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Sample records for cementless acetabular components

  1. The use of cementless acetabular component in revision surgery without pelvic discontinuity.

    Science.gov (United States)

    Cherubino, Paolo; D'Angelo, Fabio; Surace, Michele Francesco; Murena, Luigi; Vulcano, Ettore

    2010-10-01

    Reconstruction of the failed acetabular component in total hip arthroplasty (THA) can be challenging. Although there are multiple reconstructive options available, a cementless acetabular component inserted with screws has been shown to have good intermediate-term results and is the reconstructive method of choice for the majority of acetabular revisions This reconstruction is feasible provided at least 50% of the implant contacts host bone. When such contact is not possible, and there is adequate medial and peripheral bone, techniques using alternative uncemented implants can be used for acetabular reconstruction. An uncemented cup can be placed at a "high hip center." Alternatively, the acetabular cavity can be progressively reamed to accommodate extra-large cups. Oblong cups, which take advantage of the oval-shaped cavity resulting from many failed acetabular components, can also be used. The success of these cementless techniques depends on the degree and location of bone loss. The correct indication to revision and the choice of the correct implant is the keystone for the success of this type of surgery and follows an accurate preoperative planning in order to understand the specific pathologic scenario. The aim of this paper is to review some technical options for the revision of the acetabular component also taking into account our personal experiences and series. PMID:21082580

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

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    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. 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 yea...

  4. Radiographic and clinical analysis of cementless acetabular fixation in total hip arthroplasty

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hui; PEI Fu-xing; YANG Jing; SHEN Bin; SHI Rui

    2005-01-01

    Objective: To investigate the factors affecting the fixation, loosening and therapeutic effect of cementless acetabular prosthesis through following up the patients with total hip arthroplasty clinically and radiographically.Methods: From February 1998 to May 1999, 139 patients (148 hips) underwent total hip arthroplasty with cementless acetabular prosthesis in our department. In this study, the clinical therapeutic effect and the anteroposterior radiographs of the pelvis and anteroposterior and lateral radiographs of the hips of 109 patients (116 hips) made before operation, at 1 week, 3, 6, and 12 months after operation and annually thereafter were analyzed retrospectively. The clinical therapeutic effects were evaluated with Harris hip score. Radiographs were used to observe the position of prostheses and the bone changes around the implant, and to measure the wearing speed and direction of the acetabular cup. All evaluations were made by an independent examiner who did not participate in the operation. The patients were followed up for 5-6 years.Results: The mean Harris score was 44 points (range, 10-70 points) before operation, but it increased to 92.4 points (range, 80-100 points) at the latest review after operation, which was significantly higher than that before operation (P<0.05). No acetabular component was revised because of infection or aseptic loosening. And no acetabular component migrated. There was no revision of fixed acetabular component because of pelvic osteolysis secondary to polyethylene wear. The mean linear wear rate was 0.15 mm per year. All the acetabular prostheses were classified as stable on the radiographs.Conclusions: In terms of fixation, total hip arthroplasty with cementless acetabular components was successful. Although there is no aseptic loosening and a low incidence of osteolysis at the latest follow-up evaluation, polyethylene wear cannot be avoided and can lead to expansile osteolysis near the cups. This kind of osteolysis

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

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    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

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

    Institute of Scientific and Technical Information of China (English)

    Ashok S Gavaskar; Naveen Chowdary Tummala

    2012-01-01

    Total hip arthroplasty (THA) for an untreated acetabular fracture is technically challenging and the long-term result is not so favorable.A 45-year-old female patient with untreated column and comminuted posterior wall fracture of the acetabulum was treated in our institution by reconstruction of the posterior wall using iliac strut autograft and plate stabilization of the posterior column 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 evaluation showed well integrated components and bone grafts.No evidence of aseptic loosening or osteolysis was found.This report aims to emphasize that bony acetabular reconstruction allows the use of primary hip components,which improves prosthesis longevity and preserves bone stock for a future revision.

  7. The influence of acetabular inclination angle on the penetration of polyethylene and migration of the acetabular component: a prospective, radiostereometric study on cemented acetabular components.

    Science.gov (United States)

    Kadar, T; Furnes, O; Aamodt, A; Indrekvam, K; Havelin, L I; Haugan, K; Espehaug, B; Hallan, G

    2012-03-01

    In this prospective study we studied the effect of the inclination angle of the acetabular component on polyethylene wear and component migration in cemented acetabular sockets using radiostereometric analysis. A total of 120 patients received either a cemented Reflection All-Poly ultra-high-molecular-weight polyethylene or a cemented Reflection All-Poly highly cross-linked polyethylene acetabular component, combined with either cobalt-chrome or Oxinium femoral heads. Femoral head penetration and migration of the acetabular component were assessed with repeated radiostereometric analysis for two years. The inclination angle was measured on a standard post-operative anteroposterior pelvic radiograph. Linear regression analysis was used to determine the relationship between the inclination angle and femoral head penetration and migration of the acetabular component. We found no relationship between the inclination angle and penetration of the femoral head at two years' follow-up (p = 0.9). Similarly, our data failed to reveal any statistically significant correlation between inclination angle and migration of these cemented acetabular components (p = 0.07 to p = 0.9).

  8. 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.

  9. Is there evidence for accelerated polyethylene wear in uncemented compared to cemented acetabular components? A systematic review of the literature

    NARCIS (Netherlands)

    van der Veen, Hugo; van Jonbergen, H.P.W.; Poolman, R.W.; Bulstra, S.K.; van Raay, J.J.A.M.

    2013-01-01

    Joint arthroplasty registries show an increased rate of aseptic loosening in uncemented acetabular components as compared to cemented acetabular components. Since loosening is associated with particulate wear debris, we postulated that uncemented acetabular components demonstrate a higher polyethyle

  10. 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.

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

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    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

  12. 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

  13. 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

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

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    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.

  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. Femoral component revision using extensively porous-coated cementless stem

    Institute of Scientific and Technical Information of China (English)

    WU Li-dong; XIONG Yan; YAN Shi-gui; YANG Quan-sen; DAI Xue-song

    2005-01-01

    Objective: To evaluate the clinical and radiographic results of extensively porous-coated femoral stem in revision of total hip arthroplasty (THA).Methods: From January 1999 to December 2003,fifteen hips of fifteen cases received revision of THA with extensively porous-coated femoral stem. There were six males and nine females. The average age was 66 years (ranging 58-82 years). The reason for the revision was aseptic loosening in 10 cases, septic loosening in 2, femoral shaft fracture around loose implant in 2, and femoral revision for malposition of the femoral component in 1. All the patients were clinically evaluated using Harris hip score and radiographically evaluated both preoperatively and postoperatively at regular follow-up intervals.Results: No patients were lost for follow-up. The average length of follow-up was 2.3 years (range, 1-5years). The average preoperative Harris hip score was 42points, which was improved to 89 points at latest follow-up.The latest follow-up showed that bone in-growth occurred in fourteen stems and solid fibrous fixation in one.Complications consisted of femoral shaft fracture in two cases (1 undisplaced distal femur fracture and 1 cortical perforation at the tip of the prosthesis), and postoperative dislocation in one. There was no mechanical failure of the stem in this study.Conclusions: Satisfactory results of short-term clinical and radiographic follow-up have been achieved in using extensively porous-coated femoral stem for revision of THA. It should be noticed that the straight, 203 mm stem should be used with caution in short people.

  17. The concentric all-polyethylene Exeter acetabular component in primary total hip replacement.

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    Veitch, S W; Whitehouse, S L; Howell, J R; Hubble, M J W; Gie, G A; Timperley, A J

    2010-10-01

    We report the outcome of the flangeless, cemented all-polyethylene Exeter acetabular component at a mean of 14.6 years (10 to 17) after operation. Of the 263 hips in 243 patients, 122 prostheses are still in situ; 112 patients (119 hips) have died, 18 hips have been revised, and three patients (four hips) were lost to follow-up. Radiographs at the final review were available for 110 of the 122 surviving hips. There were acetabular radiolucent lines in 54 hips (49%). Two acetabular components had migrated but neither patient required revision. The Kaplan-Meier survivorship at 15 years with 61 hips at risk with revision for any cause as the endpoint was 89.9% (95% confidence interval (CI) 84.6 to 95.2) and for aseptic loosening of the acetabular component or lysis 91.7% (95% CI 86.6 to 96.8). In 210 hips with a diagnosis of primary osteoarthritis, survivorship with revision for any cause as the endpoint was 93.2% (95% CI 88.1 to 98.3), and for aseptic loosening of the acetabular component 95.0% (95% CI 90.3 to 99.7). The cemented all-polyethylene Exeter acetabular component has an excellent long-term survivorship.

  18. Pelvic Discontinuity Caused by Acetabular Overreaming during Primary Total Hip Arthroplasty

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    Iori Takigami

    2011-01-01

    Full Text Available Intraoperative acetabular fracture is a rare complication of primary total hip arthroplasty (THA, typically occurring during impaction of the cementless acetabular component. Here we report an unusual case of pelvic discontinuity caused by overreaming of the acetabulum during primary THA. Restoration of posterior columnar continuity was achieved with an autologous fibular graft and a reconstruction plate. Wall defects and cavitary defects were reconstructed with metal mesh and femoral head allograft, followed by placement and fixation of a Kerboull-type acetabular reinforcement device. Previous reports of acetabular fracture during THA have indicated that it has a relatively good prognosis without extensive treatment. However, to our knowledge, there has been no report of pelvic discontinuity necessitating acetabular reconstruction surgery as an intraoperative complication of primary THA.

  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. 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...

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

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    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

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    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. 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

    Worldwide use of cementless fixation for total hip arthroplasty (THA) is on the rise despite some evidence from the world's registries suggesting inferior survivorship compared with cemented techniques. The patterns of bone loss associated with failed cementless and cemented THAs may prejudice...

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

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    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.

  6. Polyethylene sterilized without irradiation in a polished uncemented acetabular component-a clinical and radiographic analysis.

    Science.gov (United States)

    Crockarell, John R

    2008-09-01

    Clinical and radiographic analysis of the Reflection uncemented acetabular component was performed. Features of this component include a polished inner shell and ethylene oxide sterilization. Clinical information was available for 158 hips (mean, 4.6 years follow-up). A total of 19 hips have undergone or were recommended revision, 8 for aseptic loosening or wear (5%). Wear analysis was performed for 38 hips with more than 5 years of follow-up (mean, 6.7 years). Osteolysis was present in 20 of these patients. Penetration rate averaged 0.15 mm/y. Patients with uncemented femoral fixation (vs cemented) had a significantly higher penetration rate. Increased volumetric wear was seen with uncemented femoral fixation, thin liners, and ceramic heads. This component demonstrated relatively high penetration and osteolysis rates. Continued surveillance is recommended, particularly for active patients with thin liners. PMID:18534518

  7. 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

  8. Late fiber metal shedding of the first and second-generation Harris Galante acetabular component. A report of 5 cases.

    Science.gov (United States)

    Mayman, David J; González Della Valle, Alejandro; Lambert, Edward; Anderson, John; Wright, Timothy; Nestor, Bryan; Sculco, Thomas P; Salvati, Eduardo A

    2007-06-01

    Five patients presented with fiber metal mesh shedding of a Harris Galante II acetabular cup detected between 11 and 15 years after implantation. All patients presented with hip pain and 4 demonstrated gross acetabular loosening and fiber metal separation on preoperative radiographs. The remaining patient underwent revision surgery because of a liner dislodgment and had a radiographically well fixed shell. Loosening and fiber metal separation were detected intraoperatively. Scanning electron microscopy of the retrieved shells demonstrated isolated diffusion bonding marks in the areas where the mesh separated from the substrate and no evidence of corrosion. Progressive osteolysis in the iliac bone was evident in 4 of our cases. Progressive iliac osteolysis may lead to loss of bone support in well-fixed cups and excessive stresses transferred to the interface between the fiber metal mesh and the titanium substrate leading to the separation of the 2 layers. Fiber metal separation may contribute to long-term loosening in the Harris Galante acetabular component.

  9. 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...

  10. 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.

  11. 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 ...

  12. 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

  13. Osteocondroma acetabular Acetabular osteochondroma

    Directory of Open Access Journals (Sweden)

    Reynaldo Jesus Garcia

    2005-01-01

    Full Text Available Apresentamos o relato de um caso de osteocondroma solitário acetabular, tumor ósseo comum em diversas regiões do esqueleto porém raro nesta localização. O tratamento realizado foi a ressecção do tumor por uma via posterior ao quadril e o paciente evoluiu com resolução do quadro clínico.This is a case report of a patient with a intra-articular hip osteochondroma, an extremely rare location for this kind of lesion. The patient was treated with resection of the lesion and presented a very good evolution with total recovery of the hip movements.

  14. Influence of pelvic position on radiographic measurements of the prosthetic acetabular component; An experimental study on a pelvic model

    Energy Technology Data Exchange (ETDEWEB)

    Thoren, B.; Sahlstedt, B. (Uppsala Univ. (Sweden). Dept. of Orthopaedic Surgery Uppsala Univ. (Sweden). Dept. of Diagnostic Radiology)

    1990-03-01

    A change in the position of a prosthetic acetabular component between two different radiographic examinations indicates loosening, and may be observed as tilting or migration of the socket. To determine the apparent changes in socket position caused by improper positioning of the pelvis, a full-scale model of a pelvis with attached prosthetic sockets was examined radiographically in different positions. The projected alignment of the Charnley socket indicator wire against the inter-tuberosity line was markedly influenced by the positioning of the pelvis. An alternative way of measuring the alignment is to use the long axis of the projected ellipse of the outer circumferential groove in the socket polyethylene. The thus defined socket alignment was not influenced by the positioning of the pelvis within the investigated range. No apparent socket migration was recorded within the range of pelvic rotation and inclination studied. (orig.).

  15. Effects of femoral component material properties on cementless fixation in total hip arthroplasty. A comparison study between carbon composite, titanium alloy, and stainless steel.

    Science.gov (United States)

    Otani, T; Whiteside, L A; White, S E; McCarthy, D S

    1993-02-01

    Carbon-fiber-reinforced-carbon composite material is an attractive implant material because its modulus of elasticity can be made similar to that of cortical bone. This study investigated the effect of femoral prosthesis elastic modulus on cementless implant fixation. Distal, as well as proximal, relative micromovements between implant and bone were measured in two testing protocols (axial-load and torsional-load), comparing identically shaped carbon composite (modulus of elasticity = 18.6 GPa), Ti6Al4V (100 GPa), and 630 stainless steel (200 GPa) prostheses. In the axial-load test, proximal mediolateral micromotions were significantly larger in the flexible composite stem than in the two metals. In the torsional-load test, rotational micromotions and "slop" displacements in the flexible stem were significantly larger proximally and significantly smaller distally than in the two metals. While these results suggest that proximal stress transfer may be improved by a flexible stem, they raise the possibility of increased proximal micromotion, and suggest that improved proximal fixation may be necessary to achieve clinical success with flexible composite femoral components.

  16. 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.

  17. 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...

  18. 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

  19. Retroperitoneal hematoma with bone resorption around the acetabular component after total hip arthroplasty: a case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Uchida Kenzo

    2012-09-01

    Full Text Available Abstract Introduction Vascular complications related to cup-fixating screws penetrating the medial acetabular wall during total hip arthroplasty are not uncommon but rarely are associated with serious adverse events in the late post-operative period. Case presentation We present the case of a 77-year-old Japanese woman who developed progressive extensive bone resorption and large hematoma in the acetabulum 13 years after total hip arthroplasty. On admission to our hospital, she was on oral warfarin (1.5mg/day for atrial fibrillation. About 5 months after the initiation of anticoagulant therapy, she suffered a major fall followed by massive subcutaneous and pelvic girdle bleeding, predominantly on the medial side of the right thigh, but a fracture or damage of total hip arthroplasty was not evident on an emergency orthopedic evaluation. One year after the accident, a routine follow-up examination showed an asymptomatic osteolytic lesion in the acetabulum on the right pelvis, and 2 years later our patient noticed progressive pain in her right hip during walking. A large osteolytic lesion was noted in the right acetabulum on a plain radiograph. On high-resolution computed tomography and magnetic resonance imaging, a huge granulomatous lesion in the acetabulum was suggestive of chronic hematoma in intrapelvic and extrapelvic gluteal regions. A closer computed tomography examination showed that one of the screws used for fixation of the acetabular component in the total hip arthroplasty had penetrated the acetabular bone and had reached the pelvic cavity. Surgery was performed in a single session by means of two approaches: anterior midline transperitoneal address to resect the low-density mass lesion followed by posterolateral acetabular implant re-settlement. Conclusions Though rare, total hip arthroplasty-related late vascular complications could be serious and potentially affect the limb and quality of life.

  20. 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

  1. Evaluation of the wear performance of a polycarbonate-urethane acetabular component in a hip joint simulator and comparison with UHMWPE and cross-linked UHMWPE.

    Science.gov (United States)

    St John, Kenneth; Gupta, Minakshi

    2012-07-01

    Acetabular hip joint components manufactured from gamma-sterilized ultra high molecular weight polyethylene (UHMWPE), gamma cross-linked UHMWPE, or polycarbonate-urethane (PCU) polymers were evaluated in a hip joint simulator, using cobalt alloy femoral components, for at least 5 million cycles. The volume of material losses due to wear was calculated for each type of sample, based upon mass loss measurements, every 500,000 cycles. The loss of material for the conventional UHMWPE was much higher than for the cross-linked UHMWPE, showing about a 70% reduction in wear due to cross-linking. The material loss for the PCU samples appears to have been at least 24% lower than for the cross-linked UHMWPE. Based upon these results, the PCU material seems to have potential for use as an alternative bearing material to UHMWPE for total hip replacement surgeries.

  2. Primary total hip arthroplasty for acetabular fracture

    Institute of Scientific and Technical Information of China (English)

    WANG Zi-ming; SUN Hong-zhen; WANG Ai-min; DU Quan-yin; WU Siyu; ZHAO Yu-feng; TANG Ying

    2006-01-01

    Objective: To explore the operative indications and operative methods of primary total hip arthroplasty for acetabular fracture and to observe the clinical curative effect.Methods: We retrospectively summarized and analyzed the traumatic conditions, fracture types, complications,operative time, operative techniques, and short-term curative effect of 11 patients( 10 males and 1 female, with a mean age of 42. 4 years ) with acetabular fracture who underwent primary total hip arthroplasty.Results: The patients were followed up for 6-45 months ( mean = 28 months). Their average Harris score of postoperative hip joint was 78.Conclusion: Under strict mastery of indications,patients with acetabular fracture may undergo primary total hip arthroplasty, but stable acetabular components should be made.

  3. 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.

  4. Design optimization of cementless metal-backed cup prostheses using the concept of functionally graded material

    Energy Technology Data Exchange (ETDEWEB)

    Hedia, H S; El-Midany, T T; Shabara, M A N; Fouda, N [Production Engineering and M/C Design Department, Faculty of Engineering, Mansoura University, Mansoura (Egypt)

    2006-09-15

    Metal backing has been widely used in acetabular cup design. A stiff backing for a polyethylene liner was initially believed to be mechanically favourable. Yet, recent studies of the load transfer around acetabular cups have shown that a stiff backing causes two problems. It generates higher stress peaks around the acetabular rim than those caused by full polyethylene cups and reduces the stresses transferred to the dome of the acetabulum causing stress shielding. The aim of this study is to overcome these two problems by improving the design of cementless metal-backed acetabular cups using the two-dimensional functionally graded material (FGM) concept through finite-element analysis and optimization techniques. It is found that the optimal 2D FGM model must have three bioactive materials of hydroxyapatite, Bioglass and collagen. This optimal material reduces the stress shielding at the dome of the acetabulum by 40% and 37% compared with stainless steel and titanium metal backing shells, respectively. In addition, using the 2D FGM model reduces the maximum interface shear stress in the bone by 31% compared to the titanium metal backing shell.

  5. 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)...

  6. 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.)

  7. 全髋关节置换术中髋臼假体定位的研究进展%Progress of research on the orientation of the acetabular component in total hip arthroplasty

    Institute of Scientific and Technical Information of China (English)

    胡海贝; 周建生

    2016-01-01

    目前全髋关节置换术已成为治疗终末期髋关节疾病的有效手段,由于髋臼侧结构的特殊性,髋臼杯位置的定位方法尚有争议。髋臼假体定位方法主要有根据术前、术中影像学资料定位,根据髋臼局部解剖特征和(或)结合机械设备定位等,本文就髋臼假体位置定位的研究进展作一综述。%At present,total hip arthroplasty has become an effective method for the treatment of end-stage hip disease.Because of the special structure of the acetabulum,the methods for determining the position of the ace-tabular cup are disputed.The orientation methods of the acetabular components are mainly determined by the preop-erative and intraoperative imaging data,local anatomical characteristics of the acetabulum in combination with the mechanical equipment.This paper reviews the progress in research on orientating acetabular prosthesis position.

  8. 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 ...

  9. Modeling and finite element analysis of a new acetabular revision component with three wings%三翼髋臼假体有限元模型的建立及其力学分析

    Institute of Scientific and Technical Information of China (English)

    马文辉; 张学敏; 王继芳; 时述山

    2010-01-01

    Objective To analyze and evaluate a new acetabular revision component with three wings. Methods The finite-element models of a new acetabular component and acetabulum with bone loss were established to calculate the interface stresses during a normal gait cycle with use of the finite-element formulations. Results The finite-element analysis demonstrated that stress and strain at the interfaces of bone-shell and metal-polyethylene liner had the same direction of change but no remarkable difference between them. In the study, the result indicated increased contact stresses with an increased joint load and orientation. The peak stress was tested at the second stage of gait cycle. The stress of wings increased gradually from rim to root. Its peak stress that was significantly lower than yield force of the Co-Cr alloy was at the joint between the wing and the shell. The stress of graft had the same change rule as the joint force. The part of graft near to acetabular component was subjected to higher stress conditions. Conclusion The hip forces can transfer from acetabular component and implant to acetabulum. The result of the finite-element analysis underlined the importance of wings of the new acetabular component. The wing can help to improve the antitorsion ability of acetabular component and to minimize its aseptic loosening rate. Therefore, based on results of this study and clinical application, the acetabular component with wings is known a viable means for acetabular revision in the presence of bone loss. But further research is needed as to this acetabular component.%目的 对于一种临床上用于髋臼骨缺损的新型三翼髋臼翻修假体的设计进行有限元分析及力学评价.方法 建立三翼翻修假体及缺损髋臼的有限元模型,应用有限元分析公式计算在髋臼骨缺损翻修后,翻修假体在正常步态周期内的应力变化规律.结果 研究证实在正常步态周期内,三翼髋臼假体金属壳两侧界面的

  10. 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.

  11. Bone remodeling around cementless tantalum cups

    NARCIS (Netherlands)

    Grillo, J. -C.; Flecher, X.; Bouvenot, J.; Argenson, J. -N.

    2008-01-01

    Purpose of the study.-Most studies have reported a significant decrease in periacetabular bone stock one year after implantation of a cementless cup. The purpose of this work was to study the bone-implant interface of the tantalum cup using plain X-rays and dual-energy X-ray absorptiometry (DEXA). M

  12. Operative strategy of acetabular fractures

    Institute of Scientific and Technical Information of China (English)

    WANG Yan; TANG Pei-fu; HUANG Peng

    2006-01-01

    Anatomic structure of acetabular fractures are complex and operative exposure and fixation are extremely difficult.For those obviously displaced acetabular fractures, close reduction is doomed to cause deformative healing. Open reduction with internal fixation (ORIF) not only results in anatomic reduction, but also brings complications. No matter which method will be adopted, traumatic arthritis or avascular necrosis of femoral head might occur. In order to treat acetabular fractures more effectively, orthopedic surgeons should be required to fully master the acetabular anatomy, biomechanics, classification and the necessary knowledge for complication prevention.

  13. Protrusio of a ceramic femoral head through the acetabular metallic shell, extensive metallosis and 'bubble sign'.

    Science.gov (United States)

    Malizos, Konstantinos; Roidis, Nikolaos T; Poultsides, Lazaros; Basdekis, George; Moraitis, Theofanis; Xenakis, Theodoros

    2009-02-01

    A 24-year-old patient with a history of juvenile rheumatoid arthritis underwent a primary cementless left total hip arthroplasty (THA). The original THA consisted of an Optifix 54 cup with a 3-mm thick polyethylene liner, an Optifix size 4 stem (Smith & Nephew Richards, Memphis, Tennessee) and a Biolox aluminum 32-mm femoral head. Fourteen years later, radiographs demonstrated extensive wear of the polyethylene liner resulting in direct articulation and abrasion wear of the ceramic femoral head on the cup and a bubble sign. This article presents a case of a catastrophic failure of a ceramic/polyethylene bearing with destruction of the polyethylene liner and the metallic shell and protrusio of the nonfractured ceramic head through the metallic shell. To our knowledge this is the first description of extensive metallosis and subsequent radiograph bubble sign not presenting as a result of wear of a metal-on-metal articulation. At the time of revision surgery-Hydrocel TNT Monoblock 58 cup (Zimmer, Warsaw, Indiana), Wagner 265/14 stem (Zimmer), and a Co/Cr 28-mm head-copious metallic debris was seen both macroscopically and histologically, with the ceramic head protruding behind the metallic shell. Multiple factors may have been responsible for this failure including a thin polyethylene shell, a suboptimal locking mechanism, gamma in air sterilization for polyethylene, multiple screw-holes that reduce the contact surface between shell and polyethylene, the rough surface on the inside of the shell and non-articular wear at the metal polyethylene interface within the acetabular component and the high demands of this active young patient. PMID:19301791

  14. 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

  15. 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.

  16. 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...

  17. 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.

