement with a cement gun. In 14 hips, a cementless prosthesis was used. Patients were rated using a modified Harris hip score. Sequential postoperative roentgenograms were analyzed in each patient. The overall Harris hip score ratings were 88 in the cemented and 84 in the noncemented groups. Mechanical failure with loosening of the femoral component occurred in one patient who developed deep sepsis. Significant thigh pain occurred in four patients in the noncemented group. Previous studies in the literature have generally reported unfavorable results in patients with avascular necrosis of the hip treated with THA. Using cementless and cemented fixation with contemporary cementing techniques, improved results can be expected. A high incidence of thigh pain (29%) in the cementless group remains a problem. PMID:1499201

  18. Osteoarthritis of the hip and acetabular dysplasia.

    OpenAIRE

    Croft, P.; Cooper, C.; Wickham, C; Coggon, D

    1991-01-01

    The relation between acetabular dysplasia and osteoarthritis of the hip was examined in a series of 1516 pelvic radiographs taken for non-skeletal indications. Osteoarthritis was assessed by measuring joint space, and dysplasia by the centre-edge angle and acetabular depth. In contrast with previous studies of patients with symptomatic osteoarthritis of the hip, no evidence that dysplasia predisposes to osteoarthritis was found. Possible reasons for the discrepancy are discussed. It was concl...

  19. Short term results of cementless total hip arthroplasty in sicklers

    Directory of Open Access Journals (Sweden)

    Yash Gulati

    2015-01-01

    Conclusion: THA in sicklers involves considerable challenge for the orthopedic surgeon. Management requires a multidisciplinary approach involving the anesthetist, hematologist and the orthopedic surgeon. Contrary to previous reports, THA in sicklers now has a predictable outcome especially with the use of cementless implants.

  20. Influence of clinical and radiological variables on the extent and distribution of periprosthetic osteolysis in total hip arthroplasty with a hydroxyapatite-coated multiple-hole acetabular component: a magnetic resonance imaging study.

    Science.gov (United States)

    Pérez-Coto, Iván; Hernández-Vaquero, Daniel; Suárez-Vázquez, Abelardo; Sandoval-García, Manuel Ángel; Escandon-Rodriguez, Ana

    2014-10-01

    Polyethylene wear-induced osteolysis constitutes the most severe long-term complication of total hip arthroplasties (THA). Our aim was to assess through MRI the severity and growth pattern of osteolysis, as well as the influence clinical-radiographic variables exert. We analyzed 75 THA with an average evolution time of 13.67years. The implant was a titanium alloy, non-cemented, multiple-hole model with hydroxyapatite coating. Osteolysis was found with a peripheral pattern in 48 and a central pattern in 6; in 52 cases it was continuous, and in 4, isolated. Out of 118 screws, 20 exhibited lysis. There was a proportional correlation between osteolysis severity and wear rate with age, physical activity and acetabular abduction, as well as an association between said variables and peripheral and continuous patterns. PMID:24986509

  1. Surgical treatment for complicated acetabular fractures

    Institute of Scientific and Technical Information of China (English)

    Ning An; Yang Yanmin

    2004-01-01

    Objective: To sum up the surgical approaches and clinical outcome of complicated acetabular fractures. Methods: 17 patients with complicated acetabular fractures (including 4 cases of transverse with posterior wall fractures, 7 cases of posterior column and wall fractures, 4 cases of anterior and posterior columns fractures, 1 cases of T-type fracture and 1 cases of anterior column with posterior hemitransverse fractures) underwent open reduction and internal fixation with screws and plates by Kocher-Langenbeck (8 cases), ilio-inguinal (2 cases), extended iliofemoral (4 cases) or ilio-inguinal combined with K-L approaches (3 cases). Results: 12 patients with anatomical reduction, 4 patients with satisfactory reduction and 1 patient with non-satisfactory reduction. 15 out of 17 cases were followed up for 6 months to 5 years, and the excellent and good rate was 70.5%. Conclusion: Surgical treatment for complicated acetabular fractures can get a satisfactory reduction and a good clinical outcome.

  2. Osteopathic diagnosis of an acetabular injury.

    Science.gov (United States)

    Morthland, Tim; Cote, Nicholas S; Humphrey, Jon; Fulk, Doug

    2010-05-01

    Physical findings demarking pathologic somatovisceral reflex activity and fascial strain patterns may lead the osteopathic physician to diagnoses that are masked within the initial presentation of a patient. The authors present a case report that demonstrates the use of osteopathic principles in the diagnosis of a chronic acetabular fracture and acetabular labral tear in a 19-year-old man. The injuries resulted from a posterior hip dislocation sustained during a basketball game more than 1 year before presentation. Osteopathic manipulative treatment and diagnostic techniques also relieved the patient's persistent thoracic pain, nausea, and vomiting. Subsequent orthopedic repair had the potential to avert or delay degenerative hip disease in the patient. PMID:20538751

  3. PRIMARY CEMENTLESS TOTAL HIP ARTHROPLASTY IN ANKYLOSING SPONDYLITIS

    OpenAIRE

    Nageshwara Rao; Ravikumar

    2015-01-01

    INTRODUCTION Ankylosing Spondylitis (AS), family of Spondyloarthritides (SpAs), is a chronic inflammatory disease affecting the axial skeleton, the entheses and occasionally the peripheral joints. The shoulders and hips are considered axial joints and involvement occurs in up to 50% of patients and is more common than involvement of the more distal joints. Aim of our study is to evaluate outcome of Cementless Total Hip Arthroplasty (THA) in ankylosing spondylitis. MAT...

  4. Immediate Cementless Hemiarthroplasty for Severe Destructive Glenohumeral Tuberculous Arthritis

    OpenAIRE

    Suriya Luenam; Arkaphat Kosiyatrakul

    2013-01-01

    The glenohumeral joint tuberculosis (TB) is rare as compared with other joints. Plaster immobilization, arthrodesis, and resection arthroplasty have been proposed as the additional treatments with anti-TB medications in severe destructive arthritis. To our knowledge, however, the surgical treatment with shoulder arthroplasty has never been reported. We present two cases of active TB with unsalvageable glenohumeral joint. The cementless hemishoulder arthroplasties were performed immediately fo...

  5. PRIMARY CEMENTLESS TOTAL HIP ARTHROPLASTY IN ANKYLOSING SPONDYLITIS

    Directory of Open Access Journals (Sweden)

    Nageshwara Rao

    2015-12-01

    Full Text Available INTRODUCTION Ankylosing Spondylitis (AS, family of Spondyloarthritides (SpAs, is a chronic inflammatory disease affecting the axial skeleton, the entheses and occasionally the peripheral joints. The shoulders and hips are considered axial joints and involvement occurs in up to 50% of patients and is more common than involvement of the more distal joints. Aim of our study is to evaluate outcome of Cementless Total Hip Arthroplasty (THA in ankylosing spondylitis. MATERIALS AND METHODS We prospectively and retrospectively reviewed 27 hips in 20 patients who underwent cementless THA between 2007-2013. Mean age of patient was 31.5 years. We analysed demographic data, preoperative deformity, Harris Hip Score, ambulatory status, need for walking aids. RESULTS All patients experienced significant improvement in function, range of motion, posture and ambulation. Postoperative Harris Hip Score improved from 18.95 to 89.35; 90% are completely pain free, 5% have occasional discomfort and 5% have mild-to-moderate pain. CONCLUSION Cementless THA for deformed hips in young patients with AS is worthwhile surgical intervention, as it increases the mobility of the patient, improves the ability to sit comfortably, decrases the morbidity of the disease. However, the technically demanding nature of the procedure should not be underestimated.

  6. An unusual mode of failure of a tripolar constrained acetabular liner: a case report.

    LENUS (Irish Health Repository)

    Banks, Louisa N

    2012-02-01

    Dislocation after primary total hip arthroplasty (THA) is the most commonly encountered complication and is unpleasant for both the patient and the surgeon. Constrained acetabular components can be used to treat or prevent instability after primary total hip arthroplasty. We present the case of a 42-year-old female with a BMI of 41. At 18 months post-primary THA the patient underwent further revision hip surgery after numerous (more than 20) dislocations. She had a tripolar Trident acetabular cup (Stryker-Howmedica-Osteonics, Rutherford, New Jersey) inserted. Shortly afterwards the unusual mode of failure of the constrained acetabular liner was noted from radiographs in that the inner liner had dissociated from the outer. The reinforcing ring remained intact and in place. We believe that the patient\\'s weight, combined with poor abductor musculature caused excessive demand on the device leading to failure at this interface when the patient flexed forward. Constrained acetabular components are useful implants to treat instability but have been shown to have up to 42% long-term failure rates with problems such as dissociated inserts, dissociated constraining rings and dissociated femoral rings being sited. Sometimes they may be the only option left in difficult cases such as illustrated here, but still unfortunately have the capacity to fail in unusual ways.

  7. CT evaluation of acetabular dysplasta in adults.

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To evaluate methods of measurement by CT and their clinical significance for acetabular dysplasia(AD) in adults. Methods: CT imaging was examined and measured in 33 adult patients with AD, compared with the normal control group of 210 adults. Results: This study showed the results of AD patients

  8. Deformation process and interaction of acetabular cup

    Czech Academy of Sciences Publication Activity Database

    Jíra, J.; Jírová, Jitka; Micka, Michal

    Dusseldorf, Německo: VDI Verlag GmbH, 2001, s. 197-202. ISBN 3-18-091599-4. [GESA-Symposium 2001. Chemnitz (DE), 17.05.2001-18.05.2001] R&D Projects: GA ČR GA103/00/0831 Keywords : acetabular cup migration, computation modelling,straingauge measurement. Subject RIV: FI - Traumatology, Orthopedics

  9. Thin-Walled Cross-Linked Acetabular Liners Need Not Exhibit Reduced Locking Strength.

    Science.gov (United States)

    Murtha, Andrew S; Roy, Marcel E; Whiteside, Leo A; Tilden, David S; Schmitt, Krystal L

    2015-08-01

    Use of larger diameter femoral heads has emerged as a promising strategy to reduce the risk of dislocation after total hip arthroplasty, but thinning the walls of cross-linked ultra-high-molecular-weight polyethylene (UHMWPE) acetabular liners to accommodate these larger heads may compromise the locking mechanism of the liner. The purpose of this study was to test the mechanical integrity of the locking mechanism in cross-linked and re-melted UHMWPE acetabular components with reduced wall thickness. The locking mechanism of cross-linked (100 kGy/re-melted) acetabular liners in sizes 50/28, 50/36, and 52/36 mm of 1 design was evaluated by lever-out tests and torsion tests. Torsion tests were performed at 2 angles to isolate the liner's locking tabs independent of the contribution of its central post. Lever-out testing demonstrated nominally reduced failure strength in 50/36-mm liners (13.3 N · m) compared with 50/28-mm liners (12.3 N · m; P=.0502), whereas the lever-out strength of 52/36-mm liners was 12.2±0.94 N · m. Failure torques were similar between 50/28- and 50/36-mm liners at 45° and 90°, but the failure torque of size 52/36-mm liners was significantly higher at each angle. The use of larger diameter femoral heads does not compromise the locking mechanism of thinned MicroSeal (Signal Medical Corp, Marysville, Michigan) acetabular liners. Use of a cross-linked UHMWPE acetabular liner, with a locking mechanism that is not compromised when the liner is thinned to a thickness of at least 2.86 mm, appears to be a biomechanically sound construct when articulated with large diameter femoral heads. PMID:26270761

  10. Sciatic Nerve Injury Associated with Acetabular Fractures

    OpenAIRE

    Issack, Paul S; Helfet, David L

    2008-01-01

    Sciatic nerve injuries associated with acetabular fractures may be a result of the initial trauma or injury at the time of surgical reconstruction. Patients may present with a broad range of symptoms ranging from radiculopathy to foot drop. There are several posttraumatic, perioperative, and postoperative causes for sciatic nerve palsy including fracture–dislocation of the hip joint, excessive tension or inappropriate placement of retractors, instrument- or implant-related complications, hete...

  11. Surgical treatment for complex acetabular fractures

    Institute of Scientific and Technical Information of China (English)

    LIU Qiang; WU Dou; LI Ping; HAN Shu-feng

    2006-01-01

    Objective: To explore the effect of surgical treatment on complex acetabular fractures.Methods: The data of 46 patients (38 males and 8 females, aged 16-75 years, mean = 38. 5 years ) with complex acetabular fractures, who were admitted to our hospital from January 1998 to December 2005, were analyzed retrospectively in this study. According to Letournel rules, posterior wall and posterior column fractures were found in 11 patients, transverse and posterior wall fractures in 13, T-type fracture in 4, both columns fracture in 10, and anterior column and posterior transverse fracture in 8. The choice of surgical approach was based on the individual fractures, which included ilioinguinal approach in 5 patients, Kocher-Langenbech approach in 7, combined approach in 26, and extended iliofemoral approach in 8.Results: All the patients were followed up for 3.5 years averagely. The clinical outcomes were analyzed with Harris hip score and radiography. In 36 patients (78.3%), the surgical procedure was successful (Harris hip score > 80 points). The rate of excellent and good was about 86 %.Conclusions: The keys to increase the effectiveness of surgical treatment on acetabular fractures are correct preoperative classification of factures and choices of appropriate surgical approach and time.

  12. The early-term clinical efficacy of titanium trabecular metal acetabular components produced by E-beam technology in total hip arthroplasty%3D打印钛合金骨小梁金属臼杯全髋关节置换术的短期疗效

    Institute of Scientific and Technical Information of China (English)

    程文俊; 勘武生; 郑琼; 王俊文; 徐海军; 肖志宏

    2014-01-01

    Objective To explore the early-term efficacy of porous titanium trabecular metal acetabular (TTM) compo-nents produced by E-beam technology in total hip arthroplasty(THA). Methods From May 2012 to JUN 2013, nineteen primary THA patients (20 hips) were devided into observation group of porous TTM acetabular prosthesis produced by E-beam technology and control group of Pinnacle acetabular prosthesis. TTM group had nine patients (10 hips), including 7 males and 2 females, with the mean age of 61.0 years. Pinnacle group had ten patients (10 hips), including 6 males and 4 females, with the mean age of 58.6 years. The patients were followed up at the 6,12,24 weeks after operation. X-rays were taken at the follow-ups. Acetabular compo-nent stability and osseointegration were assessed through radiograph. Harris scores system,SF-36 Heath Survey Questionnaire and WOMAC Osteoarthritis index were recorded before and after operation to evaluate clinical effects of surgery. Results In TTM group, the Harris score improved from 48.2 ± 5.5 preoperatively to 89.5 ± 4.0 postoperatively, SF-36 scores from 329.1 ± 86.7 to 763.8 ± 15.1, and WOMAC index from 18.8 ± 11.0 to 1.3 ± 0.9. No cases suffered aseptic loosening and migration. After 24 weeks, There was no significant difference regarding Harris scores system,SF-36 Heath Survey Questionnaire and WOMAC Os-teoarthritis index between two groups. In TTM group, two hips had a radiolucent line postoperatively, which occurred in 2 and 3 zone. The lines were disappeared 24 weeks later. Conclusion In THA, the initial stability of TTM produced by E-beam tech-nology was fine, which can facilitate bone ingrowth in early stage. However, the long-term follow-up effect still needs to be con-firmed.%目的:评估3D打印钛合金骨小梁金属(titanium trabecular metal,TTM)臼杯在初次全髋关节置换术(total hip arthroplasty, THA)中应用的短期疗效。方法2012年5月至2013年6月,选取19例(20髋)进行初

  13. Acetabular paralabral cyst: an uncommon cause of sciatica

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, P.M.; Sanders, T.G. [Department of Radiology, Wilford Hall Medical Center, 2200 Bergquist Drive, Ste. 1, Lackland AFB, TX 78236 (United States); Matchette, M.W. [University of Texas Medical School, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900 (United States); Parsons, T.W. [Department of Orthopedic Surgery, Wilford Hall Medical Center, 2200 Bergquist Drive, Ste. 1, Lackland AFB, TX 78236 (United States)

    2003-02-01

    The association between tears of the acetabular labrum and paralabral cysts has been well documented, and magnetic resonance imaging (MRI) has been shown to be the most accurate noninvasive method of depicting not only the normal anatomic structures of the hip, but also the common pathologic processes such as labral tears and paralabral cysts. We present the case of an acetabular paralabral cyst that resulted in clinically symptomatic compression of the sciatic nerve. (orig.)

  14. Relationship between sacral pelvic incidence and acetabular orientation.

    Science.gov (United States)

    Legaye, Jean; Duval-Beaupere, Ginette; Barrau, Andre; Boulay, Christophe; Hecquet, Jerome; Montigny, Jean-Pierre; Tardieu, Christine

    2011-01-01

    The importance of the sacral pelvic incidence (SPI) in relation to individual variations of sagittal spinal curvature has become well-recognised. We attempted to determine the relationship between SPI and acetabular orientation. The three-dimensional coordinates of 47 homologous points were observed on 51 adult anatomical pelvises (26 female and 25 male). The reference vertical plane was Lewinnek's anterior pelvic plane. 10 angular parameters and 11 linear parameters were defined and calculated. These were expressed both in absolute value (in millimetres) and in "acetabular unit" (relative to the mean value of the right and left acetabular rays). Mean values of the parameters were calculated for all pelvises and according to gender. There were two dominant parameters: the "sacral slope" and the "V pubic angle". "Acetabular tilting" was primarily dependent on the "sacral slope" and its intermediary on the "SPI", while "acetabular anteversion" dependent on the "V pubic angle" via the "angle of prow". It is recommended that positioning of the acetabular cup in total hip arthroplasty relates to anatomical parameters, and to the global sagittal balance of the pelvi-spinal unit. PMID:21279971

  15. Outcomes of a Newer-Generation Cementless Total Knee Arthroplasty Design.

    Science.gov (United States)

    Harwin, Steven F; Elmallah, Randa K; Jauregui, Julio J; Cherian, Jeffrey J; Mont, Michael A

    2015-10-01

    Newer-generation cementless total knee arthroplasties (TKAs) aim to improve durability, function, and longevity. In a large series of cementless TKAs at a mean 4-year follow-up, the authors evaluated (1) survivorship, (2) range of motion, (3) patient-reported outcomes, and (4) complications. Mean age was 66 years (range, 34-88 years) and mean body mass index was 32.5 kg/m(2) (range, 20-54 kg/m(2)). Aseptic and septic implant survivorships were 99.6% and 99.5%, respectively. Mean extension, flexion, and Knee Society scores improved significantly. There were 3 septic failures. Aseptic failures included 3 aseptic loosenings, 1 polyethylene revision, and 1 revision to a cemented patella. This study showed excellent clinical and patient-reported outcomes of cementless TKA. PMID:26488775

  16. THE HIGH VOLUME REUSE OF HYBRID BIOMASS ASH AS A PRIMARY BINDER IN CEMENTLESS MORTAR BLOCK

    Directory of Open Access Journals (Sweden)

    Cheah Chee Ban

    2014-01-01

    Full Text Available High Calcium Wood Ash (HCWA and Pulverised Fuel Ash (PFA are by-products from the wood biomass and coal energy production which are produced in large quantity with combined annual production of 500 million tonnes. This poses a serious problem for disposal of the waste material especially at places where land is scarce. The prescribed study was aimed to examine the mineralogical phases and their respective amount present in the industrial wastes which governs the hydration mechanism towards self-sustained solidification of the ashes when used in combination. Besides, the influence of various forming pressure and hydrothermal treatment temperature on mechanical strength performance of HCWA-PFA cementless mortar blocks was also examined. In the study, the mechanical strength of the HCWA-PFA cementless mortar block produced using various forming pressure and hydrothermal treatment temperature was assessed in terms of compressive strength and dynamic modulus. The results of the study are indicative that HCWA is rich in calcium oxide and potassium oxide content. This enables the hybridization of HCWA with the amorphous silica and alumina rich PFA to form a solid geopolymer binder matrix for fabrication of cementless mortar block. Throughout the study, dimensionally and mechanically stable HCWA-PFA geopolymer mortar blocks were successfully produced by press forming and hydrothermal treatment method. Based on statistical analysis, the hydrothermal treatment temperature has a statistically insignificant effect on the mechanical strength of the HCWA-PFA cementless mortar blocks. The dominant factor which governs the mechanical strength of the HCWA-PFA cementless mortar blocks was found to be the hydraulic forming pressure. Moreover, it was found that hybridized HCWA-PFA can be recycled as the sole binder for fabrication of cementless concrete block which is a useful construction material.

  17. Results of cementless hip arthroplasty; Ergebnisse zementfreier Hueftendoprothetik

    Energy Technology Data Exchange (ETDEWEB)

    Gruebl, A. [Medizinische Universitaet Wien, Klinik fuer Orthopaedie, Wien (Austria)

    2006-09-15

    Hip arthroplasty is performed nowadays according to the needs of the patients irrespective of their age. Tapered rectangular stems for cementless fixation are chosen in most cases in central Europe. They provide primary stability by press-fit implantation into a precisely rasped osseous bed and secondary stability by bone ingrowth into the highly biocompatible titanium alloy with a microrough surface. The 10-year survival of such devices is 92%. Typical radiographic patterns include cortical atrophy and radiolucent lines in Gruen zones 1 and 7. They are due to stress shielding with these distally fixed implants. The number one reason for revision is polyethylene wear and subsequent osteolysis. Metal-on-metal and ceramic-on-ceramic bearings show less wear but osteolysis continues to be a problem. (orig.) [German] Hueftendoprothesen werden implantiert, wenn der Patient sie, unabhaengig vom Alter, braucht. Mehrheitlich kommen rechteckige Geradschaefte zementfrei zur Anwendung. Sie gewaehrleisten eine primaer stabile Verankerung durch Press-Fitt-Implantation in ein praezise geraspeltes knoechernes Bett und sekundaere Stabilisierung durch Anwachsen von Knochen auf der mikrorauen Oberflaeche der biokompatiblen Titanlegierung. Die Zehnjahresueberlebensraten fuer solche Prothesen betraegt 92%. Typische Roentgenzeichen sind proximale kortikale Atrophie und Saeume in den Gruen-Zonen 1 und 7, die aber kein Zeichen der Lockerung darstellen. Der haeufigste Grund fuer Revisionsoperationen ist der Polyethylenabrieb und daraus resultierende Osteolysen. Moderne Gleitpaarungen wie Metall/Metall und Keramik/Keramik haben deutlich weniger Abrieb, das Problem der Osteolysen ist aber nicht geloest. (orig.)

  18. The dimensional accuracy of preparation of femoral cavity in cementless total hip arthroplasty

    Institute of Scientific and Technical Information of China (English)

    吴立东; HAHNEH.J.; HASSENPFLUGJ.

    2004-01-01

    Objective: To observe the accuracy of femoral preparation and the position of the cementless prosthesis in femoral cavity, and to compare the results between the computer-assisted surgical group (CASPAR) and the conventional group. Methods: Ten femoral components were implanted either manually or by CASPAR in cadaver femurs. The specimens were cut to 3mm thick slices. Microradiograms of every slice were sent to a computer for analysis with special software (IDL). The gaps and the medullary cavities between component and bone, the direct bone contact area of the implant surface, the gap width and the percentage of gap and bone contact area were measured in every slice. Results: In the proximal implant coated with HA of the CASPAR group, the average percentage of bone contact reached 93.2% (ranging from 87.6% to 99.7%); the average gap percentage was 2.9% (ranging from 0.3% to 7.8%); the maximum gap width was 0.81mm and the average gap width was only 0.20mm. While in the conventional group, the average percentage of bone contact reached 60.1% (ranging from 49.2% to 70.4%); the average gap percentage was 32.8% (ranging from 25.1% to 39.9%); the maximum gap width was 2.97mm and the average gap width was 0.77mm. The average gap around the implant in the CASPAR group was only 9% of that in the manual group; the maximum and average gap widths were only about 26% of those in the manual group. On the other hand, the CASPAR group showed 33% higher bone contact than the manual group. Conclusion: With the use of robotics-assisted system, significant progress can be achieved for femoral preparation in total hip arthroplasty.

  19. Intraoperative measurement of rotational stability of femoral components of total hip arthroplasty.

    Science.gov (United States)

    Harris, W H; Mulroy, R D; Maloney, W J; Burke, D W; Chandler, H P; Zalenski, E B

    1991-05-01

    High out-of-plane forces acting on the hip joint can produce important rotational micromotion of the femoral component. This micromotion at the prosthesis interface may be detrimental to the stability of the implant. In cementless femoral implants this could prevent bone ingrowth, and in the cemented component this could cause generation of particulate debris, lysis, and loosening. The introduction of the torque wrench micrometer for assessment of intraoperative femoral component stability can quantify the initial stability of primary cementless femoral components and critically evaluate the stability (at either the initial or revision arthroplasty) of both cemented and cementless femoral components. It allows the surgeon to produce a known torque in the direction and magnitude of the out-of-plane forces that load the hip in vivo. PMID:2019039

  20. Large head metal-on-metal cementless total hip arthroplasty versus 28mm metal-on-polyethylene cementless total hip arthroplasty: design of a randomized controlled trial

    OpenAIRE

    van Raaij Jos JAM; Bos Nanne; Zijlstra Wierd P

    2008-01-01

    Abstract Background Osteoarthritis of the hip is successfully treated by total hip arthroplasty with metal-on-polyethylene articulation. Polyethylene wear debris can however lead to osteolysis, aseptic loosening and failure of the implant. Large head metal-on-metal total hip arthroplasty may overcome polyethylene wear induced prosthetic failure, but can increase systemic cobalt and chromium ion concentrations. The objective of this study is to compare two cementless total hip arthroplasties: ...

  1. A biodegradable gentamicin-hydroxyapatite-coating for infection prophylaxis in cementless hip prostheses

    NARCIS (Netherlands)

    Neut, D.; Dijkstra, R. J. B.; Thompson, J. I.; Kavanagh, C.; van der Mei, H. C.; Busscher, H. J.

    2015-01-01

    A degradable, poly (lactic-co-glycolic acid) (PLGA), gentamicin-loaded prophylactic coating for hydroxyapatite (HA)-coated cementless hip prostheses is developed with similar antibacterial efficacy as offered by gentamicin-loaded cements for fixing traditional, cemented prostheses in bone. We descri

  2. Functional and radiographic evaluation and quality of life analysis after cementless total hip arthroplasty with ceramic bearings: minimum of 5 years follow-up

    Directory of Open Access Journals (Sweden)

    Rafael Borghi Mortat

    2013-12-01

    Full Text Available Objective: The aim of the study is to analyze and correlate functional and radiographic results and quality of life in patients undergoing cementless total hip arthroplasty with ceramic surface, performed at Hospital Servidor Publico de Sao Paulo from 2001 to 2006. Methods: We retrospectively analyzed 35 hips treated with cementless total hip arthroplasty with ceramic surfaces with a minimum follow-up of 5 years. Functional evaluation was based on the Harris Hip Score (HHS. Radiographic evaluation was based on the method proposed by Charles Engh for evaluation of femoral osseointegration and on DeLee and Charnley zones for acetabulum. Quality of life was assessed by SF-36 questionnaire. Results: The HHS presented excellent and good results in 91% of patients postoperatively (mean of 93.14 points HHS. As for radiographic evaluation, we found excellent results in 100% of evaluated hips (proven osseointegration. SF-36 scores were not compared to the control group for the following components: pain, vitality, mental health and social aspects. The difference between HHS pre and postoperatively had a statistically significant correlation with physical functioning of the SF-36. Conclusion: Total hip arthroplasty with ceramic surface is a treatment that enables functional improvement of the hip and increases quality of life of patients to levels close to those of people without joint diseases.

  3. Press fit shape femoral heads for acetabular reconstruction - 5 to 8 years results

    International Nuclear Information System (INIS)

    Filling of acetabular defects with allograft bone is a favourable method in revision-THR provided that primary stability and load bearing capability can be achieved. Since 1990 we perform structural allografting in the acetabular area using a special technique. Defects are prepared with hemispherical reamers (male) in order to obtain a smooth concave surface. Deep-frozen femoral heads are then prepared using female shapers of a diameter 0-4mm larger, thus obtaining a convex surface fitting precisely into the prepared bed. In ideal cases a press-fit can be obtained granting primary stability without additional implants, otherwise we secure the grafts against rotation with one or two traction screws in loading-direction. Implantation of the cup is performed like in primary THR, care is taken to place the implant exactly at the anatomically correct position. Weight bearing is performed as soon as after primary THR; due to the technique loads are distributed evenly over the entire contact area to host bone, pressing the graft firmly into its bed. From 1990 to 1993 this method has been used in 179 cases. 104 cases could be followed between 60 and 95 months (average 71,5 months). Mean age at operation was 66,5 years (39-87 vears). Defects were classified according to Gross as cavitary in 15, minor column in 50 and major column in 39 cases. 85x the cup has been cemented, 19x cementless. One uncemented and 7 cemented cups loosened, all within the first 2 years. 6 meanwhile have been revised a second time. Those usually were cases, where the cup was placed in a non-anatomical position and / or the graft was not secured against rotatory forces. In 17 cases we observed slight condensation of the grafts with consequent migration of the implants. Migration usually did not exceed 5mm and no other signs of implant loosening have been associated. Radiographs indicated a unifon-n pattern of rapid graft-incorporation. Remodelling seemed to be completed after the second year, from

  4. MR imaging findings of acetabular dysplasia in adults

    Energy Technology Data Exchange (ETDEWEB)

    James, Steven; Connell, David [The Royal National Orthopaedic Hospital, Radiology Department, London, Middlesex (United Kingdom); Miocevic, Miranda; Malara, Frank; Pike, Jonathan [Victoria House Hospital, Radiology Department, Melbourne (Australia); Young, David [Melbourne Orthopaedic Group, Orthopaedic Surgery, Melbourne (Australia)

    2006-06-15

    To evaluate the diagnostic accuracy of MR imaging in the identification of labral and articular cartilage lesions in patients with acetabular dysplasia. Pre-operative MR imaging was performed on 27 hips in 25 consecutive patients (16 males, 9 females, age range 19-52 years, mean age 31.2 years) with radiographic evidence of acetabular dysplasia (centre-edge angle of Wiberg <20 degrees). The average duration of symptoms was 16.2 months. Two musculoskeletal radiologists assessed MR images in consensus for the presence of abnormality involving the acetabular labrum and adjacent acetabular articular cartilage. A high resolution, non-arthrographic technique was used to assess the labrum and labral chondral transitional zone. Surgical correlation was obtained in all cases by a single surgeon experienced in hip arthroscopy and ten patients with normal hip MRI were included to provide a control group. The acetabular labra in the dysplastic hips demonstrated abnormal signal intensity, and had an elongated appearance when compared with the control group (mean length 10.9 mm vs 6.4 mm). Morphological appearances in the labra included surface irregularity, fissures and cleft formation. MR imaging correctly identified the severity of chondral abnormality in 24 of 27 hips (89%) when compared with arthroscopic findings. MR imaging demonstrates an elongated labrum, focal intra-substance signal change and irregularity and fissuring of the margins in patients with acetabular dysplasia. Abnormality is also identified at the labral chondral transitional zone, where fissuring, focal clefts, chondral deficiency and subchondral cyst formation may be apparent. A high-resolution, non-arthrographic technique can provide an accurate preoperative assessment and evaluate the presence of premature osteoarthritis. (orig.)

  5. Acetabular reconstruction with human and bovine freeze-dried bone grafts and a reinforcement device

    Directory of Open Access Journals (Sweden)

    Ricardo Rosito

    2008-01-01

    Full Text Available BACKGROUND: This is a cohort trial (1997-2005 of 49 patients submitted to an acetabular component revision of a total hip arthroplasty, using impacted human and bovine freeze-dried cancellous bone grafts (H&FDBG and a reinforcement device. OBJECTIVE: To compare clinical/radiographic graft incorporation capability between cancellous bone grafts. PATIENTS/METHODS: There were two groups: I (n=26 receiving human grafts and II (n=25 receiving bovine grafts. The average follow-up times were 55 and 49 months, respectively. Clinical analysis was based on the Merle d'Aubigné and Postel score, and the radiographic analysis involved an established score based on Conn's et al. criteria for radiographic bone incorporation. RESULTS: No clinical/radiographic differences were found between the groups and both showed an overall rate of 88.5% and 76% of graft incorporation (p=0.424. CONCLUSION: The results presented here are comparable to those in the literature with the use of deep-FG. Therefore, cancellous bone grafts can be safely and adequately used in acetabular component revision in total hip arthroplasty.

  6. Acetabular Reconstruction with Human and Bovine Freeze- Dried Bone Grafts and a Reinforcement Device

    Science.gov (United States)

    Rosito, Ricardo; Galia, Carlos Roberto; Macedo, Carlos Alberto Souza; Moreira, Luis Fernando; Quaresma, Lourdes Maria Araújo C.; Palma, Humberto Moreira

    2008-01-01

    BACKGROUND This is a cohort trial (1997–2005) of 49 patients submitted to an acetabular component revision of a total hip arthroplasty, using impacted human and bovine freeze-dried cancellous bone grafts (H&FDBG) and a reinforcement device. OBJECTIVE To compare clinical/radiographic graft incorporation capability between cancellous bone grafts. PATIENTS/METHODS There were two groups: I (n=26) receiving human grafts and II (n=25) receiving bovine grafts. The average follow-up times were 55 and 49 months, respectively. Clinical analysis was based on the Merle d’Aubigné and Postel score, and the radiographic analysis involved an established score based on Conn’s et al. criteria for radiographic bone incorporation. RESULTS No clinical/radiographic differences were found between the groups and both showed an overall rate of 88.5% and 76% of graft incorporation (p=0.424). CONCLUSION The results presented here are comparable to those in the literature with the use of deep-FG. Therefore, cancellous bone grafts can be safely and adequately used in acetabular component revision in total hip arthroplasty. PMID:18719763

  7. Comparison of postoperative curative effect and the possible survival rate of prosthesis following cemented and cementless total hip replacement%人工全髋关节置换骨水泥和无骨水泥假体术后疗效及假体可能的生存率比较

    Institute of Scientific and Technical Information of China (English)

    张勇; 杨彤涛; 周勇; 马保安

    2006-01-01

    ,假体都没有达到理想固定的效果.假体类型的选择并不影响假体的寿命,要根据患者的年龄及是否还要行翻修术来决定假体类型;骨溶解与患者年龄、性别、假体类型无关.%BACKGROUND: Patients who suffered total hip replacement are most concerned about the survivorship of prosthesis. OBJECTIVE: To evaluate the postoperative curative effect following ce mented and cementless THR with a retrospective method, so as to provide experience for prolonging the survivoship of prosthesis. DESIGN: Randomized and controlled observation. SETTING: General Center of Orthopaedic Department, General Institute of Bone Oncology, Tangdu Hospital, Fourth Military Medical University of Chinese PLA. PARTICIPANTS: We admitted 356 patients who underwent THR from Department of Orthopaedics, Tangdu Hospital, Fourth Military Medical U niversity of Chinese PLA between March 1993 and March 2004. Among them, 298 were contacted and 105 (108 hips) followed up. The patients participated in the review voluntarily. They were of either gender and had different types of prosthesis. Prosthesis made in China was adopted before 2000 and prosthesis made in American STRIKER company after 2000: Prosthesis made in China was made of home-made bone cement; Prosthesis bone cement (import) was provided by American STRIKER prosthesis company. Home-made bone cement and import have the same components. Barium was added in both bone cement . The whole operation was con ducted by the physicians who worked in the artificial joint department after examination. METHODS: According to informal discussion summary about total hip replacement of Chinese Journal of Surgery in 1982 and Evaluation Scale of Mayo Total Hip Replacement Curative Effect, we designed follow-up table by ourselves. Totally 105 (108 hips) patients were followed up, among them, 62 (63 hips) were in the cemented group, 43 (45 hips) in the ce mentless group. Pain, function and motion range of the patients and

  8. Assessing Wear of the Acetabular Cup Using Computed Tomography: an ex vivo Study

    International Nuclear Information System (INIS)

    Purpose: To validate a clinically useful method for measuring acetabular cup wear using computed tomography (CT). Material and Methods: Eight uncemented acetabular cups were scanned twice ex vivo using CT. The linear penetration depth of the femoral component head into the cup and the thickness of the remaining polyethylene liner were measured in the CT volumes using dedicated software. Two independent examiners twice assessed each volume. The CT measurements were compared to direct measurements using a coordinate measuring device and micrometer measurements. Results: Accuracy of wear measurements expressed as penetration depth was ±0.6 and ±1.0 mm for the two examiners, respectively, with no significant differences between examiners, trials, and CT scans. Accuracy of measurements of remaining polyethylene was ±1.3 and ±1.0 mm, respectively, for the two examiners. Systematic differences between examiners were found, but no significant differences between trials and CT scans. These differences were due to different interpretations of metal artifacts in the volumes. Conclusion: The proposed CT method for evaluating wear as head penetration depth allows for reliable wear detection at a clinically relevant level. Measurements of remaining polyethylene on CT volumes are not as reliable as wear measurements owing to metal artifacts

  9. MRI morphometric hip comparison analysis of anterior acetabular labral tears

    International Nuclear Information System (INIS)

    Anterior (3 o'clock) acetabular labral tears (AALTs) have been reported to be associated with iliopsoas impingement (IPI). However, no study has examined the association between anatomical bony variables of the hip joint and AALTs. The purpose of this study was to evaluate the association between AALTs, femoroacetabular impingement (FAI) and other bony variables of the hip. Seventy-six out of 274 hip MRI records met the inclusion criteria. Two independent blinded investigators evaluated the location of acetabular labral tears (ALTs), edema at the musculotendinous junction of the iliopsoas insertion, femoral neck anteversion angle, femoral neck shaft angle, acetabular anteversion angle, alpha angle, lateral central edge angle (LCEA), acetabular index, and acetabular depth. Comparison analyses between groups were performed. Twenty-two patients had no ALTs (controls), 19 patients had AALTs, and 35 patients had ALTs not isolated at the 3 o'clock position (25 with cam-bony deformities [FAI-cam] and 10 with pincer-bony deformities [FAI-pincer]). The alpha angle mean was significantly higher (p < 0.001) in the FAI-cam group (62.7 , 95 % confidence interval [CI]: 56.2-69.2 ) compared with the AALTs group (46.9 , 95 % CI: 40.1-53.7 ). The LCEA mean was significantly higher (p < 0.001) in FAI-pincer group (41.9 , 95 % CI: 39.3 -44.5 ) compared to AALTs group (29.4 , 95 % CI: 24.2 -34.6 ). There was no statistically significant difference in any of the bony variables between the controls and the AALTs group. Our study demonstrated that AALTs are pathologically distinct and not associated with FAI or other bony abnormalities. This supports the previous studies, which proposed that AALTs are associated with IPI. (orig.)

  10. MRI morphometric hip comparison analysis of anterior acetabular labral tears

    Energy Technology Data Exchange (ETDEWEB)

    Aly, Abdel Rahman [University of Saskatchewan, Department of Physical Medicine and Rehabilitation, Saskatoon, SK (Canada); Saskatoon City Hospital, Saskatoon, SK (Canada); Rajasekaran, Sathish [HealthPointe, Pain, Spine and Sport Medicine, Alberta (Canada); Obaid, Haron [Royal University Hospital, University of Saskatchewan, Department of Medical Imaging, Saskatoon, SK (Canada)

    2013-09-15

    Anterior (3 o'clock) acetabular labral tears (AALTs) have been reported to be associated with iliopsoas impingement (IPI). However, no study has examined the association between anatomical bony variables of the hip joint and AALTs. The purpose of this study was to evaluate the association between AALTs, femoroacetabular impingement (FAI) and other bony variables of the hip. Seventy-six out of 274 hip MRI records met the inclusion criteria. Two independent blinded investigators evaluated the location of acetabular labral tears (ALTs), edema at the musculotendinous junction of the iliopsoas insertion, femoral neck anteversion angle, femoral neck shaft angle, acetabular anteversion angle, alpha angle, lateral central edge angle (LCEA), acetabular index, and acetabular depth. Comparison analyses between groups were performed. Twenty-two patients had no ALTs (controls), 19 patients had AALTs, and 35 patients had ALTs not isolated at the 3 o'clock position (25 with cam-bony deformities [FAI-cam] and 10 with pincer-bony deformities [FAI-pincer]). The alpha angle mean was significantly higher (p < 0.001) in the FAI-cam group (62.7 , 95 % confidence interval [CI]: 56.2-69.2 ) compared with the AALTs group (46.9 , 95 % CI: 40.1-53.7 ). The LCEA mean was significantly higher (p < 0.001) in FAI-pincer group (41.9 , 95 % CI: 39.3 -44.5 ) compared to AALTs group (29.4 , 95 % CI: 24.2 -34.6 ). There was no statistically significant difference in any of the bony variables between the controls and the AALTs group. Our study demonstrated that AALTs are pathologically distinct and not associated with FAI or other bony abnormalities. This supports the previous studies, which proposed that AALTs are associated with IPI. (orig.)

  11. Primary Stability Recognition of the Newly Designed Cementless Femoral Stem Using Digital Signal Processing

    OpenAIRE

    Mohd Yusof Baharuddin; Sh-Hussain Salleh; Mahyar Hamedi; Ahmad Hafiz Zulkifly; Muhammad Hisyam Lee; Alias Mohd Noor; Harris, Arief Ruhullah A.; Norazman Abdul Majid

    2014-01-01

    Stress shielding and micromotion are two major issues which determine the success of newly designed cementless femoral stems. The correlation of experimental validation with finite element analysis (FEA) is commonly used to evaluate the stress distribution and fixation stability of the stem within the femoral canal. This paper focused on the applications of feature extraction and pattern recognition using support vector machine (SVM) to determine the primary stability of the implant. We measu...

  12. A biodegradable gentamicin-hydroxyapatite-coating for infection prophylaxis in cementless hip prostheses

    OpenAIRE

    Neut, D.; RJB Dijkstra; JI Thompson; Kavanagh, C.; HC van der Mei; Busscher HJ

    2015-01-01

    A degradable, poly (lactic-co-glycolic acid) (PLGA), gentamicin-loaded prophylactic coating for hydroxyapatite (HA)-coated cementless hip prostheses is developed with similar antibacterial efficacy as offered by gentamicin-loaded cements for fixing traditional, cemented prostheses in bone. We describe the development pathway, from in vitro investigation of antibiotic release and antibacterial properties of this PLGA-gentamicin-HA-coating in different in vitro models to an evaluation of its ef...

  13. Relationship between Wiberg's lateral center edge angle, Lequesne's acetabular index, and medial acetabular bone stock

    Energy Technology Data Exchange (ETDEWEB)

    Werner, Clement M.L. [Balgrist University Hospital Zurich, Department of Orthopaedics, Zurich (Switzerland); University of Maryland Medical Systems, R. Adams Cowley Shock Trauma Center, Baltimore, MD (United States); Copeland, Carol E.; Stromberg, Jeff; Turen, Clifford H. [University of Maryland Medical Systems, R. Adams Cowley Shock Trauma Center, Baltimore, MD (United States); Ruckstuhl, Thomas; Bouaicha, Samy [Balgrist University Hospital Zurich, Department of Orthopaedics, Zurich (Switzerland)

    2011-11-15

    Knowledge of acetabular anatomy is crucial for cup positioning in total hip replacement. Medial wall thickness of the acetabulum is known to correlate with the degree of developmental dysplasia of the hip (DDH). No data exist about the relationship of routinely used radiographic parameters such as Wiberg's lateral center edge angle (LCE-angle) or Lequesne's acetabular index (AI) with thickness of the medial acetabular wall in the general population. The aim of our study was to clarify the relationship between LCE, AI, and thickness of the medial acetabular wall. Measurements on plain radiographs (LCE and AI) and axial CT scans (quadrilateral plate acetabular distance QPAD) of 1,201 individuals (2,402 hips) were obtained using a PACS imaging program and statistical analyses were performed. The mean thickness of the medial acetabulum bone stock (QPAD) was 1.08 mm (95% CI: 1.05-1.10) with a range of 0.1 to 8.8 mm. For pathological values of either the LCE (<20 ) or the AI (>12 ) the medial acetabular wall showed to be thicker than in radiological normal hips. The overall correlation between coxometric indices and medial acetabular was weak for LCE (r =-0.21. 95% CI [-0.25, -0.17]) and moderate for AI (r = 0.37, [0.33, 0.41]). We did not find a linear relationship between Wiberg's lateral center edge angle, Lequesne's acetabular index and medial acetabular bone stock in radiological normal hips but medial acetabular wall thickness increases with dysplastic indices. (orig.)

  14. Treatment of acetabular dysplasia by triple pelvic osteotomy and its short-term results

    OpenAIRE

    Dogan, Ahmet; Zorer, Gazi; Ozer, Utku Erdem

    2004-01-01

    Objectives: We evaluated the effect of triple pelvic osteotomy on acetabular coverage and its clinical implications by clinical and radiographic parameters in patients with acetabular dysplasia. Methods: Triple pelvic osteotomy was performed in 21 hips of 19 patients (13 females, 6 males; mean age during operation 16.3 years; range 8 to 32 years). Acetabular dysplasia was bilateral in two, and unilateral in 17 patients. Etiology was developmental dysplasia of the hip in 12 patients, Legg-C...

  15. Surface composition analysis of failed cementless CoCr- and Ti-base-alloy total hip implants.

    Science.gov (United States)

    Decking, R; Reuter, P; Hüttner, M; Puhl, W; Claes, L E; Scharf, H P

    2003-02-15

    The surfaces of retrieved failed cementless total hip implants made of cobalt-chromium-molybdenum casting alloy and of wrought titanium 6-aluminum 4-vanadium alloy were studied with the use of scanning-electron microscopy (SEM), energy-dispersive X-ray analysis (EDX) and X-ray photoelectron spectroscopy (XPS). New implants of the same make served as controls. The XPS scans revealed a dense carbon layer on the entire analyzed specimen. The relative composition of the titanium alloy implants showed an overall agreement with the international standards for implants for surgery, and the overall surface composition did not change over the period of the implantation. However, an inhomogeneous distribution of the constituents could be demonstrated in the retrieved as well as in the new MEC-screw rings made of TiAl6V4 alloy, an implant that has been linked to a high early failure rate. In the CoCr-alloy components (Lord-screw rings) a high percentage of aluminum, mainly organized in aluminum inclusions, was found in the retrieved as well as in the new implants. PMID:12516084

  16. Experimental and Numerical Analyses of the Pull-out Response of a Steel Post/Bovine Bone Cementless Fixation

    Institute of Scientific and Technical Information of China (English)

    Khaled Gammoudi; Mohamed Kharrat; Maher Dammak

    2012-01-01

    Effect of initial interference fit on pull-out strength in cementless fixation between bovine tibia and smooth stainless steel post was investigated in this study.Compressive behavior of bovine spongious bone was studied using mechanical testing in order to evaluate the elastic-plastic properties in different regions of the proximal tibia.Friction tests were carried out in the aim to evaluate the friction behavior of the contact between bovine spongious bone and stainless steel.A cylindrical stainless steel post inserted in a pre-drilled bovine tibia with an initial interference fit was taken as an in vitro model to assess the contribution of post fixation to the initial stability of the Total Knee Arthroplasty (TKA) tibial component.Pull-out experiments were carried out for different initial interference fits.Finite Element Models (FEM) using local elastic-plastic properties of the bovine bone were developed for the analysis of the experimental ultimate pull-out force results.At the post/bone interface,Coulomb friction was considered in the FEM calculations with pressure-dependent friction coefficient.It was found that the FEM results of the ultimate force are in good agreement with the experimental results.The analysis of the FEM interfacial stresses indicates that the micro-slip initiation depends on the local bone properties.

  17. The effect of abductor muscle and anterior-posterior hip contact load simulation on the in-vitro primary stability of a cementless hip stem

    Directory of Open Access Journals (Sweden)

    Frei Hanspeter

    2010-06-01

    Full Text Available Abstract Background In-vitro mechanical tests are commonly performed to assess pre-clinically the effect of implant design on the stability of hip endoprostheses. There is no standard protocol for these tests, and the forces applied vary between studies. This study examines the effect of the abductor force with and without application of the anterior-posterior hip contact force in the in-vitro assessment of cementless hip implant stability. Methods Cementless stems (VerSys Fiber Metal were implanted in twelve composite femurs which were divided into two groups: group 1 (N = 6 was loaded with the hip contact force only, whereas group 2 (N = 6 was additionally subjected to an abductor force. Both groups were subjected to the same cranial-caudal hip contact force component, 2.3 times body weight (BW and each specimen was subjected to three levels of anterior-posterior hip contact load: 0, -0.1 to 0.3 BW (walking, and -0.1 to 0.6 BW (stair climbing. The implant migration and micromotion relative to the femur was measured using a custom-built system comprised of 6 LVDT sensors. Results Substantially higher implant motion was observed when the anterior-posterior force was 0.6BW compared to the lower anterior-posterior load levels, particularly distally and in retroversion. The abductor load had little effect on implant motion when simulating walking, but resulted in significantly less motion than the hip contact force alone when simulating stair climbing. Conclusions The anterior-posterior component of the hip contact load has a significant effect on the axial motion of the stem relative to the bone. Inclusion of the abductor force had a stabilizing effect on the implant motion when simulating stair climbing.

  18. Validation of a new radiographic measurement of acetabular version: the transverse axis distance (TAD)

    Energy Technology Data Exchange (ETDEWEB)

    Nitschke, Ashley [University of Colorado School of Medicine, University of Colorado Denver, Division of Musculoskeletal Radiology, Department of Radiology, Aurora, CO (United States); Lambert, Jeffery R. [University of Colorado, Department of Biostatistics and Informatics, Colorado School of Public Health, Aurora, CO (United States); Glueck, Deborah H. [University of Colorado, Department of Biostatistics and Informatics, Colorado School of Public Health, Aurora, CO (United States); University of Colorado School of Medicine, University of Colorado Denver, Department of Radiology, Aurora, CO (United States); Jesse, Mary Kristen; Strickland, Colin [University of Colorado School of Medicine, University of Colorado Denver, Division of Musculoskeletal Radiology, Department of Radiology and Orthopaedics, Aurora, CO (United States); Mei-Dan, Omer [University of Colorado School of Medicine, University of Colorado Denver, Division of Sports Medicine and Hip Preservation, Department of Orthopaedics, Aurora, CO (United States); Petersen, Brian [University of Colorado School of Medicine, University of Colorado Denver, Division of Musculoskeletal Radiology, Department of Radiology and Orthopaedics, Aurora, CO (United States); Inland Imaging, Division of Musculoskeletal Radiology, Spokane, WA (United States)

    2015-11-15

    This study has three aims: (1) validate a new radiographic measure of acetabular version, the transverse axis distance (TAD) by showing equivalent TAD accuracy in predicting CT equatorial acetabular version when compared to a previously validated, but more cumbersome, radiographic measure, the p/a ratio; (2) establish predictive equations of CT acetabular version from TAD; (3) calculate a sensitive and specific cut point for predicting excessive CT acetabular anteversion using TAD. A 14-month retrospective review was performed of patients who had undergone a dedicated MSK CT pelvis study and who also had a technically adequate AP pelvis radiograph. Two trained observers measured the radiographic p/a ratio, TAD, and CT acetabular equatorial version for 110 hips on a PACS workstation. Mixed model analysis was used to find prediction equations, and ROC analysis was used to evaluate the diagnostic accuracy of p/a ratio and TAD. CT equatorial acetabular version can accurately be predicted from either p/a ratio (p < 0.001) or TAD (p < 0.001). The diagnostic accuracies of p/a ratio and TAD are comparable (p =0.46). Patients whose TAD is higher than 17 mm may have excessive acetabular anteversion. For that cutpoint, the sensitivity of TAD is 0.73, with specificity of 0.82. TAD is an accurate radiographic predictor of CT acetabular anteversion and provides an easy-to-use and intuitive point-of-care assessment of acetabular version in patients with hip pain. (orig.)

  19. Difference in the acetabular cup orientation in standing and supine radiographs.

    Science.gov (United States)

    Khan, Munir; Beckingsale, Tom; Marsh, Martin; Holland, Jim

    2016-09-01

    Acetabular orientation changes with that of the pelvis during lying and standing. This study was designed to measure these changes. We assessed 17 BHR replacements using EBRA software. The mean acetabular anteversion was more (p = 0.02) on erect than supine radiographs. Linear regression analysis showed that anteversion and inclination increased in some while decreased in others, and Bland and Altman analysis showed wide limits of agreement. The changes in acetabular orientation are thus subject to significant variations between the patients. We suggest studying the factors affecting acetabular orientation in standing to help reduce joint reaction forces and improve outcomes. PMID:27408490

  20. Validation of a new radiographic measurement of acetabular version: the transverse axis distance (TAD)

    International Nuclear Information System (INIS)

    This study has three aims: (1) validate a new radiographic measure of acetabular version, the transverse axis distance (TAD) by showing equivalent TAD accuracy in predicting CT equatorial acetabular version when compared to a previously validated, but more cumbersome, radiographic measure, the p/a ratio; (2) establish predictive equations of CT acetabular version from TAD; (3) calculate a sensitive and specific cut point for predicting excessive CT acetabular anteversion using TAD. A 14-month retrospective review was performed of patients who had undergone a dedicated MSK CT pelvis study and who also had a technically adequate AP pelvis radiograph. Two trained observers measured the radiographic p/a ratio, TAD, and CT acetabular equatorial version for 110 hips on a PACS workstation. Mixed model analysis was used to find prediction equations, and ROC analysis was used to evaluate the diagnostic accuracy of p/a ratio and TAD. CT equatorial acetabular version can accurately be predicted from either p/a ratio (p < 0.001) or TAD (p < 0.001). The diagnostic accuracies of p/a ratio and TAD are comparable (p =0.46). Patients whose TAD is higher than 17 mm may have excessive acetabular anteversion. For that cutpoint, the sensitivity of TAD is 0.73, with specificity of 0.82. TAD is an accurate radiographic predictor of CT acetabular anteversion and provides an easy-to-use and intuitive point-of-care assessment of acetabular version in patients with hip pain. (orig.)

  1. PATHOLOGICAL AND MORPHOLOGICAL RESEARCH OF EXPERIMENTAL ACETABULAR DYSPLASIA

    Institute of Scientific and Technical Information of China (English)

    张自明; 马瑞雪; 吉士俊; 牛之彬

    2004-01-01

    Objective To investigate the pathological mechanism of hip dysplasia. Methods The left knee joints of eighteen rabbits were fixed in extending position with plaster cylinder for four weeks, but their hip joints were flexed. The right side served as control. Roentgenogram was made in all animals. The changes of the xray films and the pathological findings between left and right hips were compared. Results Appearance of hip dysplasia was obvious at four weeks after plaster fixation. There were pathological changes, including shallow acetabulum and flat femoral head, increased acetabular index and decreased acetabular head index on the x-ray films.Conclusion The hip dysplasia is the result of prolonged extending position of the knee joint. Abnormal knee posture seems to be one of the important factors of hip dysplasia. This kind of deformation may be worsened with time.

  2. Acetabular prosthesis: Proff of migration with ruler and pencil?

    International Nuclear Information System (INIS)

    Conventional X-ray films were made with varying degrees of tilt of a pelvic phantom containing an acetabular prosthesis. The position of the prosthesis was then reconstructed graphically. The measurement errors were calculated and an estimate was made for the tilt. There is a linear correlation between the measurement error and the tilt of the prosthesis. Therefore a tilt dependent maximum error can be calculated. This error is very small for small degrees of tilt, so that acetabular migration can in this instance be evaluated with greater confidence than with other graphical methods. The error also correlates with the determination of the selected region of the acetabulum, but not with the position of the central focus spot or image magnification. (orig.)

  3. Nonunion of acetabular fractures: evaluation with interactive multiplanar CT

    International Nuclear Information System (INIS)

    Nonunions involving fractures of the acetabulum are reportedly rare, with few citings and little discussion in the literature. It is possible that acetabular nonunions go undetected because imaging of the acetabulum is difficult by conventional radiography. We report two cases of fracture nonunion involving the weight-bearing surface of the acetabulum diagnosed with the aid of computed tomography (CT) and a newly developed interactive 2D/3D orthotool that uniquely processes and reformats routine CT data. The interactive 2D/3D orthotool is a sophisticated computer program that allows dynamic viewing of standard multiplanar reconstructions in the axial, coronal, and sagittal planes as well as multiple oblique projections. The 2D/3D orthotool provides on screen correlation of two-dimensional multiplanar images with three-dimensional reconstructions of the pelvis. The authors found this capability ideally suited for studying fractures with off-axis orientation such as those through the acetabular dome, greatly facilitating the diagnosis of nonunion

  4. Transosseous Acetabular Labral Repair as an Alternative to Anchors

    OpenAIRE

    Pérez-Carro, Luis; Cabello, Andres Gonzalez; Rakha, Mohamed Ibrahim; Patnaik, Sarthak; Centeno, Elias; Miranda, Victor; Fernández, Ana Alfonso

    2015-01-01

    Labral tears are the most common pathology in patients undergoing hip arthroscopy and the most common cause of mechanical hip symptoms. Labral repair techniques have been described in the literature using suture anchors placed as close as possible to the acetabular rim without penetrating the articular surface. Optimal surgical technique for labral repair is very important, and an inappropriate entry point and guide angulation may lead to intra-articular penetration of the anchor, chondral da...

  5. Imaging diagnosis of acetabular dysplastic coxarthrosis in adult

    International Nuclear Information System (INIS)

    Objective: To investigate the imaging diagnosis of acetabular dysplastic coxarthrosis. Method: The imaging of the acetabular dysplasia was analyzed in 51 patients (87 hips). All but four patients were women. The age ranged from 22 to 78 years, and the mean age was 42.6 years. Pelvis radiographs were studied in all cases, and CT scan was performed in 18 cases and MRI in 10 cases. Results: The fundamental signs on the plain film included shallow acetabulum, increased obliquity and insufficient coverage of the femoral head by the acetabulum. The CE angles were determined in all the cases, ranging from -10 degree to 30 degree, mean 12.9 degree. The sharp angles ranged from 35 degree to 67 degree, mean 45.3 degree. The secondary osteoarthritis were revealed in 75 hips (84.2%). 54 hips (62.1%) had cyst-like lesions in weight-bear area of the acetabulum or femoral head. 19 hips had subluxation of femoral head. CT and MRI displayed small cyst-like lesions and forward shift of the femoral head, which could not be shown on plain film, respectively in 13 and 10 hips. Conclusion: The cyst-like lesion of subarticular region is a common sign in acetabular dysplastic coxarthrosis. CT or MRI can show the early osteolytic lesion and forward subluxations

  6. 自体骨植骨在成人先天性髋臼发育不良全髋关节置换术中的疗效分析%Autogenous bone grafting in total hip arthroplasty for congenital acetabular dysplasia

    Institute of Scientific and Technical Information of China (English)

    周垂宝; 李明; 张元凯

    2012-01-01

    To discuss the effect of the femoral-head autograft in uncemented total hip arthroplasty for congenital acetabular dysplasia. Methods 21 patients(24 hips) with acetabular dysplasia (Crowe type Ⅱ orⅢ ) from August 2007 to May 2010 received femoral head autograft in cementless total hip arthroplasty for acetabular dysplasia to reconstruct acetabula. Classified Harris Hip Score (CHHS) and imaging examination were used in the follow-up visit. Results There was a significant difference between the pre and post operation according to CHHS (P <0.05). At an average follow-up of 27 months,all the patients had excellent clinical results. Neither acetabular autograft resorption nor non-union was observed. Conclusion Using femoral-head autograft was an effect method in uncemented total hip arthroplasty for the acetabular dysplasia.%目的 分析成人先天性髋臼发育不良全髋关节置换术中使用自体骨结构性移植重建髋臼的疗效.方法 2007年8月至2010年5月手术治疗先天性髋臼发育不良CroweⅡ、Ⅲ型患者21例(24髋),男3例(3髋),女18例(21髋),行非骨水泥型全髋关节置换术,应用自体股骨头植骨重建髋臼,随访指标为Harris评分和影像学检查.结果 Harris评分统计分析显示,术前与术后差异有统计学意义(P<0.05),移植骨愈合,无移植骨的吸收.结论 自体骨结构性植骨在非骨水泥型全髋关节置换治疗先天性髋臼发育不良中有良好疗效.

  7. 21 CFR 888.3370 - Hip joint (hemi-hip) acetabular metal cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3370 Section 888.3370 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... (hemi-hip) acetabular metal cemented prosthesis. (a) Identification. A hip joint (hemi-hip) acetabular metal cemented prosthesis is a device intended to be implanted to replace a portion of the hip...

