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Sample records for cementless acetabular components

  1. Early results of the use of oblong S-ROM cementless acetabular component

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    Popović Zoran

    2003-01-01

    Full Text Available Massive deficiency of acetabular bone stock is a challenging problem in the increasing number of patients who need a revision of the failed hip arthroplasty. Oblong acetabular cup has been presented as an alternative reconstruction technique for hips with extensive acetabular bone loss. The aim of this study was to present our results with the use of a bilobed acetabular component inserted during revisional surgery, to define indications, and to introduce this method into our orthopaedic practice. Seven patients underwent revisional hip arthroplasty with a cementless oblong acetabular component between September 2000 and June 2002. Six patients underwent revisional hip arthroplasty, and in one primary hip arthroplasty by oblong acetabular component was performed because of bone defect of acetabulum after gunshot fracture. The average follow up was thirteen months. Radiographic analysis in all patients demonstrated stable bone incorporated acetabular component with the restored hip. All the patients walked with full weight bearing and were without pain. On the basis of our experience we find this method statisfactory in certain types of bone defefects of acetabulum, and that it provides stable reconstruction of acetabulum with the correction of hip joint.

  2. Cementless acetabular fixation in patients 50 years and younger at 10 to 18 years of follow-up.

    Science.gov (United States)

    Teusink, Matthew J; Callaghan, John J; Warth, Lucian C; Goetz, Devon D; Pedersen, Douglas R; Johnston, Richard C

    2012-08-01

    The purpose of the study was to evaluate the 10- to 18-year follow-up of cementless acetabular fixation in patients 50 years and younger. We retrospectively reviewed a consecutive group of 118 patients (144 hips) in whom primary total hip arthroplasty had been performed by 2 surgeons using a cementless acetabular component. Two (1.4%) cementless acetabular components were revised because of aseptic loosening. Twenty-four hips (16.7%) were revised for any mechanical failure of the acetabular component mostly related to acetabular liner wear and osteolysis. The average linear wear rate was 0.19 mm per year, which was higher than our previous reports with cemented acetabular fixation. The fiber mesh ingrowth surface of the cementless acetabular component in this study was superior to cemented acetabular components in terms of fixation. However, the high rates of wear and osteolysis have led to poor overall acetabular component construct survivorship.

  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. Optimization of acetabular component orientation using DOE

    Science.gov (United States)

    Krepelka, Mircea; Toth-Taşcǎu, Mirela

    2012-09-01

    Stress shielding is increasingly recognized as an important cause of acetabular component failure. Several studies have been focused on improving the acetabular component placement to reduce the risk of dislocation, impingement and range of motion but little is known of its influence on implant-bone interface pressures. This study employs experimental design, 3D reconstruction and FE simulation to identify the most significant factors for acetabular component behavior and predict the best configuration of acetabular spatial orientation angles within the constraints of the Lewinnek's safe zone in order to minimize peak contact pressures. Data analysis by response surface method revealed that the magnitude of periacetabular pressures was significantly reduced by the anteversion angle at its lowest value as well as the abduction angle located at the central point value, which corresponded to a 40° abduction and 5° anteversion of cup orientation.

  8. CUSTOMIZED ACETABULAR COMPONENTS IN REVISION HIP ARTHROPLASTY

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    G. M. Kavalersky

    2016-01-01

    Full Text Available In recent years, there is a trend of increasing demand for revision hip arthroplasty. Among these patients there are many with complex acetabular defects, including patients with pelvic discontinuity. To ensure stability for revised acetabular components in such cases becomes a challenging or unachievable task. Such defects give indications for printing customized tri-flange acetabular component. The authors analysed own experience of creating and applying custom made acetabular components in 3 patients with complex acetabular defects. Material and methods. Among the patients there were 2 women and 1 man. Average age was 60,3±19,4 years (38 to 78 years. Two patients had III B defects with pelvic discontinuity and one patient had III A defect by Paprosky classification. As the first step, the authors in collaboration with engineers printed a plaster full size pelvic 3D model, as the second step a customized tri-flange acetabular component was designed and printed. Harris Hip Score was evaluated preoperatively and 3 months postoperatively. Results. Average follow-up period was 5,3±2,5 months (3 to 8 months. The authors observed no cases of implant loosening, dislocation or deep periprosthetic infection. Average Harris Hip Score before surgery was 27,13 and after surgery – 74,1 indicating a significant improvement in 3 months postoperatively. Conclusion. Indications for use of individual acetabular components in reported patients correspond to indications formulated by Berasi et al. The authors obtained encouraging early follow-up outcomes that correspond to data of other authors. In one patient certain difficulties were reported due to insufficient pelvic distraction. Component’s flanges prevented achieving adequate pelvic distraction. Nevertheless, good primary stability was achieved. Modern software and 3D metal printers can significantly reduce the production cost of customized acetabular components. Application of this technology can be

  9. A randomised controlled trial of cemented and cementless femoral components for metal-on-metal hip resurfacing: a bone mineral density study.

    Science.gov (United States)

    Tice, A; Kim, P; Dinh, L; Ryu, J J; Beaulé, P E

    2015-12-01

    The primary purpose of this study of metal-on-metal (MoM) hip resurfacing was to compare the effect of using a cementless or cemented femoral component on the subsequent bone mineral density (BMD) of the femoral neck. This was a single-centre, prospective, double-blinded control trial which randomised 120 patients (105 men and 15 women) with a mean age of 49.4 years (21 to 68) to receive either a cemented or cementless femoral component. Follow-up was to two years. Outcome measures included total and six-point region-of-interest BMD of the femoral neck, radiological measurements of acetabular inclination, neck-shaft and stem-shaft angles, and functional outcome scores including the Harris hip score, the Western Ontario and McMaster Universities Osteoarthritis Index and the University of California at Los Angeles activity scale. In total, 17 patients were lost to follow-up leaving 103 patients at two years. There were no revisions in the cementless group and three revisions (5%) in the cemented group (two because of hip pain and one for pseudotumour). The total BMD was significantly higher in the cementless group at six months (p < 0.001) and one year (p = 0.01) than in the cemented group, although there was a loss of statistical significance in the difference at two years (p = 0.155). All patient outcomes improved significantly: there were no significant differences between the two groups. The results show better preservation of femoral neck BMD with a cementless femoral component after two years of follow-up. Further investigation is needed to establish whether this translates into improved survivorship.

  10. 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.

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    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).

  11. 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.

  12. 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

  13. 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 arthrop...... should therefore take special care during placement of the acetabular component in patients with AD....

  14. Postmortem retrieved canine THR: femoral and acetabular component interaction.

    Science.gov (United States)

    Skurla, Carolyn P; James, Susan P

    2004-01-01

    Dogs are the preferred animal model for testing of human total hip replacements (THRs). A postmortem retrieval program for clinical, cemented, canine THR was established to analyze the long-term performance of THRs in dogs and to compare that performance to postmortem retrievals of human THRs. The purpose of the present study was to analyze the interaction between the femoral and acetabular components. Thirty-eight postmortem retrievals from 29 dogs were donated and analyzed. The acetabular components (ACs) were measured for volumetric wear and graded for articulating surface damage. Femoral and acetabular components were mechanically tested for implant stability. Digital image analysis was performed on contact radiographs of transverse femoral slices. Of 14 cases with a firmly implanted femoral component (FC). 6 articulated against loose ACs. Of 24 cases with a loose FC, 16 articulated against loose ACs. Only 4 specimens had both components firmly implanted, and 14 specimens had both components loose. There was a significant positive correlation between AC volumetric wear and FC loosening; however, there was no evidence of osteolysis or wear debris induced osteolysis as seen in human postmortem retrieval studies. There was a significant but weak negative correlation between FC loosening at the cement/bone interface and AC scores reflecting damage to the rim and creep across the entire AC. Although implant-on-implant damage to the AC was expected to positively correlate with FC loosening, this was not found. Researchers need to look at interactions between AC and FC to understand how the failure of one component affects performance of the other.

  15. 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

  16. Total Hip Arthroplasty Using Modular Trabecular Metal Acetabular Components for Failed Treatment of Acetabular Fractures: A Mid-term Follow-up Study

    Institute of Scientific and Technical Information of China (English)

    De-Yong Huang; Liang Zhang; Yi-Xin Zhou; Chun-Yu Zhang; Hui Xu; Yong Huang

    2016-01-01

    Background:Porous-coated cups have been widely used in acetabular reconstruction after failed treatment of acetabular fractures,and good results have been reported with the use of these cups;however,the durability and functionality of modular trabecular metal (TM) acetabular components in acetabular reconstruction after failed treatment of acetabular fractures remain unclear.This study aimed to examine the radiographic and clinical outcomes associated with the use of modular TM acetabular components for failed treatment of acetabular fractures to assess the durability and functionality of these components in acetabular reconstruction after failed treatment of acetabular fractures.Methods:A total of 41 patients (41 hips) underwent total hip arthroplasty (THA) using modular TM acetabular components for failed treatment of acetabular fractures at our hospital between January 2007 and December 2012.Among these patients,two were lost to follow-up.Therefore,39 patients (39 hips) were finally included in this study.The Harris hip score before and after the surgery,satisfaction level of the patients,and radiographic results were assessed.Results:The mean Harris hip score increased from 34 (range,8-52) before surgery to 91 (range,22-100) at the latest follow-up examination (P < 0.001).The results were excellent for 28 hips,good for six,fair for three,and poor for two.Among the 39 patients,25 (64%) and 10 (26%) were very satisfied and somewhat satisfied,respectively.All cups were found to be fully incorporated,and no evidence of cup migration or periacetabular osteolysis was noted.Conclusions:Despite the technically demanding nature of the procedure,THA using modular TM acetabular components showed good durability and functionality and may be an effective reconstruction option for failed treatment of acetabular fractures.

  17. 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.

  18. A randomised controlled trial comparing highly cross-linked and contemporary annealed polyethylene after a minimal eight-year follow-up in total hip arthroplasty using cemented acetabular components.

    Science.gov (United States)

    Langlois, J; Atlan, F; Scemama, C; Courpied, J P; Hamadouche, M

    2015-11-01

    Most published randomised controlled trials which compare the rates of wear of conventional and cross-linked (XL) polyethylene (PE) in total hip arthroplasty (THA) have described their use with a cementless acetabular component. We conducted a prospective randomised study to assess the rates of penetration of two distinct types of PE in otherwise identical cemented all-PE acetabular components. A total of 100 consecutive patients for THA were randomised to receive an acetabular component which had been either highly XL then remelted or moderately XL then annealed. After a minimum of eight years follow-up, 38 hips in the XL group and 30 hips in the annealed group had complete data (mean follow-up of 9.1 years (7.6 to 10.7) and 8.7 years (7.2 to 10.2), respectively). In the XL group, the steady state rate of penetration from one year onwards was -0.0002 mm/year (sd 0.108): in the annealed group it was 0.1382 mm/year (sd 0.129) (Mann-Whitney U test, p XLPE cemented acetabular component.

  19. 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.

  20. 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.

  1. 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...

  2. 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...

  3. 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.

  4. Digital tomosynthesis with metal artifact reduction for assessing cementless hip arthroplasty: a diagnostic cohort study of 48 patients

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    Tang, Hao; Yang, Dejin; Guo, Shengjie; Tang, Jing; Liu, Jian; Wang, Dacheng; Zhou, Yixin [Beijing Jishuitan Hospital, Fourth Clinical College of Peking University, Department of Orthopaedic Surgery, Beijing (China)

    2016-11-15

    For postoperative imaging assessment of cementless hip arthroplasty, radiography and computed tomography (CT) were restricted by overlapping structures and metal artifacts, respectively. A new tomosynthesis with metal artifact reduction (TMAR) is introduced by using metal extraction and ordered subset-expectation maximization (OS-EM) reconstruction. This study investigated the effectiveness of TMAR in assessing fixation stability of cementless hip arthroplasty components. We prospectively included 48 consecutive patients scheduled for revision hip arthroplasty in our hospital, with 41 femoral and 35 acetabular cementless components available for evaluation. All patients took the three examinations of radiography, CT, and TMAR preoperatively, with intraoperative mechanical tests, and absence or presence of osteointegration on retrieved prosthesis as reference standards. Three senior surgeons and four junior surgeons evaluated these images independently with uniform criteria. For TMAR, 82 % diagnoses on the femoral side and 84 % diagnoses on the acetabular side were accurate. The corresponding values were 44 and 67 % for radiography, and 39 % and 74 % for CT. Senior surgeons had significantly higher accuracy than junior surgeons by radiography (p < 0.05), but not by TMAR or CT. By minimizing metal artifacts in the bone-implant interface and clearly depicting peri-implant trabecular structures, the TMAR technique improved the diagnostic accuracy of assessing fixation stability of cementless hip arthroplasty, and shortened the learning curve of less experienced surgeons. Level II, diagnostic cohort study. (orig.)

  5. 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

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

    OpenAIRE

    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 glenoid implant. A 3D finite element model of a complete scapula was used to quantify the effect of a dysfunctional rotator cuff in terms of bone-implant interface micromotions when the implant is ph...

  7. Clinical and radiological outcome of the cemented Contemporary acetabular component in patients < 50 years of age.

    Science.gov (United States)

    Schmitz, M W J L; Timmer, C; Rijnen, W H C; Gardeniers, J W M; Schreurs, B W

    2013-12-01

    Despite the worldwide usage of the cemented Contemporary acetabular component (Stryker), no published data are available regarding its use in patients aged Contemporary acetabular component with the Exeter cemented stem between January 1999 and January 2006. There were 152 hips in 126 patients, 61 men and 65 women, mean age at surgery 37.6 years (16 to 49 yrs). One patient was lost to follow-up. Mean clinical follow-up of all implants was 7.6 years (0.9 to 12.0). All clinical questionnaire scores, including Harris hip score, Oxford hip score and several visual analogue scales, were found to have improved. The eight year survivorship of all acetabular components for the endpoints revision for any reason or revision for aseptic loosening was 94.4% (95% confidence interval (CI) 89.2 to 97.2) and 96.4% (95% CI 91.6 to 98.5), respectively. Radiological follow-up was complete for 146 implants. The eight year survival for the endpoint radiological loosening was 93.1% (95% CI 86.2 to 96.6). Three surviving implants were considered radiologically loose but were asymptomatic. The presence of acetabular osteolysis (n = 17, 11.8%) and radiolucent lines (n = 20, 13.9%) in the 144 surviving cups indicates a need for continued observation in the second decade of follow-up in order to observe their influence on long-term survival. The clinical and radiological data resulting in a ten-year survival rate > 90% in young patients support the use of the Contemporary acetabular component in this specific patient group.

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

    Directory of Open Access Journals (Sweden)

    G. García del Pino

    2002-01-01

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

  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...... osteolysis associated with a deep infection, but no signs of proximal loosening. 3 femora had areas of minor proximal osteolysis. 16 acetabular components (14 threaded) had been revised in 13 patients. The average Harris hip score was 91 points at the latest follow-up. We conclude that the uncemented...... titanium femoral component with a circumferential porous coating performed well in these patients, most of whom were young. As reported previously, aseptic loosening of threaded acetabular components was common....

  10. Accuracy of methods to measure femoral head penetration within metal-backed acetabular components.

    Science.gov (United States)

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

    2016-06-30

    A number of different software programs are used to investigate the in vivo wear of polyethylene bearings in total hip arthroplasty. With wear rates below 0.1 mm/year now commonly being reported for highly cross-linked polyethylene (XLPE) components, it is important to identify the accuracy of the methods used to measure such small movements. The aims of this study were to compare the accuracy of current software programs used to measure two-dimensional (2D) femoral head penetration (FHP) and to determine whether the accuracy is influenced by larger femoral heads or by different methods of representing the acetabular component within radiostereometric analysis (RSA). A hip phantom was used to compare known movements of the femoral head within a metal-backed acetabular component to FHP measured radiographically using RSA, Hip Analysis Suite (HAS), PolyWare, Ein Bild Roentgen Analyse (EBRA), and Roentgen Monographic Analysis Tool (ROMAN). RSA was significantly more accurate than the HAS, PolyWare, and ROMAN methods when measuring 2D FHP with a 28 mm femoral head. Femoral head size influenced the accuracy of HAS and ROMAN 2D FHP measurements, EBRA proximal measurements, and RSA measurements in the proximal and anterior direction. The use of different acetabular reference segments did not influence accuracy of RSA measurements. The superior accuracy and reduced variability of RSA wear measurements allow much smaller cohorts to be used in RSA clinical wear studies than those utilizing other software programs. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

  11. Measuring acetabular component position on lateral radiographs - ischio-lateral method.

    Science.gov (United States)

    Pulos, Nicholas; Tiberi Iii, John V; Schmalzried, Thomas P

    2011-01-01

    The standard method for the evaluation of arthritis and postoperative assessment of arthroplasty treatment is observation and measurement from plain films, using the flm edge for orientation. A more recent employment of an anatomical landmark, the ischial tuberosity, has come into use as orientation for evaluation and is called the ischio-lateral method. In this study, the use of this method was evaluated as a first report to the literature on acetabular component measurement using a skeletal reference with lateral radiographs. Postoperative radiographs of 52 hips, with at least three true lateral radiographs taken at different time periods, were analyzed. Component position was measured with the historical method (using the flm edge for orientation) and with the new method using the ischio-lateral method. The mean standard deviation (SD) for the historical approach was 3.7° and for the ischio-lateral method, 2.2° (p historical method, 19 (36.5%) hips had a SD greater than ± 4°, compared to six hips (11.5%) with the ischio-lateral method. By using a skeletal reference, the ischio-lateral method provides a more consistent measurement of acetabular component position. The high intra-class correlation coefficients for both intra- and inter-observer reliability indicate that the angle measured with this simple method, which employs no further technology, increased time, or cost, is consistent and reproducible for multiple observers.

  12. 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

  13. 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.

  14. DUAL MOBILITY ACETABULAR COMPONENT AS A WAY TO PREVENT HEAD DISLOCATION OF THE HIP

    Directory of Open Access Journals (Sweden)

    V. A. Shilnikov

    2016-01-01

    Full Text Available Prevention of femoral head dislocation is becoming one of the most important tasks in view of increased number of total hip replacement procedures throughout the world. The purpose of the present work is to acquaint the surgeons with possibilities and the first experience of dual mobility acetabular component application as the most up-to-date solution to prevent dislocation of the femoral head in primary or revision arthroplasties. The paper is based on the literature data and presents a critical analysis of the causes of femoral head dislocation during hip replacement. The authors considered historical aspects and the first outcomes of dual mobility use in the European and Western countries, as well as own positive clinical experience with dual mobility system during a study of 36 patients with an increased risk of femoral head dislocation.

  15. Polyethylene and metal debris generated by non-articulating surfaces of modular acetabular components.

    Science.gov (United States)

    Huk, O L; Bansal, M; Betts, F; Rimnac, C M; Lieberman, J R; Huo, M H; Salvati, E A

    1994-07-01

    We report a prospective study of the liner-metal interfaces of modular uncemented acetabular components as sources of debris. We collected the pseudomembrane from the screw-cup junction and the empty screw holes of the metal backing of 19 acetabula after an average implantation of 22 months. Associated osteolytic lesions were separately collected in two cases. The back surfaces of the liners and the screws were examined for damage, and some liners were scanned by electron microscopy. The tissues were studied histologically and by atomic absorption spectrophotometry to measure titanium content. The pseudomembrane from the screw-cup junction contained polyethylene debris in seven specimens and metal debris in ten. The material from empty screw holes was necrotic tissue or dense fibroconnective tissue with a proliferative histiocytic infiltrate and foreign-body giant-cell reaction. It contained polyethylene debris in 14 cases and metal in five. The two acetabular osteolytic lesions also showed a foreign-body giant-cell reaction to particulate debris. The average titanium levels in pseudomembranes from the screw-cup junction and the empty screw holes were 959 micrograms/g (48 to 11,900) and 74 micrograms/g (0.72 to 331) respectively. The tissue from the two lytic lesions showed average titanium levels of 139 and 147 micrograms/g respectively. The back surfaces of the PE liners showed surface deformation, burnishing, and embedded metal debris. All 30 retrieved screws demonstrated fretting at the base of the head and on the proximal shaft. Non-articular modular junctions create new interfaces for the generation of particulate debris, which may cause granulomatous reaction.

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

    Science.gov (United States)

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

    2011-03-01

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

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    ) and 2 years (range, 0-16 years), respectively. Survival of first revision THA, with second revision of the femur as outcome, was evaluated using hazard ratios (HRs) with 95% confidence interval (CI) adjusting for potential confounding. All patient- and surgery-related data are collected from Danish...... medical databases. Recording of bone defects in the DHR is based on surgeons' intraoperative findings. With the numbers studied, we found no differences in the risk of second revision between the overall cohort between cementless and cemented techniques (HR, 1.32; 95% CI, 0.97-1.80; p = 0.076); however...... for the most likely confounding factors. Our data suggest that increased use of cementless fixation in primary THA may lead to inferior survivorship of first revision THA. Level III, therapeutic study....

  18. 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.

  19. Long-term outcome of a metal-on-polyethylene cementless hip resurfacing.

    Science.gov (United States)

    Tan, Timothy L; Ebramzadeh, Edward; Campbell, Patricia A; Al-Hamad, Mariam; Amstutz, Harlan C

    2014-04-01

    Due to the well-documented problems surrounding metal-on-metal bearings, the use of hip resurfacing has declined. Since the potential benefits of hip resurfacing remain desirable, it may be beneficial to investigate the long-term outcome of hip resurfacings using metal-on-polyethylene in the 1980's. We report the long-term survivorship and modes of failure of a cementless metal-on-polyethylene resurfacing (n = 178) with different porous ingrowth surfaces. While acetabular loosening was absent, a high incidence of femoral failures (femoral loosening = 18.1%, osteolytic neck fracture = 21%) occurred despite using the same ingrowth surface for both components. Ongoing developments using the lessons learned from these previous generation components and utilizing modern low wear materials, e.g., cross-linked polyethylene, may lead to improved implants for future hip resurfacings.