  18. Feasibility and and accuracy of image based surgical navigation system in setting the orientation of acetabular component%计算机导航中髋臼杯角度设定的可行方法及其精确性验证

    Institute of Scientific and Technical Information of China (English)

    马若凡; 许杰; 董彬; 丁悦; 李登; 刘尚礼

    2009-01-01

    目的:分析计算机导航对人工髋关节臼杯置入角度设定的可行性方法并评估其精确性.方法:将CT扫描资料进行计算机三维影像重建,并进行虚拟像与真实骨盆间匹配对应,在虚拟空间中,确立骨盆冠状、矢状、水平及前倾平面,并以此为基准进行计算机导航辅助下多角度设定的臼杯置入,由角度测量仪对臼杯置入角度的精确性进行测量验证.结果:导航辅助臼杯外展角置入,设定值与真实值间差异(0.46±1,53)°;对于臼杯前倾角,差异(0.79±1.37)°.两次独立操作所得结果作配对t检验,臼杯外展及前倾角均无显著性差异(t外展=1.15,t前倾=1.14,P>0.05).结论:研制的基于CT影像资料的计算机导航可有效的设定臼杯假体置入角度,精确地引导臼杯置入.%Objective: To evaluate the feasibility of image based surgical navigation system in setting the orientation of acetabular component and improving the accuracy of it in total hip arthroplasty. Methods: CT scan data of one cadaver without deformity were used to reconstruct 3-D image,the coronal,sagital and horizoual planes of pelvis were established to confirm the abduction and anteversion of acetabular cup. Matching between cadaver and its 3-D images was performed,and the acetabular cup was implanted in various angle using image based navigation,then the angles were measured with matched goniometers in order to evaluate the accuracy. Reset: Difference of abduction angle between the setting one and real one was (0.46±1.53)°,and that for anteversion angle was (0.79±1.37)°. There was no significant difference between the first and second time of placement of acetabular component with the help of navigation (P>0.05). Conclusions:Reconstruction of reference plane basing on the CT scan data was feasible to confirm the desired orientation of acetabular component. Precise placement of acetabular component in the desired orientation can be achieved by the image based

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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...

  6. 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.

  7. 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

  8. 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.

  9. 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

  10. Acetabular fractures in children and adolescents

    NARCIS (Netherlands)

    Heeg, M; de Ridder, VA; Tornetta, P; de Lange, S; Klasen, HJ

    2000-01-01

    A retrospective study of 29 acetabular fractures in children 2 to 16 years of age with an average followup of 14 years is presented. Nineteen patients had an additional dislocation of the femoral head and 14 patients had an associated neurologic injury. Surgical treatment was performed in 16 patient

  11. Massive acetabular bone loss: Limits of trabecular metal cages

    Directory of Open Access Journals (Sweden)

    Villanueva-Martínez Manuel

    2011-01-01

    Full Text Available Massive acetabular bone loss (more than 50% of the acetabular area can result in insufficient native bone for stable fixation and long-term bone ingrowth of conventional porous cups. The development of trabecular metal cages with osteoconductive properties may allow a more biological and versatile approach that will help restore bone loss, thus reducing the frequency of implant failure in the short-to-medium term. We report a case of massive bone loss affecting the dome of the acetabulum and the ilium, which was treated with a trabecular metal cage and particulate allograft. Although the trabecular metal components had no intrinsic stability, they did enhance osseointegration and incorporation of a non-impacted particulate graft, thus preventing failure of the reconstruction. The minimum 50% contact area between the native bone and the cup required for osseointegration with the use of porous cups may not hold for new trabecular metal cups, thus reducing the need for antiprotrusio cages. The osteoconductive properties of trabecular metal enhanced allograft incorportation and iliac bone rebuilding without the need to fill the defect with multiple wedges nor protect the reconstruction with an antiprotrusio cage.

  12. H/G非骨水泥人工全髋关节置换术后聚乙烯内杯磨损临床研究%Polyethylene wear and osteolysis in H/G cementless total hip arthroplasty

    Institute of Scientific and Technical Information of China (English)

    文立成; 李军; 马忠泰

    2009-01-01

    目的 对H/G非骨水泥人工全髋关节置换术后聚乙烯内杯的磨损及髋臼周围骨溶解的情况进行总结.方法 我院1991至1995年共进行58例(65髋)H/G非骨水泥人工全髋关节置换,其中35例(40髋)获得10年以上随访.对这35例(40髋)患者获得随访的病例,采用计算机数字化方法测量髋臼聚乙烯内杯的二维线性磨损.结果 35例40髋均有不同程度的磨损,磨损范围2~8 mm,平均磨损为(0.32±0.31)mm/年.10髋聚乙烯磨损超过6 mm,髋臼假体周围的骨溶解严重,并伴有金属假体的移位,其中5髋聚乙烯内杯完伞磨透,金属股骨头与金属髋臼相接触;5髋聚乙烯内杯磨损严重伴明显骨溶解,内杯松动.2髋聚乙烯内杯脱位.共实施翻修手术12例,包括更换聚乙烯内杯和金属股骨头2例、金属闩杯翻修2例、全髋翻修8例.28髋在髋臼侧发现骨溶解,其中14髋股骨侧亦有骨溶解发生.结论 本组病例所观测到的H/G髋臼聚乙烯内杯的磨损程度超过文献所报道,而且由于磨损产生的大量磨屑,导致假体周围出现明显骨溶解,直接影响到假体的稳定.关节置换术后应定期随访,避免出现严重骨溶解后增加翻修手术的困难.%Objectives To measure the linear polyethelene wear with use of a computer-assisted two-dimensional method, and to evaluate the relationship between wear and long-term clinic-radiological findings. Methods Between December 1991 and December 1995, the senior author performed 40 primary total hip arthroplasties with use of H/G porous-coated acetabular component Radiographs of 40 H/G cementless total hip arthroplasies were examined for osteolysis, radiolucent line, cup migration and so on. To measure the linear polyethylene wear, migration in the femoral head center relative to the cup shell center was calculated on digitized consecutive radiographs with special computer software program. Results The minimum follow-up was 10 years. Total linear wear

  13. Interface Micromotion of Cementless Hip Stems in Simulated Hip Arthroplasty

    Directory of Open Access Journals (Sweden)

    Mohammed R.A. Kadir

    2009-01-01

    Full Text Available Problem statement: The design of hip prostheses has evolved over time due to various complications found after hip replacement surgery. The currently commercially available cementless femoral stems can be categorized into one of three major types, straight cylindrical, tapered rectangular and anatomical. Each type proposes a unique concept to achieve primary stability-a major requirement for bone healing process. Virtual analyses have been made on individual implants, but comparison between the three major types is required to determine the strength and weaknesses of the design concepts. Approach: Three types of implants were modeled in three dimensions-the straight cylindrical, rectangular taper and anatomical. The size of the three implants was carefully designed to fit and fill the canal of a femur reconstructed from a computed tomography image dataset. Hip arthroplasty was simulated virtually by inserting the hip stem into the femoral canal. Finite element method was used in conjunction with a specialized sub-routine to measure micromotion at the bone-implant interface under loads simulating physiological walking and stair-climbing. Another sub-routine was used to assign bone properties based on the grayscale values of the CT image. Results: All the three types of cementless hip stems were found to be stable under both walking and stair climbing activities. Large micromotion values concentrated around the proximal and distal part of the stems. Conclusion/Recommendations: The three major types of hip stems were compared in this study and all of them were found to be stable after simulated physiological activities.

  14. 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.

  15. Failure analysis of retrieved PE-UHMW acetabular liners.

    Science.gov (United States)

    Laska, Anna; Archodoulaki, Vasiliki-Maria; Duscher, Bernadette

    2016-08-01

    Ultra-high molecular weight polyethylene (PE-UHMW) acetabular liners have a limited lifespan in a patient's body. There are many factors affecting the performance of the implant and furthermore the properties of the polymeric material are changing after implantation. In this work material changes according to structure and morphology and their implication on mechanical properties are in focus. The physical and mechanical properties of ten crosslinked (xL) PE-UHMW and nine conventional (conv) gamma-sterilized PE-UHMW hip components, used as sliding surface in total hip joint replacement, with different in-vivo times are compared. The evaluation of the retrieved acetabular liners is performed in view of crosslinking and conventional gamma-sterilization but also in terms of the influence of gender concerning alteration in properties. The oxidative degradation in the PE-UHMW is investigated by means of Fourier Transformed Infrared Spectroscopy (FTIR). The characterization of the morphology is carried out via differential scanning calorimetry (DSC). A depth profile of the micro-hardness and elastic modulus is taken over the cross-section of the components in order to find the influence of chemical constitution and morphology on the micro-mechanical properties. It could be shown that crosslinking and oxidative degradation influence the degree of crystallinity of the polymer. Oxidation occurs for both types of the material due to in-vivo time. Higher degree of crystallinity can be correlated to higher hardness and indentation modulus. No unequivocal superiority of crosslinked over conventional liners can be observed. The influence of sex concerning alteration of the evaluated properties matters but need to be further investigated.

  16. 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

  17. Clinical observation of particulate cancellous bone impaction grafting in combination with total hip arthroplasty for acetabular reconstruction

    Institute of Scientific and Technical Information of China (English)

    LIU Xian-zhe; YANG Shu-hua; XU Wei-hua; LIU Guo-hui; YANG Cao; LI Jin; YE Zhe-wei; LIU Yong; ZHANG Yu-kun

    2008-01-01

    Objective: To investigate the effect of particulate cancellous bone impaction grafting in combination with total hip arthroplasty (THA) for acetabular reconstruction in patients with posttraumatic arthritis and bone loss afteracetabular fractures.Methods: Totally 15 consecutive cases with unilateral acetabular fracture were treated with bone impaction grafting in combination with THA in our department.There were 10 males and 5 females with mean age of 48.2 years (ranging from 36 to 73 years).Eight cases had the fracture at left hips,7 at right hips.The average age at injury was 28 years (ranging from 18 to 68 years).The mean follow-up period was 4.3 years (ranging from 2 to 7 years).Results: Compared with mean 42 points (ranging from 10 to 62) of the preoperative Harris score,the survival cases at the final follow-up had mean 84 points (ranging from 58 to 98).One patient had mild pain in the hip.No revision of the acetabular or femoral component was undertaken during the follow-up.Normal rotational centre of most hips was recovered except 2 cases in which it was 0.8 mm higher than that in opposite side.All of them had a stable radiographic appearance.Progressive radiolucent fines were observed in I,III zones in 2 cases.One patient had a nonprogressive radiolucent fine in zone III.The cup prosthesis was obviously displaced (6 mm) in one patient,but had not been revised.Conclusion: Particulate cancellous bone impaction grafting in combination with THA as a biological solution is an attractive procedure for acetabular reconstruction in patients with posttraumatic arthritis and bone loss after acetabular fracture,which can not only restore acetabular bone stock but also repair normal hip anatomy and its function.

  18. 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.

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

    Institute of Scientific and Technical Information of China (English)

    WU Li-dong (吴立东); HAHNE H.J.; HASSENPFLUG J.

    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 3 mm 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 0.81 mm and the average gap width was only 0.20 mm. 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 2.97 mm and the average gap width was 0.77 mm. 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.

  20. 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.

  1. Osteochondritis dissecans after rotational acetabular osteotomy for dysplastic hip

    Energy Technology Data Exchange (ETDEWEB)

    Nozawa, Masahiko; Maezawa, Katsuhiko; Yuasa, Takahito; Morimoto, Kouichi; Asakura, Taro; Kurosawa, Hisashi [Juntendo University School of Medicine, Department of Orthopaedic Surgery, Tokyo (Japan)

    2005-12-01

    We encountered a rare case of osteochondritis dissecans of the femoral head after rotational acetabular osteotomy that recovered with conservative treatment 4 years after the detection of characteristic radiological findings. (orig.)

  2. 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

  3. Trabecular metal acetabular revision system (cup-cage construct to address the massive acetabular defects in revision arthroplasty

    Directory of Open Access Journals (Sweden)

    Rajesh Malhotra

    2012-01-01

    Full Text Available The increasing number of total hip replacements in the younger clique has added to the demand for revision procedures. Revision situations are often encountered with infection, loss of bone stock and bone defects. There are various methods of reconstruction of acetabular defects. The management options of type 3B Paprosky acetabular defects are limited with allograft and conventional cages. Trabecular metal technology has evolved to address these bone defects. Trabecular metal acetabular revision system (TMARS cup-cage construct is a new technique to address massive acetabular defects. We describe a case of failed hip reconstruction done for a Giant cell tumour of proximal femur managed by a two stage procedure, initial debridement and second stage reconstruction of acetabulum with TMARS cup-cage construct and femur with allograft prosthesis composite.

  4. 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.

  5. 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

  6. Failure of dual radius hydroxyapatite-coated acetabular cups

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    Zatti Giovanni

    2008-08-01

    Full Text Available Abstract Introduction Many kind of hydroxyapatite-coated cups were used, with favorable results in short term studies; it was supposed that its use could improve osteointegration of the cup, enhancing thus stability and survivorship. The purpose of this study is to analyze the long term behavior of the hemispheric HA coated, Dual Radius Osteonics cup and to discuss the way of failure through the exam of the revised components and of both periacetabular and osteolysis tissue. Materials and Methods Between 1994 and 1997, at the Department of Orthopedic Sciences of the Insubria University, using the posterolateral approach, were implanted 276 Dual Radius Osteonics® in 256 patients, with mean age of 63 years. Results At a mean follow-up of 10 years (range 8–12 years, 183 cups in 165 patients, were available for clinical and radiographical evaluation. 22 Cups among the 183 were revised (11%. The cause of revision was aseptic loosening in 17 cases, septic loosening in one case, periprosthetic fracture in another case, osteolysis and polyethylene wear in two cases and, finally, recurrent dislocations in the last one. In the remaining patients, mean HHS increased from a preoperative value of 50,15 to a postoperative value of 92,69. The mean polyethylene wear was 1,25 mm (min. 0,08, max. 3,9 mm, with a mean annual wear of 0,17 mm. The mean acetabular migration on the two axis was 1,6 mm and 1,8 mm. Peri-acetabular osteolysis were recorded in 89% of the implants (163 cases. The cumulative survivorship (revision as endpoint at the time was 88,9%. Conclusion Our study confirms the bad behavior of this type of cup probably related to the design, to the method of HA fixation. The observations carried out on the revised cup confirm these hypotheses but did not clarify if the third body wear could be a further problem. Another interesting aspect is the high incidence of osteolysis, which are often asymptomatic becoming a problem for the surgeon as the

  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. Effect of proximal femoral osteoporosis on cementless hip arthroplasty: A short-term clinical analysis

    Institute of Scientific and Technical Information of China (English)

    LOU Xian-feng; LI Yu-hong; LIN Xiang-jin

    2007-01-01

    Objective: The aim of this retrospective investigation was to explore the influence of femoral osteoporosis on short-term curative effects of cementless hip arthroplasty and to evaluate the femoral metaphyseal bone mineral density (BMD) for femoral osteoporosis in order to guide prosthesis choice and rehabilitation. Methods: We performed 127 total arthroplasty operations between June 1999 to February 2003 and investigated 49 cementless hip replacements with the Metalcancellous cementless Lubeck Ⅱ system being used in all hips. There were twenty men and twenty-nine women whose mean age at the time of the operation was 60 years (range, 52~81 years). The patients were divided into osteoporosis or normal groups according to the femoral metaphyseal BMD measured preoperatively. The average duration of follow-up was 30 months (range, 8~52 months). We evaluated all of the patients from a clinical standpoint with use of a standard-terminology questionnaire with respect to the short-term curative effects and patients' satisfaction. Hip pain status and functional ability were important indicators of treatment efficacy. Results: Harris hip score and patients' satisfaction in femoral osteoporosis patients who underwent noncemented hip arthroplasty were lower (P=0.004, P=0.03) while the incidence of thigh pain was higher (P=0.03) than the patients with non-osteoporosis. Conclusion: The higher incidence of pain, as well as the decrease in function experienced by the patients in osteoporosis group, supports the case that cementless arthroplasty is not a better choice for those patients and that we had better select prosthesis based on the femoral metaphyseal BMD.

  9. 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.)

  10. Arthroscopic Technique for Acetabular Labral Reconstruction Using Iliotibial Band Autograft.

    Science.gov (United States)

    Chahla, Jorge; Soares, Eduardo; Bhatia, Sanjeev; Mitchell, Justin J; Philippon, Marc J

    2016-06-01

    The dynamic function of the acetabular labrum makes it an important structure for both hip stability and motion. Because of this, injuries to the labrum can cause significant dysfunction, leading to altered hip kinematics. Labral repair is the gold standard for symptomatic labral tears to keep as much labral tissue as possible; however, in cases where the labrum has been injured to such a degree that it is either deficient or repair is not possible, arthroscopic labral reconstruction is preferred. This article describes our preferred approach for reconstruction of the acetabular labrum using iliotibial band autograft.

  11. 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.

  12. Percutaneous acetabuloplasty for metastatic acetabular lesions

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    Logroscino Giandomenico

    2008-05-01

    Full Text Available Abstract Background Osteolytic metastases around the acetabulum are frequent in tumour patients, and may cause intense and drug-resistant pain of the hip. These lesions also cause structural weakening of the pelvis, limping, and poor quality of life. Percutaneous acetabuloplasty is a mini-invasive procedure for the management of metastatic lesions due to carcinoma of the acetabulum performed in patients who cannot tolerate major surgery, or in patients towards whom radiotherapy had already proved ineffective. Methods We report a retrospective study in 25 such patients (30 acetabuli who were evaluated before and after percutaneous acetabuloplasty, with regard to pain, mobility of the hip joint, use of analgesics, by means of evaluation forms: Visual Analog Scale, Harris Hip Score, Western Ontario and McMaster Universities Index of Osteoarthritis (WOMAC, Eastern Cooperative Oncology Group (ECOG. The results obtained were analysed using the χ2 Test and Fisher's exact test. Significance was sent at P Results Marked clinical improvement was observed in all patients during the first six post-operative months, with gradual a worsening thereafter from deterioration of their general condition. Complete pain relief was achieved in 15 of our 25 (59% of patients, and pain reduction was achieved in the remaining 10 (41% patients. The mean duration of pain relief was 7.3 months. Pain recurred in three patients (12% between 2 weeks to 3 months. No major complications occurred. There was transient local pain in most cases, and 2 cases of venous injection of cement without clinical consequences. Conclusion Percutaneous acetabuloplasty is effective in improving the quality of life of patients with osteolytic bone tumours, even though the improvement is observed during the first 6 months only. It can be an effective aid to chemo- and radiotherapy in the management of acetabular metastases.

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

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    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.

  14. Functional outcome of the surgical management of acute acetabular fractures

    Institute of Scientific and Technical Information of China (English)

    Naseem Munshi; Asad Abbas; Mohamed Amirali Gulamhussein; Ghulam Mehboob; Rija Aitzaz Qureshi

    2015-01-01

    Objective:To assess the functional outcome of early surgical management of displaced acetabular fractures and the complications associated with the procedure. Methods: This is a case series study and data was collected using specialized performance. The study included 75 patients and the sampling technique was a non-probability purposive type. Patients presenting with close displaced acetabular fractures of more than 2 mm within 10 days of injury were included. However, elderly patients presenting after 10 days of injury, with evidence of local infection, severe osteoporotic bone and co-morbid such as chronic obstructive pulmonary disease were not included in the study. New acetabular scoring system was used for assessing outcome of patients. Results:A total of 75 patients were operated on. Union was achieved in anatomical position in 66 (88%) patients and in malposition in 9 (12%) patients. Excellent results were obtained in 18 (24%) patients, good results in 41 (54.6%), fair results in 12 (16%), and poor results in 4 (5.4%) patients. Postoperative complications included infection [5 (6.7%)], heterotropic ossification [3 (4%)], sciatic nerve injury [10 (13.3%)], avascular necrosis [3 (4%)] patients. Conclusions: Patients with displaced acetabular fractures should be referred to specialised centres. Early surgical intervention and experienced management is a prime factor in achieving good results.

  15. 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.)

  16. 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.)

  17. Aumento acetabular pela técnica de Stahelli modificada Acetabular increase with modified Stahelli technique

    Directory of Open Access Journals (Sweden)

    Sílvio Pereira Coelho

    2000-09-01

    Full Text Available Os autores apresentam neste trabalho um estudo retrospectivo realizado em 18 pacientes submetidos a tratamento cirúrgico de insuficiência acetabular pela osteotomia da pelve seguindo a técnica descrita por Lynn T. Staheli. Enfatizam a modificação da técnica deste autor, com a introdução do enxerto ósseo, retirado da tábua externa do ilíaco, numa fenda aprofundada até cerca da cortical interna do ilíaco. Os pacientes foram acompanhados através de consultas ambulatoriais previamente a cirurgia e pós-operatoriamente com seguimento que variou de 2 meses a 4 anos no serviço de ortopedia infantil do Hospital Independência - Complexo Hospitalar ULBRA/Porto Alegre-RS. O objetivo do trabalho foi avaliar o quadril acometido pré e pós-operatoriamente, demonstrando a evolução e vantagens da variação da técnica de Staheli desenvolvida neste serviço. Observou-se que a cirurgia, se realizada sob técnica adequada e em mãos experientes, torna-se uma fonte válida de tratamento para aquelas patologias que levam a uma insuficiente cobertura da cabeça femoral.The authors present in this paper a retrospective study of eighteen patients treated surgically for insufficiency of the acetabular coverage with the shelf procedure according to Lynn T. Staheli. This study was done at the Service of Pediatric Orthopedics of Hospital Independência - Complexo Hospitalar ULBRA/Porto Alegre-RS. They call attention to the modification of the surgical technique in that the bone graft taken from outer cortex of the iliac bone, is deepened in the slot in the superior rim of the acetabulum. The follow-up ranged from two months to four years. The aim of this paper was to evaluate the affected hip pre and postoperatively showing the results and the advantages of the modified shelf technique. They observed that if the surgery is performed according to the correct technique and by an experienced surgeon, it is a very good alternative to the treatment of those

  18. 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.)

  19. 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...

  20. 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

  1. 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.)

  2. 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.)

  3. 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.

  4. 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

  5. Early total hip arthroplasty for severe displaced acetabular fractures

    Institute of Scientific and Technical Information of China (English)

    YANG Shu-hua; ZHANG Yu-kun; XU Wei-hua; LI Jin; LIU Guo-hui; YANG Cao; LIU Yong; TIAN Hong-tao

    2006-01-01

    Objective : To investigate the effect of early total hip arthroplasty for severe displaced acetabular fractures.Methods: Total hip arthroplasty was performed on 17 cases of severe fracture of the acetabulum from 1997 to 2003. The mean follow-up was 2.1 years (1-6 years) and the average period from fracture to operation was 8 days (5-21 day). The average age of the patients was 53 years (26-69 years).Results: At the final follow-up the Harris hip score averaged 82(69-100) points and 15 cases have got a good outcome. There was one case of heterotopic bone formation. There were no radiographic evidences of late loosening of the prosthesis. One patient had severe central displacement of the cup.Conclusions: In patients with severe displaced acetabular fractures, particularly in elderly patients, early total hip arthroplasty is probably an alternative efficient way to achieve a painless and stable hip.

  6. 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.)

  7. Multiplanar and 3D CT of acetabular fractures

    Energy Technology Data Exchange (ETDEWEB)

    Haveri, M.; Suramo, I.; Laehde, S. [Oulu Univ., Dept. of Diagnostic Radiology (Finland); Junila, J. [Oulu Univ., Dept. of Orthopaedic Surgery (Finland)

    1998-05-01

    Purpose: To establish a standard protocol for the multiplanar (MPR) and 3D shaded surface display (SSD) reconstruction of CT data on acetabular fractures, and to assess the usefulness of these reformats. Material and Methods: Acetabular fractures in 15 patients were imaged by means of plain radiographs, transaxial CT, MPR reformats, and SSD reformats. Results: The classification of the acetabular fracture was revised in 7/15 cases when the transaxial CT images were read after the plain radiographs. Although the MPR and SSD reformats did not alter the classification, they did add to the degree of confidence in the diagnosis in 9/15 cases. In 2 patients, the MPR and SSD reformats indicated operative instead of conservative treatment. In the MPR reformats, the following views were considered essential in all cases: (a) along the anterior column; (b) along the posterior column; and (c) along both columns and the inferior ramus. In the SSD reformats, the following views were considered essential in all cases: (d) the latero-caudal en face view into the acetabulum; and 180 opposite to this, (e) the medio-cranial view (facing the quadrilateral plate). In 10/15 cases, these views were all that was needed for classification. It was, however, essential to remove the femur from the images before reconstructing the SSD views. Conclusion: Complex acetabular fractures with displacement should be evaluated by means of transaxial CT and additional MPR and SSD reformats. The use of appropriate standard MPR and SSD views shortens the time required to produce the reformats and thereby maximizes the benefit gained. (orig.).

  8. 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...

  9. 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

  10. 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...

  11. 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

  12. 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.

  13. 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.

  14. 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...

  15. 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.

  16. 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.)

  17. Osseointegration: a review of the fundamentals for assuring cementless skeletal fixation

    Directory of Open Access Journals (Sweden)

    Isaacson BM

    2014-04-01

    Full Text Available Brad M Isaacson,1,2 Sujee Jeyapalina3,4 1Henry M Jackson Foundation for the Advancement of Military Medicine, 2The Center for Rehabilitation Sciences Research, Department of Physical Medicine and Rehabilitation, Uniformed Services University of Health Sciences, Bethesda, MD, USA; 3Department of Orthopedics, 4Orthopedic Research Laboratory, University of Utah, Salt Lake City, UT, USA Abstract: Direct skeletal fixation, termed osseointegration, has expanded in the last century and includes use in total joint replacements, the edentulous mandible and maxilla, and percutaneous osseointegrated prosthetics. Although it is well known that titanium and bone have the ability to form a durable bone–implant interface, new applications have emerged in the field of orthopedics, which requires a more thorough assessment of the literature. This review aims to introduce the basic biological principles for attaining osseointegration and discusses the major factors for assuring successful cementless fixation. Keywords: osseointegration, bone, skeletal attachment, total joint replacements, dental implants, percutaneous

  18. 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.

  19. 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.

  20. 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.

  1. 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)

  2. 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.

  3. 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.

  4. 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...

  5. 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...

  6. 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...

  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. 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.)

  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. 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.)

  11. 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.

  12. 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

  13. Quantitative Computerized Assessment of the Degree of Acetabular Bone Deficiency: Total radial Acetabular Bone Loss (TrABL

    Directory of Open Access Journals (Sweden)

    Frederik Gelaude

    2011-01-01

    Full Text Available A novel quantitative, computerized, and, therefore, highly objective method is presented to assess the degree of total radical acetabular bone loss. The method, which is abbreviated to “TrABL”, makes use of advanced 3D CT-based image processing and effective 3D anatomical reconstruction methodology. The output data consist of a ratio and a graph, which can both be used for direct comparison between specimens. A first dataset of twelve highly deficient hemipelves, mainly Paprosky types IIIB, is used as illustration. Although generalization of the findings will require further investigation on a larger population, it can be assumed that the presented method has the potential to facilitate the preoperative use of existing classifications and related decision schemes for treatment selection in complex revision cases.