  8. Comparison of acetabular version angle measurements between prone and reformatted supine computed tomography images

    Energy Technology Data Exchange (ETDEWEB)

    Chong, Le Roy [Changi General Hospital, Department of Radiology, Singapore (Singapore); Too, Chow Wei [Singapore General Hospital, Department of Diagnostic Radiology, Singapore (Singapore)

    2014-03-15

    To compare acetabular version angle measurements of CT scans in the prone and reformatted supine positions. CT acetabular version angle measurements have previously been done in the prone position to correct for pelvic tilt. With the advent of multidetector CT, recent studies have evaluated acetabular version angles measured in the supine position. To our knowledge, a comparison between these two approaches has not been performed. Case series in which consecutive CT urography studies of 49 adult patients performed in both prone and supine positions were retrospectively reviewed, and acetabular version angles of both hips measured. Retrospective review of 49 consecutive CT urography studies performed in both prone and supine positions was done, and acetabular version angles of both hips were measured. Two radiologists measured the acetabular version angles independently. Multiplanar reformation of the supine CT images was performed to compensate for pelvic tilt and rotation prior to angle measurements. There was excellent interobserver agreement between the two readers (ICC = 0.90). Acetabular version angle measurements from the prone CT images were larger compared to reformatted supine images (24.0 and 21.3 , respectively, p < 0.0001), with greater angles found in women. There was strong correlation between supine and prone acetabular version angle measurements with a Pearson correlation coefficient of 0.743. Acetabular version angles measured from prone and reformatted supine CT images show strong correlation but are significantly different with larger angles obtained from the former and in women; clinical implications of these findings may require further study in other to determine the best method of version angle measurement. CT acetabular version angle measurement is also reliable with excellent interobserver correlation. (orig.)

  9. Measuring acetabular cup orientation on antero-posterior radiographs of the hip after total hip arthroplasty with a vector arithmetic radiological method. Is it valid and verified for daily clinical practice?

    Energy Technology Data Exchange (ETDEWEB)

    Craiovan, B.; Weber, M.; Worlicek, M.; Schneider, M.; Springorum, H.R.; Grifka, J.; Renkawitz, T. [University Medical Center Regensburg, Bad Abbach/Regensburg (Germany). Orthopedic Surgery; Zeman, F. [University Medical Center Regensburg, Bad Abbach/Regensburg (Germany). Center for Clinical Studies

    2016-06-15

    The aim of this prospective study is to validate a vector arithmetic method for measuring acetabular cup orientation after total hip arthroplasty (THA) and to verify the clinical practice. We measured cup anteversion and inclination of 123 patients after cementless primary THA twice by two examiners on AP pelvic radiographs with a vector arithmetic method and compared with a 3D-CT based reconstruction model within the same radiographic coronal plane. The mean difference between the radiographic and the 3D-CT measurements was -1.4 ±3.9 for inclination and 0.8 ±7.9 for anteversion with excellent correlation for inclination (r=0.81, p < 0.001) and moderate correlation for anteversion (r=0.65, p < 0.001). The intraclass correlation coefficient for measurements on radiographs ranged from 0.98 (95%-CI: 0.98; 0.99) for the first observer to 0.94 (95%-CI: 0.92; 0.96) for the second observer. The interrater reliability was 0.96 (95%-CI: 0.93; 0.98) for inclination and 0.93 (95%-CI: 0.85; 0.96) for anteversion. The largest errors in measurements were associated with an extraordinary pelvic tilt. In order to get a valuable measurement for measuring cup position after THA on pelvic radiographs by this vector arithmetic method, there is a need for a correct postoperative ap view, with special regards to the pelvic tilt for the future.

  10. MR arthrography for evaluation of the acetabular labrum

    Energy Technology Data Exchange (ETDEWEB)

    Petersilge, C.A. [Musculoskeletal and Emergency Radiology, Hillcrest Hospital, Mayfield Heights, OH (United States); Radiology and Orthopedic Surgery, Case Western Reserve Univ., Mayfield Heights, OH (United States)

    2001-08-01

    MR arthrography of the hip has provided new insights into the lesions underlying mechanical hip pain. Until now evaluation of these structures, especially the acetabular labrum, has been limited. With the joint distention provided by MR arthrography, labral detachments and intrasubstance tears can be identified and differentiated from the many varied appearances of the asymptomatic labrum. This article reviews the normal anatomy of the hip, the clinical presentation of internal derangement and the technique for performing MR arthrography. The variations in morphology and signal of the asymptomatic labrum are reviewed as well as the appearance of the abnormal labrum. (orig.)

  11. Antibacterial Efficacy of a New Gentamicin-Coating for Cementless Prostheses Compared to Gentamicin-Loaded Bone Cement

    NARCIS (Netherlands)

    Neut, Danielle; Dijkstra, Rene J. B.; Thompson, Jonathan I.; van der Mei, Henny C.; Busscher, Henk J.

    2011-01-01

    Cementless prostheses are increasingly popular but require alternative prophylactic measures than the use of antibiotic-loaded bone cements. Here, we determine the 24-h growth inhibition of gentamicin-releasing coatings from grit-blasted and porous-coated titanium alloys, and compare their antibacte

  12. Computer-based gait analysis of dogs: evaluation of kinetic and kinematic parameters after cemented and cementless total hip replacement.

    Science.gov (United States)

    Drüen, S; Böddeker, J; Meyer-Lindenberg, A; Fehr, M; Nolte, I; Wefstaedt, P

    2012-01-01

    To date it is unclear whether cementless total hip replacement (THR) in dogs is of clinical advantage in comparison to cemented THR with regard to lameness improvement. Thus the aim of this study was to compare objectively the development of the gait pattern after cemented and cementless THR in dogs. For this purpose, 18 adult dogs with hip dysplasia underwent computer-based gait analysis on an instrumented treadmill prior to unilateral THR and then again ten days, four weeks and four months after surgery. Analysed kinetic parameters were symmetry indices (SI) of vertical ground reaction forces (GRF), which included peak vertical forces (PFz), mean vertical forces (MFz), vertical impulse (IFz), and vertical ground reaction forces of the arthroplasty limbs only. Analysed kinematic parameters were range-of-motion and the flexion and extension angles of hip, stifle and hock joints. The symmetry indice for PVF, MFz and IFz decreased to a value less than six in both THR groups four months after surgery, which is defined as not lame. Improvement in lameness of the arthroplasty limbs during the examination period of four months was not significantly different between the cemented and cementless groups. The results suggest that within a short-term observation period of four months after surgery, neither cementless nor cemented THR have a greater advantage with regard to lameness improvement. Additional studies with larger pools of subjects and longer time periods for follow-up examinations are necessary to verify these findings. PMID:22828804

  13. Effects of Materials of Cementless Femoral Stem on the Functional Adaptation of Bone

    Institute of Scientific and Technical Information of China (English)

    He Gong; Wei Wu; Juan Fang; Xin Dong; Meisheng Zhao; Tongtong Guo

    2012-01-01

    The objective of this paper is to identify the effects of materials of cementless femoral stem on the functional adaptive behaviors of bone.The remodeling behaviors of a two-dimensional simplified model of cementless hip prosthesis with stiff stem,flexible 'iso-elastic' stem,one-dimensional Functionally Graded Material (FGM) stem and two-dimensional FGM stem for the period of four years after prosthesis replacement were quantified by incorporating the bone remodeling algorithm with finite element analysis.The distributions of bone density,von Mises stress,and interface shear stress were obtained.The results show that two-dimensional FGM stem may produce more mechanical stimuli and more uniform interface shear stress compared with the stems made of other materials,thus the host bone is well preserved.Accordingly,the two-dimensional FGM stem is an appropriate femoral implant from a biomechanical point of view.The numerical simulation in this paper can provide a quantitative computational paradigm for the changes of bone morphology caused by implants,which can help to improve the design of implant to reduce stress shielding and the risk of bone-prosthesis interface failure.

  14. FUNCTIONAL OUTCOME OF SURGICAL MANAGEMENT OF ACETABULAR FRACTURES BY INTERNAL FIXATION

    Directory of Open Access Journals (Sweden)

    Sagar

    2015-06-01

    Full Text Available BACKGROUND: The treatment of acetabular fractures has seen major advances in the field of orthopaedic traumatology. Conservative treatment of acetabular fractures leads to poor results. Newer diagnostic tools like the Computed Tomography (CT scan help in analyzing the three dimensional disturbance in the normal anatomy and plan the surgical management accordingly. In recent years operative treatment has become the treat ment of choice in the management of acetabular fractures as precise anatomical reduction with adequate internal fixation can be attained. OBJECTIVES : To evaluate the functional outcome of operatively managed acetabular fractures , and assess the efficacy of operative fixation of acetabular fractures , and also study the complications of operative fixation of acetabular fractures. MATERIALS AND METHODS: Fifty five patients (49 male & six female admitted to Sanjay Gandhi Institute of Trauma and Orthopaedics wi th acetabular fractures underwent open reduction and internal fixation. All patients were evaluated with Matta et al score with a minimum of follow up of six months. RESULTS: There were 24 (43.6% patients with bicolumnar fractures , 15(27.3% had posterior column fractures , 10(18.1% had posterior wall fractures , five (9.1% had transverse fractures , and one (1.8% patient had an anterior column fracture. Full weight bearing was attained in thirty five (63.6% patients in 16 weeks and in twenty (36.4% pati ents after 16 weeks. Forty five (81.8% patients were free of complications. According to Matta et al score 27(49.1% had excellent , 15(27.3% had good , nine (16.4% had fair , and four (7.3% had poor results. CONCLUSION: Open reduction and internal fixati on of acetabular fractures is a reliable technique , minimizes healing time and provides congruent joint reduction. Operative treatment of acetabular fractures results in predictable union and good clinical results with a low rate of complications.

  15. Acetabular fractures following rugby tackles: a case series

    Directory of Open Access Journals (Sweden)

    Morris Seamus

    2011-10-01

    Full Text Available Abstract Introduction Rugby is the third most popular team contact sport in the world and is increasing in popularity. In 1995, rugby in Europe turned professional, and with this has come an increased rate of injury. Case presentation In a six-month period from July to December, two open reduction and internal fixations of acetabular fractures were performed in young Caucasian men (16 and 24 years old who sustained their injuries after rugby tackles. Both of these cases are described as well as the biomechanical factors contributing to the fracture and the recovery. Acetabular fractures of the hip during sport are rare occurrences. Conclusion Our recent experience of two cases over a six-month period creates concern that these high-energy injuries may become more frequent as rugby continues to adopt advanced training regimens. Protective equipment is unlikely to reduce the forces imparted across the hip joint; however, limiting 'the tackle' to only two players may well reduce the likelihood of this life-altering injury.

  16. Acetabular fractures following rugby tackles: a case series

    LENUS (Irish Health Repository)

    Good, Daniel W

    2011-10-05

    Abstract Introduction Rugby is the third most popular team contact sport in the world and is increasing in popularity. In 1995, rugby in Europe turned professional, and with this has come an increased rate of injury. Case presentation In a six-month period from July to December, two open reduction and internal fixations of acetabular fractures were performed in young Caucasian men (16 and 24 years old) who sustained their injuries after rugby tackles. Both of these cases are described as well as the biomechanical factors contributing to the fracture and the recovery. Acetabular fractures of the hip during sport are rare occurrences. Conclusion Our recent experience of two cases over a six-month period creates concern that these high-energy injuries may become more frequent as rugby continues to adopt advanced training regimens. Protective equipment is unlikely to reduce the forces imparted across the hip joint; however, limiting \\'the tackle\\' to only two players may well reduce the likelihood of this life-altering injury.

  17. Efficient radiologic diagnosis of pelvic and acetabular trauma

    International Nuclear Information System (INIS)

    In spite of the widespread availability of CT scanners, conventional X-ray radiographs remain the basic imaging modality in patients with pelvic and/or acetabular trauma. However, the extent of their use will depend on local utilities (e.g., availability of CT scanners) and on the patient's clinical condition. Regarding the inaccuracy of conventional radiography in the diagnosis of injuries of the dorsal pelvic ring and of the acetabulum, computed tomography represents the most important imaging modality in the clinically stable patient. CT provides an exact staging of the extent of trauma and allows for differentiation of pelvic instabilities. CT clearly demonstrates the severity of acetabular trauma and is superior in the detection of local complicating factors, i.e., impressions fractures and (sub-)luxations of the femoral head as well as free intraarticular fragments. CT findings provide the basis for definite treatment regimens of the injured patient. By extension of the examination, all relevant organs and systems (craniospinal, cardiovascular, gastrointestinal, respiratory, genitourinary) can be imaged during one session. The speed of spiral CT scanners and their diagnostic accuracy will play a major role in the management of, especially, polytraumatized patients. The indication for angiography with the option of therapeutic embolization exists if a pelvic bleeding persists even after reposition and operative fixation of the injury. (orig.)

  18. Para-acetabular peritendinitis calcarea; its radiographic manifestations

    International Nuclear Information System (INIS)

    Peritendinitis calcarea and os acetabuli have long been confused during interpretations of hip-joint radiographs. Such confusion is reflected in the medical literature. The present study differentiated these two entities according to their interval radiographic progression and regression. There were 137 instances of para-acetabular calcifications among 110 subjects (59 men and 51 women), whose mean age was 46.8 years at the time of their initial detection. Twenty-six of the subjects had lumbago, which was probably unrelated. Other abnormalities including narrowed intervertebral spaces, scoliosis, and spondylolysis were observed in 21 of the subjects. These could have been responsible for any symptoms they had had, but none of the subjects complained of local hip-joint pain when the radiographs in question were made. Ninety-three of these instances of calcification were reviewed by means of serial radiographs. Interval changes in the sizes and shapes of the calcifications occurred among 90 of them, indicative of the latent type of peritendinitis calcarea. No interval changes were noted in the remaining three cases, indicating they were secondary ossification centers; namely, os acetabuli. This study showed that in asymptomatic adults, most para-acetabular calcifications were really not os acetabuli, but actually peritendinitis calcarea. (author)

  19. Subchondral Insufficiency Fracture of the Femoral Head Caused by Excessive Lateralization of the Acetabular Rim

    Science.gov (United States)

    Kimura, Tetsuya; Goto, Tomohiro; Hamada, Daisuke; Tsutsui, Takahiko; Wada, Keizo; Fukuta, Shoji; Nagamachi, Akihiro; Sairyo, Koichi

    2016-01-01

    We present a case of a 53-year-old woman with subchondral insufficiency fracture (SIF) of the femoral head without history of severe osteoporosis or overexertion. Plain radiographs showed acetabular overcoverage with excessive lateralization of the acetabular rim. A diagnosis of SIF was made by typical MRI findings of SIF. The lesion occurred at the antipodes of the extended rim. Increased mechanical stress over the femoral head due to impingement against the excess bone was suspected as a cause of SIF. The distinct femoral head deformity is consistent with this hypothesis. This is the first report of SIF associated with acetabular overcoverage. PMID:27293935

  20. An interactive surgical planning tool for acetabular fractures: initial results

    Directory of Open Access Journals (Sweden)

    Marincek Borut

    2010-08-01

    Full Text Available Abstract Background Acetabular fractures still are among the most challenging fractures to treat because of complex anatomy, involved surgical access to fracture sites and the relatively low incidence of these lesions. Proper evaluation and surgical planning is necessary to achieve anatomic reduction of the articular surface and stable fixation of the pelvic ring. The goal of this study was to test the feasibility of preoperative surgical planning in acetabular fractures using a new prototype planning tool based on an interactive virtual reality-style environment. Methods 7 patients (5 male and 2 female; median age 53 y (25 to 92 y with an acetabular fracture were prospectively included. Exclusion criterions were simple wall fractures, cases with anticipated surgical dislocation of the femoral head for joint debridement and accurate fracture reduction. According to the Letournel classification 4 cases had two column fractures, 2 cases had anterior column fractures and 1 case had a T-shaped fracture including a posterior wall fracture. The workflow included following steps: (1 Formation of a patient-specific bone model from preoperative computed tomography scans, (2 interactive virtual fracture reduction with visuo-haptic feedback, (3 virtual fracture fixation using common osteosynthesis implants and (4 measurement of implant position relative to landmarks. The surgeon manually contoured osteosynthesis plates preoperatively according to the virtually defined deformation. Screenshots including all measurements for the OR were available. The tool was validated comparing the preoperative planning and postoperative results by 3D-superimposition. Results Preoperative planning was feasible in all cases. In 6 of 7 cases superimposition of preoperative planning and postoperative follow-up CT showed a good to excellent correlation. In one case part of the procedure had to be changed due to impossibility of fracture reduction from an ilioinguinal approach

  1. Use of computer assisted orthopedic surgery in pelvic and acetabular trauma

    OpenAIRE

    Amr Abdelgawad; Ralitsa Akins; Kanlic, Enes M

    2011-01-01

    Computer assisted orthopedic surgery (CAOS) is a recent concept inorthopedics. Its use in orthopedic trauma is becoming more popular.Pelvic and acetabular trauma is one of the applications where CAOScan play an important role to facilitate the surgery. In this review article, we provide an overview of the structure of CAOS with specialemphasis on its role in pelvic and acetabular trauma. Th e use of CAOShas many advantages in the field of orthopedic trauma, however, manyobstacles are still pr...

  2. SeIectlng the incision In the surgical treatment of acetabular fractures

    OpenAIRE

    Asik, Mehmet; Basturk, Sırrı; Akpinar, Sercan; Taser, Omer; Akalin, Yilmaz

    2004-01-01

    In acetabular fractures which may have totally differing three dimensional appearances selecting the incision directly influences the quality, directly influences the quality of the surgical reduction and, therefore, the postoperative clinical outcome of the patierit. Becauseof this, it is a subject that has to be meticulously done. According to the fracture types, we used 6 distinct incisions on the 35 acetabular fractures which were operated in our clinic between 1988 and 1992. We presente...

  3. A novel classification to guide total hip arthroplasty for adult acetabular dysplasia

    OpenAIRE

    Zhu, Chen; CHENG, MENG-QI; Cheng, Tao; MA, RUI-XIANG; Kong, Rong; GUO, YONG-YUAN; Qin, Hui; SHI, SI FENG; Zhang, Xian-long

    2013-01-01

    In the field of hip arthroplasties, the secondary fixation of the implants depends directly on the quality of the primary stability. A good acetabular fit and metaphyseal filling between the prostheses and implants improve the initial stabilization, and optimize the transmission of forces to the bone. A precise knowledge of the three-dimensional acetabular or femoral shape is essential to the selection of adapted implants. A total of 63 patients diagnosed with developmental dysplasia were ana...

  4. Numerical modelling of the pelvis and acetabular construct following hip arthroplasty

    OpenAIRE

    Phillips, Andrew T. M.

    2005-01-01

    The study presents finite element models of the acetabular construct and the pelvis. Particular attention is given to investigating the behaviour of the acetabular construct following revision hip arthroplasty, carried out using the Slooff-Ling impaction grafting technique. Mechanical tests are carried out on bone graft, and constitutive models are developed to describe its non-linear elasto-plastic behaviour, for inclusion in finite element analyses. Impaction of bone graft was found to have...

  5. Treatment of severe bone deficiency in acetabular revision surgery using a reinforcement device and bone grafting

    Institute of Scientific and Technical Information of China (English)

    ZHAI Ji-liang; LIN Jin; JIN Jin; QIAN Wen-wei; WENG Xi-sheng

    2011-01-01

    Background Severe acetabular bone deficiency is a major challenge in acetabular revision surgery. Most cases require reconstruction of the acetabulum with bone grafting and a reinforcement device. The purpose of this study was to evaluate the results of this procedure for severe acetabular bone deficiency in acetabular revision surgery.Methods This study involved 12 patients (2 males and 10 females) with severe acetabular bone defects who underwent implantation of a reinforcement device (ring or cage) and bone grafting between February 2003 and October 2008. Using the Paprosky classification, 2 cases were Paprosky ⅡC, 6 were ⅢA, and 4 were ⅢB. The mean age at the time of surgery was 63.0 years (range, 46-78 years). During revision surgery, a reinforcement ring was implanted in 6patients, and a cage in 6 patients. The clinical and radiographic results were evaluated retrospectively. The mean duration of follow-up was 37 months (range, 9-71 months).Results The average Harris Hip Score improved from 35.2 preoperatively to 82.9 at the time of the final follow-up visit.The results were excellent in 8 hips (66.7%), good in 2 (16.7%), and fair in 2 (16.7%). Osteolysis was found in 1 case, but did not worsen. Three patients had yellow wound effusion, with healing after administration of dressing changes,debridement, and antibiotics. Dislocation occurred in a 62-year-old woman. Closed reduction was performed, and dislocation did not recur. There was no evidence of intraoperative acetabular fracture, nerve injury, ectopic ossification,aseptic loosening, or infection.Conclusion Reconstruction with a reinforcement device and bone grafting is an effective approach to the treatment of acetabular bone deficiency in acetabular revision surgery, given proper indications and technique.

  6. Computerized tomography in evaluation of decreased acetabular and femoral anteversion

    International Nuclear Information System (INIS)

    Computerized tomography has received a new importance. It has been shown that decreased anteversion of femur and acetabulum, when both have decreased angles, are causing pain and osteoarthritis of the hip joint. Operative treatment should be performed before osteoarthritis develops. Exact measurements therefore are necessary. The investigation should be performed in prone position to have the pelvis lying in a defined and normal position. Femoral torsion is measured between the transverse axis of the knee and the femoral neck. The transverse axis for measurement of the femoral anteversion is defined by a rectangular line to the sagittal plane. For evaluation of the femoral anteversion in total the angle of the condyles has to be added to the femoral neck angle when the knee is found in internal rotation. Acetabular anteversion should be measured at the level where the femoral head is still in full contact and congruence with the anterior margin of the acetabulum. (orig.)

  7. Radiologic analysis of femoral acetabular impingement: from radiography to MRI

    Energy Technology Data Exchange (ETDEWEB)

    Dwek, Jerry R. [University of California at San Diego, Department of Radiology, Rady Children' s Hospital and Health Center, San Diego, CA (United States); San Diego Imaging, San Diego, CA (United States); Monazzam, Shafagh [Rady Children' s Hospital and Health Center, Department of Orthopedics, San Diego, CA (United States); Chung, Christine B. [University of California at San Diego, Department of Radiology, San Diego, CA (United States)

    2013-03-15

    Femoral acetabular impingement is a set of morphologic abnormalities that are considered to be a major cause of degenerative disease in the hip joint. Early changes are already present in adolescence when it is the pediatric radiologist who must assess current damage with the aim of averting progression to more severe and debilitating osteoarthritis. A multimodality approach is used for diagnosis, that includes conventional radiography and CT to assess the osseous structures. MR arthrography is the primary advanced imaging modality for assessment of morphologic changes as well as injuries of the labrum and articular cartilage. Details of radiologic imaging are offered to guide the radiologist and provide an avenue for the accurate description of the osseous and articular alterations and injury. (orig.)

  8. Three-dimensional computed tomography analysis of non-osteoarthritic adult acetabular dysplasia

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hiroshi; Matsuno, Takeo; Hirayama, Teruhisa; Tanino, Hiromasa; Yamanaka, Yasuhiro [Asahikawa Medical College, Department of Orthopaedic Surgery, Asahikawa (Japan); Minami, Akio [Hokkaido University School of Medicine, Department of Orthopaedic Surgery, Sapporo (Japan)

    2009-02-15

    Little data exists on the original morphology of acetabular dysplasia obtained from patients without radiographic advanced osteoarthritic changes. The aim of this study was to investigate the distribution and degree of acetabular dysplasia in a large number of patients showing no advanced degenerative changes using three-dimensional computed tomography (3DCT). Eighty-four dysplastic hips in 55 consecutive patients were studied. All 84 hips were in pre- or early osteoarthritis without radiographic evidence of joint space narrowing, formation of osteophytes or cysts, or deformity of femoral heads. The mean age at the time of CT scan was 35 years (range 15-64 years). 3D images were reconstructed and analyzed using recent computer imaging software (INTAGE Realia and Volume Player). Deficiency types and degrees of acetabular dysplasia were precisely evaluated using these computer software. The average Harris hip score at CT scans was 82 points. Twenty-two hips (26%) were classified as anterior deficiency, 17 hips (20%) as posterior deficiency, and 45 hips (54%) as lateral deficiency. No significant difference was found in the Harris hip score among these groups. The analysis of various measurements indicated wide variations. There was a significant correlation between the Harris hip score and the acetabular coverage (p < 0.001). Our results indicated wide variety of deficiency type and degree of acetabular dysplasia. Hips with greater acetabular coverage tended to have a higher Harris hip score. (orig.)

  9. Patient-specific acetabular shape modelling: comparison among sphere, ellipsoid and conchoid parameterisations.

    Science.gov (United States)

    Cerveri, Pietro; Manzotti, Alfonso; Baroni, Guido

    2014-04-01

    The shape of the human acetabular cup was commonly represented as a hemisphere, but different geometries and patient-specific shapes have been recently proposed in the literature. Our aim was to test the limits of the sphericity assumption by comparing three different parameterisations, namely the sphere, the ellipsoid and the rotational conchoid. Models of hip surfaces, reconstructed from CT scans taken from Caucasian race cadavers and patients, were automatically processed to extract the acetabular surface. Two separate analyses were carried out on the overall acetabular shape, including both the acetabular fossa and the lunate surface (case A) and acetabular cup represented by the lunate surface only (case B). Nonlinear gradient-based and evolutionary computation approaches were implemented for the fitting process. Minor differences from the three idealised geometries were detected (median values of the fitting errors different from both the ellipsoid (p difference was detected between the ellipsoid and the conchoid for case A. Significance of the difference between ellipsoid and sphere (p difference was detected between the ellipsoid and the conchoid. In conclusion, we synthesise that the morphology of the overall acetabular cup can be parameterised both with an ellipsoid shape and with a conchoid shape as well with superior quality than the simple sphere. Differently, if one considers just the lunate surface, better fitting results are expected when using the ellipsoid. PMID:22789071

  10. The significance of evaluating the craniolateral acetabular rim for hip dysplasia

    International Nuclear Information System (INIS)

    The weight-bearing part of the canine hip is its dorsocraniolateral portion. On the radiograph the configuration of the craniolateral acetabular rim is important for evaluation of hip dysplasia. Changes in formation of this area should be differentiated from artefacts due to malpositioning. When the pelvis is tilted dorsally, the cranial acetabular rim is superimposed on the cranioventral acetabular contour and the acetabular roof. The craniolateral contour then seems to be missing. The contours of a ventrally tilted pelvis do not overlap, but it is difficult to discern the craniolateral rim. The reference points for Norberg-Olsson's measurements are difficult to choose in both cases and the angles may vary up to 10 degrees. A symmetrically positioned pelvis shows one point of reference for Norberg-Olsson's measurement where the cranial acetabular contour, the cranioventral margin and the acetabular roof intersect. Therefore poor positioning of the pelvis for radiographic evaluation of hip dysplasia should be avoided when using Norberg-Olsson's measurements

  11. Utilizing of the metallurgical slag for production of cementless concrete mixtures

    Directory of Open Access Journals (Sweden)

    D. Baricová

    2012-10-01

    Full Text Available In process of pig iron, steel and cast iron production besides main product, also secondary products are formed, that have character of secondary raw materials and industrial wastes. The most abundant secondary product originating in the metallurgical process is furnace slag. Total amount of accured slag, also its chemical, mineralogical, physical – chemical properties and similarity with natural stones predestinate its utilisation in different fields of industry. The contribution deals with production of cementless concrete mixtures, where the main parts were formed by blast furnace granulated slag grinded and different gravel slag from blast furnace, oxygen converter and electric arc furnace. As activators of solidification different kinds of water glass were tested.

  12. Second-Generation Versus First-Generation Cementless Tapered Wedge Femoral Stems.

    Science.gov (United States)

    Pierce, Todd P; Jauregui, Julio J; Kapadia, Bhaveen H; Elmallah, Randa K; Cherian, Jeffrey J; Harwin, Steven F; Mont, Michael A

    2015-09-01

    Clinical outcomes of a new second-generation proximally coated, tapered wedge cementless stem were compared with those of its predecessor regarding (1) all-cause implant survivorship; (2) objective and subjective outcomes; (3) complications; and (4) radiographic features. Patients who underwent a primary total hip arthroplasty with the second-generation stem (68 hips) were compared with those who received the first-generation stem (136 hips) at a mean follow-up of 3.5 years. Although the first-generation stem was designed in the traditional manner, the second-generation stem was shortened to accommodate all surgical approaches and designed using a computed tomography scan-based database to enhance fit. The second-generation stem had survivorship, functional, and subjective outcomes similar to those of the first-generation stem. PMID:26375526

  13. Surgical Outcome of Acetabular Fracture Using Trochanteric Flip Osteotomy

    Directory of Open Access Journals (Sweden)

    Espandar R

    2012-01-01

    Full Text Available Background: One of the difficulties in acetabulum surgery is appropriate exposure of the site of surgery. Trochanteric flip osteotomy is one of the surgical methods for superoposterior and posterior acetabulum exposure. However, due to possible complications some surgeons prefer to avoid this procedure. This study was undertaken to determine the outcome of surgical treatment of acetabular fracture using trochanteric flip osteotomy. Methods : In this prospective cohort study, 14 patients with acetabular fracture who had been admitted in Imam Khomeini Hospital in Tehran, Iran, during 2003-2006 underwent trochanteric flip osteotomy. The patients were followed for at least one year post-surgically. Demographics, radiologic findings, intensity of pain using visual analogue scale (VAS, Harris hip score (HHS, force of hip abductors and complications were noted. Data analysis was performed using SPSS ver. 13.Results : The mean HHS was 82.5 (55-95. Heterotopic ossification was observed in three patients. There were no cases of postoperative infection or nonunion. Only two patients showed displacement of osteotomized fragments. Reduction was anatomic in 10 patients. In one patient, the force of hip abductors was three-fifth. The mean hip pain was 3.4 based on VAS. There were no cases of femoral head osteonecrosis. With respect to HHS, the final hip status was excellent and good in four and six patients, respectively. Three patients had fair and only one patient had poor condition.Conclusion: It seems that trochanteric flip osteotomy has much fewer complications in comparison to other methods justifying its use in such cases.

  14. Analysis of cementless implants using interface nonlinear friction--experimental and finite element studies.

    Science.gov (United States)

    Dammak, M; Shirazi-Adl, A; Zukor, D J

    1997-02-01

    Measured interface nonlinear friction properties are used to develop models to study the short-term fixation response of smooth- and porous-surfaced posts, bone screws, and plates fixed with and without posts/screws. Experimental studies are carried out to validate the model predictions and identify the relative role of posts and screws in fixation of a plate on a polyurethane block under symmetric/eccentric axial compression loads. The idealized Coulomb's friction is also used for the sake of comparison. The incorporation of measured nonlinear, rather than the idealized Coulomb, friction is essential to compute realistic results. For plate fixation, the experimental and finite element results show that the screw fixation yields the stiffest response followed by the smooth- and then porous-coated post fixation. For example, under 1000 N eccentric axial compression, the edge of the plate opposite the loaded edge is measured to lift by 1147 +/- 72, 244 +/- 38, or 112 +/- 28 microns, respectively, for the cases with no fixation, with smooth-surfaced posts, or with screws. The corresponding models predict, respectively, values of 1538, 347, or 259 microns and also 556 microns for the plate fixed with porous coated posts. The satisfactory agreement between numerical and experimental results confirms the importance of proper interface modelling for the analysis of posts, screws, and complex fixation systems. This becomes further evident when considering cementless implants in which the bone-implant interface exhibits relatively large displacements as the maximum resistance force is reached. The developed models can be used to investigate the post-operative short-term stability of various cementless implant designs. PMID:9001932

  15. A biodegradable gentamicin-hydroxyapatite-coating for infection prophylaxis in cementless hip prostheses

    Directory of Open Access Journals (Sweden)

    D Neut

    2015-01-01

    Full Text Available A degradable, poly (lactic-co-glycolic acid (PLGA, gentamicin-loaded prophylactic coating for hydroxyapatite (HA-coated cementless hip prostheses is developed with similar antibacterial efficacy as offered by gentamicin-loaded cements for fixing traditional, cemented prostheses in bone. We describe the development pathway, from in vitro investigation of antibiotic release and antibacterial properties of this PLGA-gentamicin-HA-coating in different in vitro models to an evaluation of its efficacy in preventing implant-related infection in rabbits. Bone in-growth in the absence and presence of the coating was investigated in a canine model. The PLGA-gentamicin-HA-coating showed high-burst release, with antibacterial efficacy in agar-assays completely disappearing after 4 days, minimising risk of inducing antibiotic resistance. Gentamicin-sensitive and gentamicin-resistant staphylococci were killed by the antibiotic-loaded coating, in a simulated prosthesis-related interfacial gap. PLGA-gentamicin-HA-coatings prevented growth of bioluminescent staphylococci around a miniature-stem mounted in bacterially contaminated agar, as observed using bio-optical imaging. PLGA-gentamicin-HA-coated pins inserted in bacterially contaminated medullary canals in rabbits caused a statistically significant reduction in infection rates compared to HA-coated pins without gentamicin. Bone ingrowth to PLGA-gentamicin-HA-coated pins, in condylar defects of Beagle dogs was not impaired by the presence of the degradable, gentamicin-loaded coating. In conclusion, the PLGA-gentamicin-HA-coating constitutes an effective strategy for infection prophylaxis in cementless prostheses.

  16. Cranial acetabular retroversion is common in developmental dysplasia of the hip as assessed by the weight bearing position

    DEFF Research Database (Denmark)

    Troelsen, Anders; Mikkelsen, Lone Rømer; Jacobsen, Steffen;

    2010-01-01

    The appearance of acetabular version differs between the supine and weight bearing positions in developmental dysplasia of the hip. Weight bearing radiographic evaluation has been recommended to ensure the best coherence between symptoms, functional appearance, and hip deformities. Previous...... prevalence estimates of acetabular retroversion in dysplastic hips have been established in radiographs recorded with the patient supine and with inclusion only if pelvic tilt met standardized criteria. We assessed the prevalence and the extent of acetabular retroversion in dysplastic hip joints in weight...

  17. Increasing thickness and fibrosis of the cartilage in acetabular dysplasia: a rabbit model research

    Institute of Scientific and Technical Information of China (English)

    LI Tian-you; MA Rui-xue

    2010-01-01

    Background The order and mechanism of pathological changes in acetabular dysplasia are still unclear. This study investigated cartilage changes in rabbit acetabular dysplasia models at different ages.Methods Twenty-seven 1-month-old New Zealand rabbits underwent cast immobilization of the left hind limb in knee extension. Serial acetabular dysplasia models were established by assessment of the acetabular index and Sharp's angle on radiographs. The thickness of the acetabular cartilage was measured under a microscope, and fibrosis was observed. Ultrastructural changes were investigated with scanning electron microscopy and transmission electron microscopy. The messenger RNA expression of collagen Ⅰ and Ⅱ, β1 integrin, and caspase-9 were measured by real-time fluorescence quantitative polymerase chain reaction.Results In an immature group of rabbits, the acetabular index of the treated hip increased with animal growth. The cartilage on the brim of the left acetabulum was significantly thicker than that on the right side. The collagen fibrils on the surface of the cartilage became gross, and the chondrocytes in the enlargement layer underwent necrosis. In a mature group of rabbits, the left Sharp's angle increased in the rabbits with 6-week casting. The cartilage on the brim of the left acetabulum underwent fibrosis. The chondrocytes were weakly stained, and the number of lysosomes was much larger than normal. The messenger RNA expression of collagen Ⅰ and Ⅱ, β1 integrin, and caspase-9 in the cartilage differed significantly at different ages.Conclusions Increasing thickness followed by fibrosis may be the order of pathological cartilage changes in acetabular dysplasia, with changes in ultrastructure and collagen expression contributing to the process.

  18. Estudo da estabilidade dos componentes na artroplastia total do joelho sem cimento Study on implant stability in cementless total knee arthroplasty

    Directory of Open Access Journals (Sweden)

    Luís Eduardo Passarelli Tírico

    2012-01-01

    Full Text Available OBJETIVO: Comparar dois métodos de avaliação da estabilidade dos componentes tibial e femoral nas artroplastias de joelho não cimentadas com plataforma rotatória. MÉTODOS: Para isso foram avaliados 20 pacientes (20 joelhos através de uma análise de radiografias dinâmicas com intensificador de imagem e manobras de estresse em varo e valgo, que foram comparadas com radiografias estáticas em frente e perfil dos joelhos, analisadas por dois cirurgiões experientes, cegos um em relação ao outro. RESULTADOS: Os resultados das análises estáticas e dinâmicas foram comparados e demonstraram forte correlação estatística (pObjetives: Determine the stability of tibial and femoral components of 20 cementless knee arthroplasties with rotating platform. METHODS: The 20 patients (20 knees underwent an analysis of dynamic radiographs with an image amplifier and maneuvers of varus and valgus which were compared to static frontal and lateral radiographs of the knees and analyzed by two experienced surgeons in a double-blind way. RESULTS: We could observe in this study that both methods showed very similar results for the stability of the tibial and femoral components (p<0,001 using the Kappa method for comparison. CONCLUSION: The tibial component was more unstable in relation to the femoral component in both static and dynamic studies. Level of evidence IV, Case Series.

  19. Validation of a simple radiographic method to determine variations in pelvic and acetabular cup sagittal plane alignment after total hip arthroplasty

    Energy Technology Data Exchange (ETDEWEB)

    Shon, Won Yong; Hur, Chang Yong; Jajodia, Nirmal [Korea University College of Medicine, Guro Hospital, Department of Orthopedics, Seoul (Korea); Gupta, Siddhartha; Biswal, Sandeep; Hong, Suk Joo; Myung, Jae Sung [Korea University College of Medicine, Guro Hospital, Department of Radiology, Seoul (Korea)

    2008-12-15

    Orientation of acetabular component, influenced by pelvic tilt, body position, and individual variations affects the outcome following total hip arthroplasty (THA). Currently available methods of evaluation are either imprecise or require advanced image processing. We analyzed intersubject and intrasubject variability of pelvic tilt, measured by sagittal sacral tilt (ST) and its relationship with acetabular component tilt (AT) by using a simple method based on standard radiographs. ST was measured on lateral radiographs of pelvis including lumbosacral spine obtained in supine, sitting, standing, and lateral decubitus position for 40 asymptomatic THA patients and compared to computed tomography (CT) data obtained in supine position. AT was measured on lateral radiographs (measured acetabular tilt: MAT) in each position and compared to measurement of AT on CT and an indirectly calculated AT (CAT). Mean ST changed from supine to sitting, standing, and lateral decubitus positions as follows: 26.5 {+-} 15.5 (range 4.6-73.4 ), 8.4{+-}6.2 (range 0.6-24.5 ), and 13.4{+-}8.4 (range 0.1-24.2 ; p<0.0001, p=0.002, p=0.006). The MAT on radiographs was not significantly different from the MAT measured on CT (p=0.002) and the CAT (p=0.06). There is a good correlation between change in ST and MAT in sagittal plane (r=0.93). Measurement of ST on radiographs is a simple and reliable method to track changes in pelvic tilt in different body positions. There is significant intersubject and intrasubject variation of ST and MAT with postural changes and it may explain causes of impingement or instability following THA, which could not be previously explained. (orig.)

  20. Validation of a simple radiographic method to determine variations in pelvic and acetabular cup sagittal plane alignment after total hip arthroplasty

    International Nuclear Information System (INIS)

    Orientation of acetabular component, influenced by pelvic tilt, body position, and individual variations affects the outcome following total hip arthroplasty (THA). Currently available methods of evaluation are either imprecise or require advanced image processing. We analyzed intersubject and intrasubject variability of pelvic tilt, measured by sagittal sacral tilt (ST) and its relationship with acetabular component tilt (AT) by using a simple method based on standard radiographs. ST was measured on lateral radiographs of pelvis including lumbosacral spine obtained in supine, sitting, standing, and lateral decubitus position for 40 asymptomatic THA patients and compared to computed tomography (CT) data obtained in supine position. AT was measured on lateral radiographs (measured acetabular tilt: MAT) in each position and compared to measurement of AT on CT and an indirectly calculated AT (CAT). Mean ST changed from supine to sitting, standing, and lateral decubitus positions as follows: 26.5 ± 15.5 (range 4.6-73.4 ), 8.4±6.2 (range 0.6-24.5 ), and 13.4±8.4 (range 0.1-24.2 ; p<0.0001, p=0.002, p=0.006). The MAT on radiographs was not significantly different from the MAT measured on CT (p=0.002) and the CAT (p=0.06). There is a good correlation between change in ST and MAT in sagittal plane (r=0.93). Measurement of ST on radiographs is a simple and reliable method to track changes in pelvic tilt in different body positions. There is significant intersubject and intrasubject variation of ST and MAT with postural changes and it may explain causes of impingement or instability following THA, which could not be previously explained. (orig.)

  1. Acetabular rim and surface segmentation for hip surgery planning and dysplasia evaluation

    Science.gov (United States)

    Tan, Sovira; Yao, Jianhua; Yao, Lawrence; Summers, Ronald M.; Ward, Michael M.

    2008-03-01

    Knowledge of the acetabular rim and surface can be invaluable for hip surgery planning and dysplasia evaluation. The acetabular rim can also be used as a landmark for registration purposes. At the present time acetabular features are mostly extracted manually at great cost of time and human labor. Using a recent level set algorithm that can evolve on the surface of a 3D object represented by a triangular mesh we automatically extracted rims and surfaces of acetabulae. The level set is guided by curvature features on the mesh. It can segment portions of a surface that are bounded by a line of extremal curvature (ridgeline or crestline). The rim of the acetabulum is such an extremal curvature line. Our material consists of eight hemi-pelvis surfaces. The algorithm is initiated by putting a small circle (level set seed) at the center of the acetabular surface. Because this surface distinctively has the form of a cup we were able to use the Shape Index feature to automatically extract an approximate center. The circle then expands and deforms so as to take the shape of the acetabular rim. The results were visually inspected. Only minor errors were detected. The algorithm also proved to be robust. Seed placement was satisfactory for the eight hemi-pelvis surfaces without changing any parameters. For the level set evolution we were able to use a single set of parameters for seven out of eight surfaces.

  2. Minimum ten-year follow-up of acetabular fracture fixation from the Irish tertiary referral centre.

    LENUS (Irish Health Repository)

    Magill, Paul

    2012-04-01

    Successful outcome from acetabular fracture fixation is multi-factorial. Long-term results are not frequently reported. Pooling such data from high output centres will help progress acetabular fixation. This paper presents the first ten-year data from the Irish tertiary referral centre.

  3. Cemented total hip arthroplasty with impacted morcellized bone-grafts to restore acetabular bone defects in congenital hip dysplasia.

    NARCIS (Netherlands)

    Bolder, S.B.T.; Melenhorst, J.; Gardeniers, J.W.M.; Slooff, T.J.J.H.; Veth, R.P.H.; Schreurs, B.W.

    2001-01-01

    We evaluated the results of 27 acetabular reconstructions in 21 patients with secondary osteoarthritis resulting from congenital dysplasia of the hip in which the acetabular bone defects were restored with impacted morcellized bone-grafts in combination with a cemented cup. At an average follow-up o

  4. Quantification of clearance and creep in acetabular wear measurements

    Science.gov (United States)

    Gregory, Thomas; Vandenbussche, Eric

    2016-01-01

    Background This study aimed to measure femoral head penetration before occurrence of real wear, and to quantify the portions attributable respectively to clearance and plastic deformations in various acetabular designs. Methods We analyzed CT scans from 15 patients at ‘day five’ after total hip arthroplasty (THA). All patients received Exafit® femoral stems and 28 mm heads: 5 patients had cemented Durasul® all-PE cups, 5 patients had un-cemented Allofit® metal-backed cups, and 5 patients had un-cemented Stafit® dual-mobility cups. We also analyzed CT scans of samples of the three head-cup combinations to compare in vivo and in vitro measurements. Results The mean femoral head penetration measured on ‘day five’ was lower for all-PE cups (0.196 mm) than for metal-backed cups (0.551 mm) and dual-mobility cups (0.634 mm). Conclusions The present study indicates that isolated measurements of femoral head penetration include 0.15–0.46 mm of radial clearance and 0.05–0.27 mm of creep, and confirms that the majority of so-called bedding-in observed in the first post-operative months is not entirely due to wear. PMID:27162781

  5. Results of Chiari pelvic osteotomy for acetabular dysplasia in adults

    International Nuclear Information System (INIS)

    In an attempt to determine indications of Chiari pelvic osteotomy in acetabular dysplasia, postoperative outcome of hip joint (64 joints) was examined on the basis of findings of bone scintigraphy. The subjects were 61 patients with osteoarthrosis of hip joint who underwent preoperative bone scintigraphy. The follow-up period ranged from 2 years to 9 years and 7 months with a mean of 4 years and 9 months. According to X-ray findings, 37 osteoarthrosis joints were staged as early and 27 as progressive. Preoperative bone scintigraphic findings fell into three: (I) normal or slight hot type (33 joints), (II) hot type at the weighting part (16 joints), and (III) double hot type in the weighting part and inside part (15 joints). None of the patients had severe surgical complications such as deep-seated infection, neuroparalysis and pseudojoint. According to the clinical staging for hip joint function, 7 (47%) of 64 joints were judged as poor after osteotomy, belonging to type III. Deterioration of osteoarthrosis was seen in 11 joints (41%) on X-ray films. Of these, 9 had type III. In conclusion, Chiari pelvic osteotomy should not be indicated when type III is shown on bone scintigrams. (N.K.)

  6. Magnetic resonance arthrography of the acetabular labral lesion

    International Nuclear Information System (INIS)

    Magnetic resonance arthrography (MRA) is a reliable diagnostic method with high sensitivity and accuracy for acetabular labral lesion in the hip joint. This paper describes the present state and task of the method mainly based on authors' experience. Subjects are 18 patients with the lesion, whose 10 joints have dysplastic shelf (Sharp angle >45 degrees). Enhanced T1-weighted, and 3D T2 as well, MRA is conducted with the machine Signa Excite 3.0 T (GE), rapidly after injection in the joint cavity of 10-20 mL of gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) 100 times-diluted by iopamidol. Abnormal MRA findings involve the labral morphology of circular edge, flatness, irregular contour and shrink/disappearance, and the image of high brightness in parenchyma, invasion of the contrast medium there, and discontinuousness between the shelf edge and labrum. The lesion predominantly exists at anterior and superior portion on the labrum and the images of ganglion and synovial cyst suggest the existence of labral tear. Normal variants can give a part of the abnormal MRA findings above, and thus who require the differential diagnosis for the lesion. Education of MRA is a task for general orthopedists. (R.T.)

  7. Biomechanical evaluation of adjunctive cerclage wire fixation for the prevention of periprosthetic femur fractures using cementless press-fit total hip replacement.

    Science.gov (United States)

    Christopher, Scott A; Kim, Stanley E; Roe, Simon; Pozzi, Antonio

    2016-08-01

    Periprosthetic femoral fractures are a common complication associated with cementless press-fit total hip arthroplasty. The use of prophylactic cerclage wire fixation has been advocated to reduce this complication. The objective of this study was to evaluate whether a double loop cerclage wire, used as adjunctive fixation, increased the peak torsional load to failure in femora implanted with press-fit cementless stems. Peak torsional load to failure was compared between femora without adjunctive fixation and femora receiving a 1 mm double loop cerclage wire placed proximally to the lesser trochanter. Femora treated with adjunctive cerclage wire fixation failed at 20% greater peak torque (P = 0.0001). In conclusion, a double loop cerclage wire may aid in the prevention of periprosthetic fractures associated with press-fit cementless femoral stems. PMID:27387718

  8. Ultrasound versus Magnetic Resonance Arthrography in Acetabular Labral Tear Diagnostics: A Prospective Comparison in 20 Dysplastic Hips

    Energy Technology Data Exchange (ETDEWEB)

    Troelsen, A.; Jacobsen, S.; Bolvig, L.; Gelineck, J.; Roemer, L.; Soeballe, K. [Orthopedic Research Unit and Dept. of Radiology, Univ. Hospital of Aarhus, A arhus (Denmark)

    2007-11-15

    Background: Acetabular labral tears are highly associated with hip dysplasia. Magnetic resonance arthrography (MR arthrography) is the expensive and time-consuming contemporary gold-standard method in the radiological assessment of acetabular labral tears. Purpose: To assess the diagnostic ability of noninvasive ultrasound (US) examination compared to MR arthrography in diagnosing acetabular labral tears in dysplastic hip joints. Material and Methods: The study compared US examination and MR arthrography diagnosis of labral tears in 20 consecutively referred dysplastic hip joints. Results: The ability to diagnose acetabular labral tears upon US examination was calculated: sensitivity 44%, specificity 75%, positive predictive value 88%, and negative predictive value 25%. Conclusion: The ability of US examination in diagnosing acetabular labral tears is not yet good enough. The technique is still to be developed, and more experience, especially with the interpretation of US examinations, is needed.

  9. Micromotion of cemented and uncemented femoral components.

    Science.gov (United States)

    Burke, D W; O'Connor, D O; Zalenski, E B; Jasty, M; Harris, W H

    1991-01-01

    We evaluated the initial stability of cemented and uncemented femoral components within the femoral canals of cadaver femurs during simulated single limb stance and stair climbing. Both types were very stable in simulated single limb stance (maximum micromotion of 42 microns for cemented and 30 microns for uncemented components). However, in simulated stair climbing, the cemented components were much more stable than the uncemented components (76 microns as against 280 microns). There was also greater variation in the stability of uncemented components in simulated stair climbing, with two of the seven components moving 200 microns or more. Future implant designs should aim to improve the initial stability of cementless femoral components under torsional loads; this should improve the chances of bony ingrowth. PMID:1991771

  10. Acetabular stress fractures in military endurance athletes and recruits: incidence and MRI and scintigraphic findings

    International Nuclear Information System (INIS)

    Objective: To evaluate the incidence and the MRI and scintigraphic appearance of acetabular stress (fatigue) fractures in military endurance athletes and recruits. Design and patients: One hundred and seventy-eight active duty military endurance trainees with a history of activity-related hip pain were evaluated by both MRI and bone scan over a 2-year period. Patients in the study ranged in age from 17 to 45 years. They had hip pain related to activity and had plain radiographs of the hip and pelvis that were interpreted as normal or equivocal. The study was originally designed to evaluate the MRI and scintigraphic appearance of femoral neck stress fractures. Patients had scintigraphy and a limited MRI examination (coronal imaging only) within 48 h of the bone scan. Twelve patients demonstrated imaging findings compatible with acetabular stress fractures. Results: Stress fractures are common in endurance athletes and in military populations; however, stress fracture of the acetabulum is uncommon. Twelve of 178 patients (6.7%) in our study had imaging findings consistent with acetabular stress fractures. Two patterns were identified. Seven of the 12 (58%) patients had acetabular roof stress fractures. In this group, two cases of bilateral acetabular roof stress fractures were identified, one with a synchronous tensile sided femoral neck stress fracture. The remaining five of 12 (42%) patients had anterior column stress fractures, rarely occurring in isolation, and almost always occurring with inferior pubic ramus stress fracture (4 of 5, or 80%). One case of bilateral anterior column stress fractures was identified without additional sites of injury. Conclusions: Stress fractures are commonplace in military populations, especially endurance trainees. Acetabular stress fractures are rare and therefore unrecognized, but do occur and may be a cause for activity-related hip pain in a small percentage of military endurance athletes and recruits. (orig.)

  11. Quantifying the contribution of pincer deformity to femoro-acetabular impingement using 3D computerised tomography

    Energy Technology Data Exchange (ETDEWEB)

    Dandachli, Wael; Najefi, Ali; Iranpour, Farhad; Lenihan, Jonathan; Hart, Alister; Cobb, Justin [Imperial College London, Charing Cross Hospital, Department of Orthopaedic Surgery, London (United Kingdom)

    2012-10-15

    To provide a simple, reliable method for the three-dimensional quantification of pincer-type hip deformity. Computerised tomography scans of 16 normal female hips and 15 female hips with clinical femoro-acetabular impingement (FAI) and radiographic signs of pincer secondary to acetabular protrusio were analysed. After orientating the pelvis in the anterior pelvic plane, the acetabular centre was determined, and the ratios of its coordinates to the corresponding pelvic dimensions were calculated. Acetabular coverage of the femoral head and centre-edge angles were also measured for the two groups. In hips with a pincer, the hip was medialised by 37 % (p = 0.03), more proximal by 5 % (p = 0.05) and more posterior by 9 % (p = 0.03) compared with the normal hips. Coverage of the femoral head in protrusio hips was significantly greater than normal (average 71 % vs 82 %, p = 0.0001). Both the lateral centre-edge angle and the combined anterior-posterior centre-edge angle were greater in protrusio hips than in the normal ones (48 vs 37 , p < 0.001; and 216 vs 176 , p < 0.0001 respectively). Displacement in acetabular protrusio occurs in all planes. This CT-based method allows for the accurate and standardised quantification of the extent of displacement, as well as 3D measurement of femoral head coverage. In the adult female population, a combined centre-edge angle of over 190 suggests an acetabulum that is too deep and a potential cause of symptoms of femoro-acetabular impingement. Conversely, an acetabulum that has a combined centre-edge angle of less than 190 may be considered to be of normal depth, and therefore not contributing a pincer to FAI should it occur. (orig.)

  12. Quantifying the contribution of pincer deformity to femoro-acetabular impingement using 3D computerised tomography

    International Nuclear Information System (INIS)

    To provide a simple, reliable method for the three-dimensional quantification of pincer-type hip deformity. Computerised tomography scans of 16 normal female hips and 15 female hips with clinical femoro-acetabular impingement (FAI) and radiographic signs of pincer secondary to acetabular protrusio were analysed. After orientating the pelvis in the anterior pelvic plane, the acetabular centre was determined, and the ratios of its coordinates to the corresponding pelvic dimensions were calculated. Acetabular coverage of the femoral head and centre-edge angles were also measured for the two groups. In hips with a pincer, the hip was medialised by 37 % (p = 0.03), more proximal by 5 % (p = 0.05) and more posterior by 9 % (p = 0.03) compared with the normal hips. Coverage of the femoral head in protrusio hips was significantly greater than normal (average 71 % vs 82 %, p = 0.0001). Both the lateral centre-edge angle and the combined anterior-posterior centre-edge angle were greater in protrusio hips than in the normal ones (48 vs 37 , p < 0.001; and 216 vs 176 , p < 0.0001 respectively). Displacement in acetabular protrusio occurs in all planes. This CT-based method allows for the accurate and standardised quantification of the extent of displacement, as well as 3D measurement of femoral head coverage. In the adult female population, a combined centre-edge angle of over 190 suggests an acetabulum that is too deep and a potential cause of symptoms of femoro-acetabular impingement. Conversely, an acetabulum that has a combined centre-edge angle of less than 190 may be considered to be of normal depth, and therefore not contributing a pincer to FAI should it occur. (orig.)

  13. Primary stability recognition of the newly designed cementless femoral stem using digital signal processing.

    Science.gov (United States)

    Baharuddin, Mohd Yusof; Salleh, Sh-Hussain; Hamedi, Mahyar; Zulkifly, Ahmad Hafiz; Lee, Muhammad Hisyam; Mohd Noor, Alias; Harris, Arief Ruhullah A; Abdul Majid, Norazman

    2014-01-01

    Stress shielding and micromotion are two major issues which determine the success of newly designed cementless femoral stems. The correlation of experimental validation with finite element analysis (FEA) is commonly used to evaluate the stress distribution and fixation stability of the stem within the femoral canal. This paper focused on the applications of feature extraction and pattern recognition using support vector machine (SVM) to determine the primary stability of the implant. We measured strain with triaxial rosette at the metaphyseal region and micromotion with linear variable direct transducer proximally and distally using composite femora. The root mean squares technique is used to feed the classifier which provides maximum likelihood estimation of amplitude, and radial basis function is used as the kernel parameter which mapped the datasets into separable hyperplanes. The results showed 100% pattern recognition accuracy using SVM for both strain and micromotion. This indicates that DSP could be applied in determining the femoral stem primary stability with high pattern recognition accuracy in biomechanical testing. PMID:24800230

  14. Primary Stability Recognition of the Newly Designed Cementless Femoral Stem Using Digital Signal Processing

    Directory of Open Access Journals (Sweden)

    Mohd Yusof Baharuddin

    2014-01-01

    Full Text Available Stress shielding and micromotion are two major issues which determine the success of newly designed cementless femoral stems. The correlation of experimental validation with finite element analysis (FEA is commonly used to evaluate the stress distribution and fixation stability of the stem within the femoral canal. This paper focused on the applications of feature extraction and pattern recognition using support vector machine (SVM to determine the primary stability of the implant. We measured strain with triaxial rosette at the metaphyseal region and micromotion with linear variable direct transducer proximally and distally using composite femora. The root mean squares technique is used to feed the classifier which provides maximum likelihood estimation of amplitude, and radial basis function is used as the kernel parameter which mapped the datasets into separable hyperplanes. The results showed 100% pattern recognition accuracy using SVM for both strain and micromotion. This indicates that DSP could be applied in determining the femoral stem primary stability with high pattern recognition accuracy in biomechanical testing.

  15. Primary Stability Recognition of the Newly Designed Cementless Femoral Stem Using Digital Signal Processing

    Science.gov (United States)

    Salleh, Sh-Hussain; Hamedi, Mahyar; Zulkifly, Ahmad Hafiz; Lee, Muhammad Hisyam; Mohd Noor, Alias; Harris, Arief Ruhullah A.; Abdul Majid, Norazman

    2014-01-01

    Stress shielding and micromotion are two major issues which determine the success of newly designed cementless femoral stems. The correlation of experimental validation with finite element analysis (FEA) is commonly used to evaluate the stress distribution and fixation stability of the stem within the femoral canal. This paper focused on the applications of feature extraction and pattern recognition using support vector machine (SVM) to determine the primary stability of the implant. We measured strain with triaxial rosette at the metaphyseal region and micromotion with linear variable direct transducer proximally and distally using composite femora. The root mean squares technique is used to feed the classifier which provides maximum likelihood estimation of amplitude, and radial basis function is used as the kernel parameter which mapped the datasets into separable hyperplanes. The results showed 100% pattern recognition accuracy using SVM for both strain and micromotion. This indicates that DSP could be applied in determining the femoral stem primary stability with high pattern recognition accuracy in biomechanical testing. PMID:24800230

  16. Failure of Polyethylene Inlays in Cementless Total Hip Arthroplasty: A Retrieval Analysis

    Directory of Open Access Journals (Sweden)

    Ulrike Mueller

    2016-01-01

    Full Text Available A retrieval analysis has been performed on 50 polyethylene inlays of cementless screw ring implants (Mecring, Mecron, Berlin, Germany to investigate the failure mechanism of this specific open cup hip arthroplasty design that has shown a high clinical failure rate. Design-specific damage modes like rim creep, collar fatigue, and backside wear were assessed. Furthermore, the inlays were measured using a CMM to determine deformation. In 90% backside wear was observed and collar fatigue occurred in 68% of the cases. Rim creep was present in 38% of the polyethylene inlays. In 90% of the cases the cup opening diameter was 32.1 mm or less and 46% had a diameter less than 32 mm. It seems that creep and deformation of the polyethylene leads to a reduced diameter at the cup opening and consequently decreased clearance. To avoid this type of failure, polyethylene inlays should be supported at the back by the cup to reduce the risk of ongoing creep deformation.

  17. Entrapment of the acetabular labrum following reduction of traumatic hip dislocation in a child

    International Nuclear Information System (INIS)

    In traumatic hip dislocation, concentric reduction can be prevented by various causes. Soft-tissue interposition, such as entrapment of the acetabular labrum, is a rare but important cause of failed reduction of a hip. Early diagnosis of incomplete reduction due to interposition of soft tissue is important, because delayed treatment is associated with a greater incidence of avascular necrosis of the femoral head and early onset of osteoarthritis. This report describes a case of acetabular labral entrapment following reduction of traumatic hip dislocation in a child. The importance of CT and MRI in arriving at an early diagnosis is emphasized. (orig.)