  20. Cross-sectional Anatomy of Ilium for Guiding Acetabular Component Placement Using High Hip Center Technique in Asian Population

    Institute of Scientific and Technical Information of China (English)

    Jian-Lin Xiao; Jian-Lin Zuo; Peng Liu; Yan-Guo Qin; Xue-Zhou Li; Tong Liu; Zhong-Li Gao

    2015-01-01

    Background:Many clinical studies have been published involving the use of a high hip center (HHC),achieved good follow-up.However,there is a little anatomic guidance in the literature regarding the amount of bone stock available for initial implant coverage in this area of the ilium.The purpose of this study was to evaluate the thickness and width of the human ilium and related acetabular cup coverage for guiding acetabular component placement in HHC.Methods:A total of 120 normal hips in 60 cases of adult patients from lower extremities computer tomographic angiography Digital Imaging and Communications in Medicine data were chosen for the study.After importing the data to the mimics software,we chose the cross sections every 5-mm increments from the rotational center of the hip to the cephalic of the ilium according the body sagittal axis,then we measured the thickness and width of the ilium for each cross section in axial plane,calculated the cup coverage at each chosen section.Results:At the acetabular dome,the mean thickness and width of the ilium were 49.71 ± 4.88 mm and 38.92 ± 3.67 mm,respectively,whereas at 1 cm above the dome,decreased to 41.35 ± 5.13 and 31.13 ± 3.37 respectively,and 2 cm above the dome,decreased to 31.25 ± 4.04 and 26.65 ± 3.43,respectively.Acetabular cup averaged coverage for 40-,50-,and 60-mm hemispheric shells,was 100%,89%,and 44% at the acetabular dome,100%,43.7%,and 27.5% for 1 cm above the dome,and 37.5%,21.9%,and 14.2% for 2 cm above the dome.Conclusions:HHC reconstructions within l cm above the acetabular dome will be an acceptable and smaller diameter prosthesis would be better.

  1. Wear of the polyethylene liner-metallic shell interface in modular acetabular components. An in vitro analysis.

    Science.gov (United States)

    Lieberman, J R; Kay, R M; Hamlet, W P; Park, S H; Kabo, J M

    1996-08-01

    The purpose of this study was to determine the effect of compression cycles and wear patterns on the polyethylene liner-metallic shell interface in modular acetabular components. Articular frictional torque was also measured. Modular acetabular components from five manufacturers were tested. The polyethylene liners were sputter coated with gold on the convex surface to enhance the visualization of wear and deformation patterns. Each component was cycled for 10 million cycles in a hydraulic fatigue testing machine. Frictional torque was measured prior to the start of the cyclic loading and in increments of 2 million cycles. Frictional torque was significantly lower in the design with an enhanced polyethylene liner. Abrasion of the gold from the convex surface of polyethylene liners varied from 2 to 23% between designs. Extrusion of the polyethylene into the screw holes in the metallic shells was universal. Three modes of damage (burnishing, punch-out, and gouging) were identified on the convex surface of the polyethylene liner. Abrasion of the gold from the convex surface of the polyethylene varied greatly between designs. This is indicative of relative motion between the polyethylene liner and the metallic shell. This motion must be minimized to limit the generation of wear debris from the convex surface of the polyethylene. Several aspects of modular acetabular component design could be implemented to potentially reduce wear, including limiting the number of holes available for screw placement, smoothing out the edges of the screw holes to avoid punch-out, and avoiding supplemental fixation of the liner unless it is essential to prevent motion between the liner and the metallic shell.

  2. 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

  3. 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.

  4. 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.

  5. To Compare Time-Weighted Graphs to Evaluate the Inclination of the Acetabular Component of Patients Who Had Total Hip Replacement Surgery

    Directory of Open Access Journals (Sweden)

    Leman Tomak

    2015-01-01

    Full Text Available Time-weighted graphs are used to detect small shifts in statistical process control. The aim of this study is to evaluate the inclination of the acetabular component with CUmulative SUM (CUSUM chart, Moving Average (MA chart, and Exponentially Weighted Moving Average (EWMA chart. The data were obtained directly from thirty patients who had undergone total hip replacement surgery at Ondokuz Mayis University, Faculty of Medicine. The inclination of the acetabular component of these people, after total hip replacement, was evaluated. CUSUM chart, Moving Average chart, and Exponentially Weighted Moving Average were used to evaluate the quality control process of acetabular component inclination. MINITAB Statistical Software 15.0 was used to generate these control charts. The assessment done with time-weighted charts revealed that the acetabular inclination angles were settled within control limits and the process was under control. It was determined that the change within the control limits had a random pattern. As a result of this study it has been obtained that time-weighted quality control charts which are used mostly in the field of industry can also be used in the field of medicine. It has provided us with a faster visual decision.

  6. 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.).

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

    OpenAIRE

    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...

  8. [Acetabular fractures].

    Science.gov (United States)

    Gänsslen, A; Oestern, H J

    2011-12-01

    Treatment of acetabular fractures requires extensive knowledge of the bony anatomy, the amount of possible exposure of the bone with the selected approaches and fracture type-dependent indications of operative treatment. Classification of the fracture with detailed analysis of the fracture morphology is the basis for decision making and planning. The primary treatment aim is the anatomic reconstruction of the acetabulum which results in optimal long-term results.The basis of this overview is the presentation of standard treatment concepts in acetabular fracture surgery. Beside characteristics of the acetabular bony anatomy, biomechanical and pathomechanical principles and the relevant radiological anatomy, the treatment options, both conservative and operative and basic principles of the indications for standard surgical approaches will be discussed.The special fracture type is discussed in detail regarding incidence, injury mechanism, concomitant injuries, options for conservative and operative treatment, quality of operative reduction and long-term results.Furthermore, epidemiological data on typical postoperative complications are evaluated.

  9. 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.

  10. 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.

  11. 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.

  12. Backside nonconformity and locking restraints affect liner/shell load transfer mechanisms and relative motion in modular acetabular components for total hip replacement.

    Science.gov (United States)

    Kurtz, S M; Ochoa, J A; White, C V; Srivastav, S; Cournoyer, J

    1998-05-01

    Nonconformity between the polyethylene liner and the metal shell may exist in modular acetabular components by design, due to manufacturing tolerances, or from locking mechanisms that attach the polyethylene liner to the metal shell. Relative motion at the liner/shell interface has been associated with backside wear, which may contribute to osteolysis which has been clinically observed near screw holes. The purpose of this study was to investigate the effect of nonconformity and locking restraints on the liner/shell relative motion and load transfer mechanisms in a commercially available, metal-backed acetabular component with a polar fenestration. The finite element method was used to explore the hypothesis that backside nonconformity and locking restraints play important roles in long-term surface damage mechanisms that are unique to modular components, such as backside wear and liner extrusion through screw holes. The three-body quasi-static contact problem was solved using a commercially available explicit finite element code, which modeled contact between the femoral head, polyethylene liner, and the metal shell. Four sets of liner boundary conditions were investigated: no restraints, rim restraints, equatorial restraints, and both rim and equatorial restraints. The finite element model with a conforming shell predicted between 8.5 and 12.8 microm of incremental extrusion of the polyethylene through the polar fenestration, consistent with in vitro experiments of the same design under identical loading conditions. Furthermore, idealized rim and/or equatorial liner restraints were found to share up to 71% of the load across the liner/shell interface. Consequently, the results of this study demonstrate that backside nonconformity and locking restraints substantially influence backside relative motion as well as load transfer at the liner/shell interface.

  13. 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.

  14. 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.

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

    Science.gov (United States)

    Hedia, H S; El-Midany, T T; Shabara, M A N; Fouda, N

    2006-09-01

    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.

  16. 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.

  17. 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)...

  18. 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.)

  19. 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.

  20. Higher reliability of triple-phase bone scintigraphy in cementless total hip arthroplasty compared to cementless bipolar hemiarthroplasty

    Directory of Open Access Journals (Sweden)

    Burak Yoldas

    2016-09-01

    Conclusions: Due to the higher sensitivity, specificity and accuracy, TPBS has a more reliable diagnostic value for cementless THA in the diagnosis of periprosthetic infection compared to cementless BHA.

  1. 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

  2. Total hip arthroplasty using a cylindrical cementless stem in patients with a small physique.

    Science.gov (United States)

    Nakamura, Yoshihide; Mitsui, Hiromasa; Kikuchi, Akira; Toh, Satoshi; Katano, Hiroshi

    2011-01-01

    We performed total hip arthroplasty using an anatomic medullary locking cementless stem for small-physique patients from 1988 to 1995. We conducted a retrospective study of 50 joints in 44 cases, including 40 developmentally dysplastic hips followed for 12 to 20 years (average, 15.1 years). Average height and body weight were 152 cm and 56 kg (5.0 ft and 124 lb), respectively, with an average body mass index of 24.2. Twelve joints (24%) were revised for acetabular-sided failures. Forty-eight stems (96%) showed bone ingrowth fixation, and there were no unstable stems. The simple cylindrical shape of the distal portion of the AML stem was less affected by deformity of the proximal femur of developmental dysplasia of the hip in patients with a small physique, and both clinically and radiologically good results were confirmed at long-term follow-up.

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

    Science.gov (United States)

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

    2009-09-01

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

  4. Use of trabecular metal acetabular component in total hip arthroplasty performed on patients with residual poliomyelitis%骨小梁金属髋臼杯在脊髓灰质炎后遗症患者非瘫痪侧全髋关节置换术中的应用

    Institute of Scientific and Technical Information of China (English)

    王波; 李晓华; 赵辉; 姜晨轶; 彭松

    2015-01-01

    Objective To assess the short-term clinical outcomes of the patients with residual poliomyelitis who underwent cementless total hip arthroplasty ( THA ) using trabecular metal ( TM ) acetabular component on their nonparalytic limbs.Methods From January 2014 to January 2015, five patients with residual poliomyelitis ( five hips, nonparalytic contralateral limbs) underwent THA using TM acetabular component at the femoral prosthesis. The acetabular prosthesis position was determined preoperatively by the standard of 40°-45°for the inclination and 10°for the anteversion.Harris hip scores, complications, and range of motion ( ROM) of the joints were determined by chart review and confirmed by questionnaire and examination before the surgery, one week and six weeks after the surgery and during the follow-up; the radiographs of bilateral hips and full-length lower limbs were taken six weeks after the surgery, which were reviewed by two observers.Follow-up was available for all the five patients at a minimum duration of one year.A descriptive method was used to compare the difference of each time point.Results All the patients had pain relief and improvement in the hip function; the mean Harris hip score improved from (63.0 ±6.7) preoperatively to (82.6 ±1.5) postoperatively, and (92.5 ± 1.3) at the last follow-up (P<0.05).No complication occured.There was no loosening or osteolysis in this series.The average ranges of hip motions were as follows: six weeks after surgery, flexion (75.3 ± 9.5)°, extension (5.6 ±3.2)°, abduction (10.3 ±3.9)°, adduction (15.8 ±3.4)°; three months later, flexion (91.2 ±5.6)°, extension (10.5 ±2.6)°, abduction (15.5 ±2.4)°, adduction (25.3 ± 2.7)°;at the last follow -up, flexion (92.6 ±6.9)°, extension (10.3 ±3.2)°, abduction (16.5 ± 4.5)°, adduction (29.3 ±3.1)°.Conclusions Cementless THA may be suitable for painful hips in adult patients with residual poliomyelitis.Nonetheless, these patients should be informed

  5. 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.

  6. 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.

  7. 人工全髋关节置换术中髋臼骨缺损的重建%Reconstruction of acetabular bone deficiency in total hip arthroplasty

    Institute of Scientific and Technical Information of China (English)

    杨波; 林进; 翁习生; 金今; 赵庆; 邱贵兴

    2009-01-01

    Objective To discuss the characteristics and reconstruction strategies of acetabular bone deficiency in total hip arthroplasty in order to find the optimal resolution for this clinical puzzle. Methods Clinical and radiological materials of 37 patients (37 hips) with acetabular deficiency who underwent primary or revision total hip arthreplasty were analyzed retrospectively from May 1998 to August 2008. According to the common classification system for acetabular bone deficiency-the AAOS classification system, the acetabular bone defect was reconstructed using morsellized or structural bone grafting, accessory acetabular hardware (ring, cup or cage) together with cemented or cementless acetabular component respectively. All patients were followed up regularly to assess their hip function improvement by measuring the Harris hip score and to find out the grafting bone healing, absorption and position of the prosthesis by plain radiographic examination. Results There were 11 primary and 26 revision total hip arthroplasty. There were 9 hips of AAOS-type Ⅰ defect, 13 of type Ⅱ and 15 of type Ⅲ. Morsollized bone grafting was used in 24 cases, bulk structural bone grafting in 6 cases and mixed bone grafting in 7 cases. Twenty-one patients used cementless prosthesis and 16 used cemented prosthesis. The average follow-up period was 53.7 months (6.5 to 130.5 months), the average preoperative Harris hip score was 42±8 with contrast to 87±5 of post-operation. Statistically significant difference was found according to t-test with P value less than 0.05. Major or complete healing of grafting bone was obtained at the latest follow-up. Conclusions Acetabular bone defect during primary or revision total hip arthroplasty should be reconstructed according to its characteristics and severity. For relatively simple AAOS type Ⅰ and type Ⅱ cases, morsellized or bulk structural bone grafting together with cementless prosthesis could achieve favorable initial stability, but for

  8. Bone scans after total knee arthroplasty in asymptomatic patients. Cemented versus cementless

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, A.A.; Wyatt, R.W.; Daniels, A.U.; Armstrong, L.; Alazraki, N.; Taylor, A. Jr. (Univ. of Utah Medical Center, Salt Lake City (USA))

    1990-02-01

    The natural history of bone scans after total knee arthroplasty (TKA) was studied in 26 patients with 28 cemented TKAs and 29 patients with 31 cementless TKAs. The bone scans were examined at specified postoperative intervals. Radionuclide activity of the femoral, tibial, and patellar regions was measured. Six patients who developed pain postoperatively were excluded. Bone scans immediately postoperative and at three months demonstrated increased uptake, which gradually decreased to baseline levels at ten to 12 months. Radioisotope uptake was comparable in the cemented and cementless groups, but was highly variable in individual patients and in each of the follow-up periods. A single postoperative bone scan cannot differentiate component loosening from early bone remodeling. Sequential bone scans, as a supplement to the clinical examination and conventional radiography, may prove useful in the diagnosis of TKA failure.

  9. Pre-clinical studies to validate the MITCH PCR Cup: a flexible and anatomically shaped acetabular component with novel bearing characteristics.

    Science.gov (United States)

    Latif, Ahmed M H; Mehats, Aude; Elcocks, Martyn; Rushton, Neil; Field, Richard E; Jones, Eric

    2008-04-01

    A previous clinical study was undertaken to evaluate the safety and efficacy of an anatomically shaped, flexible acetabular cup. Clinical results achieved were satisfactory, although some deficiencies in the model were identified. Design changes to the original model have been implemented to improve both initial stability and long term biological fixation. This was achieved through modifications made to both the anchoring mechanism and by the application of an appropriate backing surface layer promoting bone on-growth. In addition, changes to the articulation couple have also been introduced to improve implant durability and bearing performance, utilising a carbon fibre reinforced polyetheretherketone--alumina couple. Simulated loading, in both models, was performed using Finite Element Analysis. Mechanical and tribological tests were also performed to ensure the robustness of the new optimised design. Bio-compatibility of the articulation couple was demonstrated using an animal model. Implantation of the device has been extensively tested and re-validated in vitro to achieve a favourable polar contact between cup and femoral head and establish a reproducible operative technique. This preliminary work is undertaken prior to commencing a post market surveillance study of the CE marked implant.

  10. 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.

  11. Prospective study of the cementless "New Wave" total knee mobile-bearing arthroplasty: 8-year follow-up.

    Science.gov (United States)

    Normand, Xavier; Pinçon, Jean-Louis; Ragot, Jean-Marie; Verdier, Régis; Aslanian, Thierry

    2015-02-01

    One of the main factors affecting the survival of a total knee arthroplasty (TKA) is the fixation method. The constraints placed on the bone-implant interface of a mobile-bearing TKA must be taken in account during the design and evaluation phases. For more than two decades, calcium phosphate ceramics, particularly hydroxyapatitis, have been used in Europe to accelerate the bone integration of cementless implants. A prospective study of patients continuously recruited by three senior surgeons at three French private hospitals has been carried out. There were no exclusion criteria. Eighty-four (84) cementless mobile-bearing total knee prosthesis of the brand "New Wave" were implanted in 74 patients over a 2-year period (2004-2005). Implant survival at 8 years was 95% [with a confidence interval of 95%: 80.2-96.4%] when revision for any cause was defined as the endpoint. Five implants required surgical revision to exchange all or part of the implant: two for aseptic loosening of tibial component, one for osteolysis, one for persistent flessum (30°) and one for tibial periprosthetic fracture. Completely integrated implants and event-free outcomes were recorded in 91.4% of the cases at eight-year follow-up. The Hospital for Special Surgery score significantly improved from 56.8/100 points before the surgery to 83.9/100 points at the last follow-up (p < 0.05). Radiologically, only one patient had radiolucent lines around the tibial and femoral components. This cementless total knee prosthesis yielded good medium-term survival. Cementless arthroplasty can generate solid and durable bone fixation in this total weight-bearing implant, and it seems that the hidroxyapathitis surface in this series stimulate the bone integration at the bone-implant interface.

  12. Cementless bipolar hemiarthroplasty in femoral neck fractures in elderly

    Directory of Open Access Journals (Sweden)

    SKS Marya

    2011-01-01

    Conclusion: Cementless bipolar hemiarthroplasty for femoral neck fractures in the very elderly permits early return to premorbid life and is not associated with any untoward cardiac event in the perioperative period. It can be considered a treatment option in this select group.

  13. Early follow-up of total hip arthroplasty with Accolade TMZF cementless femoral prosthesis%Accolade TMZF生物型股骨假体用于全髋置换的早期随访

    Institute of Scientific and Technical Information of China (English)

    朱永生; 徐耀增; 朱锋; 吴广鹏; 邵洪国

    2015-01-01

    BACKGROUND:Compared with the fixation of bone cement prosthesis,the fixation of cementless femoral prosthesis does not have the folowing worries,including cement-prosthesis separation,cement sheath rupture,and cement debris-induced osteolysis.Long-term outcomes are good,and the survival rate is high.OBJECTIVE: To observe the preliminary clinical results and complications of total hip arthroplasty with Accolade TMZF cementless femoral stem.METHODS:From February 2010 to July 2012,67 patients (70 hips) underwent primary total hip arthroplasty with cementless femoral stem.Al patients were treated with Accolade TMZF Biological hip prosthesis system.Femoral component was treated with the same Accolade TMZF cementless femoral stem.Acetabular component was treated with Secure-fit HA and Trident PSL HA.The first mortar joint friction surface was treated withceramic-ceramic composite in 49 hips,ceramic-polyethylene composite in 19 hips and metal-polyethylene composite in 2 hips.After replacement,hip imaging data were utilized to assess biological fixation of femoral stem prosthesis,osteolysis surrounding the prosthesis,and prosthesis subsidence,and to observe hip function,thigh pain and complications.RESULTS AND CONCLUSION:Al cases were folowed up for more than 2 years.The mean Harris hip score was (32.7±6.2) preoperatively,and improved to (89.2±5.1) during final folow-up.During final folow-up,four patients (6%) suffered from slight pain.No moderate and severe pain or extremely severe pain occurred.None of the patients needed second operation due to failure for various reasons.X-ray films showed that no prosthesis displacement or loosening.Bone fixation surrounding the prosthesis was visible at the femoral side.Only one hip had subsidence of less than 2 mm,and the remaining did not experience subsidence.No blood vessels or nerve injury appeared during the surgery.During prosthesis placement,femoral calcar cleavage fracture occurred in 4 hips,so wire cerclage was used

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

    NARCIS (Netherlands)

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

    2014-01-01

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

  15. CT classification of acetabular fractures

    Energy Technology Data Exchange (ETDEWEB)

    Marincek, B.; Porcellini, B.; Robotti, G.

    1984-05-01

    The contribution of computed tomography (CT) in classifying acetabular fractures was analysed retrospectively in 33 cases. CT and plain radiography classification agreed in 27 cases (82%). CT revealed more extensive fractures in 6 patients (thereof 5 patients with associated fractures). In 10 patients (thereof 9 patients with associated fractures) CT showed intraarticular fragments; radiographically intraarticular fragments were seen only in 2 patients and suspected in 4. CT is of considerable aid in defining the fracture pattern. It should be used mainly in patients with radiographically difficult interpretable associated fractures in order to assess preoperatively the weight-bearing part of the acetabulum, the degree of displacement and the presence of intraarticular fragments.

  16. Research synthesis of recommended acetabular cup orientations for total hip arthroplasty.

    Science.gov (United States)

    Harrison, Claire L; Thomson, Avril I; Cutts, Steven; Rowe, Philip J; Riches, Philip E

    2014-02-01

    Total hip arthroplasty (THA) is regarded as one of the most successful surgical procedures of modern times yet continues to be associated with a small but significant complication rate. Many early failures may be associated with poor component positioning with, in particular, acetabular component orientation dependent on the subjective judgement of the surgeon. In this paper, we compare the manufacturers' instructions on acetabular cup orientation with the literature-based recommended safety zones and surgical technique, by transforming them onto a single, clinically-relevant framework in which the different reference systems, safety guidelines and current instrumentation surgical techniques can be evaluated. The observed limited consensus between results reflects ongoing uncertainty regarding the optimum acetabular component positioning. As malpositioning of the acetabular cup increases the risk of revision surgery, any ambiguity over the correct position can have a causal effect. Our analysis highlights the need for a surgical reference system which can be used to describe the position of the acetabular cup intra-operatively.

  17. 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.