  14. 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

  15. 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

  16. 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.

  17. 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.

  18. 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

  19. 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

  20. 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.

  1. Surface-gradient cross-linked polyethylene acetabular cups: oxidation resistance and wear against smooth and rough femoral balls.

    Science.gov (United States)

    Shen, Fu-Wen; McKellop, Harry

    2005-01-01

    Two methods were developed and evaluated for cross-linking the bearing surface of a polyethylene acetabular cup to a limited depth, in order to improve its resistance to wear without degrading the mechanical properties of the bulk of the component. In the first method, low-energy electron beams were used to cross-link only the bearing surface of the cups to a maximum depth of about 2 mm. The cups then were annealed at 100 degrees C in vacuum for 3 or 6 days to reduce the residual free radicals, and the resultant resistance to oxidation was compared by artificially aging the cups at 80 degrees C in air. Chemically cross-linked surface layers were produced by coating the bearing surfaces of the cups with a thin layer of polyethylene powder mixed with 1% weight peroxide, and compressing them at 6.9 MPa (1000 psi) and 170 degrees C. This resulted in a cross-linked surface layer that extended about 3 mm deep, with a gradual transition to conventional (noncross-linked) polyethylene in the bulk of the implant. In hip simulator wear tests with highly polished (implant quality) femoral balls, both types of surface cross-linking were found to improve markedly the wear resistance of the acetabular cups. In tests with roughened femoral balls, the wear rates were much higher and were comparable to those obtained with similarly roughened balls against noncross-linked polyethylene cups in a previous study, indicating that the full benefit of cross-linking may not be realized under conditions of severe third-body abrasion. Nevertheless, these results show a promising approach for optimizing the wear resistance and the bulk mechanical properties of polyethylene components in total joint arthroplasty.

  2. Pelvic Incidence: A Predictive Factor for Three-Dimensional Acetabular Orientation—A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Christophe Boulay

    2014-01-01

    Full Text Available Acetabular cup orientation (inclination and anteversion is a fundamental topic in orthopaedics and depends on pelvis tilt (positional parameter emphasising the notion of a safe range of pelvis tilt. The hypothesis was that pelvic incidence (morphologic parameter could yield a more accurate and reliable assessment than pelvis tilt. The aim was to find out a predictive equation of acetabular 3D orientation parameters which were determined by pelvic incidence to include in the model. The second aim was to consider the asymmetry between the right and left acetabulae. Twelve pelvic anatomic specimens were measured with an electromagnetic Fastrak system (Polhemus Society providing 3D position of anatomical landmarks to allow measurement of acetabular and pelvic parameters. Acetabulum and pelvis data were correlated by a Spearman matrix. A robust linear regression analysis provided prediction of acetabulum axes. The orientation of each acetabulum could be predicted by the incidence. The incidence is correlated with the morphology of acetabula. The asymmetry of the acetabular roof was correlated with pelvic incidence. This study allowed analysis of relationships of acetabular orientation and pelvic incidence. Pelvic incidence (morphologic parameter could determine the safe range of pelvis tilt (positional parameter for an individual and not a group.

  3. 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.

  4. 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.

  5. 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

  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. 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.)

  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. Central acetabular fracture with dislocation treated by minimally invasive plate osteosynthesis.

    Science.gov (United States)

    2015-06-01

    Central acetabular fractures with dislocation are usually the result of high-energy trauma, resulting in joint incongruity, and are frequently associated with other injuries. Open reduction and internal fixation has been the standard treatment for acetabular fractures, but it is associated with extensive surgical trauma, and complications such as haematoma formation, iatrogenic nerve injury, and heterotopic ossification. We present the case of a 63-year-old female who sustained a central acetabular fracture of the hip with dislocation as a result of an automobile collision. Closed reduction of the dislocation was performed, and the fracture was managed by minimally invasive plate osteosynthesis using a specially prepared plate. At 01 year postoperatively, radiographs showed the fracture to have been well-healed with good congruity of the joint. However, heterotopic ossification of the joint was noted. The technique allowed reduction of the fracture with minimal surgical trauma.

  10. 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.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Williams, T.R. [Portsmouth Naval Medical Center, Radiology Department, Charette Health Care Center, Portsmouth, VA (United States); Puckett, M.L.; Shin, A.Y.; Gorman, J.D. [Naval Medical Center San Diego, Radiology Department, San Diego, CA (United States); Denison, G. [US Naval Hospital Guam (United States)

    2002-05-01

    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.)

  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. Application of porous tantalum in acetabular revision after total hip arthroplasty%多孔金属钽髋臼在全髋关节置换术后髋臼翻修中的应用

    Institute of Scientific and Technical Information of China (English)

    李亮; 赵阳; 王志强

    2013-01-01

    To review the application effects of the porous tantalum acetabular cup in acetabular revision for acetabular failure after total hip arthroplasty ( THA ). The related literatures about the characteristics of porous tantalum and its application in acetabular revision in recent 10 years were retrieved from China National Knowledge Internet ( CNKI ) and PubMed databases, and a review was made. The porous tantalum acetabular cup had unique high porosity, low elasticity, high friction coefficient and good function to promote bone ingrowth inwardly. Good clinical results could be obtained using the porous tantalum acetabular cup in acetabular revision for patients with initial fixation failure using the artificial acetabular cup. In acetabular revision, the porous tantalum acetabular cup can provide superior mechanical stability, with good early and medium-term results.

  14. 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.)

  15. Biomechanical Study of Acetabular Tridimensional Memoryalloy Fixation System

    Science.gov (United States)

    Liu, Xin-Wei; Xu, Shuo-Gui; Zhang, Yun-Tong; Zhang, Chun-Cai

    2011-07-01

    We developed the acetabular tridimensional memoryalloy fixation system (ATMFS), which is made of NiTi shape memory alloy, according to the specific mechanical properties of biological memory material, NiTi shape memory alloy and measured distribution of contact area and pressure between the acetabulum and the femoral head of cadaveric pelvis. Seven formalin-preserved cadaveric pelves were used for this investigation. Pressure-sensitive film was used to measure contact area and pressure within the anterior, superior, and posterior regions of the acetabulum. The pelves were loaded under the following four conditions: (1) intact; (2) following a creation posterior wall fracture defect; (3) following reduction and standard internal fixation with reconstruction plate; and (4) following reduction and internal fixation with a new shape memory alloy device named ATMFS. A posterior wall fracture was created along an arc of 40° to 90° about the acetabulur rim. Creation of a posterior wall defect resulted in increased load in the superior acetabulum (1485 N) as compared to the intact condition (748 N, P = 0.009). Following reduction and internal fixation, the load distributed to the superior acetabulum (1545 N) was not statistically different from the defect condition. Following the fixation with ATMFS, the load seen at the superior region of the actabulum (964 N) was familiar with fixation with reconstruction plate and was not different from intact state ( P = 0.45). These data indicate that the use of ATMFS as a fracture internal fixation device resulted a partial restoration of joint loading parameters toward the intact state. ATMFS fixation may result in a clinical benefit.

  16. 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

  17. 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.

  18. 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

    BACKGROUND AND PURPOSE: An acetabular labral tear is a diagnostic challenge. Various clinical tests have been described, but little is known about their diagnostic sensitivity and specificity. We investigated the diagnostic validity of clinical tests and ultrasound as compared with MR arthrograph...

  19. Bone impaction grafting and a cemented cup after acetabular fracture at 3-18 years.

    NARCIS (Netherlands)

    Schreurs, B.W.; Zengerink, M.; Welten, M.L.M.; Kampen, A. van; Slooff, T.J.J.H.

    2005-01-01

    The outcome of total hip arthroplasty after acetabular fracture is compromised. We studied if the bone impaction grafting technique could provide long-term prosthesis survival in deformed and irregular acetabula. We studied 20 hips in 20 patients (mean age, 53.3 years; range, 35-75 years) that were

  20. 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.

  1. 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

  2. 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

  3. 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 preva...

  4. 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 of 42 (0...

  5. 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

  6. 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.

  7. 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...

  8. Intra-articular injection of tranexamic acid via a drain plus drain-clamping to reduce blood loss in cementless total knee arthroplasty

    Directory of Open Access Journals (Sweden)

    Mutsuzaki Hirotaka

    2012-09-01

    Full Text Available Abstract Background Patients undergoing cementless total knee arthroplasty (TKA sometimes suffer large blood loss. In a retrospective study, we explored whether postoperative intra-articular retrograde injection of tranexamic acid (TA and leaving a drain clamp in place for 1 h reduced blood loss. Patients and methods Patients (n = 140 treated with unilateral primary cementless TKA (posterior cruciate ligament retained were divided into two groups: those who had an intra-articular injection of TA (1000 mg and drain clamping for 1 h postoperatively (study group, n = 70 and those who were not given TA and did not undergo clamping of their drains (control group, n = 70. Postoperative total blood loss, volume of drainage, hemoglobin level, transfusion amounts and rates, D-dimer level at postoperative day (POD 7, and complications were recorded. Results Total blood loss, total drainage, mean transfusion volume, and transfusion rates were lower in the study group than in controls (P P P  Conclusions Immediately postoperative intra-articular retrograde injection of TA and 1 h of drain-clamping effectively reduced blood loss and blood transfusion after cementless TKA. We believe that this method is simple, easy, and suitable for these patients.

  9. 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

  10. 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...

  11. Corrosion on the acetabular liner taper from retrieved modular metal-on-metal total hip replacements.

    Science.gov (United States)

    Gascoyne, Trevor C; Dyrkacz, Richard M; Turgeon, Thomas R; Burnell, Colin D; Wyss, Urs P; Brandt, Jan-M

    2014-10-01

    Eight retrieved metal-on-metal total hip replacements displayed corrosion damage along the cobalt-chromium alloy liner taper junction with the Ti alloy acetabular shell. Scanning electron microscopy indicated the primary mechanism of corrosion to be grain boundary and associated crevice corrosion, which was likely accelerated through mechanical micromotion and galvanic corrosion resulting from dissimilar alloys. Coordinate measurements revealed up to 4.3mm(3) of the cobalt-chromium alloy taper surface was removed due to corrosion, which is comparable to previous reports of corrosion damage on head-neck tapers. The acetabular liner-shell taper appears to be an additional source of metal corrosion products in modular total hip replacements. Patients with these prostheses should be closely monitored for signs of adverse reaction towards corrosion by-products.

  12. An Automated Size Recognition Technique for Acetabular Implant in Total Hip Replacement

    CERN Document Server

    Shapi'i, Azrulhizam; Hasan, Mohammad Khatim; Kassim, Abdul Yazid Mohd; 10.5121/ijcsit.2011.3218

    2011-01-01

    Preoperative templating in Total Hip Replacement (THR) is a method to estimate the optimal size and position of the implant. Today, observational (manual) size recognition techniques are still used to find a suitable implant for the patient. Therefore, a digital and automated technique should be developed so that the implant size recognition process can be effectively implemented. For this purpose, we have introduced the new technique for acetabular implant size recognition in THR preoperative planning based on the diameter of acetabulum size. This technique enables the surgeon to recognise a digital acetabular implant size automatically. Ten randomly selected X-rays of unidentified patients were used to test the accuracy and utility of an automated implant size recognition technique. Based on the testing result, the new technique yielded very close results to those obtained by the observational method in nine studies (90%).

  13. 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.

  14. Magnetic resonance imaging of para-acetabular insufficiency fractures in patients with malignancy

    Energy Technology Data Exchange (ETDEWEB)

    Theodorou, S.J. [Department of Radiology, School of Medicine, University of California, San Diego Medical Center, San Diego, CA (United States)]|[Department of Radiology, Veterans Administration Medical Center, San Diego, CA (United States)]|[Department of Clinical Radiology, University of Manchester, Manchester (United Kingdom); Theodorou, D.J. [Department of Radiology, School of Medicine, University of California, San Diego Medical Center, San Diego, CA (United States)]|[Department of Radiology, Veterans Administration Medical Center, San Diego, CA (United States)]. E-mail: daphne_theodorou@hotmail.com; Schweitzer, M.E. [Department of Radiology, New York University Hospital for Joint Diseases, NY (United States); Kakitsubata, Y. [Department of Radiology, School of Medicine, University of California, San Diego Medical Center, San Diego, CA (United States)]|[Department of Radiology, Veterans Administration Medical Center, San Diego, CA (United States); Resnick, D. [Department of Radiology, School of Medicine, University of California, San Diego Medical Center, San Diego, CA (United States)]|[Department of Radiology, Veterans Administration Medical Center, San Diego, CA (United States)

    2006-02-15

    AIM: To describe the characteristic magnetic resonance imaging (MRI) findings of para-acetabular insufficiency fractures in patients with malignancy, and compare the MRI appearance of these fractures with that of metastatic bone disease. MATERIALS AND METHODS: MRI examinations were reviewed in 16 patients with a known malignant tumour and severe hip pain that raised the possibility of local recurrence or metastatic disease. Six patients had received pelvic irradiation, and three patients were receiving steroid medication. RESULTS: The total number of fractures detected was 21: a solitary fracture was present in 11 patients and five patients had bilateral para-acetabular fractures. Two patients had associated sacral insufficiency fractures, and one of them had stress fractures involving both acetabular columns. Conventional radiography allowed the diagnosis of 14 (67%) fractures; six (28%) radiographic examinations were negative; and one (5%) examination was equivocal for fracture. Available scintigraphic and computed tomography (CT) studies revealed typical findings of fracture. Using MRI, insufficiency fractures appeared as linear regions of low signal intensity on T1- and T2-weighted images. Marked marrow oedema was evident in all cases. Fractures characteristically were parallel to the superior acetabulum in a curvilinear fashion in 18 (86%) instances, and were oblique in three (14%) instances. The fractures demonstrated considerable enhancement after intravenous gadolinium administration. No associated soft tissue masses were documented. CONCLUSION: Para-acetabular insufficiency fractures are a cause of hip pain, which may mimic skeletal metastasis in the patient with malignancy and pelvic irradiation. Recognition of the characteristic MRI findings of these fractures can preclude misdiagnosis and unnecessary bone biopsy.

  15. 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...

  16. Long-term outcome of operative management of delayed acetabular fractures

    Institute of Scientific and Technical Information of China (English)

    ZHU Shi-wen; SUN Xu; YANG Ming-hui; LI Yu-neng; ZHAO Chun-peng; WU Hong-hua; CAO Qi-yong

    2013-01-01

    Background Surgical treatment of acetabular fracture has long been a challenging area in the field of orthopedic trauma.The aim of this research was to investigate the operative methods for delayed acetabular fractures and to assess the operation results.Methods The operative approaches,procedures,results,and complications of the delayed acetabular fractures between 1995 and 2005 were retrospectively evaluated at Beijing Jishuitan Hospital.Quality of life was assessed for each patient with the Merle d'Aubingne and Postel fracture function rating scale and the radiological result was assessed using the Matta radiological score.Results Sixty-eight cases (70 hips) were followed up with a minimal duration of five years (average of 5.8 years).Excellent functional results were observed in 10 hip joints,good results in 40,fair results in 11,and poor results in nine.The risks of poor prognosis include impact fracture or osteochondral fracture of femoral head,a time beyond 42 days from injury to operative management,and dislocation of femoral head during the injury.Some of the problems,which were observed included postoperative infection in two hips,iatrogenic sciatic nerve injury in eight hips,traumatic arthritis in 15 hips,heterotopic ossification in 17 hips,and necrosis of the femoral head in six hips.Conclusion A careful selection of operative indications for delayed acetabular fractures in combination with a proper ooerative aPProach and appropriate reduction and fixation could guarantee relatively good results.

  17. 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...

  18. 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.

  19. 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

  20. 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

  1. 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.

  2. 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

  3. Magnetic resonance imaging and magnetic resonance arthography of the acetabular labrum: Comparison with surgical findings; Magnetresonanztomographie und Magnetresonanzarthrographie des Labrum acetabulare: Vergleich mit operativen Ergebnissen

    Energy Technology Data Exchange (ETDEWEB)

    Czerny, C. [Universitaetsklinik fuer Radiodiagnostik, Vienna (Austria). Abt. fuer Osteologie; Kramer, J. [Universitaetsklinik fuer Radiodiagnostik, Vienna (Austria). Abt. fuer Osteologie; Institut fuer bildgebende Diagnostik am Schillerpark, Linz (Austria); Neuhold, A. [Krankenhaus Rudolfinerhaus, Vienna (Austria). Inst. fuer bildgebende Diagnostik; Urban, M. [Krankenhaus Sozialmedizinisches Zentrum Ost, Vienna (Austria). Abt. fuer Radiodiagnostik; Tschauner, C. [Orthopaedisches Landeskrankenhaus Stolzalpe (Austria); Hofmann, S. [Krankenhaus Sozialmedizinisches Zentrum Ost, Vienna (Austria). Abt. fuer Radiodiagnostik; Orthopaedisches Landeskrankenhaus Stolzalpe (Austria)

    2001-08-01

    Aim of the study: To evaluate the accuracy of magnetic resonance imaging (MRI) and magnetic resonance (MR) arthrography in detecting acetabular labral lesions in correlation to surgical findings. Patients and methods: Forty patients (40 hips) with chronic hip pain and a strong clinical suspicion of labral lesions were examined with MRI in the coronal and axial plane by obtaining T{sub 1} weighted and proton density-weighted spin echo sequences. Additionally, MR arthrography of the high joint in the coronal oblique and sagittal oblique plane was performed by obtaining T{sub 1}-weighted three-dimensional gradient echo sequences after the intraarticular injection of gadopentate dimeglumine. The labra were prospectively evaluated on the basis of morphology, signal intensity, the presence or absence of a tear, and their attachment to the acetabulum. All patients underwent surgery, and the MRI findings and MR arthrography findings were compared with the surgical results. Results: Surgically, 34 labral lesions, and 6 normal labra were detected. MRI correctly depicted labral lesions in 24 patients and two normal labra, and MR arthrography correctly depicted labral lesions in 30 patients and 5 normal labra compared with the surgical results. The sensitivity of MRI was 80%, the accuracy of MRI was 65%, the sensitivity of MR arthrography was 95%, and the accuracy of MR arthgrography was 88%. Conclusions: MR arthrography enables considerably more accurate detection of acetabular labral lesions than MRI. MR arthrography should be the method of choice for the diagnosis of the presence or absence of acetabular labral lesions in patients with chronic hip pain and a strong clinical suspicion of labral lesions. (orig.) [German] Ziel: Die Bestimmung der Wertigkeit der konventionellen Magnetresonanztomographie (MRT) und der Magnetresonanzarthrographie (MR-Arthrographie) in der Abklaerung von Laesionen des Labrum acetabulare im Vergleich mit Operationsbefunden (Goldstandard). Methode

  4. Magnetic resonance imaging evaluation of acetabular orientation in normal Chinese children.

    Science.gov (United States)

    Li, YiQiang; Liu, YuanZhong; Zhou, QingHe; Chen, WeiDong; Li, JingChun; Yu, LingJia; Xu, HongWen; Xie, DengHui

    2016-09-01

    There are no data regarding the acetabular orientation on magnetic resonance imaging (MRI); this study investigates the changes of acetabular orientation with age in normal Chinese children.We retrospectively analyzed the medical records of children who underwent hip MRI examination at our hospital from January 2009 to December 2015. A total of 180 patients with normal MRI reading of the hip joints were included and were divided into 14 groups according to age: from 6 months of age and then for each year from 1 to 16 years. The bony and cartilage acetabular anteversion angle (AAA), acetabular inclination angle (AIA), and acetabular index (AI) were measured. Total bony and cartilage femoral head coverage angles were measured on axial section total femoral head coverage angle (a-TCA) and coronal section total femoral head coverage angle (c-TCA).The mean bony AAA and AIA were 12.2 ± 2.5° and 50.9 ± 2.5°, respectively; both of them stayed constant from the age of 6 months to 16 years. Similar results were found in cartilage AAA (12.1 ± 2.5°) and AIA (41.2 ± 3.0°). There was no difference between bony and cartilage AAA, but bony AIA was significantly larger than cartilage AIA. Bony AI was 24.1 ± 2.4° at the age of 6 months, decreasing to 12.5 ± 2.3° by 12 to 13 years of age; cartilage AI (5.9 ± 1.7°) maintained a steady value with age. The mean bony a-TCA and c-TCA at 6 months were 117.0 ± 5.8° and 127.5 ± 5.1°, increasing to 144.5 ± 4.6° and 140.7 ± 2.5° at the age of 16 years. However, the cartilage a-TCA (145.2 ± 7.2°) and c-TCA (154.1 ± 5.7°) did not change significantly with age.Both bony and cartilage AAA and AIA remain constant up to the age of 16 years in normal Chinese pediatric population. Although the cartilage coverage of femoral head by the acetabulum remains unchanged with age, the bony coverage of femoral head increases. PMID:27631258

  5. 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

  6. Correlative analysis of MRI-evident abductor hip muscle degeneration and power after minimally invasive versus conventional unilateral cementless THA.

    Science.gov (United States)

    Vasilakis, Ioannis; Solomou, Ekaterini; Vitsas, Vasilis; Fennema, Peter; Korovessis, Panagiotis; Siamblis, Dimitrios K

    2012-12-01

    The 2 main null hypotheses of this study were: (1) the 4-year surgical trauma-related degeneration within the hip abductor muscles after a minimally invasive approach to total hip arthroplasty would be similar to that following a conventional approach; and (2) no differences in perioperative blood loss or postoperative hip pain would be observed between the minimally invasive and conventional approaches.In 40 consecutive randomly selected adult patients with unilateral primary hip osteoarthritis, a cementless Zweymüller-Plus THA (Smith & Nephew Orthopaedics, Baar, Switzerland) was implanted by a single surgeon in 1 institution during the same period. Twenty patients underwent a minimally invasive approach (group A), and 20 patients underwent a conventional anterolateral approach (group B). Four years postoperatively, the operated and contralateral nonoperated hips of 37 available patients from both groups were examined with magnetic resonance imaging to show any changes in the gluteus medius and tensor fascia latae. Simultaneously, hip abductor power was measured bilaterally in both groups. Anthropometric data, blood loss, Short Form 36 self-assessment questionnaire, visual analog pain score, and walking distance were also analyzed.The reliability of magnetic resonance imaging and hip abductor power measurements was high. No difference was found in hip abductor power on the operated side between the 2 groups, whereas hip abductor power on the nonoperated side was significantly higher in both groups. This study revealed no mechanical and functional benefits in favor of patients undergoing minimally invasive vs conventional total hip arthroplasty.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. 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.

  9. 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.)

  10. 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.)

  11. 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

    and 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...

  12. 陀螺仪在全髋置换髋臼杯定位中的应用%Application of gyroscope to acetabular cup positioning in total hip arthroplasty

    Institute of Scientific and Technical Information of China (English)

    葛兴涛; 葛兴华; 尚春暖; 王增涛

    2014-01-01

    BACKGROUND:Good position of acetabular prosthesis during total hip replacement plays a key role in success of the operation. Traditional location tool has poor accuracy, is too complicated, and limits its application. OBJECTIVE:To compare the advantages and disadvantages of gyroscope with the traditional technique in acetabular component orientation in total hip arthroplasty. METHODS:Using lateral approach, physicians with different experiences used traditional technique to locate acetabular cup 100 times (20 times in each person; 40° abduction and 15° anteversion), and then used gyroscope to locate 60 times at the same angle in the same plastic hip model. The error between the planed and measured values was recorded. RESULTS AND CONCLUSION: Compared to the traditional technique, the error of the abduction and anteversion decreased obviously. These indicated that the gyroscope can make the orientation of acetabular component more precise in total hip arthroplasty.%背景:全髋置换中良好的髋臼假体方位对于手术的成功起到了至关重要的作用。传统定位工具或精确度欠佳、或太过繁琐,限制了其应用。  目的:对比陀螺定位仪与传统定位技术在全髋置换髋臼杯定位中的优劣。  方法:应用外侧入路,在同一个塑料髋部模型上由不同经验年限的医生利用传统方法进行了100次髋臼杯定位(每人20次40°外展和15°前倾);再利用陀螺定位仪分别进行了60次相同角度的定位,记录实测角度与事先设定角度的误差。  结果与结论:与传统技术相比,使用螺仪定位仪测量的外展角和前倾角误差明显下降。提示陀螺定位仪能使全髋置换中髋臼杯的定位更加精确。

  13. 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

  14. 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.

  15. 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.

  16. Modified ilioinguinal approach in combined surgical exposures for displaced acetabular fractures involving two columns.

    Science.gov (United States)

    Wang, Peng; Zhu, Xiaodong; Xu, Peng; Zhang, Yan; Wang, Lubo; Liu, Xiangyan; Mu, Weidong

    2016-01-01

    The purpose of this study is to assess the advantages of modified ilioinguinal approach in combined surgical exposures for displaced acetabular fractures involving two columns management. 73 patients with displaced acetabular fractures involving two columns underwent open reduction and internal fixation through combined surgical approaches between 2006 and 2014 in our hospital. The modified ilioinguinal approach combined with Kocher-Langenbeck approach group (group A) included 46 patients. The standard ilioinguinal approach combined with Kocher-Langenbeck approach group (group B) included 27 patients. Outcome was assessed in operative time, blood loss, function outcomes and complications. In group A, the average operative time was 123.2 min, and the average blood loss was 586.2 ml. Anatomic reduction was achieved in 39 patients (84.8 %). The functional recovery was good in 37 patients (80.4 %). Complications related to the approach were observed in 10 patients (21.7 %). In group B, the average operative time was 161.5 min, and the average blood loss was 830 ml. Anatomic reduction was achieved in 24 patients (88.9 %). The functional recovery was good in 22 patients (81.5 %). Complications related to the approach were observed in 9 patients (33.3 %). This study demonstrates that both combined approaches permits good postoperative function results for treatment of acetabular fractures involving two columns. However, the modified ilioinguinal approach combined with Kocher-Langenbeck approach provides less operative time, blood loss and complications. PMID:27652175

  17. 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.