  18. Acetabular anteversion is associated with gluteal tendinopathy at MRI

    Energy Technology Data Exchange (ETDEWEB)

    Moulton, Kyle M. [University of Saskatchewan, Department of Medical Imaging, Saskatoon, SK (Canada); Royal University Hospital, Department of Medical Imaging, Saskatoon, SK (Canada); Aly, Abdel-Rahman [University of Saskatchewan, Department of Physical Medicine and Rehabilitation, Saskatoon, SK (Canada); Rajasekaran, Sathish [Health Pointe - Pain, Spine and Sport Medicine, Edmonton, AB (Canada); Shepel, Michael; Obaid, Haron [University of Saskatchewan, Department of Medical Imaging, Saskatoon, SK (Canada)

    2015-01-15

    Gluteal tendinopathy and greater trochanteric pain syndrome (GTPS) remain incompletely understood despite their pervasiveness in clinical practice. To date, no study has analyzed the morphometric characteristics of the hip on magnetic resonance imaging (MRI) that may predispose to gluteal tendinopathy. This study aimed to evaluate whether acetabular anteversion (AA), femoral neck anteversion (FNA), and femoral neck-shaft angle (FNSA) are associated with MRI features of gluteal tendinopathy. A total of 203 MRI examinations of the hip met our inclusion and exclusion criteria. A single blinded investigator measured AA, FNA, and FNSA according to validated MRI techniques. Two blinded subspecialty-trained musculoskeletal radiologists then independently evaluated the presence of gluteal tendinosis, trochanteric bursitis, and subgluteal bursitis. Statistical analysis was performed using a one-way analysis of variance (ANOVA; post-hoc Tukey's range test). At MRI, 57 patients had gluteal tendinosis with or without bursitis, 26 had isolated trochanteric bursitis, and 11 had isolated subgluteal bursitis. AA was significantly (p = 0.01) increased in patients with MRI evidence of gluteal tendinosis with or without bursitis [mean: 18.4 , 95 % confidence interval (CI): 17.2 -19.6 ] compared with normal controls (mean: 15.7 , 95 % CI: 14.7 -16.8 ). Similarly, AA was significantly (p = 0.04) increased in patients with isolated trochanteric bursitis (mean: 18.8 , 95 % CI: 16.2 -21.6 ). No association was found between FNA or FNSA and the presence of gluteal tendinopathy. Interobserver agreement for the presence and categorization of gluteal tendinopathy was very good (kappa = 0.859, 95 % CI: 0.815-0.903). Our MRI study suggests that there is an association between increased AA and gluteal tendinopathy, which supports a growing body of evidence implicating abnormal biomechanics in the development of this condition. (orig.)

  19. A multicenter approach evaluating the impact of vitamin E-blended polyethylene in cementless total hip replacement

    Directory of Open Access Journals (Sweden)

    Marcus Jäger

    2014-04-01

    Full Text Available Since polyethylene is one of the most frequently used biomaterials as a liner in total hip arthroplasty, strong efforts have been made to improve design and material properties over the last 50 years. Antioxidants seems to be a promising alternative to further increase durability and reduce polyethylene wear in long term. As of yet, only in vitro results are available. While they are promising, there is yet no clinical evidence that the new material shows these advantages in vivo. To answer the question if vitamin-E enhanced ultra-high molecular weight polyethylene (UHMWPE is able to improve long-term survivorship of cementless total hip arthroplasty we initiated a randomized long-term multicenter trial. Designed as a superiority study, the oxidation index assessed in retrieval analyses of explanted liners was chosen as primary parameter. Radiographic results (wear rate, osteolysis, radiolucency and functional outcome (Harris Hip Scores, University of California-Los Angeles, Hip Disability and Osteoarthritis Outcome Score, Visual Analogue Scale will serve as secondary parameters. Patients with the indication for a cementless total hip arthroplasty will be asked to participate in the study and will be randomized to either receive a standard hip replacement with a highly cross-linked UHMWPE-X liner or a highly cross-linked vitamin-E supplemented UHMWPE-XE liner. The follow-up will be 15 years, with evaluation after 5, 10 and 15 years. The controlled randomized study has been designed to determine if Vitamin-E supplemented highly cross-linked polyethylene liners are superior to standard XLPE liners in cementless total hip arthroplasty. While several studies have been started to evaluate the influence of vitamin-E, most of them evaluate wear rates and functional results. The approach used for this multicenter study, to analyze the oxidation status of retrieved implants, should make it possible to directly evaluate the ageing process and development

  20. Wear analysis by applying a pin-disc configuration to phemoral head and acetabular cup Análisis del desgaste de la articulación cabeza femoral–copa acetabular mediante simulación experimental con máquina perno-disco

    Directory of Open Access Journals (Sweden)

    Beltrán-Fernandez Juan Alfonso

    2008-07-01

    Full Text Available This work determines a prosthetic hip system’s life-span, focusing on a Mexican phenotype. The total sliding equivalent distance for the system was determined, as well as the loading regime under which the femoral component and the acetabular cup were subjected in normal operating conditions. An experimental tribology essay was then performed to simulate the wearing of the components in a Pin over Disc machine. This assay (for which the test specimens were manufactured in medical grade stainless steel AISI-ASTM 316L for the femoral component and high density polyethylene for the acetabular cup was aimed at simulating wear conditions involved in 10 years of continuous operation. A numerical simulation of operational conditions (using the finite element method was performedIn for establishing assay loading conditions to accurately determine where the loads should be applied. The tribology assay led to quantifying the volumetric loss of materials for the system being analysed. It can be concluded that the methodology proposed in this work for estimating the life-span of a prosthetic hip system was valid and accurate by comparing the results with those found in the literature. A statistical validation of the proposed method is plaaned for the future. Key words: Design life; femoral component; acetabular cup; Mexican phenotype; pin-disc configuration.Este trabajo presenta un estudio que permite establecer la vida útil esperada de un sistema prostético de cadera para el caso del fenotipo mexicano. En primera instancia se determinó la distancia total equivalente de deslizamiento y las condiciones de carga entre el componente femoral y la copa acetabular bajo condiciones normales de carga. Posteriormente, se desarrolló una simulación experimental para la realización de un ensayo tribológico en una máquina de desgaste del tipo Perno sobre Disco (Pin on Disk, POD. Este ensayo sometió al conjunto fabricado en acero inoxidable AISI

  1. 3.0 T conventional hip MR and hip MR arthrography for the acetabular labral tears confirmed by arthroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Chun-Yan [Department of Radiology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Wang, Jian-Quan [Department of Sports Medicine, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191,PR China (China); Zheng, Zhuo-Zhao, E-mail: zzhuozhao@aliyun.com [Department of Radiology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Ren, A.-Hong [Department of Radiology, Beijing Daxing Hospital, 26 West Huangcun Road, Daxing District, Beijing 102600 (China)

    2014-10-15

    Highlights: • MR is the preferred imaging modality for diagnosing acetabular labral tears. • The diagnostic performance of MR arthrography are superior than conventional hip MR. • The hip MR arthrography is recommended for diagnosing acetabular labral lesions. - Abstract: Objective: To evaluate the value of hip MR for diagnosing acetabular labrum tears, and to further compare the diagnostic performances of conventional MR with MR arthrography in acetabular labrum tears. Methods: 90 patients undergoing both hip MR examination and subsequent hip arthroscopy were retrospectively evaluated. Of these patients, 34 accepted both conventional MR and MR arthrography; while the other 56 only underwent conventional MR examination. All hip MR images were independently reviewed by two radiologists, and further compared with the results of hip arthroscopy. Results: 59 of 90 patients were confirmed with acetabular labral tears by hip arthroscopy and 31 without tears. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of conventional MR for evaluating the acetabular labral tears were 61.0%, 77.4%, 83.7% and 51.1% (radiologist A), and 66.1%, 74.2%, 82.9% and 53.4% (radiologist B), respectively, with good consistency between the two observers (K = 0.645). The sensitivity, specificity, PPV and NPV of MR arthrography for assessing the acetabular labral tears were 90.5%, 84.6%, 90.5% and 84.6% (radiologist A), and 95.2%, 84.6%, 90.9% and 91.7% (radiologist B), respectively, with excellent good consistency between the two observers (K = 0.810). The sensitivity and NPV of MR arthrography for diagnosing the acetabular labral tears were significantly higher than those of conventional MR (both P < 0.05). Conclusion: Hip MR arthrography is a reliable evaluation modality for diagnosing the acetabular labral tears, and its diagnostic performance is superior to that of conventional MR at 3.0 T.

  2. Percutaneous screw placement in acetabular posterior column surgery: gender differences in implant positioning.

    Science.gov (United States)

    Dienstknecht, Thomas; Müller, Michael; Sellei, Richard; Nerlich, Michael; Pfeifer, Christian; Krutsch, Werner; Fuechtmeier, Bernd; Berner, Arne

    2014-04-01

    Percutaneous reduction and periarticular screw implantation techniques have been successfully introduced in acetabular surgery. Image guided navigation techniques might be beneficial in increasing accuracy. However, a thorough understanding of standard values is needed to oversee pitfalls. This cadaver study was designed to identify reliable angulation values for screw implantation in the posterior acetabular column and to provide knowledge of the bony thickness for the periarticular corridor. Gender differences were specifically addressed. 27 embalmed cadaveric hemipelvic specimens (13 male, 14 female) were used. After soft-tissue removal posterior column acetabular screw placement was conducted by one experienced orthopaedic trauma surgeon under visibility. Radiographic verification of ideal screw placement was followed by radiographic assessment in three standard views and angulation values were assessed. Through bony dissection the maximal periarticular canal width was assessed. Various angulation values with regard to anatomical landmarks could be determined in the anteroposterior radiograph, as well as in the iliac oblique and the obturator oblique view. Gender differences were significant for all reference points with the pubic rami involved. The minimal canal width was 1.1cm in female and 1.6 cm in male specimen. The findings provide standard values for safe passages in percutaneous posterior column acetabular surgery. Gender differences have to be taken in consideration when planning the drill corridor. By adherence to standard values, screw placement can be performed safely. PMID:24182644

  3. Free iliac crest grafts with periosteum for treatment of old acetabular defects

    Institute of Scientific and Technical Information of China (English)

    ZHAO De-wei; SUN Qiang; WANG Ben-jie; CUI Da-ping

    2006-01-01

    Objective: To inquire into the therapeutic effectiveness of free iliac crest grafts with periosteum on old acetabular defects.Methods: From February 1996 to June 2005, 9 patients were treated with free iliac crest grafts with periosteum to reconstruct old acetabular defects. There were 7 males and 2 females and the average age was 41.3 years. The acetabular defects were caused by traffic accidents in 6 cases and fall injury in 3 cases. The time from injury to treatment was 4-13 months and averaged 8 months. Intraoperatively we firstly removed the acetabular fracture fragments of the posterior wall. The femoral head was then reducted. Bone graft was harvested from the iliac crest with periosteum, which was sculpted with a rongeur to conform to the defect. The concave (iliac fossa) side of the graft was placed toward the femoral head. The graft was securedly fixed by two to three leg screws.Results: Postoperative syndrome was not found in any of the cases. Harris' score system showed that the score raised from 32. 3 points preoperatively to 81 points postoperatively. The hip function was evaluated as excellent in 3 cases, good in 4 cases and fair in 2 cases.Conclusions: Although this procedure could not exactly reproduce the anatomy of the hip joint, it enables to restore the posterior stability, provide bone-stock for the hip joints and prevent dislocation of the femoral head.

  4. Relationship between developmental dislocation of the hip in infant and acetabular dysplasia at skeletal maturity.

    Science.gov (United States)

    Okano, Kunihiko; Yamaguchi, Kazumasa; Ninomiya, Yoshikazu; Matsubayashi, Shohei; Aoyagi, Kiyoshi; Osaki, Makoto; Enomoto, Hiroshi; Takahashi, Katsuro

    2015-01-01

    Previous reports demonstrated 8-60% patients treated for developmental dislocation of hip (DDH) in infancy have residual acetabular dysplasia (AD) at skeletal maturity. AD patients reportedly exhibit abnormal morphology of the pelvis, high rates of comorbid spinal congenital anomalies and high bone mineral density. These physical findings suggest that AD patients have genetic background. We examined the percentage of AD patients with hip pain at skeletal maturity having a history of DDH in infancy and the correlation between the severity of AD at skeletal maturity and history of DDH treatment to investigate the relationship between AD and DDH.A total of 245 patients were radiographically examined for any history of DDH treatment in infancy. The study included 226 women and 19 men with a mean age at examination of 40.7 years (range 17-59 years).Eighty-eight patients (36%) had a history of DDH treatment (DDH group) and the remaining 157 patients (64%) had no history of DDH treatment (non-DDH group). The average age was lower and acetabular angle was larger in the DDH group. There was a significant increasing trend of the percentage of DDH patients associated with the severity of AD classified with CE, acetabular angle, and acetabular roof angle.Our data suggest that there are several AD patients without a history of DDH in Japan, and AD in patients without a history of DDH has different characteristics from AD in patients with a history of DDH. PMID:25569642

  5. Microstructure and mechanical properties of cementless construction materials from thermal engineering wastes

    International Nuclear Information System (INIS)

    In order to solve environment problems of ceramics industry new compositions of materials were developed from three types of porcelain production tails – fired wastes (FW), unfired wastes (UW) and wastewater treatment plant sludge (WTPS) – as the main raw materials of new compositions of cementless building materials. The binder material used here was lime production waste (LPW), i.e., incompletely burned lime. The uniaxial compressive strength of the new materials containing 15 wt% of LPW at one year of age increased up to 14.2 MPa and the materials with 5% LPW content increased up to 8.6 MPa, exceeding the specifications of Brazilian standards for hollow concrete blocks. The water absorption (WA) coefficient of different compositions at the age of 28 days ranged from 17.9 to 24.6%, but this does not affect the values of the water resistance coefficient (0.71–0.85). X-ray diffraction and scanning electron microscopy analyses indicated that the strength of the new materials increases due to the synthesis of amorphous and crystalline compounds. The feasibility of the new materials based on the use of four types of industrial wastes for the production of new building materials with high mechanical properties, which meet the requirements of national standards. - Highlights: • New construction material from three types of Porcelain industry wastes. • Lime production waste was used as binder material. • Uniaxial resistance strength at the age of one year reached 14 MPa. • Structure formation processes were determined by XRD, SEM and EDS methods. • Utilization of industrial wastes has high economical and environment efficiency

  6. A Femur-Implant Model for the Prediction of Bone Remodeling Behavior Induced by Cementless Stem

    Institute of Scientific and Technical Information of China (English)

    He Gong; Lingyan Kong; Rui Zhang; Juan Fang; Meisheng Zhao

    2013-01-01

    Bone remodeling simulation is an effective tool for the prediction of long-term effect of implant on the bone tissue,as well as the selection of an appropriate implant in terms of architecture and material.In this paper,a finite element model of proximal femur was develop.ed to simulate the structures of internal trabecular and cortical bones by incorporating quantitative bone functional adaptation theory with finite element analysis.Cementless stems made of titanium,two types of Functionally Graded Material (FGM) and flexible 'iso-elastic' material as comparison were implanted in the structure of proximal femur respectively to simulate the bone remodeling behaviors of host bone.The distributions of bone density,von Mises stress,and interface shear stress were obtained.All the prosthetic stems had effects on the bone remodeling behaviors of proximal femur,but the degrees of stress shielding were different.The amount of bone loss caused by titanium implant was in agreement with the clinical observation.The FGM stems caused less bone loss than that of the titanium stem,in which FGM I stem (titanium richer at the top to more HAP/Col towards the bottom) could relieve stress shielding effectively,and the interface shear stresses were more evenly distributed in the model with FGM I stem in comparison with those in the models with FGM II (titanium and bioglass) and titanium stems.The numerical simulations in the present study provided theoretical basis for FGM as an appropriate material of femoral implant from a biomechanical point of view.The next steps are to fabricate FGM stem and to conduct animal experiments to investigate the effects of FGM stem on the remodeling behaviors using animal model.

  7. Wear and degradation of uhmwpe total hip replacement components

    OpenAIRE

    Kipping, Michael

    2009-01-01

    Long term (>2 years) failure of UHMWPE components in-vivo is predominantly caused by wear of the UHMWPE component. The surface properties of UHMWPE greatly influence the adhesive and abrasive mechanisms of wear that occur in the hip. However, there is not a clear understanding of how in-vivo wear mechanisms influence surface mechanical properties of UHMWPE. In addition, previous researchers have reported wear rates for Charnley UHMWPE acetabular components that vary considerably between pati...

  8. Tantalum acetabular augments in one-stage exchange of infected total hip arthroplasty: a case-control study.

    Science.gov (United States)

    Klatte, Till Orla; Kendoff, Daniel; Sabihi, Reza; Kamath, Atul F; Rueger, Johannes M; Gehrke, Thorsten

    2014-07-01

    During the one-stage exchange procedure for periprosthetic joint infection (PJI) after total hip arthroplasty (THA), acetabular defects challenge reconstructive options. Porous tantalum augments are an established tool for addressing acetabular destruction in aseptic cases, but their utility in septic exchange is unknown. This retrospective case-control study presents the initial results of tantalum augmentation during one-stage exchange for PJI. Primary endpoints were rates of re-infection and short-term complications associated with this technique. Study patients had no higher risk of re-infection with equivalent durability at early follow-up with a re-infection rate in both groups of 4%. In conclusion, tantalum augments are a viable option for addressing acetabular defects in one-stage exchange for septic THA. Further study is necessary to assess long-term durability when compared to traditional techniques for acetabular reconstruction. PMID:24559522

  9. Open reduction and internal fixation aided by intraoperative 3-dimensional imaging improved the articular reduction in 72 displaced acetabular fractures

    DEFF Research Database (Denmark)

    Eckardt, Henrik; Lind, Dennis; Toendevold, Erik

    2015-01-01

    Background and purpose - During acetabular fracture surgery, the acetabular roof is difficult to visualize with 2-dimensional fluoroscopic views. We assessed whether intraoperative 3-dimensional (3D) imaging can aid the surgeon to achieve better articular reduction and improve implant fixation....... Patients and methods - We operated on 72 acetabular fractures using intraoperative 3D imaging and compared the operative results, duration of surgery, and complications with those for 42 consecutive acetabular fracture operations conducted using conventional fluoroscopic imaging. Postoperative reduction...... was evaluated on reconstructed coronal and sagittal images of the acetabulum. Results - The fracture severity and patient characteristics were similar in the 2 groups. In the 3D group, 46 of 72 patients (0.6) had a perfect result after open reduction and internal fixation, and in the control group, 17...

  10. A novel technique for impaction bone grafting in acetabular reconstruction of revision total hip arthroplasty using an ex vivo compaction device

    International Nuclear Information System (INIS)

    Impaction bone grafting allows restoration of the acetabular bone stock in revision hip arthroplasty. The success of this technique depends largely on achieving adequate initial stability of the component. To obtain well-compacted, well-graded allograft aggregates, we developed an ex vivo compaction device to apply it in revision total hip arthroplasty on the acetabular side, and characterized mechanical properties and putative osteoconductivity of allograft aggregates. Morselized allograft bone chips were compacted ex vivo using the creep technique and subsequent impaction technique to form the bone aggregates. Impaction allograft reconstruction of the acetabulum using an ex vivo compaction device was performed on eight hips. The mechanical properties and three-dimensional micro-CT-based structural characteristics of the bone aggregates were investigated. In clinical practice, this technique offered good reproducibility in reconstructing the cavity and the segmental defects of the acetabulum, with no migration and no loosening of the component. In vitro analysis showed that the aggregates generated from 25 g fresh-frozen bone chips gained compression stiffness of 13.5-15.4 MPa under uniaxial consolidation strain. The recoil of the aggregates after compaction was 2.6-3.9%. The compression stiffness and the recoil did not differ significantly from those measured using a variety of proportions of large- and small-sized bone chips. Micro-CT-based structural analysis revealed average pore sizes of 268-299 μm and average throat diameter of pores in the bone aggregates of more than 100 μm. These sizes are desirable for osteoconduction, although large interconnected pores of more than 500 μm were detectable in association with the proportion of large-sized bone chips. Cement penetration into the aggregates was related to the proportion of large-sized bone chips. This study introduces the value of an ex vivo compaction device in bone graft compaction in clinical

  11. Massive heterotopic ossification associated with late deficits in posterior wall of acetabulum after failed acetabular fracture operation

    OpenAIRE

    Zhang, Yuntong; Xie, Yang; Xu, Shuogui; Zhang, Chuncai

    2013-01-01

    Background Heterotopic ossification is a common postoperative complication of acetabular fracture. However, functionally significant heterotopic ossification with associated late bone defects in the posterior wall of the acetabulum is rare and challenging to treat. When heterotopic ossification is a late complication of failed acetabular fracture operation, it is disabling and may only be treated by THA. THA is highly susceptible to premature failure in young and active patients and may requi...

  12. Performance of Non-Cemented, Hemispherical, Rim-Fit, Hydroxyapatite Coated Acetabular Component.

    Science.gov (United States)

    John, Thomas K; Ghosh, Gaurav; Ranawat, Chitranjan S; Ranawat, Amar S; Meftah, Morteza

    2015-12-01

    The purpose of this study was to assess the durability of a non-cemented, hemispherical rim-fit, hydroxyapatite coated cup with a highly cross-linked polyethylene in 223 total hip arthroplasties. At 6-years follow-up (range, 5-9), there were no cup revisions for osteolysis or loosening. Radiologic evidence of osseointegration was based on presence of Stress Induced Reactive Cancellous Bone and radial trabeculae, seen in 47% and 93% of cups, respectively; both were most prevalent in Zone 1. There was no interference demarcation in any zones. Two cups were revised (0.9%): one for dislocation and another for infection. The Kaplan-Meier survivorship for cup revision for any failure (infection, dislocation) was 99% and for mechanical failure (osteolysis, loosening) was 100%. This design has excellent safety, efficacy and durability. PMID:26235521

  13. Development of Imageless Computer Navigation for Acetabular Component Position in Total Hip Replacement

    OpenAIRE

    Dorr, Lawrence D.; Hishiki, Yuji; Wan, Zhinian; Newton, Deanne; Yun, Andrew

    2005-01-01

    The purpose of this study was to develop an imageless (without preoperative computerized tomography (CT) scans or intraoperative fluoroscopy) computer navigation system for total hip replacement. One-hundred and ninety-five hips were operated with imageless computer navigation. Eighty-five hips were operated prior to obtaining precise results, with precision refined in the subsequent 110 hips. Computer accuracy for cup-adjusted anteversion was achieved in 100% of the final 40 hips, and for ad...

  14. Femoro-acetabular impingement and hip pain with conventionally normal x-rays.

    LENUS (Irish Health Repository)

    Baker, J F

    2010-06-01

    There has in recent years been a fundamental change in the understanding of hip pain in the young adult and hip pain without plain radiographic findings of arthritis. Pain in these groups has long represented a diagnostic and therapeutic challenge. With new appreciation of hip biomechanics, pathological processes and the arrival of modern imaging modalities we now have a greater understanding of non-arthritic hip pathology. One of the commonest yet least well recognized \\'new\\' diagnoses around the hip is femoro-acetabular impingement (FAI). FAI is a developmental condition of the hip joint that is associated with abnormal anatomical configuration and thus joint mechanics on either the femoral or acetabular sides or both. It is hypothesized to have a variety of precipitants and may ultimately lead to labral and chondral injury and what has previously been referred to as \\'primary\\' or \\'idiopathic\\' hip osteoarthritis.

  15. The preliminary application of magnetic resonance arthrography in the diagnosis of acetabular labrale tears

    International Nuclear Information System (INIS)

    Objective: To investigate the application value of MR arthrography (MRA) in the diagnosis of acetabular lab ral tears. Methods: Fifteen patients with a high degree of suspected acetabular lab ral tears received fluoroscope-guided injection of the contrast media into the hip joint (hip arthrography) and fat-saturated spin-echo T1-weighted images were obtained in the coronal, sagittal, oblique-axial and radial planes. Hip arthroscopy was performed on 12 of them. Results: Lab ral tears which were diagnosed in 11 patients by hip MRA were confirmed at hip arthroscopy. One patient showed no MRA indication of lab ral tear, also showed normal on arthroscopy. Tear in the anterior-superior quadrant 10 cases of 12 joints (12/13), posterior-superior quadrant 1 case of a joint (1/13). In 11 patients who underwent arthroscopy, hip MRA diagnosed 3 (3/13) joints labrale tears in coronal planes, 10 (10/13) joints in sagittal planes and 13 (13/13) labrale tears in axial-oblique and radial planes. In 15 patients with 20 hip joints, 5 cases 6 joints (6/20) with normal acetabular sublabral sulcus were performed. Conclusions: MR arthrography of hip is a reliable method in the diagnosis of acetabular labrale tears. Scanning method should be included fat-saturated spin-echo T1-weighted images in sagittal and oblique-axial planes or sagittal plus radial planes. The diagnosis of torn posterior-inferior quadrant should pay attention to the existence of a normal variation. (authors)

  16. Three-Dimensional CT Modeling Versus Traditional Radiology Techniques in Treatment of Acetabular Fractures

    OpenAIRE

    Brown, George A.; Firoozbakhsh, Keikhosrow; Gehlert, Rick J

    2001-01-01

    Recently, the authors have used the computer generated three-dimensional (3-D) CT moving images for preoperative planning and screw/pin insertion in more than 28 cases involving plate and screw fixation of complex acetabular fractures. The authors also used stereolithography (wax or plastic 3-D model of bony anatomy) to develop a computer-generated "clip on" interpositioning template for accurate placement of plate and screws. Application of these new technologies gives the surgeon precise in...

  17. Osteonecrosis and femoro-acetabular impingement: sequelae of developmental dysplasia of the hip

    OpenAIRE

    Cheung, Jason Pui Yin; Chow, Wang; To, Michael

    2012-01-01

    A 2-year-old girl with developmental dysplasia of the right hip underwent open reduction and capsulorrhaphy via the anterior approach with hip spica casting in an internally rotated position. During her 26 years of follow-up, she was found to have osteonecrosis and subsequently cam-type femoro-acetabular impingement at 28 years of age. She was treated with surgical dislocation of the hip and osteochondroplasty to recreate the normal contour of the head and neck offset.

  18. The place of computerized axial tomography in the evaluation of acetabular fractures

    OpenAIRE

    Asik, Mehmet; Akman, Senol; Taser, Omer; Aritamur, Ayhan

    2004-01-01

    Besides the importance of standard AP and Judet s 45° iliac and obturator pelvic views, CAT has proved to be very useful in the evaluation of the fractures of the acetabulum. Of 96 patients with acetabular fractures, who applied to the Orthopaedics and Traumatology Department, Istanbul Medical Faculty, Istanbul University between 1987 and 1991 in addition to conventional radiography, CAT investigation was done in 32 patients for whom it was considered necessary. The results of both convention...

  19. Custom-made locked plating for acetabular fracture: a pilot study in 24 consecutive cases.

    Science.gov (United States)

    Xu, Meng; Zhang, Li-Hai; Zhang, Ying-Ze; Zhang, Li-Cheng; He, Chun-Qing; Wang, Yan; Tang, Pei-Fu

    2014-07-01

    Clinical implementation of site-specific locking plates for acetabular fracture remains untested. Custom-made locking plates were manufactured using computer-aided design and computer-aided manufacture techniques for acetabular fractures to test this procedure. The 3-dimensional images constructed from computed tomography data of pelvises in patients with acetabular fractures were used for preoperative planning and to design the plates. Data for each plate were input into software for programming, and the generated code was transferred into a computerized numerical control digital milling machine for manufacturing. These plates were clinically implemented, and the implementation parameters, reduction quality, and Postel Merle d'Aubigné score were evaluated. Forty-nine custom-made locking plates were manufactured for 24 unilateral acetabular fractures. The manufacturing process for the plates averaged 6.9±2.2 days. Processing the plates delayed operations by 2.6±1.3 days in one-third of the cases. Plate contouring was avoided in 48 plates. The plates had anatomical shapes, excellently matching reduced bone surface. The screws locked with the obtained plates avoided intra-articular penetration and provided secure fixation that allowed early out-of-bed rehabilitation. No indications of implant failures or observations of screw back-outs were observed during follow-up. The clinical application of such plates is associated with the avoidance of plate contouring, low risk of intra-articular penetration, early out-of-bed rehabilitation, and a low rate of implant failure. Implementing such plates in clinical practice is worthy of further investigation, with a focus on selecting patient population and minimizing the time required for and cost of plate manufacturing. PMID:24992064

  20. The role of experience level in radiographic evaluation of femoroacetabular impingement and acetabular dysplasia

    OpenAIRE

    Schottel, Patrick C.; Park, Caroline; Chang, Anthony; Knutson, Zakary; Ranawat, Anil S.

    2014-01-01

    Accurate radiographic interpretation is essential for properly diagnosing the etiology of pre-arthritic hip pain such as femoroacetabular impingement (FAI) and acetabular dysplasia (AD); however, radiographic interpretation can be significantly influenced by the observer’s experience level. This study assesses the accuracy and inter- and intraobserver reliability in the radiographic evaluation of FAI and AD based on experience level. Fifty-five patients diagnosed with FAI, AD or normal hip mo...

  1. The Effect of an Acetabular Labral Tear, Repair, Resection, and Reconstruction on the Hip Fluid Seal

    OpenAIRE

    Nepple, Jeffrey J.; Campbell, Kevin J.; Wijdicks, Coen A.; Jansson, Kyle; Dornan, Grant; LaPrade, Robert F.; Philippon, Marc J.

    2014-01-01

    Objectives: The acetabular labrum is theorized to have an important role in the normal function of the hip through the hip fluid seal. The hip fluid seal functions to create intra-articular fluid pressurization and stability to distractive forces. Yet, the effect of a labral tear or partial labral resection, and interventions including labral repair and labral reconstruction, on the hip fluid seal remain to be defined. The purpose of the current study was to characterize the hip fluid seal, i...

  2. The effect of femoro-acetabular impingement on the kinematics and kinetics of the hip joint

    OpenAIRE

    Alshameeri, Zeiad; Khanduja, Vikas

    2014-01-01

    Gait analysis is an objective tool that has been used to assess and monitor treatment for many musculoskeletal conditions. Recently, it has been used to assess the impact of femoro-acetabular impingement (FAI) on the hip and lower limb movements. There have been a fairly limited number of studies published so far reporting unexpected and inconsistent results, which calls for more research to be conducted in this arena. In the light of the limited data available, it has been challenging to rec...

  3. Surgical treatment of acetabular fractures: clinical and radiological results and its complications

    International Nuclear Information System (INIS)

    The objective of this work is to analyse a serie of consecutive cases of surigically treated acetabular fractures, evaluating middle-term clinical and radiological results. A retrospective analysis of clinical histories, surgical forms and X-rays was performed for 42 patients who underwent surgery in two centers (Instituto Nacional de Ortopedia y Traumatologia [INOT] and Banco de Protesis), from July 2001 through August 2007

  4. Zweymueller螺旋臼在成人先天性髋臼发育不良外科治疗中的应用%Primary study of application with Zweymuller cementless total hip arthroplasty for adult congenital acetabular dysplasia

    Institute of Scientific and Technical Information of China (English)

    熊道海; 曹力; 张克远; 田百超

    2006-01-01

    目的:初步探讨Zweymueller型髋臼假体治疗成人先天性髋臼发育不良继发髋关节骨性关节炎的有效性.方法: 应用Zweymueller型人工全髋关节假体,对27例30个成人先天性髋关节发育不良继发髋关节骨性关节炎患者行全髋关节置换(THR).术前Harris评分最高56分,最低24分,平均42.6分.结果: 所有患者髋关节疼痛完全消失,关节活动度增加,髋臼假体稳定.Harris评分最高98分,最低78分,平均90分.X线评价无松动征像, 髋臼假体位置良好.结论: 特殊设计的Zweymueller型人工全髋关节假体髋臼重建初期稳定,手术不需大块植骨和骨水泥,初期随访效果满意.

  5. Stable Fixation of a Cementless, Proximally Coated, Double Wedged, Double Tapered Femoral Stem in Total Hip Arthroplasty

    DEFF Research Database (Denmark)

    Nebergall, Audrey K; Rolfson, Ola; Rubash, Harry E;

    2016-01-01

    BACKGROUND: The objective of this 5-year prospective study of 51 hips was to assess migration of a cementless tapered femoral stem using radiostereometric analysis (RSA), plain radiographs (radiolucencies), and patient-reported outcome measures (PROMs). METHODS: Forty-seven patients (51 hips......) agreed to participate in this prospective RSA study. All patients received a Taperloc stem. Tantalum beads were inserted into the femoral bone surrounding the stem to measure migration using RSA. RSA films, plain radiograph, and PROM follow-up were obtained immediately after surgery, 6 months, 1, 2, 3...... year remain stable at 5 years. RSA was the most sensitive method of detection for stems at greater risk for potential future failure. This report adds contributions to the positive results associated with this type of fixation. The results at 5 years showed excellent midterm survivorship in this cohort...

  6. Rapid Hip Osteoarthritis Development in a Patient with Anterior Acetabular Cyst with Sagittal Alignment Change

    Directory of Open Access Journals (Sweden)

    Yasuhiro Homma

    2014-01-01

    Full Text Available Rapidly destructive coxarthrosis (RDC is rare and develops unusual clinical course. Recent studies suggest multiple possible mechanisms of the development of RDC. However the exact mechanism of RDC is still not clear. The difficulty of the study on RDC is attributed to its rareness and the fact that the data before the onset of RDC is normally unavailable. In this report, we presented the patient having the radiographic data before the onset who had rapid osteoarthritis (OA development after contralateral THA, which meets the current criteria of RDC. We thought that the increased posterior tilt of the pelvis after THA reinforced the stress concentration at pre-existed anterior acetabular cyst, thereby the destruction of the cyst was occurred. As a result the rapid OA was developed. We think that there is the case of rapid osteoarthritis developing due to alternating load concentration by posterior pelvic tilt on preexisting anterior acetabular cyst such as our patient among the cases diagnosed as RDC without any identifiable etiology. The recognition of sagittal alignment changes and anterior acetabular cyst may play important role in prediction and prevention of the rapid hip osteoarthritis development similar to RDC.

  7. Iliac redirectional osteotomy of the acetabular without use of bony implant

    International Nuclear Information System (INIS)

    The objective is to value the results of an original redirectional acetabular osteotomy, devised by its senior author. We describe 20 patients with hip developmental dysplasia (14 females and 6 males). The surgical approach is similar to the original description for Salter's osteotomy. The ilium cut buy a gigli saw, is performed in a curved fashion along the bone's coronal plane starting in the greater sciatic notch directed toward the anterior inferior iliac spine. The acetabolum is displaced anterior, lateral and caudally and the osteotomy is fixed with k-wires or screws, according to bone volume and quality, without graft interposition. The patient is immobilized in a spica cast for four to six weeks. Solid bone union was documented in all patients at the six-week follow up. The mean acetabular index correction obtained was measured at six weeks (16 degrades) and at six months (13 degrades). Initial femoral epiphysis extrusion was 25% and there was none at the six-month follow up. At two year later developmental displasia was not documented. This iliac redirectional osteotomy appears as a safe procedure, providing stability and contact for bone union and assures an adequate correction of the pre operative acetabular index and femoral head extrusion. Besides, this technique avoids the risk of graft collapse as in the original Salter's osteotomy

  8. Porous surface replacement of the hip with chamfered-cylinder component.

    Science.gov (United States)

    Amstutz, H; Kilgus, D; Kabo, M; Dorey, F

    1988-01-01

    One hundred porous surface replacements (PSR) were performed in 92 patients (63 men and 29 women) with a mean age of 53 (range 17-76). Follow-up times range from 1 to 4 years, with 48 patients having a follow-up of at least 2 years. Preoperative diagnoses were osteoarthritis (OA) 63, osteonecrosis (ON) 13, dysplasia 9, rheumatoid-ankylosing spondylitis 6, and other 9. Seventeen hips had metal-backed acrylic-fixed THARIES acetabular sockets, nine hips had a porous cobalt chrome hemispheric beaded acetabular component with adjuvant fixation screws and externally protruding screw hubs, and 74 hips had a porous chamfered cylinder-design acetabulum. Pain relief had been immediate and more complete than with acrylic-fixed or biologic-ingrowth stem-type replacement with comparable walking and function improvements. There have been no major systemic complications, sepsis, or loosening. There have been two transient peroneal nerve palsies and three trochanteric fibrous unions. There have been three reoperations, one for subluxation, one for "metalosis" due to mesh pad loosening, and one femoral neck fracture. Examination of one removed femoral surface component which has been histologically sectioned revealed excellent (90%) bone in-growth. Circumferential progressive radiolucencies developed at the bone-cement interface by 1 year in all of the 17 acrylic-fixed acetabular components. Reaming or seating defects were noted in 25% of the ingrowth components on postoperative radiographs. Radiographic analysis of immediate postoperative films of the chamfered cylinder design acetabular components frequently demonstrated bone-component interface radiolucencies which represented component seating defects. These initial interface radiolucencies became progressively more narrow over the first six months postoperatively suggesting "healing" of the reamed bone-component interface with trabecular bone around the chamfered cylinder acetabular components. Partial healing of initial

  9. Bipolar hip arthroplasty as salvage treatment for loosening of the acetabular cup with significant bone defects

    Science.gov (United States)

    Ghanem, Mohamed; Glase, Almuth; Zajonz, Dirk; Roth, Andreas; Heyde, Christoph-E.; Josten, Christoph; von Salis-Soglio, Georg

    2016-01-01

    Introduction: Revision arthroplasty of the hip is becoming increasingly important in recent years. Early primary arthroplasty and longer life expectancy of the patients increases the number of revision surgery. Revision surgery of hip arthroplasty is major surgery for the patients, especially the elderly, with significant risks concerning the general condition of the patient. The aim of this work is to evaluate the outcome of bipolar hip arthroplasty as a salvage procedure for treatment of loosening of the acetabular cup with significant acetabular bone defects after total hip replacement (THR) in multi-morbid patients. Patients and methods: During the period from January 1st 2007 to December 31st 2011 19 revision hip surgeries were performed in 19 patients, in which the loosened acetabular cup was replaced by a bipolar head. The examined patient group consisted exclusively of female patients with an average of 75 years. The predominant diagnosis was “aseptic loosening” (84.2%). All patients in our study were multi-morbid. We decided to resort to bipolar hip arthroplasty due to the compromised general condition of patients and the major acetabular bone defects, which were confirmed intraoperatively. The postoperative follow-up ranged from 0.5 to 67 months (average 19.1 months). Results: Evaluation of the modified Harris Hip Score showed an overall improvement of the function of the hip joint after surgery of approximately 45%. Surgery was less time consuming and thus adequate for patients with significantly poor general health condition. We noticed different complications in a significant amount of patients (68.4%). The most common complication encountered was the proximal migration of the bipolar head. The rate of revision following the use of bipolar hip arthroplasty in revision surgery of the hip in our patients was high (21%). Despite the high number of complications reported in our study, we have noticed significant improvement of hip joint function as

  10. Bipolar hip arthroplasty as salvage treatment for loosening of the acetabular cup with significant bone defects

    Directory of Open Access Journals (Sweden)

    Ghanem, Mohamed

    2016-04-01

    Full Text Available Introduction: Revision arthroplasty of the hip is becoming increasingly important in recent years. Early primary arthroplasty and longer life expectancy of the patients increases the number of revision surgery. Revision surgery of hip arthroplasty is major surgery for the patients, especially the elderly, with significant risks concerning the general condition of the patient. The aim of this work is to evaluate the outcome of bipolar hip arthroplasty as a salvage procedure for treatment of loosening of the acetabular cup with significant acetabular bone defects after total hip replacement (THR in multi-morbid patients.Patients and methods: During the period from January 1 2007 to December 31 2011 19 revision hip surgeries were performed in , in which the loosened acetabular cup was replaced by a bipolar head. The examined patient group consisted exclusively of female patients with an average of 75 years. The predominant diagnosis was “aseptic loosening” (84.2%. All patients in our study were multi-morbid. We decided to resort to bipolar hip arthroplasty due to the compromised general condition of patients and the major acetabular bone defects, which were confirmed intraoperatively. The postoperative follow-up ranged from 0.5 to 67 months (average 19.1 months. Results: Evaluation of the modified Harris Hip Score showed an overall improvement of the function of the hip joint after surgery of approximately 45%.Surgery was less time consuming and thus adequate for patients with significantly poor general health condition. We noticed different complications in a significant amount of patients (68.4%. The most common complication encountered was the proximal migration of the bipolar head.The rate of revision following the use of bipolar hip arthroplasty in revision surgery of the hip in our patients was high (21%. Despite the high number of complications reported in our study, we have noticed significant improvement of hip joint function as well

  11. Exposure of the superior gluteal neurovascular bundle for the safe application of acetabular reinforcement cages in complex revisions.

    Science.gov (United States)

    Smitham, Peter J; Kosuge, Dennis; Howie, Donald W; Solomon, Lucian B

    2016-05-16

    The posterior approach to the hip is the most common extensile approach used, however exposure is limited superiorly by the superior gluteal neurovascular bundle (SGNB). The extra-pelvic course of the SGNB demonstrates variability between individuals, occasionally located only 1 cm from the acetabular rim. In complex acetabular reconstructions where the application of a reinforcement cage maybe required protecting the SGNB is challenging. The flanges of these cages are designed to sit on the ilium superior to the acetabular rim and to receive screws for fixation. The application of such cages may result in iatrogenic injury to the SGNB by way of forceful retraction or entrapment. We describe a technique that involves exposure and release of the SGNB such that the flanges of cage constructs may be safely applied. PMID:27079287

  12. Femoral anteversion is correlated with acetabular version and coverage in Asian women with anterior and global deficient subgroups of hip dysplasia: a CT study

    Energy Technology Data Exchange (ETDEWEB)

    Akiyama, Mio; Nakashima, Yasuharu; Fujii, Masanori; Sato, Taishi; Yamamoto, Takuaki; Mawatari, Taro; Motomura, Goro; Matsuda, Shuichi; Iwamoto, Yukihide [Kyushu University, Department of Orthopaedic Surgery, Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka (Japan)

    2012-11-15

    Morphological correlation between the acetabulum and femur at the hip joint is still controversial. We tested the hypothesis that femoral anteversion correlates with acetabular version and coverage in patients with developmental dysplasia of the hip (DDH). Using pelvic computed tomography (CT) images of 79 hips in 49 Asian women with DDH and 49 normal hips, we measured femoral anteversion, the axial and vertical acetabular version and the acetabular sector angle (ASA) to demarcate femoral head coverage. Depending on the location of the acetabular bone defect, dysplastic hips were divided into three subgroups: the anterior, global and posterior deficiency groups. We performed a comparative analysis between dysplastic and normal hips using the Wilcoxon rank sum test, and a relative analysis between femoral anteversion and acetabular measurements in dysplastic hips using Pearson's correlation coefficient. The amount of femoral anteversion in dysplastic hips was greater and more variable than in normal hips (p < 0.0001, p = 0.0277 respectively). Femoral anteversion in dysplastic hips correlated significantly with acetabular anteversion in the groups with anterior and global deficiency subgroups (p < 0.05, r = 0.2990, p < 0.05, r = 0.451 respectively), but not with the posterior deficiency subgroup. Femoral anteversion also correlated with vertical acetabular version. When acetabular coverage was examined, significant correlations were noted between femoral anteversion and anterior and superior coverage, but not with posterior coverage. These correlations were not observed in normal hips. Our results showed significantly greater and more variable femoral anteversion in DDH, and a significant correlation between femoral anteversion and acetabular version and coverage in DDH with anterior and global acetabular bone deficiency. (orig.)

  13. Femoral anteversion is correlated with acetabular version and coverage in Asian women with anterior and global deficient subgroups of hip dysplasia: a CT study

    International Nuclear Information System (INIS)

    Morphological correlation between the acetabulum and femur at the hip joint is still controversial. We tested the hypothesis that femoral anteversion correlates with acetabular version and coverage in patients with developmental dysplasia of the hip (DDH). Using pelvic computed tomography (CT) images of 79 hips in 49 Asian women with DDH and 49 normal hips, we measured femoral anteversion, the axial and vertical acetabular version and the acetabular sector angle (ASA) to demarcate femoral head coverage. Depending on the location of the acetabular bone defect, dysplastic hips were divided into three subgroups: the anterior, global and posterior deficiency groups. We performed a comparative analysis between dysplastic and normal hips using the Wilcoxon rank sum test, and a relative analysis between femoral anteversion and acetabular measurements in dysplastic hips using Pearson's correlation coefficient. The amount of femoral anteversion in dysplastic hips was greater and more variable than in normal hips (p < 0.0001, p = 0.0277 respectively). Femoral anteversion in dysplastic hips correlated significantly with acetabular anteversion in the groups with anterior and global deficiency subgroups (p < 0.05, r = 0.2990, p < 0.05, r = 0.451 respectively), but not with the posterior deficiency subgroup. Femoral anteversion also correlated with vertical acetabular version. When acetabular coverage was examined, significant correlations were noted between femoral anteversion and anterior and superior coverage, but not with posterior coverage. These correlations were not observed in normal hips. Our results showed significantly greater and more variable femoral anteversion in DDH, and a significant correlation between femoral anteversion and acetabular version and coverage in DDH with anterior and global acetabular bone deficiency. (orig.)

  14. Examination and treatment of a professional ballet dancer with a suspected acetabular labral tear: A case report.

    Science.gov (United States)

    Khoo-Summers, Lynnette; Bloom, Nancy J

    2015-08-01

    Dancers are at risk for developing groin pain that is due to acetabular labral tears. Although surgical management of labral tears has been reported extensively, conservative management has been poorly described. This case report describes the examination, diagnosis, and treatment of groin pain in a professional ballet dancer with a suspected acetabular labral tear. Treatment focused on decreasing anterior hip joint stresses and improving the precision of hip motion through correction of alignment and movement impairments noted during functional activities and dance. Successful outcomes included a reduction in pain and return to professional ballet dancing. PMID:25725589

  15. Acetabular morphometry and prevalence of hip dysplasia in the South Asian population

    Directory of Open Access Journals (Sweden)

    Masood Umer

    2009-07-01

    Full Text Available We carried out a cross-sectional study to measure the association of the seven acetabular parameters with pelvic morphometry and prevalence of hip dysplasia in our population. Convenience sampling was carried out and 250 consecutive patients who came to AKUH for intravenous pyelogram and had no complaints in the region of the hip joint were enrolled in the study. Post-micturition standardized plain antero-posterior pelvic radiographs of 250 asymptomatic adults (500 hip joints was studied. There were 136 males (54.4% and 114 females (45.6%. Mean age of our study population was 38 years (15-78 years. The average center edge angle was 35.5±6.6° standard deviation (SD, acetabular angle was 37.76±4.37°, depth to width ratio was 0.31±4.6°, roof obliquity was 10.6±6.2°, extrusion index was 0.1±5.8, lateral subluxation 8.9±2.7 mm, and peak to edge distance 17±3.98 mm. There was significant influence (p lower than  0.05 of age in all angles except depth to width ratio. A total of seven hip joints (1.4% were dysplastic with CE angle lower than 25° while four of the seven hips were severely dysplastic with CE angle  lower than 20°. In the dysplastic group there was significant correlation (p lower than 0.05 of CE angle with acetabular angle, depth to width ratio, extrusion index and peak to edge distance. Prevalence of hip dysplasia was found to be very low in our population. These results are consistent with the findings of studies carried out in other Asian countries.

  16. Inguinal Abnormalities in Male Patients with Acetabular Fractures Treated Using an Ilioinguinal Exposure

    Directory of Open Access Journals (Sweden)

    Reza Firoozabadi

    2015-09-01

    Full Text Available Purpose: Surgeons performing an ilioinguinal exposure for acetabular fracture surgery need to be aware of aberrant findings such as inguinal hernias and spermatic cord lesions. The purpose of this study is to report these occurrences in a clinical series of adult males undergoing acetabular fracture fixation and a series of adult male cadavers. The secondary aim is to characterize these abnormalities to aid surgeons in detecting these abnormalities preoperatively and coordinating a surgical plan with a general surgeon.Methods: Clinical study- Retrospective review of treated acetabular fractures through an ilioinguinal approach. Incidence of inguinal canal and spermatic cord abnormalities requiring general surgery consultation were identified. Corresponding CT scans were reviewed and radiographic characteristics of the spermatic cord abnormalities and/or hernias were noted.Cadaveric study- 18 male cadavers dissected bilaterally using an ilioinguinal exposure. The inguinal canal and the contents of the spermatic cord were identified and characterized.Results: Clinical Study- 5.7% (5/87 of patients had spermatic cord lesion and/or inguinal hernia requiring general surgical intervention. Preoperative pelvic CT scan review identified abnormalities noted intraoperatively in four of the five patients. Cord lipomas visualized as enlargements of the spermatic cord with homogeneous density. Hernias visualized as enlarged spermatic cords with heterogeneous density. Cadaver Study- 31% (11/36 of cadavers studied had spermatic cord and/or inguinal canal abnormalities. Average cord diameter in those with abnormalities was 24.9 mm (15-28 compared to 16 mm (11-22 in normal cords, which was statistically significant.Conclusion: The clinical and cadaveric findings emphasize the importance of understanding inguinal abnormalities and the value of detecting them preoperatively. The preoperative pelvic CT scans were highly sensitive in detecting inguinal abnormalities.

  17. What is the role of clinical tests and ultrasound in acetabular labral tear diagnostics?

    DEFF Research Database (Denmark)

    Troelsen, Anders; Mechlenburg, Inger; Gelineck, John;

    2009-01-01

    . PATIENTS AND METHODS: We examined 18 patients (18 hips, 2 men, median age 43 (32-56) years) with impingement test, FABER test, resisted straight leg raise test, ultrasound, and MR arthrography. They had had previous periacetabular osteotomies due to symptomatic, acetabular dysplasia. All hips showed no or...... only slight signs of osteoarthritis (Tönnis grade 0-1). RESULTS: MR arthrography identified labral tears in 17 of the 18 hips. Ultrasound had a sensitivity of 94%, a positive predictive value of 94%, and was false negative in only 1 case compared to MR arthrography. The impingement test had the best...

  18. DSA-guided percutaneous acetabuloplasty for the treatment of acetabular metastases: a clinical study

    International Nuclear Information System (INIS)

    Objective: To discuss the technical points, safety and clinical effectiveness of DSA-guided percutaneous acetabuloplasty (PA) for the treatment of acetabular metastases. Methods: Fifteen patients, including 6 males and 9 females, with acetabular malignant metastases were enrolled in this study. A total of 19 lesions were detected. The lesions were 13-25 mm in size (mean 19 ± 4 mm), the dose of PMMA used for per lesion was 5-13 ml (mean 8.2 ± 2.3 ml). All patients complained of greater or less degree of pain in their hips, 8 patients had to use walking stick, 4 patients showed limping although they could walk independently and three patients could not walk alone. DSA-guided percutaneous acetabuloplasty was performed in all patients and follow-up after the procedure was conducted for 1-12 months. Visual analogue score (VAS), walking state score and analgesic dosage taken by the patients were used for the evaluation of the clinical effectiveness. The complications were analyzed. All the data obtained were statistically analyzed with paired samples t test and analysis of variance by using SPSS12.0 statistical software. Results: The procedure was technically successful in all patients. Pain rating evaluated by the VAS decreased from a mean of 7.8 before surgery to a mean of 4.2 in 24 hours after surgery (P<0.01), which further decreased to 2.5 in one month (P<0.01), while walking state score increased from a mean of 1.5 before surgery to a mean of 2.5 in 24 hours after surgery (P<0.01). The analgesic dosage taken by the patient was reduced in 14 patients and remained the same in one patient. The bone cement leakage into para-acetabular soft tissues occurred in three cases and peripheral vascular exudation of acetabulum was observed in three cases with no obvious clinical symptoms. Conclusion: As a safe, reliable and minimally-invasive technique, DSA-guided percutaneous acetabuloplasty has excellent anti-pain effect in treating acetabular metastases. This therapy can

  19. Experimental and analytical validation of a modular acetabular prosthesis in total hip arthroplasty

    Directory of Open Access Journals (Sweden)

    Aram Luke

    2007-05-01

    Full Text Available Abstract A finite element model has been developed to predict in vivo micro motion between a modular acetabular cup and liner after cement less total hip arthroplasty. The purpose of this study is to experimentally validate the model. Six LVDT sensors were used to monitor the micromotion of the liner when subjected to loading conditions ranging from 250 N to 5000 N. Deformations at points of interest for both the experiment and FEM were compared. Results of the FEM with different coefficient of friction between the liner and the cup were investigated to correlate with the experimental results.

  20. Study of bone remodeling of two models of femoral cementless stems by means of DEXA and finite elements

    Directory of Open Access Journals (Sweden)

    López-Prats Fernando

    2010-05-01

    Full Text Available Abstract Background A hip replacement with a cemented or cementless femoral stem produces an effect on the bone called adaptive remodelling, attributable to mechanical and biological factors. All of the cementless prostheses designs try to achieve an optimal load transfer in order to avoid stress-shielding, which produces an osteopenia. Long-term densitometric studies taken after implanting ABG-I and ABG-II stems confirm that the changes made to the design and alloy of the ABG-II stem help produce less proximal atrophy of the femur. The simulation with FE allowed us to study the biomechanical behaviour of two stems. The aim of this study was, if possible, to correlate the biological and mechanical findings. Methods Both models with prostheses ABG-I and II have been simulated in five different moments of time which coincide with the DEXA measurements: postoperative, 6 months, 1, 3 and 5 years, in addition to the healthy femur as the initial reference. For the complete comparative analysis of both stems, all of the possible combinations of bone mass (group I and group II of pacients in two controlled studies for ABG-I and II stems, respectively, prosthetic geometry (ABG-I and ABG-II and stem material (Wrought Titanium or TMZF were simulated. Results and Discussion In both groups of bone mass an increase of stress in the area of the cancellous bone is produced, which coincides with the end of the HA coating, as a consequence of the bottleneck effect which is produced in the transmission of loads, and corresponds to Gruen zones 2 and 6, where no osteopenia can be seen in contrast to zones 1 and 7. Conclusions In this study it is shown that the ABG-II stem is more effective than the ABG-I given that it generates higher tensional values on the bone, due to which proximal bone atrophy diminishes. This biomechanical behaviour with an improved transmission of loads confirmed by means of FE simulation corresponds to the biological findings obtained with

  1. Trade-off between stress shielding and initial stability on an anatomical cementless stem shortening: in-vitro biomechanical study.

    Science.gov (United States)

    Yamako, Go; Chosa, Etsuo; Totoribe, Koji; Watanabe, Shinji; Sakamoto, Takero

    2015-08-01

    Shortened cementless femoral stems have become popular with the advent of minimally invasive total hip arthroplasty (THA). Successful THA requires initial stem stability and prevention of stress shielding-mediated bone loss, although the effect of stem shortening is controversial. Here we experimentally examined whether stem shortening affects stress shielding and initial stability. Anatomical stems (length, 120 mm) were cut to an 80 mm or 50 mm length. Ten tri-axial strain gauges measured the cortical strain on each stem-implanted femur to evaluate stress shielding. Two transducers measured axial relative displacement and rotation under single-leg stance loading. The 50 mm stem increased the equivalent strains with respect to the original stem in the proximal calcar region (31.0% relative to intact strain), proximal medial region (63.1%), and proximal lateral region (53.9%). In contrast, axial displacement and rotation increased with a decreasing stem length. However, the axial displacement of the 50 mm stem was below a critical value of 150 µm for bone ingrowth. Our findings indicate that, with regard to a reduction in stem length, there is a tradeoff between stress shielding and initial stability. Shortening the stem up to 50 mm can promote proximal load transfer, but bone loss would be inevitable, even with sufficient initial stability for long-term fixation. PMID:26117334

  2. The effects of pulsed low frequency magnetic field in early rehabilitation of patients with cementless total hip arthroplasty

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    Đurović Aleksandar

    2006-01-01

    Full Text Available Introduction: Early rehabilitation of patients with cementless total hip arthroplasty (cTHA includes different physical modalities and pulsed low frequency magnetic field (PLFMF, which effects have not been explored yet. Objective: To investigate the effects of PLFMF which was applied in different doses in early rehabilitation of patients with cTHA. Method: Prospective, controlled, clinical study included 90 patients, divided in three groups with 30 patients each. First two groups were treated with high (group A or low (group B doses of PLFMF, in addition to kinesitherapy. Control group C was treated only with kinesitherapy. Study was completed in three weeks. Results: Subjects of group A had significantly lower pain than group B (p<0.01 and group C (p<0.001 subjects in the first postoperative week. Pain in group B subjects was significantly lower than in group C in all three postoperative weeks (p<0.01. In relation to other two groups, subjects of group A had higher hip Harris score values at the end of the third postoperative week (p<0.05, and they were faster on 10-meter distance at the end of the first postoperative week (p<0.01. Conclusion: PLFMF used in low and high doses for patients with cTHA had significant effects on pain abatement, especially at higher doses. Improvement of function was earlier and more manifested in the group treated with high doses of PLFMF.

  3. Evaluation of Medial Acetabular Wall Bone Stock in Patients with Developmental Dysplasia of the Hip Using a Helical Computed Tomography Multiplanar Reconstruction Technique

    Energy Technology Data Exchange (ETDEWEB)

    Rui Yu Liu; Kun Zheng Wang; Chun Sheng Wang; Xiao Qian Dang; Zhi Qin Tong (Second Hospital Affiliated to the Medical College of Xi' an Jiaotong Univ., Xi' an Shaanxi (China))

    2009-08-15

    Background: The technique of medialization has been used to reconstruct acetabula at the level of true acetabula in total hip arthroplasty (THA) in patients with developmental dysplasia of the hip (DDH). Appreciation of the bone stock in the medial acetabular wall is significant for making an optimal acetabular reconstruction plan and avoiding complications. Purpose: To evaluate the bone stock of the medial acetabular wall and its relation to the degree of subluxation in patients with DDH using computed tomography (CT). Material and Methods: Helical CT scans of 27 hips were obtained from 21 patients with osteoarthritis secondary to DDH who were scheduled for total hip arthroplasty. Eleven hips belonged to Crowe class I, while 16 hips belonged to Crowe class II/III. The raw CT data were reprocessed in various planes by scrolling multiplanar reformation (MPR). Acetabular opening, depth, and medial bone stock, as indicated by the minimum thickness of the medial acetabular wall, were measured in the transverse reformed MPR plane. Results: The minimum thicknesses of the medial acetabular wall in Crowe-I and Crowe-II/III hips were 3.8+-2.1 mm and 7.1+-3.1 mm, respectively, with statistically significant differences between the groups (P<0.05). Furthermore, the bone stock in the medial acetabular wall correlated with the degree of subluxation (R=0.69) and the acetabular depth (R= ;- ;0.71). Conclusion: There was significantly more bone stock in the medial acetabular wall in patients with higher-degree subluxation than there was in the less-severe class. This difference should be taken into consideration when reconstructing acetabula in THA in patients with DDH using the technique of medialization

  4. Acetabular labral tears: contrast-enhanced MR imaging under continuous leg traction

    Energy Technology Data Exchange (ETDEWEB)

    Nishii, T. [Div. of Functional Diagnostic Imaging, Biomedical Research Center, Osaka Univ. Medical School, Suita (Japan); Nakanishi, K. [Dept. of Radiology, Osaka Univ. Medical School, Suita (Japan); Sugano, N. [Dept. of Orthopaedic Surgery, Osaka Univ. Medical School, Suita (Japan); Naito, H. [Div. of Functional Diagnostic Imaging, Biomedical Research Center, Osaka Univ. Medical School, Suita (Japan); Tamura, S. [Div. of Functional Diagnostic Imaging, Biomedical Research Center, Osaka Univ. Medical School, Suita (Japan); Ochi, T. [Dept. of Orthopaedic Surgery, Osaka Univ. Medical School, Suita (Japan)

    1996-05-01

    The objective of this study was to evaluate the effects of continuous leg traction on contrast-enhanced MR imaging of the hip joint and to determine whether MR imaging under these conditions is useful for demonstrating acetabular labral tears. Nineteen hips underwent MR imaging with a T1-weighted spin-echo sequence, followed by MR imaging under continuous leg traction after intravenous injection of gadolinium-DTPA. Joint fluid enhancement and labral contour detection were evaluated. Eleven hips had labral tears shown by conventional arthrography, arthroscopy and macroscopic surgical findings. Assessment of labral tears by MR imaging was correlated with the diagnosis based on these standard techniques. Joint fluid enhancement was obtained in all hips at 30 min after injection. Superior and inferior labral surfaces were completely delineated in 1 hip on the unenhanced MR images, and in 7 and 13 hips, respectively, on the enhanced images under traction. The enhanced images under traction depicted 9 of the 11 labral tears. Comparison between the unenhanced image and the enhanced image under traction avoided mistaking undercutting of the labrum for a tear in 4 hips. Contrast-enhanced MR imaging under traction was valuable for detecting labral tears non-invasively and without radiation. Follow-up examinations using this method in patients with acetabular dysplasia can help to clarify the natural course of labral disorders and enable better treatment planning. (orig./MG)

  5. Reliability of ultrasonographic measurements in suspected patients of developmental dysplasia of the hip and correlation with the acetabular index

    Directory of Open Access Journals (Sweden)

    Cem Copuroglu

    2011-01-01

    Full Text Available Background: Ultrasonography is accepted as a useful imaging modality in the early detection of developmental dysplasia of the hip (DDH. Early detection and early treatment of DDH prevents hip dislocation and related physical, social, economic, and psychological problems. The purpose of this study was to evaluate the reliability of ultrasonographic and roentgenographic measurements measured by seven different observers. Materials and Methods: The alpha angles of 66 hips in 33 patients were measured using the Graf method by seven different observers. Acetabular index degrees on plane roentgenograms were measured in order to assess the correlation between the ultrasonographic alpha angle and the radiographic acetabular index, which both show the bony acetabular depth, retrospectively. Results: The interclass correlation coefficient, measuring the interobserver reliability, was high and statistically significant for the ultrasonographic measurements. There was a negative correlation between the alpha angle and the acetabular index. Conclusions: Ultrasonography, when applied properly, is a reliable technique between different observers, in the diagnosis and follow up of DDH. When assessed concomitantly with the roentgenographic measurements, the results are reliable and statistically meaningful.