  18. Midterm results of cementless primary total hip arthroplasty%生物型初次全髋关节置换术的中期随访结果

    Institute of Scientific and Technical Information of China (English)

    何平; 龚翰; 陈东峰; 卢伟杰

    2016-01-01

    test and Chi square test were used.Kaplan-Meier method was used to evaluate the survivorship of prothesis .Results A total of 126 hips in 116 patients were available .The average Harris score improved from preoperative ( 50.3 ±13.2 ) to (96.4 ±5.1) at the last follow-up ( t =3.124, P <0.001 ) .The postoperative complications included aseptic loosening ( seven hips ) , dislocation ( three hips ) , deep vein thrombosis ( one hip ) , and ectopic ossification (11 hips).The survivorship of femoral components was 100% as revision caused by aseptic loosening was set for the endpoint , while that of the acetabular components was 88%.Conclusion Primary total hip arthroplasty with cementless prothesis in this group shows a satisfactory clinical and radiographic outcomes in the midterm follow-up.

  19. Preparation of the Femoral Bone Cavity for Cementless Stems

    DEFF Research Database (Denmark)

    Hjorth, Mette H; Kold, Søren; Søballe, Kjeld;

    2016-01-01

    BACKGROUND: Short-term experimental and animal studies have confirmed superior fixation of cementless implants inserted with compaction compared to broaching of the cancellous bone. METHODS: Forty-four hips in 42 patients (19 men) were randomly operated using cementless hydroxyapatite-coated Bi......-Metric stems. Patients were followed with radiostereometric analysis at baseline, 6 and 12 weeks, 1, 2, and 5 years, and measurements of periprosthetic bone mineral density at baseline, 1, 2, and 5 years. Complications during the study period and clinical outcome measures of Harris Hip Score were recorded...... follow-ups (P > .13). The compaction group had significantly less bone loss than the broaching group in Gruen zone 3 (distal-lateral to the stem) at 1 and 5 years. No further differences in bone mineral density changes were found between groups up to 5 years after surgery. Complications throughout...

  20. 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.

  1. PRIMARY CEMENTLESS TOTAL HIP ARTHROPLASTY IN ANKYLOSING SPONDYLITIS

    Directory of Open Access Journals (Sweden)

    Nageshwara Rao

    2015-12-01

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

  2. Acetabular roof arc angles and anatomic biomechanical superior acetabular weight bearing area

    Directory of Open Access Journals (Sweden)

    Thossart Harnroongroj

    2014-01-01

    Full Text Available Background: Acetabular fracture involves whether superior articular weight bearing area and stability of the hip are assessed by acetabular roof arc angles comprising medial, anterior and posterior. Many previous studies, based on clinical, biomechanics and anatomic superior articular surface of acetabulum showed different degrees of the angles. Anatomic biomechanical superior acetabular weight bearing area (ABSAWBA of the femoral head can be identified as radiographic subchondral bone density at superior acetabular dome. The fracture passes through ABSAWBA creating traumatic hip arthritis. Therefore, acetabular roof arc angles of ABSAWBA were studied in order to find out that the most appropriate degrees of recommended acetabular roof arc angles in the previous studies had no ABSAWBA involvement. Materials and Methods: ABSAWBA of femoral head was identified 68 acetabular fractures and 13 isolated pelvic fractures without unstable pelvic ring injury were enrolled. Acetabular roof arc angle was measured on anteroposterior, obturator and iliac oblique view radiographs of normal contralateral acetabulum using programmatic automation controller digital system and measurement tools. Results: Average medial, anterior and posterior acetabular roof arc angles of the ABSAWBA of 94 normal acetabulum were 39.09 (7.41, 42.49 (8.15 and 55.26 (10.08 degrees, respectively. Conclusions: Less than 39°, 42° and 55° of medial, anterior and posterior acetabular roof arc angles involve ABSAWBA of the femoral head. Application of the study results showed that 45°, 45° and 62° from the previous studies are the most appropriate medial, anterior and posterior acetabular roof arc angles without involvement of the ABSAWBA respectively.

  3. Influence of pelvic obliquity in lateral position to acetabular component orientation during total hip arthroplasty%侧卧位时头尾侧骨盆倾斜对全髋关节置换髋臼杯外展角的影响及校正

    Institute of Scientific and Technical Information of China (English)

    秦彦国; 王金成; 李学州; 刘潼; 肖建林; 韩青; 张远鹰; 高忠礼

    2013-01-01

    目的 探讨侧卧位时骨盆向头尾侧倾斜的程度及其对髋关节置换术中髋臼假体外展角的影响及校正方法.方法 将50例62髋拟行全髋关节置换术的患者随机分为校正组及对照组,均采用侧卧位后外侧入路手术.对照组25例28髋以常规方法放置髋臼假体,校正组25例34髋进行水平仪及铅垂法校正后放置髋臼假体.术后测量两组患者髋臼杯外展角,并比较与术中预估的差异.结果 校正组在侧卧位未校正前骨盆整体倾斜-1.647°±4.512°,向头侧倾斜-(4.989°±2.778°),向尾侧倾斜2.587°±1.927°;头侧倾斜偏离大于尾侧,差异有统计学意义.校正组术后髋臼杯外展角为42.685°±3.355°,术中预估与术后测量偏差1.962°±1.515°;对照组术后髋臼杯外展角为44.534°±4.844°,术中预估与术后测量偏差4.244°±3.042°;校正组偏差小于对照组,差异有统计学意义.结论 侧卧位时头尾侧骨盆倾斜影响术者对髋臼外展角的判断,可能造成髋臼假体放置角度不准确.通过水平仪及铅垂法进行校正可提高判定髋臼假体外展角的准确性.%Objective To explore the influence of pelvis obliquity in lateral position to acetabular component orientation during total hip arthroplasty (THA),and the method to correct.Methods Fifty patients (62 hips) were performed THA with posterolateral incision in lateral position by the same team.The patients were randomized and divided into experimental group (EX,with 25 cases,34 hips) and control group (CON,with 25 cases,28 hips).In EX group,the acetabular components were placed by means of the gradienter and plumb correcting technique during THA.While in CON group,the acetabular components were placed by traditional method during THA.The acetabular abduction angles were measured postoperatively,and compared between the two groups.Results The average obliquity of pelvis was-1.647°±4.512°in EX group when putting the patient in lateral

  4. 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.

  5. Coralline hydroxyapatite in complex acetabular reconstruction.

    Science.gov (United States)

    Wasielewski, Ray C; Sheridan, Kate C; Lubbers, Melissa A

    2008-04-01

    This retrospective study examined whether a coralline hydroxyapatite bone graft substitute adequately repaired bone defects during complex acetabular reconstructions. Seventeen patients who underwent acetabular revision using Pro Osteon 500 were assessed to determine whether any cups required re-revision, whether bone had incorporated into the coralline hydroxyapatite grafts, and whether the coralline hydroxyapatite grafts resorbed with time. At latest follow-up, no cups required re-revision, but 1 had failed. Radiographic evidence of bone incorporation was observed in every coralline hydroxyapatite graft. Graft resorption was not observed.

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

    LENUS (Irish Health Repository)

    Banks, Louisa N

    2012-02-01

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

  7. CT evaluation of acetabular dysplasta in adults.

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

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

  8. 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.

  9. Computed tomography of the acetabular fractures

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ho Young; Suh, Jin Suck; Park, Chang Yun; Lee, Kil Woo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1986-04-15

    In a retrospective study of 21 patients, in whom the acetabular fractures were suspected on initial radiographs, we compared and analysed the computed tomographic findings and plain radiographic findings. The results were as follow: 1. In patients with multiple trauma, no further change in position was required during CT examinations. 2. CT showed intraarticular loose bodies, which were invisible on plain radiographs. 3. CT was useful in detecting the fractures of acetabular rims, medial wall of acetabulum, and femoral head. 4. CT permitted better evaluation of shape, extent, and degree of separation of fracture fragments. 5. CT was helpful in detecting the associated fractures and soft tissue injuries. 6. CT also demonstrated the adequacy of reduction, the position of metallic fixation devices, and the presence or absence of remaining intraarticular osseous fragments after surgery.

  10. ACETABULAR ROTATION OSTEOTOMY IN THE TREATMENT OF ACETABULAR DYSPLASIA IN ADULTS

    Institute of Scientific and Technical Information of China (English)

    杨庆铭; 蒋垚; 孙争鸣; 钱不凡

    1993-01-01

    Acetabular dysplasia is one of the most important reasons for development ofsecondary osteoarthrosis of the hip joint. This paper introduced a method of modifiedWagner’s procedure, called acetabular rotation osteotomy for the treatment of severeacetabular dysplasia in ten adults patients. These were followed up for 1-4 years. Fivecriteria including pain, gait, range of motion, measurement of roentgenographic changees,and CT scan were evaluated. From the limited information of this paper, it showed thatin all cases pain improved and range of motion did not reduced significantly. Comparingthe pre- and post-operative x-ray films, CE angle increased and exceeded the normal val-ue. Tonnis hip value decreased and approached the normal value, anteversion of theacetabulum improved, and the percentage of acetabular coverage increased as well.

  11. Surgical treatment of displaced acetabular fractures

    Directory of Open Access Journals (Sweden)

    Milenković Saša

    2011-01-01

    Full Text Available Introduction. Acetabular fractures are severe injuries, generally caused by high-energy trauma, most frequently from traffic accidents or falls from heights. Fractures of the extremities, head injuries, chest, abdomen and pelvic ring injuries are most commonly associated injuries. Objective. The purpose of this study was to evaluate the results of open reduction and internal fixation of acetabular fractures. The open anatomical reduction of the articular surface combined with a rigid internal fixation and early mobilisation have become the standard treatment of these injuries. Methods. We conducted a retrospective analysis of 22 patients of average age 43.13 years. The patients were treated by open reduction and internal fixation at the Orthopaedic Clinic of Niš from 2005-2009. The follow-up was 12 to 60 months, with the average of 21.18 months after surgery. Results. All injured patients were operated on between 4 and 11 days (5.7 days on the average. According to the classification by Judet and Letournel, 15 (68.18% patients had an elementary acetabular fracture, whereas 7 (31.82% patients had associated fracture. A satisfactory postoperative reduction implying less than 2 mm of displacement was achieved in 19 (86.36% patients. The radiological status of the hip joint, determined according to Matta score, was excellent in 15 (68.18% patients, good in 4 (18.18% patients and moderate in 3 (13.63% patients. According to Merle d’Aubigné Scale, the final functional results of the treatment of all operated patients were excellent in 12 (54.54% patients, good in 7 (31.81% patients and moderate in 3 (13.63% patients. Conclusion. Surgical treatment of dislocated acetabular fractures requires an open reduction and a stable internal fixation. Excellent and good results can be expected only if anatomical reduction and stable internal fixation are achieved.

  12. Plain film analysis of acetabular fracture

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang Soo; Han, Sang Suk; Yoon, Eu Giene; Cha, Seong Sook; Eun, Tchoong Kie; Chung, Duck Hwan [Inje Medical College Paik Hospital, Pusan (Korea, Republic of)

    1986-02-15

    Acetabular fracture can result in severe limitation of the motion of the hip joint, which supports total weight of human body. Because of different methods of surgical approach according to fracture type, precise interpretation of X-ray films of acetabular fracture is required. We reviewed 38 cases of simple X-ray films showing acetabular fracture. The results were as follows: 1. Almost 60% of the cases-were in their 2nd and 3rd decades. 2. Twenty cases were male, and 18 cases were female. 3. The most common cause of the injury was traffic accident (33 cases, 86.8%), followed by fall down (4 cases, 10.5%), and slip down (1 case, 2.7%). 4. Elementary fractures were 21 cases (55.3%), and associated fractures were 17 cases (44.7%). 5. Among elementary fractures, posterior wall fractures were 9 cases (23.7%), followed by anterior column fractures (8 cases, 21.1%), anterior wall fractures (4 cases, 10.5%). 6. Among associated fractures, T-shaped fractures were 8 cases (21.1%), followed by both column fractures (6 cases, 15.8%), anterior and hemitransverse fractures (3 cases, 7.8%). 7. Other pelvic bone fractures associated with the acetabular fracture were as follows: fractures of contralateral pubic rami (6 cases, 15.8%) contralateral iliac bone (1 case, 2.6%) and ipsilateral iliac bone (1 case, 2.6%). 8. Injuries of other organs adjacent to the acetabulum were as follows: rupture of the bladder (3 cases, 7.9%), urethra (2 cases, 5.3%) and uterus (1 cases, 2.6%)

  13. 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.

  14. 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.

  15. 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.

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

    Directory of Open Access Journals (Sweden)

    Cheah Chee Ban

    2014-01-01

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

  17. Conservatively treated acetabular fractures: A retrospective analysis

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    Narender Kumar Magu

    2012-01-01

    Full Text Available Background: There are a few studies reporting the long term outcome of conservatively treated acetabular fractures. The present study aims to evaluate the quality of reduction, and radiological and functional outcome in displaced acetabular fractures treated conservatively. Materials and Methods: Sixty-nine patients (55 men and 14 women with 71 displaced acetabular fractures (mean age 38.6 years managed conservatively were retrospectively evaluated. There were 11 posterior wall, 5 posterior column, 6 anterior column, 13 transverse, 2 posterior column with posterior wall, 9 transverse with posterior wall, 6 T-shaped, 1 anterior column with posterior hemi-transverse, and 18 both-column fractures. The follow-up radiographs were graded according to the criteria developed by Matta J. Functional outcome was assessed using Harris hip score and Merle d′Aubigne and Postel score at final followup. Average follow-up was 4.34 years (range 2-11 years. Results: Patients with congruent reduction (n=45 had good or excellent functional outcome. Radiologic outcome in incongruent reduction (n=26 was good or excellent in 6 and fair or poor in 20 hips. The functional outcome in patients with incongruent reduction was good or excellent in 16 and satisfactory or poor in 10 hips. Good to excellent radiologic and functional outcome was achieved in all patients with posterior wall fractures including four having more than 50% of broken wall. Good to excellent functional outcome was observed in 88.8% of both-column fractures with secondary congruence despite medial subluxation. Conclusions: Nonoperative treatment of acetabular fractures can give good radiological and functional outcome in congruent reduction. Posterior wall fractures with a congruous joint without subluxation on computed tomography axial section, posterior column, anterior column, infratectal transverse or T-shaped, and both-column fractures may be managed conservatively. Small osteochondral fragments

  18. 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.

  19. 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.

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

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    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.

  1. Acetabular paralabral cyst: an uncommon cause of sciatica

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

    2003-02-01

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

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

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    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.

  3. Trabecular metal cup without augments for acetabular revision in case of extensive bone loss and low bone-prosthesis contact.

    Science.gov (United States)

    Pierannunzii, L; Mambretti, A; D'Imporzano, M

    2011-01-01

    Current evidences in revision hip arthroplasty suggest to treat severe acetabular bone loss with dedicated implants, such as anti-protrusio cages, stemmed cups, modular systems supplied with iliac flanges and obturatory hook. However recent literature is reporting satisfactory outcomes with simple elliptical Trabecular Metal cups. Purpose of the study was to evaluate mid-term results of such a surgical procedure. All hip revisions performed from 2008 to 2009 with implantation of a TMT multi-hole acetabular cup without augmentations were retrospectively reviewed. The cases with low-degree acetabular bone loss (stage I and II according to GIR classification), with surgical report poorly describing the bone defect, with inadequate pre- and post-operative x-rays were ruled out. Twenty-five cases were identified, but four were lost to follow-up. The twenty-one patients were 71 year-old on average (from 60 to 82), with stage IV bone loss in 6 cases and stage III bone loss in 15 cases. Mean interval from surgery to evaluation was 20.9 months (from 13 to 30). The evaluation included bone-prosthesis contact estimation, component position, survivorship, complications, final Harris Hip Score, presence of periprosthetic radiolucencies. Host bone-prosthesis contact was estimated to be about 35%. Only three implant were subsequently reoperated (for infection, early migration, recurrent dislocation). The HHS among non-reoperated 18 patients was 81.96 on average (from 63.44 to 95.82). Six cases showed thin radiolucencies in one of the three Charnley zones, while three cases showed radiolucencies in two. None of these images was evolutive, thus they were not considered signs of loosening. The mid-term results of this series confirm the hypothesis that a porous tantalum acetabular cup is an effective option to deal with difficult acetabular revisions. Although no extra-acetabular fixation device is available, the very high surface friction guaranteed by the material and the

  4. 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

  5. Análise epidemiológica das fraturas acetabulares Epidemiological analysis on acetabular fractures

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    Maurício Silveira Maia

    2011-01-01

    Full Text Available O objetivo deste trabalho é realizar um estudo epidemiológico das fraturas acetabulares na cidade de Campinas e entorno, tendo em vista poucos trabalhos publicados a respeito deste assunto. Prontuários cedidos pelo Serviço de Arquivamento Médico (SAM do Hospital das Clínicas da Universidade Estadual de Campinas (Unicamp, dos anos de 2004 a 2008 com diagnósticos de fratura acetabular foram analisados por seis observadores que coletaram idade do paciente, sexo, lado acometido da fratura, mecanismo de lesão, material de síntese utilizado, complicações operatórias, fraturas associadas, tempo de internação pré e pós- operatória, tempo de internação total e número de sessões de fisioterapia pré e pós-cirurgia. Foi observado nesta demografia que o lado esquerdo foi o mais acometido; mecanismo de lesão que mais ocasiona esse tipo de fratura são os acidentes automobilísticos; das complicações cirúrgicas, as lesões do ciático tiveram maior ocorrência; o material de síntese mais utilizado são as placas de reconstrução.This aim of this work was to carry out an epidemiological study on acetabular fractures in the city of Campinas and surrounds, in view of the few published papers on this subject. Medical files with a diagnosis of acetabular fracture between the years 2004 and 2008 that were made available by the Medical Archiving Service of Hospital das Clínicas, State University of Campinas (UNICAMP were analyzed by six observers. Data on patients' ages, sex, side affected by the fracture, mechanism of injury, material used for synthesis, complications of the operation, associated fractures, length of hospitalization before and after the surgery, time of total internment and number of physiotherapy sessions before and after the surgery were gathered. It was observed in this population that the left side was more affected; the mechanism of injury that most often caused this type of fracture was automobile accidents

  6. 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.

  7. Total hip replacement: A meta-analysis to evaluate survival of cemented, cementless and hybrid implants

    Science.gov (United States)

    Phedy, Phedy; Ismail, H Dilogo; Hoo, Charles; Djaja, Yoshi P

    2017-01-01

    AIM To determine whether cemented, cementless, or hybrid implant was superior to the other in terms of survival rate. METHODS Systematic searches across MEDLINE, CINAHL, and Cochrane that compared cemented, cementless and hybrid total hip replacement (THR) were performed. Two independent reviewers evaluated the risk ratios of revision due to any cause, aseptic loosening, infection, and dislocation rate of each implants with a pre-determined form. The risk ratios were pooled separately for clinical trials, cohorts and registers before pooled altogether using fixed-effect model. Meta-regressions were performed to identify the source of heterogeneity. Funnel plots were analyzed. RESULTS Twenty-seven studies comprising 5 clinical trials, 9 cohorts, and 13 registers fulfilled the research criteria and analyzed. Compared to cementless THR, cemented THR have pooled RR of 0.47 (95%CI: 0.45-0.48), 0.9 (0.84-0.95), 1.29 (1.06-1.57) and 0.69 (0.6-0.79) for revision due to any reason, revision due to aseptic loosening, revision due to infection, and dislocation respectively. Compared to hybrid THR, the pooled RRs of cemented THR were 0.82 (0.76-0.89), 2.65 (1.14-6.17), 0.98 (0.7-1.38), and 0.67 (0.57-0.79) respectively. Compared to hybrid THR, cementless THR had RRs of 0.7 (0.65-0.75), 0.85 (0.49-1.5), 1.47 (0.93-2.34) and 1.13 (0.98-1.3). CONCLUSION Despite the limitations in this study, there was some tendency that cemented fixation was still superior than other types of fixation in terms of implant survival.

  8. Acetabular fractures before and after the introduction of seatbelt legislation

    Science.gov (United States)

    Al-Qahtani, Saeed; O’Connor, Gregory

    1996-01-01

    Objectives To compare the incidence and severity of acetabular fractures and associated injuries before and after seatbelt legislation. Design A retrospective study. Setting Two major trauma centres, which are teaching hospitals. Patients Three hundred and ninety-three patients who sustained acetabular fractures during the 5 years before and 5 years after seatbelt legislation was enacted. Of these, the fractures in 198 patients (50.4%) resulted from a motor vehicle accident. Main Outcome Measures The number and severity of acetabular fractures and associated injuries. Results There has been a significant reduction in the number of acetabular fractures (p = 0.005) since seatbelt use became mandatory, and the complexity of the fractures has decreased. There has also been a marked reduction in associated injuries, such as fractures of other bones, and head, chest and abdominal injuries (p < 0.001). Conclusion The seatbelt law has been a useful preventive measure, resulting in a reduction in the incidence of acetabular fractures and associated injuries. PMID:8697323

  9. A Novel Approach for Treatment of Acetabular Fractures

    Science.gov (United States)

    Xue, Zichao; Qin, Hui; Ding, Haoliang; An, Zhiquan

    2016-01-01

    Background There is no single approach that provides adequate exposure for treatment of all types of acetabular fractures. We describe our experience with an easier, relatively less invasive pubic symphysis approach (PSA) for the treatment of acetabular fractures. Material/Methods Between March 2011 and March 2012, fifteen patients with acetabular fracture underwent surgery using the PSA technique. Fracture reduction and treatment outcomes were assessed by clinical and radiological examination. Operation time, intraoperative blood loss and postoperative complications were documented. Results Mean operative time was 222±78 minutes. Average blood loss was 993±361 mL. Anatomical reduction was achieved in all patients. Minimum follow-up period was 31 months. Postoperative hypoesthesia in the area of innervation of the lateral femoral cutaneous nerve was reported in one patient, with spontaneous recovery at one month after surgery. No complications were reported during the follow-up period. At the most recent follow up, clinical outcomes were graded as “excellent” in six patients, “good” in eight patients and “fair” in one patient based on the modified Merle d’Aubigné-Postel score. Conclusions PSA appears to be a timesaving and safe approach for treatment of acetabular fractures that affords good visual access and allows for excellent fracture reduction. Our preliminary results revealed a much lower incidence of complications than traditional approaches, suggesting PSA is an alternative for treatment of acetabular fractures. PMID:27734825

  10. 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.