  18. 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

  19. Percutaneous Fixation of Anterior Column Acetabular Fracture in a Renal Transplant Recipient

    Directory of Open Access Journals (Sweden)

    Halil Ceylan

    2013-01-01

    Full Text Available Renal transplantation, performed per million population, ranges from 30 to 60 in developed countries. The transplanted kidney is generally placed in iliac fossa; therefore the treatment procedure of the pelvic trauma in these patients should be selected carefully. The gold standard technique for the treatment of displaced acetabulum fractures is open reduction and internal fixation. Our patient had received a living-related-donor renal transplant due to chronic renal failure. In the second year of transplantation, she had been injured in a motor-vehicle accident, and radiographs showed a right acetabular anterior column fracture and left pubic rami fractures. The patient was treated with percutaneous fixation techniques and at one year of postoperative period there was no evidence of degenerative signs and the clinical outcome was good. Beside having the advantage of avoiding dissection through the iliac fossa by the standard ilioinguinal approach, percutaneous techniques, with shorter surgical time, decreasing soft tissue disruption, and the potential for early discharge from hospital might be ideal for a renal transplant recipient carrying a higher risk of infection. Percutaneous fixation of selected acetabular fractures in a renal transplant recipient would presumably have the potential to decrease the morbidity associated with traditional open surgical procedures.

  20. 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)

  1. The Association of Femoral Neck Stress Fractures with Femoral Acetabular Impingement

    Science.gov (United States)

    Safran, Marc R.; Goldin, Michael; Anderson, Christian; Fredericson, Michael; Stevens, Kathryn J.

    2013-01-01

    Objectives: To determine if there is an increased incidence of femoral acetabular impingement (FAI) in patients presenting with stress fractures of the femoral neck. Methods: After IRB approval, the imaging studies of 25 athletes (22 females, 3 males, mean age 26, range 19 - 39 years) with femoral neck stress injuries were assessed for the presence of features suggesting FAI, including acetabular retroversion, coxa profunda, abnormal femoral head-neck junction, fibrocystic change, os acetabulae, labral tear and chondral injury. All subjects had to have an adequate AP Pelvis radiograph, a lateral radiograph of the affected hip, and an MRI of the affected hip. The alpha angle, anterior offset ratio, and center to edge (CE) angle were measured on radiographs. The grade of stress injury was determined on MR images. All images and measurements were made by a musculoskeletal fellowship trained radiologist, a fellowship trained orthopaedic surgeon, an orthopaedic sports medicine fellow and a physical medicine and rehabilitation resident. Charts were reviewed to determine treatment of the stress fracture, outcome and final follow up, as well as to determine if the patient had any further treatment for their hip. Results: Of the 25 hips (18 right, 7 left) with femoral neck stress reactions, 9 were grade 2 (bone marrow edema), 5 were grade 3 (high T2 and low T1 marrow signal), and 11 were grade 4 (stress fracture). Twenty patients (80%) had coxa profunda - where the floor of the cotyloid fossa touches or extends beyond the ilioischial line (incidence in general population is 15.2% of males, and 19.4% of females). Coxa profunda, defined by the floor of the cotyloid fossa touching or extending beyond the ilioischial line and a center edge angle of more than 35o, was present in 28% of subjects. Acetabular retroversion as assessed by the crossover sign was present in 42% (normal incidence is 5% of population). Center edge angle was greater than 35o in 20% and greater than 40 o

  2. 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 th...

  3. 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.

  4. [Acetabular Osteolysis in Total Hip Replacement - When to Retain the Cup?].

    Science.gov (United States)

    Lutz, B; Faschingbauer, M; Bieger, R; Reichel, H; Kappe, T

    2016-08-01

    Periacetabular osteolysis is a frequent long-term complication of cementless total hip arthroplasty. The decision whether to retain or to revise a cup in the presence of osteolysis remains a challenge. The options are regular clinical and radiological check-ups, isolated liner exchange with and without bone grafting, and complete cup revision. Thorough preoperative diagnostics, including a medical history, examination and imaging, are mandatory for correct decision making. In most patients, computed tomography is useful to assess periacetabular osteolysis. If the cup is well-fixed and positioned in an asymptomatic patient without progressive osteolysis and no implant defect or higher grade polyethylene wear and no signs of infection, continuous clinical and radiological monitoring is preferred. If imaging reveals cup loosening, malposition, osteolysis localised in a weight-bearing area, imminent or present periprosthetic fractures, rapid progressive osteolysis, implant defects or massive inlay wear, surgical treatment may be preferred. Cup revision is usually performed in such patients. If the cup is well-positioned and well-fixed in the X-ray, the procedure has to be discussed with the patient individually. Apart from patient-specific risk factors, the risk of further progression has to be assessed. Isolated liner exchange can be performed if the patient is asymptomatic and the cup proves to be stable intraoperatively. It is still unclear whether filling osteolyses through screw holes or osseous windows is of long-term benefit. PMID:27249047

  5. 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...

  6. 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.

  7. 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

  8. Tranexamic acid reduces the blood loss and blood transfusion requirements following peri-acetabular osteotomy.

    Science.gov (United States)

    Wassilew, G I; Perka, C; Janz, V; Krämer, M; Renner, L

    2015-12-01

    We have investigated the effect of using tranexamic acid (TXA) during peri-acetabular osteotomy (PAO) on peri-operative blood loss and blood transfusion requirements. In addition we analysed whether the use of TXA was associated with an increased risk of venous thromboembolism (VTE) following this procedure. A consecutive series of 96 PAOs, performed by a single surgeon, were reviewed. A total of 48 patients received TXA and 48 did not. The TXA group received a continuous infusion of TXA at a rate of 10 mg/kg/h. The primary outcome measure was the requirement for blood transfusion. Secondary outcomes included total blood loss, the decrease in the level of haemoglobin in the blood, the length of hospital stay, and the complications of this treatment. The mean rate of transfusion was significantly lower in the TXA group (62.5% vs 12.5%, p transfusion after PAO significantly, without adverse effects such as an increased rate of VTE.

  9. 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.

  10. Research on Transverse Acetabular Fracture Fixation Using Different Plate Attachment Methods

    Directory of Open Access Journals (Sweden)

    Gediminas Gaidulis

    2015-03-01

    Full Text Available The article deals with the problem of transverse acetabular fracture fixation using different plate attachment methods. A 3D model of pelvis and hip joint structure was created and the design of three different fixation plates using SolidWorks was made. The plates were fixed at distances of 10, 20 and 30 mm from the acetabulum. The model was meshed into finite elements, a static external load of 2500 N was added and the analysis of stress distribution in plates and fracture displacement was performed. The obtained results showed that fracture displacement was quite similar in all fixation methods. However, the maximal stress in the nearest from the acetabulum plate was higher than yield strength. Thus, this placement is not eligible. The plate fixed at a distance of 30 mm from the acetabulum appeared the most suitable because of the smallest and symmetrical stress distribution in the plate.

  11. 髋臼发育不良髋关节置换前髋臼侧的三维测量%Three-dimensional measurement of acetabular side before arthroplasty for acetabular dysplasia

    Institute of Scientific and Technical Information of China (English)

    许杰; 马若凡; 李登; 蔡志清; 李亮平

    2013-01-01

    BACKGROUND:The anatomical strucure of acetabulum is smal and shal ow in adult acetabular dysplasia patients. The large amount of cal us and scar tissues in the acetabulum make it difficult to identify and instal the acetabular cup during arthroplasty. The comprehensive understanding of the acetabulum before arthroplasty is the premise for selecting the appropriate acetabular prosthesis and making the acetabular reconstruction program. OBJECTIVE:To evaluate the application value of three-dimensional reconstruction technique in choosing the size of acetabular cup before total hip arthroplasty for acetabular dysplasia. METHODS:Spiral CT was carried out in the 11 acetabular dysplasia patients who waiting for total hip arthroplasty. The acetabulum was multi-planar reconstructed, and the size of the acetabular cup was determined through digitized acetabular cup template implantation, and then the mathching degree assessment was performed to compare with the actual size. RESULTS AND CONCLUSION:Spiral CT could clearly show the acetabular morphology, and the 71.4%of the acetabular size chosen in the three-dimensional preoperative plan was the same as actual one, the intraclass correlation coefficient was 0.888. The agreement was much higher than that of two-dimensional preoperative plan based on X-ray plain film. For the patients with acetabular dysplasia, the acetabulum became saml er and shal ower, and there were various extents of bone defects in the superior-lateral acetabulum. Three-dimensional multi-planar reconstruction can effectively evaluate the acetabular morphology, and three-dimensional preoperative plan can provide useful information for the choice of implant.%背景:成人髋臼发育不良髋臼小而浅,臼内有大量骨痂和瘢痕组织等都为人工髋关节置换术中真臼的辨认、臼杯的准确安装带来极大困难,关节置换前对髋臼的全面认识是选择合适的髋臼假体和制定个性化髋臼重建方案的前提。目

  12. Acetabular shell deformation as a function of shell stiffness and bone strength.

    Science.gov (United States)

    Dold, Philipp; Pandorf, Thomas; Flohr, Markus; Preuss, Roman; Bone, Martin C; Joyce, Tom J; Holland, James; Deehan, David

    2016-04-01

    Press-fit acetabular shells used for hip replacement rely upon an interference fit with the bone to provide initial stability. This process may result in deformation of the shell. This study aimed to model shell deformation as a process of shell stiffness and bone strength. A cohort of 32 shells with two different wall thicknesses (3 and 4 mm) and 10 different shell sizes (44- to 62-mm outer diameter) were implanted into eight cadavers. Shell deformation was then measured in the cadavers using a previously validated ATOS Triple Scan III optical system. The shell-bone interface was then considered as a spring system according to Hooke's law and from this the force exerted on the shell by the bone was calculated using a combined stiffness consisting of the measured shell stiffness and a calculated bone stiffness. The median radial stiffness for the 3-mm wall thickness was 4192 N/mm (range, 2920-6257 N/mm), while for the 4-mm wall thickness the median was 9633 N/mm (range, 6875-14,341 N/mm). The median deformation was 48 µm (range, 3-187 µm), while the median force was 256 N (range, 26-916 N). No statistically significant correlation was found between shell stiffness and deformation. Deformation was also found to be not fully symmetric (centres 180° apart), with a median angle discrepancy of 11.5° between the two maximum positive points of deformation. Further work is still required to understand how the bone influences acetabular shell deformation.

  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. 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.

  15. 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

  16. 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

  17. 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.)

  18. Absence or interruption of the supra-acetabular line: a subtle plain film indicator of hip pathology

    Energy Technology Data Exchange (ETDEWEB)

    Major, N.M. [Department of Radiology, University of California San Francisco, Box 0628, San Francisco, CA 94143 (United States); Helms, C.A. [Department of Radiology, University of California San Francisco, Box 0628, San Francisco, CA 94143 (United States)

    1996-08-01

    Objective. To show that absence or interruption of the supraacetabular line is a subtle plain film indicator of pathology in the acetabulum. Design. Nineteen hips from 17 patients with known disease processes involving the acetabulum as demonstrated by subsequent magnetic resonance imaging, bone scan or plain film follow-up were evaluated with antero-posterior (AP) plain films of the pelvis. Three additional cases were diagnosed prospectively using interruption of the supra-acetabular line as the criterion for inclusion. Fifty AP plain films of the pelvis in patients without hip pain were examined prospectively to determine normal imaging criteria. Results and conclusions. The normal supra-acetabular line measures 2-3 mm in thickness superiorly and is a thin sclerotic line in the medial aspect. In all 22 hips (with pathology) in this series, the line was interrupted or absent. Loss or interruption of the supra-acetabular line may thus be a subtle pain film indicator of a disease process involving the acetabulum. This plain film sign has not previously been reported. (orig.). With 8 figs., 1 tab.

  19. Reprodutibilidade da classificação de Tile para fraturas do acetábulo Reproducibility of Tile's classification of acetabular fractures

    Directory of Open Access Journals (Sweden)

    Marcos Almeida Matos

    2006-01-01

    Full Text Available Classificar corretamente as fraturas acetabulares é crucial para bom planejamento pré-operatório e para redução cirúrgica eficiente. Entretanto, para cumprir seus objetivos, qualquer sistema de classificação deve ser simples e reprodutível. O objetivo deste artigo é avaliar a reprodutibilidade interobservador da classificação de Tile para fraturas do acetábulo. Foram utilizadas 30 imagens radiográficas de 10 fraturas acetabulares nas incidências de Judet, analisadas por 10 observadores, sendo cinco especialistas em cirurgia de quadril e cinco residentes do terceiro ano de ortopedia. A concordância global obtida foi de 72,44% com Kappa (K = 0,52 (0,48 entre residentes e 0,57 entre especialistas. Conclui-se que a classificação de Tile para fraturas acetabulares apresenta moderada concordância interobservador, não havendo diferença estatisticamente significante entre residentes e especialistas.Properly classifying acetabular fractures is crucial for a good preoperative planning and for an efficient surgical reduction. However, in order to accomplish its objectives, any classification system must be simple and reproducible. The objective of this article is to assess inter-observer reproducibility of Tile’s classification concerning acetabular fractures. Thirty X-ray images of 10 acetabular fractures at Judet planes were used and assessed by 10 observers, being five hip surgery experts and five 3rd-grade orthopaedic residents. The global consistency achieved was 72.44% to Kappa (K = 0.52 (0.48 among resident doctors and 0.57 among experts. It was concluded that the Tile’s classification of acetabular fractures reveals a moderate inter-observer consistency, with no statistically significant difference between resident doctors and experts.

  20. Biomimetic Multispiked Connecting Ti-Alloy Scaffold Prototype for Entirely-Cementless Resurfacing Arthroplasty Endoprostheses—Exemplary Results of Implantation of the Ca-P Surface-Modified Scaffold Prototypes in Animal Model and Osteoblast Culture Evaluation

    Directory of Open Access Journals (Sweden)

    Ryszard Uklejewski

    2016-06-01

    Full Text Available We present here—designed, manufactured, and tested by our research team—the Ti-alloy prototype of the multispiked connecting scaffold (MSC-Scaffold interfacing the components of resurfacing arthroplasty (RA endoprostheses with bone. The spikes of the MSC-Scaffold prototype mimic the interdigitations of the articular subchondral bone, which is the natural biostructure interfacing the articular cartilage with the periarticular trabecular bone. To enhance the osteoinduction/osteointegration potential of the MSC-Scaffold, the attempts to modify its bone contacting surfaces by the process of electrochemical cathodic deposition of Ca-P was performed with further immersion of the MSC-Scaffold prototypes in SBF in order to transform the amorphous calcium-phosphate coating in hydroxyapatite-like (HA-like coating. The pilot experimental study of biointegration of unmodified and Ca-P surface-modified MSC-Scaffold prototypes was conducted in an animal model (swine and in osteoblast cell culture. On the basis of a microscope-histological method the biointegration was proven by the presence of trabeculae in the interspike spaces of the MSC-Scaffold prototype on longitudinal and cross-sections of bone-implant specimens. The percentage of trabeculae in the area between the spikes of specimen containing Ca-P surface modified scaffold prototype observed in microCT reconstructions of the explanted joints was visibly higher than in the case of unmodified MSC-Scaffold prototypes. Significantly higher Alkaline Phosphatase (ALP activity and the cellular proliferation in the case of Ca-P-modified MSC-Scaffold pre-prototypes, in comparison with unmodified pre-prototypes, was found in osteoblast cell cultures. The obtained results of experimental implantation in an animal model and osteoblast cell culture evaluations of Ca-P surface-modified and non-modified biomimetic MSC-Scaffold prototypes for biomimetic entirely-cementless RA endoprostheses indicate the

  1. 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.

  2. Efficient radiologic diagnosis of pelvic and acetabular trauma; Rationelle bildgebende Diagnostik von Becken- und Azetabulumverletzungen

    Energy Technology Data Exchange (ETDEWEB)

    Kreitner, K.F.; Mildenberger, P.; Thelen, M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Radiologie; Rommens, P.M. [Mainz Univ. (Germany). Klinik und Poliklinik fuer Unfallchirurgie

    2000-01-01

    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.) [German] Bei der Klaerung einer Verletzung des Beckens oder des Azetabulums stellen konventionelle Uebersichtsaufnahmen weiterhin die Basis der bildgebenden Diagnostik dar. Art und Umfang werden bestimmt von lokalen Gegebenheiten (z.B. Verfuegbarkeit von CT-Geraeten) sowie vom klinischen Zustand des Patienten. Aufgrund der diagnostischen Ungenauigkeit der konventionellen Roentgendiagnostik gerade im Bereich des stabilitaetsbedeutsamen dorsalen Beckenringes und des Azetabulums schliesst sich beim klinisch stabilen

  3. 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.)

  4. A very rare case with neglected hip dislocation coexisted with posterior acetabular lip fracture

    Directory of Open Access Journals (Sweden)

    Samet Karabulut

    2011-06-01

    Full Text Available Neglected hip dislocation is a rare situation among children. The coexistence of acetabulum fracture is less common. The result of treatment depends on the time of diagnosis. Early treatment is mandatory in such cases. Seven years old female brought to our outpatient clinic with the complaints of right hip pain and walking difficulty. Her parents said that she had fallen from a horse one month ago. X-ray and CT showed a posterior dislocation of her right hip and a fracture on her right posterior acetabular lip. We performed an open reduction via posterior approach. Because the hip was unstable we fixed the femoral head to the acetabulum by a Kirshner wire. Pelvipedal cast was applied after the operation for 6 weeks. After 6 months avascular necrosis (AVN developed on her right femoral head, the range of motion (ROM of the hip was restricted and she had minimal pain on her right hip. J Clin Exp Invest 2011;2(2:228-31

  5. 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

  6. MR-arthrography of the acetabular labrum - radiologic-pathologic correlation in 20 cadaveric hip joints; MR-Arthrographie des Labrum acetabulare - Radiologisch-anatomische Korrelation an 20 Leichenhueften

    Energy Technology Data Exchange (ETDEWEB)

    Brossmann, J.; Steffens, J.C.; Heller, M. [Kiel Univ. (Germany). Klinik fuer Diagnostische Radiologie; Ploetz, G.M.J.; Hassenpflug, J. [Kiel Univ. (Germany). Klinik fuer Orthopadie

    1999-08-01

    Purpose: To investigate frequency of acetabular labral lesions in elderly hip joints, and to determine sensitivity and specificity of MR arthrography (MRa) for the detection of these abnormalities. Materials and Methods: Twenty cadaveric hip joints were examined by MRa. For MRa, 15 ml of a solution of iodinated contrast solution (Solutrast 300) and Gd-DTPA (100:1) were injected under fluoroscopic guidance. MR imaging was performed on a 1.5 TM scanner (Vision, Siemens; FOV 16 cm, matrix 256x256, fat-suppressed 3D-FLASH). Multiplanar image reconstructions were done perpendicular to the acetabulum in the oblique-coronal, oblique-axial, and radial planes. The labral specimens were examined macroscopically. Results: In 12/20 hips (60%), a labral lesion was found on pathologic examination. In 7 specimens, the labrum was partially or completely detached in the weight-bearing superior region. One flap-like variant of the labrum was seen; in 4 hip joints, the labrum was degenerated (one cystic degeneration). Pathologic findings were confirmed by MRa in 8/12 specimens (sensitivity 67%). All degenerated labra were correctly diagnosed on MRa. Three small labral detachments and the flap-like variant were misinterpreted as being normal. There were no false positive findings (specificity 100%). The accuracy was 80%. Labral lesions were seen in 6/8 and in 6/12 of hips with and without osteoarthritis, respectively. Conclusion: MRa is well suited to delineate the acetabular labrum and to diagnose labral abnormalities. Detection of small labral detachments and anatomic variants is difficult and requires some experience. Labral lesions are correlated to osteoarthritis of the hip, but may be frequently seen in the elderly without underlying osteoarthritis. (orig.) [German] Ziel: Feststellung der Haeufigkeit von Laesionen des Labrum acetabulare bei aelteren Hueftgelenkspraeparaten und Untersuchung der Sensitivitaet und Spezifitaet der MR-Arthrographie (MRa) fuer die Darstellung dieser

  7. 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".

  8. Simultaneous Periprosthetic Acetabular Fracture and Contralateral B-Type Compression Injury of the Pelvic Ring: A Case Report of a Rare Injury Combination

    Directory of Open Access Journals (Sweden)

    Sven Märdian

    2013-01-01

    Full Text Available The periprosthetic fracture of the acetabulum is a rare injury, and its management is only sporadically reported in the literature. A few case reports are available which mainly focus on periprosthetic acetabular fractures in the elderly population. In our case, a 32-year-old patient suffered from a periprosthetic acetabular fracture in combination with a pelvic ring injury following a high velocity accident. The fracture morphology allowed a salvage of the prosthesis with an open reduction and internal fixation with a good radiographic and functional outcome one year after trauma.

  9. 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.)

  10. 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.)

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

    Directory of Open Access Journals (Sweden)

    Anica Eschler

    2016-01-01

    Full Text Available 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.

  12. The efficacy of a “double-D-shaped” wire marker for radiographic measurement of acetabular cup orientation and wear

    OpenAIRE

    Derbyshire, Brian; Raut, Videshnandan V.

    2013-01-01

    Historically, wire markers were attached to cemented all-plastic acetabular cups to demarcate the periphery and to measure socket wear. The wire shape was either a semi-circle passing over the pole of the cup, or a circle around the cup equator. More recently, “double-D” shaped markers were introduced with a part-circular aspect passing over the pole and a semi-circular aspect parallel to the equatorial plane. This configuration enabled cup retroversion to be distinguished from anteversion. I...

  13. 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.

  14. 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

  15. Acetabular defect reconstruction with impacted morsellized bone grafts or TCP/HA particles. A study on the mechanical stability of cemented cups in an artificial acetabulum model.

    NARCIS (Netherlands)

    Bolder, S.B.T.; Verdonschot, N.J.J.; Schreurs, B.W.; Buma, P.

    2002-01-01

    In revision surgery of the acetabulum bone defects can be filled with impacted human morsellized bone grafts. Because of a worldwide limited availability of human bone, alternatives are being considered. In this study we compared the initial stability of acetabular cups after reconstructing a cavita

  16. 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.)

  17. 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.

  18. 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.

  19. Cementless anatomical prosthesis for the treatment of 3-part and 4-part proximal humerus fractures: cadaver study and prospective clinical study with minimum 2 years followup

    Directory of Open Access Journals (Sweden)

    Obert Laurent

    2016-01-01

    Full Text Available Introduction: The purpose of this study was to evaluate the functional and radiological outcomes of a cementless, trauma-specific locked stem for 3- and 4-part proximal humeral fractures. Materials and methods: This study consisted of two parts: a cadaver study with 22 shoulders and a multicenter prospective clinical study of 23 fracture patients evaluated at least 2 years after treatment. In the cadaver study, the locked stem (HumelockTM, FX Solutions and its instrumentation were evaluated. In the clinical study, five senior surgeons at four different hospitals performed the surgical procedures. An independent surgeon evaluated the patients using clinical (Constant score, QuickDASH and radiological (X-rays, CT scans outcome measures. Results: The cadaver study allowed us to validate the height landmarks relative to the pectoralis major tendon. In the clinical study, at the review, abduction was 95° (60–160, forward flexion was 108° (70–160, external rotation (elbow at body was 34° (0–55, the QuickDASH was 31 (4.5–59, the overall Constant score was 54 (27–75, and the weighted Constant score was 76 (31.5–109. Discussion: This preliminary study of hemiarthroplasty (HA with a locked stem found results that were at least equivalent to published series. As all patients had at least a 2-year follow-up, integration of the locked stem did not cause any specific complications. These results suggest that it is possible to avoid using cement when hemiarthroplasty is performed for the humeral stem. This implant makes height adjustment and transosseous suturing of the tuberosities more reproducible.

  20. 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

  1. 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

  2. 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...

  3. 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.)

  4. 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.)

  5. 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.)

  6. 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.].

  7. 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

  8. O uso de enxerto homólogo na revisão de artroplastias do quadril com cimentação do componente acetabular Use of homologous graft in hip arthroplasty reviews with acetabular component cementation

    Directory of Open Access Journals (Sweden)

    Fábio Stuchi Devito

    2006-01-01

    Full Text Available A artroplastia total do quadril representa um grande avanço no tratamento das enfermidades ortopédicas que acometem o quadril. A soltura asséptica desta prótese pode causar lesões e perdas ósseas, representando um grande desafio para a reconstrução cirúrgica destas artroplastias. Uma das alternativas para a reconstrução é o uso do enxerto ósseo de banco de ossos, podendo este ser usado em bloco ou na forma picada. Este estudo, baseado em uma revisão da literatura sobre enxertos ósseos, teve como objetivo uma análise quanto à reconstrução com enxertos em bloco e picado e sua integração. O enxerto picado mostrou melhores resultados quanto à integração quando se consegue estabilidade da reconstrução. Quando não conseguimos uma boa estabilidade, o enxerto em bloco associado aos anéis de reforço sobressai como a melhor opção.Hip total arthroplasty represents a breakthrough in the treatment of orthopaedic illnesses affecting the hip. The aseptic loosening of this prosthesis may cause injuries and bone losses, representing a great challenge for the surgical reconstruction of those arthroplasties. One alternative to reconstruction is the use of bone graft sourced by bone bases, which may be used as a block or in pieces. This study, based on a literature review addressing bone grafts, had as an objective to analyze reconstruction with grafts in blocks and in pieces and its union. The graft in pieces showed better results concerning union when reconstruction stability is achieved. When a good stability cannot be achieved, the graft in block combined with reinforcement rings is highlighted as the best option.