  6. Two-stage revision surgery with preformed spacers and cementless implants for septic hip arthritis: a prospective, non-randomized cohort study

    Directory of Open Access Journals (Sweden)

    Logoluso Nicola

    2011-05-01

    Full Text Available Abstract Background Outcome data on two-stage revision surgery for deep infection after septic hip arthritis are limited and inconsistent. This study presents the medium-term results of a new, standardized two-stage arthroplasty with preformed hip spacers and cementless implants in a consecutive series of adult patients with septic arthritis of the hip treated according to a same protocol. Methods Nineteen patients (20 hips were enrolled in this prospective, non-randomized cohort study between 2000 and 2008. The first stage comprised femoral head resection, debridement, and insertion of a preformed, commercially available, antibiotic-loaded cement hip spacer. After eradication of infection, a cementless total hip arthroplasty was implanted in the second stage. Patients were assessed for infection recurrence, pain (visual analog scale [VAS] and hip joint function (Harris Hip score. Results The mean time between first diagnosis of infection and revision surgery was 5.8 ± 9.0 months; the average duration of follow up was 56.6 (range, 24 - 104 months; all 20 hips were successfully converted to prosthesis an average 22 ± 5.1 weeks after spacer implantation. Reinfection after total hip joint replacement occurred in 1 patient. The mean VAS pain score improved from 48 (range, 35 - 84 pre-operatively to 18 (range, 0 - 38 prior to spacer removal and to 8 (range, 0 - 15 at the last follow-up assessment after prosthesis implantation. The average Harris Hip score improved from 27.5 before surgery to 61.8 between the two stages to 92.3 at the final follow-up assessment. Conclusions Satisfactory outcomes can be obtained with two-stage revision hip arthroplasty using preformed spacers and cementless implants for prosthetic hip joint infections of various etiologies.

  7. The cementless AGC 2000 knee prosthesis: 20-year results in a consecutive series

    DEFF Research Database (Denmark)

    Eriksen, Jamila; Christensen, Jan; Solgaard, Søren;

    2009-01-01

    survivorship analyses. All patients could be accounted for. With prosthesis revision as a failure criterion, the cumulative survival rate of all prosthetic components at 20 years was 84.4%. The fall in success rate was primarily due to early tibial and late patellar component failure. The cumulative survival...

  8. Acetabular deepening in the treatment of severe canine hip dysplasia Aprofundamento do acetábulo no tratamento de displasia coxofemoral grave em cães

    OpenAIRE

    Paulo Iamaguti; Luciana S. Iamaguti; Raquel Sartor

    2009-01-01

    A technique to restore acetabular anatomy by deepening the acetabular cavity and reconstructing the femoral head ligament and the joint capsule was tested on nine large breed dogs with severe hip dysplasia and acute subdislocation or dislocation. The technique consisted of two phases. First, all dogs were submitted to bilateral pectinotomy. In a second surgical intervention on the same dogs the acetabulum was approached and deepened, and the femoral head ligament and the joint capsule were re...

  9. Periprosthetic wear particle migration and distribution modelling and the implication for osteolysis in cementless total hip replacement.

    Science.gov (United States)

    Alidousti, Hamidreza; Taylor, Mark; Bressloff, Neil W

    2014-04-01

    In total hip replacement (THR), wear particles play a significant role in osteolysis and have been observed in locations as remote as the tip of femoral stem. However, there is no clear understanding of the factors and mechanisms causing, or contributing to particle migration to the periprosthetic tissue. Interfacial gaps provide a route for particle laden joint fluid to transport wear particles to the periprosthetic tissue and cause osteolysis. It is likely that capsular pressure, gap dimensions and micromotion of the gap during cyclic loading of an implant, play defining roles to facilitate particle migration. In order to obtain a better understanding of the above mechanisms and factors, transient two-dimensional computational fluid dynamic simulations have been performed for the flow in the lateral side of a cementless stem-femur system including the joint capsule, a gap in communication with the capsule and the surrounding bone. A discrete phase model to describe particle motion has been employed. Key findings from these simulations include: (1) Particles were shown to enter the periprosthetic tissue along the entire length of the gap but with higher concentrations at both proximal and distal ends of the gap and a maximum rate of particle accumulation in the distal regions. (2) High capsular pressure, rather than gap micromotion, has been shown to be the main driving force for particle migration to periprosthetic tissue. (3) Implant micromotion was shown to pump out rather than draw in particles to the interfacial gaps. (4) Particle concentrations are consistent with known distributions of (i) focal osteolysis at the distal end of the gap and (ii) linear osteolysis along the entire gap length. PMID:24495400

  10. A Feasibility Study into the Use of Three-Dimensional Printer Modelling in Acetabular Fracture Surgery

    Directory of Open Access Journals (Sweden)

    A. W. Yu

    2015-01-01

    Full Text Available There are a number of challenges associated with the operative treatment of acetabular fractures. The approach used is often extensive, while operative time and perioperative blood loss can also be significant. With the proliferation of 3D printer technology, we present a fast and economical way to aid the operative planning of complex fractures. We used augmented stereoscopic 3D CT reconstructions to allow for an appreciation of the normal 3D anatomy of the pelvis on the fractured side and to use the models for subsequent intraoperative contouring of pelvic reconstruction plates. This leads to a reduction in the associated soft tissue trauma, reduced intraoperative time and blood loss, minimal handling of the plate, and reduced fluoroscopic screening times. We feel that the use of this technology to customize implants, plates, and the operative procedure to a patient’s unique anatomy can only lead to improved outcomes.

  11. Precooling an acetabular liner makes its insertion into a metal shell easier.

    Science.gov (United States)

    Kyle, Richard F; Bourgeault, Craig A; Lew, William D; Bechtold, Joan E

    2006-02-01

    Temporary shrinkage of an acetabular polyethylene liner due to precooling could reduce the force required to snap the liner into its metal shell. This study documented cooling and heating rates of liners with a particular locking mechanism design, determined forces required to seat liners in their shells as a function of temperature, and quantified the force surgeons can exert with their thumbs when seating a liner. It took up to 8 minutes to cool 58- and 70-mm liners in an ice-water bath from room temperature to near 0 degrees C, and up to 24 minutes to subsequently warm these liners to near body temperature. Forces required to seat liners were greater at room and body temperatures than at 0 degrees C. Liners precooled to 0 degrees C required insertion forces that could be generated manually by surgeons. PMID:16520215

  12. Simultaneous bilateral shoulder and bilateral central acetabular fracture dislocation: What to do?

    Institute of Scientific and Technical Information of China (English)

    Hardik Sheth; Abhijeet Ashok Salunke; Ramesh Panchal; Jimmy Chokshi; G.I.Nambi; Saranjeet Singh; Amit Patel

    2016-01-01

    Musculoskeletal injuries following seizures have a high morbidity and mortality.These injuries are often missed and the diagnosis is delayed due to a lack of clinical suspicion and appropriate investigations.We report a case of 72 years old male with simultaneous bilateral central acetabular fracture dislocation and bilateral posterior shoulder fracture dislocation secondary to an epileptic seizure.Present study highlights the significance of clinical suspicion and clinico-radiological evaluation for diagnosis of a rare injury following episode of seizures.Simultaneous fracture dislocation of all four limbs treated with a holistic approach can lead to a good functional recovery.Surgical management with open reduction and internal fixation is preferred and replacement arthroplasty should be reserved for cases with implant failure and elderly patients.

  13. Outcome of periacetabular osteotomy for the management of acetabular dysplasia: experience in an academic centre.

    LENUS (Irish Health Repository)

    Burke, Neil G

    2011-02-01

    Periacetabular osteotomy (PAO) is a very effective reconstructive procedure for treatment of acetabular dysplasia. An orthopaedic paediatric surgeon and a reconstructive hip arthroplasty surgeon performed this procedure together in the early phase of their learning curve and then performed it individually. The early clinical and radiographic results of 85 consecutive PAOs performed in this academic orthopaedic unit were reviewed. The mean Merle-d\\'Aubigné score increased from 12.4 preoperatively to 16 at follow-up. Pre-operatively 73 hips were anteverted and 12 were neutral or retroverted. The mean angle of Wiberg improved from 5 degrees to 21 degrees (p < 0.0001) in anteverted hips, and from 9 degrees to 30 degrees in neutral or retroverted hips. The mean angle of Lequesne and de Sèze improved from 6 degrees to 35 degrees (p < 0.0001) in anteverted hips, and in neutral or retroverted hips from 9 degrees to 30 degrees (p < 0.0001). The acetabular index improved from 26 degrees to 8 degrees (p < 0.0001) in anteverted hips, and from 21 degrees to 7 degrees (p < 0.0001) in neutral or retroverted hips. Over the 7 year period the blood loss and operative time improved from 2000 ml to 900 ml and 4 hours to 2 hours respectively. Four hips (four patients) required conversion to total hip replacement. The radiographic correction and improved clinical scores are similar to those in previous studies. This study shows a survival rate of 94% at 58 months following periacetabular osteotomy. The learning curve and the early results of this procedure performed in our academic unit are encouraging.

  14. Outcome of operative treatment of acetabular fractures: short term follow-up

    International Nuclear Information System (INIS)

    Fractures of the acetabulum result from high energy accidents. The anatomic location of the acetabulum, as well as the three-dimensional structure of the bone, makes the treatment of these injuries extremely challenging. The objective of this study was to determine the outcome of operative treatment of acetabulum fractures with one year follow-up. Methods: In this descriptive case series, 31 patients with acetabular fracture were admitted in North West General Hospital, Peshawar, from July 2010 to Sept 2013. Patients were followed-up till one year. In follow-up, patients were assessed clinically with Merle Aubigne and Postel grading method. Radiological assessment was done using Matta criteria. Results: All patients were male. Twelve (38.7 %) were managed non-operatively, as they fulfilled criteria for non-operative treatment and 19 (61.3%) patients were operated after fulfilling the criteria for internal fixation; they were included for analysis. Ages ranged from 20-60 years with mean age of 37.21 ± 10.07 years. Fourteen (73.7%) patients had anatomic reduction and 5 (26.3 %) patients had imperfect reduction based on Matta radiographic criteria. At 1 year follow-up, we had 16 (84.2 %) excellent hips, 2 (10.5%) good hips and 1 (5.3%) poor hip , based on radiographs; and clinically we had 9 (47.4 %) hips with excellent function, 7 (36.8 %) hips with good outcome, 2 (10.5 %) had fair function and 1 (5.3 %) patient had poor function. Conclusion: Our results show that internal fixation of acetabular fractures lead to good outcome in majority of patients. (author)

  15. Supra-Acetabular Brown Tumor due to Primary Hyperparathyroidism Associated with Chronic Renal Failure

    Directory of Open Access Journals (Sweden)

    Rosaria M. Ruggeri

    2010-01-01

    Full Text Available A 63-year-old woman presented to the Orthopedic Unit of our hospital complaining of right hip pain of 6 months'duration associated with a worsening limp. Her past medical history included chronic renal insufficiency. Physical examination revealed deep pain in the iliac region and severe restriction of the right hip's articular function in the maximum degrees of range of motion. X-rays and CT scan detected an osteolytic and expansive lesion of the right supra-acetabular region with structural reabsorption of the right iliac wing. 99mTc-MDP whole-body bone scan showed an abnormal uptake in the right iliac region. Bone biopsy revealed an osteolytic lesion with multinucleated giant cells, indicating a brown tumor. Serum intact PTH was elevated (1020 pg/ml; normal values, 12 62 pg/ml, but her serum calcium was normal (total = 9.4 mg/dl, nv 8.5–10.5; ionized = 5.0 mg/dl, nv 4.2–5.4 due to the coexistence of chronic renal failure. 99mTc-MIBI scintigraphy revealed a single focus of sestamibi accumulation in the left retrosternal location, which turned out to be an intrathoracic parathyroid adenoma at surgical exploration. After surgical removal of the parathyroid adenoma, PTH levels decreased to 212 pg/ml. Three months after parathyroidectomy, the imaging studies showed complete recovery of the osteolytic lesion, thus avoiding any orthopedic surgery. This case is noteworthy because (1 primary hyperparathyroidism was not suspected due to the normocalcemia, likely attributable to the coexistence of chronic renal failure; and (2 it was associated with a brown tumor of unusual location (right supra-acetabular region.

  16. Analysis of acetabular version in the native hip: comparison between 2D axial CT and 3D CT measurements

    Energy Technology Data Exchange (ETDEWEB)

    Dandachli, Wael [Department of Orthopaedic Surgery, Imperial College London Hospitals, London (United Kingdom); Ul Islam, Saif; Tippett, Richard; Hall-Craggs, Margaret A.; Witt, Johan D. [University College London Hospitals, London (United Kingdom)

    2011-07-15

    To compare two-dimensional (2D) axial with three-dimensional (3D) computerized tomography (CT) measurements of acetabular version in native hips. CT scans of 34 hips in 17 consecutive patients being investigated for femoroacetabular impingement were analyzed. Acetabular version was measured using 2D CT at two different axial levels, one cranial (slice 2) and the other at the equator (slice 3). The measurements were repeated after correction for pelvic tilt. The results were compared to the measurements of anatomical version obtained using a 3D CT method that automatically corrects for pelvic tilt. The mean acetabular version using the 3D CT method was 15.7 (SD 6.9 ). The mean version using slice 2 was 9.3 (SD 6.5 ) before correction for pelvic tilt and 15.7 (SD 8.0 ) after the correction. The mean version using slice 3 was 16.4 (SD 4.2 ) before tilt correction and 19.0 (SD 5.0 ) after the correction. In relation to the 3D method, the intraclass correlation coefficient (ICC) was 0.58 for the uncorrected and 0.93 for the corrected slice 2 method. For the uncorrected and corrected slice 3 methods, the ICC was 0.64 and 0.89, respectively. The 2D axial methods produced variable results. The results that correlated best with the 3D method were those of the cranial slice (slice 2) after correction for pelvic tilt. Interpretation of 2D axial CT measurements of acetabular version should be done with caution. The level at which the measurement is done and the presence of pelvic tilt appear to be significant factors. (orig.)

  17. Study of the three-dimensional orientation of the labrum: its relations with the osseous acetabular rim

    Science.gov (United States)

    Bonneau, Noémie; Bouhallier, July; Baylac, Michel; Tardieu, Christine; Gagey, Olivier

    2012-01-01

    Understanding the three-dimensional orientation of the coxo-femoral joint remains a challenge as an accurate three-dimensional orientation ensure an efficient bipedal gait and posture. The quantification of the orientation of the acetabulum can be performed using the three-dimensional axis perpendicular to the plane that passes along the edge of the acetabular rim. However, the acetabular rim is not regular as an important indentation in the anterior rim was observed. An innovative cadaver study of the labrum was developed to shed light on the proper quantification of the three-dimensional orientation of the acetabulum. Dissections on 17 non-embalmed corpses were performed. Our results suggest that the acetabular rim is better represented by an anterior plane and a posterior plane rather than a single plane along the entire rim as it is currently assumed. The development of the socket from the Y-shaped cartilage was suggested to explain the different orientations in these anterior and posterior planes. The labrum forms a plane that takes an orientation in between the anterior and posterior parts of the acetabular rim, filling up inequalities of the bony rim. The vectors VL, VA2 and VP, representing the three-dimensional orientation of the labrum, the anterior rim and the posterior rim, are situated in a unique plane that appears biomechanically dependent. The three-dimensional orientation of the acetabulum is a fundamental parameter to understand the hip joint mechanism. Important applications for hip surgery and rehabilitation, as well as for physical anthropology, were discussed. PMID:22360458

  18. A NUMERICAL STUDY OF THE CONTACT PRESSURE BETWEEN A FEMORAL HEAD AND ACETABULAR CUP OF A TOTAL HIP REPLACEMENT

    Czech Academy of Sciences Publication Activity Database

    Koukal, M.; Florian, Z.; Fuis, Vladimír

    Brno : Brno University of Technology, 2006 - (Burša, J.; Fuis, V.), s. 126-127 ISBN 80-214-3232-2. [Human Biomechanics 2006. Hrotovice (CZ), 13.11.2006-16.11.2006] R&D Projects: GA ČR(CZ) GA101/05/0136 Institutional research plan: CEZ:AV0Z20760514 Keywords : FEM * ceramic head * contact pressure * acetabular cup Subject RIV: BO - Biophysics

  19. Computer aided technology assesses adult acetabular dysplasia after total hip arthroplasty:biological performance%计算机辅助技术评价成人髋臼发育不良全髋关节置换生物性能分析

    Institute of Scientific and Technical Information of China (English)

    邵正海; 徐卫东

    2016-01-01

    Bone and Joint Surgery, Changhai Hospital, Second Military Medical University of Chinese PLA from January 2015 to August 2015 were selected and analyzed. Al the enrol ed patients underwent total hip arthroplasty. Al the patients were randomly divided into control and computer-aided technology groups. CT scanning was conducted in these two groups before replacement. Three-dimensional reconstruction measuring and surgical rehearsal on the acetabular site were conducted using M3D visualization software in the computer-aided technology group. The effects and biological properties of total hip arthroplasty were compared between these two groups. RESULTS AND CONCLUSION: Patients in these two groups primarily healed after replacement. The excel ent and good rate, Harris score after treatment, acetabular component, valgus angle and anteversion in the computer-aided technology group were significantly higher than those in the control group (P < 0.05). The acetabular cup abduction angle offset degrees, acetabular cup anteversion offset degrees, and the incidences of complications after replacement were significantly decreased compared with those in the control group (P < 0.05). These results suggest that the effect of computer-aided evaluation in adult acetabular dysplasia after total hip arthroplasty is ideal, and can accurately grasp the true acetabular anatomical characteristics and the corresponding relationship with the prosthesis, so as to help patients to choose the proper acetabulum and acetabular prosthesis and reconstruction ways and improve the biological performance of acetabulum after replacement, with a high clinical value.

  20. Acetabular retroversion as a rare cause of chronic hip pain: recognition of the ''figure-eight'' sign

    Energy Technology Data Exchange (ETDEWEB)

    Banks, Kevin P. [Brooke Army Medical Center, Department of Radiology, Fort Sam Houston, TX (United States); Grayson, David E. [Wilford Hall Medical Center, Department of Radiology, Lackland Air Force Base, TX (United States)

    2007-06-15

    While well-recognized in the orthopedic literature as a cause of chronic hip pain, acetabular retroversion has not been specifically described in the radiologic literature. Acetabular retroversion represents a particular form of hip dysplasia characterized by abnormal posterolateral orientation of the acetabulum. This pathophysiology predisposes the individual to subsequent anterior impingement of the femoral neck upon the anterior acetabular margin and fibrous labrum. Without treatment, cases may progress to damage of the anterior labrum and cartilage, with eventual early onset of osteoarthritic disease. This impinging condition has been described as occurring in isolation or as part of a complex dysplasia. We describe two cases of acetabular retroversion diagnosed by conventional radiographic evaluation of the pelvis, one in isolation and one occurring in the setting of a larger congenital syndrome. These cases illustrate the utility of the ''figure-eight'' sign in identifying abnormalities of acetabular version and thus assisting clinicians in properly identifying these individuals so that appropriate therapy may be instituted. (orig.)

  1. Cementless total hip arthroplasty with the rectangular titanium Zweymuller stem. A concise follow-up, at a minimum of fifteen years, of a previous report.

    Science.gov (United States)

    Grübl, Alexander; Chiari, Catharina; Giurea, Alexander; Gruber, Martin; Kaider, Alexandra; Marker, Martina; Zehetgruber, Harald; Gottsauner-Wolf, Florian

    2006-10-01

    Between October 1986 and November 1987, 208 total hip arthroplasties were performed with use of the cementless Zweymüller stem and a threaded cup in 200 consecutive patients. Of 102 patients (108 hips) who were available for follow-up at a minimum of 180 months postoperatively, eighty-three (eighty-nine hips) had the primary joint replacement still intact. No stem had been revised because of aseptic loosening, but we found various degrees of osteolysis around sixteen (18%) of the implants. The probability of survival of the stem at fifteen years was 0.98 (95% confidence interval, 0.96 to 1.00). The probability of survival of the cup was 0.85 (95% confidence interval, 0.79 to 0.91). PMID:17015598

  2. Retrieval analysis of a failed TriboFit polycarbonate urethane acetabular buffer.

    Science.gov (United States)

    Biant, Leela C; Gascoyne, Trevor C; Bohm, Eric R; Moran, Matthew

    2016-03-01

    The purpose of this research was to determine the failure mechanisms and damage features of a TriboFit acetabular buffer implanted directly against a native, prepared acetabulum which was revised after 11months. Retrieval analyses were carried out via light microscopy, gravimetric wear assessment, and observer scoring of visible damage features on the buffer. The volume of material abraded from the backside of the buffer was estimated via three-dimensional reconstruction using a laser scanner. Scanning electron microscopy was used to confirm damage features and mechanisms. Severe abrasion to the backside of the buffer was the primary damage feature, while stippling damage was seen on the articular surface of the buffer. Material loss due to backside abrasion was approximated to be between 0.13360.085 g (gravimetric analyses) and 0.19360.053 g (three-dimensional reconstruction). Implantation of the TriboFit buffer against the patient's native acetabulum without a metal backing allowed for significant movement of the buffer against the bone, resulting in the abrasion seen on this implant. The stippling damage on the articular surface indicates an adhesive wear mechanism which exacerbates movement of the buffer against the acetabulum, thereby increasing backside abrasion. PMID:26833696

  3. The effect of femoro-acetabular impingement on the kinematics and kinetics of the hip joint.

    Science.gov (United States)

    Alshameeri, Zeiad; Khanduja, Vikas

    2014-08-01

    Gait analysis is an objective tool that has been used to assess and monitor treatment for many musculoskeletal conditions. Recently, it has been used to assess the impact of femoro-acetabular impingement (FAI) on the hip and lower limb movements. There have been a fairly limited number of studies published so far reporting unexpected and inconsistent results, which calls for more research to be conducted in this arena. In the light of the limited data available, it has been challenging to reconcile the contradictions in some of these results, and therefore no coherent conclusions could be drawn. In this short article, we attempt to explain some of the abnormal kinematic and kinetic patterns associated with FAI by highlighting similarities between the gait seen in early osteoarthritis (OA) and that of FAI. We also propose an approach for future research in this field and emphasise the importance of quantifying early OA in FAI based on magnetic resonance imaging (MRI) scans and the amount of chondral damage seen during open or arthroscopic surgery. PMID:24687267

  4. Should money follow the patient: Financial implication for being the National Centre for the Treatment and Management of Pelvic and Acetabular Fractures in Ireland.

    LENUS (Irish Health Repository)

    Kelly, M E

    2013-03-13

    BACKGROUND: Pelvic and acetabular fractures are complex injuries requiring specialist treatment. Our institution is the National Centre for Treatment and Management of these injuries. AIM: To audit all referrals to our institution over a 6-month period and calculate the cost incurred by being the national referral centre. METHODS: Retrospective review of database, and subsequent allocation of Casemix points to assess total cost of treatment for each patient referred to our institution. RESULTS: 103 patients referred with pelvic or acetabular fracture for operative management. The furthest referral distance was 181miles. Over-all, the length of stay was 15.4 days. The average inclusive cost for a referral to our unit for operative management was €16,302. CONCLUSION: Pelvic and acetabular fractures are complex injuries that require specialist referral unit management. However for these units to remain sustainable money needs to "follow the patient".

  5. Achados em ressonância magnética artrográfica de indivíduos com lesão do labrum acetabular Magnetic resonance arthrographic findings in subjects with acetabular labral tears

    OpenAIRE

    André Luiz Almeida Pizzolatti; Alessandro Haupenthal; Adriano Marostika; Richard Prazeres Canella; Ademar José de Oliveira Paes Junior; Sérgio Marcondes Brincas

    2011-01-01

    OBJETIVO: Descrever os achados em artro RM de sujeitos com suspeita de lesão do labrum acetabular. MÉTODO: Foram analisadas 108 artro RM de quadris em 2007/2008. Dois radiologistas independentemente analisaram as imagens e foi considerada a resposta comum entre eles. Com base em seus pareceres observou-se o local e estadiamento das lesões labrais e condrais, as alterações anatômicas, e a presença de tendinite e bursite trocantérica. RESULTADO: As lesões labrais grau I ocorreram em 41% dos cas...

  6. The acetabular fossa hot spot on {sup 18}F-FDG PET/CT: epidemiology, natural history, and proposed etiology

    Energy Technology Data Exchange (ETDEWEB)

    Kubicki, Shelby L. [Trinity University, San Antonio, TX (United States); Richardson, Michael L. [University of Washington, Department of Radiology, Seattle, WA (United States); Martin, Thomas [X-Ray Associates of New Mexico, Department of Radiology, Albuquerque, NM (United States); Rohren, Eric [The University of Texas M.D. Anderson Cancer Center, Department of Diagnostic Radiology, Division of Nuclear Medicine, Houston, TX (United States); Wei, Wei [The University of Texas M.D. Anderson Cancer Center, Department of Biostatistics, Houston, TX (United States); Amini, Behrang [The University of Texas M.D. Anderson Cancer Center, Department of Diagnostic Radiology, Division of Musculoskeletal Radiology, Houston, TX (United States)

    2015-01-15

    To describe a benign focus of increased activity in the acetabular fossa (the acetabular fossa hot spot, AFHS) on {sup 18}F-FDG PET/CT that can mimic a neoplasm. {sup 18}F-FDG PET/CT images from four patient populations were examined. Group 1 (n = 13) was collected from a search of radiology reports and used to define the AFHS and for hypothesis generation. Group 2 (n = 1,150) was used for prevalence of AFHS. Group 3 (n = 1,213) had PET/CT and MRI pelvis within a week of each other and was used to correlate metabolic and anatomic findings. Group 4 (n = 100) was used to generate the control group. Data were collected on demographics, common comorbidities, underlying cancer diagnosis and status, and hip symptoms. Prevalence of AFHS was 0.36 % (95 % CI 0.10-0.91 %). None progressed to malignancy or was associated with cancer status. The majority (71 %) were on the left, and 6 % were bilateral. Mean SUV{sub max} of the AFHS was 4.8 (range, 2.7-7.8). Male patients were more likely to have the AFHS (OR = 8.69, 95 % CI 1.88-40.13). There was no difference with respect to other collected data, including hip symptoms. Average minimum duration of AFHS was 346 days (range, 50-1,010 days). Readers did not detect corresponding hip abnormalities on MRIs. AFHS is a benign finding that may be caused by subclinical ligamentum teres injury, focal synovitis, or degeneration of acetabular fossa fat. Despite uncertainty regarding its etiology, recognition of AFHS as a benign finding can prevent morbidity associated with unnecessary biopsy or initiation of therapy. (orig.)

  7. The acetabular fossa hot spot on 18F-FDG PET/CT: epidemiology, natural history, and proposed etiology

    International Nuclear Information System (INIS)

    To describe a benign focus of increased activity in the acetabular fossa (the acetabular fossa hot spot, AFHS) on 18F-FDG PET/CT that can mimic a neoplasm. 18F-FDG PET/CT images from four patient populations were examined. Group 1 (n = 13) was collected from a search of radiology reports and used to define the AFHS and for hypothesis generation. Group 2 (n = 1,150) was used for prevalence of AFHS. Group 3 (n = 1,213) had PET/CT and MRI pelvis within a week of each other and was used to correlate metabolic and anatomic findings. Group 4 (n = 100) was used to generate the control group. Data were collected on demographics, common comorbidities, underlying cancer diagnosis and status, and hip symptoms. Prevalence of AFHS was 0.36 % (95 % CI 0.10-0.91 %). None progressed to malignancy or was associated with cancer status. The majority (71 %) were on the left, and 6 % were bilateral. Mean SUVmax of the AFHS was 4.8 (range, 2.7-7.8). Male patients were more likely to have the AFHS (OR = 8.69, 95 % CI 1.88-40.13). There was no difference with respect to other collected data, including hip symptoms. Average minimum duration of AFHS was 346 days (range, 50-1,010 days). Readers did not detect corresponding hip abnormalities on MRIs. AFHS is a benign finding that may be caused by subclinical ligamentum teres injury, focal synovitis, or degeneration of acetabular fossa fat. Despite uncertainty regarding its etiology, recognition of AFHS as a benign finding can prevent morbidity associated with unnecessary biopsy or initiation of therapy. (orig.)

  8. Precision of radiostereometric analysis (RSA) of acetabular cup stability and polyethylene wear improved by adding tantalum beads to the liner

    DEFF Research Database (Denmark)

    Nebergall, Audrey K; Rader, Kevin; Palm, Henrik;

    2015-01-01

    Background and purpose - In traditional radiostereometric analysis (RSA), 1 segment defines both the acetabular shell and the polyethylene liner. However, inserting beads into the polyethylene liner permits employment of the shell and liner as 2 separate segments, enabling distinct analysis of the...... precision of 3 measurement methods in determining femoral head penetration and shell migration. Patients and methods - The UmRSA program was used to analyze the double examinations of 51 hips to determine if there was a difference in using the shell-only segment, the liner-only segment, or the shell + liner...

  9. The Use of Iliac Stem Prosthesis for Acetabular Defects following Resections for Periacetabular Tumors

    Science.gov (United States)

    De Paolis, Massimiliano; Romagnoli, Carlo; Alì, Nikolin; Giannini, Sandro; Donati, Davide Maria

    2013-01-01

    Introduction. The management of pelvic tumors is a challenge for orthopaedic oncologists due to the complex anatomy of the pelvis and the need to have extensive exposure. Various reconstructive techniques have been proposed with poor functional results and a high percentage of complications. Our purpose is to determine the functional results and the rate of complications of iliac stem prosthesis for acetabular defects following resections for periacetabular tumors. Materials and Methods. Between 1999 and 2012, 45 patients underwent pelvic resections for periacetabular bone tumors followed by reconstruction with stem cup prosthesis. The most common diagnosis was CS (chondrosarcoma, 29 cases), followed by OS (osteosarcoma, 9 cases) and metastasis (3 cases). In 33 cases, this implant was associated with massive bone allografts. Minimum follow-up required to evaluate functional outcome was 2 years. We classified pelvic resections according to Enneking and Dunham's classification and we used MSTS (musculoskeletal tumor system) score to evaluate functional outcomes. Results and Discussion. Sixteen patients died of their disease, three were lost to follow-up, four are alive with disease, and twenty-two are alive with no evidence of disease. Fifteen patients had local recurrence. Sixteen patients had bone or lung metastasis. We have had 6 infections, 2 aseptic loosening, and 2 cases of hip dislocation. Iliac sovracetabular osteotomy was fused in all cases at 10 months from surgery. Functional results were good or excellent in 25 of 31 patients with long-term follow-up (77%), with a percentage similar to that reported in the literature. Conclusion. The use of iliac stem prosthesis is a simple reconstructive technique that reduces operative times and risk of infection. It allows having good results and low rate of complications, but it should be performed in selected cases and centres of reference. PMID:24250275

  10. Three-dimensional magnetic resonance imaging analysis of hip morphology in the assessment of femoral acetabular impingement

    Energy Technology Data Exchange (ETDEWEB)

    Kavanagh, E.C. [Department of Radiology, Mater Misericordiae Hospital, Dublin (Ireland); Read, P.; Carty, F.; Zoga, A.C. [Department of Radiology, Thomas Jefferson University Hospital, Philadelphia, PA (United States); Parvizi, J. [The Rothman Institute of Orthopedics, Philadelphia, PA (United States); Morrison, W.B., E-mail: William.Morrison@Jefferson.edu [Department of Radiology, Thomas Jefferson University Hospital, Philadelphia, PA (United States)

    2011-08-15

    Aim: To determine a possible association between femoral-acetabular impingement (FAI) volume and the development of labral tear using a three-dimensional (3D) model reconstruction of the acetabulum and the femoral head. Materials and methods: Magnetic resonance arthrography images of the hip in 42 patients with pain and suspected labral tear were acquired using a 1.5 T MRI machine. Using 3D analysis software, outlines of the acetabular cup and femoral head were drawn and 3D reconstruction obtained. To control for differences in patient size, ratios of acetabulum : femoral head volume (AFV) and acetabulum : femoral head surface area (AFA) were used for analysis. The association between volume of acetabulum : femoral head and FAI was investigated using ANOVA analysis. Results: There were 19 men and 23 women with a mean age of 39 years (range 18-78 years). The average AFV was 0.64 (range 0.37-1.05, SD 0.16) and AFA was 0.73 (range 0.36-1.26, SD 0.23). Herniation pit was significantly associated with a small AFV. Conclusion: Femoral neck herniation pits are associated with a low AFV. Gross volume and surface area ratios do not appear to correlate with labral tears or cartilage loss. This technique will enable more advanced analysis of morphological variations associated with FAI.

  11. Supra-acetabular fixation and sacroiliac screws for treating unstable pelvic ring injuries: preliminary results from 20 patients☆

    Science.gov (United States)

    Guimarães, Rodrigo Pereira; de Góes Ribeiro, Arthur; Ulson, Oliver; de Ávila, Ricardo Bertozzi; Ono, Nelson Keiske; Polesello, Giancarlo Cavalli

    2016-01-01

    Objective To analyze the treatment results from 20 patients who underwent an alternative osteosynthesis method as definitive treatment for pelvic ring fractures. Methods A retrospective analysis was conducted on a series of 20 patients with pelvic ring fractures (Tile type C) and a high risk of postoperative infection, who were treated at Santa Casa de Misericórdia de São Paulo between August 2004 and December 2012. The patients underwent percutaneous supra-acetabular external fixation in association with cannulated 7.0 mm iliosacral screws. Results The patients’ mean age was 40 years (range 22–77 years) and the mean length of follow-up was 18.5 months (range 3–69 months). At the end of the treatment, ten patients (50%) were classified as having good results, nine patients (45%) had fair results and one patient (5%) did not have any improvement. Six patients presented complications, and paresthesia of the lateral femoral cutaneous nerve was the most frequent of these (two patients). Conclusion Supra-acetabular external fixation in association with iliosacral percutaneous osteosynthesis is a good definitive treatment method for patients with a high risk of postoperative infection. PMID:27069879

  12. Computer assisted determination of acetabular cup orientation using 2D-3D image registration

    International Nuclear Information System (INIS)

    2D-3D image-based registration methods have been developed to measure acetabular cup orientation after total hip arthroplasty (THA). These methods require registration of both the prosthesis and the CT images to 2D radiographs and compute implant position with respect to a reference. The application of these methods is limited in clinical practice due to two limitations: (1) the requirement of a computer-aided design (CAD) model of the prosthesis, which may be unavailable due to the proprietary concerns of the manufacturer, and (2) the requirement of either multiple radiographs or radiograph-specific calibration, usually unavailable for retrospective studies. In this paper, we propose a new method to address these limitations. A new formulation for determination of post-operative cup orientation, which couples a radiographic measurement with 2D-3D image matching, was developed. In our formulation, the radiographic measurement can be obtained with known methods so that the challenge lies in the 2D-3D image matching. To solve this problem, a hybrid 2D-3D registration scheme combining a landmark-to-ray 2D-3D alignment with a robust intensity-based 2D-3D registration was used. The hybrid 2D-3D registration scheme allows computing both the post-operative cup orientation with respect to an anatomical reference and the pelvic tilt and rotation with respect to the X-ray imaging table/plate. The method was validated using 2D adult cadaver hips. Using the hybrid 2D-3D registration scheme, our method showed a mean accuracy of 1.0 ± 0.7 (range from 0.1 to 2.0 ) for inclination and 1.7 ± 1.2 (range from 0.0 to 3.9 ) for anteversion, taking the measurements from post-operative CT images as ground truths. Our new solution formulation and the hybrid 2D-3D registration scheme facilitate estimation of post-operative cup orientation and measurement of pelvic tilt and rotation. (orig.)

  13. Computer assisted determination of acetabular cup orientation using 2D-3D image registration

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Guoyan; Zhang, Xuan [University of Bern, Institute for Surgical Technology and Biomechanics, Bern (Switzerland)

    2010-09-15

    2D-3D image-based registration methods have been developed to measure acetabular cup orientation after total hip arthroplasty (THA). These methods require registration of both the prosthesis and the CT images to 2D radiographs and compute implant position with respect to a reference. The application of these methods is limited in clinical practice due to two limitations: (1) the requirement of a computer-aided design (CAD) model of the prosthesis, which may be unavailable due to the proprietary concerns of the manufacturer, and (2) the requirement of either multiple radiographs or radiograph-specific calibration, usually unavailable for retrospective studies. In this paper, we propose a new method to address these limitations. A new formulation for determination of post-operative cup orientation, which couples a radiographic measurement with 2D-3D image matching, was developed. In our formulation, the radiographic measurement can be obtained with known methods so that the challenge lies in the 2D-3D image matching. To solve this problem, a hybrid 2D-3D registration scheme combining a landmark-to-ray 2D-3D alignment with a robust intensity-based 2D-3D registration was used. The hybrid 2D-3D registration scheme allows computing both the post-operative cup orientation with respect to an anatomical reference and the pelvic tilt and rotation with respect to the X-ray imaging table/plate. The method was validated using 2D adult cadaver hips. Using the hybrid 2D-3D registration scheme, our method showed a mean accuracy of 1.0 {+-} 0.7 (range from 0.1 to 2.0 ) for inclination and 1.7 {+-} 1.2 (range from 0.0 to 3.9 ) for anteversion, taking the measurements from post-operative CT images as ground truths. Our new solution formulation and the hybrid 2D-3D registration scheme facilitate estimation of post-operative cup orientation and measurement of pelvic tilt and rotation. (orig.)

  14. Periacetabular osteotomy for acetabular dysplasia%髋臼周围截骨术治疗髋臼发育不良

    Institute of Scientific and Technical Information of China (English)

    李华; 王云清; 魏东

    2011-01-01

    目的 探讨髋臼周围截骨术治疗髋臼发育不良的方法 及疗效.方法 对36例髋臼发育不良患者(43髋)行手术治疗,通过髋臼周围截骨、旋转髋臼向前外侧移位恢复髋臼的正确位置,并增加髋臼覆盖面.结果 36例均获随访,时间 6个月~3年.术后髋痛、跛行完全消失或有明显改善,髋关节活动范围基本正常.CE角和Sharp角均基本恢复正常.结论 髋臼周围截骨术可有效改善临床症状,恢复髋关节的生物力学特点,是治疗髋臼发育不良的有效方法.%Objective To discuss the method and effect of the treatment of acetabular dysplasia by periacetabular acetabular osteotomy. Methods Periacetabular osteotomy was performed to correct 36 patients( 43 hips )with dysplastic acetabulum through rotating the acetabulum anterolaterally, by which the position and acetabular coverage of the femoral head was restored to nearly normal. Results 36 patients with acetabular dysplasia were all followed up for six months to three years. After operation, in the majority, the hip limp or pain with exertion disappeared, and a satisfactory range of motion had been restored. CE angle and Sharp angle were restored to nearly normal value. Conclusions Periacetabular osteotomy is effectively to improve the clinical symptoms, and restore the hip biomechanics characteristics,which is ideal for the treatment of developmental acetabular dysplasia.

  15. The effect of geometry and abduction angle on the stresses in cemented UHMWPE acetabular cups – finite element simulations and experimental tests

    Directory of Open Access Journals (Sweden)

    Santavirta Seppo S

    2005-05-01

    Full Text Available Abstract Background Contact pressure of UHMWPE acetabular cup has been shown to correlate with wear in total hip replacement (THR. The aim of the present study was to test the hypotheses that the cup geometry, abduction angle, thickness and clearance can modify the stresses in cemented polyethylene cups. Methods Acetabular cups with different geometries (Link®: IP and Lubinus eccentric were tested cyclically in a simulator at 45° and 60° abduction angles. Finite element (FE meshes were generated and two additional designs were reconstructed to test the effects of the cup clearance and thickness. Contact pressures at cup-head and cup-cement interfaces were calculated as a function of loading force at 45°, 60° and 80° abduction angles. Results At the cup-head interface, IP experienced lower contact pressures than the Lubinus eccentric at low loading forces. However, at higher loading forces, much higher contact pressures were produced on the surface of IP cup. An increase in the abduction angle increased contact pressure in the IP model, but this did not occur to any major extent with the Lubinus eccentric model. At the cup-cement interface, IP experienced lower contact pressures. Increased clearance between cup and head increased contact pressure both at cup-head and cup-cement interfaces, whereas a decreased thickness of polyethylene layer increased contact pressure only at the cup-cement interface. FE results were consistent with experimental tests and acetabular cup deformations. Conclusion FE analyses showed that geometrical design, thickness and abduction angle of the acetabular cup, as well as the clearance between the cup and head do change significantly the mechanical stresses experienced by a cemented UHMWPE acetabular cup. These factors should be taken into account in future development of THR prostheses. FE technique is a useful tool with which to address these issues.

  16. A porous tantalum uncemented acetabular cup in acetabular revision arthroplasty%生物学固定骨小梁金属杯在髋臼翻修中的应用

    Institute of Scientific and Technical Information of China (English)

    徐卫东; 陈刚; 张东华

    2009-01-01

    前后X射线平片显示无假体移位下沉等不稳迹象,骨小梁金属杯周围骨质向内长入.本组患者无置换后并发症发生,截至最后1次随访有14例行走时无疼痛,2例轻度疼痛伴轻度跛行.未出现症状性深静脉血栓或神经损伤.无需要再度翻修病例.结论:初次固定人工髋臼杯失败的病例,若无骨缺损,翻修时使用骨小梁金属杯可以获得良好的早期效果.%BACKGROUND: Biological fixation refers to the treatment of coarse or porous prosthetic surface. It is favorable to "bone ingrowth" prosthesis to achieve long-term stability. Porous tantalum is the latest scientific product that appears suitable to prosthetic surface owing to its porous feature and has been attracting a great deal attention.OBJECTIVE: To investigate the therapeutic efficacy of a porous tantalum uncemented acetabular cup in acetabular revision arthroplasty.DESIGN, TIME AND SETTING: A retrospective case analysis was performed at the Department of Orthopedics, Changhai Hospital, Second Military Medical University of Chinese PLA between April and November 2006.PARTICIPANTS/MATERIALS: Sixteen patients (16 hips), 7 males and 9 females, aged 54-81 years old, who received treatment at the Department of Orthopedics, Changhai Hospital, Second Military Medical University of Chinese PLA were included in this study. Of these patients, 2 suffered from femoral neck fracture, 6 from aseptic femoral head necrosis, and 8 from osteoarthritis. Trabecular metal cup (Zimmer, Warsaw, Indiana) provided a titanium alloy bottom layer and porous tantalum-coated surface, which was realized by technical combination of bone trabecular tantalum and titanium alloy. The prosthesis contained an ultrahigh modulus polyethylene lining.METHODS: All patients underwent acetabular revision with modular porous tantalum uncemented acetabular cup. Prior to replacement, acetabular defects and femoral prosthesis were evaluated. A posterolateral approach of hip joint was made. Following

  17. Cementless Titanium Mesh Fixation of Osteoporotic Burst Fractures of the Lumbar Spine Leads to Bony Healing: Results of an Experimental Sheep Model

    Science.gov (United States)

    Roepenack, Paula; Roesner, Jan; Herlyn, Philipp Karl Ewald; Martin, Heiner; Reichel, Martin; Rotter, Robert; Vollmar, Brigitte; Mittlmeier, Thomas; Gradl, Georg

    2016-01-01

    Introduction. Current treatment strategies for osteoporotic vertebral compression fractures (VCFs) focus on cement-associated solutions. Complications associated with cement application are leakage, embolism, adjacent fractures, and compromise in bony healing. This study comprises a validated VCF model in osteoporotic sheep in order to (1) evaluate a new cementless fracture fixation technique using titanium mesh implants (TMIs) and (2) demonstrate the healing capabilities in osteoporotic VCFs. Methods. Twelve 5-year-old Merino sheep received ovariectomy, corticosteroid injections, and a calcium/phosphorus/vitamin D-deficient diet for osteoporosis induction. Standardized VCFs (type AO A3.1) were created, reduced, and fixed using intravertebral TMIs. Randomly additional autologous spongiosa grafting (G1) or no augmentation was performed (G2, n = 6 each). Two months postoperatively, macroscopic, micro-CT and biomechanical evaluation assessed bony consolidation. Results. Fracture reduction succeeded in all cases without intraoperative complications. Bony consolidation was proven for all cases with increased amounts of callus development for G2 (58.3%). Micro-CT revealed cage integration. Neither group showed improved results with biomechanical testing. Conclusions. Fracture reduction/fixation using TMIs without cement in osteoporotic sheep lumbar VCF resulted in bony fracture healing. Intravertebral application of autologous spongiosa showed no beneficial effects. The technique is now available for clinical use; thus, it offers an opportunity to abandon cement-associated complications. PMID:27019848

  18. Cementless Titanium Mesh Fixation of Osteoporotic Burst Fractures of the Lumbar Spine Leads to Bony Healing: Results of an Experimental Sheep Model.

    Science.gov (United States)

    Eschler, Anica; Roepenack, Paula; Roesner, Jan; Herlyn, Philipp Karl Ewald; Martin, Heiner; Reichel, Martin; Rotter, Robert; Vollmar, Brigitte; Mittlmeier, Thomas; Gradl, Georg

    2016-01-01

    Introduction. Current treatment strategies for osteoporotic vertebral compression fractures (VCFs) focus on cement-associated solutions. Complications associated with cement application are leakage, embolism, adjacent fractures, and compromise in bony healing. This study comprises a validated VCF model in osteoporotic sheep in order to (1) evaluate a new cementless fracture fixation technique using titanium mesh implants (TMIs) and (2) demonstrate the healing capabilities in osteoporotic VCFs. Methods. Twelve 5-year-old Merino sheep received ovariectomy, corticosteroid injections, and a calcium/phosphorus/vitamin D-deficient diet for osteoporosis induction. Standardized VCFs (type AO A3.1) were created, reduced, and fixed using intravertebral TMIs. Randomly additional autologous spongiosa grafting (G1) or no augmentation was performed (G2, n = 6 each). Two months postoperatively, macroscopic, micro-CT and biomechanical evaluation assessed bony consolidation. Results. Fracture reduction succeeded in all cases without intraoperative complications. Bony consolidation was proven for all cases with increased amounts of callus development for G2 (58.3%). Micro-CT revealed cage integration. Neither group showed improved results with biomechanical testing. Conclusions. Fracture reduction/fixation using TMIs without cement in osteoporotic sheep lumbar VCF resulted in bony fracture healing. Intravertebral application of autologous spongiosa showed no beneficial effects. The technique is now available for clinical use; thus, it offers an opportunity to abandon cement-associated complications. PMID:27019848

  19. Computed tomography arthrography with traction in the human hip for three-dimensional reconstruction of cartilage and the acetabular labrum

    International Nuclear Information System (INIS)

    Aim: To develop and demonstrate the efficacy of a computed tomography arthrography (CTA) protocol for the hip that enables accurate three-dimensional reconstructions of cartilage and excellent visualization of the acetabular labrum. Materials and methods: Ninety-three subjects were imaged (104 scans); 68 subjects with abnormal anatomy, 11 patients after periacetabular osteotomy surgery, and 25 subjects with normal anatomy. Fifteen to 25 ml of contrast agent diluted with lidocaine was injected using a lateral oblique approach. A Hare traction splint applied traction during CT. The association between traction force and intra-articular joint space was assessed qualitatively under fluoroscopy. Cartilage geometry was reconstructed from the CTA images for 30 subjects; the maximum joint space under traction was measured. Results: Using the Hare traction splint, the intra-articular space and boundaries of cartilage could be clearly delineated throughout the joint; the acetabular labrum was also visible. Dysplastic hips required less traction (∼5 kg) than normal and retroverted hips required (>10 kg) to separate the cartilage. An increase in traction force produced a corresponding widening of the intra-articular joint space. Under traction, the maximum width of the intra-articular joint space during CT ranged from 0.98–6.7 mm (2.46 ± 1.16 mm). Conclusions: When applied to subjects with normal and abnormal hip anatomy, the CTA protocol presented yields clear delineation of the cartilage and the acetabular labrum. Use of a Hare traction splint provides a simple, cost-effective method to widen the intra-articular joint space during CT, and provides flexibility to vary the traction as required. - Highlights: • We present a hip CTA protocol to clearly delineate the intra-articular space. • A Hare traction splint provides a simple, cost-effective way to apply traction. • The required traction force depends on individual hip morphology. • The traction force

  20. Abordagem cirúrgica inédita para denervação acetabular em cães A new surgical approach to acetabular denervation in dogs

    OpenAIRE

    Cássio R.A. Ferrigno; Alexandre Schmaedecke; Vanessa C.M. Ferraz

    2007-01-01

    Este artigo tem por objetivo demonstrar nova abordagem cirúrgica para denervação seletiva das fibras sensitivas do periósteo acetabular, para tratamento da displasia coxo femoral em cães, conduzidas em 189 articulações. Para tanto, é descrita abordagem da região cranial e dorso-lateral do acetábulo de cães por incisão em forma de meia lua de aproximadamente de três centímetros de extensão, iniciando trocânter maior do fêmur e em direção ao corpo do ílio. Após rebatimento dorsal do músculo glú...

  1. CT false-profile view of the hip: a reproducible method of measuring anterior acetabular coverage using volume CT data

    Energy Technology Data Exchange (ETDEWEB)

    Needell, Steven D.; Borzykowski, Ross M. [Boca Radiology Group, Boca Raton, FL (United States); Carreira, Dominic S.; Kozy, John [Broward Health Orthopedics and Sports Medicine, Fort Lauderdale, FL (United States)

    2014-11-15

    To devise a simple, reproducible method of using CT data to measure anterior acetabular coverage that results in values analogous to metrics derived from false-profile radiographs. Volume CT images were used to generate simulated false-profile radiographs and cross-sectional false-profile views by angling a multiplanar reformat 115 through the affected acetabulum relative to a line tangential to the posterior margin of the ischial tuberosities. The anterolateral margin of the acetabulum was localized on the CT false-profile view corresponding with the cranial opening of the acetabular roof. Anterior center edge angle (CEA) was measured between a vertical line passing through the center of the femoral head and a line connecting the center of the femoral head with the anterior edge of the condensed line of the acetabulum (sourcil). Anterior CEA values measured on CT false-profile views of 38 symptomatic hips were compared with values obtained on simulated and projection false-profile radiographs. The CT false-profile view produces a cross-sectional image in the same obliquity as false-profile radiographs. Anterior CEA measured on CT false-profile views were statistically similar to values obtained with false-profile radiographs. CT technologists quickly mastered the technique of generating this view. Inter-rater reliability indicated this method to be highly reproducible. The CT false-profile view is simple to generate and anterior CEA measurements derived from it are similar to those obtained using well-positioned false-profile radiographs. Utilization of CT to assess hip geometry enables precise control of pelvic inclination, eliminates projectional errors, and minimizes limitations of image quality inherent to radiography. (orig.)

  2. CT false-profile view of the hip: a reproducible method of measuring anterior acetabular coverage using volume CT data

    International Nuclear Information System (INIS)

    To devise a simple, reproducible method of using CT data to measure anterior acetabular coverage that results in values analogous to metrics derived from false-profile radiographs. Volume CT images were used to generate simulated false-profile radiographs and cross-sectional false-profile views by angling a multiplanar reformat 115 through the affected acetabulum relative to a line tangential to the posterior margin of the ischial tuberosities. The anterolateral margin of the acetabulum was localized on the CT false-profile view corresponding with the cranial opening of the acetabular roof. Anterior center edge angle (CEA) was measured between a vertical line passing through the center of the femoral head and a line connecting the center of the femoral head with the anterior edge of the condensed line of the acetabulum (sourcil). Anterior CEA values measured on CT false-profile views of 38 symptomatic hips were compared with values obtained on simulated and projection false-profile radiographs. The CT false-profile view produces a cross-sectional image in the same obliquity as false-profile radiographs. Anterior CEA measured on CT false-profile views were statistically similar to values obtained with false-profile radiographs. CT technologists quickly mastered the technique of generating this view. Inter-rater reliability indicated this method to be highly reproducible. The CT false-profile view is simple to generate and anterior CEA measurements derived from it are similar to those obtained using well-positioned false-profile radiographs. Utilization of CT to assess hip geometry enables precise control of pelvic inclination, eliminates projectional errors, and minimizes limitations of image quality inherent to radiography. (orig.)

  3. The diagnostic value of direct CT arthrography using MDCT in the evaluation of acetabular labral tear: with arthroscopic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Yong-Chan; Kim, Jae Yoon [Chung-Ang University College of Medicine, Department of Orthopaedic Surgery, Seoul (Korea, Republic of); Choi, Jung-Ah; Lee, Guen Young; Kang, Heung Sik [Seoul National University Bundang Hospital, Departments of Radiology, Seoul National University College of Medicine, 166 Gumi-ro, Bundang-gu, Seongnam (Korea, Republic of); Lee, Young-Kyun; Koo, Kyung-Hoi [Seoul National University Bundang Hospital, Orthopaedic Surgery, Seoul National University College of Medicine, Seongnam (Korea, Republic of)

    2013-05-15

    The purpose of this study was first, to determine the sensitivity, specificity, and accuracy of MDCT arthrography (CTA) for the diagnosis of acetabular labral tear and sulcus; second, to correlate tear types using the Lage classification system on CTA compared with the arthroscopic classification; and third, to correlate CTA localization with arthroscopic localization. Direct CTA was performed using 16- or 64-slice MDCT in 126 hips (124 patients) who had chronic groin pain and positive impingement test. Images were reviewed and evaluated by two experienced musculoskeletal radiologists preoperatively. CTA findings were compared with arthroscopic findings in 58 hips (56 patients) under consensus by two orthopedic surgeons. Forty-one of the 58 hips were diagnosed as labral tears on CT arthrography. Forty-three of the 58 hips were shown to have a labral tear on arthroscopy. Sensitivity, specificity, and accuracy for detecting labral tear and sulcus by CTA were 90.7%, 86.7%, and 89.7%, and 93.8%, 97.6% and 96.6% respectively for observer 1, and 90.7% and 80.0%, 87.9% and 87.5%, 95.2%, and 93.1 % respectively for observer 2. Thirty-five out of 41 hips (85%) that were diagnosed with labral tear on CTA correlated substantially with arthroscopic Lage classification (kappa coefficient = 0.65). CTA and arthroscopic findings showed similar distribution patterns of the tears with most lesions located in antero- and postero-superior areas (p = 0.013). Direct CT arthrography using MDCT may be a useful diagnostic technique in the detection of acetabular labral tear. (orig.)

  4. Assessment of Accuracy and Reliability in Acetabular Cup Placement Using an iPhone/iPad System.

    Science.gov (United States)

    Kurosaka, Kenji; Fukunishi, Shigeo; Fukui, Tomokazu; Nishio, Shoji; Fujihara, Yuki; Okahisa, Shohei; Takeda, Yu; Daimon, Takashi; Yoshiya, Shinichi

    2016-07-01

    Implant positioning is one of the critical factors that influences postoperative outcome of total hip arthroplasty (THA). Malpositioning of the implant may lead to an increased risk of postoperative complications such as prosthetic impingement, dislocation, restricted range of motion, polyethylene wear, and loosening. In 2012, the intraoperative use of smartphone technology in THA for improved accuracy of acetabular cup placement was reported. The purpose of this study was to examine the accuracy of an iPhone/iPad-guided technique in positioning the acetabular cup in THA compared with the reference values obtained from the image-free navigation system in a cadaveric experiment. Five hips of 5 embalmed whole-body cadavers were used in the study. Seven orthopedic surgeons (4 residents and 3 senior hip surgeons) participated in the study. All of the surgeons examined each of the 5 hips 3 times. The target angle was 38°/19° for operative inclination/anteversion angles, which corresponded to radiographic inclination/anteversion angles of 40°/15°. The simultaneous assessment using the navigation system showed mean±SD radiographic alignment angles of 39.4°±2.6° and 16.4°±2.6° for inclination and anteversion, respectively. Assessment of cup positioning based on Lewinnek's safe zone criteria showed all of the procedures (n=105) achieved acceptable alignment within the safe zone. A comparison of the performances by resident and senior hip surgeons showed no significant difference between the groups (P=.74 for inclination and P=.81 for anteversion). The iPhone/iPad technique examined in this study could achieve acceptable performance in determining cup alignment in THA regardless of the surgeon's expertise. [Orthopedics. 2016; 39(4):e621-e626.]. PMID:27322169

  5. Two-stage total hip arthroplasty for complex pelvic abnormalities: Example of hip arthrodesis conversion with concomitant treatment of pelvic and acetabular non-union.

    Science.gov (United States)

    Jacquot, A; Goetzmann, T; Jullion, S; Sirveaux, F; Molé, D; Roche, O

    2016-06-01

    Hip prosthesis implantation requires a stable pelvic foundation, which may be lacking in patients with complex pelvic abnormalities (e.g., arthrodesis conversion, tumour excision, or revision with large bony defects). Many reconstructive options exist for these situations, but their outcomes vary with the initial amount of bone loss and with the technique used. We describe a two-stage arthroplasty technique (acetabular cup first, then femoral stem) and report its use in a case of arthrodesis conversion with concomitant treatment of pelvic and acetabular non-union. Clinical and radiological outcomes after 5 years are reported. This procedure can be adapted to the most complex cases of pelvic reconstruction. PMID:27052938

  6. Abordagem cirúrgica inédita para denervação acetabular em cães A new surgical approach to acetabular denervation in dogs

    Directory of Open Access Journals (Sweden)

    Cássio R.A. Ferrigno

    2007-02-01

    Full Text Available Este artigo tem por objetivo demonstrar nova abordagem cirúrgica para denervação seletiva das fibras sensitivas do periósteo acetabular, para tratamento da displasia coxo femoral em cães, conduzidas em 189 articulações. Para tanto, é descrita abordagem da região cranial e dorso-lateral do acetábulo de cães por incisão em forma de meia lua de aproximadamente de três centímetros de extensão, iniciando trocânter maior do fêmur e em direção ao corpo do ílio. Após rebatimento dorsal do músculo glúteo médio, secciona-se parcialmente a inserção do m. glúteo profundo para acesso às regiões citadas. Com auxílio de cureta foi removido, em todos os pacientes, periósteo na margem acetabular cranial e dorso lateral, até a exposição da cortical óssea. Em todos os animais foi possível a abordagem, tanto da face cranial como também acesso para a curetagem da face dorsal do acetábulo, com a técnica descrita, com incisão de pele de aproximadamente 3,2cm. A curetagem da porção cranial do acetábulo foi, em todos os casos realizados, sem visualização do osso, mas de fácil confecção e sem intercorrências de lesão de nervos ou músculos. Em todas as abordagens foi possível visualizar a cápsula articular da articulação coxo femoral, e em nenhum dos animais esta estrutura foi incisada por erro de técnica. Conclui-se que a abordagem cirúrgica descrita no presente trabalho é factível para este tipo de procedimento cirúrgico em cães, promovendo acesso adequado, com mínima invasão e sem complicações de qualquer natureza.The purpose of this study is to demonstrate a new surgical approach for the selective denervation of the sensitive fibers of the acetabular periosteum, for the treatment of hip dysplasia in dogs, conducted in 189 joints.The surgical approach of the cranial and dorso-lateral regions of the acetabular joint in dogs, by moon-shaped incision of approximately 3cm in extension, starting from the

  7. Rifampicin-fosfomycin coating for cementless endoprostheses: antimicrobial effects against methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA).