  11. Surgical Management of Acetabular Fractures: A Case Series

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    Hassan Rahimi

    2013-01-01

    Full Text Available Introduction: For decades, acetabular fractures were treated conservatively. Judet et al. in 1960s established the operative treatment of these fractures by continuous improvement of pre-operative evaluation and classification of fractures. Several studies demonstrated that accurate fracture reduction decreases the incidence of post-traumatic arthritis and improves functional outcome.Case Series: We report 67 consecutive patients who underwent surgical treatment for acetabular fracture; 44 patients were available for follow-up. In 35 (79.5% cases, congruent reductions were achieved. The final mean Harris hip score was 81.8 (53-95. Functional outcomes according to Harris score were excellent and good in 31 patients (70.5%.Conclusions: The results of internal fixation of displaced acetabular fractures in our series were satisfactory.

  12. Total hip arthroplasty using a cementless prosthesis in the treatment of osteoarthritis secondary to developmental dysplasia of the hip%生物型假体全髋关节置换术治疗成人髋关节发育不良继发骨关节炎的疗效评价

    Institute of Scientific and Technical Information of China (English)

    彭昊; 陈森; 郑慧锋; 李建平; 周建林; 方洪松

    2013-01-01

    [目的]评价生物型假体全髋关节置换术(total hip arthroplasty,THA)治疗成人髋关节发育不良(developmental dysplasia of hip,DDH)继发骨关节炎的疗效.[方法]对2002年2月~2009年8月在本院行THA治疗的76例(102髋)髋关节发育不良继发骨关节炎患者的临床及影响学资料进行回顾性分析,其中男34例,女42例;年龄35~64岁,平均52.5岁.用Harris髋关节评分系统评价手术的临床疗效.根据骨盆平片及患髋正、侧位X线片观察髋臼、股骨假体的位置及其周围骨质变化.[结果]所有患者均获2年以上随访,平均5.3年.术后4例仍有轻度疼痛,服用非甾体类止痛药后缓解.8例存在不同程度下肢不等长(0.5 ~1.2 cm),Trendelenburg征阴性,无跛行.末次随访时Harris评分平均值(89.5±3.8)分,优46例(60髋),良20例(30髋),可10例(12髋);优良率为88.2%.末次随访时髋臼假体位置无明显移位,头臼包容性良好.30例出现异位骨化,6例出现髋臼周围骨溶解.股骨柄假体的位置无明显改变,中心固定有98髋(94.1%),柄-髓腔匹配优良率100%.4髋出现股骨侧骨溶解,8髋假体柄与股骨界面出现透亮线.所有病例均出现股骨近端骨重塑,其中Ⅰ度92髋,Ⅱ度10髋.无感染、假体松动、假体周围骨折等并发症发生.[结论]生物型假体全髋关节置换术治疗成人髋关节发育不良继发骨关节炎的疗效满意.%[Objective] To evaluate the effect of total hip arthroplasty using a cementless prosthesis in treating osteoarthritis secondary to developmental dysplasia of the hip in adult.[Methods] Data of 76 patients (102 hips),who had undergone total hip arthroplasty for osteoarthritis secondary to developmental dysplasia of the hip from February 2002 to August 2009,were retrospectively analyzed.There were 34 males and 42 females,aged from 35 to 64 years (average,52.5 years).Harris hip score was used to assess the clinical efficacy.The components migration and

  13. Development of site-specific locking plates for acetabular fractures.

    Science.gov (United States)

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

    2013-05-01

    Site-specific locking plates have gained popularity for the treatment of fractures. However, the clinical use of a site-specific locking plate for acetabular fractures remains untested due to production limits. To design a universal site-specific locking plate for acetabular fractures, the 3-dimensional (3D) photographic records of 171 pelvises were retrospectively studied to generate a universal posterior innominate bone surface. Using 3D photographical processing software, the 3D coordinate system was reset according to bony landmarks and was scaled based on the acetabular diameter to allow a direct comparison between surfaces. The measured surface was separated into measurement units. At each measurement unit, the authors calculated the average z-axis values in all samples and obtained the 3D coordinate values of the point cloud that could be reconstructed into the universal surface. A plate was subsequently designed in 3D photographical processing software, and the orientation and distribution of locking screws was included. To manufacture a plate, the data were entered into Unigraphics NX version 6.0 software (Siemens PLM Software, Co, Ltd, Plano, Texas) and a CNC digital milling machine (FANUC Co, Ltd, Yamanashi, Japan). The resulting locking plate fit excellently with the reduced bone surface intraoperatively. Plate contouring was avoided intraoperatively. Universal 3.5-mm locking screws locked successfully into the plate, and their orientations were consistent with the design. No screw yielded to acetabular penetration. This method of designing a site-specific acetabular locking plate is practical, and the plates are suitable for clinical use. These site-specific locking plates may be an option for the treatment of acetabular fractures, particularly in elderly patients.

  14. 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.)

  15. 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.

  16. Ipsilateral Acetabular and Femoral Neck and Shaft Fractures

    Directory of Open Access Journals (Sweden)

    Hideto Irifune

    2015-01-01

    Full Text Available Floating hip injuries and ipsilateral femoral neck and shaft fractures are rare. Additionally, the simultaneous occurrence of these injuries is extremely rare, and only one case report of the simultaneous occurrence of these injuries has been published. Here, we report the case of a patient with ipsilateral acetabular and femoral neck and shaft fractures following a suicide attempt. The patient experienced nonunion of the femoral neck and shaft after the initial operation and therefore underwent reconstruction using a femoral head prosthesis with a long stem and interlocking screws. Our procedure may be used in primary and/or secondary reconstruction for ipsilateral acetabular and femoral neck and shaft fractures.

  17. Percutaneous acetabuloplasty for metastatic acetabular lesions

    Directory of Open Access Journals (Sweden)

    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.

  18. CHOICE OF SURGICAL APPROACH FOR ACETABULAR COMPONENT’S IMPLANTATION USING CURRENT CLASSIFICATION FOR ARTHRITIS FOLLOWING ACETABULAR FRACTURE

    Directory of Open Access Journals (Sweden)

    R. M. Tikhilov

    2011-01-01

    Full Text Available Degenerative-dystrophic changes in hip after treatment of acetabular fracture, over the time, develops about in 60% of affected people. In such cases, total hip replacement is used. Existing classifications (for example AO or Letournel are good for fracture treatment, but not for arthritis following acetabular fracture. The group of patients, with post traumatic arthritis, is heterogeneous with severity of post traumatic anatomic changes. Basis for surgical approach, could be current classification for post traumatic changes – taking into account features of anatomic functional changes in hip and the bone defects of acetabulum. In this article is demonstrated X-ray and clinical basing for current classification.

  19. Comparison of Biocompatibility of Cemented vs. Cementless Hip Joint Endoprostheses Based on Postoperative Evaluation of Proinflammatory Cytokine Levels

    Science.gov (United States)

    Szypuła, Jan; Cabak, Anna; Kiljański, Marek; Boguszewski, Dariusz; Tomaszewski, Wiesław

    2016-01-01

    Background The yearly increase in the number of procedures involving implantation of hip joint endoprostheses forces prosthetics manufacturers to search for biologically neutral implants. The goal of this study was to assess the concentration of Interleukin-6 (IL-6) and its correlation with C-reactive protein (CRP), depending on the type of hip joint endoprosthesis (cemented or cementless endoprosthesis) in order to determine implant biotolerance during the early postoperative period. Material/Methods The sample comprised 200 patients [mean age=64 (31–81) years] with coxarthrosis. All patients underwent hip joint arthroplasty using a cemented or cementless endoprosthesis. Blood samples were collected 3 times: before the procedure, on the first day after the procedure, and after 6 weeks. IL-6 and CRP levels were assayed using immunoenzymatic methods. The results were subjected to statistical analysis using the Shapiro-Wilk test. Results On the 1st day after the procedure, CRP and IL-6 concentration increased rapidly after implantation of both cemented and cementless endoprostheses. At 6 weeks postoperatively, the CRP value remained at a similar level in patients after cemented arthroplasty and was almost 2-fold lower in patients who underwent cementless arthroplasty. The IL-6 value returned to the baseline level in patients after cementless arthroplasty and showed an ongoing increasing tendency in patients after cemented arthroplasty. Conclusions 1. The measurement of C-reactive protein and Interleukin-6 is a high-sensitivity test, assessing implant biotolerance. 2. The implantation of a cemented endoprosthesis induces a higher increase in the level of proinflammatory cytokines as compared with a cementless endoprosthesis. 3. For a complete assessment of both early and later body responses to implantation and the related surgical procedure, further studies using available approaches and tools are recommended. PMID:27935873

  20. Comparison of Acetabular Bone Resection, Offset, Leg Length and Post Operative Function Between Hip Resurfacing Arthroplasty and Total Hip Arthroplasty.

    Science.gov (United States)

    Parry, Michael C; Povey, James; Blom, Ashley W; Whitehouse, Michael R

    2015-10-01

    Controversy exists regarding the amount of acetabular bone resection, biomechanics and function of patients receiving either total hip arthroplasty (THA) or hip resurfacing arthroplasty (HRA). A cohort of patients undergoing 36 mm ceramic-on-ceramic THA (89) or metal-on-metal HRA (86) were compared. No difference was observed when the ratio of native femoral head size was compared to the implanted acetabular component size (1.15 ± 0.1 HRA c.f. 1.13 ± 0.1 THA). No difference was observed in acetabular offset, vertical centre of rotation or function (OHS mean 47 in both groups) but leg length discrepancy (1.8 mm c.f. 5.5 mm) and femoral offset did differ (0.6 mm c.f. 4.1 mm). This demonstrates that 36 mm ceramic-on-ceramic THA is not associated with more bone resection than HRA and achieves equivalent function whilst avoiding the problems of metal-on-metal bearings.

  1. Central acetabular fracture dislocations: an unusual complication of seizures

    Energy Technology Data Exchange (ETDEWEB)

    Lovelock, J.E.; Monaco, L.P.

    1983-08-01

    Central acetabular fracture-dislocations resulting from convulsions are rare. The literature is reviewed in this regard and we add two additional cases in which hyponatremia was the cause of seizure activity. In most cases this type of injury is seen in bone already weakened by underlying disease.

  2. Impaction bone grafting and a cemented cup after acetabular fracture

    NARCIS (Netherlands)

    Bronsema, E.; Stroet, M.A. Te; Zengerink, M.; Kampen, A. van; Schreurs, B.W.

    2014-01-01

    PURPOSE: Patients suffering from post traumatic osteoarthritis of the acetabulum often require a total hip arthroplasty at a relatively young age. Long-term data outcome studies for this population are lacking. We report on the long-term outcome of 20 acetabular fractures in 20 patients treated with

  3. 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.

  4. 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.)

  5. 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.)

  6. 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

  7. 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

  8. 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) agr...

  9. Intra-operative evaluation of cementless hip implant stability: a prototype device based on vibration analysis.

    Science.gov (United States)

    Lannocca, Maurizio; Varini, Elena; Cappello, Angelo; Cristofolini, Luca; Bialoblocka, Ewa

    2007-10-01

    Cementless implants are mechanically stabilized during surgery by a press-fitting procedure. Good initial stability is crucial to avoid stem loosening and bone cracking, therefore, the surgeon must achieve optimal press-fitting. A possible approach to solve this problem and assist the surgeon in achieving the optimal compromise, involves the use of vibration analysis. The present study aimed to design and test a prototype device able to evaluate the primary mechanical stability of a cementless prosthesis, based on vibration analysis. In particular, the goal was to discriminate between stable and quasi-stable implants; thus the stem-bone system was assumed to be linear in both cases. For that reason, it was decided to study the frequency responses of the system, instead of the harmonic distortion. The prototype developed consists of a piezoelectric exciter connected to the stem and an accelerometer attached to the femur. Preliminary tests were performed on four composite femurs implanted with a conventional stem. The results showed that the input signal was repeatable and the output could be recorded accurately. The most sensitive parameter to stability was the shift in resonance frequency of the stem-bone system, which was highly correlated with residual micromotion on all four specimens.

  10. 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.

  11. 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.)

  12. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kuhlman, J.E.; Fishman, E.K.; Ney, D.R.; Brooker, A.F. Jr.; Magid, D.

    1989-01-01

    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.

  14. 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.

  15. 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.).

  16. Pelvic muscle and acetabular contact forces during gait.

    Science.gov (United States)

    Pedersen, D R; Brand, R A; Davy, D T

    1997-09-01

    Locations, magnitudes, and directions of pelvic muscle and acetabular contact forces are important to model the effects of abnormal conditions (e.g., deformity, surgery) of the hip accurately. Such data have not been reported previously. We computed the three-dimensional locations of all pelvic muscle and acetabular contact forces during level gait. The approach first required computation of the intersegmental joint resultant forces and moments using limb displacement history, foot-floor forces, and estimated limb inertial properties from one subject. The intersegmental resultant moments were then distributed to the muscles using a 47-element muscle model and a non-linear optimization scheme. Muscle forces were vectorally subtracted from the intersegmental resultants to compute the acetabular contact forces. While the peak joint force magnitudes are similar to those reported previously for the femur, the directions of pelvic contact forces and muscle forces varied considerably over the gait cycle. These variations in contact force directions and three-dimensional forces could be as important as the contact force magnitudes in performing experimental or theoretical studies of loads and stresses in the periacetabular region.

  17. Component

    Directory of Open Access Journals (Sweden)

    Tibor Tot

    2011-01-01

    Full Text Available A unique case of metaplastic breast carcinoma with an epithelial component showing tumoral necrosis and neuroectodermal stromal component is described. The tumor grew rapidly and measured 9 cm at the time of diagnosis. No lymph node metastases were present. The disease progressed rapidly and the patient died two years after the diagnosis from a hemorrhage caused by brain metastases. The morphology and phenotype of the tumor are described in detail and the differential diagnostic options are discussed.

  18. 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.

  19. 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...

  20. 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

  1. 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.

  2. Sacroiliac joint dysfunction as a reason for the development of acetabular retroversion: a new theory.

    Science.gov (United States)

    Cibulka, Michael T

    2014-05-01

    Acetabular retroversion has been recently implicated as an important factor in the development of femoral acetabular impingement and hip osteoarthritis. The proper function of the hip joint requires that the anatomic features of the acetabulum and femoral head complement one another. In acetabular retroversion, the alignment of the acetabulum is altered where it opens in a posterolaterally instead of anterior direction. Changes in acetabular orientation can occur with alterations in pelvic tilt (anterior/posterior), and pelvic rotation (left/right). An overlooked problem that alters pelvic tilt and rotation, often seen by physical therapists, is sacroiliac joint dysfunction. A unique feature that develops in patients with sacroiliac joint dysfunction (SIJD) is asymmetry between the left and right innominate bones that can alter pelvic tilt and rotation. This article puts forth a theory suggesting that acetabular retroversion may be produced by sacroiliac joint dysfunction.

  3. Improved design of cementless hip stems using two-dimensional functionally graded materials.

    Science.gov (United States)

    Hedia, H S; Shabara, M A N; El-Midany, T T; Fouda, N

    2006-10-01

    Increasingly, it is acknowledged that bone resorption around cementless hip implants may cause future problems. The solution is frequently sought in reducing implant stiffness. However, this confronts the designer with a true design conflict: how to reduce the stiffness without excessively loading the proximal bone/prosthesis interface? The aim of this work is to improve the design of cementless hip stem material, using two-dimensional (2D) functionally graded material (FGM) concept in order to solve the above problems. Two models were used in this analysis, using three materials with different elastic moduli, E(1), E(2), and E(3). In model I, the elastic moduli E(1) and E(2) gradually change along the upper stem surface, while E(3) is maintained constant along all the lower surface of the stem. However, in model II, the elastic moduli E(1) and E(2) gradually change along the lower stem surface, while E(3) is maintained constant all along the upper stem surface. It is found that the recommended model is model I, which has three distinct materials of hydroxyapatite, Bioglass, and collagen. The recommended design of 2D FGM is expected to reduce the stress shielding by 91% and 12%, respectively, compared with titanium stem and model II of FGM. It is found that this new design reduces the maximum interface shear stress at the lateral and medial sides of the femur by about 50%, compared with titanium stem. Furthermore, the maximum interface shear stress is reduced by about 17% and 11% at the lateral and medial sides of the femur, respectively, compared with that of model II of FGM.

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

    Directory of Open Access Journals (Sweden)

    D Neut

    2015-01-01

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

  5. Acoustic pattern evaluation during cementless hip arthroplasty surgery may be a new method for predicting complications

    Science.gov (United States)

    Morohashi, Itaru; Iwase, Hideaki; Kanda, Akio; Sato, Taichi; Homma, Yasuhiro; Mogami, Atsuhiko; Obayashi, Osamu; Kaneko, Kazuo

    2017-01-01

    Background: Although surgeons must perform implantation of the cementless stem during total hip arthroplasty (THA) without complications, assessment is left to the surgeon’s intuitive judgement, which could contain inter/intra-observer bias variety. We therefore asked (1) whether the sound created during the stem implantation could be evaluated objectively and (2) whether those sounds are correlate to the complication specific to the cementless stems. Our hypothesis is that the sounds produced during stem insertion could be quantified and related to the complications. Patients and method: In 71 THAs, we quantified the sound produced during stem insertion and investigated the relationship between these sounds and the occurrence of intraoperative fracture and subsidence. Results: The sound data were divided into two patterns: Patterns A and B. The difference between the peak value (dB) at the most common frequency (near 7 kHz) and the second most common frequency (near 4 kHz) of strikes during the final phase of implantation in Patterns A and B showed a significant difference. Adverse events on intraoperative fracture and subsidence were significantly less common in patients with Pattern A than in those with Pattern B (six of 42 hips with Pattern A and 13 of 29 hips with Pattern B, p = 0.004). Pattern A in predicting a clinical course without those adverse events was 69.2% and the specificity was 68.4%. Positive and negative predictive values were 85.7% and 44.8%, respectively. Conclusion: The sound generated during stem insertion was quantified. Those sound patterns were associated with complications. PMID:28186872

  6. Biomechanical investigation of ambulatory training in patients with acetabular dysplasia.

    Science.gov (United States)

    Kanai, Akira; Kiyama, Takahiro; Genda, Eiichi; Suzuki, Yasuo

    2008-07-01

    The purpose of this study was to investigate the effectiveness and safety of ambulatory training in patients with acetabular dysplasia. To achieve this, we studied the hip joint moment in subjects walking with laterally and horizontally elevated arms and changing speeds as a form of training to strengthen hip joint abductor muscles. We studied eight women with pre- or early stage hip disease (center-edge angle of Wieberg 18.5 degrees to -3.0 degrees ) and six healthy women. In exercise task 1 the subjects walked at a rate of 90 steps/min, with abduction of 90 degrees in the shoulder joint ipsilateral or contralateral to the affected hip joint, and either no load or a 1 kg weight in either hand. In exercise task 2, walking speed was changed in three stages from 60 steps/min (s-gait), 90 steps/min (n-gait), and 120 steps/min (f-gait), with both hands swinging freely. Using results from a three-dimensional motion analysis system, the hip joint moments were calculated. In both the healthy and the acetabular dysplasia groups, the abduction moment of the hip joint decreased significantly with ipsilateral elevation and increased significantly with contralateral elevation. There was no significant change in hip flexion moment in either group. The hip extension moment decreased significantly with contralateral elevation, but no significant changes were seen in ipsilateral elevation. In the walking rate variation, the extension hip moment in fast gait was higher than in slow gait. It was concluded that ambulatory training with contralateral horizontal arm elevation may be an effective way of increasing hip joint abductor muscle strength. Ipsilateral arm elevation decreases gluteus medius muscle tension and is an effective way of ambulatory training for people with compensated trendelenburg gait. Variable speed walking is an effective exercise method that can strengthen extensor muscles. Therefore, these ambulatory training methods are useful for acetabular dysplasia patients.

  7. [Application of three-dimensional printing personalized acetabular wing-plate in treatment of complex acetabular fractures via lateral-rectus approach].