  9. 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

  10. Gait analysis after total knee arthroplasty with cemented versus cementless type%骨水泥型与非骨水泥型全膝关节置换后的步态差异

    Institute of Scientific and Technical Information of China (English)

    张旻; 江澜; 沈晓艳

    2011-01-01

    背景:全膝关节置换已经被证明是一种有效治疗膝骨性关节炎的方法,但是不同类型的全膝关节置换假体固定方式术后所产生的膝关节下肢生物力学差异至今仍不明确.目的:通过三维步态分析骨水泥固定和非骨水泥固定两种不同的全膝关节置换术后患者的膝关节生物力学差异.方法:分别选取骨水泥型全膝关节置换以及非骨水泥型全膝关节置换患者各16例,通过测力台以及三维步态分析系统比较2组患者术前以及术后3个月的膝关节生物力学变化并进行对比.结果与结论:与手术前相比两组患者术后步速及步长均明显增加,支撑相在整个步态周期中的百分比明显减小, 膝关节屈在支撑相及摆动相中最大屈曲角度均明显增加,膝关节外翻角度增加.两种患者术后膝关节内翻角度以及膝关节内收力矩均明显减小.提示,骨水泥型与非骨水泥型全膝关节置换术均能有效改善膝骨性关节炎患者的步行能力以及下肢关节功能,两者间未见明显生物力学差异.%BACKGROUND: Total knee arthroplasty (TKA) has been proved to be a very effective method for patients with knee osteoarthritis. But the biomedical changes at knee joint between two different types of TKA (cemented and cementless) after operation remain not clear.OBJECTIVE: To explore the different biomechanical changes between the cemented and cementless TKA through three-dimensional gait analysis.METHODS: A total of 16 knee osteoarthritis patients treated with cemented TKA and 16 with cementless TKA were included.Force plates and three-dimensional gait analysis system were used to compare differences in biomechanics before and 3 months after operations.RESULTS AND CONCLUSION: Both groups showed significant increased walking speed and stride length, but decreased percentage of stance phase in gait cycle after operation, significant increased knee flexion angle in stance phase and swing

  11. Acetabular trabecular direction between different species%不同物种髋臼的骨小梁方向*☆

    Institute of Scientific and Technical Information of China (English)

    孙剑伟; 颜冰珊; 尹望平; 张春才

    2013-01-01

      BACKGROUND: Some studies have shown that the morphological structure of bone is closely related with the stress environment. But the human walking upright movement may affect the direction of the acetabular trabecular bone. OBJECTIVE: To observe the differences of acetabular bone direction between different species. METHODS: Hip bones of human and rhesus monkey selected from Department of Anatomy, Second Military Medical University and the Shandong University School of Life Science were scanned by X-ray under the same conditions of shooting. The images were imported into Imagine pro plus 6.0 and transferred by fast fourier transform, then obtained the spectrum value of 0°-180° to calculate the number of trabeculae in a certain direction. RESULTS AND CONCLUSION: The human had highest spectrum value in 0° and 90° which were in accordance with Ilioischial bundle and sacropubic bundle. Rhesus monkeys distributed dispersedly and there was no obvious peak. The human trabecular in acetabular region mainly distributed along 90°-180° which were in accordance with Ilioischial bundle and sacropubic bundle, this indicated that there was relationship between Ilioischial bundle and human walking pattern.%  背景:有研究认为骨的形态结构与其所处的应力环境密切相关。由于人类直立行走的运动方式,可能会影响髋臼骨小梁的方向。目的:观察不同物种髋臼骨小梁方向的差异。方法:X射线观察由解放军第二军医大学解剖教研室和山东大学生命科学院提供的成人双侧髋骨干燥标本和成年恒河猴髋骨标本,将采集到的图像输入 Imagine pro plus 6.0,经快速傅里叶变换后,得出0°-180°的频谱值,计量不同的角度骨小梁的数量。结果与结论:人类髋骨在0°及90°频谱值最大,与骶耻束与髂坐束的方向符合。而恒河猴髋骨的频谱值分布较为弥散,没有明显的峰值。说明人类

  12. 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.

  13. Classification and treatment of acetabular fractures%髋臼骨折的分类与治疗策略

    Institute of Scientific and Technical Information of China (English)

    曾令源

    2012-01-01

    Fracture of acetabulum is mostly caused by high energy trauma, which exists as a whole or a part of palvic fracture. Acetabulum is characterized by complex anatomical relationships irregular bone structures, which leads to the difficulties in surgery. The surgical approach is found to be closely related to the classification of cetabular fractures. And several factors are proved to influence the clinical efficacy. In this review, we present the progress on the classification and treatment of acetabular fractures.%髋臼为不规则骨,为丰厚软组织包裹,多为挤压或传导受力导致骨折,髋臼骨折与髋关节活动大有很大关联.髋臼的解剖关系复杂、骨性结构不规则,因而手术难度大.髋臼骨折的分类与手术入路的选择密切相关,此外,还有一些因素也会影响疗效.本文主要讨论髋臼骨折的分类及相应治疗的一些内容.

  14. 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.)

  15. Comparison of wear of ultra-high molecular weight polyethylene acetabular cups against surface-engineered femoral heads.

    Science.gov (United States)

    Galvin, A; Brockett, C; Williams, S; Hatto, P; Burton, A; Isaac, G; Stone, M; Ingham, E; Fisher, J

    2008-10-01

    Alumina ceramic heads have been previously shown to reduce polyethylene wear in comparison to cobalt chrome (CoCr) heads in artificial hip joints. However, there are concerns about the brittle nature of ceramics. It is therefore of interest to investigate ceramic-like coatings on metallic heads. The aim of this study was to compare the friction and wear of ultra-high molecular weight polyethylene (UHMWPE) against alumina ceramic, CoCr, and surface-engineered ceramic-like coatings in a friction simulator and a hip joint simulator. All femoral heads tested were 28 mm diameter and included: Biolox Forte alumina, CoCr, arc evaporative physical vapour deposition (AEPVD) chromium nitride (CrN) coated CoCr, plasma-assisted chemical vapour deposition (PACVD) amorphous diamond-like carbon (aDLC) coated CoCr, sputter CrN coated CoCr, reactive gas controlled arc (RGCA) AEPVD titanium nitride (TiN) coated CoCr, and Graphit-iC coated CoCr. These were articulated against UHMWPE acetabular cups in a friction simulator and a hip joint simulator. Alumina and CoCr gave the lowest wear volumes whereas the sputter coated CrN gave the highest. Alumina also had the lowest friction factor. There was an association between surface parameters and wear. This study indicates that surface topography of surface-engineered femoral heads is more important than friction and wettability in controlling UHMWPE wear.

  16. 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...

  17. 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...

  18. 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

  19. Utilization of virtual reality technology in acetabular surgery%虚拟现实技术在髋臼手术中的应用

    Institute of Scientific and Technical Information of China (English)

    王玫; 张月东; 张兰华

    2011-01-01

    BACKGROUND: At present, abroad has carried out some research and practice on the medical virtual reality technology,especially in a virtual medical simulation training and other aspects of surgery, but it does not fully meet the needs of clinical orthopedic surgery. The acetabular fractures are difficult to treat because of its com plexity. Clinicians select appropriate treatment options and surgical approaches according to imaging studies, which are difficult to accurately determine the spatial three-dimensional relationship.OBJECTIVE: To review the application of virtual reality technology in acetabular surgery.METHODS: CNKI, PubMed, Wanfang and VIP databases were searched for papers addressing application of virtual reality in acetabular surgery using key words of "finite element model, acetabular fracture, and virtual surgery" both in English and Chinese.The repetitive studies or papers with blur parameter were removed.RESULTS AND CONCLUSION: Totally 115 documents were initial searched by computer, and 32 papers were included in this review. Acetabular virtual surgery system can analyze the complex of acetabulum and simulate the actual situation, thus, provides a 3-dimensional virtual procedure for clinical operations. A virtual platform can provide guidance for making preoperative plan,which has good prospect in medical surgery teaching and simulation training.%背景:目前国外已经对医学虚拟现实,尤其是在虚拟医学手术仿真训练等方面都进行了一定的研究和实践,但并不能完全适应骨科手术的临床需要.而髋臼骨折因其复杂性治疗困难,临床医师选择适当治疗方案和手术入路的主要依据来源于影像学检查,常难以准确判断空间立体关系.目的:综合分析虚拟现实技术在髋臼手术中的应用情况.方法:作者于2010-10通过互联网计算机检索了中国期刊全文数据库(CNKI)、PubMed数据库、万方数据库及维普数据库1980-01/2010-10以中文或英文

  20. 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

  1. Bilateral central acetabular fracture dislocation in a young patient due to seizure activity:a case report and review of the literature

    Institute of Scientific and Technical Information of China (English)

    Umesh Kumar Meena; Devi Sahai Meena; Prateek Behera; Om Singh Meel

    2014-01-01

    Various musculoskeletal injuries are well known complications of epilepsy either because of direct trauma or because of unbalanced forceful muscle contraction. We report a case of non-traumatic bilateral central acetabular fracture dislocation due to seizure activity induced by neurocysticercosis of the brain, which was managed conservatively and obtained reasonable good outcome. This case highlights the importance of proper evaluation in young non-osteoporotic patients who have experienced an epileptic attack without any previous history. It is also imperative to mention that these patients should be thoroughly examined neurologically to find out the exact etiology and should be treated accordingly to prevent future seizure activity.

  2. 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.

  3. 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.)

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

    Directory of Open Access Journals (Sweden)

    Cyrus Brodén

    2016-01-01

    Full Text Available 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.

  5. 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

  6. The efficacy of a "double-D-shaped" wire marker for radiographic measurement of acetabular cup orientation and wear.

    Science.gov (United States)

    Derbyshire, Brian; Raut, Videshnandan V

    2013-01-01

    Historically, wire markers were attached to cemented all-plastic acetabular cups to demarcate the periphery and to measure socket wear. The wire shape was either a semi-circle passing over the pole of the cup, or a circle around the cup equator. More recently, "double-D" shaped markers were introduced with a part-circular aspect passing over the pole and a semi-circular aspect parallel to the equatorial plane. This configuration enabled cup retroversion to be distinguished from anteversion. In this study, the accuracy of radiographic measurement of cup orientation and wear was assessed for cups with "double-D" and circular markers. Each cup was attached to a measurement jig which could vary the anteversion/retroversion and internal/external rotation of the cup. A metal femoral head was fixed within the socket and radiographic images were created for all combinations of cup orientation settings. The images were measured using software with automatic edge detection, and cup orientation and zero-wear accuracies were determined for each setting. The median error for cup version measurements was similar for both types of wire marker (0.2° double-D marker, -0.24° circular marker), but measurements of the circular marker were more repeatable. The median inclination errors were 2.05° (double-D marker) and 0.23° (circular marker). The median overall "zero wear" errors were 0.19 mm (double-D marker) and 0.03 mm (circular marker). Measurements of the circular wire marker were much more repeatable.

  7. 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

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

    Science.gov (United States)

    Brodén, Cyrus; Olivecrona, Henrik; Maguire, Gerald Q; Noz, Marilyn E; Zeleznik, Michael P; Sköldenberg, Olof

    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

  9. 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

  10. FE analysis of the position of acetabular prosthesis in total hip arthroplasty%有限元分析全髋置换术髋臼假体位置影响

    Institute of Scientific and Technical Information of China (English)

    廖胜辉; 李玲芝

    2011-01-01

    Objective To investigate the effects of acetabular prosthesis position on the reconstructed hip funcion after the total hip arthroplasty by 3D finite element analysis.Methods Using a special designed biomechanical semi-automatic mesh generator, a high quality specific 3D finite element model of the hip bone was generated from the CT scan data of a patient with hip joint dysplasia.And then the acetabular prosthesis was integrated at the true acetabular position, compared with penetration position, and the position above the true acetabular, to investigate the position infuence of acetabular prosthesis for the total hip arthroplasty.Finally,all models were simulated under same loading conditions.Results (1) The model with acetabular prosthesis placed at the true acetabular position provided the optimal silumation result, with smallest principal stresses and sheer stresses; (2) The model with penetration position resulted some bigger stresses than the true acetabular position; (3) The model with position above the true acetabular resulted much bigger stresses.Conclusions The acetabular prosthesis for the total hip arthroplasty should be placed at the true acetabular position as possible, to provide the optimal stresses distribution and functinal repair.%目的 利用三维有限元仿真方法研究全髋关节置换术后假体位置对髋关节功能的影响,便于指导手术操作,并为临床提供评价标准.方法 采用专门的生物力学有限元网格划分器从髋关节发育不良的CT扫描数据建立高度仿真的个性化髋骨三维有限元模型,并采用直接在真臼位置重建安放臼杯假体,将髋臼内壁打磨穿透进行内移安放,和髋臼上位方重建进行上移高位安放3种常见的临床手术方案,模拟臼杯假体位置对全髋关节置换术的影响.结果 (1)直接在真臼位置安放的效果是最好的,出现应力集中和大剪切应力的可能性最小;(2)穿透内移安放的模拟应

  11. 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

  12. 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.

  13. 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

  14. 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.)

  15. Current status of noncemented hip implants.

    Science.gov (United States)

    Harris, W H

    1987-01-01

    Recently the operative techniques, instrumentation, design, and material properties of bony ingrowth total hip replacement have been greatly improved. I prefer a hemispherical acetabular component fixed with screws going through the metal shell. The titanium mesh allows microinterlock with new bone, and macrointerlock is obtained by adding bone graft into the unused screw holes. The femoral component, made of Tivanium with titanium mesh attached to it by a new process called diffusion bonding, retains superalloy fatigue strength characteristics. An intimate press fit is assured by the specific operative technique, and both the fiber mesh and the collar provide proximal stress transfer. The design affords a nondestructive method for removal if necessary. The short-term clinical results are promising; most patients function as well as with cemented total hip replacement. The incidence of thigh pain has been significantly reduced since prior reports of cementless total hip replacement; however, a few patients still have thigh pain. The results in revision surgery are also promising, but as in cemented total hip replacement, the functional capacity of revision cases is usually lower than primary cases. There is an increased capacity to correct complex and difficult acetabular problems with this acetabular component. Obviously, long-term data are needed to establish the behavior of these implants over the immediate and long term.

  16. Revision Total Hip Arthroplasty with Retained Acetabular Component%保留臼杯的全髋关节翻修术

    Institute of Scientific and Technical Information of China (English)

    Muyibat A.Adelani; Nathan A.Mall; Humaa Nyazee; John C.Clohisy; Robert L.Barrack; Ryan M.Nunley; 肖建林; 左建林; 高忠礼

    2014-01-01

    背景:无菌性松动和骨溶解通常限制全髋关节假体的生存率.保留固定良好的臼杯,而不是全臼杯的翻修,具有多种优点,但其临床效果与假体生存率尚存疑虑.我们采取这种有限的翻修,分析了臼杯的位置、聚乙烯类型、衬垫植入技术、股骨头大小和同时进行整个股骨柄翻修(相对只更换股骨头和衬垫而言)或者植骨对假体生存率的中长期影响.方法:100例患者(100髋)骨溶解,聚乙烯磨损或股骨假体松动而进行保留臼杯的全髋关节翻修术.在翻修前的放射线片上测量臼杯的外展角和前倾角并按照预先确定的安全区(外展范围,35°-55°;前倾范围,5°~25°)进行分类.手术记录也被回顾分析,包括股骨头大小、聚乙烯衬垫类型(传统或高交联)、衬垫植入技术(利用现有的锁定机制或骨水泥固定)、患者是否进行了全股骨柄的翻修和术中植骨.随访的结果包括Harris评分、UCLA评分、术后不稳的发生次数和是否需要再次翻修.结果:术后平均6.6年(范围,2~14年)Harris评分和UCLA评分相比术前均具有显著改善(P< 0.0001比P< 0.01).总体而言,失败率为13%,此外,6%的患者术后出现不稳,外展角不在臼杯正常安全区的患者具有较高的失败率(P=0.048).翻修时使用传统聚乙烯衬垫与使用高交联聚乙烯衬垫相比,再次翻修率增加(P=0.025).结论:对于术前臼杯位置良好固定可靠的患者,保留臼杯的翻修手术会获得良好的临床效果,臼杯外展角不在安全区内的失败风险很高,使用传统聚乙烯衬垫也是如此.

  17. 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

  18. 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.

  19. “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

  20. 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-...

  1. 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

  2. 改良 Stoppa 入路治疗骨盆髋臼骨折%Modified Stoppa approach in the treatment of pelvic and acetabular fractures

    Institute of Scientific and Technical Information of China (English)

    王树金; 孔丹辉; 吴树华; 王遥伟; 陈志军; 束伟平

    2015-01-01

    Objective To evaluate the modified Stoppa approach in the treatment of pelvic and acetabular fractures. Method Applica-tion of modified Stoppa approach for the treatment of pelvic and acetabular fractures in 13 cases. 8 cases of pelvic fracture according to Tile classification:type B2 2 cases,type C1 - 1 1 case,type C1 - 2 2 cases,type C1 - 3 1 case,type C2 in 3 cases,2 cases with pubic symphysis, bilateral pubic rami fractures in 3 cases,1 case of sacral iliac joint dislocation,sacral fracture in 1 case;type Letournel 8 cases of acetabular fractures:anterior column fracture in 2 cases,anterior column + Half transverse fracture in 2 cases,1 case of transverse fracture,double column fractures in 3 cases,2 cases with dislocation of hip joint. Results 16 cases were followed up,time 8 ~ 24 months,average 12 months,all fractures were healed,the healing time ranged from 3 to 5. 5 months,average 3. 9 months. 1 case of double column fracture hip flexion slightly restricted,1 case of dislocation of sacroiliac joint mild claudication,no screws loosening,fracture,without loss of reduction;1 case of incision infection,healed after dressing change. Results After operation,according to the Matta method,10 cases were excellent and 3 cases were good,The excellent and good rate was 81. 25%. Conclusion The modified Stoppa approach in the treatment of pelvic and ac-etabular fractures with a good clinical application value,which can be fully exposed iliac wing,anterior column,anterior and superior ramus of pubis,especially in the anterior column of the acetabulum or anterior displaced fracture,transverse fracture,T fracture,double column fractures or associated with the transverse fracture of the anterior column fractures,pelvic fracture and femoral head center dislocation anteri-or wall fractures or with pubic symphysis injury,superior medial sided body displaced acetabular fractures,it is an excellent choice in surgi-cal treatment of pelvic and acetabular fractures

  3. 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

  4. 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

  5. Acetabular lateral reconstruction after total hip arthroplasty:understanding and application of core technology%人工髋关节翻修髋臼侧重建:对技术核心的认识及应用

    Institute of Scientific and Technical Information of China (English)

    张文贤; 范有福; 王小燕; 吕江宏

    2014-01-01

    BACKGROUND:After the initial hip replacement, aseptic or infective loosening and subsidence of the prosthesis, acetabular wear, pain, osteolysis and other factors may lead to the loss of prosthesis stability and loss of joint function, which are the common cause of hip arthroplasty. Among the hip arthroplasty, acetabular lateral reconstruction is essential and largely determines the success or failure of revision surgery. OBJECTIVE:To explore the present situation of reconstructing acetabulum after total hip arthroplasty. METHODS:A computer-based online search of PubMed database (http://www.ncbi.nlm.nih.gov/PubMed) between January 1998 and March 2014, and CNKI database (http://www.cnki.net/) from January 2003 to March 2014 was undertaken for the articles about reconstructing acetabulum after total hip arthroplasty. The key words were“artificial joint, reconstruction, acetabular lateral reconstruction, current situation”in Chinese and“reconstructed acetabulum, total hip arthroplasty”in English. Article about hip reconstruction, acetabyular reconstruction, bone defect reconstruction, prosthesis choice and reconstruction, and soft tissue balance were also selected. Repetitive researches were excluded. RESULTS AND CONCLUSION:According to inclusion criteria, 26 articles were involved in this study. A perfect acetabular revision should achieve the fol owing goals:stabilize acetabular prosthesis after acetabular revision;recover hip rotation center and biomechanical properties;repair acetabular bone defects and increase hip bone. Adequate preparation before surgery is an important prerequisite for the success of surgery and good results, aseptic and septic loosening or subsidence of the prosthesis, as wel as acetabular wear and tear are common causes of hip revision. Intraoperative reconstruction of acetabular anteversion and camber angles, acetabular rotation center reconstruction, reconstruction of acetabular bone defects, selection of reconstruction of

  6. 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

  7. 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...

  8. 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

  9. 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

  10. 前后联合入路治疗复杂髋臼骨折的疗效观察%Before or after Consociation Go into the Road Cure the Curative Effect Observation of Complicated Bone Fracture of Acetabular

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

      目的探讨前后联合入路治疗复杂髋臼骨折的临床疗效。方法回顾性分析2006年1月至2012年1月期间我院采用经髂腹股沟入路联合K-L入路手术治疗32例复杂髋臼骨折患者的临床资料。结果全部32例患者均顺利完成手术,无1例术中死亡,手术时间为(2.9±0.7)h,术中失血量为(820±190)mL,全部患者均获得1~3年随访,出现异位骨化者3例,髋臼复位满意率为93.8%,髋关节功能总优良率为90.6%。结论前后联合入路治疗复杂髋臼骨折疗效显著,具有暴露充分、复位方便、固定可靠、功能恢复好等优点,值得临床推广应用。% Objective Inquire into associately going into the clinical curative effect that the road cures complicated bone fracture of Acetabular before or after. Methods Look back sex to analyze January, 2006~January, 2012 period I hospital adoption through Ka stomach the ditch go into road consociation K-L go into the road surgical operation cure the bone fracture sufferer's clinical data of 32 complicated Acetabular. Results All 32 sufferers complete surgical operation smoothly and have no to die in a Shu, surgical operation time BE(2.9±0.7) h, lose the amount of blood as ml(820±190) in the Shu, all sufferers acquire for 1~3 years with visit, appear difference the bone turn 3, the Acetabular resets a satisfaction to lead to 93.8%, Acetabular joint the function Be always good to lead to 90.6%.Conclusion Before or after consociation go into the road cure complicated Acetabular bone fracture curative effect to show Zhao and have expose well and reset convenience, fix credibility, the function resume a good etc. advantage, worth clinical expansion application.

  11. In vivo implant fixation of carbon fiber-reinforced PEEK hip prostheses in an ovine model.

    Science.gov (United States)

    Nakahara, Ichiro; Takao, Masaki; Bandoh, Shunichi; Bertollo, Nicky; Walsh, William R; Sugano, Nobuhiko

    2013-03-01

    Carbon fiber-reinforced polyetheretherketone (CFR/PEEK) is theoretically suitable as a material for use in hip prostheses, offering excellent biocompatibility, mechanical properties, and the absence of metal ions. To evaluate in vivo fixation methods of CFR/PEEK hip prostheses in bone, we examined radiographic and histological results for cementless or cemented CFR/PEEK hip prostheses in an ovine model with implantation up to 52 weeks. CFR/PEEK cups and stems with rough-textured surfaces plus hydroxyapatite (HA) coatings for cementless fixation and CFR/PEEK cups and stems without HA coating for cement fixation were manufactured based on ovine computed tomography (CT) data. Unilateral total hip arthroplasty was performed using cementless or cemented CFR/PEEK hip prostheses. Five cementless cups and stems and six cemented cups and stems were evaluated. On the femoral side, all cementless stems demonstrated bony ongrowth fixation and all cemented stems demonstrated stable fixation without any gaps at both the bone-cement and cement-stem interfaces. All cementless cases and four of the six cemented cases showed minimal stress shielding. On the acetabular side, two of the five cementless cups demonstrated bony ongrowth fixation. Our results suggest that both cementless and cemented CFR/PEEK stems work well for fixation. Cup fixation may be difficult for both cementless and cemented types in this ovine model, but bone ongrowth fixation on the cup was first seen in two cementless cases. Cementless fixation can be achieved using HA-coated CFR/PEEK implants, even under load-bearing conditions.

  12. 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.

  13. Phosphocalcium ceramics are efficient in the management of severe acetabular loss in revision hip arthroplasties. A 22 cases long-term follow-up study.

    Science.gov (United States)

    Schwartz, C; Vautrin, M

    2015-02-01

    Management of bone loss in revision total hip replacement remains a challenge. To eliminate any immunological or infectious problem and so to try to improve the long-term results obtained with allografts, the authors used synthetic ceramics as bone substitutes since 1995. We reviewed 13 of the patients of our study, we previously reported in 2005 (Schwartz and Bordei in Eur J Orthop Surg Traumatol 15: 191 2005), which was a prospective cohort of thirty-two cases of acetabular revision reconstruction, with a mean follow-up of 14.4 years yet (from 9 to 16 years). Clinical results were assessed according to Oxford scale and Postel and Merle d'Aubigne (PMA) scale. Since 2005, no specific complications were noted. The average PMA functional hip score was 14.9 (vs. 9.2 before revision) at follow-up over 9 years. Nine patients still alive in 2013 were seen again by a surgeon, which was not the operator, with a mean follow-up of 15.3 years: Their Oxford average score was 40.3. Radiological assessment affirmed a good integration of the substitutes in bone without any edging in all cases. A progressive invasion of the ceramics by bone can be seen on the X-ray. We conclude that about 15 years of average delay, which is a significant follow-up in orthopedic surgery, the outcomes without specific complications are satisfactory and allow one to go with these materials in total hip revision surgery.

  14. Backside Wear Analysis of Retrieved Acetabular Liners with a Press-Fit Locking Mechanism in Comparison to Wear Simulation In Vitro

    Directory of Open Access Journals (Sweden)

    Ana Laura Puente Reyna

    2016-01-01

    Full Text Available Backside wear due to micromotion and poor conformity between the liner and its titanium alloy shell may contribute to the high rates of retroacetabular osteolysis and consequent aseptic loosening. The purpose of our study was to understand the wear process on the backside of polyethylene liners from two acetabular cup systems, whose locking mechanism is based on a press-fit cone in combination with a rough titanium conical inner surface on the fixation area. A direct comparison between in vitro wear simulator tests (equivalent to 3 years of use and retrieved liners (average 13.1 months in situ was done in order to evaluate the backside wear characteristics and behavior of these systems. Similar wear scores between in vitro tested and retrieved liners were observed. The results showed that this locking mechanism did not significantly produce wear marks at the backside of the polyethylene liners due to micromotion. In all the analyzed liners, the most common wear modes observed were small scratches at the cranial fixation zone directly below the rough titanium inner surface of the shell. It was concluded that most of the wear marks were produced during the insertion and removal of the liner, rather than during its time in situ.

  15. 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

  16. 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

  17. 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

  18. 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.)

  19. 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

  20. 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.