    Science.gov (United States)

    Alt, Volker; Kirchhof, Kristin; Seim, Florian; Hrubesch, Isabelle; Lips, Katrin S; Mannel, Henrich; Domann, Eugen; Schnettler, Reinhard

    2014-10-01

    New strategies to decrease infection rates in cementless arthroplasty are needed, especially in the context of the growing incidence of methicillin-resistant Staphylococcus aureus (MRSA) infections. The purpose of this study was to investigate the antimicrobial activity of a rifampicin-fosfomycin coating against methicillin-sensitive Staphylococcus aureus (MSSA) and MRSA in a rabbit infection prophylaxis model. Uncoated or rifampicin-fosfomycin-coated K-wires were inserted into the intramedullary canal of the tibia in rabbits and contaminated with an inoculation dose of 10(5) or 10(6) colony-forming units of MSSA EDCC 5055 in study 1 and MRSA T6625930 in study 2, respectively. After 28days the animals were killed and clinical, histological and microbiological assessment, including pulse-field gel electrophoresis, was conducted. Positive culture growth in agar plate testing and/or clinical signs and/or histological signs were defined positive for infection. Statistical evaluation was performed using Fisher's exact test. Both studies showed a statistically significant reduction of infection rates for rifampicin-fosfomycin-coated implants compared to uncoated K-wires (P=0.015). In both studies none of the 12 animals that were treated with a rifampicin-fosfomycin-coated implant showed clinical signs of infection or a positive agar plate testing result. In both studies, one animal of the coating group showed the presence of sporadic bacteria with concomitant inflammatory signs in histology. The control groups in both studies exhibited an infection rate of 100% with clear clinical signs of infection and positive culture growth in all animals. In summary, the rifampicin-fosfomycin-coating showed excellent antimicrobial activity against both MSSA and MRSA, and therefore warrants further clinical testing. PMID:24948548

  8. No red cell alloimmunization or change of clinical outcome after using fresh frozen cancellous allograft bone for acetabular reconstruction in revision hip arthroplasty: a follow up study

    Directory of Open Access Journals (Sweden)

    Mittag Falk

    2012-09-01

    Full Text Available Abstract Background Possible immunization to blood group or other antigens and subsequent inhibition of remodeling or incorporation after use of untreated human bone allograft was described previously. This study presents the immunological, clinical and radiological results of 30 patients with acetabular revisions using fresh frozen non-irradiated bone allograft. Methods AB0-incompatible (donor-recipient bone transplantation was performed in 22 cases, Rh(D incompatible transplantation in 6 cases. The mean follow up of 23 months included measuring Harris hip score and radiological examination with evaluation of remodeling of the bone graft, implant migration and heterotopic ossification. In addition, all patients were screened for alloimmunization to Rh blood group antigens. Results Compared to the whole study group, there were no differences in clinical or radiological measurements for the groups with AB0- or Rh(D-incompatible bone transplantation. The mean Harris Hip Score was 80.6. X-rays confirmed total remodeling of all allografts with no acetabular loosening. At follow up, blood tests revealed no alloimmunization to Rh blood group donor antigens. Conclusions The use of fresh frozen non-irradiated bone allograft in acetabular revision is a reliable supplement to reconstruction. The risk of alloimmunization to donor-blood group antigens after AB0- or Rh-incompatible allograft transplantation with a negative long-term influence on bone-remodeling or the clinical outcome is negligible.

  9. An extended posterior approach to the hip and pelvis for complex acetabular reconstruction that preserves the gluteal muscles and their neurovascular supply.

    Science.gov (United States)

    Solomon, L B; Hofstaetter, J G; Bolt, M J; Howie, D W

    2014-01-01

    We investigated the detailed anatomy of the gluteus maximus, gluteus medius and gluteus minimus and their neurovascular supply in 22 hips in 11 embalmed adult Caucasian human cadavers. This led to the development of a surgical technique for an extended posterior approach to the hip and pelvis that exposes the supra-acetabular ilium and preserves the glutei during revision hip surgery. Proximal to distal mobilisation of the gluteus medius from the posterior gluteal line permits exposure and mobilisation of the superior gluteal neurovascular bundle between the sciatic notch and the entrance to the gluteus medius, enabling a wider exposure of the supra-acetabular ilium. This technique was subsequently used in nine patients undergoing revision total hip replacement involving the reconstruction of nine Paprosky 3B acetabular defects, five of which had pelvic discontinuity. Intra-operative electromyography showed that the innervation of the gluteal muscles was not affected by surgery. Clinical follow-up demonstrated good hip abduction function in all patients. These results were compared with those of a matched cohort treated through a Kocher-Langenbeck approach. Our modified approach maximises the exposure of the ilium above the sciatic notch while protecting the gluteal muscles and their neurovascular bundle. PMID:24395310

  10. Preliminary results of a randomized trial comparing 400 cGy vs 700 cGy as an adjuvant to prevent heterotopic ossification after total hip arthroplasty

    International Nuclear Information System (INIS)

    Purpose/Objective: We report our preliminary results of a randomized trial comparing one single dose of 400 cGy versus 700 cGy given postoperatively in an attempt to prevent heterotopic ossification after total hip arthroplasty. Materials and Methods: From 09/1993 and 05/1996, over 800 total hip replacements were performed at our hospital. From this group of patients, 120 hips in 114 high-risk patients (14%) were enrolled in a randomized trial to determine if 400 cGy (Group A) is as efficacious as 700 cGy (Group B) in preventing heterotopic ossification. In Group A, there were 42 males (46 hips) and 12 females (12 hips) with a mean age of 60 (range 41-79); with 18 primary cementless femoral components (33%), 30 primary cemented stems (55%) and 10 revisions. In Group B, there were 30 males (32 hips) and 30 females (31 hips) with a median age of 59 (range 41-85); with 12 primary cementless femoral components (20%), 44 primary cemented stems (73%) and 6 revisions. All acetabular components were of the cementless type. Patients were randomized to receive either 400 cGy or 700 cGy in one fraction. Radiotherapy is given within 48 hours post-operatively using paired anterior and posterior fields, with blocking of the cementless acetabular component and the femoral component. Results: All 114 patients were available for a minimum follow-up of 6 months (range 6-30 months). None of the arthroplasties has failed at the latest follow-up. There were no radiation therapy complications noted. Statistical analysis revealed no difference in the distribution of patients in either group according to age, sex, primary or revision arthroplasty, cemented or cementless femoral component fixation, preoperative heterotopic ossification risk, or surgical approach. Of the 58 hips in Group A, heterotopic ossification was graded as Grade 0 in 24 hips, Grade I in 10 hips, Grade II in 18 hips, Grade III in 6 hips, with no cases of Grade IV. Of the 63 hips in Group B, heterotopic ossification was

  11. Prevalence of the acetabular sublabral sulcus at MR arthrography in patients under 17 years of age: does it exist?

    Energy Technology Data Exchange (ETDEWEB)

    Magerkurth, Olaf [University of Michigan, Department of Radiology, Ann Arbor, MI (United States); Hospital Baden, Department of Radiology, Baden (Switzerland); Jacobson, Jon A.; Morag, Yoav; Fessell, David [University of Michigan, Department of Radiology, Ann Arbor, MI (United States); Bedi, Asheesh; Sekiya, Jon K. [University of Michigan, Department of Orthopedic Surgery, Ann Arbor, MI (United States)

    2015-04-18

    To retrospectively determine characteristics of contrast-filled acetabular labral clefts in patients under the age of 17 years at MR arthrography (Mra) correlated with arthroscopy, which may impact the thinking regarding the existence of a sublabral sulcus. After IRB approval, 41 patients under the age of 17 who had MRa were identified. The following observations of contrast-filled clefts were assessed: (1) presence/absence, (2) location, (3) depth, (4) abnormal signal within the labrum and (5) shape (linear, gaping, complex). Fisher's exact and the Wilcoxon matched-pairs signed-rank test were performed. Interreader agreement was calculated with Cohen's k. Reader 1 found clefts in 41 %. Depth was less than half in 6 %, more than half in 65 % and full thickness in 29 %. Shape was linear in 53 %, gaping in 18 % and complex in 29 %. Signal changes occurred in 88 %. Reader 2 found clefts in 29 %. Depth was less than half in 17 %, more than half in 58 % and full thickness in 25 %. Shape was linear in 50 %, gaping in 42 % and complex in 17 %. Signal changes occurred in 50 %. None of the clefts fulfilled the criteria for a sublabral sulcus at MRa and arthroscopy. None of the clefts found in our subjects under the age of 17 years met the MRa and arthroscopy criteria for a sublabral sulcus, which supports the theory that such clefts represent labral tears. (orig.)

  12. Palliative surgery for acetabular metastasis with pathological central dislocation of the hip joint after radiation therapy. A case report

    International Nuclear Information System (INIS)

    Orthopedic surgery for bone metastases is mainly a palliative treatment. Pathological central dislocation of the hip joint secondary to osteonecrosis of acetabular metastasis after radiation therapy brings severe suffering to cancer patients. We performed minimally invasive palliative surgery for an elderly woman, and excellent pain relief was achieved. An 80-year-old female suffering from right hip pain was referred to our hospital. She had undergone surgery for lung cancer 5 years previously and her right acetabulum was subsequently affected by metastasis. With the aim of controlling the metastasis, radiation therapy was performed. Two years later, pathological central dislocation of the hip joint occurred with sudden onset of severe pain, and she was unable to maintain a sitting position and became bedridden. After she was referred to our hospital, we created an intentional pseudarthrosis in the femoral neck for palliation. After the surgery, excellent pain relief and remarkably improved mobility were achieved during her limited remaining lifetime. In this report, we introduce a novel method of producing a pseudarthrosis in the femoral neck for pathological dislocation. This procedure is a minimally invasive treatment and an alternative option for palliative surgery for pathological dislocation of the hip joint due to osteonecrosis after radiation therapy. (author)

  13. Estudio de la función del rodete acetabular en la biomecánica de la cadera: estudio cadavérico de la repercusión de la lesión y la reparación del rodete acetabular en la cinética articular de la cadera

    OpenAIRE

    Tey Pons, Marc

    2015-01-01

    Trabajo experimental en espécimen de cadera para valorar la repercusión de la lesión labral, parcial o completa, en la distribución de cargas de la superficie acetabular, así como el papel de la reconstrucción labral por reanclaje al reborde acetabular en la misma. Este trabajo implica el diseño y desarrollo previo de una bancada de prueba, el uso de tecnología de sensores piezoeléctricos para medir la presión intraarticular y la medición dinámica de las mismas en cinco especímenes anatómi...

  14. Denervação acetabular cranial e dorsal no tratamento da displasia coxofemoral em cães: 360 dias de evolução de 97 casos Cranial and dorsal acetabular denervation technique in treatment of hip dysplasia in dogs: 360 days evaluation of 97 cases

    OpenAIRE

    Cássio R.A. Ferrigno; Alexandre Schmaedecke; Leda M. de Oliveira; Raquel S. D'Ávila; Estela Y. Yamamoto; João Paulo E. Saut

    2007-01-01

    Realizou-se a pesquisa com o intuito de avaliar os resultados clínicos da denervação acetabular cranial e dorsal por curetagem em cães com displasia coxofemoral. Foram estudados, para tanto, 97 cães, sem predileção racial ou sexual, de 1-7 anos de idade, com diagnóstico clínico e radiográfico de displasia coxofemoral. Para avaliação dos resultados da técnica cirúrgica, de curetagem das fibras nervosas do periósteo acetabular cranial e dorsal, exames clínicos foram realizados no momento pré-op...

  15. Spontaneous Dissociation of Anatomic Medullary Locking A Plus (AML A Plus) Femoral Component at the Head-Neck Interface

    Science.gov (United States)

    Pande, Ketan; Leong, Juzaily Fekry; Lo, Ngai Nung

    2015-01-01

    Introduction: Innovations in the design of total hip arthroplasty components have been developed to address certain limitations with the use of standard monoblock prosthesis. With increasing use and long-term follow up, certain complications particularly related to fretting, corrosion and fatigue have been recognized. Case Report: A 31 year old active male patient presented with spontaneous dissociation of the Anatomic Medullary Locking A Plus (AML A Plus) Femoral Component at head and neck interface 10 years after surgery. At revision surgery, wear of the acetabular liner and head and neck taper was noted. Definitive treatment required complete revision of the femoral component and change of acetabular liner. Conclusion: While modularity allows change of worn out components, this case highlights the importance of various factors in avoiding this complication and the need for surgeon to be prepared to use ‘taper sleeves’ or revise the components if taper exchange fails particularly in cases with dissociation of head-neck interface which is usually associated with taper damage. PMID:27299068

  16. Achados em ressonância magnética artrográfica de indivíduos com lesão do labrum acetabular Magnetic resonance arthrographic findings in subjects with acetabular labral tears

    Directory of Open Access Journals (Sweden)

    André Luiz Almeida Pizzolatti

    2011-01-01

    Full Text Available OBJETIVO: Descrever os achados em artro RM de sujeitos com suspeita de lesão do labrum acetabular. MÉTODO: Foram analisadas 108 artro RM de quadris em 2007/2008. Dois radiologistas independentemente analisaram as imagens e foi considerada a resposta comum entre eles. Com base em seus pareceres observou-se o local e estadiamento das lesões labrais e condrais, as alterações anatômicas, e a presença de tendinite e bursite trocantérica. RESULTADO: As lesões labrais grau I ocorreram em 41% dos casos, grau II em 31%, e grau III em 29%. O IFA tipo cam foi frequente em 36% dos casos, tipo pincer em 11%, e IFA misto em 13%, nestes casos 57% apresentaram lesão labral grau III, A lesão condral grau I foi observada em 51% acetábulos, as de grau II em 13%, e grau III em 18%. CONCLUSÃO: As alterações morfológicas que provocam IFA do tipo cam foram as mais prevalentes. Em relação ao grau de lesão labral e condral foram predominantes as lesões grau I independente da presença ou do tipo de IFA, exceto em IFAs mistos onde houve predomínio de lesão labral grau III. Não foi observada uma relação entre o grau de lesão labral e condral.OBJECTIVE: To describe the MR arthrographic findings in subjects with suspected acetabular labral tears of the hip. METHOD: 108 hip MRa results were analyzed in 2007-2008. Two radiologists independently interpreted the images, and the consensual answers between them were considered for analysis. Based on their opinions, information was obtained on the location, staging of the chondral and labral lesions, anatomic alterations, and the presence of trochanteric bursitis and tendonitis. RESULTS: 1st degree labral lesions occurred in 41% of cases, 2nd degree in 31%, and 3rd degree in 29%. The cam type FAI was common in 36% of cases, pincer FAI in 11%, and mixed cam-pincer FAI in 13%; in these cases 57% had grade III labral lesions. 1st degree chondral lesions were observed in 51% of acetabulum, 2nd degree in 13

  17. Acetabular deepening in the treatment of severe canine hip dysplasia Aprofundamento do acetábulo no tratamento de displasia coxofemoral grave em cães

    Directory of Open Access Journals (Sweden)

    Paulo Iamaguti

    2009-02-01

    Full Text Available A technique to restore acetabular anatomy by deepening the acetabular cavity and reconstructing the femoral head ligament and the joint capsule was tested on nine large breed dogs with severe hip dysplasia and acute subdislocation or dislocation. The technique consisted of two phases. First, all dogs were submitted to bilateral pectinotomy. In a second surgical intervention on the same dogs the acetabulum was approached and deepened, and the femoral head ligament and the joint capsule were reconstructed. In general, within 30 days of the surgery dogs could stand on the operated member to walk. Except for two dogs, all the others recovered pelvic member locomotive ability within 60-90 days after surgery. It is concluded that acetabuloplasty is a good alternative for treatment of severe canine hip dysplasia.Uma técnica para restituir a anatomia acetabular com aprofundamento da cavidade acetabular e reconstrução do ligamento da cabeça do fêmur e da cápsula articular, foi testada em nove cães, de raças de grande porte, portadores de displasia coxofemoral grave com subluxação acentuada ou luxação. O procedimento cirúrgico foi constituído de duas fases. Inicialmente, foi realizada a pectineotomia bilateral em todos os cães. A segunda intervenção nos mesmos cães incluiu abordagem e aprofundamento do acetábulo, reconstrução do ligamento da cabeça do fêmur e da cápsula. Em geral, 30 dias após a cirurgia, os cães apoiavam o membro operado para se locomover. Com exceção de dois cães, todos os outros recuperaram a função locomotora do membro pélvico dentro de 60-90 dias. É concluído que a técnica de acetabuloplastia é uma boa alternativa para o tratamento da displasia coxofemoral grave.

  18. A Comparison of the Contact Force Distributions on the Acetabular Surface Due to Orthopedic Treatments for Developmental Hip Dysplasia.

    Science.gov (United States)

    Márquez-Flórez, Kalenia M; Silva, Octavio; Narváez-Tovar, Carlos A; Garzón-Alvarado, Diego A

    2016-07-01

    We used a three-dimensional rigid body spring model (RBSM) to compare the contact force distributions on the acetabular surface of the infant hip joint that are produced by three orthopedic treatments for developmental dysplasia of the hip (DDH). We analyzed treatments using a Pavlik harness, a generic rigid splint, and a spica cast. The joint geometry was modeled from tomography images of a 1-year-old female. The articular cartilage was modeled as linear springs connecting the surfaces of the acetabulum and the femoral head, whereas the femur and the hip bone were considered as rigid bodies. The hip muscles were modeled as tensile-only preloaded springs. The treatments with the Pavlik harness and the generic rigid splint were modeled for an infant in supine position with a hip flexion angle of 90 deg. Also, since rigid splints are often recommended when children are initiating their gait phase, we modeled the treatment with the infant in standing position. For the spica cast, we only considered the infant in standing position with a flexion angle of 0 deg, and the fixation bar at two heights: at the ankle and at the knee. In order to analyze the effect of the hip abduction angle over the contact force distribution, different abduction angles were used for all the treatments modeled. We have found that the treatments with the infant in supine position, with a flexion angle of 90 deg and abduction angles between 60 deg and 80 deg, produce a more homogenous contact force distribution compared to those obtained for the treatments with the infant in standing position. PMID:27150210

  19. Accuracy and Precision of Three-Dimensional Low Dose CT Compared to Standard RSA in Acetabular Cups: An Experimental Study

    Science.gov (United States)

    Olivecrona, Henrik; Maguire, Gerald Q.; Noz, Marilyn E.; Zeleznik, Michael P.

    2016-01-01

    Background and Purpose. The gold standard for detection of implant wear and migration is currently radiostereometry (RSA). The purpose of this study is to compare a three-dimensional computed tomography technique (3D CT) to standard RSA as an alternative technique for measuring migration of acetabular cups in total hip arthroplasty. Materials and Methods. With tantalum beads, we marked one cemented and one uncemented cup and mounted these on a similarly marked pelvic model. A comparison was made between 3D CT and standard RSA for measuring migration. Twelve repeated stereoradiographs and CT scans with double examinations in each position and gradual migration of the implants were made. Precision and accuracy of the 3D CT were calculated. Results. The accuracy of the 3D CT ranged between 0.07 and 0.32 mm for translations and 0.21 and 0.82° for rotation. The precision ranged between 0.01 and 0.09 mm for translations and 0.06 and 0.29° for rotations, respectively. For standard RSA, the precision ranged between 0.04 and 0.09 mm for translations and 0.08 and 0.32° for rotations, respectively. There was no significant difference in precision between 3D CT and standard RSA. The effective radiation dose of the 3D CT method, comparable to RSA, was estimated to be 0.33 mSv. Interpretation. Low dose 3D CT is a comparable method to standard RSA in an experimental setting. PMID:27478832

  20. Computerized tomography in evaluation of decreased acetabular and femoral anteversion; Besonderheiten bei der Bestimmung der Hueftpfannenanteversion und Schenkelhalsantetorsion durch Computertomographie

    Energy Technology Data Exchange (ETDEWEB)

    Toennis, D.; Skamel, H.J. [Institut fuer Strahlendiagnostik, Klinikum Dortmund GmbH (Germany)

    2003-09-01

    Computerized tomography has received a new importance. It has been shown that decreased anteversion of femur and acetabulum, when both have decreased angles, are causing pain and osteoarthritis of the hip joint. Operative treatment should be performed before osteoarthritis develops. Exact measurements therefore are necessary. The investigation should be performed in prone position to have the pelvis lying in a defined and normal position. Femoral torsion is measured between the transverse axis of the knee and the femoral neck. The transverse axis for measurement of the femoral anteversion is defined by a rectangular line to the sagittal plane. For evaluation of the femoral anteversion in total the angle of the condyles has to be added to the femoral neck angle when the knee is found in internal rotation. Acetabular anteversion should be measured at the level where the femoral head is still in full contact and congruence with the anterior margin of the acetabulum. (orig.) [German] Fuer die Computertomographie hat sich eine neue Aufgabe ergeben. Es hat sich gezeigt, dass verringerte Pfannenanteversion und Schenkelhalsantetorsion haeufige Ursachen von Hueftschmerz und -arthrose sind, v. a. wenn beide gegen 0 gehen. Da operative Massnahmen vor Eintreten der Arthrose ergriffen werden sollten, sind genaue Messwerte erforderlich. Die Untersuchung sollte in Bauchlage durchgefuehrt werden, um eine einheitliche und weitgehend normale Beckenkippung zu gewaehrleisten. Die Schenkelhalstorsion wird zwischen der Kniegelenk- und der Schenkelhalsachse gemessen. Zur Festlegung der Sagittalebene legt man am besten eine Mittellinie zwischen die Beckenschaufeln. Die Messung der Pfannenanteversion sollte in der Schnitthoehe erfolgen, wo die Bewegungseinschraenkung der Innenrotation auftritt. (orig.)

  1. Orientation and depth estimation for femoral components using image sensor, magnetometer and inertial sensors in THR surgeries.

    Science.gov (United States)

    Jiyang Gao; Shaojie Su; Hong Chen; Zhihua Wang

    2015-08-01

    Malposition of the acetabular and femoral component has long been recognized as an important cause of dislocation after total hip replacement (THR) surgeries. In order to help surgeons improve the positioning accuracy of the components, a visual-aided system for THR surgeries that could estimate orientation and depth of femoral component is proposed. The sensors are fixed inside the femoral prosthesis trial and checkerboard patterns are printed on the internal surface of the acetabular prosthesis trial. An extended Kalman filter is designed to fuse the data from inertial sensors and the magnetometer orientation estimation. A novel image processing algorithm for depth estimation is developed. The algorithms have been evaluated under the simulation with rotation quaternion and translation vector and the experimental results shows that the root mean square error (RMSE) of the orientation estimation is less then 0.05 degree and the RMSE for depth estimation is 1mm. Finally, the femoral head is displayed in 3D graphics in real time to help surgeons with the component positioning. PMID:26736858

  2. Denervação acetabular cranial e dorsal no tratamento da displasia coxofemoral em cães: 360 dias de evolução de 97 casos Cranial and dorsal acetabular denervation technique in treatment of hip dysplasia in dogs: 360 days evaluation of 97 cases

    Directory of Open Access Journals (Sweden)

    Cássio R.A. Ferrigno

    2007-08-01

    Full Text Available Realizou-se a pesquisa com o intuito de avaliar os resultados clínicos da denervação acetabular cranial e dorsal por curetagem em cães com displasia coxofemoral. Foram estudados, para tanto, 97 cães, sem predileção racial ou sexual, de 1-7 anos de idade, com diagnóstico clínico e radiográfico de displasia coxofemoral. Para avaliação dos resultados da técnica cirúrgica, de curetagem das fibras nervosas do periósteo acetabular cranial e dorsal, exames clínicos foram realizados no momento pré-operatório (exame inicial, e pós-operatório, nos dias dois, sete, 14, 21, 30, 60, 180 e 360. Todos os animais foram avaliados quanto à claudicação, dor à movimentação e toque, grau de atrofia muscular, sensibilidade dolorosa ao teste de Ortolani, e qualidade de vida. A denervação reduziu a claudicação, e dor à movimentação e toque à partir de dois dias de pós-operatório, reduziu atrofia muscular aos 60 dias pós-operatórios, e melhorou a qualidade de vida dos pacientes tratados, sob a ótica dos proprietários e veterinários aos 360 dias de pós-operatório. A dener-vação acetabular dorsal é técnica factível no tratamento da dor conseqüente à displasia coxofemoral em cães, com decréscimo significativo desta após dois dias da intervenção cirúrgica, aumenta qualidade de vida e proporciona maior atividade aos pacientes com proprietários satisfeitos quanto aos resultados do procedimento. A técnica cirúrgica deve incluir a curetagem das fibras nervosas do periósteo acetabular tanto da região cranial quanto dorsal.The aim was to evaluate the clinical results of cranial and dorsal acetabular denervation using curettage in dysplastic dogs. Ninty seven dogs without distinction of breed and sex, 1 to 7 years of age, were analyzed for diagnosis and treatment of hip dysplasia, based on physical examination, clinical signs and radiographic findings. For evaluation of results of the surgical denervation technique

  3. The modern, hybrid total hip arthroplasty for primary osteoarthritis at the Hospital for Special Surgery.

    Science.gov (United States)

    González Della Valle, A; Sharrock, N; Barlow, M; Caceres, L; Go, G; Salvati, E A

    2016-01-01

    We describe our technique and rationale using hybrid fixation for primary total hip arthroplasty (THA) at the Hospital for Special Surgery. Modern uncemented acetabular components have few screw holes, or no holes, polished inner surfaces, improved locking mechanisms, and maximised thickness and shell-liner conformity. Uncemented sockets can be combined with highly cross-linked polyethylene liners, which have demonstrated very low wear and osteolysis rates after ten to 15 years of implantation. The results of cement fixation with a smooth or polished surface finished stem have been excellent, virtually eliminating complications seen with cementless fixation like peri-operative femoral fractures and thigh pain. Although mid-term results of modern cementless stems are encouraging, the long-term data do not show reduced revision rates for cementless stems compared with cemented smooth stems. In this paper we review the conduct of a hybrid THA, with emphasis on pre-operative planning, surgical technique, hypotensive epidural anaesthesia, and intra-operative physiology. PMID:26733642

  4. Impaction grafting in the femur in cementless modular revision total hip arthroplasty: a descriptive outcome analysis of 243 cases with the MRP-TITAN revision implant

    Directory of Open Access Journals (Sweden)

    Wimmer Matthias D

    2013-01-01

    .1% after 8.7 years]. Radiologic evaluation showed no significant change in axial implant migration (4.3% vs. 9.3%; p = 0.19 but a significant reduction in proximal stress shielding (5.7% vs. 17.9%; p  Conclusion We present the largest analysis of the impaction grafting technique in combination with cementless distal diaphyseal stem fixation published so far. Our data provides initial evidence of improved bone regeneration after graft augmentation of metaphyseal bone defects. The data suggests that proximal metaphyseal graft augmentation is beneficial for large metaphyseal bone defects (Paprosky types IIC and III and stem diameters of 17 mm and above. Due to the limitations of a retrospective and descriptive study the level of evidence remains low and prospective trials should be conducted.

  5. Immunolocalization of anti-hsf1 to the acetabular glands of infectious schistosomes suggests a non-transcriptional function for this transcriptional activator.

    Directory of Open Access Journals (Sweden)

    Kenji Ishida

    Full Text Available Schistosomiasis is a chronically debilitating disease caused by parasitic worms of the genus Schistosoma, and it is a global problem affecting over 240 million people. Little is known about the regulatory proteins and mechanisms that control schistosome host invasion, gene expression, and development. Schistosome larvae, cercariae, are transiently free-swimming organisms and infectious to man. Cercariae penetrate human host skin directly using proteases that degrade skin connective tissue. These proteases are secreted from anucleate acetabular glands that contain many proteins, including heat shock proteins. Heat shock transcription factors are strongly conserved activators that play crucial roles in the maintenance of cell homeostasis by transcriptionally regulating heat shock protein expression. In this study, we clone and characterize the schistosome Heat shock factor 1 gene (SmHSF1. We verify its ability to activate transcription using a modified yeast one-hybrid system, and we show that it can bind to the heat shock binding element (HSE consensus DNA sequence. Our quantitative RT-PCR analysis shows that SmHSF1 is expressed throughout several life-cycle stages from sporocyst to adult worm. Interestingly, using immunohistochemistry, a polyclonal antibody raised against an Hsf1-peptide demonstrates a novel localization for this conserved, stress-modulating activator. Our analysis suggests that schistosome Heat shock factor 1 may be localized to the acetabular glands of infective cercariae.

  6. One stage total hip arthroplasty for acetabular fractures%Ⅰ期全髋关节置换治疗髋臼骨折

    Institute of Scientific and Technical Information of China (English)

    王子明; 孙红振; 王爱民; 杜全印; 吴思宇; 赵玉峰; 唐颖

    2008-01-01

    目的 探讨髋臼骨折后Ⅰ期全髋关节置换(total hip arthroplasty,THA)的手术适应证和手术方法,观察其临床疗效.方法 对11例髋臼骨折患者行Ⅰ期THA.其中前柱骨折3例,后壁骨折1例,后柱骨折2例,后柱合并后壁骨折2例,横形骨折1例,横形合并后壁骨折1例,两柱骨折1例.伤后8~37 d(平均24 d)接受THA.对新鲜髋臼骨折患者,先用重建钢板或螺钉固定骨折以恢复髋臼肇的形态,将切下的股骨头制成颗粒状或块状植于髋臼内后安置臼杯.陈旧性髋臼骨折有节段性髋臼骨缺损者,将切下的股骨头制成大块状进行髋臼内结构性植骨后再安置臼杯.结果 术后3个月完全负重,无人工关节脱位.随访时间6~45个月,平均28个月.Harris评分平均78分.髋关节屈伸平均活动度为95°.X线片示1例出现髋臼松动及骨溶解征象.结论 髋臼骨折移位明显,关节软骨面损伤严重,错过了手术复位时机,可以Ⅰ期行THA.如能创造稳定的髋臼杯结构,近期临床效果满意.%Objective To explore operative indications,methods and effect of one stage total hip arthroplasty(THA)in treatment of acetabular fractures.Methods One stage total hip arthroplasty (THA)was carried out in 11 patients with acetabular fractures including 10 males and one female(at mean age of 42.4 years)8-37 days(mean24 days)after injury.There were anterior column fractures in three patients,posterior wall fracture in one,posterior column fracture in two,posterior column fracture combined with posterior wall fracture in two,transverse fracture in one,transverse fracture combined with posterior wall fracture in one and two-column fracture in one.Fresh acetabular fractures were first fixed with reconstruction plate or screws to restore shape of acestbular wall;then,granule or bulk of resected femoral head were implanted into acetabulum posterior to placement of acetabular cup prosthesis.While for old acetabular fractures,the resected

  7. Electronic components

    CERN Document Server

    Colwell, Morris A

    1976-01-01

    Electronic Components provides a basic grounding in the practical aspects of using and selecting electronics components. The book describes the basic requirements needed to start practical work on electronic equipment, resistors and potentiometers, capacitance, and inductors and transformers. The text discusses semiconductor devices such as diodes, thyristors and triacs, transistors and heat sinks, logic and linear integrated circuits (I.C.s) and electromechanical devices. Common abbreviations applied to components are provided. Constructors and electronics engineers will find the book useful

  8. Seven-year results of a press-fit, hydroxyapatite-coated double mobility acetabular component in patients aged 65 years or older.

    Science.gov (United States)

    Fresard, Pierre-Luc; Alvherne, Charles; Cartier, Jean-Loup; Cuinet, Patrick; Lantuejoul, Jean-Pierre

    2013-05-01

    One hundred and thirty-four THA were done between 1998 and 2002 with AVANTAGE(®) Press-Fit double mobility cup. The mean age of patients was 74 ± 6 years (range 65-94 years). The mean follow-up was 5.4 years (range, 0.15-10 years). The mean preoperative Harris Hip Score was 51.3 ± 14 versus 88 ± 12, at the latest follow-up, and the mean Merle d'Aubigné hip functional score was 8 ± 3 versus 16.3 ± 2.91; patients (68 %) were alive at a mean of 7.2 years postoperatively (range, 5-10 years). Three revisions were documented for aseptic loosening. The overall survival rate at 7.2 years was 96.3 % (95 % confidence interval 92.2-100) using cup revision for aseptic loosening as the end point. PMID:23412297

  9. Roles of radiograph, magnetic resonance imaging, threedimensional computed tomography in early diagnosis of femoro-acetabular impingement in 17 cases

    Institute of Scientific and Technical Information of China (English)

    GU Gui-shan; ZHU Dong; WANG Gang; WANG Cheng-xue

    2009-01-01

    Objective: To evaluate the roles of radiograph, magnetic resonance imaging (MRI), three-dimensional computed tomography (3-D CT) in early diagnosis of femoro-acetabular impingement (FAI) in 17 cases. Methods: Plain radiographs of the pelvis, 3-D CT, and MRI of the hip were made on 17 patients with groin pain, which was worse with prolonged sitting (i.e. hip flexion). There was no history of trauma or childhood hip disorders in the patients who did not complain of any other joint problems or neurologic symptoms. All patients had positive anterior or posterior impingement test. Plain radiographs included an antero-posterior (AP) view of the hip and a cross table lateral view with slight internal rotation of the hip. CT scan was performed with the Lightspeed 16 row spiral (General Electric Company, USA) at 1.25 mm slice reconstruction. MRI scan was performed on the Siemens Avanto (Siemens Company, Germany)1.5T supraconducfion magnetic resonance meter. The CT and MRI scans were taken from 1 cm above the acetabulum to the lesser trochanter in 5 series. Results: The plain radiographs of the pelvis showed that among the 17 patients, 12 (70.59%) had "Cam" change of the femoral head, 6 (35.29%) had positive "cross-over" sign, and 17 (100%) had positive "Pincer" change of the acetabulum. The 16 row spiral CT noncontrast enhanced scan and 3-D reconstruction could discover minus femoral offset and ossification and osteophyte of the acetabulum labrum in all the 17 cases (100%). The MRI noncontrast enhanced scan could discover more fluid in the hip joint in 15 cases (88.33%), subchondral ossification in 3 cases (17.6%), and labium tears in 3 cases (17.6%). Conclusions: Plain radiographs can provide the initial mainstay for the diagnosis of FAI, 3-D CT can tell us the femoral offset, while MRI can show labrum tears in the very early stage of FAI. Basically, X-ray examination is enough for the early diagnosis of FAI, but 3-D CT and MRI may be useful for the treatment.

  10. Nuclear components

    International Nuclear Information System (INIS)

    The main features of the EPR concerning the fabrication of the reactor are: -) the size of the components, -) the modification of the design compared with classical PWR, and -) an intensive use of forging (in particular the cold and hot legs of the primary circuit are forged). This series of slides overviews the fabrication of the components for the EPR by highlighting the differences with the previous generation of reactors. 4 types of components are reviewed: the reactor vessel and internals, steam generators, primary circuit pipes, and primary coolant pumps. (A.C.)

  11. “钢筋混凝土”在髋臼重建中的应用★%Application of “reinforced concrete” in acetabular reconstruction

    Institute of Scientific and Technical Information of China (English)

    王子富; 尚希福

    2013-01-01

      背景:在全髋关节置换中,髋臼缺损很常见,为重建一个稳定、牢固的髋臼,置换过程中往往需要髋臼的重建。目的:探讨螺钉固定钛网结合骨水泥型髋臼杯在髋臼重建中应用的早期疗效。方法:纳入采用螺钉固定钛网结合骨水泥型臼杯重建髋臼髋关节翻修的患者23例。疼痛病史1-3年,术前 Harris 评分20-48分,平均34分。重建后采用 X 射线平片评价髋臼假体松动标准进行影像学评价及 Harris 评分定期随访。结果与结论:重建后随访1-3年,平均随访24个月,无脱失。重建后3个月 Harris 评分较重建前显著增高,置换后2年髋关节活动度较置换前显著增高,差异均有显著性意义(P <0.05)。2例患者下肢不等长,1例患者下蹲后出现脱位,保守治疗后好转。最后一次随访时无早期感染、脱位,无盆腔不适感。重建后随访影像学上显示无髋臼假体松动与移位,未发生钛网断裂。说明螺钉固定钛网结合骨水泥型髋臼杯治疗65岁以上髋关节翻修患者其近期疗效十分满意,后期疗效还有待于进一步随访观察。%BACKGROUND: In total hip arthroplasty, acetabular defects are common, for the reconstruction of a stable and solid acetabulum, the acetabular reconstruction is often required during the replacement process.OBJECTIVE: To investigate the early effect of the short term results of titanium mesh fixed by screws combined with a cemented acetabular cup in acetabular reconstruction. METHODS: Twenty-three patients treated with acetabular reconstruction by screw fixed titanium mesh combined with a cemented acetabular cup were selected. The pain history was 1 to 3 years. Harris scores before operation were 20-48 with an average score of 34. X-ray plain film was used to evaluate theacetabular prosthesis loosening standards after reconstruction for the radiographic evaluation and Harris score of regular fol ow

  12. Component Rhinoplasty

    OpenAIRE

    Mohmand, Muhammad Humayun; Ahmad, Muhammad

    2014-01-01

    BACKGROUND According to statistics of American Society of Plastic Surgeons, cosmetic rhinoplasty was the second most frequently performed cosmetic surgery. This study shares the experiences with component rhinoplasty. METHODS From 2004 to 2010, all patients underwent aesthetic nasal surgery were enrolled. The patients requiring only correction of septal deviation and those presenting with cleft lip nasal deformity were excluded. All procedures were performed under general anaesthesia with ope...

  13. Component Separations

    OpenAIRE

    Heller, Lior; McNichols, Colton H.; Ramirez, Oscar M.

    2012-01-01

    Component separation is a technique used to provide adequate coverage for midline abdominal wall defects such as a large ventral hernia. This surgical technique is based on subcutaneous lateral dissection, fasciotomy lateral to the rectus abdominis muscle, and dissection on the plane between external and internal oblique muscles with medial advancement of the block that includes the rectus muscle and its fascia. This release allows for medial advancement of the fascia and closure of up to 20-...

  14. Component separations.

    Science.gov (United States)

    Heller, Lior; McNichols, Colton H; Ramirez, Oscar M

    2012-02-01

    Component separation is a technique used to provide adequate coverage for midline abdominal wall defects such as a large ventral hernia. This surgical technique is based on subcutaneous lateral dissection, fasciotomy lateral to the rectus abdominis muscle, and dissection on the plane between external and internal oblique muscles with medial advancement of the block that includes the rectus muscle and its fascia. This release allows for medial advancement of the fascia and closure of up to 20-cm wide defects in the midline area. Since its original description, components separation technique underwent multiple modifications with the ultimate goal to decrease the morbidity associated with the traditional procedure. The extensive subcutaneous lateral dissection had been associated with ischemia of the midline skin edges, wound dehiscence, infection, and seroma. Although the current trend is to proceed with minimally invasive component separation and to reinforce the fascia with mesh, the basic principles of the techniques as described by Ramirez et al in 1990 have not changed over the years. Surgeons who deal with the management of abdominal wall defects are highly encouraged to include this technique in their collection of treatment options. PMID:23372455

  15. THEEMPIRICAL STUDY TO THE PATHOLOGICAL CHANGES OF ACETABULAR CHONDROCYTE IN THE DEVELOPMENTAL DISLOCATION OF THE HIP%发育性髋脱位髋臼软骨细胞病理学改变的实验研究

    Institute of Scientific and Technical Information of China (English)

    韦宜山; 刘万林; 丁良甲; 王炳海; 白锐; 李岱鹤; 赵振群

    2012-01-01

    Objective: To investigate the pathological changes of acetabular chondrocyte in the developmental dislocation of the hip( DDH). Methods: 20 rabbits of 4-week-old which female and male were not restricted had been made for the models. The back limb that the hip was flexured and the knee was extened then fixed with a plaster cast was made for DDH model group and the right side without fixationas the control group. Pelvis anteroposterior X-rays had been made on the models before the fixation and after8 - weeks fixation. The femoral head dislocation or not by shenton ' s line was discontinuity or by the femoral head was at the extabottom or extraupper quadrant of the Perkin squarse. Observing the changes of general shape of bilateral acetabular and the changes of chondrocyte, then observing the apoptosis of acetabular chondrocyte in 12 successful models. Results: Success rate of DDH models were60% ( 12/20). Hip X-ray of experimental side shown that the femoral head was dislocation toward the extabottom or extraupper quadrant of the Perkin squarse, the acetabular angle of the experimental was significantly increased than the control side(P<0. 05). The experimental side was found that the acetabulum became narrowing and fiied with soft tissue and the color of cartilage changed into dark,the chondrocytes were sparse and in a mess. Transmission electron microscopy results shown that the chromatin of acetabular chondrocytes were margination and condensation, the nuclear shape was irregular, the cytoplasmic vacuoles were present. Apoptosis rate of acetabular chondrocytes in experimental side was higher than the control side(P<0. 05). Conclusion; Excessive apoptosis of acetabular chondroctes may take part in the regulation of acetabular cartilage dysplasia in DDH.%目的:探讨发育性髋脱位(DDH)髋关节结构内髋臼软骨细胞的病理学变化.方法:选取出生4W的新西兰大耳白兔20只,雌雄兼用,采用兔后肢屈髋伸膝位管型石膏固定制作DDH

  16. Ten-year results with the Morscher press-fit cup: an uncemented, non-modular, porous-coated cup inserted without screws.

    Science.gov (United States)

    Garavaglia, Guido; Lübbeke, Anne; Barea, Christophe; Roussos, Constantinos; Peter, Robin; Hoffmeyer, Pierre

    2011-07-01

    Total hip arthroplasty (THA) with well designed cementless acetabular implants has shown excellent results. The purpose of this study was to assess our clinical and radiological outcomes using an uncemented cup. We conducted a prospective cohort study including all consecutive primary THAs performed with the Morscher press-fit cup, an uncemented non-modular acetabular component, between March 1996 and December 1998. Patients were evaluated at ten years with clinical and radiological follow-up, patient satisfaction and questionnaire assessment using the Harris hip score (HHS), Merle d'Aubigné and Postel score, the UCLA score, the 12-item short-form health survey (SF-12) and a visual analog scale. Five hundred sixty-one THAs were performed in 518 patients. At 120 months (± 7.3 months), 303 patients with 335 THAs were still available for follow-up. None of the patients had required cup revision for aseptic loosening. At ten years, the cup survivorship was 98.8% (95% CI 97.4-99.5) with cup revision for any cause as an endpoint. No radiolucencies were seen around the cups, but osteolytic defects involved 21 stems (8.3%). Mean total linear polyethylene wear was 0.9 mm. The Morscher acetabular replacement cup provides excellent results at ten years. There were no revisions for aseptic loosening of the cup, and no osteolytic defects were found around the cup. Patient satisfaction was high and the clinical results were very good. PMID:20524114

  17. Fenestration operation for treatment of acetabular parastyle fracture combined with articular facet compression and collapse of acetabular top involving weight-bearing dome%开窗法复位植骨内固定治疗髋臼前柱骨折合并臼顶区关节面压缩塌陷的临床研究

    Institute of Scientific and Technical Information of China (English)

    陈国富; 朱忠; 梁军波; 林列; 陈海啸

    2011-01-01

    Objective:To analyze the fenestration operation for treatment of acetabular parastyle fracture combined with articular facet compression and collapse of aeetabular top involving weight-bearing dome. Methods: From July 2005 to February 2007,52 cases of acetabular parastyle fracture combined with articular facet compression and collapse of acetabular top involving weight-bearing dome were treated by two methods. Among them, 24 cases were treated by fenestration operation for articular facet reduction,bone grafing,anatomical reconstruction of the acetabular papastyle with internal fixation,incuded 17 males and 7 females with an average age of(35.2±6.4) years old ;the other 28 cases were treated only anatomical reconstruction of the acetabular papastyle with internal fixation,included 19 males and 9 females with an average age of(36.4±4.8) years old.All the patients were evaluated with modified d'Aubigne-Postel clinical evaluation standard. Results:All patients gained bone healing. There were only 1 patient occurenced femoral nerve injury and recovered 2 months later. There were no other complications. All patients were followed up from 12 to 51 months (averaged in 31.5 months). According to modified d'Aubigne-Postel clinical evaluation standard, there were statistic difference between the two groups of patients in pain, walking, range of motion and total score. In fenestration operation group, the results were excellent in 13 patients, good in 9, fair in 1, poor in 1 ;in parastyle reduction group, the results were excellent in 9 patients, good in 11, fair in 6, poor in 2 (u=0.613, P<0.05 ). Conclusion: Fenestration operation for treatment of acetabular parastyle fracture combined with articular facet compression and collapse of acetabular top involving weight-bearing dome is a feasible methed for the recovery of hip joint function.%目的:探讨开窗法复位植骨内固定和单纯行前柱复位内固定治疗髋臼前柱骨折合并臼顶区关节面压

  18. Graphite components

    International Nuclear Information System (INIS)

    The reflector of the AVR reactor consists of needle coke graphite ARS/AMT made by the firm of Sigri GmbH. Although its orientation anisotropy is greater than those of materials developed in the last few years, the reflector graphite shows comparatively good dimensional stability in the conditions prevailing in the AVR reactor, as shown by tests on irradiation samples. It was also found that the strength increased. No damage was found during inspections in 1984 of the upper side and ceiling reflector. After a 20 year operating period, the graphite components of the AVR reactor should be in an excellent state. This will be possible to prove when samples are taken from the graphite reflector and examined in the context of a dismantling program. (orig.)

  19. Measurements of the posterior acetabular surface and design of a new anatomical locking plate for acetabular fractures%髋臼后表面解剖形态测量及新型解剖锁定钢板的设计

    Institute of Scientific and Technical Information of China (English)

    张里程; 张立海; 许猛; 尹鹏; 赵喆; 吕厚辰; 尹鹏滨; 唐佩福

    2014-01-01

    Objective To design a new type of anatomical locking plate which fits better the shape of posterior acetabular surface in Chinese population and presets reasonable directions of locking screws according to the measurements of the posterior acetabular surface in three dimensional (3D) reconstruction models of normal Chinese acetabulum.Methods Included in this study were CT scan data of the normal pelvis of 171 patients,100 males and 71 females with a mean of age 45.9 years (range,from 18 to 60 years).The imaging data at the.dicom format were imported into the Materiaise' s interactive medical image control system (Mimics,version 10.0) for 3D reconstruction and editing before they were saved as the STL files.Next the STL files were imported into the IMAGEWARE software (Imageware V12.1,US EDS Corporation) to set up standard points and surface of the posterior acetabular surfac e.Based on the database,we designed a new type of anatomical locking plate which could fit the shape of bone surface and preset directions of lock screws.Finally,the data were entered into a computerized numerical control digital milling machine to manufacture a real plate and screws.Results The mean acetabular diameters were 57.6 ± 2.9 mm and 52.6 ± 2.6 mm and the mean widths of the posterior acetabular wall were 40.7 ± 2.9 mm and 38.4 ± 2.4 mm for men and women,respectively,with significant differences between men and women (P < 0.05).After one-tenth of the diameter (d) of the acetabulum (d/10) was chosen as the measurement unit of the new coordinate system,the mean widths of the acetabular wall were 7.10 ±0.52 d/10 and 7.16 ±0.47 d/10 for men and women,respectively,with no significant difference between men and women (P > 0.05).The IMAGEWARE software showed that the anatomic shape of our self-designed new type of locking plate was in complete agreement of that of the posterior acetabular surface.The mean deviation of the plate from the bone surface was 3.2 ± 1.0 mm.The locking

  20. Design of ABC damage variable and positioning system for acetabular fractures and 1122 cases of multi-center statistic analysis%髋臼骨折ABC损伤变数定位系统的设计与1122例多中心研究分析

    Institute of Scientific and Technical Information of China (English)

    张春才; 苏佳灿; 曹烈虎; 徐永清; 阮墨; 陈庄洪; 黄继峰; 蔡贤华; 沈惠良; 刘利民; 王继芳; 许硕贵; 王岩; 唐佩福; 梁雨田; 王家让; 王愉思; 王振昊; 刘文德; 李文锐; 李文虎; 王序全; 禹宝庆; 周东生; 张鹏; 王仁; 王刚; 陈育岳; 丛永健; 纪方; 付青格; 刘欣伟; 章云童; 牛云飞; 王攀峰

    2011-01-01

    Objective:To design ABC damage variable and positioning system for acetabular fracture and explore the feasibility and clinical practical value of the system through the multi-center analysis of 1122 acetabular fractures. Methods: According to acetabular three-column conception, and pelvic ring lesions damage direction caused by acetabular fracture domino effect and injury degree of proximal femur joint,it defined class A as any column acetabular fracture; class B as any two-column acetabular fracture; class C as front,dome and posterior mixture acetabular fracture. Lower case English letters a,m,p represented front, dome, posterior fracture, respectively. Acetabular damage variables: 1 was simple displaced fractures; 2 was comminuted fractures; 3 was compression fractures. Pelvic ring lesions damage variables:α was sacroiliac joints or sacroiliac fracture horizontal separation deflection; β was sacroiliac joints or sacroiliac fracture vertical separation deflection; γwas pubic symphysis separation/superior and inferior ramus of pubis fracture deflection; αβγδ was compound floating damage. Proximal humerus joint damage variables: Ⅰ was femoral head fracture; Ⅱ was femoral neck fracture; Ⅲ was intertrochanteric fractures of femur; Ⅳ was Ⅰ to Ⅲ compound fracture. The ABC damage variable positioning system for acetabular fracture was made up by the above-mentioned variables. The statistics from March 1997 to February 2010 showed 1122 cases acetabular fractures with 18 cases of double side acetabular fracture and 1140 cases of acetabular fractures. The pelvics anterior-posterior view,ilium and obturator oblique view, and 2/3D-CT materials were analyzed and researched. Results: Each damage variables distribution situation in 1140 cases of acetabular fracture involved A in 237 cases (20.8%), B in 605 cases (53.1% ), C in 298 cases (26.1%);front column fracture in 808 cases (70.9%), dome fracture in 507 cases (44.5%), posterior fracture in

  1. Component Compatibility in Component Based Development

    OpenAIRE

    Dr. Hardeep Singh; Anitpal Kaur

    2014-01-01

    This paper presents a research on component compatibility in component based development. Component-based software engineering is a process that emphasizes the design and construction of computer-based systems using reusable software components. Commercial components repositories contain hundred thousand components that make component selection an extremely difficult and time expensive task. Often component selected by functional features are incompatible or the integration effort...

  2. Acompanhamento a médio prazo da reconstrução acetabular com enxerto ósseo liofilizado bovino e dispositivo de reforço Mid-term follow-up of acetabular reconstruction using bovine freeze-dried bone graft and reinforcement device

    Directory of Open Access Journals (Sweden)

    Ricardo Rosito

    2009-07-01

    Full Text Available OBJETIVO: Relatar a capacidade clínica e radiográfica de integração de enxertos ósseos liofilizados bovinos. MÉTODO: Vinte e cinco pacientes foram incluídos. O período médio de acompanhamento foi de oito anos. Os enxertos foram purificados e liofilizados. A análise clínica baseou-se no escore de Merle d'Aubigné e Postel, e critérios de pontuação estabelecidos para a osteointegração radiográfica foram usados para as análises radiográficas. RESULTADOS: Bons resultados clínicos e radiográficos foram observados em 80% e 72% dos casos, respectivamente. CONCLUSÃO: Enxertos liofilizados bovinos podem ser usados com segurança e adequadamente na revisão acetabular da artroplastia total de quadril.OBJECTIVE: To report clinical and radiographic graft incorporation capability of bovine freeze-dried bone grafts. METHODS: Twenty five patients were enrolled. The mean follow-up was eight years. Grafts were purified and freeze-dried. Clinical analysis was based on the score of Merle d'Aubigné and Postel and an established score criteria for radiographic bone incorporation was used for radiographic analyses. RESULTS: Good clinical and radiographic results were found in 80% and 72% of the cases, respectively. CONCLUSION: Bovine freeze-dried grafts can be safely and adequately used in acetabular revision in total hip arthroplasty.

  3. Radiographic evaluation of total hip arthroplasty; Radiologische Veraenderungen nach Implantation zementfreier Hueftgelenkendoprothesen

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelm, K.; Conrad, R.; Ziegler, H.; Schild, H. [Radiologische Universitaetsklinik Bonn (Germany); Reich, H. [Universitaetsklinik und Poliklinik fuer Orthopaedie, Bonn (Germany)

    1998-09-01

    Purpose: To evaluate early reliable radiographic signs of loosening in cementless total hip arthroplasty compared to clinical follow-up. Methods: Within a time interval of 5 years 89 patients with 101 hips underwent total hip arthroplasty using the Autophor 900 S-prosthesis. Clinical and radiographic follow-up were first performed retrospectively followed by a prospective investigation. Results: Radiographic evaluation showed prosthesis fixation in 93%. Loosening of the prosthesis was identified in 4 cases of the acetabular component and in 4 cases of the femoral stem. Pain was associated with radiographically detectable loosening of the cementless arthroplastic components in only two cases. Conclusion: Within a follow-up period of up to five years, loosening of cementless total hip arthroplasty occurs in about 7%. The most reliable radiographic signs of loosening are complete radiolucent zones wider than 2 mm at the bone-component interface, progressive subsidence, migration, or tilt of the component. Pain and movement disorders are not specific symptoms and do not necessarily indicate a loosening of the prosthesis. (orig.) [Deutsch] Ziel: Fruehzeitige radiologische Erkennung von aseptischen Lockerungen nach zementfreier Hueft-TEP im Vergleich zur klinisch-orthopaedischen Nachuntersuchungen. Methodik: In einem Zeitraum von 5 Jahren wurden bei 89 Patienten 101 zementfreie Hueftgelenkendoprothesen des Typs Autophor 900 S implantiert. Die roentgenologischen und klinischen Daten wurden zunaechst retrospektiv ausgewertet und nach Wiedereinbestellung der Patienten erneut prospektiv korreliert. Ergebnisse: Roentgenologisch wurde im Verlauf in 93% eine knoecherne Integration festgestellt. Eine aseptische Prothesenlockerung wurde jeweils in 4 Faellen der Prothesenschaefte bzw. der Pfannen diagnostiziert. In einem Fall lag eine Lockerung der Pfanne als auch des Prothesenschaftes vor. Die bei der klinischen Nachuntersuchung von 9 Patienten angegebenen Hueftschmerzen zeigten

  4. Analysis of bone formation on porous and calcium phosphate-coated acetabular cups: a randomised clinical [18F]fluoride PET study.

    Science.gov (United States)

    Ullmark, Gösta; Sörensen, Jens; Nilsson, Olle

    2012-01-01

    We present a study using Fluoride-Positron Emission Tomography (F-PET/CT) to analyse new bone formation in periacetabular bone adjacent to press fit cups following THA. In 16 THA (8 patients) with bilateral hip osteoarthritis simultaneous bilateral total hip arthroplasty (THA) was performed, employing electrochemically applied calcium phosphate coated (HA) cups or porous-coated (PC) cups allocated at random to compare the two sides. A reference group of 13 individuals with a normal healthy hip was used to determine 'normal' bone metabolism. [18F]fluoride -PET/CT was used to analyze bone formation adjacent to the cups 1 week, 4 months and 12 months after surgery. Clinical and radiographic evaluation was performed preoperatively, postoperatively and at 2 years. Bone forming activity had a mean of 5.71, 4.69 and 3.47 SUV around the HA- and 5.04, 4.80 and 3.50 SUV around the PC-cups at 1 week, 4 months and 12 months respectively. Normal bone metabolism was 3.68 SUV. After 1 year activity had declined to normal levels for both groups. The clinical results were good in all cases. HA coating resulted in higher uptake indicating higher bone forming activity after 1 week. F-PET/CT is a valuable tool to analyse bone formation and secondary stabilisation of an acetabular cup. PMID:22547382

  5. 发育性髋脱位髋臼软骨细胞凋亡的实验研究%The empirical study to acetabular chondrocyte apoptosis in the developmental dislocation of the hip.

    Institute of Scientific and Technical Information of China (English)

    韦宜山; 刘万林; 丁良甲; 王炳海; 白锐; 李岱鹤; 赵振群

    2012-01-01

    Objective To investigate the correlation of the apoptosis of acetabular chondrocyte and expression of Bcl-2 in the developmental dislocation of the hip ( DDH). Method 20 rabbits of 4-week-old which female and male were not restricted had been made for the models. The back limb that the hip was flex-ured and the knee was extened then fixed with a plaster cast was made for DDH model group and the right side without fixation as the control group. Pelvis anteroposterior X-rays had been made on the models before the fixation and after 8-weeks fixation. The femoral head dislocation or not by shenton' s line was discontinuity or by the femoral head was at the extabottom or extraupper quadrant of the Perkin squarse. 12 successful models were sacrificed at once. Observing the changes of general shape of bilateral acetabular and the changes of chondrocyte , then observing the apoptosis and expression of Bel - 2 of acetabular chondrocyte. Results Success rate of DDH models were 60% (12/20). Hip X-ray of experimental side shown that the superior margin of acetabu-lum was blunting, the femoral head was dislocation toward the extabottom or extraupper quadrant of the Perkin squarse, the acetabular angle of the experimental was significantly increased than the control side ( P < 0. 05 ) . The experimental side was found that the acetabulum became narrowing and fiied with soft tissue and the color of cartilage changed into dark, the chondrocytes were sparse and in a mess . Transmission electron microscopy results shown that the chromatin of acetabular chondrocytes were margination and condensation , the nuclear shape was irregular, the cytoplasmic vacuoles were present. Apoptosis rate of acetabular chondrocytes in experimental side was higher than the control side ( P < 0. 05 ) . The expression of Bcl-2 of acetabular chondrocytes in experimental side was lower than the control side ( P < 0. 05 ) , apoptosis and Bcl-2 expression of acetabular chondroctes were positive correlation in

  6. 复杂性髋臼骨析合并C型骨盆骨折的手术治疗探讨%Complexity of the acetabular fracture merger C pelvic fractures the surgical treatment of the discussion

    Institute of Scientific and Technical Information of China (English)

    田素魁; 邓庭明; 王振强; 蒋华富; 张玉兴; 陈劲松

    2011-01-01

    Objective To study the complexity of the acetabular fracture merger C pelvic fractures the surgical treatment of the method. Methods Through Mar 2002 to Nov 2007 acetabular merger between fracture patients pelvic fractures are classified according to summarize, pelvic fractures Tile classification and the acetabular Judet-Letourol classification, improved 13 cases were complexity acetabular merger fracture C pelvic fractures, all through the positive before the operation after haing electie line, buried in joint incision open reduction steel plate, screw intemal fixation, average follow-up treatment 2.4 (0.5~4 years). Results 13 patients except 1 patient wound postponed to 20 days after the healing (fat lique-faction), the others are primary healing wound patient in 2 cases, the acetabular poor fracture restoration, follow-up of 0.5~4 years, have 1 patient traumatic hip osteoarthritis pain are more frequent, lame, and another in 2 cases only pain symptoms, without a limp, and analgesia symptoms after treatment, 5 patients feeling of the ache, can bear, not influence the work and life, 5 patients feel and no obvious difference between before the injury. Conclusion Positive preoperative preparation, do as early as possible fractures internal fixation (orif is for complex fracture acetabular merger C pelvic fractures the effective treatment means, in surgical approach and operation in the specific strategies should follow the principle of individual.%目的 探讨复杂性髋臼骨折合并C型骨盆骨折的手术治疗方法.方法 通过对2002年3月~2007年11月间髋臼骨折合并骨盆骨折的病人进行分类总结,按照骨盆骨折Tile分类法和髋臼改良Judet-Letourol分类法,共有13例复杂性髋臼骨折合并C型骨盆骨折,都通过积极手术前处埋后,择期行联合切口进行切开复位钢板、螺钉内固定,平均随访治疗2.4年(0.5~4年).结果 13例病人中除1例病人部分伤口延期至术后20天愈合外(脂

  7. Biomechanics of acetabular CE angle and direction of hip joint acting force%髋臼CE角及关节作用力方向的生物力学作用

    Institute of Scientific and Technical Information of China (English)

    邬培慧; 傅明; 康焱; 张志奇; 杨子波; 廖威明

    2011-01-01

    目的 探讨髋臼CE角及关节作用力方向对髋关节生物力学的影响.方法 基于髋关节CT扫描图像,利用计算机辅助设计技术,建立一系列不同CE角的髋关节三维有限元模型,通过股骨头中心施加7种不同大小及方向的关节作用力,应用有限元非线性面-面接触分析方法,研究髋臼关节软骨内应力大小和分布情况以及股骨头位移.结果 当CE角减小时,髋臼软骨应力峰值平均值逐渐由1.70 MPa增大至7.89 MPa,应力分布区域面积逐渐减小,股骨头向关节外位移距离由0.04 mm增大至2.88 mm;对于CE角较小的髋关节,关节作用力方向趋向人体纵轴时,可不同程度增大髋臼软骨内应力峰值及股骨头位移距离.结论 髋关节CE角以及关节作用力方向是影响髋关节生物力学的两个重要因素.%Objective To study the effect of acetabular Center-edge (CE) angle and joint acting force direction on biomechanics of hip joint. Methods Three-dimensional hip joint models with different acetabular CE angles were established using computer-aided design (CAD) techniques according to the CT-scan images. Seven joint acting forces were loaded on the hip joint through the center of femur head from different directions. Stress on acetabular cartilage and displacement of femur head were studied by finite-element non-linear analysis. Results The average peak stress on acetabular cartilage increased to 7.89 MPa from 1.70 MPa, the distribution area of stress decreased gradually, and the distance from femur head displacement to the extra-hip joint increased to 2.88 mm from 0.04 mm when the acetabular CE angle was small. The vertical direction of joint acting force on hip joint with a smaller CE angle increased the peak stress on acetabular carti lage and the distance of femur head displacement. Conclusion CE angle and vertical acting force are the two important factors influencing the mechanics of hip joint.