    Science.gov (United States)

    Mai, J G; Gu, C; Lin, X Z; Li, T; Huang, W Q; Wang, H; Tan, X Y; Lin, H; Wang, Y M; Yang, Y Q; Jin, D D; Fan, S C

    2017-03-01

    Objective: To investigate reduction and fixation of complex acetabular fractures using three-dimensional (3D) printing technique and personalized acetabular wing-plate via lateral-rectus approach. Methods: From March to July 2016, 8 patients with complex acetabular fractures were surgically managed through 3D printing personalized acetabular wing-plate via lateral-rectus approach at Department of Orthopedics, the Third Affiliated Hospital of Southern Medical University. There were 4 male patients and 4 female patients, with an average age of 57 years (ranging from 31 to 76 years). According to Letournel-Judet classification, there were 2 anterior+ posterior hemitransverse fractures and 6 both-column fractures, without posterior wall fracture or contralateral pelvic fracture. The CT data files of acetabular fracture were imported into the computer and 3D printing technique was used to print the fractures models after reduction by digital orthopedic technique. The acetabular wing-plate was designed and printed with titanium. All fractures were treated via the lateral-rectus approach in a horizontal position after general anesthesia. The anterior column and the quadrilateral surface fractures were fixed by 3D printing personalized acetabular wing-plate, and the posterior column fractures were reduction and fixed by antegrade lag screws under direct vision. Results: All the 8 cases underwent the operation successfully. Postoperative X-ray and CT examination showed excellent or good reduction of anterior and posterior column, without any operation complications. Only 1 case with 75 years old was found screw loosening in the pubic bone with osteoporosis after 1 month's follow-up, who didn't accept any treatment because the patient didn't feel discomfort. According to the Matta radiological evaluation, the reduction of the acetabular fracture was rated as excellent in 3 cases, good in 4 cases and fair in 1 case. All patients were followed up for 3 to 6 months and all

  8. Acetabular fractures: what radiologists should know and how 3D CT can aid classification.

    Science.gov (United States)

    Scheinfeld, Meir H; Dym, Akiva A; Spektor, Michael; Avery, Laura L; Dym, R Joshua; Amanatullah, Derek F

    2015-01-01

    Correct recognition, description, and classification of acetabular fractures is essential for efficient patient triage and treatment. Acetabular fractures may result from high-energy trauma or low-energy trauma in the elderly. The most widely used acetabular fracture classification system among radiologists and orthopedic surgeons is the system of Judet and Letournel, which includes five elementary (or elemental) and five associated fractures. The elementary fractures are anterior wall, posterior wall, anterior column, posterior column, and transverse. The associated fractures are all combinations or partial combinations of the elementary fractures and include transverse with posterior wall, T-shaped, associated both column, anterior column or wall with posterior hemitransverse, and posterior column with posterior wall. The most unique fracture is the associated both column fracture, which completely dissociates the acetabular articular surface from the sciatic buttress. Accurate categorization of acetabular fractures is challenging because of the complex three-dimensional (3D) anatomy of the pelvis, the rarity of certain acetabular fracture variants, and confusing nomenclature. Comparing a 3D image of the fractured acetabulum with a standard diagram containing the 10 Judet and Letournel categories of acetabular fracture and using a flowchart algorithm are effective ways of arriving at the correct fracture classification. Online supplemental material is available for this article.

  9. 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.

  10. Acetabular orientation variability and symmetry based on CT scans of adults

    Energy Technology Data Exchange (ETDEWEB)

    Lubovsky, Omri; Liebergall, Meir; Khoury, Amal [Hadassah-Hebrew University Medical Center, Orthopedic Surgery Complex, Jerusalem (Israel); Peleg, Eran [Hadassah-Hebrew University Medical Center, Department of Medical Engineering, Jerusalem (Israel); Joskowicz, Leo [Hebrew University of Jerusalem, School of Engineering and Computer Science, Jerusalem (Israel)

    2010-09-15

    Understanding acetabular orientation is important in many orthopaedic procedures. Acetabular orientation, usually described by anteversion and abduction angles, has uncertain measurement variability in adult patients. The goals of this study are threefold: (1) to describe a new method for computing patient-specific abduction/anteversion angles from a single CT study based on the identification of anatomical landmarks and acetabular rim points; (2) to quantify the inaccuracies associated with landmark selection in computing the acetabular angles; and (3) to quantify the variability and symmetry of acetabular orientation. A total of 25 CT studies from adult patients scanned for non-orthopaedic indications were retrospectively reviewed. The patients were randomly selected from the hospital's database. Inclusion criteria were adults 20-65 years of age. Acetabular landmark coordinates were identified by expert observers and tabulated in a spreadsheet. Two sets of calculations were done using the data: (1) computation of the abduction and anteversion for each patient, and (2) evaluation of the variability of measurements in the same individual by the same surgeon. The results were tabulated and summary statistics computed. This retrospective study showed that acetabular abduction and anteversion angles averaged 54 and 17 , respectively, in adults. A clinically significant intra-patient variability of >20 was found. We also found that the right and left side rim plane orientation were significantly correlated, but were not always symmetric. A new method of computing patient-specific abduction and anteversion angles from a CT study of the anterior pelvic plane and the left and right acetabular rim planes was reliable and accurate. We found that the acetabular rim plane can be reliably and accurately computed from identified points on the rim. The novelty of this work is that angular measurements are performed between planes on a 3-D model rather than lines on 2-D

  11. 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.

  12. Function after pelvic tumour resection involving the acetabular ring.

    Science.gov (United States)

    Nilsonne, U; Kreicbergs, A; Olsson, E; Stark, A

    1982-01-01

    Seven patients subjected to pelvic tumour resection involving the acetabular ring were analyzed with respect to function. In addition to conventional clinical assessment gait was analyzed objectively by means of an electronic walk-way and residual hip-muscle power tested by means of a Cybex II dynamometer. Functional results reported by the patients with respect to pain, walking and working capacity appeared better than those elicited by clinical examination. All patients exhibited a marked pelvic tilt and a positive Trendelenburg sign. Only one patient walked without any kind of support. Leg-length discrepancy was on an average 6 cm. Objective gait analysis disclosed that all patients had reduced weight-bearing time on the operated side as compared to the non-operated. This, however, was clearly less pronounced for those patients who appeared best with respect to pain, walking and working capacity. These patients also showed the best hip extension power which appeared more important from a functional point of view than hip flexion and, surprisingly, hip abduction power. Radiographic examination showed that bony support for the proximal femur, provided either by the formation of a bone shelf from the remaining iliac bone or by the remaining iliac bone itself, was of decisive importance for function. The results of the present study show that pelvic tumour resection involving the acetabular ring, provided radical tumour removal can be achieved, constitutes a feasible alternative to hemipelvectomy from a functional point of view.

  13. Atypical periprosthetic acetabular fracture in long-term alendronate therapy

    Science.gov (United States)

    Marongiu, Giuseppe; Capone, Antonio

    2016-01-01

    Summary Bisphosphonates have been commonly used in the treatment of osteoporosis, demonstrating its efficacy in fracture risk reduction. However, even if are generally safe and well tolerated, concerns have emerged about atypical fractures related to its prolonged use. Although atypical femoral fracture are more common, case reports demonstrated that even other skeletal areas can be involved by unusual pattern of fracture. We report a atypical acetabular periprosthetic fracture in a 83-year-old female patient after prolonged alendronate treatment for osteoporosis and isolated acetabular revision surgery. The patient underwent to clinical, bioumoral and radiological evaluation and all the history cases were fully reported. We believe this periprosthetic fracture, according to the available data, may have similar underlying pathology to atypical femoral fractures. Awareness of symptoms, in addition to a regular radiographic survey may facilitate early diagnosis and possible prevention of spontaneous periprosthetic fractures, in patients receiving bisphosphonate therapy beyond 5 years. The treatment of this atypical periprosthetic fracture should include both surgical than pharmacological therapy to obtained bone healing. PMID:28228784

  14. 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.

  15. Autologous Membrane Induced Chondrogenesis (AMIC) for the treatment of acetabular chondral defect

    Science.gov (United States)

    Fontana, Andrea

    2016-01-01

    Summary Background Acetabular chondral defect are very frequently associated to FAI. Treatment options are still questionable. Methods Between 2008 and 2014, 201 patients over 583 have been arthroscopically treated with the AMIC procedure for grade III and/or IV acetabular chondral lesions. Patients age was between 18 and 50 years; acetabular chondral lesion size was between 2 and 4 cm2; radiological Tönnis degree of osteoarthritis was ≤ 2. Results The mean follow up of the entire group of 201 patients was 5 years (from 8 to 2). Significant improvement, as measured by the mHHS, was observed at 6 months in comparison to preoperative levels (80.3 ± 8.3) (prepair medium-sized chondral defects on the acetabular side of the hip found during treatment of FAI and lead to long-term favourable outcomes. Level of evidence IV. PMID:28066742

  16. Acetabular cup position and risk of dislocation in primary total hip arthroplasty

    DEFF Research Database (Denmark)

    Seagrave, Kurt G; Troelsen, Anders; Malchau, Henrik;

    2016-01-01

    Background and purpose - Hip dislocation is one of the most common complications following total hip arthroplasty (THA). Several factors that affect dislocation have been identified, including acetabular cup positioning. Optimal values for cup inclination and anteversion are debatable. We perform...

  17. 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...

  18. 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.

  19. Metallosis with pseudotumour formation: Long-term complication following cementless total hip replacement in a dog

    Science.gov (United States)

    Volstad, Nicola J.; Schaefer, Susan L.; Snyder, Laura A.; Meinen, Jeffrey B.; Sample, Susannah J.

    2017-01-01

    Summary Case description A 10-year-old female Belgian Teruven dog was presented to our clinic for total hip revision following a diagnosis of implant (cup) failure with metallosis and abdominal pseudotumour formation. The patient had a cementless metal-on-polyethylene total hip replacement performed nine years prior to presentation. Clinical findings The clinical findings, including pseudotumour formation locally and at sites distant from the implant and pain associated with the joint replacement, were similar to those described in human patients with this condition. Histopathological, surgical, and radiographic findings additionally supported the diagnosis of metallosis and pseudotumour formation. Treatment and outcome Distant site pseudo tumours were surgically removed and the total hip replacement was explanted due to poor bone quality. The patient recovered uneventfully and has since resumed normal activity. Conclusion In veterinary patients with metal-on-polyethylene total hip implants, cup failure leading to metallosis and pseudotumour formation should be considered as a potential cause of ipsilateral hindlimb lameness, intra-pelvic abdominal tumours, or a combination of both. These clinical findings may occur years after total hip replacement surgery. PMID:27189390

  20. 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

  1. Fabrication of low-cost, cementless femoral stem 316L stainless steel using investment casting technique.

    Science.gov (United States)

    Baharuddin, Mohd Yusof; Salleh, Sh-Hussain; Suhasril, Andril Arafat; Zulkifly, Ahmad Hafiz; Lee, Muhammad Hisyam; Omar, Mohd Afian; Abd Kader, Ab Saman; Mohd Noor, Alias; A Harris, Arief Ruhullah; Abdul Majid, Norazman

    2014-07-01

    Total hip arthroplasty is a flourishing orthopedic surgery, generating billions of dollars of revenue. The cost associated with the fabrication of implants has been increasing year by year, and this phenomenon has burdened the patient with extra charges. Consequently, this study will focus on designing an accurate implant via implementing the reverse engineering of three-dimensional morphological study based on a particular population. By using finite element analysis, this study will assist to predict the outcome and could become a useful tool for preclinical testing of newly designed implants. A prototype is then fabricated using 316L stainless steel by applying investment casting techniques that reduce manufacturing cost without jeopardizing implant quality. The finite element analysis showed that the maximum von Mises stress was 66.88 MPa proximally with a safety factor of 2.39 against endosteal fracture, and micromotion was 4.73 μm, which promotes osseointegration. This method offers a fabrication process of cementless femoral stems with lower cost, subsequently helping patients, particularly those from nondeveloped countries.

  2. 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.)

  3. Value of 3-D CT in classifying acetabular fractures during orthopedic residency training.

    Science.gov (United States)

    Garrett, Jeffrey; Halvorson, Jason; Carroll, Eben; Webb, Lawrence X

    2012-05-01

    The complex anatomy of the pelvis and acetabulum have historically made classification and interpretation of acetabular fractures difficult for orthopedic trainees. The addition of 3-dimensional (3-D) computed tomography (CT) scan has gained popularity in preoperative planning, identification, and education of acetabular fractures given their complexity. Therefore, the authors examined the value of 3-D CT compared with conventional radiography in classifying acetabular fractures at different levels of orthopedic training. Their hypothesis was that 3-D CT would improve correct identification of acetabular fractures compared with conventional radiography.The classic Letournel fracture pattern classification system was presented in quiz format to 57 orthopedic residents and 20 fellowship-trained orthopedic traumatologists. A case consisted of (1) plain radiographs and 2-dimensional axial CT scans or (2) 3-D CT scans. All levels of training showed significant improvement in classifying acetabular fractures with 3-D vs 2-D CT, with the greatest benefit from 3-D CT found in junior residents (postgraduate years 1-3).Three-dimensional CT scans can be an effective educational tool for understanding the complex spatial anatomy of the pelvis, learning acetabular fracture patterns, and correctly applying a widely accepted fracture classification system.

  4. 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.)

  5. 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.

  6. Influences of head/neck ratio and femoral antetorsion on the safe-zone of operative acetabular orientations in total hip arthroplasty

    Institute of Scientific and Technical Information of China (English)

    LI Yong-jiang; YANG Guo-jing; ZHANG Li-cheng; CAI Chun-yuan; WU Li-jun

    2010-01-01

    Objective: To study the influences of head/neck ratio and femoral antetorsion on the safe-zone of operative acetabular orientations, which meets the criteria for desired range of motion (ROM) for activities of daily living in total hip arthroplasty (THA).Methods: Athree-dimensional generic, parametric and kinematic simulation module of THA was developed to analyze the cup safe-zone and the optimum combination of cup and neck antetorsion. A ROM of flexion≥ 120°, internal rotation ≥45° at 90° flexion, extension ≥30° and external rotation ≥ 40° was defined as the criteria for desired ROM for activities of daily living. The cup safe-zone was defined as the area that fulfills all the criteria of desired ROM before the neck impinged on the liner of the cup. For a fixed stemneck (CCD)-angle of 130°, theoretical safe-zones fulfilling the desired ROM were investigated at different general headneck ratios (GR=2, 2.17, 2.37, 2.61 and 2.92) and femoral anteversions (FA=0°, 10°, 20° and 30°).Results: Large GRs greatly increased the size of safezones and when the CCD-angle was 130°, a GR>2.37 could further increase the size of safe-zones. There was a complex interplay between the orientation angles of the femoral and acetabular components. When the CCD-angle was 130°, the optimum relationship between operative acetabular anteversion (OA) and femoral antetorsion (FA) could be estimated by the formula: OA=-0.80×FA+47.06, andthe minimum allowable operative acetabular inclination (OImin) would be more than 210.5×GR-2.255.Conclusions: Large GRs greatly increase the size of safe-zones and it is recommended that the GR be more than 2.37 so as to extend the acceptable range of error that surgeons cannot avoid completely during operation. As to the optimum operative acetabular inclination (OI), surgeons need to make a decision combining with other factors, including stress distribution, soft tissue and cup wear conditions, as well as patients' individual situations

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

    Science.gov (United States)

    Jäger, Marcus; van Wasen, Andrea; Warwas, Sebastian; Landgraeber, Stefan; Haversath, Marcel; Group, Vitas

    2014-04-22

    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 of the implant

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-12-15

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

  14. 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.

  15. 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.

  16. Shape variability of the adult human acetabulum and acetabular fossa related to sex and age by geometric morphometrics. Implications for adult age estimation.

    Science.gov (United States)

    San-Millán, Marta; Rissech, Carme; Turbón, Daniel

    2017-03-01

    This study aims to explore shape variability of the acetabulum during the human adult life span, in relation to sex and age. The human acetabular shape was analysed in 682 os coxae from three different documented skeletal collections from the Iberian Peninsula. Two landmarks and thirty-two sliding semi-landmarks were used for the geometric morphometric procedures and a clock-wise standard was used for orientation. The 180° meridian (6:00) line was positioned over the midpoint of the acetabular notch and 36 reference points in 10° increments along the rim were marked. Data showed that size, sex and age significantly influence acetabular shape variation. Sex differences were significant in individuals younger than 65 years old and were characterised by males exhibiting relatively extended acetabular rim profiles from 10:00 to 1:00, narrower acetabular notches, and reduced acetabular fossae. In addition, three main age-related changes occurred to the acetabular shape in both sexes: outer acetabular profile modification, with extension from 10:00 to 1:00 and reduction from 7:00 to 9:00, acetabular notch narrowing, and acetabular fossa reduction. The age-related changes that were observed are shared by both sexes and seem to be related to bone production associated with age. Specifically, age appears to affect the entire border of the lunate surface: the acetabular rim, both acetabular horns, and the outer edge of the acetabular fossa. Furthermore, shape data confirmed the clover-leaf shape of the acetabular fossa in both males and females. These results improve our understanding of acetabular shape, and assist in refining age-estimation methods and enhancing hip surgery and rehabilitation.

  17. 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.

  18. 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.

  19. 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.)

  20. 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.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Chun, K.A. [The Catholic University of Korea Uijongbu St. Mary' s Hospital, Department of Radiology, Uijongbu, Kyunggi-Do 480-130 (Korea); University of Iowa Hospitals and Clinics, Department of Radiology, Iowa City (United States); Morcuende, J. [University of Iowa Hospitals and Clinics, Department of Orthopaedic Surgery, Iowa City (United States); El-Khoury, G.Y. [University of Iowa Hospitals and Clinics, Department of Radiology, Iowa City (United States)

    2004-12-01

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

  2. Displaced Anterior Column Acetabular Fracture: Closed Reduction and Percutaneous CT-Navigated Fixation

    Energy Technology Data Exchange (ETDEWEB)

    Huegli, R.W.; Staedele, H.; Messmer, P.; Regazzoni, P.; Steinbrich, W.; Gross, T. [Univ. Hospital of Basel (Switzerland). Dept. of Radiology

    2004-10-01

    The purpose of this study is to demonstrate the feasibility of computer-tomography-navigated closed reduction and percutaneous fixation (CRPF) in a patient with an externally rotated left acetabular fracture. After a follow-up of 18 months the patient was pain-free and had a normal range of motion in both hip joints. Radiologically, the fracture was fully consolidated, remodelled, and there were no signs of osteoarthritis. To our knowledge, CT-navigated CRPF of a rotated acetabular fracture has not been reported before. Further studies regarding the feasibility of the method are warranted(CRPF)

  3. Thin hard crest on the edge of ceramic acetabular liners accelerates wear in edge loading.

    Science.gov (United States)

    Sanders, Anthony P; Dudhiya, Parth J; Brannon, Rebecca M

    2012-01-01

    Ceramic acetabular liners may exhibit a small, sharp crest-an artifact of discontinuous machining steps--at the junction between the concave spherical surface and the interior edge. On 3 ceramic liners, this crest was found to form a 9° to 11° deviation from tangency. Edge loading wear tests were conducted directly on this crest and on a smoother region of the edge. The crest elicited 2 to 15 times greater volumetric wear on the femoral head. The propensity of the crest to rapidly (machining protocols might be a root cause of stripe wear and squeaking in ceramic acetabular bearings.

  4. 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

  5. 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.)

  6. 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.

  7. 中年患者生物型假体全髋置换178例:7年随访资料回顾分析%Retrospective research on the effect of cementless prosthesis in total hip replacement of 178 middle aged patients during 7-year follow-up

    Institute of Scientific and Technical Information of China (English)

    李强; 唐际存; 王锐英; 贝朝涌; 肖颖; 辛林伟

    2010-01-01

    BACKGROUND: Total hip replacement in middle-aged patients is challenging regarding restoration and survival,because these patients are more active than old patients.OBJECTIVE: To retrospectively investigate whether a cementless prosthesis could restore hip function,decrease osteolysis,wear,and enhance prosthesis survival in middle-aged patients.METHODS: Clinical and radiological evaluations of patients undergoing single-side total hip replacement with cement and cementless prosthesis were analyzed preoperatively as well as at 6 months,1,4 and 7 years postoperatively.The outcomes of total hip replacement were assessed using Harris hip scores and survival rate.End point was loosening or revision of the femoral component for any reason.RESULTS AND CONCLUSION: Cementless prosthesis had gained better Harris hip scores than that of cement prosthesis group at 6 months,1,4 and 7 years postoperatively(P < 0.05).The survival rate was greater in cementless prosthesis compared with cement prosthesis during 7-year follow-up(P < 0.05).Results have suggested that cementless prosthesis achieves high rate of functional restoration and a low rate of complications in middle-aged patients following total hip replacement.%背景:中年患者全髋关节置换后的恢复及假体生存率问题一直以来是一个比较棘手的问题,因为此组患者置换后对关节活动度的要求较老年患者的更高.目的:回顾性分析生物型假体在中年患者全髋关节置换后是否能促进功能恢复,减少骨质疏松及磨损,延长假体寿命.方法;选择以骨水泥型和非骨水泥型假体行单侧伞髋关节置换的中年患者,对该组患者分别于置换前、置换后6个月,1年,4年及7年的临床症状及影像学检查进行随访.以Harris髋关节评分及生存率评价伞髋关节置换效果,以任何原因形成的松动或翻修时间为截尾时间.结果与结论:非骨水泥型假体置换后6个月,1年,4年及7年的Harris评分明

  8. 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.

  9. 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...

  10. Acetabular allograft reconstruction in total hip arthroplasty. Part I: Current concepts in biomechanics.

    Science.gov (United States)

    Stiehl, J B

    1991-04-01

    Allograft reconstruction has become an essential tool for restoration of acetabular bone stock lost in failed total hip arthroplasty or resected in tumor reconstruction. This first segment of a two-part review will discuss the current status of allograft applications, together with pertinent biologic and biochemical aspects. Part II will address surgical considerations and recent clinical experience.

  11. 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

  12. A prospective comparative study of cementless total hip arthroplasty and hip resurfacing in patients under the age of 55 years: a ten-year follow-up.

    Science.gov (United States)

    Haddad, F S; Konan, S; Tahmassebi, J

    2015-05-01

    The aim of this study was to evaluate the ten-year clinical and functional outcome of hip resurfacing and to compare it with that of cementless hip arthroplasty in patients under the age of 55 years. Between 1999 and 2002, 80 patients were enrolled into the study: 24 were randomised (11 to hip resurfacing, 13 to total hip arthroplasty), 18 refused hip resurfacing and chose cementless total hip arthroplasty with a 32 mm bearing, and 38 insisted on resurfacing. The mean follow-up for all patients was 12.1 years (10 to 14). Patients were assessed clinically and radiologically at one year, five years and ten years. Outcome measures included EuroQol EQ5D, Oxford, Harris hip, University of California Los Angeles and University College Hospital functional scores. No differences were seen between the two groups in the Oxford or Harris hip scores or in the quality of life scores. Despite a similar aspiration to activity pre-operatively, a higher proportion of patients with a hip resurfacing were running and involved in sport and heavy manual labour after ten years. We found significantly higher function scores in patients who had undergone hip resurfacing than in those with a cementless hip arthroplasty at ten years. This suggests a functional advantage for hip resurfacing. There were no other attendant problems.

  13. 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...