  1. 带翼型髋臼加强杯在重建髋臼肿瘤切除后骨缺损中的应用%UTILIZATION OF REINFORCED ACETABULAR CAGES WITH CAUDAL FLANGE IN RECONSTRUCTING PELVIC DEFECT AFTER ACETABULAR TUMOR RESECTION

    Institute of Scientific and Technical Information of China (English)

    李大森; 郭卫; 杨荣利; 汤小东; 曲华毅

    2011-01-01

    Objective To evaluate the surgical procedure of reinforced acetabular cage with caudal flange in reconstruction of pelvic defect after acetabular tumor resection. Methods Between June 2003 and December 2009, 25 patients with Harrington class III pelvic defect underwent reconstruction with a reinforced acetabular cage with caudal flange and total hip arthroplasty (THA). There were 13 males and 12 females with an average age of 51.2 years (range, 13-73 years). The main clinical manifestations included hip pain and buttock pain, with a median disease duration of 6 months (range, 1-96 months). Pathological findings showed 18 cases of metastasis, 3 cases of multiple myeloma, 1 case of non-Hodgkin's lymphoma, 1 case of grade I chondrosarcoma, 1 case of giant cell tumor, and 1 case of chondroblastoma. For the patient with chondroblastoma, THA with LINK RIBBED system was used. An artificial total hip system made in China was used in 6 patients and LINK SP II system was used in the other 18 patients. Results No patients died perioperatively. Deep infection and hip dislocations occurred inI and 2 patients, respectively. At last follow-up, 8 of 18 patients with metastasis died of cancer and the average survival time wasII months. The other 10 who were alive were followed up 15 months on average. One patient with multiple myeloma died of pulmonary infection at 21 months after operation and the other 2 with multiple myeloma and 1 with lymphoma were alive with an average follow-up of 17 months. The patient with grade I chondrosarcoma and patient with chondroblastoma were followed up 58 and 12 months, respectively, without recurrence. Recurrence occurred in the patient with giant cell tumor at 19 months after operation. Loosening of implant occurred in 3 patients because of local tumor recurrence. For the 23 patients at 6 months after operation, the mean Musculoskeletal Tumor Society (MSTS) 93 score was 81% (range, 57%-93%). Conclusion Reinforced acetabular cage with caudal

  2. 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

  3. Bernese periacetabular osteotomy for the treatment of acetabular dysplasia%Bernese髋臼周围截骨治疗髋臼发育不良★

    Institute of Scientific and Technical Information of China (English)

    宋立明

    2013-01-01

      背景:改变髋臼朝向是纠正髋臼发育不良的最好方法,而Bernese髋臼周围截骨是当前最常应用也是最成功的治疗方法之一。目的:总结分析Bernese髋臼周围截骨的适应证及技术和影响效果的因素,以期更好的应用于临床。方法:使用“Bernese osteotomy,Ganz osteotomy,periacetabular ostetomy”作为关键词,采用计算机检索PubMed、Elsevier和Springer数据库中2012年12月以前的相关文章。纳入与Bernese髋臼周围截骨治疗在髋臼发育不良患者中临床应用的相关文献;排除重复研究和Meta分析类文章。重点对Bernese髋臼周围截骨治疗的适应证及技术和治疗效果的影响因素进行综合分析。结果与结论:计算机初检得到483篇文献,根据纳入排除标准,对其中43篇文献进行分析。Bernese截骨术是采用改良的Smith-Peterson入路在髋臼周围进行多边形截骨。虽然手术技术逐渐改进,但是主要截骨步骤一直保持不变,只是改良了软组织松解方法。影响Bernese髋臼周围截骨治疗后效果的直接因素是影像学上髋关节退变和发育不良的严重程度。将来随着对髋关节畸形理解的深入,Bernese髋臼周围截骨治疗的指征、技术方式也将得到发展。%BACKGROUND:Changing the acetabular orientation is the best method for the treatment of acetabular dysplasia, and Bernese periacetabular osteotomy is one of the most commonly used and successful treatment methods. OBJECTIVE:To review and analyze the operation indication, surgical technique and influencing factors of Bernese periacetabular osteotomy for better clinical application. METHODS:The PubMed database, Elsevier database and Springer database were retrieved for related articles published before December 2012 with the key words of“Bernese osteotomy, Ganz osteotomy, periacetabular ostetomy”. The articles that related to the clinical application of Bernese

  4. Variability and component composition

    NARCIS (Netherlands)

    Storm, T. van der

    2004-01-01

    In component-based product populations, feature models have to be described at the component level to be able to benefit from a product family approach. As a consequence, composition of components becomes very complex. We describe how component-level variability can be managed in the face of compone

  5. Stemless humeral component in reverse shoulder prosthesis in patient with Parkinson’s disease: a case report

    Science.gov (United States)

    Giannotti, Stefano; Bottai, Vanna; Dell’Osso, Giacomo; Bugelli, Giulia; Guido, Giulio

    2015-01-01

    Summary Introduction In patients with Parkinson’s disease falling is very common and for this reason, the prosthetic surgical indication in shoulder is reserved for special cases. PD has been linked to several interrelated factors that may contribute to failure of shoulder arthroplasty. Case presentation A 65-year-old woman with PD, severe pain, recurrent bursitis, swelling and functional limitation to all movements in left shoulder presented to our attention. Radiographic and CT exams show cuff-tear arthropathy. The patient was submitted to implantation of a Reverse Shoulder Comprehensive Nano cementless modular system (Biomet®, Warsaw, IN, USA) with anterosuperior surgical approach. We chose this kind of solution of stemless humeral component after bone mineral consideration. Discussion Reverse shoulder arthroplasty represents an option in the management of glenohumeral arthritis. Poor functional results of RTSA in patients with PD have been attributed to increased muscle tone, severity of tremor and an increased mortality rate. In general, post operative complications related to the humeral component are dominated by fractures (between 1 and 3%): in patients with PD this percentage is higher because of falls often occur. With a stemless implant revisions can be performed easily. Overall, the anterosuperior surgical exposure gives a low risk of postoperative instability. Conclusion In selected cases of patients with PD, after carefully analysis of bone quality, the use of a stemless component is of benefit in the possible revision cases for periprosthetic fractures and the use of an anterosuperior exposure reduces the percentage of instability. The results obtained about the pain relief are excellent in contrast with functional outcomes that remain poor. PMID:26136798

  6. Mechanisms of plastic deformation in highly cross-linked UHMWPE for total hip components--the molecular physics viewpoint.

    Science.gov (United States)

    Takahashi, Yasuhito; Shishido, Takaaki; Yamamoto, Kengo; Masaoka, Toshinori; Kubo, Kosuke; Tateiwa, Toshiyuki; Pezzotti, Giuseppe

    2015-02-01

    Plastic deformation is an unavoidable event in biomedical polymeric implants for load-bearing application during long-term in-vivo service life, which involves a mass transfer process, irreversible chain motion, and molecular reorganization. Deformation-induced microstructural alterations greatly affect mechanical properties and durability of implant devices. The present research focused on evaluating, from a molecular physics viewpoint, the impact of externally applied strain (or stress) in ultra-high molecular weight polyethylene (UHMWPE) prostheses, subjected to radiation cross-linking and subsequent remelting for application in total hip arthroplasty (THA). Two different types of commercial acetabular liners, which belong to the first-generation highly cross-linked UHMWPE (HXLPE), were investigated by means of confocal/polarized Raman microprobe spectroscopy. The amount of crystalline region and the spatial distribution of molecular chain orientation were quantitatively analyzed according to a combined theory including Raman selection rules for the polyethylene orthorhombic structure and the orientation distribution function (ODF) statistical approach. The structurally important finding was that pronounced recrystallization and molecular reorientation increasingly appeared in the near-surface regions of HXLPE liners with increasing the amount of plastic (compressive) deformation stored in the microstructure. Such molecular rearrangements, occurred in response to external strains, locally increase surface cross-shear (CS) stresses, which in turn trigger microscopic wear processes in HXLPE acetabular liners. Thus, on the basis of the results obtained at the molecular scale, we emphasize here the importance of minimizing the development of irrecoverable deformation strain in order to retain the pristine and intrinsically high wear performance of HXLPE components.

  7. Clinical applications for multiplanar- and three-dimensional-reconstructions by helical-CT for the diagnosis of acetabular fractures; Klinischer Einsatz multiplanarer und 3D-Rekonstruktionen der Spiral-CT in der Diagnostik der Azetabulumfrakturen

    Energy Technology Data Exchange (ETDEWEB)

    Stroszczynski, C. [Strahlenklinik und Poliklinik im Virchow-Klinikum, Medizinische Fakultaet der Humboldt-Universitaet, Berlin (Germany); Schedel, H. [Strahlenklinik und Poliklinik im Virchow-Klinikum, Medizinische Fakultaet der Humboldt-Universitaet, Berlin (Germany); Stoeckle, U. [Unfallchirurgische Klinik und Poliklinik im Virchow-Klinikum, Medizinische Fakultaet der Humboldt-Universitaet, Berlin (Germany); Wellmann, A. [Strahlenklinik und Poliklinik im Virchow-Klinikum, Medizinische Fakultaet der Humboldt-Universitaet, Berlin (Germany); Beier, J. [Deutsches Herzzentrum Berlin, Virchow-Klinikum, Abt. Innere Medizin und Kardiologie (Germany); Wicht, L. [Strahlenklinik und Poliklinik im Virchow-Klinikum, Medizinische Fakultaet der Humboldt-Universitaet, Berlin (Germany); Hoffmann, R. [Unfallchirurgische Klinik und Poliklinik im Virchow-Klinikum, Medizinische Fakultaet der Humboldt-Universitaet, Berlin (Germany); Felix, R. [Strahlenklinik und Poliklinik im Virchow-Klinikum, Medizinische Fakultaet der Humboldt-Universitaet, Berlin (Germany)

    1996-03-01

    This review describes recent visualizations of computed tomography for the diagnosis of acetabular fractures. The techniques of conventional and helical-CT for the imaging of the acetabulum are compared. Furthermore, the different methods of multiplaner and three-dimensional reconstructions e.g. shaded surface display, maximum intensity projection, and volume rendering are presented. Figures of multiplanar and three-dimensional imaging for fractures of the pelvis is discussed. (orig.) [Deutsch] Es wird eine Uebersicht moderner computertomographischer Darstellungsmethoden der Azetabulumfrakturen vorgestellt. Auf die einzelnen Charaktersitika der konventionellen und Spiral-CT-Technik wird eingegangen, weiterhin werden die multiplanaren und verschiedenen 3dimensionalen Rekonstruktionsverfahren Shaded-Surface-Display (SSD), Maximum-Intensitaetsprojektion (MIP) und Volume-Rendering (VR) beschrieben und jeweils anhand von Abbildungen erlaeutert. Darueber hinaus wird das diagnostische Potential der einzelnen Methoden diskutiert. (orig.)

  8. 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

  9. 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

  10. 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...

  11. 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.

  12. 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

  13. 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。

  14. 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

  15. 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

  16. Precision acetabular tumor resection and reconstruction using custom prosthesis with the help of Computer Assisted Navigation System%计算机导航辅助髋臼肿瘤精确切除与重建

    Institute of Scientific and Technical Information of China (English)

    张涌泉; 郭征; 付军; 王臻; 范宏斌; 栗向东; 裴延军; 吕心建; 袁超凡

    2013-01-01

    Objective To investigate an effective method to reconstruct acetabular defect using custom prosthesis after tumor En-bloc resection with the help of Computer Assisted Navigation System(CANS).Methods 3D model of image fusion was reconstructed using the preoperative CT and MRI data.The tumor invasion range,the safe resection boundaries and osteotomy planes were marked on the 3D model.A custom acetabular prosthesis was designed and manufactured using CAD/CAM techniques according to pelvic defects.With the help of CANS,the tumor was accurately resected and the custom prosthesis was fixed precisely according to the preoperative planning.We formulated the innovative treatment process.Between December 2010 and May 2012,3 patients with primary malignant acetabular tumor underwent the treatment process.They were males,aged from 30 to 55 years.There were 2 cases of chondrosarcoma and 1 case of primitive neuroectodermal tumor (PNET).The tumors involved zone Ⅱ +Ⅲ in all of cases.All 3 patients were followed up,and complications,MSTS score and prognosis were recorded.Results The tumors in all 3 cases were resected successfully,and the acetabular defects were reconstructed precisely with custom prosthesis.All the 3 patients were followed up for 12 to 21 months.At the final follow-up,3 patients survived without recurrence.No such complications as deep infection,dislocation,prosthesis loosening and screw broken occurred during the follow-up period.The MSTS score was 18-26.Conclusion The process is effective for the treatment of acetabular tumors.Acetabular tumor can be En-bloc resected safely and custom prosthesis can be fixed precisely with the help of CANS.According to the process,accurate tumor resection and precise reconstruction can be achieved.The rate of complications is low.The short-term result is fine,while the long-term result needs further observation.%目的 探索髋臼恶性肿瘤精确切除与重建的有效方法,评价其临床治疗效果.方法 利用图

  17. Dynamic Component Composition

    Directory of Open Access Journals (Sweden)

    Efim Grinkrug

    2014-07-01

    Full Text Available This paper presents an approach to dynamic component composition that facilitates creating new composed components using existing ones at runtime and without any code generation. The dynamic abilities are supported by extended type notion and implementation based on additional superstructure provided with its Java API and corresponding JavaBeans components. The new component composition is performed by building the composed prototype object that can be dynamically transformed into the new instantiable type (component. That approach demonstrates interrelations between prototype-based and class-based component-oriented programming. The component model proposed can be used when implementing user-defined types in declarative languages for event-driven applications programming.

  18. Experimental research of acetabular abduction angle and anteversion measurement by three-dimensional reconstruction of multi-slice spiral CT%多层螺旋CT三维重建测量髋臼外展角及前倾角的实验研究

    Institute of Scientific and Technical Information of China (English)

    范新成; 葛东; 刘峰; 魏开斌; 马振波; 张伟; 赵伟; 李军; 朱海涛; 初培罡

    2014-01-01

    Objective To investigate a new method of three-dimensional reconstruction of multi-slice spiral CT in measurement of acetabular abduction angle and acetabular anteversion. Methods The research objects were 60 acetabulars of 30 pelvic specimens, acetabular abduction angle and acetabular anteversion were measured respectively by radiological and actual measurements. The first one using digital X-ray photography and three-dimensional reconstruction of multi-slice spiral CT. The second one using a protractor and digital goniometer two methods. Results The acetabular abduction angle and anteversion were (48.61±2.31)° and (15.82±4.62)° respectively, there was no statistically significant difference of these two angles between actual measurement and radiological measurement(P>0.05). There were no significant differences for each angle between radiological and actual measurements(P>0.05). Conclusions The measurement of acetabular abduction angle and anteversion by MSCT three-dimensional reconstruction were accurate, which provide a new and standardized method of measurement of acetabular abduction angle and anteversion. The digital goniometer provide an accurate and convenient new method for specimens’ anatomical measurements.%目的:探讨应用多层螺旋CT(multi-slice spiral CT,MSCT)三维重建精确测量髋臼外展角及前倾角的新方法。方法选用30具成人完整骨盆标本共60个髋臼为研究对象,应用放射学方法及实际测量法分别对其外展角、前倾角进行测量,放射学方法采用数字化 X 线摄影(digital X-ray radiography,DR)及MSCT三维重建两种方法,实际测量采用量角器及数显角度仪两种方法。结果 MSCT重建法测得的髋臼外展角为48.61°±2.31°,前倾角为15.82°±4.62°,与实际测量结果比较,差异均无统计学意义(P>0.05);放射学方法与实际测得的髋臼外展角、前倾角分别比较,差异均无统计学意义(P>0.05

  19. Experimental research and its clinical significance of precise postural adjustment and mean measurement by multi-slice spiral CT reconstruction of acetabular abduction angle%测量髋臼外展角度的实验研究及其临床意义MSCT三维重建精确体位调整均值法

    Institute of Scientific and Technical Information of China (English)

    范新成; 马振波; 于春丽; 朱海涛; 赵伟; 彭国庆; 张伟; 魏开斌; 刘峰

    2016-01-01

    Objective:To investigate the application of multi-slice spiral CT reconstruction accurate measurement of ace-tabular abduction angle,and to provide a scientific basis for guidance of total hip replacement acetabular prosthesis individu-alized accurate placement and postoperative evaluation. Methods:The research objects were 60 acetabulars of 30 pelvic spec-imens,and with anterior plane of pelvis as a reference plane,acetabular abduction angles were measured respectively by digital goniometer and multi-slice CT reconstruction with precise postural adjustment. Results:The acetabular abduction an-gle means of 30 pelvic specimens by digital goniometer and multi-slice CT reconstruction with precise postural adjustment were(48. 73 ± 3. 19)°and(48. 65 ± 2. 47)° respectively,and they had no significant difference(P > 0. 05). These data showed that the measurement of acetabular abduction angle by multi-slice CT reconstruction with precise postural ad-justment was accurate,which had no significant difference from the actual measurement. Conclusion:Multi-slice CT recon-struction with precise postural adjustment,with the anterior plane of the pelvis as a reference plane,is a new method of a preoperative acetabular abduction angle measurement for total hip arthroplasty,which can reduce human error in operation and achieve standardized measurement and evaluation of hip acetabular abduction angle.%目的:探讨应用 MSCT 三维重建精确测量髋臼外展角度的新方法,为指导全髋关节置换髋臼假体个体化准确置入及术后评估提供科学依据。方法选取30具骨盆标本共60个髋臼为研究对象,以骨盆前平面为参照平面,分别应用数显角度仪及 MSCT 三维重建精确体位调整均值法对髋臼外展角度数值进行测量,对两种方法的测量结果进行比较。结果应用数显角度仪及 MSCT 三维重建精确体位调整均值法测量髋臼外展角度分别为(48.73±3.19)°和(48.65±2.47)°

  20. 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

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Multilevel component analysis

    NARCIS (Netherlands)

    Timmerman, M.E.

    2006-01-01

    A general framework for the exploratory component analysis of multilevel data (MLCA) is proposed. In this framework, a separate component model is specified for each group of objects at a certain level. The similarities between the groups of objects at a given level can be expressed by imposing cons

  7. 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

  8. 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.

  9. 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

  10. GCS component development cycle

    Science.gov (United States)

    Rodríguez, Jose A.; Macias, Rosa; Molgo, Jordi; Guerra, Dailos; Pi, Marti

    2012-09-01

    The GTC1 is an optical-infrared 10-meter segmented mirror telescope at the ORM observatory in Canary Islands (Spain). First light was at 13/07/2007 and since them it is in the operation phase. The GTC control system (GCS) is a distributed object & component oriented system based on RT-CORBA8 and it is responsible for the management and operation of the telescope, including its instrumentation. GCS has used the Rational Unified process (RUP9) in its development. RUP is an iterative software development process framework. After analysing (use cases) and designing (UML10) any of GCS subsystems, an initial component description of its interface is obtained and from that information a component specification is written. In order to improve the code productivity, GCS has adopted the code generation to transform this component specification into the skeleton of component classes based on a software framework, called Device Component Framework. Using the GCS development tools, based on javadoc and gcc, in only one step, the component is generated, compiled and deployed to be tested for the first time through our GUI inspector. The main advantages of this approach are the following: It reduces the learning curve of new developers and the development error rate, allows a systematic use of design patterns in the development and software reuse, speeds up the deliverables of the software product and massively increase the timescale, design consistency and design quality, and eliminates the future refactoring process required for the code.

  11. Robust Principal Component Analysis?

    CERN Document Server

    Candes, Emmanuel J; Ma, Yi; Wright, John

    2009-01-01

    This paper is about a curious phenomenon. Suppose we have a data matrix, which is the superposition of a low-rank component and a sparse component. Can we recover each component individually? We prove that under some suitable assumptions, it is possible to recover both the low-rank and the sparse components exactly by solving a very convenient convex program called Principal Component Pursuit; among all feasible decompositions, simply minimize a weighted combination of the nuclear norm and of the L1 norm. This suggests the possibility of a principled approach to robust principal component analysis since our methodology and results assert that one can recover the principal components of a data matrix even though a positive fraction of its entries are arbitrarily corrupted. This extends to the situation where a fraction of the entries are missing as well. We discuss an algorithm for solving this optimization problem, and present applications in the area of video surveillance, where our methodology allows for th...

  12. Custom-designed orthopedic implants evaluated using finite element analysis of patient-specific computed tomography data: femoral-component case study

    Directory of Open Access Journals (Sweden)

    Nayfeh Jamal F

    2007-09-01

    Full Text Available Abstract Background Conventional knee and hip implant systems have been in use for many years with good success. However, the custom design of implant components based on patient-specific anatomy has been attempted to overcome existing shortcomings of current designs. The longevity of cementless implant components is highly dependent on the initial fit between the bone surface and the implant. The bone-implant interface design has historically been limited by the surgical tools and cutting guides available; and the cost of fabricating custom-designed implant components has been prohibitive. Methods This paper describes an approach where the custom design is based on a Computed Tomography scan of the patient's joint. The proposed design will customize both the articulating surface and the bone-implant interface to address the most common problems found with conventional knee-implant components. Finite Element Analysis is used to evaluate and compare the proposed design of a custom femoral component with a conventional design. Results The proposed design shows a more even stress distribution on the bone-implant interface surface, which will reduce the uneven bone remodeling that can lead to premature loosening. Conclusion The proposed custom femoral component design has the following advantages compared with a conventional femoral component. (i Since the articulating surface closely mimics the shape of the distal femur, there is no need for resurfacing of the patella or gait change. (ii Owing to the resulting stress distribution, bone remodeling is even and the risk of premature loosening might be reduced. (iii Because the bone-implant interface can accommodate anatomical abnormalities at the distal femur, the need for surgical interventions and fitting of filler components is reduced. (iv Given that the bone-implant interface is customized, about 40% less bone must be removed. The primary disadvantages are the time and cost required for the

  13. Virtual operation planning in orthopedic surgery for acetabular fractures based on real CT data%基于真实CT数据骨科虚拟手术计划在髋臼骨折手术中的运用

    Institute of Scientific and Technical Information of China (English)

    汪光晔; 张春才; 许硕贵; 薜双桃; 林清高

    2011-01-01

    BACKGROUND: Virtual operation planning can help surgeons to improve the accuracy of orthopedic operations. OBJECTIVE:To test the feasibility and clinical value of preoperative virtual surgical planning in pelvis and acetabular fractures using Mimics software based on an interactive virtual reality-style environment.METHODS: Thirteen patients with pelvis and acetabular fractures were scanned with spiral CT preoperatively. The real data from CT in DICOM format were transformed into Mimics software. With segmentation process, each fracture segment became a separate object. Bone fragments could be moved and rotated in all three planes and reduction was performed Then we performed all the steps of the surgical procedure.RESULTS AND CONCLUSION: The median time needed to segment the osseous parts of an entire pelvis and to extract a surface model was 45 minutes (ranging 30 to 70 minutes), and the median time for fracture reduction was 28 minutes (ranging 16 to 45 minutes). The planned approach was followed in 12 of the 13 cases, the planned fixation was followed completely in 12 cases and partially in 1 cases. The screw count was identical to the planned operation in 10 cases, the screw length was Identical in 8 cases, and fixation plate count was Identical in 11 cases. Postoperative congruence of the acetabular joint surface as determined according to Matta in the follow-up CT was anatomic in 6 cases (46%) and satisfactory In 7 cases (54%). There was no case with inadvertent penetration of the hip joint Virtual operation planning in orthopedic surgery is helpful for enacting accurate operation program and providing data reference for actual operation, which brings significant value and new opportunities in clinical practice.%背景:骨科虚拟手术计划有助于提高外科医生的手术精确性.目的:探索计算机术前模拟手术技术在骨盆、髋臼骨折的治疗中的应用方法及临床价值.方法:对13例骨盆及髋臼骨折患者进行螺旋CT影

  14. 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...

  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. 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

  17. Component fragility research program

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, N.C.; Mochizuki, G.L.; Holman, G.S. (NCT Engineering, Inc., Lafayette, CA (USA); Lawrence Livermore National Lab., CA (USA))

    1989-11-01

    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 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. 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...

  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. 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.

  1. 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.

  2. 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...

  3. Residual Component Analysis

    CERN Document Server

    Kalaitzis, Alfredo A

    2011-01-01

    Probabilistic principal component analysis (PPCA) seeks a low dimensional representation of a data set in the presence of independent spherical Gaussian noise, Sigma = (sigma^2)*I. The maximum likelihood solution for the model is an eigenvalue problem on the sample covariance matrix. In this paper we consider the situation where the data variance is already partially explained by other factors, e.g. covariates of interest, or temporal correlations leaving some residual variance. We decompose the residual variance into its components through a generalized eigenvalue problem, which we call residual component analysis (RCA). We show that canonical covariates analysis (CCA) is a special case of our algorithm and explore a range of new algorithms that arise from the framework. We illustrate the ideas on a gene expression time series data set and the recovery of human pose from silhouette.

  4. Cognitive Component Analysis

    DEFF Research Database (Denmark)

    Feng, Ling

    2008-01-01

    This dissertation concerns the investigation of the consistency of statistical regularities in a signaling ecology and human cognition, while inferring appropriate actions for a speech-based perceptual task. It is based on unsupervised Independent Component Analysis providing a rich spectrum...... of 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 process of unsupervised grouping of generic data such that the ensuing group structure is well-aligned with that resulting from human cognitive activity. Its hypothesis runs ecologically: features which are essentially independent in a context defined ensemble, can be efficiently coded as sparse...

  5. Component Reengineering Workshops

    DEFF Research Database (Denmark)

    Hansen, Klaus Marius; Christensen, Henrik Bærbak

    2004-01-01

    In mature domains, a number of competing product lines may emerge, and from the point of view of customers of such product lines, reengineering and reuse of assets across product lines from different vendors becomes important. To address this issue we present a low-cost approach, component...... 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...

  6. 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....