  8. Early outcome of hip arthroscopy for acetabular labrale tears%髋臼盂唇损伤的关节镜手术

    Institute of Scientific and Technical Information of China (English)

    王卫国; 李子荣; 岳德波; 张念非; 洪闻

    2010-01-01

    Objective To investigate the clinical diagnosis and the results of arthroscopic treatment for acetabular labrale tears. Methods From November 2008 to December 2009, 21 patients with unilateral acetabular labrale tears underwent hip arthroscopy were entered in the study, including 9 males and 12 females with an average age of 37.1 years. Physical examination, X-ray examination and magnetic resonance arthrography (MRA) were carried out preoperatively to make the definite diagnosis. Of 21 cases, including labrale debridement in 14 cases, labrale debridement plus femoral osteoplasty in 5 cases and labrale repair plus osteoplasty in 2 cases. Patients were followed-up either by telephone inquiring or out-patient interview.The visual analogue scale (VAS) and Harris hip score were recorded before operation and 6 months after operation respectively. Results All 21 patients showed a positive Fadir impingement sign on the affected hips,meanwhile 15 cases showed a positive Fabir impingement sign, and positive McCarthy test was observed in 9cases. X-ray film showed 11 cases have cam type impingement, among which 6 combined with pincer type impingement. Two cases had acetabulum retroversion alone. On MRA images, signals of contrast agent infiltration in anterior superior quadrant which indicated labrale tear were observed among all cases. All labrale tears were confirmed under arthroscopy. All patients were followed up for average 11.6 months (range, 6-19).The symptoms were obviously released after operation. The VAS decreased from (5.3±1.3) preoperatively to (1.4±-0.9) 6 months postoperatively. The mean Harris hip score improved from (63±9) preoperatively to (84±10) 6 months postoperatively. All the differences had statistical significance. Conclusion Acetabular labrale injury has a close correlation with femoroacetabular impingement. Impingement test and MRA have a high sensitivity and accuracy on clinical diagnosis of labrale tears. Arthroscopic debridement, repair and

  9. The migration of femoral components after total hip replacement surgery: accuracy and precision of software-aided measurements

    Energy Technology Data Exchange (ETDEWEB)

    Decking, J. [Dept. of Orthopaedic Surgery, Univ. of Mainz School of Medicine, Mainz (Germany); Schuetz, U.; Decking, R.; Puhl, W. [Orthopaedic Dept., Univ. of Ulm, School of Medicine (Germany)

    2003-09-01

    Objective: To assess the accuracy and precision of a software-aided system to measure migration of femoral components after total hip replacement (THR) on digitised radiographs. Design and patients: Subsidence and varus-valgus tilt of THR stems within the femur were measured on digitised anteroposterior pelvic radiographs. The measuring software (UMA, GEMED, Germany) relies on bony landmarks and comparability parameters of two consecutive radiographs. Its accuracy and precision were calculated by comparing it with the gold standard in migration measurements, radiostereometric analysis (RSA). Radiographs and corresponding RSA measurements were performed in 60 patients (38-69 years) following cementless THR surgery. Results and conclusions: The UMA software measured the subsidence of the stems with an accuracy of {+-}2.5 mm and varus-valgus tilt with an accuracy of {+-}1.8 (95% confidence interval). A good interobserver and intraobserver reliability was calculated with Cronbach's alpha ranging from 0.86 to 0.97. Measuring the subsidence of THR stems within the femur is an important parameter in the diagnosis of implant loosening. Software systems such as UMA improve the accuracy of migration measurements and are easy to use on routinely performed radiographs of operated hip joints. (orig.)

  10. The migration of femoral components after total hip replacement surgery: accuracy and precision of software-aided measurements

    International Nuclear Information System (INIS)

    Objective: To assess the accuracy and precision of a software-aided system to measure migration of femoral components after total hip replacement (THR) on digitised radiographs. Design and patients: Subsidence and varus-valgus tilt of THR stems within the femur were measured on digitised anteroposterior pelvic radiographs. The measuring software (UMA, GEMED, Germany) relies on bony landmarks and comparability parameters of two consecutive radiographs. Its accuracy and precision were calculated by comparing it with the gold standard in migration measurements, radiostereometric analysis (RSA). Radiographs and corresponding RSA measurements were performed in 60 patients (38-69 years) following cementless THR surgery. Results and conclusions: The UMA software measured the subsidence of the stems with an accuracy of ±2.5 mm and varus-valgus tilt with an accuracy of ±1.8 (95% confidence interval). A good interobserver and intraobserver reliability was calculated with Cronbach's alpha ranging from 0.86 to 0.97. Measuring the subsidence of THR stems within the femur is an important parameter in the diagnosis of implant loosening. Software systems such as UMA improve the accuracy of migration measurements and are easy to use on routinely performed radiographs of operated hip joints. (orig.)

  11. No effect of additional screw fixation of a cementless, all-polyethylene press-fit socket on migration, wear, and clinical outcome.

    Science.gov (United States)

    Minten, Michiel J M; Heesterbeek, Petra J C; Spruit, Maarten

    2016-08-01

    Background and purpose - Additional screw fixation of the all-polyethylene press-fit RM cup (Mathys) has no additional value for migration, in the first 2 years after surgery. However, the medium-term and long-term effects of screw fixation remain unclear. We therefore evaluated the influence of screw fixation on migration, wear, and clinical outcome at 6.5 years using radiostereometric analysis (RSA). Patients and methods - This study involved prolonged follow-up from a previous randomized controlled trial (RCT). We analyzed RSA radiographs taken at baseline and at 1-, 2-, and 6.5-year follow-up. Cup migration and wear were assessed using model-based RSA software. Wear was calculated as translation of the femoral head model in relation to the cup model. Total translation, rotation, and wear were calculated mathematically from results of the orthogonal components. Results - 27 patients (15 with screw fixation and 12 without) were available for follow-up at 6.5 (5.6-7.2) years. Total translation (0.50 mm vs. 0.56 mm) and rotation (1.01 degrees vs. 1.33 degrees) of the cup was low, and was not significantly different between the 2 groups. Wear increased over time, and was similar between the 2 groups (0.58 mm vs. 0.53 mm). Wear rate (0.08 mm/year vs. 0.09 mm/year) and clinical outcomes were also similar. Interpretation - Our results indicate that additional screw fixation of all-polyethylene press-fit RM cups has no additional value regarding medium-term migration and clinical outcome. The wear rate was low in both groups. PMID:27299418

  12. Supporting software components production

    OpenAIRE

    Asirelli, Patrizia; Aquilino, Domenico; Inverardi, Paola

    1991-01-01

    In this paper we present an approach to the management of large-scale object-oriented applications based on a sharp distinction between the object-oriented language in which components are described and the way components are assembled into a specific application. In particular, we propose a database component schema which allows for a free development of components and permits to define at the database level all the policies connected to the grouping of components into a specific application...

  13. Structural autograft for acetabular reconstruction in total hip arthroplasty of developmental hip dysplasia%结构植骨重建髋臼在髋关节发育不良全髋置换中的应用

    Institute of Scientific and Technical Information of China (English)

    任翀旻; 张元凯; 李德强; 刘培来; 李明

    2013-01-01

    Objective To evaluate the result of bulk femoral head autograft for acetabular reconstruction in total hip arthroplasty for developmental hip dysplasia patients with severe acetabular deficiency.Methods Twenty-five patients (31 hips) with development hip dysplasia were performed with bulk femoral head autograft for the acetabular reconstruction in THA during 2005-2010.Twenty-nine hips in 23 patients were successfully followed up in average 5.1 years with mean age of 52.According to Crowe classification,19 hips in 15 patients were stage Ⅲ and 10 hips in 8 patients were stage Ⅳ.The deficient acetabula were reconstructed by bulk femoral head autograft.With bone guaranteed coverage,patients had prosthesis installed at the original level or closed level of true acetabulum.Radiographic changes and Harris score were evaluated.Results None suffered from loosening and collapse during the follow-up.One was revised for dislocation.Harris scores increased from 44 preoperative to 88 at last follow-up.Conclusion To reconstruct acetabulum at true acetabular level with satisfactory bone coverage by using bulk femoral head autograft is an effective and safe way for THA in developmental hip dysplasia.%目的 评价自体股骨头结构植骨重建髋臼在髋关节发育不良的全髋关节置换术中的效果.方法 选取2005年1月至2010年11月对髋Crowe分型在Ⅲ型和Ⅳ型的髋关节发育不良患者25例31髋,34 ~ 69岁,平均52岁;Ⅲ型15例19髋,Ⅳ型8例10髋;采用结构植骨重建髋臼的全髋关节置换术.术中行股骨头结构植骨,保证覆盖率的基础上,于真臼或近真臼水平重建髋臼并安装假体.术后行影像学检查和Harris评分.成功随访23例29髋,平均随访5.1年.结果 植骨愈合良好,无植骨塌陷,1例1髋术后脱位,所有病例无假体松动发生.术前Harris评分平均44分,术后1年平均89分,最后1次随访平均88分.结论 应用自体股骨头结构植骨,满足覆盖率前提下在真

  14. Femoral shaft and intertrochanteric fracture with ipsilateral acetabular fracture surgery%股骨干及股骨转子间骨折合并同侧髋臼骨折的手术治疗

    Institute of Scientific and Technical Information of China (English)

    赵阳; 薛朝辉; 杨凯

    2013-01-01

    目的:探讨股骨干及股骨转子间骨折合并同侧髋臼骨折的治疗方法及临床疗效。方法股骨干及股骨转子间骨折合并同侧髋臼骨折10例,均为男性;年龄23~56岁,平均34.5岁。髋臼骨折按Letournel分型,后壁伴后柱骨折6例,单纯后壁骨折2例,髋关节中心性骨折脱位2例。均行重建钢板内固定。股骨骨折行加长髓内钉固定6例;股骨干行钢板内固定,股骨转子间骨折行动力髋螺钉固定4例。结果6例均获随访,随访时间12个月~3年,平均17.2个月。骨折均临床愈合,髋关节功能根据D’Aubigne疗效评定标准:优7例,良2例,可1例。10例中漏诊2例,漏诊率20%。结论股骨干及股骨转子间骨折合并同侧髋臼骨折受伤暴力大、机制复杂漏诊率较高,应早期明确诊断,合理内固定临床疗效尚好。%Objective: Explore the femoral shaft and intertrochanteric fracture with ipsilateral acetabular fracture treatment and the clinical efficacy .Methods: Femoral shaft and intertrochanteric fracture with ipsilateral acetabular fracture 10 cases, men; age 23- 56 years old, average 34.5 years old. Letournel acetabular fractures according to type, the posterior wal with 6 cases of posterior column fracture, 2 cases of posterior wal fractures alone are line Femoral shaft,Central fracture dislocation of the hip in 2 cases; with interlocking intramedul ary nailing Example,6; femur plate fixation line, intertrochanteric fracture of femur with dynamic hip screw fixation Example 4. Results: 10 patients were fol owed up for 12 months to 36 months, an average of 17.2 months. Clinical healing of fractures, hip function according to D’Aubigne efficacy criteria: excellent 7 cases, good in 2 cases, Example 1. Example 10 in two cases of missed diagnosis, missed diagnosis rate of 20%. Conclusion: Femoral shaft and intertrochanteric fracture with ipsilateral acetabular fracture were injured in the violence

  15. 髋臼横行骨折采用前后柱拉力螺钉结合重建钢板固定疗效分析%Analysis of the Effect of the Acetabular Transverse Fracture Using the Lag Screw of the Acetabulum and the Reconstruction Plate With the Reconstruction Plate

    Institute of Scientific and Technical Information of China (English)

    张立峰; 冯卫; 包道日娜; 冬梅; 佟雁翔

    2015-01-01

    Objective To investigate the clinical effect of the application of the acetabular transverse fracture in the treatment of the acetabular fracture and the reconstruction of the plate fixation with the lag screw of the acetabulum. Methods 50 cases of patients with transverse acetabular fracture were selected,and subject to acetabular posterior column lag screw combined with reconstruction plate fixation treatment,Bleeding volume,operation time, the acetabulum repositioning and hip joint function recovery after surgical of patients were observed. Results The average operation time was 3.5 hours, the average amount of bleeding was 950ml, according to Matta reduction, 25 cases of anatomic reduction, satisfactory reduction in 21 cases, 4 cases of unsatisfactory reduction, and the excellent and good rate of hip joint function was 86.0%. Conclusion The clinical effect of the acetabular transverse fracture patients with the acetabular anterior and posterior column lag screw combined with the reconstruction plate fixation is worthy of promotion.%目的:探讨对髋臼横行骨折患者应用髋臼前后柱拉力螺钉结合重建钢板固定治疗的临床疗效。方法选取髋臼横行骨折患者50例,对其进行髋臼前后柱拉力螺钉结合重建钢板固定手术治疗,观察患者手术时出血量、手术时间等,手术治疗后患者髋臼复位情况以及髋关节功能恢复情况。结果平均手术时间为3.5小时,平均出血量为950 ml,根据 matta 复位,25例解剖复位,21例满意复位,4例复位不满意,髋关节功能优良率为86.0%。结论对髋臼横行骨折患者采取髋臼前后柱拉力螺钉结合重建钢板固定手术治疗临床疗效突出。

  16. Avaliação radiográfica da cobertura acetabular à cabeça femoral, após osteotomia tripla e aplicação de cunha sacroilíaca, em pelve de cadáveres de cães

    Directory of Open Access Journals (Sweden)

    Everton Regonato

    2009-08-01

    Full Text Available Na tentativa de evitar algumas das dificuldades associadas à osteotomia pélvica tripla (OPT, foi desenvolvido experimentalmente o método de aplicação de cunha na junção sacroilíaca para aumentar a ventroversão acetabular. O objetivo deste estudo foi aplicar as técnicas de cunha sacroilíaca e OPT em cadáveres e avaliar radiograficamente a eficácia da ventroversão acetabular. Para tal, foram utilizados 10 cadáveres de cães, adultos, com 15-25 kg. Em cada hemipelve direita foi realizada OPT com placas de 20° e 40°. Na hemipelve esquerda foram aplicadas cunhas nas articulações sacroilíacas de 20° e 40°. Avaliações radiográficas em projeções ventrodorsais foram realizadas para mensuração da cobertura acetabular à cabeça femoral nas duas técnicas. De acordo com os dados obtidos pode-se observar que não houve diferença entre a técnica de OPT e o uso de cunha sacroilíaca utilizando implantes de 20° e 40°, mas ocorreu diferença significativa (pAttempting to avoid difficulties associated to triple pelvic osteotomy (TPO, the sacroiliac wedge method was experimentally developed to increase the acetabular ventroversion. The goal of this study was to apply the techniques of sacroiliac wedge and TPO to canine cadavers and radiographically evaluate the efficacy of acetabular ventroversion. Ten cadavers of adult dogs weighting 15-25 kg were used. To each right hemipelvis the technique of TPO with 20° and 40° plates was applied. In the left hemipelvis, 20° and 40º wedges in the sacroiliac joint were applied. Radiographic evaluations in standard projections were carried out for measurement of the acetabular covering of the head of the femur in the two techniques. There was no significant differences between TPO and the use of sacroiliac wedge using implants of 20° and 40°, however a significant difference (p<0,05 could be observed before and after application of the 20° and 40° implants, as well as between those that

  17. 膝内外翻畸形时髋臼负重顶区的生物力学变化*★%Biomechanical changes in the acetabular dome region to knee joint varus and valgus

    Institute of Scientific and Technical Information of China (English)

    汤敏生; 白波; 谢诗涓; 龙浩; 刘琦; 陈艺

    2013-01-01

      背景:膝内、外翻畸形改变了膝关节的形态,除影响膝关节的功能外,还可能改变相邻关节髋关节的生物力学行为,也就是髋臼与股骨头之间的力学传导。  目的:评价不同程度膝内、外翻畸形对髋臼负重顶区的生物力学影响。  方法:取成年男性鲜尸体下肢标本3个,剔除附着的肌肉组织,保留骨膜、韧带及关节囊,通过胫骨高位截骨模拟不同程度的膝内外翻畸形。标本分为中立位组、膝内翻10°组、膝内翻20°组、膝外翻10°组和膝外翻20°组。实验中骨盆的位置选择单足站立中立位。标本通过生物力学试验机加载至50 kg,采用压敏片技术测量髋臼顶负重区的负重面积、平均应力及峰值应力。  结果与结论:髋臼顶区中立位时股胫关节面负重面积为(6.33±0.12) cm2,平均应力(3.62±0.33) MPa,峰值应力为(4.58±0.20) MPa。当膝内、外翻达10°时,髋臼顶区负重面积减少,平均应力及峰值应力有明显的增加,但差异无显著性意义(P>0.05);当膝内、外翻达20°时髋臼负重面积显著减少,平均应力峰值及应力显著增加,差异有非常显著性意义(P OBJECTIVE:To investigate the effect of different varus and valgus angle on the biomechanics of acetabular dome region. METHODS:Three lower limb specimens were col ected from adult male fresh cadaver. Al muscles and connective tissues were dissected while hip and knee periosteum, joint capsules and ligaments were preserved. The high tibial osteotomy was operated to simulate different degrees of knee varus and valgus. The specimens were divided into neutral position group, knee varus 10° group, knee varus 20° group, knee valgus 20° group and knee valgus 10° group. During the experiment, the pelves were in the single-leg standing neutral position. The specimens were loaded with 50 kg by biomechanical testing machine. The loading area, mean

  18. Reusable Component Services

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Reusable Component Services (RCS) is a super-catalog of components, services, solutions and technologies that facilitates search, discovery and collaboration in...

  19. Software component quality evaluation

    Science.gov (United States)

    Clough, A. J.

    1991-01-01

    The paper describes a software inspection process that can be used to evaluate the quality of software components. Quality criteria, process application, independent testing of the process and proposed associated tool support are covered. Early results indicate that this technique is well suited for assessing software component quality in a standardized fashion. With automated machine assistance to facilitate both the evaluation and selection of software components, such a technique should promote effective reuse of software components.

  20. Gas Quenching Small Components

    Institute of Scientific and Technical Information of China (English)

    Paul Stratton

    2004-01-01

    Gas quenching is an environmentally friendly and effective way of quenching components. However it has not been possible to apply it to small components because of the difficulties of jigging. A method of gas quenching such small components is described in which they are levitated in a confined gas stream. The method is suitable for quenching low alloy steel components that weigh between 1 and 10g.

  1. Extensively coated revision stems in proximally deficient femur: Early results in 15 patients

    Directory of Open Access Journals (Sweden)

    Marya SKS

    2008-01-01

    Full Text Available Background: Hip replacement following failed internal fixation (dynamic hip screw for intertrochanteric fractures or previous hip arthroplasty presents a major surgical challenge. Proximal fitting revision stems do not achieve adequate fixation. Distal fixation with long-stemmed extensively coated cementless implants (like the Solution™ system affords a suitable solution. We present our early results of 15 patients treated with extensively coated cementless revision stems. Materials and Methods: Fifteen patients with severely compromised proximal femora following either failed hip arthroplasty or failed internal fixation (dynamic hip screw fixation for intertrochanteric fractures were operated by the senior author over a two-year period. Eight patients had aseptic loosening of their femoral stems following cemented hip replacements, with severe thinning of their proximal cortices and impending stress fractures. Seven had secondary hip arthritis following failure of long implants for comminuted intertrochanteric or subtrochanteric femoral fractures. All patients were treated by removal of implant (cemented stems/DHS implants and insertion of long-stemmed extensively coated cementless revision (′ Solution™; DePuy, Warsaw (IN, US′ stems along with press-fit acetabular component (Duraloc Cup, DePuy, Warsaw (IN, US. All eight hip revisions needed extended trochanteric osteotomies. Results: All patients were primarily kept in bed on physiotherapy for six weeks and then gradually progressed to weight-bearing walking over the next six to eight weeks. The Harris Hip Scores and patient satisfaction were used for final evaluation. We achieved good results in the short term studied. In our first three patients (all following failed cemented total hip replacements, we resorted to cerclage wiring to hold osteotomised segments (done to facilitate stem removal. The subsequent 12 proceeded without the need for cerclage wiring. One patient had a

  2. 全髋关节置换术治疗成人髋臼发育不良继发骨性关节炎疗效分析%Analysis Curative Effect of Total Hip Arthroplasty in Treatment of Adult Acetabular Dysplasia With Bad Osteoarthritis Secondary

    Institute of Scientific and Technical Information of China (English)

    时梦猇

    2015-01-01

    Objective To observe curative effect of total hip arthroplasty in treatment of adult acetabular dysplasia with bad osteoarthritis secondary. Methods Retrospective analyzed the clinical data of total hip arthroplasty of adult acetabular dysplasia with bad osteoarthritis secondary. Results The symptoms of pain disappeared, and the body was short and the case was correct. The acetabular angle was located at 35 to 40 angle, and the CE angle of the prosthesis was more than 20 angle. No prosthesis loosening, fracture of acetabulum, handle, neurovascular injury and so on. The excellent and good rate of postoperative Harris hip score was 94.6%. Conclusion The effect of total hip arthroplasty on adult acetabular dysplasia with bad osteoarthritis secondary os obvious.%目的 观察全髋关节置换术治疗成人髋臼发育不良继发骨性关节炎疗效.方法 回顾性分析在我院接受全髋关节置换术治疗的成人髋臼发育不良继发骨性关节炎患者临床资料.结果 疼痛症状基本消失,肢体短缩情况矫正良好.髋臼角位于35°~40°,假体CE角>20°,无假体臼、柄松动、骨折、神经血管损伤等发生.患者术后Harris髋关节功能评分优良率94.6%.结论 全髋关节置换术治疗成人髋臼发育不良继发骨性关节炎疗效明显.

  3. Comparative Survival of Uncemented Acetabular Components Following Primary Total Hip Arthroplasty%初次全髋关节置换术后非骨水泥型髋臼的生存比较

    Institute of Scientific and Technical Information of China (English)

    James L. Howard; 林剑浩; Hilal Maradit Kremers; Youlonda A. Loechler; William S. Harmsen; Daniel J. Berry; Miguel E. Cabanela; Mark W. Pagnano; Robert T. Trousdale; David G. Lewallen

    2012-01-01

    背景:非骨水泥型髋臼自80年代初期问世以来,在美国的大多数髋关节置换中已逐渐成为备受青睐的假体类型.本研究的目的是比较初次全髋关节置换术后不同类型非骨水泥髋臼的生存情况.方法:研究对象为1984年1月至2004年12月间,在Mayo临床中心接受初次全髋关节置换术的患者,共7989人9584例髋关节.应用了二十种不同类型的非骨水泥髋臼部件.比较了不同类型髋臼部件的总体生存率和特殊原因(无菌性松动、磨损、骨溶解)导致翻修以外的生存率,并通过年龄和性别的比例风险回归模型进行校正.结果:珠状表面和羟基磷灰石涂层的髋臼系统的翻修风险,显著高于钛丝表面的髋臼.交联聚乙烯优于传统聚乙烯,但差异无显著性意义(高边内衬与臼杯的高翻修率显著相关,原因是无菌性松动).结论:不同类型的全髋置换非骨水泥髋臼假体之间,其远期生存情况具有显著差异.术后10至20年间初次全髋关节置换翻修的风险升高,主要原因是由于术后10年以上的聚乙烯磨损、骨溶解以及假体松动增多所致.证据等级:预后Ⅲ级.关于证据等级的描述详见投稿须知.

  4. 骨盆相关数据测量对髋臼发育不良髋臼定位的临床意义%Clinical implication of pelvic measurements on acetabular component location in developmental dysplasia of the hip

    Institute of Scientific and Technical Information of China (English)

    杭柏亚; 曲广运

    2007-01-01

    [目的]通过对中国南方50例单侧髋关节置换患者的全骨盆X线片相关数据的测量与分析,来验证JF Crowe在"Total hip replacement in congenital dislocation and dysplasia of the hip"(J.Bone Joint Surg.Am,1979,61:15-23)一文中提到的"股骨头颈交点与股骨头上缘的垂直距离跟坐骨结节下缘与髂骨最高点的垂直距离的比率是20%"的准确性,进而提出国人髋臼发育不良真臼的正确定位.目前国内外尚无新的报道.[方法]测量股骨头颈交点与股骨头上缘的垂直距离(BC),测量坐骨结节下缘与髂骨最高点的垂直距离(AD),计算BC与AD的比率.[结果]50例样本平均值为20.2%,与Crowe观察的结果吻合,其中女性为19.5%,男性为21.3%.[结论]对于髋臼发育不良或者髋关节发育不良的患者,对于真臼的定位可以按照这个比率进行正确的定位.

  5. 骨盆并髋臼骨折内固定材料的生物相容性%Materials biocompatibility in the internal fixation of pelvic fracture combined with acetabular fracture

    Institute of Scientific and Technical Information of China (English)

    高明杰; 陶杰; 周孜辉; 杜琳

    2015-01-01

    背景:骨盆骨折合并髋臼骨折多由高能量暴力伤所致,常伴严重并发症,往往需要外科内固定治疗。目的:探讨骨盆骨折合并髋臼骨折内固定治疗以及材料的生物相容性。方法:以“骨盆骨折,髋臼骨折,内固定,材料;pelvis fracture,acetabulum fracture,internal fixators, materials”为关键词,应用计算机检索2005至2014年万方数据库、清华知网数据库和PubMed数据库,选取有关骨盆骨折合并髋臼骨折内固定治疗以及材料生物相容性研究的文献,同一领域文献选择权威杂志或发表时间为近期的文章,依据纳入排除标准选取29篇文献进行归纳分析。结果与结论:对于骨盆骨折合并髋臼骨折临床多采用重建钢板或拉力螺钉内固定,常用于内固定的重建钢板材料是钛板,弹性模量接近骨的弹性模量,生物相容性好,可在置入前预先弯曲塑形,使之与骨折部位骨面相匹配。可吸收螺钉具有良好的组织相容性,无毒副反应,避免金属螺钉的电解与腐蚀,在内固定早期保持一定的强度,随着时间的推移骨折逐渐愈合,材料强度也缓慢降低,材料最终降解为水和二氧化碳,治疗效果满意。以三维重建技术定制钢板固定和微创内固定是目前骨折治疗的重大进展,临床应用前景广阔。%BACKGROUND:Pelvic fractures combined with acetabular fractures are mostly caused by high-energy violence, often accompanied by severe complications and high mortality, and surgical fixation is preferred in most cases. OBJECTIVE:To investigate the internal fixation of pelvic fracture combined with acetabular fracture and to analyze the material biocompatibility. METHODS:A computer-based search of Wanfang, CNKI and PubMed databases was performed for articles related to the internal fixation of pelvic fracture combined with acetabular fracture and material biocompatibility published

  6. Supply chain components

    Directory of Open Access Journals (Sweden)

    Vieraşu, T.

    2011-01-01

    Full Text Available In this article I will go through three main logistics components, which are represented by: transportation, inventory and facilities, and the three secondary logistical components: information, production location, price and how they determine performance of any supply chain. I will discuss then how these components are used in the design, planning and operation of a supply chain. I will also talk about some obstacles a supply chain manager may encounter.

  7. Supply chain components

    OpenAIRE

    Vieraşu, T.; Bălăşescu, M.

    2011-01-01

    In this article I will go through three main logistics components, which are represented by: transportation, inventory and facilities, and the three secondary logistical components: information, production location, price and how they determine performance of any supply chain. I will discuss then how these components are used in the design, planning and operation of a supply chain. I will also talk about some obstacles a supply chain manager may encounter.

  8. Control component retainer

    International Nuclear Information System (INIS)

    An apparatus is described for retaining an undriven control component assembly disposed in a fuel assembly in a nuclear reactor of the type having a core grid plate. The first part of the mechanism involves a housing for the control component and the second part is a brace with a number of arms that reach under the grid plate. The brace and the housing are coupled together to firmly hold the control components in place even under strong flows of th coolant

  9. SNRS component positioning systems

    International Nuclear Information System (INIS)

    This paper discusses the stationary neutron radiography system (SNRS) with respect to the component positioning systems (CPSs) and the rationale behind their design. As design work is on-going at Science Applications International Corporation, this report gives a current update of progress. The SNRS has four separate radiography bays, Bays 1 through 4. The first three bays have automated positioning systems for real-time and near real-time neutron radiography of aircraft components. Bay 4 has been designed to accommodate components from the solid rocket booster, but will be used first for film radiography of pyrotechnic components

  10. Discriminant Incoherent Component Analysis.

    Science.gov (United States)

    Georgakis, Christos; Panagakis, Yannis; Pantic, Maja

    2016-05-01

    Face images convey rich information which can be perceived as a superposition of low-complexity components associated with attributes, such as facial identity, expressions, and activation of facial action units (AUs). For instance, low-rank components characterizing neutral facial images are associated with identity, while sparse components capturing non-rigid deformations occurring in certain face regions reveal expressions and AU activations. In this paper, the discriminant incoherent component analysis (DICA) is proposed in order to extract low-complexity components, corresponding to facial attributes, which are mutually incoherent among different classes (e.g., identity, expression, and AU activation) from training data, even in the presence of gross sparse errors. To this end, a suitable optimization problem, involving the minimization of nuclear-and l1 -norm, is solved. Having found an ensemble of class-specific incoherent components by the DICA, an unseen (test) image is expressed as a group-sparse linear combination of these components, where the non-zero coefficients reveal the class(es) of the respective facial attribute(s) that it belongs to. The performance of the DICA is experimentally assessed on both synthetic and real-world data. Emphasis is placed on face analysis tasks, namely, joint face and expression recognition, face recognition under varying percentages of training data corruption, subject-independent expression recognition, and AU detection by conducting experiments on four data sets. The proposed method outperforms all the methods that are compared with all the tasks and experimental settings. PMID:27008268

  11. Scientific Software Component Technology

    Energy Technology Data Exchange (ETDEWEB)

    Kohn, S.; Dykman, N.; Kumfert, G.; Smolinski, B.

    2000-02-16

    We are developing new software component technology for high-performance parallel scientific computing to address issues of complexity, re-use, and interoperability for laboratory software. Component technology enables cross-project code re-use, reduces software development costs, and provides additional simulation capabilities for massively parallel laboratory application codes. The success of our approach will be measured by its impact on DOE mathematical and scientific software efforts. Thus, we are collaborating closely with library developers and application scientists in the Common Component Architecture forum, the Equation Solver Interface forum, and other DOE mathematical software groups to gather requirements, write and adopt a variety of design specifications, and develop demonstration projects to validate our approach. Numerical simulation is essential to the science mission at the laboratory. However, it is becoming increasingly difficult to manage the complexity of modern simulation software. Computational scientists develop complex, three-dimensional, massively parallel, full-physics simulations that require the integration of diverse software packages written by outside development teams. Currently, the integration of a new software package, such as a new linear solver library, can require several months of effort. Current industry component technologies such as CORBA, JavaBeans, and COM have all been used successfully in the business domain to reduce software development costs and increase software quality. However, these existing industry component infrastructures will not scale to support massively parallel applications in science and engineering. In particular, they do not address issues related to high-performance parallel computing on ASCI-class machines, such as fast in-process connections between components, language interoperability for scientific languages such as Fortran, parallel data redistribution between components, and massively

  12. Principal dynamical components

    CERN Document Server

    de la Iglesia, Manuel D

    2010-01-01

    A new procedure is proposed for the dimensional reduction of time series. Similarly to principal components, the procedure seeks a low-dimensional manifold that minimizes information loss. Unlike principal components, however, the new procedure involves dynamical considerations, through the proposal of a predictive dynamical model in the reduced manifold. Hence the minimization of the uncertainty is not only over the choice of a reduced manifold, as in principal components, but also over the parameters of the dynamical model. Further generalizations are provided to non-autonomous and non-Markovian scenarios, which are then applied to historical sea-surface temperature data.

  13. Explosive Components Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The 98,000 square foot Explosive Components Facility (ECF) is a state-of-the-art facility that provides a full-range of chemical, material, and performance analysis...

  14. Component maintenance system

    International Nuclear Information System (INIS)

    A component maintenance system having a network linked to a data acquisition system, a data analysis system, a historical file of component design and inspection information, and a diagnostic system having the capability to perform structural analysis of discontinuities identified by the data acquisition system. The network nodes may be located apart from each other, for example in the maintenance of a nuclear power plant steam generator, the data acquisition system may be located in a high radiation area while the data analysis system is safely located away from the radiation areas. Furthermore, the diagnostic system and the file of component design and inspection history information may be centrally located and sheared to support component evaluations being conducted in numerous geographic locations. Network communication facilitates the rapid evaluation of discontinuities, thereby permitting the inspection plan to be modified as the inspection results are obtained. (author) figs

  15. Space laser components reliability

    OpenAIRE

    Riede, Wolfgang; Schroeder, Helmut

    2015-01-01

    Space environment presents unique challenges for operation of optics and optical coatings as part of laser systems. Besides testing components and sub-systems on the component qualification level, the extended testing of complete laser systems like flight modules under acceptance level conditions is an effective way to determine the reliability and long term stability, mitigating the mission risk. Hence, optics as part of high power space laser systems have to be extensively tested in view...

  16. Stochastic component mode synthesis

    OpenAIRE

    Bah, Mamadou T.; Nair, Prasanth B.; Bhaskar, Atul; Keane, Andy J.

    2003-01-01

    In this paper, a stochastic component mode synthesis method is developed for the dynamic analysis of large-scale structures with parameter uncertainties. The main idea is to represent each component displacement using a subspace spanned by a set of stochastic basis vectors in the same fashion as in stochastic reduced basis methods [1, 2]. These vectors represent however stochastic modes in contrast to the deterministic modes used in conventional substructuring methods [3]. The Craig-Bampton r...

  17. Component fragility research program

    International Nuclear Information System (INIS)

    To demonstrate how ''high-level'' qualification test data can be used to estimate the ultimate seismic capacity of nuclear power plant equipment, we assessed in detail various electrical components tested by the Pacific Gas ampersand Electric Company for its Diablo Canyon plant. As part of our Phase I Component Fragility Research Program, we evaluated seismic fragility for five Diablo Canyon components: medium-voltage (4kV) switchgear; safeguard relay board; emergency light battery pack; potential transformer; and station battery and racks. This report discusses our Phase II fragility evaluation of a single Westinghouse Type W motor control center column, a fan cooler motor controller, and three local starters at the Diablo Canyon nuclear power plant. These components were seismically qualified by means of biaxial random motion tests on a shaker table, and the test response spectra formed the basis for the estimate of the seismic capacity of the components. The seismic capacity of each component is referenced to the zero period acceleration (ZPA) and, in our Phase II study only, to the average spectral acceleration (ASA) of the motion at its base. For the motor control center, the seismic capacity was compared to the capacity of a Westinghouse Five-Star MCC subjected to actual fragility tests by LLNL during the Phase I Component Fragility Research Program, and to generic capacities developed by the Brookhaven National Laboratory for motor control center. Except for the medium-voltage switchgear, all of the components considered in both our Phase I and Phase II evaluations were qualified in their standard commercial configurations or with only relatively minor modifications such as top bracing of cabinets. 8 refs., 67 figs., 7 tabs

  18. Refractory alloy component fabrication

    International Nuclear Information System (INIS)

    Purpose of this report is to describe joining procedures, primarily welding techniques, which were developed to construct reliable refractory alloy components and systems for advanced space power systems. Two systems, the Nb-1Zr Brayton Cycle Heat Receiver and the T-111 Alloy Potassium Boiler Development Program, are used to illustrate typical systems and components. Particular emphasis is given to specific problems which were eliminated during the development efforts. Finally, some thoughts on application of more recent joining technology are presented. 78 figures

  19. LMFBR fuel component costs

    International Nuclear Information System (INIS)

    A significant portion of the cost of fabricating LMFBR fuels is in the non-fuel components such as fuel pin cladding, fuel assembly ducts and end fittings. The contribution of these to fuel fabrication costs, based on FFTF experience and extrapolated to large LMFBR fuel loadings, is discussed. The extrapolation considers the expected effects of LMFBR development programs in progress on non-fuel component costs

  20. Different fixation methods for transverse acetabular fracture:a finite element analysis%有限元分析髋臼横行骨折不同植入物的内固定方式

    Institute of Scientific and Technical Information of China (English)

    周坚锋; 李建涛; 张浩; 李辰; 尹鹏; 李志锐; 陈宇翔; 唐佩福; 张立海

    2016-01-01

    BACKGROUND:Transverse acetabular fracture often involves the damage of anterior and posterior columns of acetabulum. The most popular fixation of the anterior and posterior columns needs the combined anterior and posterior approach. Big trauma is not conducive to patient’s recovery after surgery. Limited incision or percutaneous minimaly invasive lag screw placement can reduce soft tissue injuries, but the strength of the fixation lacks of biomechanical verification. OBJECTIVE: To compare different types of fixations for transverse acetabular fracture, explore the appropriate fixation options that can achieve effective fixation and reduce tissue injury by combing with repair approach and the condition of soft tissue. METHODS: The fourth generation of synthetic semi-pelvic sawbones was set as a template to establish a model of acetabular transverse fracture using finite element analysis. Five different fixation options were used to fix the transverse acetabular fracture. The magnitudes of anterior and posterior displacement of transverse fracture were compared to assess the stability of different options under a simulated condition of incomplete weight bearing stand. RESULTS AND CONCLUSION:The motion at anterior column was minimal when fixed by anterior column locking plate + posterior column screw and the minimum displacement at posterior column was the fixation of anterior column screw + posterior column locking plate. Both of the motions of these two fixations were less than the reconstruction plate fixation respectively. The worst fixation was the anterior column and posterior column lag screw fixation with the largest displacement. The anterior column locking plate + posterior column screw, accomplished by single approach, could not only reduce surgical trauma, but also has a stronger stability. Moreover, this fixation option is effective method to place posterior column lag screw under direct vision and reduce the difficulty of screw implantation.%背景:

  1. NASTRAN component-mode synthesis

    Science.gov (United States)

    Guyan, R. J.

    1976-01-01

    Procedure for dynamic substructuring analysis technique is generally as follows: calculation of component modes; selection of component normal modes, calculation of component generalized matrices, assembly of system matrices, and computation of normal modes; and retrieval of component response.

  2. Multiscale principal component analysis

    International Nuclear Information System (INIS)

    Principal component analysis (PCA) is an important tool in exploring data. The conventional approach to PCA leads to a solution which favours the structures with large variances. This is sensitive to outliers and could obfuscate interesting underlying structures. One of the equivalent definitions of PCA is that it seeks the subspaces that maximize the sum of squared pairwise distances between data projections. This definition opens up more flexibility in the analysis of principal components which is useful in enhancing PCA. In this paper we introduce scales into PCA by maximizing only the sum of pairwise distances between projections for pairs of datapoints with distances within a chosen interval of values [l,u]. The resulting principal component decompositions in Multiscale PCA depend on point (l,u) on the plane and for each point we define projectors onto principal components. Cluster analysis of these projectors reveals the structures in the data at various scales. Each structure is described by the eigenvectors at the medoid point of the cluster which represent the structure. We also use the distortion of projections as a criterion for choosing an appropriate scale especially for data with outliers. This method was tested on both artificial distribution of data and real data. For data with multiscale structures, the method was able to reveal the different structures of the data and also to reduce the effect of outliers in the principal component analysis

  3. Scientific Component Technology Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Kohn, S; Bosl, B; Dahlgren, T; Kumfert, G; Smith, S

    2003-02-07

    The laboratory has invested a significant amount of resources towards the development of high-performance scientific simulation software, including numerical libraries, visualization, steering, software frameworks, and physics packages. Unfortunately, because this software was not designed for interoperability and re-use, it is often difficult to share these sophisticated software packages among applications due to differences in implementation language, programming style, or calling interfaces. This LDRD Strategic Initiative investigated and developed software component technology for high-performance parallel scientific computing to address problems of complexity, re-use, and interoperability for laboratory software. Component technology is an extension of scripting and object-oriented software development techniques that specifically focuses on the needs of software interoperability. Component approaches based on CORBA, COM, and Java technologies are widely used in industry; however, they do not support massively parallel applications in science and engineering. Our research focused on the unique requirements of scientific computing on ASCI-class machines, such as fast in-process connections among components, language interoperability for scientific languages, and data distribution support for massively parallel SPMD components.

  4. Adaptable component frameworks

    DEFF Research Database (Denmark)

    Katajainen, Jyrki; Simonsen, Bo

    of balanced search tree. Also, we do provide safe and compact versions of each container. To ease the maintenance of this large collection of implementations, we have developed component frameworks for the STL containers. In this paper, we describe the design and implementation of a component...... framework for vector, which is undoubtedly the most used container of the C++ standard library. In particular, we specify the details of a vector implementation that is safe with respect to referential integrity and strong exception safety. Additionally, we report the experiences and lessons learnt from the...... development of component frameworks which we hope to be of benefit to persons engaged in the design and implementation of generic software libraries....

  5. An integrated magnetics component

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to an integrated magnetics component comprising a magnetically permeable core comprising a base member extending in a horizontal plane and first, second, third and fourth legs protruding substantially perpendicularly from the base member. First, second, third and...... fourth output inductor windings are wound around the first, second, third and fourth legs, respectively. A first input conductor of the integrated magnetics component has a first conductor axis and extends in-between the first, second, third and fourth legs to induce a first magnetic flux through a first...... flux path of the magnetically permeable core. A second input conductor of the integrated magnetics component has a second coil axis extending substantially perpendicularly to the first conductor axis to induce a second magnetic flux through a second flux path of the magnetically permeable core...

  6. Blood Component Therapy

    OpenAIRE

    Kelton, J. G.

    1984-01-01

    Human blood has been transfused for about 60-70 years. Over this time, the practice of blood transfusion has changed dramatically. One major change is the separation of blood into its various components. As a result, the patient can receive only the blood component in which he is deficient. In this way, the risk of side effects—particularly hepatitis—is lessened. This article briefly reviews the various blood products, the indications for their use, and some associated risks. These products i...

  7. Towards Cognitive Component Analysis

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Ahrendt, Peter; Larsen, Jan

    2005-01-01

    Cognitive component analysis (COCA) is here defined as the process of unsupervised grouping of data such that the ensuing group structure is well-aligned with that resulting from human cognitive activity. We have earlier demonstrated that independent components analysis is relevant for representing...... semantics, not only in text, but also in dynamic text (chat), images, and combinations of text and images. Here we further expand on the relevance of the ICA model for representing context, including two new analyzes of abstract data: social networks and musical features....

  8. Electronic components and systems

    CERN Document Server

    Dennis, W H

    2013-01-01

    Electronic Components and Systems focuses on the principles and processes in the field of electronics and the integrated circuit. Covered in the book are basic aspects and physical fundamentals; different types of materials involved in the field; and passive and active electronic components such as capacitors, inductors, diodes, and transistors. Also covered in the book are topics such as the fabrication of semiconductors and integrated circuits; analog circuitry; digital logic technology; and microprocessors. The monograph is recommended for beginning electrical engineers who would like to kn

  9. Cognitive Component Analysis

    DEFF Research Database (Denmark)

    Feng, Ling

    2008-01-01

    audio contexts along with pattern recognition methods to map components to known contexts. It also involves looking for the right representations for auditory inputs, i.e. the data analytic processing pipelines invoked by human brains. The main ideas refer to Cognitive Component Analysis, defined as the...... unsupervised learning discovers statistical regularities. However human cognition is too complicated and not yet fully understood. Nevertheless, in our approach we represent human cognitive processes as a classification rule in supervised learning. Thus we have devised a testable protocol to test the...

  10. Bayesian Independent Component Analysis

    DEFF Research Database (Denmark)

    Winther, Ole; Petersen, Kaare Brandt

    2007-01-01

    In this paper we present an empirical Bayesian framework for independent component analysis. The framework provides estimates of the sources, the mixing matrix and the noise parameters, and is flexible with respect to choice of source prior and the number of sources and sensors. Inside the engine...

  11. Component Reengineering Workshops

    DEFF Research Database (Denmark)

    Hansen, Klaus Marius; Christensen, Henrik Bærbak

    2004-01-01

    reengineering workshops, for assessing reengineering costs of reusing components between different product lines. The approach works on the level of software architectures, and relies critically on input from various (technical) stakeholders. It has been validated through case studies that are also presented...

  12. ITER plasma facing components

    International Nuclear Information System (INIS)

    This document summarizes results of the Conceptual Design Activities (1988-1990) for the International Thermonuclear Experimental Reactor (ITER) project, namely those that pertain to the plasma facing components of the reactor vessel, of which the main components are the first wall and the divertor plates. After an introduction and an executive summary, the principal functions of the plasma-facing components are delineated, i.e., (i) define the low-impurity region within which the plasma is produced, (ii) absorb the electromagnetic radiation and charged-particle flux from the plasma, and (iii) protect the blanket/shield components from the plasma. A list of critical design issues for the divertor plates and the first wall is given, followed by discussions of the divertor plate design (including the issues of material selection, erosion lifetime, design concepts, thermal and mechanical analysis, operating limits and overall lifetime, tritium inventory, baking and conditioning, safety analysis, manufacture and testing, and advanced divertor concepts) and the first wall design (armor material and design, erosion lifetime, overall design concepts, thermal and mechanical analysis, lifetime and operating limits, tritium inventory, baking and conditioning, safety analysis, manufacture and testing, an alternative first wall design, and the limiters used instead of the divertor plates during start-up). Refs, figs and tabs

  13. Validating Timed Component Contracts

    DEFF Research Database (Denmark)

    Le Guilly, Thibaut; Liu, Shaoying; Olsen, Petur;

    2015-01-01

    This paper presents a technique for testing software components with contracts that specify functional behavior, synchronization, as well as timing behavior. The approach combines elements from unit testing with model-based testing techniques for timed automata. The technique is implemented in an...... online testing tool, and we demonstrate its use on a concrete use case....

  14. Ubiquitous Fractal Components

    OpenAIRE

    Hoareau, Didier; Mahéo, Yves

    2006-01-01

    In this article we present a distribution scheme for Fractal-based applications that is namely based on a user-transparent extension to the Fractal component model. This scheme allows any Fractal application to expose it provided services in an ubiquitous way on several machines. The mechanisms implemented support network disconnections and let the application run in a degraded mode if necessary.

  15. Complement component 4

    Science.gov (United States)

    ... may have lower-than-normal levels of the complement proteins C3 and C4 . Complement activity varies throughout the body. ... Saunders; 2013:chap 6. Read More Cirrhosis Complement Complement component 3 (C3) Glomerulonephritis Hepatitis Hereditary angioedema Kidney transplant Lupus nephritis ...

  16. LABVirt – basic components

    Directory of Open Access Journals (Sweden)

    Codrin NISIOIU

    2006-01-01

    Full Text Available This article presents some aspects about a project integrated in a national research and development project "Information society" (INFOSOC financed by Romanian Government. A iLab called LABVirt is available for use by Universities, college, high-school.The goal of this paper is to present the main components of LABVirt, Romanian solution for remote lab access.

  17. One stage treatment of acetabular fractures combined with ipsilateral femoral head or neck fractures with total hip arthroplasty%Ⅰ期全髋置换术治疗合并股骨头或股骨颈骨折的髋臼骨折

    Institute of Scientific and Technical Information of China (English)

    唐孝明; 张耀明; 袁加斌; 庞健; 王跃

    2008-01-01

    目的 探讨全髋关节置换术(total hip arthroplasty,THA)治疗合并股骨头或股骨颈骨折的髋臼骨折方法、手术特点和疗效.方法 对7例合并股骨头或股骨颈骨折的髋臼骨折行Ⅰ期THA.髋臼骨折按AO分型:A型1例,B型3例,C型3例.股骨头骨折1例,股骨颈骨折6例.伤后7~21 d接受THA,5例行髋臼复位内固定后采用生物型髋臼,2例金属加强环配合骨水泥固定髋臼,股骨侧均采用生物型固定.结果 6例得到随访,平均随访时间3年9个月(2年3个月~6年5个月),出现脱位1例,经手法复位后未再脱位,1例出现异位骨化.所有随访患者髋关节功能均有明显改善,Harris评分术前平均48分,术后提高到91分.随访期内未发现假体松动.结论 THA是治疗合并同侧股骨头或股骨颈骨折髋臼骨折的有效方法,能显著改善关节功能,避免多次手术.%Objective To discuss method,operative characters and curative effect of total hip arthroplasty(THA)in treatment of acetabular fractures combined with ipsilateral femoral head or neck fractures.Methods One stage THA was done in seven patients with acetabular fractures combined with ipsilateral femoral head fracture(one patient)or femoral neck fractures(six patients)7-21 days after fractures.There were five males and two females,at age range of 41-65 years(average 50 years).According to AO classification,there were one patient with type A fracture,three with type B and three with type C.Of all,five patients received biological acetabular replacement after reduction and internal fixation of acetabular fracture and two received PMMA acetabular replacement with metal enforcement ring.All patients received biological femoral stem.Results Of all,six patients were followed up for from 2 years and 3 months to 6 years and 5 months(mean 3 years and 9 months),which showed heterotopic ossitlcation in one patient and dislocation in one who recovered after manipulative reduction.The Harris score was

  18. 三维记忆内固定与髋臼重建钛板系统修复髋臼后壁骨折伴关节后脱位的比较%Three-dimensional memory fixationversusreconstruction titanium plate to repair posterior wall acetabular fracture with posterior dislocation

    Institute of Scientific and Technical Information of China (English)

    梁云扬

    2015-01-01

    通过对髋臼三维记忆内固定系统在髋臼后壁骨折伴髋臼关节后脱位中临床应用效果的分析,了解其治疗髋臼后壁骨折伴髋臼关节后脱位的可行性与特点。研究发现,其在固定时间及术后功能恢复等方面较之重建钛板内固定都具有明显的应用优势。%BACKGROUND:Posterior wal fractures of the acetabulum with posterior dislocation of the acetabular joint mostly require the operation of open reduction and internal fixation. Different materials can be chosen for internal fixation operation. OBJECTIVE: To explore the effect of acetabular three-dimensional memory fixation system on acetabular posterior wal fractures accompanying the acetabulum joint dislocation. METHODS: A retrospective analysis was performed on clinical data of 92 cases of acetabular posterior wal fracture and dislocation at the Heze Municipal Hospital of Shandong Province from February 2010 to February 2014. Al patients received the operation of open reduction and internal fixation. They were divided into three-dimensional memory fixation group (45 cases) and reconstruction titanium plate group (47 cases) according to different fixators. Al patients were folowed up for 12 months after fixation. RESULTS AND CONCLUSION:The operation time and intraoperative blood loss were significantly longer or higher in the reconstruction titanium plate group than in the three-dimensional memory fixation group (P < 0.05). Harris score was significantly greater in the three-dimensional memory fixation group than in the reconstruction titanium plate group during final folow-up (P < 0.05). Thromboembolic complications or deep infection were not detected after fixation in both groups. These findings confirm that three-dimensional memory fixation system obtained good effects in the treatment of the posterior wal fractures of the acetabulum with posterior dislocation.

  19. Compressive Principal Component Pursuit

    CERN Document Server

    Wright, John; Min, Kerui; Ma, Yi

    2012-01-01

    We consider the problem of recovering a target matrix that is a superposition of low-rank and sparse components, from a small set of linear measurements. This problem arises in compressed sensing of structured high-dimensional signals such as videos and hyperspectral images, as well as in the analysis of transformation invariant low-rank recovery. We analyze the performance of the natural convex heuristic for solving this problem, under the assumption that measurements are chosen uniformly at random. We prove that this heuristic exactly recovers low-rank and sparse terms, provided the number of observations exceeds the number of intrinsic degrees of freedom of the component signals by a polylogarithmic factor. Our analysis introduces several ideas that may be of independent interest for the more general problem of compressed sensing and decomposing superpositions of multiple structured signals.

  20. Defining talent management components

    OpenAIRE

    Golchin Shafieian

    2014-01-01

    In today's world of global trade, it can guarantee success and excellence of organizations against competitors is talented human resources in an organization, especially at the managerial level. But the challenges that organizations face include: attracting, evaluating, exploring, and developing and keeping talent. The main objective of this study is to define the components of talent management in the University of Chaloos, in order to provide a way to reduce the challenges and short comings...

  1. Functional Components of Foods.

    OpenAIRE

    Guiné, Raquel; Lima, Maria João; Barroca, Maria João

    2010-01-01

    The primary role of diet is to provide sufficient nutrients to meet the nutritional requirements of an individual. However, many professionals recognise that health promoting foods have a major role in health enhancement, which justifies the focus on research on the identification of biologically active components in foods that have the potential to optimise physical and mental well being and which may also reduce the risk of disease. Recent increases on research also aimed the identification...

  2. Components of aging

    OpenAIRE

    Wiegand, Iris

    2013-01-01

    Age-related cognitive decline has been linked to a reduction in attentional resources that are assumed to result from alterations in the aging brain. A core ability that is subject to age-related decline is visual attention, which enables individuals to select the most important information for conscious processing and action. However, visual attention is considered a conglomerate of various functions and the specific components underlying age differences in performance remain little understo...

  3. Enterprise Architecture Evaluation Components

    OpenAIRE

    Niemi, Eetu; Ylimäki, Tanja

    2008-01-01

    Enterprise Architecture (EA) is a holistic view of an organization, including the viewpoints of business, information, systems and technology. It is stated to provide significant benefits to organizations, and is therefore of interest for both academics and practitioners. However, evaluating EA, or its benefits, is difficult. Moreover, the studies on EA evaluation are mostly inconsistent, and almost omit the planning aspect of evaluation. This study suggests the evaluation components that nee...

  4. Components of the environment

    International Nuclear Information System (INIS)

    This report of the Ministry of the Environment of the Slovak Republic deals with the components of the environment. The results of monitoring of air (emission situation), ambient air quality, atmospheric precipitation, tropospheric ozone, water (surface water, groundwater resources, waste water and drinking water), geological factors (geothermal energy, fuel deposits, ore deposits, non-metallic ore deposits), soil (area statistics, soil contamination. soil reaction and active extractable aluminium, soil erosion), flora and fauna (national strategy of biodiversity protection) are presented

  5. Components of QCD

    International Nuclear Information System (INIS)

    Some aspects of a simple strategy for testing the validity of QCD perturbation theory are examined. The importance of explicit evaluation of higher-order contributions is illustrated by considering Z0 decays. The recent progress toward understanding exclusive processes in QCD is discussed and some simple examples are given of how to isolate and test the separate components of the perturbation expansion in a hypothetical series of jet experiments

  6. Defining talent management components

    Directory of Open Access Journals (Sweden)

    Golchin Shafieian

    2014-07-01

    Full Text Available In today's world of global trade, it can guarantee success and excellence of organizations against competitors is talented human resources in an organization, especially at the managerial level. But the challenges that organizations face include: attracting, evaluating, exploring, and developing and keeping talent. The main objective of this study is to define the components of talent management in the University of Chaloos, in order to provide a way to reduce the challenges and short comings and also to look for ways to improve employee performance is discussed. This study is based on data collected from all employees of the University of Chaloos in August 2013; through two questionnaires have been developed. The statistical population has been considered 407 persons in these universities and according the Morgan Table, 198 persons were selected as sample of among research society. More over, 28 questions are used for determining components of talent management. Finally, we concluded that the component of talent management have been properly defined in the Universities of Chaloos.

  7. Analysis of the Effect of Artificial Hip Replacement in the Treatment of Acetabular Defect%髋臼缺损畸形的人工髋关节置换手术疗效分析

    Institute of Scientific and Technical Information of China (English)

    武豪杰

    2015-01-01

    Objective To study the acetabulum defect deformity treatment methods of artificial total hip replacement. Methods 30 cases of acetabular defects were selected in our hospital, including 13 cases of acetabulum hypoplasia, acetabulum fracture malunion after trauma in 5 cases, 6 patients with rheumatoid arthritis, ankylosing spondylitis hip lesions, 6 cases were performed total hip replacement, take the acetabulum deepening, double cone spiral acetabulum, autologous bone graft and structural methods such as titanium mesh and bone graft line true acetabular reconstruction, all patients preoperative CT three-dimensional reconstruction, with Harris scoring criteria. Results Followed up for 6~36 months, has not occurred during the follow-up period of artificial hip prosthesis loosening and fracture around, etc. Harris scoring (36±6.5) preoperatively, postoperative (93±5.2). Conclusion Deformity of total hip replacement for defects of acetabulum, through the acetabulum, Zweymulle double cone spiral acetabulum, grain pressure distribution, structural bone graft autologous bone graft and titanium mesh and bone graft and so on the many kinds of methods can be a very good reconstruction of acetabulum, restore good stability and the Harris score, can achieve very good effect.%目的探讨髋臼缺损畸形的人工全髋关节置换术的处理方法。方法选取我院收治存在髋臼缺损畸形患者30例,包括髋臼发育不良13例、髋臼创伤骨折后畸形愈合5例、类风湿性关节炎6例,强直性脊柱炎髋关节病变6例,均行全髋关节置换术,采取髋臼加深、双锥  面螺旋型髋臼、自体结构性植骨及钛网加植骨等多种方法行真臼重建,全部病例术前行 CT 三维重建,评分标准采用 Harris 评分。结果随访6~36个月,随访期间未发生人工髋关节假体松动、周围骨折等。Harris 评分术前(36±6.5),术后(93±5.2)。结论对于髋臼缺损畸形的全髋关节置

  8. 经髂腹股沟和Kocher-Langenbeck联合入路治疗复杂移位髋臼骨折%Treatment of complex acetabular fractures with combined ilio-inguinal and Kocher-Langenbeck approach

    Institute of Scientific and Technical Information of China (English)

    连鸿凯; 李兴华; 王爱国; 白玉

    2011-01-01

    Objective To investigate the clinical effect and treatment experience of complicated acetabular fractures treated with open reduction with combined ilio-inguinal and Kocher-Langenbeck (K-L) approaches.Methods Sixty-six patients with complicated acetabular fractures were treated surgically with combined ilio-inguinal and K-L approaches from February 2004 to December 2009.Among them,45 cases were followed up for 8-45 months,with the average 26 months.Results Operation time was 1.4-5.7 h,with the average of 2.8 h.Intraoperative blood loss was 530-2300 ml,with the average of 1250 ml.According to Matta's score system,the excellent and good rate was 86.7%.According to modified Merle d' Aubigne and Postel score system,the excellent and good rate of function of hip was 86.7%.According to Brooker heterotopic ossification standard assessment system:Ⅰ degrees in 6,Ⅱ degrees in 3.According to Letournel and Judet clinical classification system,postoperative traumatic arthritis were 6 patients.Among them,3 patients with Ⅲ- Ⅴ period with symptoms of serious hip pain and joint activities obstacles were treated with total hip replacement secondly.Six cases of sciatic nerve injury and 9 cases of lateral femoral cutaneous nerve damage were recovered gradually after six months to a year.All incisions healed primarily.All got bony union,the healing time was 8 to 16 weeks,with the average of 10.4 weeks.None was complicated with femoral head necrosis.Conclusion For the patients with complicated acetabular fractures,open reduction with combined ilio-inguinal and K-L approaches can get clinical advantages of revealed fully,fracture restoration convenient,fixed tightly,fewer complications and satisfactory result.%目的 探讨采用经髂腹股沟和Kocher-Langenbeck(K-L)联合入路行切开复位内固定治疗复杂移位髋臼骨折的疗效.方法2004年2月至2009年12月,采用经髂腹股沟和K-L联合入路治疗66例复杂移位髋臼骨折,对其中获得随访的45

  9. Electronic components and technology

    CERN Document Server

    Sangwine, Stephen

    2007-01-01

    Most introductory textbooks in electronics focus on the theory while leaving the practical aspects to be covered in laboratory courses. However, the sooner such matters are introduced, the better able students will be to include such important concerns as parasitic effects and reliability at the very earliest stages of design. This philosophy has kept Electronic Components and Technology thriving for two decades, and this completely updated third edition continues the approach with a more international outlook.Not only does this textbook introduce the properties, behavior, fabrication, and use

  10. Making Components Fit: SPINing

    Czech Academy of Sciences Publication Activity Database

    Kofroň, Jan; Poch, T.; Šerý, O.

    Los Alamitos : IEEE Computer Society, 2009, s. 65-74. ISBN 978-0-7695-3617-0. [SEW 2008. Annual IEEE/NASA Software Engineering Workshop /32./. Kassandra (GR), 15.10.2008-16.10.2008] R&D Projects: GA ČR(CZ) GD201/05/H014 Grant ostatní: GA ČR(CZ) GA201/06/0770 Institutional research plan: CEZ:AV0Z10300504 Keywords : software components * behavior specification * model-checking Subject RIV: JC - Computer Hardware ; Software

  11. Autonomous component carrier selection

    DEFF Research Database (Denmark)

    Garcia, Luis Guilherme Uzeda; Pedersen, Klaus; Mogensen, Preben

    2009-01-01

    in local areas, basing our study case on LTE-Advanced. We present extensive network simulation results to demonstrate that a simple and robust interference management scheme, called autonomous component carrier selection allows each cell to select the most attractive frequency configuration; improving...... management and efficient system operation. Due to the expected large number of user-deployed cells, centralized network planning becomes unpractical and new scalable alternatives must be sought. In this article, we propose a fully distributed and scalable solution to the interference management problem...

  12. Advanced Power Electronics Components

    Science.gov (United States)

    Schwarze, Gene E.