  14. 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.

  15. 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...

  16. Experimental study on treatment of acetabular anterior column fractures: applyment of a minimally invasive percutaneous lag screw guide apparatus

    OpenAIRE

    Zhang, Li-hai; Zhang, Li-cheng; Si, Qing-hua; Gao, Yuan; Su, Xiu-Yun; Zhao, Zhe; Tang, Pei-Fu

    2016-01-01

    Background The aim of this study was to design a new minimally invasive percutaneous lag screw guide apparatus and to verify its adjuvant treatment of acetabular anterior column fracture on pelvis specimens. Methods This guide apparatus was self-developed based on the principles of “two points form a line” and “Rectangle”. Using C-arm fluoroscopy, this guide apparatus was used to conduct minimally invasive percutaneous lag screw internal fixation of acetabular anterior column fractures. Ten h...

  17. Quantitative measures of damage to subchondral bone are associated with functional outcome following treatment of displaced acetabular fractures.

    Science.gov (United States)

    Lubovsky, Omri; Kreder, Michael; Wright, David A; Kiss, Alex; Gallant, Aimee; Kreder, Hans J; Whyne, Cari M

    2013-12-01

    Current analysis of displaced acetabular fractures is limited in its ability to predict functional outcome. This study aimed to (1) quantify initial acetabular damage following acetabular fracture through measurement of subchondral bone density and fracture lines, and (2) evaluate associations between acetabular damage and functional outcomes following fracture. Subchondral bone intensity maps were created for 24 patients with unilateral acetabular fractures. Measures of crack length and density differences between corresponding regions in the fractured acetabuli, normalized by the unfractured side, were generated from preoperative CT images. Damage measures were compared to quality of life survey data collected for each patient at least 2 years post-injury (Musculoskeletal Functional Assessment [MFA] and Short Form-36 [SF-36], with specific focus on parameters that best describe patients' physical health). CT image quantification of initial damage to acetabular subchondral bone was associated with functional outcome post-injury. In general, damage as quantified through differences in density in the superior dome region (zones 8 and 12) and the central anterior region of the acetabulum (zone 3) were found to be the strongest significant predictors of functional outcome (adjusted R(2) = 0.3-0.45, p fractures toward improving clinical prognoses.

  18. Abductor weakness and stresses around acetabular components of total hip arthroplasty: a finite element analysis

    OpenAIRE

    Sutherland, A. G.; D’Arcy, S.; Smart, D; Ashcroft, G. P.

    1999-01-01

    Abductor weakness, and the resulting Trendelenburg gait, after total hip arthroplasty is believed to be associated with a poor long-term outcome. We have constructed a two-dimensional finite element analysis using load cases to mimic this abductor weakness. The finite element analysis demonstrates slightly increased stresses, particularly at the bone-cement interface in the DeLee-Charnley zone I, which does not seem sufficient to explain the adverse effect of abductor weakness.

  19. 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

  20. Pelvic, acetabular and hip fractures: What the surgeon should expect from the radiologist.

    Science.gov (United States)

    Molière, S; Dosch, J-C; Bierry, G

    2016-01-01

    Pelvic ring fractures when caused by trauma, either violent or in demineralized bone, generally consist of injuries in both the anterior (pubic symphysis and rami) and posterior (iliac wing, sacrum, sacroiliac joint) portions. Injury classifications are based on injury mechanism and pelvic stability, and are used to determine treatment. Acetabular fractures, associated or not to pelvic ring disruption, are classified on the basis of fracture line, into elementary fractures of the acetabular walls, columns and roof, and into complex fractures. Fractures of the proximal end of the femur occur often on demineralized bone following low-energy trauma. The fractures are categorized by anatomic location (neck, trochanter and subtrochanteric region) and degree of displacement. These variables determine the risk of osteonecrosis of the femoral head, which is the main complication of such fractures.

  1. 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.

  2. Arthroscopic excision of acetabular osteoid osteoma in a 7-year-old patient.

    Science.gov (United States)

    Aşık, Mehmet; Erşen, Ali; Polat, Gökhan; Bilgili, Fuat; Tunalı, Onur

    2015-11-01

    The purpose of this study was to present the case report of a 7-year-old patient who was treated with hip arthroscopy for an acetabular osteoid osteoma. A 7-year-old patient was referred to our clinic with hip pain. In the assessment of the patient, an acetabular osteoid osteoma was detected in his right hip; it was adjacent to his triradiate cartilage. An arthroscopic surgery was planned as an alternative to open safe hip dislocation. The osteoid osteoma was completely removed with hip arthroscopy. Postoperative CT scanning and histopathological analysis confirmed the diagnosis. Exposure of the acetabulum can be problematic in paediatric patients due to the potential risks of open safe dislocation. Hip arthroscopy can safely be used for benign hip lesions in paediatric patients. Level of evidence Case report, Level V.

  3. 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%).

  4. ROLE OF COMPUTED TOMOGRAPHY AND 3D RECONSTRUCTIONS IN PELVIC RIM AND ACETABULAR FRACTURES

    Directory of Open Access Journals (Sweden)

    Somasekhar

    2015-03-01

    Full Text Available To determine the role of computed tomography and 3D Reconstructions in classification of pelvic rim and acetabular fractures and assessing possible changes in fracture classification . We collected retrospective information in a period of 18 months in our institution , of patients with pelvic injuries considering --- demographic data , radiological examination performed and the moment when it was performed , fracture classification and management . In 12 cases ( 54% there were isolated pelvic rim fr actures and 7 cases of isolated acetabular fractures ( 32% and 3 cases ( 14% involving both . After the CT scan was obtained , the initial classification was changed in five cases ( 22 . 7% . Tridimensional CT based modeling is very helpful in the classificati on of pelvic fractures and is a complement of the plain X - ray .

  5. 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.

  6. 大臼杯在髋臼骨缺损患者的髋关节翻修术中的应用%Application of jumbo cups for acetabular deficiencies in hip revision procedures used in acetabulum defects of the hip revision procedures

    Institute of Scientific and Technical Information of China (English)

    王北岳; 周利武; 张志强; 郭亭; 赵建宁

    2014-01-01

    Objective To investigate the application of jumbo acetabular cups for Paprosky type II and type III A acetabular deifciencies after total hip arthroplasty ( THA ).Methods The clinical data of 24 patients who were diagnosed as acetabular deifciencies of Paprosky type II or type III A after THA from March 2007 to May 2014 were retrospectively analyzed. There were 13 males and 11 females, whose average age was 61.46 years old ( range: 34-77 years ). As to the reason of acetabular revision, there were 21 cases caused by aseptic loosening, 2 cases by habitual hip dislocation and 1 case by low toxicity infection. Primary and unilateral revision was performed on all the patients. Cemented acetabular prostheses were used in 11 cases, cementless acetabular prostheses in 10 cases and artiifcaial femoral head arthrolasty in 3 cases. According to the Paprosky acetabular defect classiifcation, there were 7 hips of type II A, 6 hips of type II B, 5 hips of type II C and 6 hips of type III A. Jumbo acetabular cups or combined with bone grafts were used in acetabular revision with prostheses. For the patients with acetabular deifciencies of Paprosky type II, the acetabulum was reamed and enlarged on the premise that the stability of the prosthesis was not affected, and then morselized bone graft was performed or the acetabular prosthesis with a jumbo cup was directly put in. For the patients with acetabular deifciencies of Paprosky type III A, an appropriate amount of compacted and morselized bone graft was used. Structural bone graft or the acetabular notch sealing was carried out, so as to increase the bone mass. The implantation technique through the center of the high ball could be directly adopted, with jumbo acetabular cups embedded. The problems of the balance of both lower limbs and the eccentricity could be handled by adjusting the length of the prosthetic handle and neck. A regular follow-up was carried out after the operation. The Harris hip score and Visual Analogue

  7. 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.

  8. 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.

  9. USING TRABECULAR METAL AUGMENTS FOR TOTAL HIP REPLACEMENT IN PATIENTS AFTER ACETABULAR FRACTURES

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    R. M. Tikhilov

    2011-01-01

    Full Text Available The authors presented the experience of treatment of two patients with hip arthritis after acetabular fracture. Both patients were treated with total hip replacement. During the operation, to manage posterior-superior bone defects of the acetabulum, augments of trabecular metal were used. Pain and limitation of motions in hip were indications for operative treatment. After a year of follow up there was no pain in hip; also recovery of motion and improved quality of life were observed.

  10. Selection of allografts for impaction bone grafting for bone defect reconstruction on the acetabular side

    Institute of Scientific and Technical Information of China (English)

    XU Zheng-jian; HE Rong-xin

    2010-01-01

    Objective To review the choices of allografts for bone defect reconstruction in acetabular revision surgery using the technique of impaction bone grafting.Data sources The data cited in this review were mainly obtained from articles listed in PubMed that were published from January 1993 to July 2009. The search terms were "impaction bone grafting", "particle size", "mechanical property"and "biological behavior".Study selection Articles relevant to the choices of allografts and their results for bone defect reconstruction on the acetabular side were selected.Results Different choices of allografts, including the particle size, process of irradiation or fat reduction, composition and particle grade, are made to improve the survival rate of a prosthesis in acetabular revision surgery. This review,which compares both mechanical and biological factors, summarizes the experimental and clinical results for different techniques.Conclusions Fresh frozen cancellous allografts with particle sizes ranging from 7 to 10 mm are a favorable choice for reconstruction of bone defects of American Academy of Orthopedic Surgeons (AAOS) types Ⅱ (cavitary defect) and Ⅲ(combined cavitary and segmental defect) on the acetabular side. A fat-reducing procedure with saline or solvent/detergent is controversial. Adding autologous marrow into irradiated allografts, which provides reliable mechanical stability and biological safety, may be a substitute for fresh frozen allografts. Cortical bone can be a supplementary material in cases of insufficiency of cancellous allografts. Cartilage should be excluded from the graft material. Further research is required to demonstrate the best particle grade, and randomized controlled trials in clinical practice are required to obtain more information about the selection of allografts.

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

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    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.

  12. Three-Dimensional Analysis of the Contact Pattern between the Cortical Bone and Femoral Prosthesis after Cementless Total Hip Arthroplasty

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    Hiroshi Wada

    2016-01-01

    Full Text Available The cementless stem Excia (B. Braun, Melsungen, Germany implant has a rectangular cross-sectional shape with back-and-forth flanges and a plasma-sprayed, dicalcium phosphate dihydrate coating from the middle to proximal portion to increase initial fixation and early bone formation. Here, the conformity of the Excia stem to the femoral canal morphology was three-dimensionally assessed using computed tomography. Forty-three patients (45 hips were examined after primary total hip arthroplasty with a mean follow-up of 27 ± 3 months (range: 24–36 months. Spot welds occurred at zone 2 in 16 hips and at zone 6 in 24 hips, with 83% (20/24 hips of those occurring within 3 months after surgery. First- (n=12 hips, second- (n=32, and third- (n=1 degree stress shielding were observed. The stem was typically in contact with the cortical bone in the anterolateral mid-portion (100% and posteromedial distal portions (85%. Stress shielding did not progress, even in cases where the stems were in contact with the distal portions. The anterior flange was in contact with the bone in all cases. The stability of the mid-lateral portion with the dicalcium phosphate dihydrate coating and the anterior flange may have inhibited the progression of stress shielding beyond the second degree.

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

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    Đurović Aleksandar

    2006-01-01

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

  14. Cementless total hip arthroplasty with modified oblique femoral shortening osteotomy in Crowe type IV congenital hip dislocation.

    Science.gov (United States)

    Kiliçoğlu, Onder İ; Türker, Mehmet; Akgül, Turgut; Yazicioğlu, Onder

    2013-01-01

    Midterm results of cementless total hip arthroplasty in patients with Crowe type IV congenital dislocation of the hip were evaluated. A modified oblique subtrochanteric shortening osteotomy was used in all patients. A cylindrical femoral stem was used in all patients to stabilize the osteotomy. Mean follow-up was 82 months in 20 hips of 16 patients. Mean Merle D'Aubigné pain score increased from 2.52 to 5.65 points, function score improved from 4.0 to 5.3 points, and mobility score improved from 3.95 to 5.35. Mean greater trochanter height relative to the estimated hip center was 6.8 ± 2.0 cm preoperatively and -1 ± 0.2 cm postoperatively. Complications were dislocations in 3 patients, which were successfully managed without redislocation and fracture of greater trochanter in 3 patients, which healed uneventfully in 2 but with residual Trendelenburg gait in one. Total hip arthroplasty with modified oblique subtrochanteric shortening osteotomy is an effective technique for the treatment for Crowe type IV hip dislocation.

  15. Optimization of custom cementless stem using finite element analysis and elastic modulus distribution for reducing stress-shielding effect.

    Science.gov (United States)

    Saravana Kumar, Gurunathan; George, Subin Philip

    2017-02-01

    This work proposes a methodology involving stiffness optimization for subject-specific cementless hip implant design based on finite element analysis for reducing stress-shielding effect. To assess the change in the stress-strain state of the femur and the resulting stress-shielding effect due to insertion of the implant, a finite element analysis of the resected femur with implant assembly is carried out for a clinically relevant loading condition. Selecting the von Mises stress as the criterion for discriminating regions for elastic modulus difference, a stiffness minimization method was employed by varying the elastic modulus distribution in custom implant stem. The stiffness minimization problem is formulated as material distribution problem without explicitly penalizing partial volume elements. This formulation enables designs that could be fabricated using additive manufacturing to make porous implant with varying levels of porosity. Stress-shielding effect, measured as difference between the von Mises stress in the intact and implanted femur, decreased as the elastic modulus distribution is optimized.

  16. 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.

  17. 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

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    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

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

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    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

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

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    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.

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

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    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.)

  1. Inversion of the acetabular labrum triggers rapidly destructive osteoarthritis of the hip: representative case report and proposed etiology.

    Science.gov (United States)

    Fukui, Kiyokazu; Kaneuji, Ayumi; Fukushima, Mana; Matsumoto, Tadami

    2014-12-01

    The pathophysiology of rapidly destructive osteoarthritis (OA) of the hip is unknown. This study documented cases of inversion of the acetabular labrum, which has clinicoradiologic features similar to those of initial-stage rapidly destructive hip OA. Our study was based on a prospective review of data for 9 patients with rapidly destructive hip OA. Intraoperative findings showed that the anterosuperior portion of the acetabular labrum had inverted into the articular space, along with many fragments of articular cartilage, in all patients. Subchondral insufficiency fractures of the femoral heads were seen just under the inverted labra in 8 of the 9 patients. Inversion of the acetabular labrum may be involved in rapid joint-space narrowing and subchondral insufficiency fracture in rapidly destructive hip OA.

  2. 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。

  3. 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.

  4. Occult internal iliac arterial injury identified during open reduction internal fixation of an acetabular fracture: a report of two cases.

    Science.gov (United States)

    Chaus, George W; Heng, Marilyn; Smith, Raymond M

    2015-07-01

    We present two cases of occult internal iliac arterial injury identified during operative reduction of a widely displaced posterior column posterior wall acetabular fracture. This complication was not recognised until reduction of the column fracture. There were no preoperative signs or symptoms indicative of a vascular injury. These cases emphasise the heightened awareness one must have when treating widely displaced posterior column fractures of the acetabulum, especially those fractures with extension into the greater sciatic notch, as previously formed clot can become dislodged and hemostasis lost. We also present management options when this complication occurs. We believe any surgeon treating acetabular fractures should be aware of this serious and potentially fatal complication.

  5. 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.

  6. Fucntional and Radiological Outcome of Surgical Management of Acetabular Fractures in Tertiary Care Hospital

    Science.gov (United States)

    Taufiq, Intikhab; Najjad, Muhammad Kazim Raheem; Khan, Naveed; Zia, Osama Bin

    2016-01-01

    Purpose Acetabular fractures are mainly caused by trauma and the incidence is rising in developing countries. Initially these fractures were managed conservatively, due to lack of specialized and dedicated acetabulum surgery centres. Our aim is to study the radiological and functional outcomes of surgical management of acetabular fractures in tertiary care hospital. Materials and Methods Total 50 patients were enrolled. The patients with acetabular fractures were enrolled between the years 2012 to 2014. Patients were evaluated clinically with Harris hip score (HHS) and radiologically with Matta outcome grading. The factors examined include age, gender, fracture pattern, time between injury and surgery, initial displacement and quality of reduction on the final outcome. Results There were 34 males and 16 females. Mean age was 44.20±11.65 years while mean duration of stay was 9.28±2.36 days. Duration of follow-up was 24 months. Most common mechanism of injury was motor vehicle accident (n=37, 74.0%). Open reduction and internal fixation of fractures were performed using reconstruction plates. Mean HHS at 24 months was 82.36±8.55. The clinical outcome was acceptable (excellent or good) in 35 (70.0%) cases and not acceptable (fair or poor) in 15 (30.0%) cases. The radiological outcome was anatomical in 39 (78.0%) cases, congruent in 5 (10.0%) cases, incongruent in 6 (12.0%) cases. Conclusion Study results indicated that mechanism of injury, time between injury and surgery, initial degree of displacement and quality of reduction had significant effect on functional as well as radiological outcome. PMID:28097111

  7. Evaluating the accuracy of wear formulae for acetabular cup liners.

    Science.gov (United States)

    Wu, James Shih-Shyn; Hsu, Shu-Ling; Chen, Jian-Horng

    2010-02-01

    This study proposes two methods for exploring the wear volume of a worn liner. The first method is a numerical method, in which SolidWorks software is used to create models of the worn out regions of liners at various wear directions and depths. The second method is an experimental one, in which a machining center is used to mill polyoxymethylene to manufacture worn and unworn liner models, then the volumes of the models are measured. The results show that the SolidWorks software is a good tool for presenting the wear pattern and volume of a worn liner. The formula provided by Ilchmann is the most suitable for computing liner volume loss, but is not accurate enough. This study suggests that a more accurate wear formula is required. This is crucial for accurate evaluation of the performance of hip components implanted in patients, as well as for designing new hip components.

  8. Hip Arthroscopy for Incarcerated Acetabular Labrum following Reduction of Traumatic Hip Dislocation: Three Case Reports

    Science.gov (United States)

    Hwang, Jung-Mo; Lee, Woo-Yong; Noh, Chang-Kyun; Zheng, Long

    2016-01-01

    Traumatic hip fracture-dislocations are associated with chondral and labral pathology as well as loose bodies that can be incarcerated in the hip joint. Incarceration, such as interposed labrum between acetabulum and femoral head that is not readily visualized preoperatively, is a rare but important cause of pain and can potentially be a source for early degeneration and progression to osteoarthritis. We present three cases, arthroscopic surgery of incarcerated acetabular osseo-labral fragment following reduction of traumatic hip fracture-dislocation. PMID:27777919

  9. 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

  10. 3D Printing Aids Acetabular Reconstruction in Complex Revision Hip Arthroplasty

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    Andrew J. Hughes

    2017-01-01

    Full Text Available Revision hip arthroplasty requires comprehensive appreciation of abnormal bony anatomy. Advances in radiology and manufacturing technology have made three-dimensional (3D representation of osseous anatomy obtainable, which provide visual and tactile feedback. Such life-size 3D models were manufactured from computed tomography scans of three hip joints in two patients. The first patient had undergone multiple previous hip arthroplasties for bilateral hip infections, resulting in right-sided pelvic discontinuity and a severe left-sided posterosuperior acetabular deficiency. The second patient had a first-stage revision for infection and recurrent dislocations. Specific metal reduction protocols were used to reduce artefact. The images were imported into Materialise MIMICS 14.12®. The models were manufactured using selective laser sintering. Accurate templating was performed preoperatively. Acetabular cup, augment, buttress, and cage sizes were trialled using the models, before being adjusted, and resterilised, enhancing the preoperative decision-making process. Screw trajectory simulation was carried out, reducing the risk of neurovascular injury. With 3D printing technology, complex pelvic deformities were better evaluated and treated with improved precision. Life-size models allowed accurate surgical simulation, thus improving anatomical appreciation and preoperative planning. The accuracy and cost-effectiveness of the technique should prove invaluable as a tool to aid clinical practice.

  11. 3D Printing Aids Acetabular Reconstruction in Complex Revision Hip Arthroplasty

    Science.gov (United States)

    DeBuitleir, Cathal; Soden, Philip; O'Donnchadha, Brian; Tansey, Anthony; Abdulkarim, Ali; McMahon, Colm; Hurson, Conor J.

    2017-01-01

    Revision hip arthroplasty requires comprehensive appreciation of abnormal bony anatomy. Advances in radiology and manufacturing technology have made three-dimensional (3D) representation of osseous anatomy obtainable, which provide visual and tactile feedback. Such life-size 3D models were manufactured from computed tomography scans of three hip joints in two patients. The first patient had undergone multiple previous hip arthroplasties for bilateral hip infections, resulting in right-sided pelvic discontinuity and a severe left-sided posterosuperior acetabular deficiency. The second patient had a first-stage revision for infection and recurrent dislocations. Specific metal reduction protocols were used to reduce artefact. The images were imported into Materialise MIMICS 14.12®. The models were manufactured using selective laser sintering. Accurate templating was performed preoperatively. Acetabular cup, augment, buttress, and cage sizes were trialled using the models, before being adjusted, and resterilised, enhancing the preoperative decision-making process. Screw trajectory simulation was carried out, reducing the risk of neurovascular injury. With 3D printing technology, complex pelvic deformities were better evaluated and treated with improved precision. Life-size models allowed accurate surgical simulation, thus improving anatomical appreciation and preoperative planning. The accuracy and cost-effectiveness of the technique should prove invaluable as a tool to aid clinical practice. PMID:28168060

  12. 髋臼肿瘤的保肢治疗%Limb-salvage surgery for acetabular tumors

    Institute of Scientific and Technical Information of China (English)

    徐万鹏

    2013-01-01

    Surgical treatment of acetabular tumors referred to extensive amputation or limb salvage therapy for the treatments of acetabulum and its surrounding bone destruction caused by primary malignant bone tumors or aggressive benign bone tumors. The surgical treatment of malignant tumors before 1991 was mainly half pelvic amputation. From March 1991 to April 2003, local resection and re-implantation using allograft pelvis or inactivated tumor bone shell reconstruction were performed. Limb salvage was achieved. Half of the patients were cured with weight-bearing walking with a cane or crutches. The authors have been using their own designed artificial pelvic prosthesis for reconstruction after 2003. They pointed out that mounting should be on pressure transforming line. The prosthesis and the host bone were fixed without loosening during the follow-up. The majority of patients have good hip function as the contralateral hip. Patients’ gait may be limp, but could be able to walk independently. With the diagnosis and treatment practice for years, pelvic tumors were not so uncommon and the treatment was challenging. The pathology of acetabular tumor was complex and diverse, and it was tumors nearing multiple organs that made it difficult to diagnose early and misdiagnosis and wrong treatment occurred. In accordance with the nature of the tumor, tumor size, amputation or limb salvage could be used. It was difficult to resect tumors and limb salvage was a type of rescue methods. Fully preoperative preparation and postoperative care should be emphasized. The disease could be cured with assistant chemotherapy and radiotherapy.