  7. 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

  8. 经皮髋臼成形术穿刺部位的解剖学研究%Anatomic study on the puncture point of the percutaneous acetabular reconstruction

    Institute of Scientific and Technical Information of China (English)

    蒋昆利; 梁清福; 王俊江; 田征

    2016-01-01

    目的:从解剖学角度探讨经皮髋臼成形术治疗髋臼转移瘤患者手术入路的最佳穿刺点、深度。方法选用30具经防腐固定处理的成人去肌肉骨盆髋关节标本和2具完整成人尸体标本。以髋臼中点为 O 点,过髂前上棘和 O 点做1条直线,再做1条过 O 点且垂直于该直线的直线,2条直线分别与髋臼边缘交于 A、B 点,并把髋臼分为4个象限。∠AOB 的角平分线与髋臼边缘交于 C 点。设髋臼顶点为0时,测量大转子顶点所在水平面与 A、B、C 各点所在水平面的垂直距离及 A、B、C 3点在髋臼边缘外10 mm 相对应 A’、B’、C’3点处的髋臼后壁厚度。根据测量的数据得出最佳穿刺点和深度,对2具完整尸体标本行髋臼穿刺操作并灌注骨水泥验证。结果A’点位于大转子顶点上方31.6~38.4 mm,男性平均34.9 mm,女性平均34.2 mm;B’点位于与 A’点相同距离的10~11点钟位置;C’点位于转子顶点上方33.8~42.5 mm,男性平均距离36.7 mm,女性35.5 mm 的0点钟位置。A’、B’、C’对应的体表投影点即为穿刺部位。其穿刺深度分别为6.7~8.4、17.7~20.4、14.7~17.9 mm,平均深度约分别为7.5、18.5、16.5 mm。经验证髋臼成形术最佳进针点结果成立。结论A’、B’、C’3点的体表投影点均可为行髋臼成形术的穿刺点,3个穿刺点可以较短距离到达髋臼后上象限区的肿瘤。%Objective To discuss the optimal puncture point and depth of percutaneous acetabulum forming operation for treatment of acetabular tumor on the basis of anatomical angle.Methods 30 adult pelvis and hip specimens without muscle fixed with formol and 2 complete cadavers were anatomized and measured. Set the central of acetabulum as point O,from the point O,let a vertical line intersected line which went through the point of spina iliaca anterior superior and the point O

  9. Establishment of classified pelvic and acetabular fractures and their significance%骨盆髋臼骨折三维数字化分型系统的建立及其意义

    Institute of Scientific and Technical Information of China (English)

    王会祥; 汪方; 王秋根; 林艳萍; 陈豪; 陶星光

    2013-01-01

    目的 建立骨盆、髋臼骨折三维数字化分型系统,评价其对骨科临床及教学的指导意义.方法 将一名健康男性志愿者CT扫描所得数据转换成DICOM格式并导入Mimics10.01软件中进行处理,分别重建骨盆、髋臼模型,同时模拟出国际内固定研究学会(A0)分型中各型骨盆、髋臼骨折,对各骨折块予以不同颜色渲染,并将完成制作的骨折三维模型以标准三维图形(STL)文件格式保存.利用视觉化图像工具库(VTK)及跨平台C+ +图形用户界面应用程序开发框架(Qt)等软件开发工具,完成骨盆、髋臼骨折三维数字化分型软件开发.10名骨科医生及20名医学生分别将三维数字化骨盆、髋臼骨折AO分型图谱和传统的二维分型图谱与患者影像学资料进行对比,并给予初步评价.结果 骨盆、髋臼骨折三维数字化分型软件可实现对骨折三维模型的旋转及放缩等操作,从任意角度观察骨折模型.9名骨科医生及18名医学生评价提示,三维数字化骨折分型系统与传统的二维平面分型系统相比,利于对骨盆、髋臼骨折AO分型的理解和判断.结论 骨盆、髋臼骨折三维数字化分型系统具有逼真、直观、立体、动态等特点,对于骨科临床及医学教学具有积极意义.%Objective To establish three-dimensional (3D) digital classification models of pelvic and acetabular fractures and evaluate its significance in orthopaedic clinical and teaching work. Methods Pelvic of a healthy male volunteer was scanned with CT, and the resulting data in DICOM format was imported to Mimics10. 01 software to reconstruct the model of the pelvis and acetabulum respectively. Based on the standards of AO/ASIF classification of pelvic and acetabular fractures, various types of fractures were simulated. The fracture fragments were displayed with different colors. The completed fracture models were saved in STL format. By use of VTK and Qt softwares, the software

  10. 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:

  11. Acetabular fractures--Risk factors for a negative outcome of the surgical management%髋臼骨折--手术治疗效果欠佳的不利因素

    Institute of Scientific and Technical Information of China (English)

    Beate P. Hanson; David L. Helfet; Suthorn Bavonratanavech; Ian Harris; 陈国奋; 顾立强

    2004-01-01

    现有文献中没有确定性的治疗髋臼移位骨折的最佳方法.一般情况下倾向于开放复位内固定.但是,由于缺少不同特定内固定物间的比较,因此难以做出推荐.报道一致认为,导致结果差和一般的潜在不利因素包括老龄、术后复位不良、严重的骨折、股骨头损伤,以及延迟处理.%The optimal method of managing displaced acetabular fractures is not established in the literature.It may be that open reduction and internal fixation in general is universally preferred;however,specific types of hardware have not been compared and therefore recommendations cannot be made. Potential risk factors consistently reported to be associated with poor to fair outcomes include older age, poor post operative reduction, more severe fracture characteristics, femoral head injury, and a delay in treatment.

  12. 髋臼骨折病态肥胖对内固定术后并发症的影响%Acetabular fractures Impact of morbid obesity on complications afier fixation

    Institute of Scientific and Technical Information of China (English)

    Andrea C Skelly

    2011-01-01

    SummaryThree retrospective cohort studies of patients with acetabular fractures examined the impact of morbid obesity on patient complications after operative fracture fixation.The morbidly obese patient appears to have an elevated risk of more perioperative blood loss and of wound infection. While a higher rate of nerve palsy and pulmonary embolism was reported among morbidly obese patients compared with those in other weight categories in all studies, statistical significance was not achieved.One study reported increased risk of deep vein thrombosis (DVT) for obese patients compared with normal-weight patients.3项回顾性队列研究试图阐明髋臼骨折内固定术后,患者合并病态肥胖对术后并发症的影响。研究显示病态肥胖的患者术中失血量和伤口感染率更高。虽然与其他体质量的患者相比,病态肥胖的患者出现神经麻痹和肺栓塞的几率更高,但差异无统计学意义。1项研究报道,与正常体质量患者相比,肥胖患者深静脉血栓形成(DVT)的发生率更高。

  13. 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.

  14. Grey component analysis

    NARCIS (Netherlands)

    Westerhuis, J.A.; Derks, E.P.P.A.; Hoefsloot, H.C.J.; Smilde, A.K.

    2007-01-01

    The interpretation of principal component analysis (PCA) models of complex biological or chemical data can be cumbersome because in PCA the decomposition is performed without any knowledge of the system at hand. Prior information of the system is not used to improve the interpretation. In this paper

  15. 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....

  16. 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 ...

  17. 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...

  18. 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.

  19. Multimode geodesic branching components

    Science.gov (United States)

    Schulz, D.; Voges, E.

    1983-01-01

    Geodesic branching components are investigated for multimode guided wave optics. Geodesic structures with particular properties, e.g. focussing star couplers, are derived by a synthesis technique based on a theorem of Toraldo di Francia. Experimentally, the geodesic surfaces are printed on acrylic glass and are spin-coated with organic film waveguides.

  20. Towards Software Component Procurement Automation

    NARCIS (Netherlands)

    Gross, H-G.; Lormans, M.; Zhou, J.

    2007-01-01

    One of the first steps of component procurement is the identification of required component features in large repositories of existing components. On the highest level of abstraction, component requirements as well as component descriptions are usually written in natural language. Therefore, we can

  1. Food Components and Supplements

    DEFF Research Database (Denmark)

    Parlesak, Alexandr

    2012-01-01

    .g., secondary plant metabolites such as flavonoids), or as contaminants that enter the food chain at different stages or during the food production process. For these components, a wide spectrum of biological effects was observed that ranges from health-threatening impacts (e.g., polycyclic aromatic amines...... the growth of these bacteria (prebiotics) are added to food to achieve health effects exceeding its pure nutritional function. Several of these effects are mediated by enzyme systems involved in xenobiotic and drug metabolism, and in some cases this might lead to undesired interactions with medication...... cases, nutrients, food contaminants, and secondary plant metabolites can themselves become substrates for xenobiotic-metabolizing enzymes, resulting in health-promoting or health-threatening products. This chapter focuses on how important components of our daily nutrition and supplements can interfere...

  2. 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.......g., secondary plant metabolites such as flavonoids), or as contaminants that enter the food chain at different stages or during the food production process. For these components, a wide spectrum of biological effects was observed that ranges from health-threatening impacts (e.g., polycyclic aromatic amines......, 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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

  7. 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...

  8. 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.

  9. Stable Principal Component Pursuit

    CERN Document Server

    Zhou, Zihan; Wright, John; Candes, Emmanuel; Ma, Yi

    2010-01-01

    In this paper, we study the problem of recovering a low-rank matrix (the principal components) from a high-dimensional data matrix despite both small entry-wise noise and gross sparse errors. Recently, it has been shown that a convex program, named Principal Component Pursuit (PCP), can recover the low-rank matrix when the data matrix is corrupted by gross sparse errors. We further prove that the solution to a related convex program (a relaxed PCP) gives an estimate of the low-rank matrix that is simultaneously stable to small entrywise noise and robust to gross sparse errors. More precisely, our result shows that the proposed convex program recovers the low-rank matrix even though a positive fraction of its entries are arbitrarily corrupted, with an error bound proportional to the noise level. We present simulation results to support our result and demonstrate that the new convex program accurately recovers the principal components (the low-rank matrix) under quite broad conditions. To our knowledge, this is...

  10. 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

  11. Structural modifications induced by compressive plastic deformation in single-step and sequentially irradiated UHMWPE for hip joint components.

    Science.gov (United States)

    Puppulin, Leonardo; Sugano, Nobuhiko; Zhu, Wenliang; Pezzotti, Giuseppe

    2014-03-01

    Structural modifications were studied at the molecular scale in two highly crosslinked UHMWPE materials for hip-joint acetabular components, as induced upon application of (uniaxial) compressive strain to the as-manufactured microstructures. The two materials, quite different in their starting resins and belonging to different manufacturing generations, were a single-step irradiated and a sequentially irradiated polyethylene. The latter material represents the most recently launched gamma-ray-irradiated polyethylene material in the global hip implant market. Confocal/polarized Raman spectroscopy was systematically applied to characterize the initial microstructures and the microstructural response of the materials to plastic deformation. Crystallinity fractions and preferential orientation of molecular chains have been followed up during in vitro deformation tests on unused cups and correlated to plastic strain magnitude and to the recovery capacity of the material. Moreover, analyses of the in vivo deformation behavior of two short-term retrieved hip cups are also presented. Trends of preferential orientation of molecular chains as a function of residual strain were similar for both materials, but distinctly different in their extents. The sequentially irradiated material was more resistant to plastic deformation and, for the same magnitude of residual plastic strain, possessed a higher capacity of recovery as compared to the single-step irradiated one.

  12. 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

  13. Similar component analysis

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong; WANG Xin; LI Junwei; CAO Xianguang

    2006-01-01

    A new unsupervised feature extraction method called similar component analysis (SCA) is proposed in this paper. SCA method has a self-aggregation property that the data objects will move towards each other to form clusters through SCA theoretically,which can reveal the inherent pattern of similarity hidden in the dataset. The inputs of SCA are just the pairwise similarities of the dataset,which makes it easier for time series analysis due to the variable length of the time series. Our experimental results on many problems have verified the effectiveness of SCA on some engineering application.

  14. 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.

  15. 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.

  16. 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.

  17. One-component nanomedicine.

    Science.gov (United States)

    Su, Hao; Koo, Jin Mo; Cui, Honggang

    2015-12-10

    One-component nanomedicine (OCN) represents an emerging class of therapeutic nanostructures that contain only one type of chemical substance. This one-component feature allows for fine-tuning and optimization of the drug loading and physicochemical properties of nanomedicine in a precise manner through molecular engineering of the underlying building blocks. Using a precipitation procedure or effective molecular assembly strategies, molecularly crafted therapeutic agents (e.g. polymer-drug conjugates, small molecule prodrugs, or drug amphiphiles) could involuntarily aggregate, or self-assemble into nanoscale objects of well-defined sizes and shapes. Unlike traditional carrier-based nanomedicines that are inherently multicomponent systems, an OCN does not require the use of additional carriers and could itself possess desired physicochemical features for preferential accumulation at target sites. We review here recent progress in the molecular design, conjugation methods, and fabrication strategies of OCN, and analyze the opportunities that this emerging platform could open for the new and improved treatment of devastating diseases such as cancer.

  18. 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.

  19. 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

  20. The application of 3D printing technique in the research of acetabular fractures%3D打印应用于髋臼骨折数字化设计的实验研究

    Institute of Scientific and Technical Information of China (English)

    吴章林; 林海滨; 张国栋; 陆俭军; 陈宣煌; 黄华军; 黄文华

    2014-01-01

    Objective To evaluate the digital design of acetabular fractures and the feasibility of the implementation, then using the 3D printing technique to verify the results. Methods Fifty-two patients with acetabular fractures were enrolled in this study. Data of lamellar CT scanning were imported into Mimics14.0 software for 3D anatomical modeling and virtual fracture reduction. Then the default embedded steel plate location was optimized , the screw path evaluated,and the screw length measured. 3D printing technique was used to print the bone. Plates were bended based on the printing bones. Internal fixation implants were simulated based on all the printed bones and bended plates. Finally, the real operation was compared with virtual preoperative design in terms of the fixation position of plates, the direction and the length of screws. Results In the study, 61 plates and 424 screws were planted. The position of plates and the direction of screws were in high accordance with the digital design. The length of screws are compared with Paired-samples t Test and P=0.325. Conclusion Firstly, the combination of the digital design and 3D printing technique have a good application in the bending of the plates and surgery simulation before operation. The real operation is quite consistent with the simulated results. Secondly, plate bending before the real operation has a certain value in the guidance of fracture reduction.%目的:探讨髋臼骨折数字化设计及实施的可行性方案并以3D打印技术进行验证。方法采集52例临床髋臼骨折薄层CT扫描数据,在Mimics14.0中进行三维建模和虚拟骨折复位并在复位模型上优化预设植入钢板位置和虚拟钉道模拟、测量钉道长度,三维切割预设植入钢板部位骨块并3D打印,据此进行钢板折弯。将所有骨折块进行3D打印为实体模型结合折弯钢板进行内固定植入模拟。将钢板现实位置、螺钉方向和长度同数字化

  1. Periacetabular rotational osteotomy through the medial wall of ilium for the treatment of acetabu-lar dysplasia%经髂骨内侧壁髋臼周围旋转截骨治疗髋臼发育不良

    Institute of Scientific and Technical Information of China (English)

    薛源; 冯香; 高化富; 张印峰

    2014-01-01

    Objective To investigate the effect of periacetabular rotational osteotomy through the medial wall of ilium on acetabular dysplasia. Methods Thirty-six patients with acetabular dysplasia were operated with periacetabular rotational osteotomy through medial wall of ilium. Firstly,the dissec-tion was performed in the subperiosteal plane of the medial ilium via the ilioinguinal incision to expose the medial wall of the bottom of acetabulum. Secondly,without dissecting the internal iliac vasculoneural sheaths,osteotome was used to complete the osteotomy around the acetabulum within 1. 5 cm. The supe-rior portion was greater sciatic notch and the inferior portion was pecten pubis and body of ischium. In or-der to isolate the acetabulum,the two layer cortical bone was cut through and without damaging the later-al periosteum. Thirdly,with the help of biofix rods,the acetabulum was rotated anterolaterally and inferi-orly to correct the Sharp angle to 35° and to restore the coverage rate of femoral head to 75% . Two stein-mann pins were used to put pressure on the medial wall of the bottom of acetabulum through anterior su-perior spine. Postoperatively,none of the operated patients was immobilized. Results Thirty-one of the total 36 patients had 7 to 82 months(average 22 months)of follow up. According to Mckay criteria,the effect was excellent in 21 cases and good in 8 cases. Conclusions Periacetabular rotational osteotomy through the medial wall of ilium for the treatment of acetabular dysplasia is an effective,simple method. It has the advantages of little influence on the stability of pelvis,reliable fixation without external fixa-tion,and can avoide the risk of complications. This method can not only alleviate the patients’pain in the injured hip,but also avoid or delay the development of osteoarthritis.%目的:探讨经髂骨内侧壁髋臼周围旋转截骨术治疗髋臼发育不良的疗效。方法应用经髂骨内侧壁髋臼周围旋转截骨术

  2. 髋臼骨折术后残留移位与髋关节功能的相关性分析%CORRELATION ANALYSIS BETWEEN RESIDUAL DISPLACEMENT AND HIP FUNCTION AFTER RECONSTRUCTION OF ACETABULAR FRACTURES

    Institute of Scientific and Technical Information of China (English)

    马坤龙; 方跃; 栾富钧; 屠重棋; 杨天府

    2012-01-01

    目的 通过术后CT评价髋臼骨折复位质量,探讨累及负重区和非负重区的残留移位(台阶移位和间隙移位)与术后髋关节功能的相关性. 方法 回顾分析2004年6月-2009年6月48例髋臼骨折患者术后CT检查和临床随访结果.患者均行切开复位内固定.术后均获随访,随访时间24~72个月,平均36个月;骨折均愈合.根据关节面残留移位是否累及负重顶,将患者分为负重区组(30例)和非负重区组(18例).髋关节功能按Merle d'Aubigné-Postel标准评定;术后关节面复位质量采用CT评价,于CT片上测量残留移位的两个指标(台阶移位和间隙移位)最大值.所得数据均采用Spearman秩相关检验分析. 结果 负重区组残留移位值与髋关节功能成强负相关性(rs=-0.722,P=0.001);非负重区组残留移位值与髋关节功能无相关性(rs=0.481,P=0.059).临床随访结果与相关性分析一致.负重区组台阶移位值与髋关节功能成极强负相关(rs=-0.825,P=0.002),而间隙移位值与髋关节功能无相关性(rs=0.577,P=0.134). 结论 髋臼骨折患者术后髋关节功能不仅与关节面残留移位大小相关,还与残留移位部位相关.与非负重区相比,累及负重区的残留移位是影响术后髋关节功能的关键因素;在负重区台阶移位值越大,髋关节功能越差.%Objective To investigate the relationships between residual displacement of weight-bearing and non weight-bearing zones (gap displacement and step displacement) and hip function by analyzing the CT images after reconstruction of acetabular fractures. Methods The CT measures and clinical outcome were retrospectively analyzed from 48 patients with displaced acetabular fracture between June 2004 and June 2009. All patients were treated by open reduction and internal fixation, and were followed up 24 to 72 months (mean, 36 months); all fractures healed after operation. The residual displacement involved the weight-bearing zone in

  3. 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

  4. 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.

  5. 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......Low-power base stations such as e.g. Femto-cells are one of the candidates for high data rate provisioning in local areas, such as residences, apartment complexes, business offices and outdoor hotspot scenarios. Unfortunately, the benefits are not without new challenges in terms of interference...... 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...

  6. 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.

  7. 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.

  8. Sprayed skin turbine component

    Science.gov (United States)

    Allen, David B

    2013-06-04

    Fabricating a turbine component (50) by casting a core structure (30), forming an array of pits (24) in an outer surface (32) of the core structure, depositing a transient liquid phase (TLP) material (40) on the outer surface of the core structure, the TLP containing a melting-point depressant, depositing a skin (42) on the outer surface of the core structure over the TLP material, and heating the assembly, thus forming both a diffusion bond and a mechanical interlock between the skin and the core structure. The heating diffuses the melting-point depressant away from the interface. Subsurface cooling channels (35) may be formed by forming grooves (34) in the outer surface of the core structure, filling the grooves with a fugitive filler (36), depositing and bonding the skin (42), then removing the fugitive material.

  9. 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

  10. Sensitivity Analysis of Component Reliability

    Institute of Scientific and Technical Information of China (English)

    ZhenhuaGe

    2004-01-01

    In a system, Every component has its unique position within system and its unique failure characteristics. When a component's reliability is changed, its effect on system reliability is not equal. Component reliability sensitivity is a measure of effect on system reliability while a component's reliability is changed. In this paper, the definition and relative matrix of component reliability sensitivity is proposed, and some of their characteristics are analyzed. All these will help us to analyse or improve the system reliability.

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. C形臂X线透视导航下微创经皮拉力螺钉治疗髋臼前柱骨折%Treatment of anterior acetabular column fracture with minimally invasive percutaneous lag screws by C-arm X-ray fluoroscopy-based navigation

    Institute of Scientific and Technical Information of China (English)

    司庆华; 唐佩福; 丁珮; 胡磊; 樊喻波; 张立海; 彭晔; 袁新成; 董天祥; 娄昕

    2013-01-01

      目的探讨C型臂X线机透视导航下使用微创经皮拉力螺钉内固定治疗髋臼前柱骨折的方法及疗效.方法对2009年3月-2011年9月,在我院创伤骨科住院的8例无移位或轻度移位的髋臼前柱骨折患者,应用C形臂X线透视导航,用微创经皮拉力螺钉治疗髋臼前柱骨折.按Nakatani分型:Ⅰ型4例,Ⅱ型3例,Ⅲ型1例.受伤致手术时间为2~7 d.结果8例患者,男5例,女3例,年龄19~69岁,共置入10枚髋臼前柱经皮螺钉,其中2例为双侧髋臼前柱骨折,其余6例为单侧髋臼前柱骨折,各置入1枚螺钉.术后8例全部获得随访,随访时间10~26个月.8例全部骨性愈合,1例遗留轻度移位,无血管神经损伤等并发症.结论 C型臂X线机透视导航下使用微创经皮拉力螺钉内固定治疗髋臼前柱骨折可提高螺钉的精确度,有利于功能康复.%Objective To study the treatment of anterior acetabular column fractures with minimally invasive percutaneous lag screws by C-arm X-ray fluoroscopy-based navigation. Methods Eight patients with no or mild shift of anterior acetabular column fractures were treated with minimally invasive percutaneous lag screw by C-arm X-ray fluoroscopy- based navigation in our department from March 2009 to September 2011. The fractures were classified as typeⅠin 4 patients, typeⅡin 3 patients, and typeⅢin 1 patient according to Nakatani classification. The time from fracture to operation was 2~7 days. Results Of the 8 patients with 10 screws inserted, 5 were males and 3 were females aged 19~69 years, 2 were diagnosed with bilateral anterior acetabular column fracture and 6 with unilateral anterior acetabular column fracture with 1 screw inserted, respectively. The patients were followed up for 10~26 months, during which their fractures were healed with no complications such as vascular and nerve injury except for mild shift in 1 patient. Conclusion Internal fixation of anterior acetabular column fractures with

  16. 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

  17. 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...

  18. 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...... by small examples, using UML as concrete syntax for various aspects, and is illustrated by one larger case study based on an industrial prototype of a complex component based system....

  19. 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.

  20. 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.

  1. Multilevel Contracts for Trusted Components

    CERN Document Server

    Messabihi, Mohamed; Attiogbé, Christian; 10.4204/EPTCS.37.6

    2010-01-01

    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.

  2. 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.

  3. 髋臼前倾角术前测量在全髋关节置换术中的临床意义%The clinical significance of preoperative measurement of acetabular anteversion in total hip replacement

    Institute of Scientific and Technical Information of China (English)

    蒲超; 张珊珊; 李伟; 吴青霞; 候小倩

    2014-01-01

    Objective Discussion the clinical significance of preoperative measurement of acetabular antever-sion in total hip replacement .Methods 121 patients were randomly assigned into normal group and preoperative measurement group .Made the statistical analysis of postoperative differ between anteversion of artificial acetabulum with preoperative measuring value within 1° and 5° ,and contrast the postoperative anteversion of artificial acetabulum in two groups .Results Postoperative error within 1° and 5° was 3 .13% ,29 .69% in preoperative measurement group respectively .There was no statistically significans in the difference of postoperative anteversion of artificial acetabu-lum between two groups .Conclusion acetabulum The preoperative measurement can improve the accuracy in playing artificial acetabulum ,but the accuracy of lay need to improve .%目的:探讨髋臼前倾角术前测量在全髋关节置换术中的临床意义。方法将121例需行全髋关节置换术的患者随机分入常规组和术前测量组。常规组按照前倾15°安放人工髋臼,术前测量组按照术前测量角度安放人工髋臼,并统计分析术前测量组术后人工髋臼前倾角度与术前测量值相差1°和5°的比例以及两组患者术后人工髋臼前倾角度差异。结果术前测量组人工髋臼前倾角度术后误差小于1°和5°的比例分别为3.13%和29.69%,常规组与术前测量组术后人工髋臼前倾角度比较,差异有统计学意义( P<0.05)。结论髋臼前倾角术前测量可提高人工髋臼安放的精确度,但安放的准确性还需进一步提高。

  4. 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.

  5. 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.

  6. Total Hip Arthroplasty for The Treatment of End-stage Acetabular Dysplasia%全髋关节置换术治疗晚期髋臼发育不良

    Institute of Scientific and Technical Information of China (English)

    李宇俊; 文立成; 曹永平; 杨昕

    2012-01-01

    Objective To explore the installing methods of hip prothesis in a total hip arthroplasty for patients of osteoarthritis secondary to end-stage acetabular dysplasia. Methods Between January 2002 and January 2008.a total of 60 hips in 52 patients with advanced osteoarthritis secondary to acetabular dysplasia underwent the total hip arthroplasty and were followed up. Among the patients,6 were male and 46 were female,with their ages ranging from 46 to 72 years and a average age of 62 years. The bilateral arthroplasty was performed in 8 patients and the unilateral arthroplasty in 44 patients. The main symptoms were pain and claudication. According to the developmental degree of acetabulums,three methods were adopted to perform the total hip arthroplasty,which were deepen acetabulum,inward deepening acetabulum and bone transplantation on external upper lip of acetabulum. The Harris scores were applied to evaluate function of the hip during follow-up. X-ray films for both joints were taken in order to learn the coalescence of acetablum with its bone bed after 3,6,9,12 months and every 1 years after operation. The follow-up time ranged from 2 years to 8 years,with an average of 4 years and 6 months. Results At the end of follow-up,the acetabulum prostheses contacted well with their beds of 45 years and the recovery of joint function was satisfactory and no sign of aseptic loosening among the cases of deepen acetabulum and inward deepened acetabulum. However,in 5 of 6 acetabulums which implanted bone on their external upper lip,there was a radiolucency between the implanted bone and the acetabulum prothesis after 2 years of the operation. No sign of aseptic loosening was found. Conclusion While performing total hip arthroplasty,various methods should be adopted according to the bed of acetabulum for the joints of osteoarthrosis due to acetabulum dysplasis. For the patient of enough bone at the bottom of acetabulum bed the acetabulum should be installed by the operation

  7. 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

  8. 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

  9. 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,...

  10. 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...

  11. 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...

  12. 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 certain...... point on in a development we would rather develop components separately. The other -behaviourally identical- components should not concern us when we are focusing on one of them. We have to ask the following question: How can we systematically extract "real" components from such a model...

  13. 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.