    2004-01-01

    This paper will give a description and status of the Advanced Power Electronics Materials and Components Technology program being conducted by the NASA Glenn Research Center for future aerospace power applications. The focus of this research program is on the following: 1) New and/or significantly improved dielectric materials for the development of power capacitors with increased volumetric efficiency, energy density, and operating temperature. Materials being investigated include nanocrystalline and composite ceramic dielectrics and diamond-like carbon films; 2) New and/or significantly improved high frequency, high temperature, low loss soft magnetic materials for the development of transformers/inductors with increased power/energy density, electrical efficiency, and operating temperature. Materials being investigated include nanocrystalline and nanocomposite soft magnetic materials; 3) Packaged high temperature, high power density, high voltage, and low loss SiC diodes and switches. Development of high quality 4H- and 6H- SiC atomically smooth substrates to significantly improve device performance is a major emphasis of the SiC materials program; 4) Demonstration of high temperature (> 200 C) circuits using the components developed above.

  13. Interactions between photodegradation components

    Directory of Open Access Journals (Sweden)

    Abdollahi Yadollah

    2012-09-01

    Full Text Available Abstract Background The interactions of p-cresol photocatalytic degradation components were studied by response surface methodology. The study was designed by central composite design using the irradiation time, pH, the amount of photocatalyst and the p-cresol concentration as variables. The design was performed to obtain photodegradation % as actual responses. The actual responses were fitted with linear, two factor interactions, cubic and quadratic model to select an appropriate model. The selected model was validated by analysis of variance which provided evidences such as high F-value (845.09, very low P-value (2 = 0.999, adjusted R-squared (Radj2 = 0.998, predicted R-squared (Rpred2 = 0.994 and the adequate precision (95.94. Results From the validated model demonstrated that the component had interaction with irradiation time under 180 min of the time while the interaction with pH was above pH 9. Moreover, photocatalyst and p-cresol had interaction at minimal amount of photocatalyst (p-cresol. Conclusion These variables are interdependent and should be simultaneously considered during the photodegradation process, which is one of the advantages of the response surface methodology over the traditional laboratory method.

  14. Laser generating metallic components

    Science.gov (United States)

    McLean, Marc A.; Shannon, G. J.; Steen, William M.

    1997-04-01

    Recent developments in rapid prototyping have led to the concept of laser generating, the first additive manufacturing technology. This paper presents an innovative process of depositing multi-layer tracks, by fusing successive powder tracks, to generate three dimensional components, thereby offering an alternative to casting for small metal component manufacture. A coaxial nozzle assembly has been designed and manufactured enabling consistent omni-directional multi-layer deposition. In conjunction with this the software route from a CAD drawing to machine code generation has been established. The part is manufactured on a six axes machining center incorporating a 1.8 kW carbon-dioxide laser, providing an integrated opto-mechanical workstation. The part build-up program is controlled by a P150 host computer, linked directly to the DNC machining center. The direct manufacturing route is shown, including initial examples of simple objects (primitives -- cube, cylinder, cone) leading to more complex turbine blade generation, incorporating build-up techniques and the associated mechanical properties.

  15. Follow up of biocompatibity of new total hip joint endoprosthesis in a canine model

    Directory of Open Access Journals (Sweden)

    Ľ. Rehák

    2010-11-01

    Full Text Available Purpose: of this paper was the follow up of biologic compatibility and functional use of new type endoprosthesis in a canine model.Design/methodology/approach: Prospective animal study with evaluation of new type ZRM of titanium alloy cementless total hip replacement (THR in dogs in 2007. We used congruent ceramic head and polyethylene acetabular inlay. That is the gold standard in THR. The methods of X ray imaging evaluation after implantation and overgrowth evaluation were employed. We evaluated loading and use of the leg during walking and running. Total hip joint replacements were implanted in 6 dogs – German Shepards under general anesthesia. The follow up time was 6 months. We compared X ray findings after the operation and after 6 months, wound healing, use of THR during leg loading and biocompatibility of THR in femur and pelvis.Findings: The femoral and acetabular components were anchored using a press-fit technique. We found good biocompatibility in 5 dogs with good loading during walking and running, one complication with femoral fracture and wound abscess. At six months, there was good bony ongrowth of the THR in 5 dogs and small overgrowth on the surface of THR in one dog, deemed as complication. In the same animal, explanation of the THR was performed, due to fracture.Research limitations/implications: This study was not monitored. In the future, we would like to perform a randomized study design with a control group.Practical implications: The new THR developed by authors can restore function in canine model of damaged hip joint. The press fit anchorage of the cup allowed firm adhesion of the cup surface to the pelvic bone and likewise, the femoral component demonstrated firm fixation in the proximal femur.Originality/value: This paper is original by presenting the first results of new THR in canine model. The value of this paper is in laying groundwork for human study in the future.

  16. 髋臼双柱骨折四种固定方式的生物力学比较及临床意义%Biomechanical study of four kinds of internal fixation techniques in the treatment of acetabular both-column fractures

    Institute of Scientific and Technical Information of China (English)

    朱李梅; 李明; 徐爱君; 张经纬; 何贤峰; 王虎

    2015-01-01

    目的 比较髋臼双柱骨折4种内固定方法在不同载荷下的生物力学特点.方法 利用CT图像,建立左侧髋臼双柱骨折三维有限元模型.比较四边区十字钢板、后路双重建钢板、髋臼三柱空心螺钉、新型解剖钢板固定,模拟上半身重量约60 kg坐位、向左转身、向右转身时的受力,施加600N的垂直载荷,向左旋转及向右旋转方向分别施加8 N/M的扭矩,时长1 s,Von Mises应力公式分析内固定的受力.结果 (1)垂直载荷及向左旋转工况下,应力峰值为:解剖板>十字板>后路双板>三柱钉,向右旋转工况为:十字板>解剖板>后路双板>三柱钉.(2)坐位向右转身,四边区十字板位于髂窝臼顶区域的位移最大,耻骨结节处的螺钉应力最大.(3)坐位向左转身,臼顶区域的后路双板内侧钢板近端应力及位移最大,臼顶内上方区域的髋臼后柱螺钉应力最大,髂后上嵴区域的横向双柱钉位移最大.位移峰值为:十字板>解剖板>后路双板>三柱钉.结论 三柱钉固定最稳定,解剖板应力分布较均匀,稳定性与后路双重建钢板相似.钢板固定时,应避免与拧人螺钉反方向的转身动作,减少内植物变形、松动滑脱、断裂、复位丢失等并发症.%Objective To compare the biomechanical properties of four kinds of internal fixation techniques for acetabular both columns fractures.Methods A three-dimensional finite element model of left acetabular both-column fracture was established according to pelvic computed tomography (CT) images and photo software.Four kinds of internal fixation techniques,including quadrilateral double plates,posterior double reconstruction plates,acetabular three-column canulated screws,new anatomical plate were performed separately by the three-dimensional finite element model.These four models were put into Abaqus finite element program,axial load 600 N on vertical compression,and 8 N/M (1 S) torque were loaded on left

  17. Component failure data handbook

    Energy Technology Data Exchange (ETDEWEB)

    Gentillon, C.D.

    1991-04-01

    This report presents generic component failure rates that are used in reliability and risk studies of commercial nuclear power plants. The rates are computed using plant-specific data from published probabilistic risk assessments supplemented by selected other sources. Each data source is described. For rates with four or more separate estimates among the sources, plots show the data that are combined. The method for combining data from different sources is presented. The resulting aggregated rates are listed with upper bounds that reflect the variability observed in each rate across the nuclear power plant industry. Thus, the rates are generic. Both per hour and per demand rates are included. They may be used for screening in risk assessments or for forming distributions to be updated with plant-specific data.

  18. Hyaluronan: A Matrix Component

    Science.gov (United States)

    Rügheimer, Louise

    2008-09-01

    The glucosaminoglycan hyaluronan is a key component of the extracellular matrix. It is a large, negatively charged molecule that can act as an ion exchange reservoir for positive ions. Hyaluronan is involved in renomedullary water handling through its water-binding capacity. In the renal medulla, the main source for hyaluronan production is the renomedullary interstitial cells. Hyaluronan synthases are found in the inner part of the plasma membrane and polymerize hyaluronan chains which are extruded into the extracellular space. Hyaluronidases are a family of enzymes involved in the degradation of hyaluronan. They have a wide range of properties, including differences in size, inhibitor sensitivities, catalytic mechanisms, substrate specificities and pH optima.

  19. Impedance and component heating

    CERN Document Server

    Métral, E; Mounet, N; Pieloni, T; Salvant, B

    2015-01-01

    The impedance is a complex function of frequency, which represents, for the plane under consideration (longitudinal, horizontal or vertical), the force integrated over the length of an element, from a “source” to a “test” wave, normalized by their charges. In general, the impedance in a given plane is a nonlinear function of the test and source transverse coordinates, but it is most of the time sufficient to consider only the first few linear terms. Impedances can influence the motion of trailing particles, in the longitudinal and in one or both transverse directions, leading to energy loss, beam instabilities, or producing undesirable secondary effects such as excessive heating of sensitive components at or near the chamber wall, called beam-induced RF heating. The LHC performance limitations linked to impedances encountered during the 2010-2012 run are reviewed and the currently expected situation during the HL-LHC era is discussed.

  20. Food Components and Supplements

    DEFF Research Database (Denmark)

    Parlesak, Alexandr

    2012-01-01

    The major part of food consists of chemical compounds that can be used for energy production, biological synthesis, or maintenance of metabolic processes by the host. These components are defined as nutrients, and can be categorized into macronutrients (proteins, carbohydrates, triglycerides, and...... alcohol), minerals, and micronutrients. The latter category comprises 13 vitamins and a hand full of trace elements. Many micronutrients are used as food supplements and are ingested at doses exceeding the amounts that can be consumed along with food by a factor of 10–100. Both macro- and micronutrients...... supplements and contaminants can compete directly with drug oxidation, induce or suppress the expression of xenobiotic-metabolizing enzymes, change the bioavailability of drugs, and, in the case of live bacteria, bring in their own xenobiotic metabolism, including cytochrome P450 (CYP) activity. In numerous...

  1. Solar bowl component efficiencies

    Energy Technology Data Exchange (ETDEWEB)

    O' Hair, E.A.; Green, B.L. (College of Engineering, Texas Tech. Univ., Lubbock, TX (United States))

    1992-11-01

    Battelle Pacific Northwest Laboratory has published two volumes on the economic evaluation of various proposed configurations and plant sizes for the four solar thermal technologies. These are the latest in a series of publications sponsored by the Department of Energy (DOE) on plant and operational costs and are more complete in that they include calculations of electrical output. These latest Battelle volumes use the 1976 solar data from Barstow, Calif., and by calculating or estimating the energy conversion efficiency of each element in the process from sun to electricity predict the output and cost of electricity from different plant sizes for each of the four technologies. In this paper a comparison is presented of the component efficiencies developed by Battelle and those of the solar bowl at Crosbyton, Tex.

  2. The mechanical components market

    International Nuclear Information System (INIS)

    Evolution of CANDU power station design is described and installed nuclear power in Canada to 2000 is forecast. The predicted value of various mechanical components is depicted. Improvements are being made in reliability and speed of repair, which reduce man-rem expenditure in concert with radiation field reduction. Actual reactor operating performance is very good; a significant portion of power plant downtime is associated with steam turbine and generator unreliability. Heavy water upkeep has been reduced by improved equipment layout, live loading of valve stem packing, improved flange seals, and improved leak detection techniques. Steam generator tube reliability is 1000 times better than that of light water reactors. Pump seal reliability has progressed to the point that current station design eliminates pump redundancy. Fuel bundle defect rates are now less than 0.03%. (E.C.B.)

  3. Optical communication components

    Science.gov (United States)

    Eldada, Louay

    2004-03-01

    We review and contrast key technologies developed to address the optical components market for communication applications. We first review the component requirements from a network perspective. We then look at different material systems, compare their properties, and describe the functions achieved to date in each of them. The material systems reviewed include silica fiber, silica on silicon, silicon on insulator, silicon oxynitride, sol-gels, polymers, thin-film dielectrics, lithium niobate, indium phosphide, gallium arsenide, magneto-optic materials, and birefringent crystals. We then describe the most commonly used classes of optical device technology and present their pros and cons as well as the functions achieved to date in each of them. The technologies reviewed include passive, actuation, and active technologies. The passive technologies described include fused fibers, dispersion-compensating fiber, beam steering, Bragg gratings, diffraction gratings, holographic elements, thin-film filters, photonic crystals, microrings, and birefringent elements. The actuation technologies include thermo-optics, electro-optics, acousto-optics, magneto-optics, electroabsorption, liquid crystals, total internal reflection technologies, and mechanical actuation. The active technologies include heterostructures, quantum wells, rare-earth doping, dye doping, Raman amplification, and semiconductor amplification. We also investigate the use of different material systems and device technologies to achieve building-block functions, including lasers, amplifiers, detectors, modulators, polarization controllers, couplers, filters, switches, attenuators, isolators, circulators, wavelength converters, chromatic dispersion compensators, and polarization mode dispersion compensators. Some of the technologies presented are well established in the industry and in some cases have reached the commodity stage, others have recently become ready for commercial introduction, while some others

  4. Distributed and Parallel Component Library

    Institute of Scientific and Technical Information of China (English)

    XU Zheng-quan; XU Yang; YAN Ai-ping

    2005-01-01

    Software component library is the essential part of reuse-based software development. It is shown that making use of a single component library to store all kinds of components and from which components are searched is very inefficient. We construct multi-libraries to support software reuse and use PVM as development environments to imitate largescale computer, which is expected to fulfill distributed storage and parallel search of components efficiently and improve software reuse.

  5. 3D visualization of the Letournel-Judet clssification of acetabular fractures based on a desktop virtual reality%基于桌面虚拟现实技术实现髋臼骨折Letournel-Judet分类的三维浏览

    Institute of Scientific and Technical Information of China (English)

    苏秀云; 刘蜀彬; 裴国献

    2011-01-01

    目的 介绍使用HTML和虚拟现实建模语言(VRML)建立通过Web远程访问的髋臼骨折Letournel-Judet分类三维数字化浏览. 方法 首先,根据髋臼骨折Letounel-Judet分型,将重建的1例女性志愿者髋部骨骼模型通过Mimics软件的仿真模块切割模拟每一种骨折类型,将每一种骨折类型的骨折块以虚拟现实建模语言的格式.wrl导出.其次,编辑html网页,为每个骨折块建一个主菜单,每个主菜单设立调整透明度(透明、恢复、隐藏和显示)的子菜单.最后,编辑VRML文件,基于JavaScript语言建立 HTML与 VRML的通迅,实现各种骨折类型骨折块不同透明度的任意组合显示.结果 建立了髋臼骨折Letournel-Judet三维数字化分类系统(它分为5个部分),可以方便的通过远程网络访问.结论 该方法可以方便地应用于临床,提供对髋臼骨折的诊断与分析功能,使临床医生在极短的时间内可以对各类骨折的发生状况做出正确诊断.%Objective To establish a 3D atlas of Letournel-Judet classifications of acetabular fractures which provides remote access on the web through hypertext markup language (HTML) and virtual reality modeling language (VRML) for efficient remote diagnosis. Methods Firstly,different Letournel-Judet classifications of acetabular fracture were simulated based on 3D reconstruction models of healthy volunteers via Mimics software.The files of VRML format were exported after geometry modeling.Secondly,The.wrl files were edited by adding nodes of Sensor,Route,and Script to the files to make the static scene respond to users' interaction.Finally,the homepage of 3D atlas was established with the Dreamweaver software.Results The 3D atlas of Letournel-Judet classifications of acetabular fractures was established which can be accessed online.These virtual worlds can be browsed via the Internet and hyperlinked with the World Wide Web. Conclusion The 3D atlas of Letournel-Judet classifications of

  6. Surface Active Components: Review

    Directory of Open Access Journals (Sweden)

    Z. Shafiei

    2014-03-01

    Full Text Available Biosurfactant or surface active components are produced by many different microorganisms. Biosurfactants are amphiphilic molecules with both hydrophilic and hydrophobic (generally hydrocarbon moieties that partition preferentially a within the interface between fluid phases with some other degrees of polarity and hydrogen bonding including oil/water or air/water interfaces. These properties render surfactants able to reducing surface and interfacial tension and forming microemulsion where hydrocarbons can solubilize in water or where water can solubilize in hydrocarbons, the majority of surfactants have gained importance in the fields of enhanced oil recovery, environmental bioremediation, food processing and pharmaceuticals. However, large-scale production of these molecules has not been realized as a result of low yields in production processes and high recovery and purification costs. This review article represents a classification of biosurfactant in addition to their microbial origin and effect of some nutrition and environmental factor for high production of biosurfactant. The nitrogen, carbon sources and environmental factors can make a difference key to the regulating biosurfactants synthesis Fascination with microbial surfactants have been steadily increasing recently because of advantages over the chemical surfactants for example environmentally friendly nature, lower toxicity, higher biodegradability, higher selectivity and specific gravity at extreme temperature, pH and salinity. For this reason the demand of biosurfactant are increasing day by day.

  7. RTD Component 6

    International Nuclear Information System (INIS)

    Within the Integrated Project FUNMIG RTD Component 6 plays the role of the coordinator for linking the scientific work with the application of its results in Performance Assessment. The linking itself is in the custody of RTDCs 1-5. To play its role as coordinator an information exchange forum was furnished: On one hand all the Waste Management Organisations (WMOs) involved in FUNMIG participate in RTDC 6; on the other hand an Integration Monitoring Group (IMG) representing RTDCs 1-5 was established. RTDC 6 is divided into three work packages (WPs): WP 6.1 deals with the boundary conditions to the near field and will consider the outcome of NF-PRO, a sister project within the sixth Framework Programme. WP 6.2 is the core task of RDTC 6. It monitors the scientific results of the project with respect to their application in PA and will give feedback to researchers. Within WP 6.3 Sorption data bases currently used by participating WMOs were compiled and a frame to compile sorption data acquired within FUNMIG will be established

  8. Towards Prognostics for Electronics Components

    Data.gov (United States)

    National Aeronautics and Space Administration — Electronics components have an increasingly critical role in avionics systems and in the development of future aircraft systems. Prognostics of such components is...

  9. Cooling system for electronic components

    Energy Technology Data Exchange (ETDEWEB)

    Anderl, William James; Colgan, Evan George; Gerken, James Dorance; Marroquin, Christopher Michael; Tian, Shurong

    2016-05-17

    Embodiments of the present invention provide for non interruptive fluid cooling of an electronic enclosure. One or more electronic component packages may be removable from a circuit card having a fluid flow system. When installed, the electronic component packages are coincident to and in a thermal relationship with the fluid flow system. If a particular electronic component package becomes non-functional, it may be removed from the electronic enclosure without affecting either the fluid flow system or other neighboring electronic component packages.

  10. Multilevel Contracts for Trusted Components

    Directory of Open Access Journals (Sweden)

    Mohamed Messabihi

    2010-10-01

    Full Text Available This article contributes to the design and the verification of trusted components and services. The contracts are declined at several levels to cover then different facets, such as component consistency, compatibility or correctness. The article introduces multilevel contracts and a design+verification process for handling and analysing these contracts in component models. The approach is implemented with the COSTO platform that supports the Kmelia component model. A case study illustrates the overall approach.

  11. Cooling system for electronic components

    Science.gov (United States)

    Anderl, William James; Colgan, Evan George; Gerken, James Dorance; Marroquin, Christopher Michael; Tian, Shurong

    2015-12-15

    Embodiments of the present invention provide for non interruptive fluid cooling of an electronic enclosure. One or more electronic component packages may be removable from a circuit card having a fluid flow system. When installed, the electronic component packages are coincident to and in a thermal relationship with the fluid flow system. If a particular electronic component package becomes non-functional, it may be removed from the electronic enclosure without affecting either the fluid flow system or other neighboring electronic component packages.

  12. Formalization in Component Based Development

    DEFF Research Database (Denmark)

    Holmegaard, Jens Peter; Knudsen, John; Makowski, Piotr;

    2006-01-01

    We present a unifying conceptual framework for components, component interfaces, contracts and composition of components by focusing on the collection of properties or qualities that they must share. A specific property, such as signature, functionality behaviour or timing is an aspect. Each aspe...

  13. 改良髂腹股沟入路髋臼周围截骨术治疗髋臼发育不良%A Modified Ilioinguinal Approach to Bernese Periacetabular Osteotomy for Congenital Acetabular Dysplasia

    Institute of Scientific and Technical Information of China (English)

    周新华; 吕明; 吴坚; 唐杞衡; 王敏

    2014-01-01

    目的:研究改良髂腹股沟入路在行伯尔尼髋臼周围截骨术(Bernese periacetabular osteotomy )治疗髋臼发育不良的可行性。方法自2008年5月~2012年6月,采用改良的髂腹股沟入路行伯尔尼髋臼周围截骨术治疗15例(共17髋)因髋臼发育不良造成髋关节疼痛的患者。患者平均年龄35.6岁(16~48岁),男1例1髋,女14例16髋。测量术前、术后髋臼的CE角和AC角,记录骨关节炎的严重程度并进行随访,对髋关节进行 Harris评分。结果所有患者髋臼周围截骨术后股骨头覆盖均得到改善,CE角由术前(4.50°±4.18°)矫正为(28.80°±6.71°),AC角由术前的(26.54°±5.73°)矫正为(4.20°±5.22°)。平均随访3.5年(1~5年),17髋疼痛均减轻,骨关节炎得到一定控制,Harris评分由术前(81.21±5.45)分改善为(96.82±6.76)分,无截骨块不愈合及重要神经损伤病例。结论改良的髂腹股沟入路行伯尔尼髋臼周围截骨术治疗成人髋臼发育不良可以获得较好疗效,是一种有效、安全的手术方式。%Objective To examine the feasibility of a modified ilioinguinal approach to Bernese periacetabular osteotomy for congenital acetabular dysplasia.Methods From May 2008 to June 2012 ,15 patients (17 hips) with an average age of 35.6 years (range:16 to 48 years ,1 male and 16 females) were treated with Bernese periacetabular osteotomy with a modified ilioinguinal approach.The CE angle and AC angle were evaluated radiographically before and after the operation.Hips were evaluated with the use of osteoarthritis index and Harris score postoperatively.Results The coverage of the femoral head was enhanced after surgery in all patients.Significant improvement was seen radiographically with regard to the CE angle which changed from (4.50°±4.18°)to(28.80°±6.71°),andACanglewhichchangedfrom(26.54°±5.73°)to(4.20°±5.22

  14. 经改良Smith-Peterson入路行Bernese髋臼周围截骨治疗成人髋臼发育不良%A modified smith-peterson approach to bernese periacetabular osteotomy for congenital acetabular dysplasia

    Institute of Scientific and Technical Information of China (English)

    倪喆; 尚希福; 吴科荣; 胡飞

    2015-01-01

    Objective To examine the feasibility of a modified Smith-Peterson approach to the Bernese periacetabular osteotomy for Congenital Acetabular Dysplasia of adults and analyze the short-term clinical effect.Methods Totally 21 patients with 23 hips underwent the Bernese periacetabular osteotomy with a modified Smith-Peterson approach from July 2011 to June 2013 were adopted in this study. They included 5 males (5 hips) and 16 females (18 hips), aged 18 to 48 years old with a mean of 32.7. The blood loss and operation duration were recorded. The CE angle and Tonnis angle were evaluated radiographically pre-and post-operation, as well as progressed Harris Score.Results The coverage of the femoral head was enhanced post-operation in all patients. The time of the operation was (93±21) min and the bleeding volume was (550±135)ml. Significant improvement was seen radiographically with regard to the lateral CE angle which changed from 7.52°±4.67° to 30.26°±2.65°, anterior CE angle from 9.39°±3.04° to 25.52°±3.44°, and Tonnis angle from 22.36°± 6.79° to 7.28°±4.08°. All patients were followed-up in one year post-operation, Harris score was improved from 75.45±6.28 to 95.93±3.19. No nonunion of bone osteotomy and nerve injury were founded.Conclusion The modified Smith-Peterson approach to Bernese periacetabular osteotomy for congenital acetabular dysplasia is effective and safe. The outcomes is satisfy.%目的 研究改良Smith-Peterson入路在伯尔尼截骨治疗成人髋臼发育不良的可行性,并探讨其短期临床疗效.方法 自2011年7月到2013年6月,采用改良Smith-Peterson入路行Bernese髋臼截骨共治疗髋臼发育不良患者共21例23髋.其中男5例5髋,女16例18髋;年龄18~48岁,平均32.7岁.记录手术时间及术中出血量,测量术前、术后髋臼的CE角和Tonnis角,并对髋关节功能行Harris评分.结果 所有患者髋臼周围截骨术后股骨头覆盖均得到改善,手术时间为(93±21)min

  15. Efficacy observation of acetabular cups of hip replacement surgery on adult hip crowe II and III dysplasia%大臼杯全髋关节置换术治疗 CroweⅡ~Ⅲ型成人髋关节发育不良疗效观察

    Institute of Scientific and Technical Information of China (English)

    谢贵杰; 何森荣; 甘伟伟

    2014-01-01

    目的:总结大型臼杯生物型人工全髋关节置换术治疗CroweⅡ~Ⅲ型成人髋关节发育的早期疗效。方法12例12髋, CroweⅡ型为7例,CroweⅢ型为5例,全髋关节置换术臼杯外径58~64 mm,假体选用国产爱康宜诚公司生产的假体。结果随访2~3年。髋关节功能Harris标准评分平均92分,其中功能优9例,良3例,目前尚无1例需行翻修。结论对部分CroweⅡ、Ⅲ型成人髋关节发育不良,采用大型臼杯全髋关节置换术治疗早期能够获得满意的临床疗效。%Objective To summize the early efficacy of large-scare acetabular cups of hip replacement surgery on adult hip Crowe II and III dysplasia .Methods There were 12 patients in which 7 cases were Crowe II and 5 cases were Crowe III .The outside diameter of acetabular cup for total hip replacement surgery was 58~64 mm.Ai-Kang prostheses which were made in China were used .Results The patients were followed up for 2 to 3 years.The average Harris hip standard score was 92.The hip functions of 9 cases were excel-lent and those of 3 cases were good .No case needed to restore .Conclusions For some cases of adult hip Crowe II and III dysplasia , early hip replacement surgery with large-scare acetabular cups can obtain satisfactory clinical effect .

  16. Component-specific modeling. [jet engine hot section components

    Science.gov (United States)

    Mcknight, R. L.; Maffeo, R. J.; Tipton, M. T.; Weber, G.

    1992-01-01

    Accomplishments are described for a 3 year program to develop methodology for component-specific modeling of aircraft hot section components (turbine blades, turbine vanes, and burner liners). These accomplishments include: (1) engine thermodynamic and mission models, (2) geometry model generators, (3) remeshing, (4) specialty three-dimensional inelastic structural analysis, (5) computationally efficient solvers, (6) adaptive solution strategies, (7) engine performance parameters/component response variables decomposition and synthesis, (8) integrated software architecture and development, and (9) validation cases for software developed.

  17. Failure analysis of sandwich-type ceramic-on-ceramic hip joints: A spectroscopic investigation into the role of the polyethylene shell component.

    Science.gov (United States)

    Okita, Shinya; Hasegawa, Masahiro; Takahashi, Yasuhito; Puppulin, Leonardo; Sudo, Akihiro; Pezzotti, Giuseppe

    2014-03-01

    The mechanisms leading to systematic failure in modular acetabular components with a sandwich insertion (alumina/polyethylene/titanium) have been reconsidered in light of the newly collected Raman spectroscopic results. Raman assessments were conducted on the polyethylene shells, which belonged to a series of six failed sandwich implants with in vivo lifetimes ranging between 2 and 9yr. With only one exception, all implants commonly showed dislodgment of the polyethylene shell during radiographic analyses prior to revision surgery. The polyethylene shell slipped out of the backing titanium shell, while always remaining integer to the ceramic liner. Four implants fractured at the ceramic liners, but their fractures occurred according to distinctly different patterns, which could be rationalized and classified. The insertion of the polyethylene layer, originally conceived to reduce the rigidity of the ceramic-on-ceramic bearing and to prevent impingement between the ceramic liner rim and the femoral neck, played a role in implant failure with its initial (asymmetric) thickness reduction due to creep deformation (eventually followed by cup rotation and backside wear). The results of the present spectroscopic investigation suggest that a simplistic failure classification of the sandwich-type implant as a "ceramic fracture failure" could be misleading and might represent a confounding factor in judging about the reliability of modern ceramic implants. PMID:23466283

  18. Multi-component assembly casting

    Energy Technology Data Exchange (ETDEWEB)

    James, Allister W.

    2015-10-13

    Multi-component vane segment and method for forming the same. Assembly includes: positioning a pre-formed airfoil component (12) and a preformed shroud heat resistant material (18) in a mold, wherein the airfoil component (12) and the shroud heat resistant material (18) each comprises an interlocking feature (24); preheating the mold; introducing molten structural material (46) into the mold; and solidifying the molten structural material such that it interlocks the pre-formed airfoil component (12) with respect to the preformed shroud heat resistant material (18) and is effective to provide structural support for the shroud heat resistant material (18). Surfaces between the airfoil component (12) and the structural material (46), between the airfoil component (12) and the shroud heat resistant material (18), and between the shroud heat resistant material (18) and the structural material (46) are free of metallurgical bonds.

  19. Frameworks Between Components And Objects

    Directory of Open Access Journals (Sweden)

    Mohamed Belal

    2012-10-01

    Full Text Available Before the emergence of Component-Based Frameworks, similar issues have been addressed by othersoftware development paradigms including e.g. Object-Oriented Programming (OOP, Component-Based Development (CBD, and Object-Oriented Framework. In this study, these approaches especiallyobject-oriented Frameworks are compared to Component-Based Frameworks and their relationship arediscussed. Different software reuse methods impacts on architectural patterns and support forapplication extensions and versioning. It is concluded that many of the mechanisms provided byComponent-Based Framework can be enabled by software elements at the lower level. The maincontribution of Component-Based Framework is the focus on Component development. All of them can bebuilt on each other in layered manner by adopting suitable design patterns. Still some things such aswhich method to develop and upgrade existing application to other approach.

  20. Tree-dependent Component Analysis

    OpenAIRE

    Bach, Francis R.; Jordan, Michael I.

    2012-01-01

    We present a generalization of independent component analysis (ICA), where instead of looking for a linear transform that makes the data components independent, we look for a transform that makes the data components well fit by a tree-structured graphical model. Treating the problem as a semiparametric statistical problem, we show that the optimal transform is found by minimizing a contrast function based on mutual information, a function that directly extends the contrast function used for c...

  1. On verification of software components

    OpenAIRE

    Basem Y. Alkazem

    2012-01-01

    Utilizing third party software components in the development of new systems became somewhat unfavourable approach among many organizations nowadays. This reluctance is primarily built due to the lack of support to verify the quality attributes of software components in order to avoid potential mismatches with systems requirements. This paper presents an approach to overcome this problem by providing a tool support to check component compatibility to a specification provided by developers. So,...

  2. Component separation in abdominal trauma

    OpenAIRE

    Rawstorne, Edward; Smart, Christopher J.; Fallis, Simon A.; Suggett, Nigel

    2014-01-01

    Component separation is established for complex hernia repairs. This case presents early component separation and release of the anterior and posterior sheath to facilitate closure of the abdominal wall following emergency laparotomy, reinforcing the repair with a biological mesh. On Day 11 following an emergency laparotomy for penetrating trauma, this patient underwent component separation and release of the anterior and posterior sheath. An intra-abdominal biological mesh was secured, and t...

  3. Application of Anisotropic Texture Components

    OpenAIRE

    Eschner, Th.; Fundenberger, J.-J.

    1997-01-01

    The description of textures in terms of texture components is an established conception in quantitative texture analysis. Recent developments lead to the representation of orientation distribution functions as a weighted sum of model functions, each corresponding to one anisotropic texture component. As was shown previously, an adequate texture description is possible with only a very small number of anisotropic texture components. As a result, textures and texture changes can be described by...

  4. Facets of Software Component Repository

    OpenAIRE

    Vaneet Kaur; Shivani Goel

    2011-01-01

    The software repository is used for storing, managing, and retrieving large numbers of software components. Repositories should be designed to meet the growing and changing needs of the software development organizations. Storage and representation of reusable software components in software repositories to assist retrieval is a key concern area. In this paper we have discussed various assets of thecomponent repository like component searching mechanisms and classifications such as Free Text,...

  5. Methods of component mode synthesis

    Science.gov (United States)

    Craig, R. R., Jr.

    1977-01-01

    A generalized substructure coupling, or component mode synthesis, procedure is described. Specific methods, applications, and such special topics as damping and experimental verification are surveyed.

  6. Component separation in abdominal trauma.

    Science.gov (United States)

    Rawstorne, Edward; Smart, Christopher J; Fallis, Simon A; Suggett, Nigel

    2014-01-01

    Component separation is established for complex hernia repairs. This case presents early component separation and release of the anterior and posterior sheath to facilitate closure of the abdominal wall following emergency laparotomy, reinforcing the repair with a biological mesh. On Day 11 following an emergency laparotomy for penetrating trauma, this patient underwent component separation and release of the anterior and posterior sheath. An intra-abdominal biological mesh was secured, and the fascia and skin closed successfully. Primary abdominal closure can be achieved in patients with penetrating abdominal trauma with the use of component separation and insertion of intra-abdominal biological mesh, where standard closure is not possible. PMID:24876334

  7. New titanium and titanium/hydroxyapatite coatings on ultra-high-molecular-weight polyethylene-in vitro osteoblastic performance

    International Nuclear Information System (INIS)

    The development of optimized hip joint materials is one of the most challenging opportunities in prosthetic technologies. In current approaches, ultra-high-molecular-weight polyethylene (UHMWPE) has been a favorite material for the acetabular component and, regarding the cementless technique, several coating options may be considered to contain and stabilize bearing surfaces and establish an improved interface with bone. In this work, newly developed constructs of UHMWPE coated with either commercially pure titanium (cpTi-UHMWPE), by DC magnetron sputtering, or with commercially pure titanium and hydroxyapatite (cpTi/HA-UHMWPE), by DC/RF magnetron co-sputtering, have been prepared and biologically characterized with human bone marrow-derived osteoblastic cultures. The cpTi-UHMWPE samples allowed a high cell growth and the expression of the complete osteoblastic phenotype, with high alkaline phosphatase activity, expression of osteogenic-associated genes and evident cell-mediated mineralization of the extracellular matrix. In comparison, the cpTi/HA-UHMWPE samples reported lower cell proliferation but earlier cell-mediated matrix mineralization. Accordingly, these newly developed systems may be suitable candidates to improve the osteointegration process in arthroplastic devices; nevertheless, further biological evaluation should be conducted.

  8. New titanium and titanium/hydroxyapatite coatings on ultra-high-molecular-weight polyethylene-in vitro osteoblastic performance

    Energy Technology Data Exchange (ETDEWEB)

    Silva, M A; Lopes, M A; Santos, J D; Fernandes, M H [Department of Metallurgical and Materials Engineering, Materials Section-Faculty of Engineering, University of Porto (Portugal); Gomes, P S [Laboratory of Pharmacology and Cellular Biocompatibility-Faculty of Dental Medicine, University of Porto (Portugal); Vila, M; Silva, R F, E-mail: mhfernandes@fmd.up.p [Department of Ceramics and Glass Engineering, University of Aveiro, CICECO (Portugal)

    2010-06-15

    The development of optimized hip joint materials is one of the most challenging opportunities in prosthetic technologies. In current approaches, ultra-high-molecular-weight polyethylene (UHMWPE) has been a favorite material for the acetabular component and, regarding the cementless technique, several coating options may be considered to contain and stabilize bearing surfaces and establish an improved interface with bone. In this work, newly developed constructs of UHMWPE coated with either commercially pure titanium (cpTi-UHMWPE), by DC magnetron sputtering, or with commercially pure titanium and hydroxyapatite (cpTi/HA-UHMWPE), by DC/RF magnetron co-sputtering, have been prepared and biologically characterized with human bone marrow-derived osteoblastic cultures. The cpTi-UHMWPE samples allowed a high cell growth and the expression of the complete osteoblastic phenotype, with high alkaline phosphatase activity, expression of osteogenic-associated genes and evident cell-mediated mineralization of the extracellular matrix. In comparison, the cpTi/HA-UHMWPE samples reported lower cell proliferation but earlier cell-mediated matrix mineralization. Accordingly, these newly developed systems may be suitable candidates to improve the osteointegration process in arthroplastic devices; nevertheless, further biological evaluation should be conducted.

  9. Connected Component Labeling Using Components Neighbors-Scan Labeling Approach

    Directory of Open Access Journals (Sweden)

    Akmal Rakhmadi

    2010-01-01

    Full Text Available Problem statement: Many approaches have been proposed in previous such as the classic sequential connected components labeling algorithm which is relies on two subsequent raster-scans of a binary image. This method produced good performance in terms of accuracy, but because of the implementation of the image processing systems now requires faster process of the computer, the speed of this technique’s process has become an important issue. Approach: A computational approach, called components neighbors-scan labeling algorithm for connected component labeling was presented in this study. This algorithm required scanning through an image only once to label connected components. The algorithm started by scanning from the head of the component’s group, before tracing all the components neighbors by using the main component’s information. This algorithm had desirable characteristics, it is simple while promoted accuracy and low time consuming. By using a table of components, this approach also gave other advantages as the information for the next higher process. Results: The approach had been tested with a collection of binary images. In practically all cases, the technique had successfully given the desired result. Averagely, from the results the algorithm increased the speed around 67.4% from the two times scanning method. Conclusion: Conclusion from the comparison with the previous method, the approach of components neighbors-scan for connected component labeling promoted speed, accuracy and simplicity. The results showed that the approach has a good performance in terms of accuracy, the time consumed and the simplicity of the algorithm.

  10. Components selection for ageing management

    International Nuclear Information System (INIS)

    Full text: The paper presents a synthesis of methods and activities realized for the selection of critical components to assure plant safety and availability (as electricity supplier). There are presented main criteria for selection, screening process. For the resulted categories of components shall be applied different category of maintenance (condition oriented, scheduled or corrective), function of the importance and financial effort necessary to fulfil the task. 1. Systems and components screening for plant safety assurance For the systems selection, from Safety point of view, was necessary first, to define systems which are dangerous in case of failure (mainly by rupture/ release of radioactivity) and the safety systems which have to mitigate the effects. This is realized based on accident analysis (from Safety Report). Also where taken in to account the 4 basic Safety Principles: 'Reactor shut down; Residual heat removal; Radioactivity products confinement; NPP status monitoring in normal and accident conditions'. Following step is to establish safety support systems, which have to action to assure main safety systems operation. This could be realized based on engineering judgement, or on PSA Level I analysis. Finally shall be realized chains of the support systems, which have to work, till primary systems. For the critical components selection, was realized a Failure Mode and Effect Analysis (FMEA), considering the components effects of failures, on system safety function. 2. Systems and components screening for plant availability assurance The work was realized in two steps: Systems screening; Components screening The systems screening, included: General, analyze of the plant systems list and the definition of those which clearly have to run continue to assure the nominal power; Realization of a complex diagram to define interdependence between the systems (e.g. PHT and auxiliaries, moderator and auxiliaries, plant electrical diagram); Fill of special

  11. APS beamline standard components handbook

    International Nuclear Information System (INIS)

    It is clear that most Advanced Photon Source (APS) Collaborative Access Team (CAT) members would like to concentrate on designing specialized equipment related to their scientific programs rather than on routine or standard beamline components. Thus, an effort is in progress at the APS to identify standard and modular components of APS beamlines. Identifying standard components is a nontrivial task because these components should support diverse beamline objectives. To assist with this effort, the APS has obtained advice and help from a Beamline Standardization and Modularization Committee consisting of experts in beamline design, construction, and operation. The staff of the Experimental Facilities Division identified various components thought to be standard items for beamlines, regardless of the specific scientific objective of a particular beamline. A generic beamline layout formed the basis for this identification. This layout is based on a double-crystal monochromator as the first optical element, with the possibility of other elements to follow. Pre-engineering designs were then made of the identified standard components. The Beamline Standardization and Modularization Committee has reviewed these designs and provided very useful input regarding the specifications of these components. We realize that there will be other configurations that may require special or modified components. This Handbook in its current version (1.1) contains descriptions, specifications, and pre-engineering design drawings of these standard components. In the future, the APS plans to add engineering drawings of identified standard beamline components. Use of standard components should result in major cost reductions for CATs in the areas of beamline design and construction

  12. Complement component 3 (C3)

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003539.htm Complement component 3 (C3) To use the sharing features on this page, ... be some throbbing. Why the Test is Performed C3 and C4 are the most commonly measured complement components. A complement test may be used to monitor ...

  13. Secure coupling of hardware components

    NARCIS (Netherlands)

    Knobbe, J.W.; Hoepman, J.H.; Joosten, H.J.M.

    2011-01-01

    A method and a system for securing communication between at least a first and a second hardware components of a mobile device is described. The method includes establishing a first shared secret between the first and the second hardware components during an initialization of the mobile device and, f

  14. Active components in food supplements

    NARCIS (Netherlands)

    Siemelink M; Jansen EHJM; Piersma AH; Opperhuizen A; LEO

    2000-01-01

    The growing food supplement market, where supplements are both more diverse and more easily available (e.g. through Internet) formed the backdrop to the inventory of the active components in food supplements. The safety of an increased intake of food components via supplements was also at issue her

  15. Unblockable Compositions of Software Components

    DEFF Research Database (Denmark)

    Dong, Ruzhen; Faber, Johannes; Liu, Zhiming;

    2012-01-01

    end, we develop an algorithm to compute the unblockable interaction behavior, called the interface model of a component, from its execution model. Based on this model, we introduce composition operators for the components and prove important compositionality results, showing the conditions under which...... composition of interface models preserves unblockable sequences of provided services....

  16. Revision arthroplasty using an anti-protrusio cage for Paprosky type Ⅲ acetabular bone deficiency:a middle-term follow-up%髋臼PaproskyⅢ型骨缺损髋臼加强杯翻修的中期疗效

    Institute of Scientific and Technical Information of China (English)

    黄强; 杨静; 沈彬; 周宗科; 康鹏德; 裴福兴

    2013-01-01

    目的 探讨髋臼Paprosky Ⅲ型骨缺损采用异体骨植骨结合髋臼加强杯翻修的中期临床疗效 方法 回顾性分析2002年1月至2009年12月采用髋臼加强杯翻修髋臼Paprosky Ⅲ型骨缺损患者的病历资料,19例(20髋)最终获得随访,男11例,女8例;年龄42~76岁,平均(57.4±6.4)岁.Paprosky ⅢA型7例(35%),ⅢB型13例(65%).平均随访(5.8±2.4)年.评价患者手术前后髋关节功能、术后髋臼加强杯的影像学稳定性和植骨效果.以髋臼加强杯失败为终点,采用Kaplan-Meier生存分析评价髋臼加强杯的五年生存率.结果 术前Harris髋关节评分为6~31分,平均(14.6±4.3)分,末次随访时为64~98分,平均(83.5±7.9)分.术前肢体平均短缩(26.3±9.1) mm,术后肢体平均短缩(1.2±3.4) mm.术前髋关节旋转中心相对于解剖旋转中心向上方平均移位(23.6±7.4) mm,向外平均移位(4.4±14.7)mm;术后关节旋转中心均恢复到Ranawat三角内.所有病例植入的异体骨均与宿主骨融合.无髋臼加强杯移位、螺钉断裂、进展性透亮线以及骨水泥断裂发生.3例(3髋)患者(15%)出现轻度骨吸收,未出现中度或重度骨吸收患者.髋形假体的五年生存率为100%(95%可信区间,0.95~1.0).结论 对于髋臼Paprosky Ⅲ型骨缺损采用异体骨植骨结合髋臼加强杯重建髋臼可获得较满意的中期翻修效果.%Objective To investigate the middle-term results of anti-protrusio cage combining with allograft bone graft for revision arthroplasty of Paprosky type Ⅲ acetabular bone defect.Methods A retrospective analysis was done for 19 patients (20 hips) with Paprosky type Ⅲ acetabular bone defect who received acetabular revisions using anti-protrusio cage from January 2002 to December 2009.There were 11 males and 8 females,aged from 42 to 76 years (average,57.4 years).There were 7 hips (35%) of Paprosky type ⅢA acetabular bone defect,and 13 hips (65%) of type ⅢB.The follow

  17. Component reliability for electronic systems

    CERN Document Server

    Bajenescu, Titu-Marius I

    2010-01-01

    The main reason for the premature breakdown of today's electronic products (computers, cars, tools, appliances, etc.) is the failure of the components used to build these products. Today professionals are looking for effective ways to minimize the degradation of electronic components to help ensure longer-lasting, more technically sound products and systems. This practical book offers engineers specific guidance on how to design more reliable components and build more reliable electronic systems. Professionals learn how to optimize a virtual component prototype, accurately monitor product reliability during the entire production process, and add the burn-in and selection procedures that are the most appropriate for the intended applications. Moreover, the book helps system designers ensure that all components are correctly applied, margins are adequate, wear-out failure modes are prevented during the expected duration of life, and system interfaces cannot lead to failure.

  18. Micromotions and wear of acetabular cup

    Czech Academy of Sciences Publication Activity Database

    Jíra, J.; Jírová, Jitka; Jiroušek, Ondřej; Micka, Michal

    Oxford : Elsevier, 2005 - (Ritchie, R.). s. 49-49 [International conference on mechanics of biomaterials and tissues /1./. 11.12.2005-15.12.2005, Waikoloa] R&D Projects: GA AV ČR(CZ) IAA200710504 Institutional research plan: CEZ:AV0Z20710524 Keywords : micromotions * UHMWPE wear * numerical analysis Subject RIV: FI - Traumatology, Orthopedics

  19. Early Defect Detection of Acetabular Implants

    Czech Academy of Sciences Publication Activity Database

    Kytýř, Daniel; Jiroušek, Ondřej; Zlámal, Petr; Doktor, Tomáš; Jandejsek, I.

    Prague : ITAM AS CR, 2012 - (Náprstek, J.; Fischer, C.), s. 825-834 ISBN 978-80-86246-40-6. [Engineering Mechanics 2012 /18./. Svratka (CZ), 14.05.2012-17.05.2012] R&D Projects: GA ČR(CZ) GAP105/10/2305 Institutional support: RVO:68378297 Keywords : bone-cement interface * computed tomography * crack detection * hip simulator Subject RIV: FI - Traumatology, Orthopedics http://www.engmech.cz/

  20. Apparatus for remotely handling components

    Science.gov (United States)

    Szkrybalo, Gregory A.; Griffin, Donald L.

    1994-01-01

    The inventive apparatus for remotely handling bar-like components which define a longitudinal direction includes a gripper mechanism for gripping the component including first and second gripper members longitudinally fixedly spaced from each other and oriented parallel to each other in planes transverse to the longitudinal direction. Each gripper member includes a jaw having at least one V-groove with opposing surfaces intersecting at a base and extending radially relative to the longitudinal direction for receiving the component in an open end between the opposing surfaces. The V-grooves on the jaw plate of the first and second gripper members are aligned in the longitudinal direction to support the component in the first and second gripper members. A jaw is rotatably mounted on and a part of each of the first and second gripper members for selectively assuming a retracted mode in which the open end of the V-groove is unobstructed and active mode in which the jaw spans the open end of the V-groove in the first and second gripper members. The jaw has a locking surface for contacting the component in the active mode to secure the component between the locking surface of the jaw and the opposing surfaces of the V-groove. The locking surface has a plurality of stepped portions, each defining a progressively decreasing radial distance between the base of the V-groove and the stepped portion opposing the base to accommodate varying sizes of components.

  1. Vacuum Brazing of Accelerator Components

    Science.gov (United States)

    Singh, Rajvir; Pant, K. K.; Lal, Shankar; Yadav, D. P.; Garg, S. R.; Raghuvanshi, V. K.; Mundra, G.

    2012-11-01

    Commonly used materials for accelerator components are those which are vacuum compatible and thermally conductive. Stainless steel, aluminum and copper are common among them. Stainless steel is a poor heat conductor and not very common in use where good thermal conductivity is required. Aluminum and copper and their alloys meet the above requirements and are frequently used for the above purpose. The accelerator components made of aluminum and its alloys using welding process have become a common practice now a days. It is mandatory to use copper and its other grades in RF devices required for accelerators. Beam line and Front End components of the accelerators are fabricated from stainless steel and OFHC copper. Fabrication of components made of copper using welding process is very difficult and in most of the cases it is impossible. Fabrication and joining in such cases is possible using brazing process especially under vacuum and inert gas atmosphere. Several accelerator components have been vacuum brazed for Indus projects at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore using vacuum brazing facility available at RRCAT, Indore. This paper presents details regarding development of the above mentioned high value and strategic components/assemblies. It will include basics required for vacuum brazing, details of vacuum brazing facility, joint design, fixturing of the jobs, selection of filler alloys, optimization of brazing parameters so as to obtain high quality brazed joints, brief description of vacuum brazed accelerator components etc.

  2. Vacuum Brazing of Accelerator Components

    International Nuclear Information System (INIS)

    Commonly used materials for accelerator components are those which are vacuum compatible and thermally conductive. Stainless steel, aluminum and copper are common among them. Stainless steel is a poor heat conductor and not very common in use where good thermal conductivity is required. Aluminum and copper and their alloys meet the above requirements and are frequently used for the above purpose. The accelerator components made of aluminum and its alloys using welding process have become a common practice now a days. It is mandatory to use copper and its other grades in RF devices required for accelerators. Beam line and Front End components of the accelerators are fabricated from stainless steel and OFHC copper. Fabrication of components made of copper using welding process is very difficult and in most of the cases it is impossible. Fabrication and joining in such cases is possible using brazing process especially under vacuum and inert gas atmosphere. Several accelerator components have been vacuum brazed for Indus projects at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore using vacuum brazing facility available at RRCAT, Indore. This paper presents details regarding development of the above mentioned high value and strategic components/assemblies. It will include basics required for vacuum brazing, details of vacuum brazing facility, joint design, fixturing of the jobs, selection of filler alloys, optimization of brazing parameters so as to obtain high quality brazed joints, brief description of vacuum brazed accelerator components etc.

  3. Fixation method does not affect restoration of rotation center in hip replacements: A single-site retrospective study

    Directory of Open Access Journals (Sweden)

    Wegner Alexander

    2012-06-01

    Full Text Available Abstract Background Aseptic loosening is one of the greatest problems in hip replacement surgery. The rotation center of the hip is believed to influence the longevity of fixation. The aim of this study was to compare the influence of cemented and cementless cup fixation techniques on the position of the center of rotation because cemented cup fixation requires the removal of more bone for solid fixation than the cementless technique. Methods We retrospectively compared pre- and post-operative positions of the hip rotation center in 25 and 68 patients who underwent artificial hip replacements in our department in 2007 using cemented or cementless cup fixation, respectively, with digital radiographic image analysis. Results The mean horizontal and vertical distances between the rotation center and the acetabular teardrop were compared in radiographic images taken pre- and post-operatively. The mean horizontal difference was −2.63 mm (range: -11.00 mm to 10.46 mm, standard deviation 4.23 mm for patients who underwent cementless fixation, and −2.84 mm (range: -10.87 to 5.30 mm, standard deviation 4.59 mm for patients who underwent cemented fixation. The mean vertical difference was 0.60 mm (range: -20.15 mm to 10.00 mm, standard deviation 3.93 mm and 0.41 mm (range: -9.26 mm to 6.54 mm, standard deviation 3.58 mm for the cementless and cemented fixation groups, respectively. The two fixation techniques had no significant difference on the position of the hip rotation center in the 93 patients in this study. Conclusions The hip rotation center was similarly restored using either the cemented or cementless fixation techniques in this patient cohort, indicating that the fixation technique itself does not interfere with the position of the center of rotation. To completely answer this question further studies with more patients are needed.

  4. Bacterial contamination of blood components.

    Science.gov (United States)

    Seghatchian, J

    2001-10-01

    Despite considerable advances in the safety of blood components, transfusion associated bacterial infection (TABI) remains an unresolved problem. As yet there are no perfect preventative, screening and/or detection methodologies for eliminating contaminated units. Until a practical, rapid, cost-effective and logistically acceptable test becomes available, we should be satisfied with the choice of various limited solutions that at least partially improve the bacterial safety of blood components. It is also necessary to establish standardised guidelines and agreed upon systematic procedures for the recognition and reporting of the laboratory and clinical evaluation of adverse reactions in recipients of contaminated blood components. PMID:11761277

  5. Electronic components, tubes and transistors

    CERN Document Server

    Dummer, G W A

    1965-01-01

    Electronic Components, Tubes and Transistors aims to bridge the gap between the basic measurement theory of resistance, capacitance, and inductance and the practical application of electronic components in equipments. The more practical or usage aspect of electron tubes and semiconductors is given emphasis over theory. The essential characteristics of each main type of component, tube, and transistor are summarized. This book is comprised of six chapters and begins with a discussion on the essential characteristics in terms of the parameters usually required in choosing a resistor, including s

  6. Composite components on commercial aircraft

    Science.gov (United States)

    Dexter, H. B.

    1980-01-01

    The paper considers the use of composite components in commercial aircraft. NASA has been active in sponsoring flight service programs with advanced composites for the last 10 years, with 2.5 million total composite component hours accumulated since 1970 on commercial transports and helicopters with no significant degradation in residual strength of composite components. Design, inspection, and maintenance procedures have been developed; a major NASA/US industry technology program has been developed to reduce fuel consumption of commercial transport aircraft through the use of advanced composites.

  7. Ceramic components for MHD electrode

    Science.gov (United States)

    Marchant, D.D.

    A ceramic component which exhibits electrical conductivity down to near room temperatures has the formula: Hf/sub x/In/sub y/A/sub z/O/sub 2/ where x = 0.1 to 0.4, y = 0.3 to 0.6, z = 0.1 to 0.4 and A is a lanthanide rare earth or yttrium. The component is suitable for use in the fabrication of MHD electrodes or as the current leadout portion of a composite electrode with other ceramic components.

  8. Metallurgical Laboratory and Components Testing

    Data.gov (United States)

    Federal Laboratory Consortium — In the field of metallurgy, TTC is equipped to run laboratory tests on track and rolling stock components and materials. The testing lab contains scanning-electron,...

  9. Ageing of zirconium alloy components

    International Nuclear Information System (INIS)

    India has two types (pressurized heavy water reactors (PHWRs) and boiling water reactors (BWRs)) of commercial nuclear reactors in operation, in addition to research reactors. Many of the life limiting critical components in these reactors are fabricated from zirconium alloys. The progressive degradation of these components caused by the cumulative exposure of high energy neutron irradiation with increasing period of reactor operation was monitored to assess the degree of ageing. The components/specimens examined included fuel element claddings removed from BWRs, pressure tubes and garter springs removed from PHWRs and calandria tube specimens used in PHWRs. The tests included tension test (for cladding, garter spring), fracture toughness test (for pressure tube), crush test (for garter spring), and measurement of irradiation induced growth (for calandria tube). Results of various tests conducted are presented and applications of the test results are elaborated for residual life estimation/life extension of the components

  10. US LMFBR coolant system components

    International Nuclear Information System (INIS)

    Development and use of LMFBR coolant system components in the United States has progressed through more than two decades, with both the government and private sectors participating significantly in the support and conduct of the work. The purpose of this paper is to present the major functional requirements that these components are expected to meet, their current status and future direction of development, and recent test results. The components to be discussed are: (1) primary and intermediate system large sodium piping; (2) primary and intermediate system large sodium valves; (3) primary and intermediate main sodium pumps; (4) intermediate heat exchanger (IHX); and (5) sodium-heated steam generators. The major near-term activities associated with the above components are focused primarily on the Fast Flux Test Facility (FFTF), the Clinch River Breeder Reactor Plant (CRBRP), and the anticipated commercial LMFBR's

  11. Principles of Principal Component Analysis

    OpenAIRE

    Durham, Catherine A.; King, Robert P.

    2010-01-01

    With increasing frequency consumer studies are supplementing demographic and price variables with responses to an extended set of Likert-scale questions to elicit information on consumer motivations and attitudes. Principal compo­nent analysis (PCA) is a statistical tool that reduces a large number of variables to a smaller set of "components" that describe as much as possible of the variation in the original variables. Attitudinal responses can then be represented by component scores in sta...

  12. Plasmonic components fabrication via nanoimprint

    DEFF Research Database (Denmark)

    Boltasseva, Alexandra

    2009-01-01

    A review report on nanoimprinted plasmonic components is given. The fabrication of different metal–dielectric geometries and nanostructured surfaces that support either propagating or localized surface plasmon modes is discussed. The main characteristics and advantages of the nanoimprint technolo...... surfaces for enhanced transmission studies and sensor applications is also discussed. Throughout the report, the main fabrication schemes are described, as well as the challenges facing future manufacturing of plasmonic components for device applications....

  13. Formal aspects of component software

    OpenAIRE

    Sun, Meng; Schatz, B.

    2014-01-01

    This issue includes extended versions of selected best papers from the 7th International Workshop on Formal Aspects of Component Software (FACS 2010) held in Guimarães, Portugal on October 14–16, 2010. The component-based software development approach has emerged as a promising paradigm to cope with an ever increasing complexity of present-day software solutions by bringing sound production and engineering principles into software engineering. However, many conceptual and technological iss...

  14. RELATIVE PRINCIPLE COMPONENT AND RELATIVE PRINCIPLE COMPONENT ANALYSIS ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    Wen Chenglin; Wang Tianzhen; Hu Jing

    2007-01-01

    In this letter, the new concept of Relative Principle Component (RPC) and method of RPC Analysis (RPCA) are put forward. Meanwhile, the concepts such as Relative Transform (RT), Rotundity Scatter (RS) and so on are introduced. This new method can overcome some disadvantages of the classical Principle Component Analysis (PCA) when data are rotundity scatter. The RPC selected by RPCA are more representative, and their significance of geometry is more notable, so that the application of the new algorithm will be very extensive. The performance and effectiveness are simply demonstrated by the geometrical interpretation proposed.

  15. Component protection based automatic control

    International Nuclear Information System (INIS)

    Control and safety systems as well as operation procedures are designed on the basis of critical process parameters limits. The expectation is that short and long term mechanical damage and process failures will be avoided by operating the plant within the specified constraints envelopes. In this paper, one of the Advanced Liquid Metal Reactor (ALMR) design duty cycles events is discussed to corroborate that the time has come to explicitly make component protection part of the control system. Component stress assessment and aging data should be an integral part of the control system. Then transient trajectory planning and operating limits could be aimed at minimizing component specific and overall plant component damage cost functions. The impact of transients on critical components could then be managed according to plant lifetime design goals. The need for developing methodologies for online transient trajectory planning and assessment of operating limits in order to facilitate the explicit incorporation of damage assessment capabilities to the plant control and protection systems is discussed. 12 refs

  16. Automated cleaning of electronic components

    International Nuclear Information System (INIS)

    Environmental and operator safety concerns are leading to the elimination of trichloroethylene and chlorofluorocarbon solvents in cleaning processes that remove rosin flux, organic and inorganic contamination, and particulates from electronic components. Present processes depend heavily on these solvents for manual spray cleaning of small components and subassemblies. Use of alternative solvent systems can lead to longer processing times and reduced quality. Automated spray cleaning can improve the quality of the cleaning process, thus enabling the productive use of environmentally conscious materials, while minimizing personnel exposure to hazardous materials. We describe the development of a prototype robotic system for cleaning electronic components in a spray cleaning workcell. An important feature of the prototype system is the capability to generate the robot paths and motions automatically from the CAD models of the part to be cleaned, and to embed cleaning process knowledge into the automatically programmed operations

  17. Towards Prognostics for Electronics Components

    Science.gov (United States)

    Saha, Bhaskar; Celaya, Jose R.; Wysocki, Philip F.; Goebel, Kai F.

    2013-01-01

    Electronics components have an increasingly critical role in avionics systems and in the development of future aircraft systems. Prognostics of such components is becoming a very important research field as a result of the need to provide aircraft systems with system level health management information. This paper focuses on a prognostics application for electronics components within avionics systems, and in particular its application to an Isolated Gate Bipolar Transistor (IGBT). This application utilizes the remaining useful life prediction, accomplished by employing the particle filter framework, leveraging data from accelerated aging tests on IGBTs. These tests induced thermal-electrical overstresses by applying thermal cycling to the IGBT devices. In-situ state monitoring, including measurements of steady-state voltages and currents, electrical transients, and thermal transients are recorded and used as potential precursors of failure.

  18. Modelling of power system components

    CERN Document Server

    Murty, PSR

    2008-01-01

    Relationsof Power System Components is a prerequisite course for the Study of Power System Analysis, Operation and control. Models for several electric power network components are not readily available for dynamic studies. In this book these models are presented in a lucid way. In chapter 1 per Unit Relations and primitive network models are reviewed. Chapter 2 deals with graph theory that is relevant to various incidence Matrices required in network modeling and these different incidence matrices are presented in Chapter 3. In chapter 4 the various methods of obtaining network matrices in bo

  19. Radioactive resistance of EEPROM components

    International Nuclear Information System (INIS)

    The aim of this paper is to examine the resistance of EEPROM components under the influence of gamma radiation. This paper is significant for military industry and space technology. Therefore the analysis of the degradation mechanisms of these components as well as the possibilities to increase their radiation resistance have been considered by many authors. Total dose results are presented for 28C64C EEPROM there is evidence that the first failure appeared for 1000 Gy total dose level. The obtained result are analyzed and explained theoretically via the interaction of gamma radiation with oxide layer. (author)

  20. Space storable propulsion components development

    Science.gov (United States)

    Hagler, R., Jr.