  13. Posterior acetabular column and quadrilateral plate fractures: fixation with tension band principles.

    Science.gov (United States)

    Aly, Tarek A; Hamed, Hany

    2013-07-01

    Acetabular fractures can be classified into 5 simple and 5 associated fracture patterns. A significant amount of variation and complexity exists in these fractures patterns. Fractures of the posterior wall are the most common acetabular fractures. Comminution of the quadrilateral plate adds to fracture instability, and more rigid and stable internal fixation is mandatory. The goal of this study was to assess the results of reconstruction of comminuted posterior wall fractures of the acetabulum associated with quadrilateral plate fractures using the tension band technique. Twelve patients (9 men and 3 women) were included in the study. Mean patient age was 38.6 years (range, 24-47 years). Minimum follow-up was more than 2 years postoperatively. Reconstruction of the fracture included anatomic reduction of the fracture and fixation with a buttress plate for the posterior column and a prebent one-third tubular plate for the quadrilateral plate fracture. Clinical results were excellent in 58% of patients and good in 17% of patients. Radiologic results were excellent in 50% of patients and good in 17% of patients. Radiologically, based on the fracture gap postoperatively, 8 (66%) patients showed anatomic reduction, 2 (17%) showed good reduction, and 2 (17%) showed poor reduction. The study confirms that this method of reconstruction facilitates accurate and firm reduction of displaced posterior wall fractures of the acetabulum.

  14. 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.

  15. Thrombotic risk assessment questionary helps increase the use of thromboprophylaxis for patients with pelvic and acetabular fractures

    Directory of Open Access Journals (Sweden)

    Haili Wang

    2012-01-01

    Conclusion: The assessment table can significantly improve the use of thromboprophylaxis after pelvic and acetabular fractures, which will likely reduce the incidence of DVT. Developing individual hospital prophylaxis strategy is an effective way to determine whether hospitalized patients should receive pharmacologic and/or mechanical prophylaxis or not.

  16. 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

  17. Influence of ingrowth regions on bone remodelling around a cementless hip resurfacing femoral implant.

    Science.gov (United States)

    Haider, Ifaz T; Speirs, Andrew D; Beaulé, Paul E; Frei, Hanspeter

    2015-01-01

    Hip resurfacing arthroplasty is an alternative to traditional hip replacement that can conserve proximal bone stock and has gained popularity but bone resorption may limit implant survival and remains a clinical concern. The goal of this study was to analyze bone remodelling patterns around an uncemented resurfacing implant and the influence of ingrowth regions on resorption. A computed tomography-derived finite element model of a proximal femur with a virtually implanted resurfacing component was simulated under peak walking loads. Bone ingrowth was simulated by six interface conditions: fully bonded; fully friction; bonded cap with friction stem; a small bonded region at the stem-cup intersection with the remaining surface friction; fully frictional, except for a bonded band along the distal end of the cap and superior half of the cap bonded with the rest frictional. Interface condition had a large influence on remodelling patterns. Bone resorption was minimized when no ingrowth occurred at the bone-implant interface. Bonding only the superior half of the cap increased bone resorption slightly but allowed for a large ingrowth region to improve secondary stability.

  18. Role of MRI in the diagnosis of insufficiency fractures of the sacrum and acetabular roof

    Energy Technology Data Exchange (ETDEWEB)

    Grangier, C.; Garcia, J.; Howarth, N.R. [Departement de Radiologie, Division de Radiodiagnostic, Hopital Cantonal Universitaire de Geneve, CH-1211 Geneva 14 (Switzerland); May, M. [Departement de Radiologie, Division de Radio-Oncologie, Hopital Cantonal Universitaire de Geneve, CH-1211 Geneva 14 (Switzerland); Rossier, P. [Departement de Radiologie, Division de Medecine Nucleaire, Hopital Cantonal Universitaire de Geneve, CH-1211 Geneva 14 (Switzerland)

    1997-09-01

    Twenty patients with sacral and acetabular roof insufficiency fractures were reviewed retrospectively. There were 16 women (80%) and 4 males (age range 48-86 years, excluding an 8-year-old boy). Thirteen patients had a known tumour, and nine had received pelvic irradiation. All patients, except one who was asymptomatic, presented with low back or hip pain. In patients with a known tumor, metastases were suspected. Plain radiography (20), bone scintigrams (16), MR examinations (20), and bone densitometry (14) were performed. Nine patients also each had a CT scan. Results and conclusions. In three cases the CT scan performed 10-25 days after onset of symptoms was interpreted as normal. MR examination performed a few days after the CT scan showed in each of these three patients a fracture line with a band of edema. Scintigraphy was very sensitive, but the H-shaped pattern of sacral uptake, specific for an insufficiency fracture, was detected in only three of 16 cases. The earliest MR sign was medullary edema, seen as early as 18 days after the onset of symptoms. On spin echo (SE) T1-weighted images (T1WI), the hypointense signal of edema could mask a fracture line. On SE T2WI the fracture line could be detected within the hyperintense edema (10 of 17 patients with examinations including SE T2WI). However, in four patients a fracture of the sacrum was not seen on T2WI, these having been obtained in the axial plane. For this reason, intravenous gadolinium was injected, revealing a fracture line in 12 of 14 examinations, or fat suppression sequences were performed, revealing a fracture line in five of five cases. The total number of fractures detected was 17 [15 fractures of the sacrum (bilateral in 10 cases) and two of the acetabular roof]. At a later stage, the edema resolved and the fracture was clearly seen. The two cases of fracture of the acetabular roof were easily recognized at MRI, particularly in the sagittal plane. (orig./AJ). With 5 figs., 2 tabs.

  19. The influence of contact ratio and its location on the primary stability of cementless total hip arthroplasty: A finite element analysis.

    Science.gov (United States)

    Reimeringer, M; Nuño, N

    2016-05-03

    Cementless hip stems are fixed to the surrounding bone by means of press-fit. To ensure a good press-fit, current surgical technique specifies an under-reaming of the bone cavity using successively larger broaches. Nevertheless, this surgical technique is inaccurate. Several studies show that the contact ratio (percentage of stem interface in contact with bone) achieved after surgery can vary between 20% and 95%. Therefore, this study aimed to investigate the influence of the contact ratio and its location on the primary stability of a cementless total hip arthroplasty using finite element analysis. A straight tapered femoral stem implanted in a composite bone was subjected to stair climbing. Micromotion of 7600 nodes at the stem-bone interface was computed for different configurations of contact ratios between 2% and 98%) along the hip stem. Considering the 15 configurations evaluated, the average micromotion ranges between 27μm and 54μm. The percentage of the porous interface of the stem having micromotion below 40μm that allows bone ingrowth range between 25-57%. The present numerical study shows that full contact (100%) between stem and bone is not necessary to obtain a good primary stability. The stem primary stability is influenced by both the contact ratio and its location. Several configurations with contact ratio lower than 100% and involving either the proximal or the cortical contact provide better primary stability than the full contact configuration. However, with contact ratio lower than 40%, the stem should be in contact with cortical bone to ensure a good primary stability.

  20. A feasibility study into the use of three-dimensional printer modelling in acetabular fracture surgery.

    Science.gov (United States)

    Yu, A W; Duncan, J M; Daurka, J S; Lewis, A; Cobb, J

    2015-01-01

    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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. A Modified Stoppa (Technique Approach for Treatment of Pediatric Acetabular Fractures

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    Mehmet Elmadag

    2013-01-01

    Full Text Available Pediatric acetabular fractures are rare, and anterior column fractures are even rarer. Generally, conservative treatment is applied. If there is displacement of more than 2 mm or findings of instability or fragments within the joint, then surgical treatment is applied. Anterior and posterior approaches may be used in surgical treatment. With pediatric patients, even greater care should be taken in the choice of surgery to be performed according to the fracture pattern to avoid postoperative triradiate cartilage damage. Therefore, minimally invasive surgery is more appropriate. We herein present a case of an acetabulum anterior column posterior hemitransverse fracture following a traffic accident, which was treated surgically using a modified Stoppa (technique approach.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. Uncemented Total Hip Replacement After Two Years of Neglected Hip Dislocation With Fracture of Posterior Column and Wall of the Acetabulum

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    DC

    2016-07-01

    Full Text Available Introduction Posterior hip dislocation of the hip with acetabular fracture is a challenging problem to treat. Such dislocations are associated with avascular necrosis of the femoral head if neglected. Managing such conditions with total hip replacement (THR is very difficult because of associated altered anatomy. Case Presentation We hereby report a two-year neglected hip dislocation with associated acetabular fracture successfully treated with uncemented THR. The patient was successfully treated with uncemented THR and experienced significant improvement in his functional status, with a Harris hip score of 82 at the two-year follow up. Radiologically, there were no radiolucent areas or osteolysis, with good consolidation of the bone graft. Conclusions A neglected hip dislocation with acetabular fracture can be managed satisfactorily with uncemented THR. Bone reconstruction using chunk grafts and use of cementless components ensures long-term survival and also preserves adequate bone stock for revision, especially in young patients.

  11. 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

  12. 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.

  13. 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.

  14. 662髋Ribbed假体中远期临床疗效观察%Medio/long-term clinical observation of 662 Ribbed anatomic cementless prosthesis

    Institute of Scientific and Technical Information of China (English)

    史庆轩; 李佩佳; 孙磊; 赵汉平; 胡宏伟; 罗永忠; 田敏; 刘明; 包健

    2012-01-01

    [Objective ] To evaluate the median and long - term clinical effect of the Ribbed anatomic cementless prosthesis. [Methods] A retrospective study was held. A total of 728 hip9 in 697 patients undergone THR with Ribbed anatomic cementless prosthesis were reviewed between July 1997 and September 2008, 662 hips in 606 patients were available for follow -up, the mean follow - up period were 7. 9 years (from 3 to 14 years) . [ Results] The mean Harris Hip Score increased from 35. 6 preoperatively to 91.4 postoperatively. Excellent and good function rate was 95. 7%. [Conclusion] Ribbed anatomic ce-menlless prosthesis is found to be well with good clinical effect in the median and long - term clinical observation.%[目的]评价Ribbed解剖型非骨水泥固定股骨假体的中远期临床应用效果.[方法]回顾性分析本科1997年7月~2008年9月应用解剖型非骨水泥固定股骨假体行全髋关节置换的病人697例共728髋.实际随访606例662髋,随访率90.9%.随访时间最短3年,最长14年,平均7.9年.所用假体均为Ribbed假体.[结果]Harris评分术前平均35.6分,术后平均91.4分,优良率95.7%,关节功能满意.随访X线片均未见明显透光线及假体移位,未发现股骨柄假体无菌性松动.[结论]Ribbed假体设计合理,特点显著,中远期效果满意,值得临床推广应用.

  15. 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

  16. 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.)

  17. Application of a shape-memory alloy internal fixator for treatment of acetabular fractures with a follow-up of two to nine years in China.

    Science.gov (United States)

    Liu, Xinwei; Xu, Shuogui; Zhang, Chuncai; Su, Jiacan; Yu, Baoqing

    2010-10-01

    Displaced acetabular fractures should be treated surgically. Over the past decade, surgical approaches to the acetabulum and the surgical technique for repair of common fracture patterns have advanced. Excellent outcomes after repair of these injuries can be achieved. The aim of this study was to assess the medium-term results of reconstruction of acetabular fractures by using shape-memory alloy designed by the authors. This is a retrospective review conducted at a level 1 trauma centre. From October 1999 to July 2009, 19 patients with acetabular fractures were treated with our patented Ni-Ti shape-memory alloy acetabular tridimensional memory alloy-fixation system (ATMFS). The ATMFS device was cooled with ice before implantation and then warmed to 40-50°C after implantation to produce balanced axial and compression forces that would stabilise the fracture three dimensionally. Our results are as follows; according to the D'Aubigne-Postel scoring system: Fifteen cases out of 19 (79%) achieved excellent or good clinical results. In two patients, late complications included avascular necrosis of the femoral head (ANFH) associated with posterior dislocation of the hip joint two years after the operation. We also observed two cases of grade II or III ectopic ossification, with good hip function, and one case of traumatic arthritis. In conclusion, these results demonstrate the effectiveness of the ATMFS device for the management of acetabular fracture. The device provides continuous compression of the fracture with minimal disruption to the local blood supply.

  18. Acetabular anatomy and the relationship with pelvic vascular structures. Implications in hip surgery.

    Science.gov (United States)

    Feugier, P; Fessy, M H; Béjui, J; Bouchet, A

    1997-01-01

    Most direct vascular trauma occurring during hip surgery results from injury to pelvic vascular structures which are not visible during the procedures of reaming, drilling holes or the fixation of screws. In this study, 5 pelves of fresh cadavers were injected with a radiopaque mixture and were visualised with a scanner according to 5 predetermined sections. Bone depth of the acetabulum was measured in each section. A calculation was made describing the minimal distance separating the inner cortex from the principal pelvic vessels. After an anatomic dissection of each pelvis, the relationship between the vessels and screws of the fixation cup, implanted identically on the quadranted acetabulum, was observed. The screws placed in the anterior and inferior quadrants and the center of the acetabulum endangered the external iliac v. and a. and the obturator pedicle. The depth of the periacetabular bone was greater in the superior and posterior quadrants. The inferior gluteal, pudendal and superior gluteal aa. were more than ten mm from the posterior wall. Conversely, the external iliac and obturator pedicles came in contact with the osseous surface on which they lay. A projection of the vessels on the acetabulum was made, and the reproducible character of the acetabular-quadrant system was verified. The superior quadrant offers all the characteristics of a vascular safe zone. A knowledge of these anatomic relationships explain vascular trauma in pelvic fractures and helps to prevent vascular injury in hip surgery.

  19. Results of Chiari pelvic osteotomy for acetabular dysplasia in adults; Association with bone scintigraphic findings

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Nobuo; Ozono, Kenji; Sugano, Nobuhiko; Takaoka, Kunio; Ono, Hiroo (Osaka Univ. (Japan). Faculty of Medicine)

    1993-02-01

    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.).

  20. 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

  1. 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.

  2. 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

  3. 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".

  4. 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.

  5. 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...

  6. Indirect reduction of posterior wall fragment using a suture anchor in acetabular posterior wall fracture with posterior labral root tear.

    Science.gov (United States)

    Yoo, Je-Hyun; Chang, Jun-Dong; Lee, Ho-Won

    2015-02-01

    Posterior wall fractures, which are the most common type of acetabulum fracture, are frequently accompanied with an avulsion tear of the posterior labral root as well as hip dislocation due to the injury mechanism. In the treatment of these fractures with an avulsed posterior labral root attached to posterior wall fragment, the use of a suture anchor can induce indirect reduction of a posterior wall fragment as well as direct repair of a labral root tear simultaneously. We describe the simple and efficient technique using a suture anchor in posterior wall acetabular fractures and surgical outcomes of two cases treated with this technique.

  7. 髋臼内壁截骨在成人发育不良髋关节置换中的应用:8例分析%Acetabular medial wall displacement osteotomy in total hip arthroplasty for treatment of adult hip hysplasia An 8-case analysis

    Institute of Scientific and Technical Information of China (English)

    过慧敏; 廖琦; 黄华斌

    2009-01-01

    The present study retrospectively analyzed 8 patients with hip dysplasia (8 hips) comprising 2 males and 6 females, aged 46 years old (range, 35-65 years old) who received treatment at the Department of Orthopedics, Second Affiliated Hospital of Nanchang University between September 2004 and November 2006. Preoperative radiographs and CT examination showed that all patients presented with sharp angle of affected hip > 45°, poor containment of femoral head, narrow joint space, and non-successive Shenton's line. Following Crowe classification, there were 5 cases (5 hips) of grade Ⅱ,and 3 cases (3 hips) of grade Ⅲ. Preoperative Harris hip score was 50 points (range, 44-62 points). Total hip arthroplasty was employed in each patient. Prosthesis was fixed by Cementless or cemented modes. Cementless fixation was applied in 6 hips and cemented fixation in 2 hips. Cementless prosthesis was used on the affected side in each patient. Replacement time, bleeding volume during surgery, hospital days post-surgery, Harris scores, and peri-operative complications were recorded.Simultaneously, post-surgery healing was observed. All 8 cases were followed up for an average period of 6 months. All patients exhibited well recovered joint function. No infection, sciatic nerve injury, dislocation of hip joint, fracture of femoral shaft, thrombosis of deep veins, or prosthesis loosening were found in any follow-up case. Six months after surgery, Harris hip score was 88 points (range, 86-94 points). Radiographs taken at 3 months post-surgery displayed the bone union of surgical region. All these findings suggest that acetabular medial wall displacement osteotomy in total hip arthroplasty produces obvious early- and middle-stage effects in treatment of hip dysplasia.%回顾性分析2004-09/2006-11南昌大学第二附属医院骨科收治的髋关节发育不良患者8例(8髋).男2例,女6例,年龄35~65岁,平均46岁;置换前行X射线摄片及CT检查,提示所

  8. Factors contributing to rapid wear and osteolysis in hips with modular acetabular bearings made of hylamer.

    Science.gov (United States)

    Scott, D L; Campbell, P A; McClung, C D; Schmalzried, T P

    2000-01-01

    There have been several reports of osteolysis associated with rapid wear of Hylamer. A detailed analysis of retrieved implants and tissues can identify factors contributing to rapid wear and osteolysis. The mean linear wear rate of 12 liners was 0.49 mm/y, and 11 of 12 hips had progressive retroacetabular osteolysis. The average patient age was 50 years, and the mean implantation time was 50 months. All liners were sterilized by gamma irradiation in air. There was an 11-month difference in the average shelf-life of the 3 liners that were white and those that were darker in color. The volumetric wear rate of the white liners was 30% less than that of the others, suggesting a difference in the wear resistance of the liners as a function of shelf life. The mean average surface roughness (Ra) and the mean maximum surface roughness (R(max)) of the femoral heads were increased 3-fold and 50-fold compared with typical values for unused femoral heads. Evidence of 3-body wear, such as metal particles embedded in the liners, was commonly present. The pattern of backside liner deformation and burnishing was consistent with relative motion between the liner and the shell. In addition to generating Hylamer wear particles, repetitive axial motion between the liner and shell could generate fluid pressure, which transmitted through holes in the acetabular shell could cause or contribute to the development of retroacetabular osteolysis. Hylamer particles of variable shape and size, consistent with generation by several wear modes, were isolated from periprosthetic tissues.

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

    Directory of Open Access Journals (Sweden)

    Massimiliano De Paolis

    2013-01-01

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

  10. Hydroxyapatite in total hip arthroplasty. Our experience with a plasma spray porous titanium alloy/hydroxyapatite double-coated cementless stem

    Science.gov (United States)

    Castellini, Iacopo; Andreani, Lorenzo; Parchi, Paolo Domenico; Bonicoli, Enrico; Piolanti, Nicola; Risoli, Francesca; Lisanti, Michele

    2016-01-01

    Summary Purpose Total hip arthroplasty could fail due to many factors and one of the most common is the aseptic loosening. In order to achieve an effective osseointegration and reduce risk of lossening, the use of cemented implant, contact porous bearing surface and organic coating were developed. Aim of this study was to evaluate clinical and radiological mid-term outcomes of a porous titanium alloy/hydroxyapatite double coating manufactured cementless femoral stem applied with “plasma spray” technique and to demonstrate the possibility to use this stem in different types of femoral canals. Methods Between January 2008 and December 2012, 240 consecutive primary total hip arthroplasties (THAs) were performed using a porous titanium alloy/hydroxyapatite double coating manufactured cementless femoral stem. 182 patients were examined: 136 were females (74.7%) and 46 males (25.2%); average age was 72 years old (ranging from 26 to 92 years old). For each patient, Harris Hip Scores (HHS) and Womac Scores were collected. All X-ray images were analyzed in order to demonstrate stem survival rate and subsidence. Results Harris Hip Score was good or excellent in 85% of the cases (average 90%) and mean WOMAC score was 97.5 (ranging from 73.4 to 100). No cases of early/late infection or periprosthetic fracture were noticed, with an excellent implant survival rate (100%) in a mean period of 40 months (ranging from 24 and 84 months). 5 cases presented acute implant dislocation, 2 due to wrong cup positioning in a dysplastic acetabulum and 3 after ground level fall. Dorr classification of femoral geometry was uses and the results were: 51 type A bone, 53 type B bone and 78 type C bone. Stem subsidence over 2 mm was considered as a risk factor of future implant loosening and was evidenced in 3 female patients with type C of Dorr classification. No radiolucencies signs around the proximally coated portion of stem or proximal reabsorption were visible during the radiographic

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

    Science.gov (United States)

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

    2014-10-01

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

  12. 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.

  13. Highly cross-linked polyethylene acetabular liners retrieved four to five years after revision surgery: a report of two cases.