  14. 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

  15. 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.

  16. 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 .

  17. 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.

  18. 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

  19. 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

  20. 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 ...

  1. 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

  2. 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

  3. 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....

  4. 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.

  5. 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.

  6. 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.

  7. Component Fragility Research Program: Phase 1 component prioritization

    Energy Technology Data Exchange (ETDEWEB)

    Holman, G.S.; Chou, C.K.

    1987-06-01

    Current probabilistic risk assessment (PRA) methods for nuclear power plants utilize seismic ''fragilities'' - probabilities of failure conditioned on the severity of seismic input motion - that are based largely on limited test data and on engineering judgment. Under the NRC Component Fragility Research Program (CFRP), the Lawrence Livermore National Laboratory (LLNL) has developed and demonstrated procedures for using test data to derive probabilistic fragility descriptions for mechanical and electrical components. As part of its CFRP activities, LLNL systematically identified and categorized components influencing plant safety in order to identify ''candidate'' components for future NRC testing. Plant systems relevant to safety were first identified; within each system components were then ranked according to their importance to overall system function and their anticipated seismic capacity. Highest priority for future testing was assigned to those ''very important'' components having ''low'' seismic capacity. This report describes the LLNL prioritization effort, which also included application of ''high-level'' qualification data as an alternate means of developing probabilistic fragility descriptions for PRA applications.

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. 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,...

  13. Multiview Bayesian Correlated Component Analysis

    DEFF Research Database (Denmark)

    Kamronn, Simon Due; Poulsen, Andreas Trier; Hansen, Lars Kai

    2015-01-01

    Correlated component analysis as proposed by Dmochowski, Sajda, Dias, and Parra (2012) is a tool for investigating brain process similarity in the responses to multiple views of a given stimulus. Correlated components are identified under the assumption that the involved spatial networks...... are identical. Here we propose a hierarchical probabilistic model that can infer the level of universality in such multiview data, from completely unrelated representations, corresponding to canonical correlation analysis, to identical representations as in correlated component analysis. This new model, which...... we denote Bayesian correlated component analysis, evaluates favorably against three relevant algorithms in simulated data. A well-established benchmark EEG data set is used to further validate the new model and infer the variability of spatial representations across multiple subjects....

  14. 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

  15. Passive Microwave Components and Antennas

    DEFF Research Database (Denmark)

    State-of-the-art microwave systems always require higher performance and lower cost microwave components. Constantly growing demands and performance requirements of industrial and scientific applications often make employing traditionally designed components impractical. For that reason, the design...... and development process remains a great challenge today. This problem motivated intensive research efforts in microwave design and technology, which is responsible for a great number of recently appeared alternative approaches to analysis and design of microwave components and antennas. This book highlights...... techniques. Modelling and computations in electromagnetics is a quite fast-growing research area. The recent interest in this field is caused by the increased demand for designing complex microwave components, modeling electromagnetic materials, and rapid increase in computational power for calculation...

  16. 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....

  17. 人工全髋关节置换骨水泥和无骨水泥假体股骨近端广泛骨溶解的定量分析%Quantitative analysis of widespread osteolysis in the proximal end of cemented and cementless prostheses in total hip arthroplasty

    Institute of Scientific and Technical Information of China (English)

    张勇; 杨彤涛; 周勇; 马保安

    2006-01-01

    of osteolysis in proximal femur after total joint replacements (TJR) through the changing rules of bone density in proximal end of femur.DESIGN: Observation on patients before and after self-comparison.SETTING: Department of Orthopedics, Tangdu Hospital of Fourth Military Medical University of Chinese PLA.PARTICIPANTS: Twenty-eight hips in 26 patients received total hip replacements in the Department of Orthopedics, Tangdu Hospital of Fourth Military University from March 1994 to March 2004, including 16 hips in 14 male patients and 12 hips in 12 female patients, were selected. Types of prostheses: 17 hips in 16 patients with ameliorated Moore cemented prostheses were taken as cemented prosthesis group with a mean age of 57 years; 11 hips in 10 patients with microbores on the surface of implant were taken as cementless prosthesis group with a mean age of 55 years.Patients were diagnosed as traumatic arthritis before operation with the mean Harris score of 49 (20-77) points on hip. Age, gender and diagnosis after operation in patients of two groups were matched.METHODS: The gray degrees of X-ray in patients of two groups were measured with computer image analyzing, relative values were obtained,I.e. The average gray degrees of 1.0-2.0 cm2 area in femoral trochanter and iliac bone were measured with the same X-ray; Differences between them represented the relative value of bone density in greater trochanter of femur. Changing rules of bone density were quantitatively analyzed.MAIN OUTCOME MEASURES: Relative values of bone density in greater trochanter of femur of patients in two groups one week before and after operation, during the follow-up time were measured respectively.RESULTS: A total of 26 patients (28 hips) with the follow-up time of 9-126months were all involved in the analysis of results. Relative values of bone density were increased to different degree one week after operation. And rate of osteolysis was 100% with a mean value of 57.4 (9-118) in greater

  18. 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.

  19. The cup safe-zone and optimum combination of the acetabular and femoral anteversions in total hip arthroplasty%全髋关节置换术中髋臼假体位相的安全范围及杯颈前倾角的优化组合

    Institute of Scientific and Technical Information of China (English)

    李永奖; 蔡春元; 张力成; 杨国敬; 林瑞新; 余斌峰; 吴立军

    2012-01-01

    Objective To determine the cup safe-zone and the optimum combination of cup and neck anteversions in total hip arthroplasty(THA). Methods A three-dimensional generic parametric and kinematic simulation module of THA was developed.Ordinary and strict criteria were defined regarding hip ROM as follows:normal criteria:flexion ≥ 110°,intorsion ≥ 30° at 90° flexion,backward extension ≥ 30°and extorsion ≥40° at the neutral position without prosthetic impingement; strict criteria:flexion ≥ 120°,intorsion≥45°at 90° flexion,backward extension ≥30° and extoraion ≥40° at the neutral position without prosthetic impingement.The changes in die head-neck ratio (GR),die femoral neck anteversion (F.A),the operative inclination (OI) and anteversion(OA) of the cup component ranged respectively from 2.00 to 2.92,0 to 30°,10° to 60° and 0 to 70°.For the 2 collodiaphyseal angles(CCD) of 130° and 135°,the corresponding OA related to the OI at every 5° was calculated. Results The size of cup safe-zone by the strict criteria is smaller than that by the normal criteria,and the sizes are both increased when a larger GR is chosen.When the CCD-angle is 130°,the optimum relationships between acetabular OA and FA by the normal and strict criteria can be estimated with the formula: Y1 =-0.840X1 + 38.41 and Y2 =-1.007X2 +47.46 respectively. The minimum allowable operative inclination (O1min) of the acetabulum should be more than 168.13 GR1-2.504 and 213.79 GR2-2.272 respectively.When the CCD changes from 135° to 130°,the cup safe-zone moves to an arca of a smaller OA and shrinks slightly in area. Conclusions Although the more strict the criteria regarding hip ROM,the smaller the cup safe-zone,the reduced safe-zone can be retrieved by increasing the GR.The OImin is largely reduced with an increasing GR The OA is negatively associated with the FA.Increase in neck anteversion and decrease in CCD can move the cup safe-zone towards an area of a smaller OA.%目的

  20. 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.

  1. Additive manufacturing of optical components

    Science.gov (United States)

    Heinrich, Andreas; Rank, Manuel; Maillard, Philippe; Suckow, Anne; Bauckhage, Yannick; Rößler, Patrick; Lang, Johannes; Shariff, Fatin; Pekrul, Sven

    2016-08-01

    The development of additive manufacturing methods has enlarged rapidly in recent years. Thereby, the work mainly focuses on the realization of mechanical components, but the additive manufacturing technology offers a high potential in the field of optics as well. Owing to new design possibilities, completely new solutions are possible. This article briefly reviews and compares the most important additive manufacturing methods for polymer optics. Additionally, it points out the characteristics of additive manufactured polymer optics. Thereby, surface quality is of crucial importance. In order to improve it, appropriate post-processing steps are necessary (e.g. robot polishing or coating), which will be discussed. An essential part of this paper deals with various additive manufactured optical components and their use, especially in optical systems for shape metrology (e.g. borehole sensor, tilt sensor, freeform surface sensor, fisheye lens). The examples should demonstrate the potentials and limitations of optical components produced by additive manufacturing.

  2. Two component systems: physiological effect of a third component.

    Directory of Open Access Journals (Sweden)

    Baldiri Salvado

    Full Text Available Signal transduction systems mediate the response and adaptation of organisms to environmental changes. In prokaryotes, this signal transduction is often done through Two Component Systems (TCS. These TCS are phosphotransfer protein cascades, and in their prototypical form they are composed by a kinase that senses the environmental signals (SK and by a response regulator (RR that regulates the cellular response. This basic motif can be modified by the addition of a third protein that interacts either with the SK or the RR in a way that could change the dynamic response of the TCS module. In this work we aim at understanding the effect of such an additional protein (which we call "third component" on the functional properties of a prototypical TCS. To do so we build mathematical models of TCS with alternative designs for their interaction with that third component. These mathematical models are analyzed in order to identify the differences in dynamic behavior inherent to each design, with respect to functionally relevant properties such as sensitivity to changes in either the parameter values or the molecular concentrations, temporal responsiveness, possibility of multiple steady states, or stochastic fluctuations in the system. The differences are then correlated to the physiological requirements that impinge on the functioning of the TCS. This analysis sheds light on both, the dynamic behavior of synthetically designed TCS, and the conditions under which natural selection might favor each of the designs. We find that a third component that modulates SK activity increases the parameter space where a bistable response of the TCS module to signals is possible, if SK is monofunctional, but decreases it when the SK is bifunctional. The presence of a third component that modulates RR activity decreases the parameter space where a bistable response of the TCS module to signals is possible.

  3. 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.

  4. 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.

  5. 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

  6. 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...

  7. Bioactivity of Minor Milk Components

    DEFF Research Database (Denmark)

    Nguyen, Duc Ninh

    of 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...

  8. Carcinogenicity of hair dye components.

    Science.gov (United States)

    Van Duuren, B L

    1980-03-01

    The available animal carcinogenicity data on hair dye components was reviewed. From this review it became clear that certain hair dye components, some of which are still in hair dye formulations now on the market, are animal carcinogens. The compounds of concern that are still in use are: 3-amino-4-methoxyaniline, 2-nitro-4-aminoaniline and 3-nitro-4-hydroxyaniline. Certain azo dyes formerly used, and related compounds still in use, contain the benzidine moiety. Two of these compounds, Direct Blue 6 and Direct Black 38, have been shown to be metabolized in animals to the human carcinogen benzidine. Furthermore, skin absorption studies carried out with radiolabeled hair dye components applied to animal or human skin have conclusively shown that these compounds are systemically absorbed and excreted. Known cocarcinogens such as catechol and pyrogallol, which enhance benzo(a)pyrene carcinogenicity on mouse skin, are used as hair dye components. It is not known whether such compounds will enhance the carcinogenicity of substituted aniline hair dye chemicals. The available epidemiologic data are not sufficient to link hair dye use with an increased incidence in human cancer.

  9. 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.

  10. 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

  11. 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)

  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. Components of Attention in Synesthesia

    DEFF Research Database (Denmark)

    Sørensen, Thomas Alrik; Nordfang, Maria; Pedersen, Michael Nygaard;

    2013-01-01

    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...... presented in colors congruent with the synesthetic experience. On the other half of the trials, the letters and digits were presented in colors that were incongruent with the synesthetic experience. Components of attention were estimated separately for congruent and incongruent trials by fitting the data...

  14. 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...

  15. 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

  16. 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.

  17. 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.

  18. Quasar redshifts: the intrinsic component

    Science.gov (United States)

    Hansen, Peter M.

    2016-09-01

    The large observed redshift of quasars has suggested large cosmological distances and a corresponding enormous energy output to explain the brightness or luminosity as seen at earth. Alternative or complementary sources of redshift have not been identified by the astronomical community. This study examines one possible source of additional redshift: an intrinsic component based on the plasma characteristics of high temperature and high electron density which are believed to be present.

  19. 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 ...

  20. Midterm to long-term follow-up study after hybrid total hip arthroplasty%混合型初次全髋关节置换术后中远期随访研究

    Institute of Scientific and Technical Information of China (English)

    黄强; 沈彬; 杨静; 周宗科; 康鹏德; 裴福兴

    2012-01-01

    目的 回顾性分析混合型初次全髋关节置换术的临床和影像学疗效及其相关影响因素.方法 对1999年1月至2001年12月期间接受混合型初次全髋关节置换术治疗髓部疾病的患者126例(135髋)进行中远期随访.观察假体位置及其周围骨质变化,计算聚乙烯内衬磨损率.采用Kaplan-Meier方法估算假体10年生存率,以无菌性松动、单纯骨溶解病灶清除植骨术及翻修为随访终点.结果 共有79例(85髋)患者获得随访.以无菌性松动为随访终点,髋臼假体10生存率为97.6%,股骨假体10年生存率为100%;以无菌性松动、单纯骨溶解病灶清除植骨术为随访终点,髋臼假体生存率为95.2%,股骨假体生存率为98.8%.结论 混合型初次全髋关节置换术后假体中远期生存率令人满意;采用第3代骨水泥技术固定的股骨假体取得与现代非骨水泥假体相近的中远期生存率.%Objective To evaluate clinical and radiaographic results and influencing factors of hybrid total hip arthroplasty (THA).Methods Totally 126 patients ( 135 hips) from January 1999 to December 2001 accepted hybrid THA were followed up. Components migration, periprosthetic bone changes,the polyethylene wear rate were mcasured radiologically.Kaplan-Meier analysis was performed to evaluate the survivalship of the acetabular and femoral components. End point was obvious radiological loosening or revision either or both of the acetabular and femoral components for aseptic loosening,infection or osteolysis debridement surgery.Results A total of 79 cases (85 hips) had been given follow-up.Using rcvision as the end point,the survival rate of acetabular was 95.2%,cemented femoral components was 98.8%.Using loosening as the end point for failure,the survival rate of acetabular was 97.6%,cemented femoral components was 100%.Conclusions The hybrid total hip prothesis long-term survival rate was satisfactory,especially in the femoral side.As a

  1. 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...

  2. Component Control System for a Vehicle

    Science.gov (United States)

    Fraser-Chanpong, Nathan (Inventor); Spain, Ivan (Inventor); Dawson, Andrew D. (Inventor); Bluethmann, William J. (Inventor); Lee, Chunhao J. (Inventor); Vitale, Robert L. (Inventor); Guo, Raymond (Inventor); Waligora, Thomas M. (Inventor); Akinyode, Akinjide Akinniyi (Inventor); Reed, Ryan M. (Inventor)

    2016-01-01

    A vehicle includes a chassis, a modular component, and a central operating system. The modular component is supported by the chassis. The central operating system includes a component control system, a primary master controller, and a secondary master controller. The component control system is configured for controlling the modular component. The primary and secondary master controllers are in operative communication with the component control system. The primary and secondary master controllers are configured to simultaneously transmit commands to the component control system. The component control system is configured to accept commands from the secondary master controller only when a fault occurs in the primary master controller.

  3. Hydrocarbon components in carbonaceous meteorites

    Science.gov (United States)

    Kissin, Y. V.

    2003-05-01

    Currently, the presence of free n-alkanes and isoprenoid alkanes in carbonaceous meteorites is usually explained either by microbial contamination during the period between the meteorite fall and collection or by contamination from the environment of analytical laboratories and museums. The goal of this research was to repeat analysis of hydrocarbon components in meteorites and to investigate possible meteorite contamination routes discussed in the literature. Experimental analysis of free organic constituents in five carbonaceous meteorites by infrared spectroscopy (IR) and gas chromatographic (GC) methods confirmed the presence of extractable aliphatic components, n-alkanes in the C 15H 32-C 27H 56 range and isoprenoid alkanes (phytane, pristane, and norpristane), in some of these meteorites. The contents of these compounds vary depending on the source. Insoluble organic components of two meteorites (meteorite kerogens) were isolated, and their composition was analyzed by IR and cracking/GC methods. Comparison with the data on several terrestrial contamination sources proposed in the literature shows that the presence of free saturated hydrocarbons in meteorites and the composition of the meteorite kerogen could not be explained either by microbial contamination or by contamination from the laboratory environment. The types of the hydrocarbons in meteorites resemble those typical of ancient terrestrial deposits of organic-rich sediments, except for the absence of lighter hydrocarbons, which apparently slowly evaporated in space, and multi-ring naphthenic compounds of the biologic origin, steranes, terpanes, etc. The prevailing current explanation for the presence of free linear saturated hydrocarbons in carbonaceous meteorites, apart from contamination, is the abiotic route from hydrogen and carbon monoxide. However, the data on the structure of meteorite kerogens require a search for different routes that initially produce complex polymeric structures containing

  4. 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...

  5. 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...... 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...

  6. 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

  7. 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.

  8. Components of Adenovirus Genome Packaging

    Science.gov (United States)

    Ahi, Yadvinder S.; Mittal, Suresh K.

    2016-01-01

    Adenoviruses (AdVs) are icosahedral viruses with double-stranded DNA (dsDNA) genomes. Genome packaging in AdV is thought to be similar to that seen in dsDNA containing icosahedral bacteriophages and herpesviruses. Specific recognition of the AdV genome is mediated by a packaging domain located close to the left end of the viral genome and is mediated by the viral packaging machinery. Our understanding of the role of various components of the viral packaging machinery in AdV genome packaging has greatly advanced in recent years. Characterization of empty capsids assembled in the absence of one or more components involved in packaging, identification of the unique vertex, and demonstration of the role of IVa2, the putative packaging ATPase, in genome packaging have provided compelling evidence that AdVs follow a sequential assembly pathway. This review provides a detailed discussion on the functions of the various viral and cellular factors involved in AdV genome packaging. We conclude by briefly discussing the roles of the empty capsids, assembly intermediates, scaffolding proteins, portal vertex and DNA encapsidating enzymes in AdV assembly and packaging. PMID:27721809

  9. Interpretable functional principal component analysis.

    Science.gov (United States)

    Lin, Zhenhua; Wang, Liangliang; Cao, Jiguo

    2016-09-01

    Functional principal component analysis (FPCA) is a popular approach to explore major sources of variation in a sample of random curves. These major sources of variation are represented by functional principal components (FPCs). The intervals where the values of FPCs are significant are interpreted as where sample curves have major variations. However, these intervals are often hard for naïve users to identify, because of the vague definition of "significant values". In this article, we develop a novel penalty-based method to derive FPCs that are only nonzero precisely in the intervals where the values of FPCs are significant, whence the derived FPCs possess better interpretability than the FPCs derived from existing methods. To compute the proposed FPCs, we devise an efficient algorithm based on projection deflation techniques. We show that the proposed interpretable FPCs are strongly consistent and asymptotically normal under mild conditions. Simulation studies confirm that with a competitive performance in explaining variations of sample curves, the proposed FPCs are more interpretable than the traditional counterparts. This advantage is demonstrated by analyzing two real datasets, namely, electroencephalography data and Canadian weather data.

  10. 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

  11. The components of paraphrase evaluations.

    Science.gov (United States)

    McCarthy, Philip M; Guess, Rebekah H; McNamara, Danielle S

    2009-08-01

    Two sentences are paraphrases if their meanings are equivalent but their words and syntax are different. Paraphrasing can be used to aid comprehension, stimulate prior knowledge, and assist in writing-skills development. As such, paraphrasing is a feature of fields as diverse as discourse psychology, composition, and computer science. Although automated paraphrase assessment is both commonplace and useful, research has centered solely on artificial, edited paraphrases and has used only binary dimensions (i.e., is or is not a paraphrase). In this study, we use an extensive database (N=1,998) of natural paraphrases generated by high school students that have been assessed along 10 dimensions (e.g., semantic completeness, lexical similarity, syntactical similarity). This study investigates the components of paraphrase quality emerging from these dimensions and examines whether computational approaches can simulate those human evaluations. The results suggest that semantic and syntactic evaluations are the primary components of paraphrase quality, and that computationally light systems such as latent semantic analysis (semantics) and minimal edit distances (syntax) present promising approaches to simulating human evaluations of paraphrases.

  12. 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.)

  13. 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

  14. Stochastic Modeling Of Wind Turbine Drivetrain Components

    DEFF Research Database (Denmark)

    Rafsanjani, Hesam Mirzaei; Sørensen, John Dalsgaard

    2014-01-01

    reliable components are needed for wind turbine. In this paper focus is on reliability of critical components in drivetrain such as bearings and shafts. High failure rates of these components imply a need for more reliable components. To estimate the reliability of these components, stochastic models...... are needed for initial defects and damage accumulation. In this paper, stochastic models are formulated considering some of the failure modes observed in these components. The models are based on theoretical considerations, manufacturing uncertainties, size effects of different scales. It is illustrated how...... the stochastic models can be used to obtain estimates of failure rates for wind turbine components....

  15. 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...

  16. The magnet components database system

    Energy Technology Data Exchange (ETDEWEB)

    Baggett, M.J. (Brookhaven National Lab., Upton, NY (USA)); Leedy, R.; Saltmarsh, C.; Tompkins, J.C. (Superconducting Supercollider Lab., Dallas, TX (USA))

    1990-01-01

    The philosophy, structure, and usage MagCom, the SSC magnet components database, are described. The database has been implemented in Sybase (a powerful relational database management system) on a UNIX-based workstation at the Superconducting Super Collider Laboratory (SSCL); magnet project collaborators can access the database via network connections. The database was designed to contain the specifications and measured values of important properties for major materials, plus configuration information (specifying which individual items were used in each cable, coil, and magnet) and the test results on completed magnets. These data will facilitate the tracking and control of the production process as well as the correlation of magnet performance with the properties of its constituents. 3 refs., 10 figs.

  17. 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.

  18. 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...

  19. 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.

  20. 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)

  1. 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...

  2. 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)

  3. 各种髋臼重建术治疗先天性髋关节脱位的评价(附261例报告)%Experience and Evaluation of Various Acetabular Recosnstructions in the Treatment of Congenital Dislocation of the Hip

    Institute of Scientific and Technical Information of China (English)

    彭明惺; 胡廷泽; 陈绍基; 周锡华; 韦福康; 周素华

    1985-01-01

    From 1961 to 1983,various acetabular reconstructions were performed in 261 cases for 308 affected hips.The patients aged between 11/2 and 13 years.Salter Innomlnate osteotomy should be given priority on those at proper age,yet it cannot substitute other reconstruction operations.Perlcapsular illae osteotomy of Pemberton is indlctaed on those having a shallow acetabulum.However,serious incongruity between head and acetabulum and/or posterior dislocation are contraindications for the above mentioned operations.Shelf-acetabuloplasty works well for the reconstruction of the lateral edge of aceta bulum.When above-mentioned operations prove impossible,medial displacement osteostomy of the pelvis by Chlarl or capsular arthro plasty by Colonna become the chief salvage procedure.As any operation has its advantages and limitations,a good pediatric surgeon should possess the ability to choose the most appropriate operation.An operation based on the surgeon's personal preference or habit often lead to failure.%@@ 现将我院从1961年4月至1983年10月,应用各种髋臼重建手术治疗先天性髋关节位的体会总结如下.

  4. 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%.

  5. 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.

  6. Model Of Reconfiguration In Component Environments

    Directory of Open Access Journals (Sweden)

    Jakub Grzesiak

    2015-01-01

    Full Text Available The significance of the component-based software and component platforms has increased in the last 20 years. To achieve full flexibility there is a need of reconfiguration process, which allows to change parameters of system without rebuilding or restarting it. In terms of components such a process should be executed with extraordinary care as contracts between components have to be preserved. In this article model of reconfiguration and roles of the components, which are used in the process, are proposed. Provided solution is quite general and could be applied to many of component platforms.

  7. Genetic components of vocal learning.

    Science.gov (United States)

    Scharff, Constance; White, Stephanie A

    2004-06-01

    Vocal learning is a rare trait. Humans depend on vocal learning to acquire spoken language, but most species that communicate acoustically have an innate repertoire of sounds that they use for information exchange. Among the few non-human species that also rely on vocal learning, songbirds have provided by far the most information for understanding this process. This article concentrates on the genetic components of vocal learning in humans and birds. We summarize the existing evidence for a genetic predisposition towards acquiring the species-specific human and avian vocal repertoires. We describe the approaches used for finding genes involved in shaping the neural circuitry required for vocal learning or in mediating the learning process itself. Special attention is given to a particular gene, FOXP2, which has been implicated in a human speech and language disorder. We have studied FoxP2 in avian vocal learners and non-learners and review evidence that links both the molecule and its close homologue FoxP1 to the development of brain regions implicated in vocal learning and to their function. FoxP2 has a characteristic expression pattern in a brain structure uniquely associated with learned vocal communication, Area X in songbirds, or its analogue in parrots and hummingbirds. In both avian song learners and non-learners FoxP2 expression predominates in sensory and sensory-motor circuits. These latter regions also express FoxP2 in mammals and reptiles. We conclude that FoxP2 is important for the building and function of brain pathways including, but not limited to, those essential for learned vocal communication. PMID:15313783

  8. Tengi Interfaces for Tracing between Heterogeneous Components

    DEFF Research Database (Denmark)

    Pfeiffer, Rolf-Helge; Wasowski, Andrzej

    2012-01-01

    for the definition of software components containing heterogeneous artifacts. Tengi interfaces link components containing different textual and visual software development artifacts ranging from high-level specification documents to low-level implementation documents. We formally define and implement Tengi...

  9. 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...

  10. 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.

  11. 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.

  12. 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.

  13. 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...

  14. Direct UV-written integrated optical components

    DEFF Research Database (Denmark)

    Svalgaard, Mikael

    2004-01-01

    Direct UV writing is an emerging method for flexible, low cost fabrication of integrated optical waveguides and components. The performance of UV written components can be similar to that achieved with more elaborate fabrication techniques.......Direct UV writing is an emerging method for flexible, low cost fabrication of integrated optical waveguides and components. The performance of UV written components can be similar to that achieved with more elaborate fabrication techniques....

  15. 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...

  16. 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)

  17. 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

  18. 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.

  19. 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...

  20. 21 CFR 890.3920 - Wheelchair component.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wheelchair component. 890.3920 Section 890.3920...) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3920 Wheelchair component. (a) Identification. A wheelchair component is a device intended for medical purposes that...