    1982-01-01

    The current development status of components to control the flow of propellants (liquid fluorine and hydrazine) in a demonstration space storable propulsion system is discussed. The criteria which determined the designs for the pressure regulator, explosive-actuated valves, propellant shutoff valve, latching solenoid-actuated valve and propellant filter are presented. The test philosophy that was followed during component development is outlined. The results from compatibility demonstrations for reusable connectors, flange seals, and CRES/Ti-6Al4V transition tubes and the evaluations of processes for welding (hand-held TIG, automated TIG, and EB), cleaning for fluorine service, and decontamination after fluorine exposure are described.

  1. Formal Component-Based Semantics

    CERN Document Server

    Madlener, Ken; van Eekelen, Marko; 10.4204/EPTCS.62.2

    2011-01-01

    One of the proposed solutions for improving the scalability of semantics of programming languages is Component-Based Semantics, introduced by Peter D. Mosses. It is expected that this framework can also be used effectively for modular meta theoretic reasoning. This paper presents a formalization of Component-Based Semantics in the theorem prover Coq. It is based on Modular SOS, a variant of SOS, and makes essential use of dependent types, while profiting from type classes. This formalization constitutes a contribution towards modular meta theoretic formalizations in theorem provers. As a small example, a modular proof of determinism of a mini-language is developed.

  2. Component Reification in Systems Modelling

    DEFF Research Database (Denmark)

    Bendisposto, Jens; Hallerstede, Stefan

    When modelling concurrent or distributed systems in Event-B, we often obtain models where the structure of the connected components is specified by constants. Their behaviour is specified by the non-deterministic choice of event parameters for events that operate on shared variables. From a certa...

  3. Opinions about Component Energetic Security

    OpenAIRE

    Elena GOLUMBEANU (GEORGESCU)

    2012-01-01

    Collective security (international) represent the morphological expression of individual security components. According to the Report presented at the United Nations Development Programme, collective security (international) as well as national security, is the expression of seven synergistic dimensions as follows: economic security, food security, environmental security, personal security, community security, political security and individual security. As part of economic security, energy an...

  4. Fractionalization of graphitic reactor components

    International Nuclear Information System (INIS)

    Within the scope of this project, a stock taking took place that comprised graphic components in German research and prototype reactors. From a long set of experiments mechanical breaking was determined to represent the optimal solution for the problem of fractionalizing graphitic components with a reasonable tritium content. Be sides the very low dust emission and the total lack of secondary waste emission, the small and mobile tool are outstanding advantages of this technique. Graphitic dust which was emitted throughout the different experiments was characterized and analyzed with respect to its explosion properties. Choosing the right conditions, a graphite dust explosion can safety be expelled during the trials on activated graphite. Successful fractionalization experiments performed on activated graphite clearly show that a planar mechanical breaking of graphite as well as a yawing of graphitic components is possible. The performance of the filter installation is evidenced by the fact that all tools and components - with exception of the filters themselves - applied during the experiments could be decontaminated and measured for free release. (orig.)

  5. Fabrication of plastic microfluidic components

    Science.gov (United States)

    Martin, Peter M.; Matson, Dean W.; Bennett, Wendy D.; Hammerstrom, D. J.

    1998-09-01

    Plastic components have many advantages, including ease of fabrication, low cost, chemical inertness, lightweight, and disposability. We report on the fabrication of three plastics-based microfluidic components: a motherboard, a dialysis unit, and a metal sensor. Microchannels, headers, and interconnects were produced in thin sheets (>=50 microns) of polyimide, PMMA, polyethylene, and polycarbonate using a direct-write excimer laser micromachining system. Machined sheets were laminated by thermal and adhesive bonding to form leak-tight microfluidic components. The microfluidic motherboard borrowed the `functionality on a chip' concept from the electronics industry and was the heart of a complex microfluidic analytical device. The motherboard platform was designed to be tightly integrated and self-contained (i.e., liquid flows are all confined within machined microchannels), reducing the need for tubing with fluid distribution and connectivity. This concept greatly facilitated system integration and miniaturization. As fabricated, the motherboard consisted of three fluid reservoirs connected to micropumps by microchannels. The fluids could either be pumped independently or mixed in microchannels prior to being directed to exterior analytical components via outlet ports. The microdialysis device was intended to separate electrolytic solutes from low volume samples prior to mass spectrometric analysis. The device consisted of a dialysis membrane laminated between opposed serpentine microchannels containing the sample fluid and a buffer solution. The laminated metal sensor consisted of fluid reservoirs, micro-flow channels, micropumps, mixing channels, reaction channels, and detector circuitry.

  6. Nitrogen laser with additional components

    International Nuclear Information System (INIS)

    The development and construction of a Nitrogen laser with low cost domestic components is described. The model built is operated at 50 pulses per second with a 50 kW power per pulse at the ultraviolet 337.1 nm wavelength. (Author)

  7. Factor Analysis via Components Analysis

    Science.gov (United States)

    Bentler, Peter M.; de Leeuw, Jan

    2011-01-01

    When the factor analysis model holds, component loadings are linear combinations of factor loadings, and vice versa. This interrelation permits us to define new optimization criteria and estimation methods for exploratory factor analysis. Although this article is primarily conceptual in nature, an illustrative example and a small simulation show…

  8. Factor Analysis via Components Analysis

    OpenAIRE

    Bentler, Peter M.; Jan de Leeuw

    2011-01-01

    Under the null hypothesis, component loadings are linear combinations of factor loadings, and vice versa. This interrelation permits defining new optimization criteria and estimation methods for exploratory factor analysis. Although this note is primarily conceptual in nature, an illustrative example shows the methodology to be promising.

  9. Inspection of disposal canisters components

    International Nuclear Information System (INIS)

    This report presents the inspection techniques of disposal canister components. Manufacturing methods and a description of the defects related to different manufacturing methods are described briefly. The defect types form a basis for the design of non-destructive testing because the defect types, which occur in the inspected components, affect to choice of inspection methods. The canister components are to nodular cast iron insert, steel lid, lid screw, metal gasket, copper tube with integrated or separate bottom, and copper lid. The inspection of copper material is challenging due to the anisotropic properties of the material and local changes in the grain size of the copper material. The cast iron insert has some acoustical material property variation (attenuation, velocity changes, scattering properties), which make the ultrasonic inspection demanding from calibration point of view. Mainly three different methods are used for inspection. Ultrasonic testing technique is used for inspection of volume, eddy current technique, for copper components only, and visual testing technique are used for inspection of the surface and near surface area

  10. Components of Co-creation

    DEFF Research Database (Denmark)

    Tanev, Stoyan

    2009-01-01

    . However, these typically focus on the study, discussion and analysis of a small number of cases using deep, ethnographic description of their practices aiming at conceptualization and categorization of the different types of interactions between end users, the firm and the value network. Although useful...... the benefits of both qualitative and quantitative research approaches for studying the nature of value co-creation. The article provides a first attempt to identify the main research steps of such a methodology. It provides some preliminary results on the key components of value co-creation between firms...... and end customers based on the application of web search and Principal Component Analysis (PCA) techniques. The analysis of these preliminary results is then used as an opportunity to identify a number of research questions to be addressed in future research. The emerging research questions follow...

  11. Cylinder components properties, applications, materials

    CERN Document Server

    2016-01-01

    Owing to the ever-increasing requirements to be met by gasoline and diesel engines in terms of CO2 reduction, emission behavior, weight, and service life, a comprehensive understanding of combustion engine components is essential today. It is no longer possible for professionals in automotive engineering to manage without the corresponding expertise, whether they work in the field of design, development, testing, or maintenance. This technical book provides in-depth answers to questions about design, production, and machining of cylinder components. In this second edition, every section has been revised and expanded to include the latest developments in the combustion engine. Content Piston rings Piston pins and piston pin circlips Bearings Connecting rods Crankcase and cylinder liners Target audience Engineers in the field of engine development and maintenanceLecturers and students in the areas of mechanical engineering, engine technology, and vehicle constructionAnyone interested in technology Publisher MAH...

  12. Tritium in fusion reactor components

    International Nuclear Information System (INIS)

    When tritium is used in a fusion energy experiment or reactor, several implications affect and usually restrict the design and operation of the system and involve questions of containment, inventory, and radiation damage. Containment is expected to be particularly important both for high-temperature components and for those components that are prone to require frequent maintenance. Inventory is currently of major significance in cases where safety and environmental considerations limit the experiments to very low levels of tritium. Fewer inventory restrictions are expected as fusion experiments are placed in more-remote locations and as the fusion community gains experience with the use of tritium. However, the advent of power-producing experiments with high-duty cycle will again lead to serious difficulties based principally on tritium availability; cyclic operations with significant regeneration times are the principal problems

  13. Centrifugal slip casting of components

    International Nuclear Information System (INIS)

    Research in layered and functionally gradient materials has emerged because of the increasing demand for high-performance engineering materials. Many techniques have been used to produce layered and functionally gradient components. Common examples include thermal spray processing, powder processing, chemical and physical vapor deposition, high-temperature or combustion synthesis, diffusion treatments, microwave processing and infiltration. Of these techniques, powder processing routes offer excellent microstructural control and product quality, and they are capable of producing large components. Centrifugal slip casting is a powder-processing technique combining the effects of slip casting and centrifugation. In slip casting, consolidation takes place as fluid is removed by the porous mold. Particles within the slip move with the suspending fluid until reaching the mold wall, at which point they are consolidated. In centrifugation, particles within the slip move through the fluid at a rate dependent upon the gravitational force and particle drag

  14. Modelling Livestock Component in FSSIM

    OpenAIRE

    Thorne, P.J.; Hengsdijk, H.; Janssen, S.J.C.; Louhichi, K.; Keulen, van, M.; Thornton, P.K.

    2009-01-01

    This document summarises the development of a ruminant livestock component for the Farm System Simulator (FSSIM). This includes treatments of energy and protein transactions in ruminant livestock that have been used as a basis for the biophysical simulations that will generate the input production parameters for FSSIM. The treatments are derived principally from the “French” feed evaluation and rationing system for protein and energy. Currently, we have constructed routines that are capable o...

  15. Substructuring and Component Mode Synthesis

    Directory of Open Access Journals (Sweden)

    P. Seshu

    1997-01-01

    Full Text Available Substructuring and component mode synthesis (CMS, is a very popular method of model reduction for large structural dynamics problems. Starting from the pioneering works on this technique in the early 1960s, many researchers have studied and used this technique in a variety of applications. Besides model reduction, CMS offers several other crucial advantages. The present work aims to provide a review of the available literature on this important technique.

  16. Substructuring and Component Mode Synthesis

    OpenAIRE

    Seshu, P.

    1997-01-01

    Substructuring and component mode synthesis (CMS), is a very popular method of model reduction for large structural dynamics problems. Starting from the pioneering works on this technique in the early 1960s, many researchers have studied and used this technique in a variety of applications. Besides model reduction, CMS offers several other crucial advantages. The present work aims to provide a review of the available literature on this important technique.

  17. Two-component Dirac equation

    OpenAIRE

    Luo, Da-Wei; Pyshkin, P. V.; Yu, Ting; Lin, Hai-Qing; You, J. Q.; Wu, Lian-Ao

    2016-01-01

    We provide an alternative approach to relativistic dynamics based on the Feshbach projection technique. Instead of directly studying the Dirac equation, we derive a two-component equation for the upper spinor. This approach allows one to investigate the underlying physics in a different perspective. For particles with small mass such as the neutrino, the leading order equation has a Hermitian effective Hamiltonian, implying there is no leakage between the upper and lower spinors. In the weak ...

  18. NAT: perspectives for cellular components.

    Science.gov (United States)

    Barbara, J A

    1999-12-01

    The introduction of routine testing to detect viral genomes in donated blood was originally driven by requirements for plasma fractionation in relation to exclusion of hepatitis C virus (HCV) RNA. Nevertheless, it was obvious from the outset that a dual standard for fractionated products and individual blood components would be untenable. In many countries therefore, planning for introduction of nucleic acid testing (NAT) of blood incorporated progression to release of HCV RNA tested components. HCV was singled out because of its long seronegative 'window period', relatively high prevalence and incidence in blood donors, rapid burst time and high genome copy number during seroconversion. The latter properties made HCV particularly suitable for detection in pools of samples. If HCV RNA testing is required for release of labile components such as platelets, rapid provision of NAT results is vital because of short shelf life of platelets and the problems of delays when resolving the infectious unit in a reactive pool. For NAT release of labile components smaller sample pool sizes allow faster resolution of RNA positive units. Smaller pools involve high test throughput, the likely need for more testing laboratories and ensuing increased costs. Single sample testing is the ultimate extrapolation of reducing sample pool size. With reduced pool sizes or single sample testing, the option of testing for other viruses (e.g. HIV or HBV) singly or in multiplex also arises. The cost-benefit and incremental yield of such strategies in the light of 'combo' assays for HIV Ag/Ab and the recently described HCV Ag assay will require careful and objective assessment, together with re-appraisal of anti-HBc screening for detection of HBV infected donors at the "tail-end" of carriage. PMID:10686060

  19. Bounding Component Behavior via Protocols

    Czech Academy of Sciences Publication Activity Database

    Plášil, František; Višňovský, Stanislav; Besta, Miloslav

    Los Alamitos : IEEE Computer Society, 1999 - (Firesmith, D.; Riehle, R.; Pour, G.; Meyer, B.), s. 387-398 ISBN 0-7695-0278-4. [TOOLS /30./. Santa Barbara (US), 01.08.1999-05.08.1999] R&D Projects: GA AV ČR IAA2030902; GA ČR GA201/99/0244 Institutional research plan: AV0Z1030915 Keywords : software components * behavior protocols * software architecture Subject RIV: JC - Computer Hardware ; Software

  20. ITER plasma-facing components

    Energy Technology Data Exchange (ETDEWEB)

    Merola, Mario, E-mail: mario.merola@iter.or [ITER Organization, CS 90 046, 13067 St Paul-lez-Durance Cedex (France); Loesser, D. [Blanket Integrated Product Team, Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 (United States); Martin, A.; Chappuis, P.; Mitteau, R.; Komarov, V.; Pitts, R.A.; Gicquel, S.; Barabash, V.; Giancarli, L.; Palmer, J.; Nakahira, M.; Loarte, A.; Campbell, D.; Eaton, R.; Kukushkin, A.; Sugihara, M.; Zhang, F.; Kim, C.S.; Raffray, R. [ITER Organization, CS 90 046, 13067 St Paul-lez-Durance Cedex (France)

    2010-12-15

    The ITER plasma-facing components directly face the thermonuclear plasma and include the divertor, the blanket and the test blanket modules with their corresponding frames. The divertor is located at the bottom of the plasma chamber and is aimed at exhausting the major part of the plasma thermal power (including alpha power) and at minimising the helium and impurity content in the plasma. The blanket system provides a physical boundary for the plasma transients and contributes to the thermal and nuclear shielding of the vacuum vessel and external machine components. It consists of modular shielding elements known as blanket modules which are attached to the vacuum vessel. Each blanket module consists of two major components: a plasma-facing first wall panel and a shield block. The test blanket modules are mock-ups of DEMO breeding blankets. There are three ITER equatorial ports devoted to test blanket modules, each of them providing for the allocation of two breeding modules inserted in a steel frame and in front of a shield block.

  1. ITER plasma-facing components

    International Nuclear Information System (INIS)

    The ITER plasma-facing components directly face the thermonuclear plasma and include the divertor, the blanket and the test blanket modules with their corresponding frames. The divertor is located at the bottom of the plasma chamber and is aimed at exhausting the major part of the plasma thermal power (including alpha power) and at minimising the helium and impurity content in the plasma. The blanket system provides a physical boundary for the plasma transients and contributes to the thermal and nuclear shielding of the vacuum vessel and external machine components. It consists of modular shielding elements known as blanket modules which are attached to the vacuum vessel. Each blanket module consists of two major components: a plasma-facing first wall panel and a shield block. The test blanket modules are mock-ups of DEMO breeding blankets. There are three ITER equatorial ports devoted to test blanket modules, each of them providing for the allocation of two breeding modules inserted in a steel frame and in front of a shield block.

  2. Aging risk of passive components

    International Nuclear Information System (INIS)

    This paper presents an approach for determining the increasing failure probability of an aging passive component and for calculating its resulting effect on plant risk by modifying an existing commercial nuclear reactor probabilistic risk assessment (PRA). A technique was developed for introducing aging into failure probability calculations using probabilistic structural analysis (PSA) techniques. Various probabilistic structural analysis methods were reviewed, and the PRAISE computer code was selected to perform the PSA. A component was selected that could fail and have a significant effect on the risk of core damage frequency. This component is a weld in the auxiliary feedwater system (AFW) of a pressurized water reactor (PWR). The stress on the AFW weld, for input in PRAISE, was determined for piping design loads, plant transient loads, and a thermal cyclic load that could cause crack growth and ultimate pipe failure. One PRAISE calculation might be made with the possibility of water hammer introduced to determine the effect on core damage frequency. An existing PRA (for a NUREG 1150 plant) was modified to include the failure of the AFW weld. Because this work is not complete, only preliminary conclusions and recommendations are presented

  3. Fusion-component lifetime analysis

    International Nuclear Information System (INIS)

    A one-dimensional computer code has been developed to examine the lifetime of first-wall and impurity-control components. The code incorporates the operating and design parameters, the material characteristics, and the appropriate failure criteria for the individual components. The major emphasis of the modeling effort has been to calculate the temperature-stress-strain-radiation effects history of a component so that the synergystic effects between sputtering erosion, swelling, creep, fatigue, and crack growth can be examined. The general forms of the property equations are the same for all materials in order to provide the greatest flexibility for materials selection in the code. The individual coefficients within the equations are different for each material. The code is capable of determining the behavior of a plate, composed of either a single or dual material structure, that is either totally constrained or constrained from bending but not from expansion. The code has been utilized to analyze the first walls for FED/INTOR and DEMO and to analyze the limiter for FED/INTOR

  4. Towards Dependable Emergent Ensembles of Components: The DEECo Component Model

    Czech Academy of Sciences Publication Activity Database

    Keznikl, J.; Bureš, T.; Plášil, František; Kit, M.

    Los Alamitos: IEEE CS, 2012 - (Babar, M.; Cuesta, C.; Savolainen, J.; Männistö, T.), s. 249-252 ISBN 978-0-7695-4827-2. [WICSA / ECSA 2012. Joint Working Conference on Software Architecture /10./ & European Conference on Software Architecture /6./. Helsinki (FI), 20.08.2012-24.08.2012] EU Projects: European Commission(XE) ASCENS 257414 Grant ostatní: GA AV ČR(CZ) GAP202/11/0312; MFF UK(CZ) SVV-2012-265312 Institutional support: RVO:67985807 Keywords : component * ensemble * adaptation * dynamic architecture * implicit communication * implicit bindings Subject RIV: JC - Computer Hardware ; Software

  5. SCAM – Software Component Assessment Model

    OpenAIRE

    Hasan Tahir; Aasia Khannum; Ruhma Tahir

    2011-01-01

    It is widely understood that component based development is different from conventional development because components offer accelerated growth. In the absence of an effective component assessment strategy the developers of a software project have no way of assessing the quality of the software component they are about to incorporate into the project. We present two laws that link software components, software projects and their quality. We further propose a simple software component assessme...

  6. Web components and the semantic web

    OpenAIRE

    Casey, Maire; Pahl, Claus

    2003-01-01

    Component-based software engineering on the Web differs from traditional component and software engineering. We investigate Web component engineering activites that are crucial for the development,com position, and deployment of components on the Web. The current Web Services and Semantic Web initiatives strongly influence our work. Focussing on Web component composition we develop description and reasoning techniques that support a component developer in the composition activities,fo cussing...

  7. Fusion ceramic materials and components

    International Nuclear Information System (INIS)

    Present-day approach for the radiation hardness assurance of components and materials for the International Thermonuclear Experimental Reactor ITER is based on extensive testing under representative conditions. Those conditions include radiation, temperature and vacuum and the possibility of in-situ monitoring of radiation-induced changes in characteristics of interest. The resistive bolometers are an example of an ITER component currently tested at SCK-CEN. Bolometers will be used for the plasma emission monitoring in high-radiation and high-temperature locations such as the divertor region. Previous tests with bolometers having gold strips on mica substrates were performed in the JMTR (Japan) and revealed problems of adhesion of the strips on the mica surface, which naturally has a very low roughness. A new type of the resistive bolometer based on platinum meander on alumina or aluminum-nitride (AlN) substrates have to be tested at a high neutron flux (0.01 dpa), high temperature (400 C) and in vacuum (10-3 mBar)- conditions appropriate for the ITER. Another illustration of on-going radiation testing for the ITER is the investigation of the Radiation-Induced Electrical Degradation (RIED). RIED is degradation of electrical insulation under the combined effect of radiation, temperature, vacuum and a strong electric field. It may be an issue to be dealt with in the design phase. Our objective is to develop instrumentation capabilities, which can provide in-situ data on the radiation hardness of materials and components intended for the use in the ITER. These capabilities will allow assessment of the performance parameters under conditions representative in terms of radiation load, temperature and vacuum, and will include on-line electric measurements

  8. Experimental qualification of nuclear components

    International Nuclear Information System (INIS)

    In the process of showing the adequacy of the seismic design of French PWR reactor, Fermat has repeatedly used dynamic testing on actual nuclear reactor components both on site and in manufacturing shops. The objective and results of a few representative examples of this on-site experimental verification are presented in this paper: the experimental dynamic analysis of a manipulator crane; the investigation of the seismic behaviour of fuel storage racks equipped with aseismic bearing devices. Difficulties to select satisfactory testing methods are also discussed for the particular case of the electrical cabinets. (author)

  9. Anthropological Component of Descartes’ Ontology

    Directory of Open Access Journals (Sweden)

    Anatolii M. Malivskyi

    2014-06-01

    Full Text Available The purpose of the article is to outline and comprehend the Descartes’ theory about anthropological component of ontology as the most important part of his philosophy. The accomplishment of this purpose covers the successive solution of the following tasks: 1 review of the research literature concerning the problem of human’s presence and the individual nature of truth; 2 emphasize the ambivalence of the basic intention of his legacy; 3 justify the thesis about constitutivity of human’s presence and comprehend passions as the form of disclosure of ontology’s anthropological component. Methodology. The use of the euristic potential of phenomenology, postpositivism and postmodernism makes it possible to emphasize the multiple-layer and multiple-meaning classical philosophy works, to comprehend the limitation and scarcity of the naïve-enlightening vision of human nature and to look for a new reception of European classics that provides the overcoming of established nihilism and pessimism concerning the interpretation of human nature. Scientific novelty. It is the first time that anthropological component of Descartes’ ontology became an object of particular attention. It previously lacked attention because of following main reasons: 1 traditional underestimating of the fact of Descartes’ legacy incompleteness as an unrealized anthropological project and 2 lack of proper attention to the individual nature of truth. The premise for its constructive overcoming is the attention to ambivalence of the basic intention and the significance of ethics in the philosopher’s legacy. His texts and research literature allow confirming the constitutive nature of human’s presence and passions as the key form of disclosure of the ontology anthropological component. Conclusions. The established tradition of interpretation the Descartes’ philosophizing nature as the filiation process of impersonal knowledge loses its cogency these days. The

  10. Carmen: Software Component Model Checker

    Czech Academy of Sciences Publication Activity Database

    Plšek, A.; Adámek, Jiří

    Berlin: Springer, 2008 - (Becker, S.; Plášil, F.; Reussner, R.), s. 71-85. (Lecture Notes in Computer Science. 5281). ISBN 978-3-540-87878-0. [QoSA 2008. International Conference on the Quality of Software Architectures /4./. Karlsruhe (DE), 14.10.2008-17.10.2008] Grant ostatní: GA ČR(CZ) GA201/08/0266; ANR/RNTL(FR) Flex-eWare; Belgian Science Policy(BE) Interuniversity Attraction Poles Programme Institutional research plan: CEZ:AV0Z10300504 Keywords : software components * behavior specification * model-checking Subject RIV: JC - Computer Hardware ; Software

  11. Bioactivity of Minor Milk Components

    DEFF Research Database (Denmark)

    Nguyen, Duc Ninh

    particular, 3-15% of very low birth weight preterm infants suffer from the most servere form of intestinal inflammation, known as necrotizing enterocolitis (NEC). This disease is incurable with a high mortality rate of 15-30%. Mother’s breast milk consists of different bioactive constituents, and is...... infant formula. Thereafter, bioactive milk components which were preserved in gently-processed infant formula were selected for further investigation of their immunomodulatory activity in cell and preterm pig models. We hope this project will contribute to the research on the development of new...

  12. Components of solar thermal systems

    OpenAIRE

    Mendes, J. Farinha; Carvalho, M. J.; Schossig, Peter

    2013-01-01

    The heat production sub-system is the part of the overall system which provides heat to a thermally driven air-conditioning system. With regards to the solar-driven equipment, the solar collector is the main component of the sub-system. A brief review on the present state-of-the-art with respect to performance characteristics and available certification schemes of solar collectors is given in the following chapter. Besides the solar collector field, the storage unit and the back-up heat sourc...

  13. Astrophysical components from Planck maps

    CERN Document Server

    Burigana, Carlo; Paoletti, Daniela; Mandolesi, Nazzareno; Natoli, Paolo

    2016-01-01

    The Planck Collaboration has recently released maps of the microwave sky in both temperature and polarization. Diffuse astrophysical components (including Galactic emissions, cosmic far infrared (IR) background, y-maps of the thermal Sunyaev-Zeldovich (SZ) effect) and catalogs of many thousands of Galactic and extragalactic radio and far-IR sources, and galaxy clusters detected through the SZ effect are the main astrophysical products of the mission. A concise overview of these results and of astrophysical studies based on Planck data is presented.

  14. The anatomic basis for the superior acetabular roof notch 'superior acetabular notch'

    International Nuclear Information System (INIS)

    Radiographic discontinuity of the acetabulum is a frequently encountered entity which has been described by various authors. We have been unable to find an explanation of the nature of this discontinuity in the literature. By correlating dried skeletal specimens with their radiographic appearances, we found the anatomic basis for this phenomenon was an accessory fossa in the apex of the acetabulum. (orig.)

  15. Spectral Components of SS 433

    CERN Document Server

    Gies, D R; Riddle, R L; Wang, Z; Wiita, P J; Wingert, D W

    2002-01-01

    We present results from new optical and UV spectroscopy of the unusual binary system SS 433, and we discuss the relationship of the particular spectral components we observe to the properties of the binary. (1) The continuum spectrum which we associate with flux from the super-Eddington accretion disk and the dense part of its wind. (2) H-alpha moving components which are formed far from the binary orbital plane in the relativistic jets. (3) H-alpha and He I "stationary" emission lines which we suggest are formed in the disk wind in a volume larger than the dimensions of the binary. (4) A weak "stationary" emission feature we identify as a C II 7231,7236 blend that attains maximum radial velocity at the orbital quadrature of disk recession. (5) Absorption and emission features from outflowing clumps in the disk wind (seen most clearly in an episode of blue-shifted Na I emission). (6) We found no clear evidence of the absorption line spectrum of the optical star, although we point out the presence of He I abso...

  16. Fractionalization of graphitic reactor components

    International Nuclear Information System (INIS)

    In Germany's research- and prototype reactors, some 590 t of graphite and carbonstone are in use, safe enclosure or due to decommissioning. Different concepts for their decommissioning are currently being discussed, all of which have to include any kind of fractionalization due to the fact that container dimensions do not refer to sizes of the above mentioned ceramic components. By means of parting techniques, activated/contaminated parts ought to be delaminated or parted in a way that a maximum ratio of container filling and the referring volume is reached. Thus, a maximum of final storage volume yield coinciding with a minimization of final disposal costs can be achieved. Fractionalization techniques will be developed or fitted with the aim of secondary waste minimization. Special focus ist put on the development of dust collection techniques in respect of emerging graphite dust out of the fractionalizating techniques. In 1995, a task group build up a concept regarding the dismantling of the Juelich AVR reactor to the green meadow [1]. One result of this study was the necessary amount containers for the final storage of all graphitic parts of the mentioned high-temperature reactor. The referred number was estimated to be 2511 MOSAIK II-type containers or 364 type VII-containers. To fill these containers, most of the graphitic components have to be parted. (orig.)

  17. Bioactive components in fish venoms.

    Science.gov (United States)

    Ziegman, Rebekah; Alewood, Paul

    2015-05-01

    Animal venoms are widely recognized excellent resources for the discovery of novel drug leads and physiological tools. Most are comprised of a large number of components, of which the enzymes, small peptides, and proteins are studied for their important bioactivities. However, in spite of there being over 2000 venomous fish species, piscine venoms have been relatively underrepresented in the literature thus far. Most studies have explored whole or partially fractioned venom, revealing broad pharmacology, which includes cardiovascular, neuromuscular, cytotoxic, inflammatory, and nociceptive activities. Several large proteinaceous toxins, such as stonustoxin, verrucotoxin, and Sp-CTx, have been isolated from scorpaenoid fish. These form pores in cell membranes, resulting in cell death and creating a cascade of reactions that result in many, but not all, of the physiological symptoms observed from envenomation. Additionally, Natterins, a novel family of toxins possessing kininogenase activity have been found in toadfish venom. A variety of smaller protein toxins, as well as a small number of peptides, enzymes, and non-proteinaceous molecules have also been isolated from a range of fish venoms, but most remain poorly characterized. Many other bioactive fish venom components remain to be discovered and investigated. These represent an untapped treasure of potentially useful molecules. PMID:25941767

  18. Preventive maintenance for mechanical components

    International Nuclear Information System (INIS)

    In nuclear power stations as in other industrial plants, there are active and passive components whose failure is permissible only in exceptional cases both from a safety and/or economic view. Failure in this context means loss of integrity of a supporting wall, insufficient function and/or unstoppable leakage. A systematic defect must be excluded as cause of failure; the consequences of failure must be manageable. During operation, measures must be taken to maintain the required quality and detect consequences of damage mechanisms at an early stage, prior to failure. This is achieved by preventive maintenance in accordance with the latest state of knowledge. To exclude systematic errors, the quality standard of components must be re-checked every once in a while as the effects of damage mechanisms and the state of knowledge are time-dependent parameters. This requires an integrated concept, e.g. for life and ageing management, in whose context a comprehensive knowledge base is developed and regularly updated. (orig.)

  19. GMES Space Component: Programme overview

    Science.gov (United States)

    Aschbacher, J.; Milagro-Perez, M. P.

    2012-04-01

    The European Union (EU) and the European Space Agency (ESA) have developed the Global Monitoring for Environment and Security (GMES) programme as Europe's answer to the vital need for joined-up data about our climate, environment and security. Through a unique combination of satellite, atmospheric and Earth-based monitoring systems, the initiative will provide new insight into the state of the land, sea and air, providing policymakers, scientists, businesses and the public with accurate and timely information. GMES capabilities include monitoring and forecasting of climatic change, flood risks, soil and coastal erosion, crop and fish resources, air pollution, greenhouse gases, iceberg distribution and snow cover, among others. To accomplish this, GMES has been divided into three main components: Space, In-situ and Services. The Space Component, led by ESA, comprises five types of new satellites called Sentinels that are being developed by ESA specifically to meet the needs of GMES, the first of which to be launched in 2013. These missions carry a range of technologies, such as radar and multi-spectral imaging instruments for land, ocean and atmospheric monitoring. In addition, access to data from the so-called Contributing Missions guarantees that European space infrastructure is fully used for GMES. An integrated Ground Segment ensures access to Sentinels and Contributing Missions data. The in-situ component, under the coordination of the European Environment Agency (EEA), is composed of atmospheric and Earth based monitoring systems, and based on established networks and programmes at European and international levels. The European Commission is in charge of implementing the services component of GMES and of leading GMES overall. GMES services, fed with data from the Space and In-situ components, will provide essential information in five main domains, atmosphere, ocean and land monitoring as well as emergency response and security. Climate change has been added

  20. Aspects for Run-time Component Integration

    DEFF Research Database (Denmark)

    Truyen, Eddy; Jørgensen, Bo Nørregaard; Joosen, Wouter;

    2000-01-01

    Component framework technology has become the cornerstone of building a family of systems and applications. A component framework defines a generic architecture into which specialized components can be plugged. As such, the component framework leverages the glue that connects the different insert...... dynamically integrate into the architecture of middleware systems new services that support non-functional aspects such as security, transactions, real-time.......Component framework technology has become the cornerstone of building a family of systems and applications. A component framework defines a generic architecture into which specialized components can be plugged. As such, the component framework leverages the glue that connects the different inserted...... components together. We have examined a middle ground between aspect-oriented programming and computational reflection that improves the dynamics of this gluing process such that interaction between components can be refined at run-time. In this paper, we show how we have used this middle ground to...

  1. Structural analysis of nuclear components

    International Nuclear Information System (INIS)

    THe report describes the activities accomplished in the project 'Structural Analysis Project of Nuclear Power Plant Components' during the years 1974-1982 in the Nuclear Engineering Laboratory at the Technical Research Centre of Finland. The objective of the project has been to develop Finnish expertise in structural mechanics related to nuclear engineering. The report describes the starting point of the research work, the organization of the project and the research activities on various subareas. Further the work done with computer codes is described and also the problems which the developed expertise has been applied to. Finally, the diploma works, publications and work reports, which are mainly in Finnish, are listed to give a view of the content of the project. (author)

  2. Parallel supercomputing with commodity components

    Energy Technology Data Exchange (ETDEWEB)

    Warren, M.S.; Goda, M.P. [Los Alamos National Lab., NM (United States); Becker, D.J. [Goddard Space Flight Center, Greenbelt, MD (United States)] [and others

    1997-09-01

    We have implemented a parallel computer architecture based entirely upon commodity personal computer components. Using 16 Intel Pentium Pro microprocessors and switched fast ethernet as a communication fabric, we have obtained sustained performance on scientific applications in excess of one Gigaflop. During one production astrophysics treecode simulation, we performed 1.2 x 10{sup 15} floating point operations (1.2 Petaflops) over a three week period, with one phase of that simulation running continuously for two weeks without interruption. We report on a variety of disk, memory and network benchmarks. We also present results from the NAS parallel benchmark suite, which indicate that this architecture is competitive with current commercial architectures. In addition, we describe some software written to support efficient message passing, as well as a Linux device driver interface to the Pentium hardware performance monitoring registers.

  3. Microelectromechanical components in electrical metrology

    CERN Document Server

    Manninen, Antti; Pesonen, Nadine; Oja, Aarne; Seppa, Heikki

    2007-01-01

    Microelectromechanical systems (MEMS) can offer a competitive alternative for conventional technology in electrical precision measurements. This article summarises recent work in development of MEMS solutions for electrical metrology. MEMS-based voltage references, RMS-to-DC converters, high frequency power sensors, and reference oscillators are discussed. The main principle of operation of the components is the balance between electrical forces and mechanical spring forces in micromachined silicon structures. In RMS sensors and RMS-to-DC converters, the quadratic voltage dependence of the force between plates of a moving-plate capacitor is utilised, and the operation of the MEMS voltage reference is based on the pull-in phenomenon of a moving-plate capacitor. Advantages of MEMS devices compared to more conventional solutions include small size, low power consumption, low price in mass production, and stability. The drift caused by electrostatic charging effects has turned out to be a major problem. This prob...

  4. Training of component reading skills.

    Science.gov (United States)

    Fiedorowicz, C A

    1986-01-01

    Fifteen reading-disabled boys, classified according to reading subskill deficits, formed three subgroups: Oral Reading, Associative, and Sequential. On the rationale that training procedures emphasizing accuracy and speed of response to letters, syllables, and words would improve reading skills, the children were trained daily for two and one-half months. Two schedules of testing and training allowed for an untrained control group and a follow-up group. The results indicated that the computer-assisted training procedures were not only effective in improving component reading skills, but in addition there was a transfer of training to achievement measures of reading word recognition. This study lends support to the hypothesis that training according to subgroup classification, using training procedures which incorporate an application of the automaticity theory and a combination of task-analytic and process-oriented models, is an effective training approach for reading-disabled children. PMID:24243467

  5. RCM and component evaluation logic

    International Nuclear Information System (INIS)

    This paper reports on the prevention maintenance program at Palo Verde Nuclear Generating Station (PVNGS), initially developed based on recommendations found in vendor technical manuals and accepted industry standards. The method was used until there was sufficient operating history to justify changes. The Reliability Centered Maintenance (RCM) project was started to provide another approach to the implementation of preventive maintenance. RCM evaluations were performed on nine systems. RCM was then suspended since it was found during implementation that additional documentation was necessary. RCM was selected as a preventive maintenance development process because it provides a documented analytical approach to establishing a preventive maintenance program. It is also being developed throughout the industry as a standard approach to preventive maintenance. PVNGS became interested in performing RCM analyses primarily to ensure that system and component reliability is maintained at the highest level possible and that hidden or rare failures are addressed by appropriate and effective maintenance. A secondary reason was to save maintenance expenditures

  6. Inelastic behavior of structural components

    Science.gov (United States)

    Hussain, N.; Khozeimeh, K.; Toridis, T. G.

    1980-01-01

    A more accurate procedure was developed for the determination of the inelastic behavior of structural components. The actual stress-strain curve for the mathematical of the structure was utilized to generate the force-deformation relationships for the structural elements, rather than using simplified models such as elastic-plastic, bilinear and trilinear approximations. relationships were generated for beam elements with various types of cross sections. In the generational of these curves, stress or load reversals, kinematic hardening and hysteretic behavior were taken into account. Intersections between loading and unloading branches were determined through an iterative process. Using the inelastic properties obtained, the plastic static response of some simple structural systems composed of beam elements was computed. Results were compared with known solutions, indicating a considerable improvement over response predictions obtained by means of simplified approximations used in previous investigations.

  7. Component codification and identification systems

    International Nuclear Information System (INIS)

    The lecture covers the codification in power stations during the erection phase and commercial operation phase. A diagram gives a survey. There are three basic-codifications for application; 1) Kraftwerk-Kennzeichen-System (KKS) for marking each component in orientated systems, for marking electrical orientated positions in cubicals, switch gears etc. and for marking rooms in buildings; 2) Ordnungssystem (OS) for cost calculation and ordering; 3) Unterlagenarten-Schluessel (UAS) for letters, reports etc. and for documentation. The OS is developed on the principle of cost account number and is therefore close to the organization of each supplier and his special form of design and constrution. KKS has only to mark hardware. Therefore all German owners, consultants, authorities and suppliers develop KKS together and conform to it in DIN 407119. (ORU)

  8. Components of Attention in Synesthesia

    DEFF Research Database (Denmark)

    Sørensen, Thomas Alrik; Nordfang, Maria; Pedersen, Michael Nygaard;

    2013-01-01

    synesthesia (Mattingley, 2009). Results from the present experiment show that synesthesia affects both speed of processing (C) and the number of objects that can be retained in visual short-term memory (K). Participants were faster at encoding characters that were colored congruently with their synesthesia......One of the most common forms of synesthesia is between colors and graphemes (Colizoli, Murre, & Rouw, 2012). Numerous studies have investigated different aspects of attention and synesthesia, e.g. effects of Stroop-like interference by colors that are incongruent with the synesthetic experience....... Here we attempt to isolate how specific components of attention are affected by grapheme-color synesthesia. Eight carefully screened healthy participants with synesthesia reported the letters in briefly presented, post-masked arrays of letters and digits. On half the trials, the letters and digits were...

  9. Components, Safety Interfaces, and Compositional Analysis

    OpenAIRE

    Elmqvist, Jonas

    2007-01-01

    Component-based software development has emerged as a promising approach for developing complex software systems by composing smaller independently developed components into larger component assemblies. This approach offers means to increase software reuse, achieve higher flexibility and shorter time-to-market by the use of off-the-shelf components (COTS). However, the use of COTS in safety-critical system is highly unexplored. This thesis addresses the problems appearing in component-based d...

  10. Library thermohydraulic components for training simulators

    International Nuclear Information System (INIS)

    The thermohydraulic components Library was modeled in MatLab/Simulink®. This library owns Pipe type components (pump, control valve and / or heaters), storage tanks (Open, Closed and Equilibrium Water Vapor-Air) and Heat Exchangers (Co-Current, Counter-Current and U-tubes). Each component can be attached to other components through the component library Header, in order to create a more complex thermal-hydraulic system which in turn can interact with other thermal-hydraulic systems. (author)

  11. A 10-year minimum follow-up of hydroxyapatite-coated threaded cups: clinical, radiographic and survivorship analyses with comparison to the literature.

    Science.gov (United States)

    Epinette, Jean-Alain; Manley, Michael T; D'Antonio, James A; Edidin, Avram A; Capello, William N

    2003-02-01

    We evaluated the clinical, radiographic, and survivorship outcomes in a series of 418 threaded hydroxyapatite-coated acetabular cups (Arc2f; Osteonics, Allendale, NJ) implanted in a consecutive series of 384 patients undergoing primary total hip arthroplasty. In all cases, the cup was screwed into the prepared acetabulum. Bone screws were used to provide secondary fixation. At a minimum 10-year follow-up, 304 cups were available for analysis. The cumulative survivorship (mechanical failure as endpoint) at that time was 99.43% +/- 0.0104. Two hundred seventy-six hips were available for full clinical and radiographic review at or after the tenth anniversary. No unstable implants were noted; all implant fixation interfaces were classified as "stable bone ingrown," and the cup migration rate was zero. Based on the survivorship achieved with this implant, our results compare favorably with survivorship reported for the best cemented and cementless acetabular implant designs. PMID:12629602

  12. Precision fiducialization of transport components

    International Nuclear Information System (INIS)

    The Final Focus Test Beam (FFTB) is a transport line designed to test both concept and advanced technology for application to future linear colliders. It is currently under construction at SLAC in the central beam line. Most of the quadrupoles of the FFTB have ab initio alignment tolerances of less than 30 microns, if the planned for beam based alignment tuning procedure is to converge. For such placement tolerances to have any meaning requires that the coordinates of the effective centers, seen by the beam particles, be tansferred to tooling (that can be reached by mechanical or optical alignment methods) located on the outside of the components to comparable or better values. We have constructed an apparatus that simultaneously locates to micron tolerances, the effective magnetic center of fussing lenses, as well as the electrical center of beam position monitors (BPM) imbedded therein, and once located, for transferring these coordinates to specially mounted tooling frames that supported the external retroreflectors used in a laser tracker based alignment of the beam line. Details of construction as well as experimental results from the method are presented

  13. Components development in the EU

    International Nuclear Information System (INIS)

    In the Euratom Sixth Framework Programme (FP6) an integrated project IP-EUROTRANS (transmutation) is ongoing. One of this project’s objectives is to develop and assess structural materials and heavy liquid metal (HLM) lead–lead-bismuth technologies for transmutation systems, where the HLM is both the spallation material and the core coolant. This involves specification and fabrication of reference materials, their characterisation in HLM and in representative conditions (with and without irradiation environment) in order to provide the data base needed for design purposes (e.g. fuel cladding, in-vessel components, primary vessel, instrumentation, target container, beam window), thermalhydraulics, measurement techniques, large scale integral tests and PTA studies for the MEGAPIE spallation target of FP5. In particular the ongoing R&D for the subcritical reactors XT-ADS, cooled by LBE, and EFIT, cooled by pure lead are: – To provide necessary information for designers, as concerns both T91 and 316L steels in contact with LBE and lead. This R&D is aimed to: • Determine the creep, low cycle fatigue, relaxation (fatigue and creep) fatigue behaviour of T91 and 316L in contact with lead and LBE, both qualitatively and quantitatively; • Characterize their fracture resistance, once again both qualitatively and quantitatively; • Constitute reliable data base over a wide temperature range, attaining 550°C; • Determine the fracture mechanisms of both ferritic–martensitic and austenitic materials in contact with HLMs

  14. Correlations among alfalfa yield components

    Directory of Open Access Journals (Sweden)

    Ilić Olivera

    2006-01-01

    Full Text Available Presented in this paper are the results of our study of correlations among yield components in ten alfalfa genotypes under open pollination (polycross conditions. The study was conducted between 2000 and 2002 at the Rimski Sancevi Experiment Field of the Institute of Field and Vegetable Crops in Novi Sad. Highly significant correlations were found between pod number per inflorescence and seed number per inflorescence (r= 0.645 as well as between seed number per pod and seed number per inflorescence (r= 0.685. Similarly, the correlation between inflorescence number per stem and seed yield was significant and positive (r= 0.589. Negative correlations existed between ovule number per ovary on the one hand and seed yield and inflorescence number per stem on the other (r= -0.617 and r= -0.598, respectively. The highest seed yield was achieved with the cultivar Europe (651.4 kg ha-1 and the lowest with the genotype Le-6 (426.25 kg ha-1. The difference was highly significant (CV= 14,93%.

  15. Bioactive Egg Components and Inflammation

    Directory of Open Access Journals (Sweden)

    Catherine J. Andersen

    2015-09-01

    Full Text Available Inflammation is a normal acute response of the immune system to pathogens and tissue injury. However, chronic inflammation is known to play a significant role in the pathophysiology of numerous chronic diseases, such as cardiovascular disease, type 2 diabetes mellitus, and cancer. Thus, the impact of dietary factors on inflammation may provide key insight into mitigating chronic disease risk. Eggs are recognized as a functional food that contain a variety of bioactive compounds that can influence pro- and anti-inflammatory pathways. Interestingly, the effects of egg consumption on inflammation varies across different populations, including those that are classified as healthy, overweight, metabolic syndrome, and type 2 diabetic. The following review will discuss the pro- and anti-inflammatory properties of egg components, with a focus on egg phospholipids, cholesterol, the carotenoids lutein and zeaxanthin, and bioactive proteins. The effects of egg consumption of inflammation across human populations will additionally be presented. Together, these findings have implications for population-specific dietary recommendations and chronic disease risk.

  16. Nonlinear principal component analysis of climate data

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, J.; Sengupta, S.

    1995-06-01

    This paper presents the details of the nonlinear principal component analysis of climate data. Topic discussed include: connection with principal component analysis; network architecture; analysis of the standard routine (PRINC); and results.

  17. Additive Manufacturing of Aerospace Propulsion Components

    Science.gov (United States)

    Misra, Ajay K.; Grady, Joseph E.; Carter, Robert

    2015-01-01

    The presentation will provide an overview of ongoing activities on additive manufacturing of aerospace propulsion components, which included rocket propulsion and gas turbine engines. Future opportunities on additive manufacturing of hybrid electric propulsion components will be discussed.

  18. Crosscap Numbers of Two-component Links

    OpenAIRE

    Zhang, Gengyu

    2006-01-01

    We define the crosscap number of a 2-component link as the minimum of the first Betti numbers of connected, non-orientable surfaces bounding the link. We discuss some properties of the crosscap numbers of 2-component links.

  19. CoC Awards by Program Component

    Data.gov (United States)

    Department of Housing and Urban Development — CoC Awards by Program Component reports provide snapshots of award data broken down by eligible program component types for the year selected. The reports, which...

  20. Improving component reuse in software development

    OpenAIRE

    Forsell, Marko

    2002-01-01

    This study concerns reuse in the software development process. The focus is in the reuse of components when creating new software. The aim is to improve current software processes to adapt them to the purposes of reuse. The specific research questions are: 1) What are the specific limitations for reuse in the current component-based software development methods? 2) How should reusable components be created and used in software development? 3) How should the components that are created be docu...

  1. Service component derivation and composition in Arctis

    OpenAIRE

    Xu, Fei

    2013-01-01

    Collaboration based development has its main focus on service level composition. Services are considered as reusable units and modeled as collaborations among roles performed by possibly distributed components. The problem addressed in this thesis is how components can be derived from the service models and how such components can be composed together in order to make a composite component and eventually a system. The purpose is to gain benefits such as flexibility in composition, allow compo...

  2. A QOS Ontology-Based Component Selection

    OpenAIRE

    Lamia Yessad; Zizette Boufaida

    2011-01-01

    In the component-based software development, the selection step is very important. It consists of searching and selecting appropriate software components from a set of candidate components in order to satisfy the developer-specific requirements. In the selection process, both functional and non-functional requirements are generally considered. In this paper, we focus only on the QoS, a subset of non-functional characteristics, in order to determine the best components for selection. The compo...

  3. Decomposing SAT Problems into Connected Components

    OpenAIRE

    Armin Biere; Carsten Sinz

    2006-01-01

    Many SAT instances can be decomposed into connected components either initially after preprocessing or during the solution phase when new unit conflict clauses are learned. This observation allows components to be solved individually. We present a technique to handle components within a GRASP like SAT solver without requiring much change to the solver. Results obtained when applying our implementation in the SAT solver COMPSAT to a number of realistic examples show that components really do ...

  4. Knee Arthroplasty: With or Without Patellar Component?

    Directory of Open Access Journals (Sweden)

    Árpád Sólyom

    2015-09-01

    Full Text Available Arthroplasty is used when there is irreversible damage to the articular cartilage of the knee. It involves implanting a bicompartimental (femoral and tibial components or a tricompartimental (femoral, tibial and patellar components prosthesis. It is a very invasive and costly operation, so our objective was to evaluate the necessity of the patellar component.

  5. Blind Detection of Independent Dynamic Components

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Larsen, Jan; Kolenda, Thomas

    2001-01-01

    In certain applications of independent component analysis (ICA) it is of interest to test hypotheses concerning the number of components or simply to test whether a given number of components is significant relative to a "white noise" null hypothesis. We estimate probabilities of such competing h...

  6. Characterisation of superconducting components using PSPICE

    NARCIS (Netherlands)

    Shevchenko, Oleg A.; Knoopers, Hennie G.; Kate, ten Herman H.J.

    1997-01-01

    A customer library of superconducting (SC) components for the PSPICE is under development in our group. The new library includes models of both low and high Tc superconductor based components. For large scale applications typical examples of simulated components are: a SC filament, composite wire an

  7. Two component theory and electron magnetic moment

    NARCIS (Netherlands)

    Veltman, M.J.G.

    1998-01-01

    The two-component formulation of quantum electrodynamics is studied. The relation with the usual Dirac formulation is exhibited, and the Feynman rules for the two-component form of the theory are presented in terms of familiar objects. The transformation from the Dirac theory to the two-component th

  8. Component failure data base of TRIGA reactors

    International Nuclear Information System (INIS)

    This compilation provides failure data such as first criticality, component type description (reactor component, population, cumulative calendar time, cumulative operating time, demands, failure mode, failures, failure rate, failure probability) and specific information on each type of component of TRIGA Mark-II reactors in Austria, Bangladesh, Germany, Finland, Indonesia, Italy, Indonesia, Slovenia and Romania. (nevyjel)

  9. Modelization of cooling system components

    International Nuclear Information System (INIS)

    In the site evaluation study for licensing a new nuclear power facility, the criteria involved could be grouped in health and safety, environment, socio-economics, engineering and cost-related. These encompass different aspects such as geology, seismology, cooling system requirements, weather conditions, flooding, population, and so on. The selection of the cooling system is function of different parameters as the gross electrical output, energy consumption, available area for cooling system components, environmental conditions, water consumption, and others. Moreover, in recent years, extreme environmental conditions have been experienced and stringent water availability limits have affected water use permits. Therefore, modifications or alternatives of current cooling system designs and operation are required as well as analyses of the different possibilities of cooling systems to optimize energy production taking into account water consumption among other important variables. There are two basic cooling system configurations: - Once-through or Open-cycle; - Recirculating or Closed-cycle. In a once-through cooling system (or open-cycle), water from an external water sources passes through the steam cycle condenser and is then returned to the source at a higher temperature with some level of contaminants. To minimize the thermal impact to the water source, a cooling tower may be added in a once-through system to allow air cooling of the water (with associated losses on site due to evaporation) prior to returning the water to its source. This system has a high thermal efficiency, and its operating and capital costs are very low. So, from an economical point of view, the open-cycle is preferred to closed-cycle system, especially if there are no water limitations or environmental restrictions. In a recirculating system (or closed-cycle), cooling water exits the condenser, goes through a fixed heat sink, and is then returned to the condenser. This configuration

  10. Novel Components for Neutron Counters

    International Nuclear Information System (INIS)

    Neutron counters for safeguards proposes have been developed during the last thirty years at the Joint Research Centre. The paper describes some of the latest developments and implementations in modern neutron counter. The design of a neutron counter is nowadays largely done by MCNP calculations. We have studied the behaviour of some components for a specific counter with respect to optimising the performance of the counter. This includes the moderator materials, thermal neutron absorbers, and 3-He detectors. Also the electronics for neutron counter has evolved over the years. Modern neutron counters require a large number of detectors and signal amplifiers to provide optimised parameters for the data interpretation. For this purpose we have developed a new pre-amplifier/amplifier/discriminator circuit which is both compact and inexpensive. The new circuit will be used in existing and future neutron counters. Concerning the treatment of the digital signal pulse train we intend to makes use of the latest advances in computer technology. A novel electronic system has been developed with a maximum of 128 input channels, which can cope with the high count rate of more than 1 million counts per second with zero dead-time. The Multi Input-Pulse Train Analysis (MI-PTA) system can be used with standard instruments, like Shift Register Analysers. However, it has been designed to perform a variety of pulse train analysis techniques itself, or in combination with a Personal Computer to which the system is connected via a High Speed USB2.0 connection. Pulse data can exchanged between the MI-PTA and PC at the rate of 480 Mb/s, allowing real time analysis on a PC and providing the basis for a Virtual Instrument approach: by modifying the software new instruments can be configured. The system consists of a number of base units, each with 8 TTL compatible inputs. Only one unit, configured as a Master, is connected to a PC. Up-to 15 Slave units can be connected to the Master via a

  11. MICROFLUIDIC COMPONENT CAPABLE OF SELF-SEALING

    DEFF Research Database (Denmark)

    2009-01-01

    A microfluidic component (100) for building a microfluidic system is provided. The microfluidic component (100) can be mounted on a microf luidic breadboard (202) in a manner that allows it to be connected to other microfluidic components (204, 206) without the requirement of additional devices....... The microfluidic component (100) comprises at least one flexible tube piece (102) for transporting a fluid. The microfluidic component (100) also comprises means for applying and maintaining pressure (104) between the flexible tube piece (102) and a tube piece (208, 210) housed in another microfluidic...

  12. VIRTUAL ELECTRONIC COMPONENTS OF THE ELECTRONIC EQUIPMENT

    Directory of Open Access Journals (Sweden)

    E. Lazarevich

    2013-01-01

    Full Text Available The article is present new idea of the creation, developments and improvements of the electronic equipment of complex systems by means of the virtual electronic components. The idea of the virtual electronic components is a presentation and perception of the creation and developments of the equipment on two forming: real – in the manner of standard marketed block of the intellectual property and image – in the manner of virtual component. The real component in most cases slows the development of the electronic equipment. The imaginary component is the «locomotive» of development of the electronic equipment. The Imaginary component contains the scientific has brushed against developer. The scientific has brushed against developer reveals of itself in the manner of virtual component on the modern level of the design rates of microelectronics.

  13. The artifacts of component-based development

    International Nuclear Information System (INIS)

    Component based development idea was floated in a conference name Mass Produced Software Components in 1968 (1). Since then engineering and scientific libraries are developed to reuse the previously developed functions. This concept is now widely used in SW development as component based development (CBD). Component-based software engineering (CBSE) is used to develop/ assemble software from existing components (2). Software developed using components is called component where (3). This paper presents different architectures of CBD such as Active X, common object request broker architecture (CORBA), remote method invocation (RMI) and simple object access protocol (SOAP). The overall objective of this paper is to support the practice of CBD by comparing its advantages and disadvantages. This paper also evaluates object oriented process model to adapt it for CBD. (author)

  14. Polarized CMB recovery with sparse component separation

    CERN Document Server

    Bobin, Jerome; Starck, Jean-Luc

    2015-01-01

    The polarization modes of the cosmological microwave background are an invaluable source of information for cosmology, and a unique window to probe the energy scale of inflation. Extracting such information from microwave surveys requires disentangling between foreground emissions and the cosmological signal, which boils down to solving a component separation problem. Component separation techniques have been widely studied for the recovery of CMB temperature anisotropies but quite rarely for the polarization modes. In this case, most component separation techniques make use of second-order statistics to discriminate between the various components. More recent methods, which rather emphasize on the sparsity of the components in the wavelet domain, have been shown to provide low-foreground, full-sky estimate of the CMB temperature anisotropies. Building on sparsity, the present paper introduces a new component separation technique dubbed PolGMCA (Polarized Generalized Morphological Component Analysis), which r...

  15. The artifacts of component-based development

    CERN Document Server

    Qureshi, M Rizwan Jameel

    2012-01-01

    Component based development idea was floated in a conference name "Mass Produced Software Components" in 1968 [1]. Since then engineering and scientific libraries are developed to reuse the previously developed functions. This concept is now widely used in SW development as component based development (CBD). Component-based software engineering (CBSE) is used to develop/ assemble software from existing components [2]. Software developed using components is called component ware [3]. This paper presents different architectures of CBD such as ActiveX, common object request broker architecture (CORBA), remote method invocation (RMI) and simple object access protocol (SOAP). The overall objective of this paper is to support the practice of CBD by comparing its advantages and disadvantages. This paper also evaluates object oriented process model to adapt it for CBD.

  16. SOFTWARE RELIABILITY MODEL FOR COMPONENT INTERACTION MODE

    Institute of Scientific and Technical Information of China (English)

    Wang Qiang; Lu Yang; Xu Zijun; Han Jianghong

    2011-01-01

    With the rapid progress of component technology,the software development methodology of gathering a large number of components for designing complex software systems has matured.But,how to assess the application reliability accurately with the information of system architecture and the components reliabilities together has become a knotty problem.In this paper,the defects in formal description of software architecture and the limitations in existed model assumptions are both analyzed.Moreover,a new software reliability model called Component Interaction Mode (CIM) is proposed.With this model,the problem for existed component-based software reliability analysis models that cannot deal with the cases of component interaction with non-failure independent and non-random control transition is resolved.At last,the practice examples are presented to illustrate the effectiveness of this model

  17. Synthesis from Recursive-Components Libraries

    CERN Document Server

    Lustig, Yoad; 10.4204/EPTCS.54.1

    2011-01-01

    Synthesis is the automatic construction of a system from its specification. In classical synthesis algorithms it is always assumed that the system is "constructed from scratch" rather than composed from reusable components. This, of course, rarely happens in real life. In real life, almost every non-trivial commercial software system relies heavily on using libraries of reusable components. Furthermore, other contexts, such as web-service orchestration, can be modeled as synthesis of a system from a library of components. In 2009 we introduced LTL synthesis from libraries of reusable components. Here, we extend the work and study synthesis from component libraries with "call and return"' control flow structure. Such control-flow structure is very common in software systems. We define the problem of Nested-Words Temporal Logic (NWTL) synthesis from recursive component libraries, where NWTL is a specification formalism, richer than LTL, that is suitable for "call and return" computations. We solve the problem, ...

  18. Highly polarized components of integrated pulse profiles

    CERN Document Server

    Wang, P F

    2016-01-01

    Highly polarized components of pulse profiles are investigated by analyzing observational data and simulating the emission processes. The highly polarized components appear at the leading or trailing part of a pulse profile, which preferably have a flat spectrum and a flat polarization angle curve compared with the low polarized components. By considering the emission processes and propagation effects, we simulate the distributions of wave modes and fractional linear polarization within the entire pulsar emission beam. We show that the highly polarized components can appear at the leading, central, and/or trailing parts of pulse profiles in the models, depending on pulsar geometry. The depolarization is caused by orthogonal modes or scattering. When a sight line cuts across pulsar emission beam with a small impact angle, the detected highly polarized component will be of the O mode, and have a flat polarization angle curve and/or a flat spectrum as observed. Otherwise, the highly polarized component will be o...

  19. Programming language abstractions for extensible software components

    OpenAIRE

    Zenger, Matthias; Odersky, Martin

    2005-01-01

    With the growing demand for software systems that can cope with an increasing range of information processing tasks, the reuse of code from existing systems is essential to reduce the production costs of systems as well as the time to manufacture new software applications. For this reason, component-based software development techniques gain increasing attention in industry and research. Component technology is driven by the promise of building software by composing off-the-shelf components p...

  20. Projected principal component analysis in factor models

    OpenAIRE

    Fan, Jianqing; Liao, Yuan; Wang, Weichen

    2014-01-01

    This paper introduces a Projected Principal Component Analysis (Projected-PCA), which employees principal component analysis to the projected (smoothed) data matrix onto a given linear space spanned by covariates. When it applies to high-dimensional factor analysis, the projection removes noise components. We show that the unobserved latent factors can be more accurately estimated than the conventional PCA if the projection is genuine, or more precisely, when the factor loading matrices are r...