    Science.gov (United States)

    Teeter, Matthew G; Naudie, Douglas D R; Charron, Kory D; Holdsworth, David W

    2010-08-01

    There is currently considerable interest in the use of highly cross-linked polyethylene (XLPE) acetabular liners for total hip arthroplasty (THA). In literature, only a single retrieval analysis of one type of XLPE liner implanted for greater than four years exists. The purpose of the present report is to quantify surface deviations in two XLPE liners implanted during revision THA and retrieved between four to five years after implantation. The two XLPE acetabular liners (Reflection, Smith and Nephew Inc., Memphis, TN) were retrieved from patients undergoing their second revision surgery, at 4.90 and 4.07 years. The retrieved liners and a new, non-implanted, unworn liner of the same size were scanned using micro-computed tomography (micro-CT). Articular surface deviation maps were created by comparing the retrievals to the unworn liner, based on the liner geometry obtained from micro-CT. The linear penetration rates were found to be 0.018 and 0.008 mm/year. Localized scratches and pits with deviations greater than 0.205 mm were also found on the articular surfaces of both liners. The XLPE liners retrieved from the two cases demonstrated low linear penetration rates. Regions with greater focal deviations were also apparent, likely due to third-body wear. The results are consistent with previously published clinical follow-ups of other XLPE liners.

  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. Hip flexor muscle size, strength and recruitment pattern in patients with acetabular labral tears compared to healthy controls.

    Science.gov (United States)

    Mendis, M Dilani; Wilson, Stephen J; Hayes, David A; Watts, Mark C; Hides, Julie A

    2014-10-01

    Acetabular labral tears are a source of hip pain and are considered to be a precursor to hip osteoarthritis. Hip flexor muscles contribute to hip joint stability and function but it is unknown if their size and function is altered in the presence of labral pathology. This study aimed to investigate hip flexor muscle size, strength and recruitment pattern in patients with hip labral pathology compared to control subjects. 12 subjects diagnosed with an unilateral acetabular labral tear were compared to 12 control subjects matched for age and gender. All subjects underwent magnetic resonance imaging (MRI) of their lumbo-pelvic region. Average muscle cross-sectional area (CSA) of the iliacus, psoas, iliopsoas, sartorius, tensor fascia latae and rectus femoris muscles were measured. Hip flexion strength was measured by an externally fixed dynamometer. Individual muscle recruitment pattern during a resisted hip flexion exercise task was measured by muscle functional MRI. Hip flexor muscle strength was found to be decreased in patients with labral pathology compared to control subjects (p  0.17) and recruitment pattern (all p > 0.53). Decreased hip flexor muscle strength may affect physical function in patients with hip labral pathology by contributing to altered gait patterns and functional tasks. Clinical rehabilitation of these patients may need to include strengthening exercises for the hip flexor muscles.

  16. Theoretical Implications of Periacetabular Osteotomy in Various Dysplastic Acetabular Cartilage Defects as Determined by Finite Element Analysis

    Science.gov (United States)

    Xu, Meng; Qu, Wenrui; Wang, Yanbing; Zhong, Lei; Zhu, Zhe; Li, Wei; Zhao, Xin; Wang, Jincheng; Sun, Yu

    2016-01-01

    Background Different extents and locations of acetabular cartilage defect have been supposed to be a major cause of undesirable outcomes of periacetabular osteotomy (PAO) in patients with developmental dysplasia of the hip (DDH). This study aimed to verify whether different locations of cartilage deficiency affect the biomechanical environment in a three-dimensional model utilizing finite element analysis (FEA). Material/Methods We developed 3 DDH models – DDH-1 (normal shape), DDH-2 (superior defect), and DDH-3 (anterosuperior defect) – by deforming from a normal hip model. We also developed 3 PAO models – PAO-1, PAO-2, and PAO-3 – through rotating osteotomized fragments. Results The maximum von Mises stress in the normal hip was 13.06 MPa. In the DDH-1 model, the maximum value on the load-bearing area decreased from 15.49 MPa pre-PAO to 14.28 MPa post-PAO, while stresses in the DDH-2 and DDH-3 models were higher than in the DDH-1 model, both pre-PAO and post-PAO (30.46 MPa to 26.04 MPa for DDH-2; 33.89 MPa to 27.48 MPa for DDH-3). Conclusions This study shows that, both pre- and post-PAO, different types of cartilage deficiency affect the biomechanical environment. Furthermore, in dysplastic hips, obtaining accurate three-dimensional information about the acetabular cartilage can contribute substantially to PAO decision making. PMID:28017958

  17. 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.

  18. Total hip arthroplasty vs. osteosynthesis in acute complex acetabular fractures in the elderly: Evaluation of surgical management and outcomes

    Directory of Open Access Journals (Sweden)

    Serafino Carta

    2017-01-01

    Full Text Available Objective: To retrospectively evaluate the open reduction internal fixation and total hip arthroplasty directions, results and complications associated with internal fixation in managing these fractures. Methods: In 8 years at 4 centers, 61 patients with associated acetabular fractures (Letournel classification were treated. The patients were divided into two groups. The total hip arthoplasty (THA group consisted of 30 patients, while the open reduction internal fixation group had 31 patients. The average age of the patients was 74.7 years. The following parameters were compared: the duration of surgery and hospitalization, the international unit of red blood cell concentrate transfusion, the time for the verticalization of the patient, perioperative complications, Harris hip score, and the short form (12 health survey. The clinical and radiographic follow-up was performed at 1 month, 3 months, 6 months and 12 months and annually thereafter. Patients with post-traumatic osteoarthritis formed the third comparison group. P ≤ 0.05 was considered statistically significant according to the analytical Student’s t-test. Results: The P < 0.05 in favor of the THA group was: surgical time, length of stay, number of the international unit of red blood cell concentrate transfusions, verticalization, quality of life and hip function, a reduction of perioperative complications and reinterventions. Conclusions: Our experience shows that the THA treatment for acetabular fractures in the elderly is to be preferred.

  19. 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

  20. Ipsilateral Traumatic Posterior Hip Dislocation, Posterior Wall and Transverse Acetabular Fracture with Trochanteric Fracture in an adult: Report of First Case

    Directory of Open Access Journals (Sweden)

    Skand Sinha

    2013-10-01

    Full Text Available Introduction: Posterior dislocation of the hip joint with associated acetabular and intertrochanteric fracture is a complex injury. Early recognition, prompt and stable reduction is needed of successful outcome. Case Report: 45 year old male patient presented with posterior dislocation of the hip with transverse fracture with posterior wall fracture of acetabulam and intertrochanteric fracture on the ipsilateral side. The complex fracture geometry was confirmed by CT scan. The patient was successfully managed by open reduction and internal fixation of intertrochanteric fracture was achieved with dynamic hip screw (DHS plate fixation followed by fixation of acetabular fracture with reconstruction plate. Conclusion: Hip dislocation combined with acetabular fracture is an uncommon injury; this article presents a unique case of posterior wall and transverse fractures of ipsilateral acetabulum with intertrochanteric fracture in a patient who sustained traumatic posterior hip dislocation. Early surgical intervention is important for satisfactory outcomes of such complex fracture-dislocation injuries. Keywords: Hip dislocation; acetabular fractures; intertrochanteric fracture; operative treatment.

  1. 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.

  2. 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

  3. Modified Stoppa Approach versus Ilioinguinal Approach for Anterior Acetabular Fractures; A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Meena, Sanjay; Sharma, Pankaj Kumar; Mittal, Samarth; Sharma, Jyoti; Chowdhury, Buddhadev

    2017-01-01

    Introduction: Modified Stoppa approach was introduced as an alternative to ilioinguinal approach for management of anterior fractures of acetabulum in order to reduce complications of the latter. However, the efficacy of either approach over other is not well established. The aim of this meta-analysis is to compare the efficacy of modified stoppa and ilioinguinal approach in the management of acetabular fractures in terms of a) quality of reduction achieved b) complication rates c) functional outcomes d) operative time e) intra-operative blood loss. Methods: Databases of PubMed, EMBASE and Cochrane registry of controlled trials were taken into consideration for studies on modified Stoppa approach versus Ilioinguinal approach group for the treatment of anterior acetabular fractures. Dichotomous variables were presented as risk ratios (RRs) /Odds Ratio (OR) with 95% confidence intervals (CIs), and continuous data was measured as mean differences, with 95% CIs. Result: Four studies involving 375 patients were included in this meta-analysis. Out of those 375 patients, 192 were managed with ilioinguinal approach and 183 were managed with modified Stoppa approach. Anatomical reduction was significantly higher in Stoppa group (p=0.052, RR=1. 19 (1.02, 1.37), p=0. 90, I2=0%). The complication rate was significantly higher in the Ilioinguinal approach as compared with the Stoppa approach (p=0.01, RR 0.63 (0.44 to 0.91), p=0.73 (I2= 0%). The operative time was significantly shorter with modified Stoppa approach (MD = -48.79 (-80.29 to -17.30), p=0.002). No significant differences were found between the two groups in terms of their functional outcomes (p=0.63, RR 0.96 (-0.80 to 1.15), p=0. 56, I2=0%) and blood loss (MD= -212.89 (-476.27 to 50.49) p=0. 06, I2=71%). Conclusion: Anterior acetabular fractures, if operated with the modified Stoppa approach were found to have better reduction and lower complication rates with less operative time, when compared to ilioinguinal

  4. The relative influence of five variables on the in vitro wear rate of uncrosslinked UHMWPE acetabular cup liners.

    Science.gov (United States)

    Lewis, Gladius; Fencl, Robert M; Carroll, Michael; Collins, Tim

    2003-05-01

    The wear factors, k(exp)(in 10(-6)mm(3)N(-1)m(-1)), of two sets of hemispherical uncrosslinked ultra-high-molecular-weight polyethylene UHMWPE acetabular cup liners, when articulated against 28-mm-diameter Co-Cr alloy femoral heads, were determined in a hip joint wear simulator. All test conditions used were the same for both sets, with the exception that in one set (comprising six liners), the bovine serum concentration in the test lubricant (P) was 25vol%, while it was 90vol% for the other set (comprising seven liners). For each liner in each set, the values of the following independent or explanatory variables were determined: the tensile toughness (U, in MJm(-3)) of the UHMWPE; the degree of crystallinity (%C) of the UHMWPE; the mean surface roughness (R(a), in microm) of the liner; and the radial clearance between the femoral head and the liner (DeltaL, in mm). All the results in both sets were combined and correlational analyses were performed between k(exp), on the one hand, and various combinations of U, %C,R(a),DeltaL, and P, on the other hand. It was found that the strongest correlations were obtained when P was included, but that %C and U are also important variables. Within the range of values of the independent variables used, the recommended relationship isk(exp)=460U(0.72)%C(-5.29)P(-0.66)(adjustedr(2)=0.858). This relationship has many potential uses, such as for screening uncrosslinked UHMWPEs that are being considered as candidates for fabricating acetabular cup liners, and for conducting studies of the sensitivity of k(exp) to a change in a value of a specified independent variable (with the values of all the other independent variables held constant). These uses, as well as the study limitations, are discussed in detail.

  5. 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.)

  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. 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.)

  8. Quality of life following total hip arthroplasty in patients with acetabular fractures, previously managed by open reduction and internal fixation

    Institute of Scientific and Technical Information of China (English)

    Prasoon Kumar; Ramesh Kumar Sen; Vishal Kumar; Ankit Dadra

    2016-01-01

    Purpose:Total hip replacement (THR) is one of the most successful and cost-effective surgical procedures and remains the treatment of choice for long-term pain relief and restoration of function for patients with diseased or damaged hips.Acetabular fractures managed either conservatively or operatively by fixation tend to present later with secondary joint changes that require THR.In this study we evaluated the functional outcome and quality of life achieved by such patients.Methods:Our study was carried out as a retrospective trial by recruiting patients who underwent THR from June 2006 to May 2012.A total of 32 patients were included with a mean age of 46.08 years ranging from (25-65) years.We evaluated the quality of life in the patients using scoring techniques of Short Musculoskeletal Functional Assessment (SMFA) and the 12-Item Short Form Health Survey (SF-12).Functional outcome was assessed using Harris Hip Score (HHS).Results:The mean HHS of the patients was 84.3 with a range from 56 to 100.The SMFA averaged 13.3.The SF-12 score averaged 49.1.The correlation of the HHS with SF-12 was positive (p =0.001) while with SMFA there was a negative correlation (p =0.001).Conclusion:From this study it is inferred that the functional outcome of THR and quality of life in patients who had acetabular fractures and were initially managed by open reduction and internal fixation is good.

  9. 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.

  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. Oxidation in ultrahigh molecular weight polyethylene and cross-linked polyethylene acetabular cups tested against roughened femoral heads in a hip joint simulator.

    Science.gov (United States)

    Taddei, Paola; Affatato, Saverio; Fagnano, Concezio; Toni, Aldo

    2006-06-01

    This study was aimed at comparing the oxidative degradation of commercial acetabular cups made of cross-linked polyethylene (XLPE) and conventional ultrahigh molecular weight polyethylene (UHMWPE). After testing against deliberately scratched CoCrMo femoral heads in a hip joint simulator, the cups, microtomed parallel to the articulating surface, were analyzed by IR spectroscopy. Due to the potential for artifacts caused by absorbed contaminants, the IR spectra were compared only after hexane extraction; actually, XLPE was found to absorb more serum than UHMWPE. The two sets of unworn acetabular cups showed different oxidation patterns with consequently different distributions of carbonyl species; unworn XLPE was characterized by lower contents of carbonyl species and hydrogen-bonded alcohols and higher contents of trans-vinylene species than unworn UHMWPE. Upon simulator testing, UHMWPE showed more significant changes in oxidation indexes and distribution of carbonyl compounds than XLPE, confirming a better wear behavior for XLPE under the adopted testing conditions.

  12. Effects of three-dimensional navigation on intraoperative management and early postoperative outcome after open reduction and internal fixation of displaced acetabular fractures

    DEFF Research Database (Denmark)

    Oberst, Michael; Hauschild, Oliver; Konstantinidis, Lukas;

    2012-01-01

    BACKGROUND: This study was conducted to evaluate whether intraoperative procedure and/or early postoperative results after open reduction and internal fixation (ORIF) of displaced acetabulum fractures are influenced by the use of a three-dimensional (3D) image intensifier in combination with a na....... In addition, the complication rate in the navigated group was significantly lower. CONCLUSION: We support the use of navigation systems and a 3D image intensifier as helpful tools during ORIF of displaced acetabular fractures. LEVEL OF EVIDENCE: Therapeutic study, level III....... acetabular fractures led to a significant increase in skin-to-skin time. Postoperative radiolographic analysis revealed an improvement in the quality of fracture reduction in the 3D navigation group. Navigation in combination with the 3D images of the ISO-C 3D limited the need for extended approaches...

  13. 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

  14. Values for bony acetabular roof angle and percentage femoral head cover in a selective ultrasound neonatal hip-screening programme: effect of age, sex and side.

    Science.gov (United States)

    Wilkinson, A Graham; Wilkinson, Sally; Elton, Robert A

    2017-02-22

    Published maturation curves for bony acetabular roof or α angle (AA) and percentage femoral head cover (FHC) with age are sparse. We aimed to determine typical values for AA and FHC in 2236 infants referred to a selective ultrasound screening programme. There was increase in the values of first measurement of AA and FHC related to the logarithm of age. Males had greater values than females (Pvalues than left (Psex, side and age-specific data.

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

    Directory of Open Access Journals (Sweden)

    Mittag Falk

    2012-09-01

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

  16. 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.

  17. 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

  18. 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.

  19. The capsular ligaments provide more hip rotational restraint than the acetabular labrum and the ligamentum teres : an experimental study.

    Science.gov (United States)

    van Arkel, R J; Amis, A A; Cobb, J P; Jeffers, J R T

    2015-04-01

    In this in vitro study of the hip joint we examined which soft tissues act as primary and secondary passive rotational restraints when the hip joint is functionally loaded. A total of nine cadaveric left hips were mounted in a testing rig that allowed the application of forces, torques and rotations in all six degrees of freedom. The hip was rotated throughout a complete range of movement (ROM) and the contributions of the iliofemoral (medial and lateral arms), pubofemoral and ischiofemoral ligaments and the ligamentum teres to rotational restraint was determined by resecting a ligament and measuring the reduced torque required to achieve the same angular position as before resection. The contribution from the acetabular labrum was also measured. Each of the capsular ligaments acted as the primary hip rotation restraint somewhere within the complete ROM, and the ligamentum teres acted as a secondary restraint in high flexion, adduction and external rotation. The iliofemoral lateral arm and the ischiofemoral ligaments were primary restraints in two-thirds of the positions tested. Appreciation of the importance of these structures in preventing excessive hip rotation and subsequent impingement/instability may be relevant for surgeons undertaking both hip joint preserving surgery and hip arthroplasty.

  20. 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.)

  1. 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

    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 anatómicos...

  2. Are component positioning and prosthesis size associated with hip resurfacing failure?

    Directory of Open Access Journals (Sweden)

    Seyler Thorsten M

    2010-10-01

    Full Text Available Abstract Background Recent studies suggest that there is a learning curve for metal-on-metal hip resurfacing. The purpose of this study was to assess whether implant positioning changed with surgeon experience and whether positioning and component sizing were associated with implant longevity. Methods We evaluated the first 361 consecutive hip resurfacings performed by a single surgeon, which had a mean follow-up of 59 months (range, 28 to 87 months. Pre and post-operative radiographs were assessed to determine the inclination of the acetabular component, as well as the sagittal and coronal femoral stem-neck angles. Changes in the precision of component placement were determined by assessing changes in the standard deviation of each measurement using variance ratio and linear regression analysis. Additionally, the cup and stem-shaft angles as well as component sizes were compared between the 31 hips that failed over the follow-up period and the surviving components to assess for any differences that might have been associated with an increased risk for failure. Results Surgeon experience was correlated with improved precision of the antero-posterior and lateral positioning of the femoral component. However, femoral and acetabular radiographic implant positioning angles were not different between the surviving hips and failures. The failures had smaller mean femoral component diameters as compared to the non-failure group (44 versus 47 millimeters. Conclusions These results suggest that there may be differences in implant positioning in early versus late learning curve procedures, but that in the absence of recognized risk factors such as intra-operative notching of the femoral neck and cup inclination in excess of 50 degrees, component positioning does not appear to be associated with failure. Nevertheless, surgeons should exercise caution in operating patients with small femoral necks, especially when they are early in the learning curve.

  3. 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

  4. 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

  5. Avaliação de método para reconstrução acetabular com uso de enxerto ósseo homólogo e implante cimentado Evaluation of a method of acetabular reconstruction using homologous bone graft and cemented implant

    Directory of Open Access Journals (Sweden)

    Milton Valdomiro Roos

    2008-09-01

    Full Text Available OBJETIVO: Avaliar clínica e radiograficamente 43 quadris em 43 pacientes submetidos a tratamento cirúrgico, para reconstrução acetabular do quadril pós-afrouxamento asséptico do implante, utilizando classificação idealizada e adotada no Serviço de Cirurgia do Quadril do Pronto Socorro de Fraturas de Passo Fundo/RS (método dos 75mm. MÉTODOS:: Foi realizado estudo retrospectivo com 88 pacientes (90 quadris submetidos a tratamento cirúrgico de reconstrução acetabular após afrouxamento asséptico do implante, entre agosto de 1994 e outubro de 2000. Desses pacientes, 43 (43 quadris preencheram todos os requisitos necessários para este trabalho. Foi considerada falha da reconstrução devido a afrouxamento, a migração do implante maior do que 5mm em qualquer direção, ou a progressão de linhas de radioluscência maior do que 2mm de largura nas zonas delimitadas por DeLee e Charnley, em associação com o critério clínico de dor. RESULTADOS: Do total de pacientes avaliados, 29 casos (67,4% foram submetidos à reconstrução acetabular com enxerto picado tipo "crouton" (1cm³; os 14 casos (32,6% restantes foram submetidos à reconstrução acetabular com enxerto em bloco. A classificação clínica pós-operatória, de acordo com os critérios de D'Aubignè et al modificados por Charnley, considerou os resultados pós-operatórios obtidos como: 83,7% satisfatórios e 16,3% insatisfatórios, com seguimento mínimo de seis anos. De acordo com os critérios estabelecidos, sete pacientes (16,3% apresentaram falhas de reconstrução devido a afrouxamento: seis com enxerto picado (20,7% das 29 enxertias com osso picado e uma com enxerto em bloco (7,1% dos 14 blocos. As falhas ocorreram, em média, aos 7,25 anos. CONCLUSÃO: Com base nos resultados obtidos, utilizando, como critério de indicação da técnica cirúrgica a adotar, a mensuração da cavidade acetabular pré-operatória (maior ou menor do que 75mm, conclui-se que o m

  6. Avaliação de método para reconstrução acetabular com uso de enxerto ósseo homólogo e implante cimentado Evaluation of a method of acetabular reconstruction using homologous bone graft and cemented implant

    Directory of Open Access Journals (Sweden)

    Milton Valdomiro Roos

    2008-10-01

    Full Text Available OBJETIVO: Avaliar clínica e radiograficamente 43 quadris em 43 pacientes submetidos a tratamento cirúrgico, para reconstrução acetabular do quadril pós-afrouxamento asséptico do implante, utilizando classificação idealizada e adotada no Serviço de Cirurgia do Quadril do Pronto Socorro de Fraturas de Passo Fundo/RS (método dos 75mm. MÉTODOS: Foi realizado estudo retrospectivo com 88 pacientes (90 quadris submetidos a tratamento cirúrgico de reconstrução acetabular após afrouxamento asséptico do implante, entre agosto de 1994 e outubro de 2000. Desses pacientes, 43 (43 quadris preencheram todos os requisitos necessários para este trabalho. Foi considerada falha da reconstrução devido a afrouxamento, a migração do implante maior do que 5mm em qualquer direção, ou a progressão de linhas de radioluscência maior do que 2mm de largura nas zonas delimitadas por DeLee e Charnley, em associação com o critério clínico de dor. RESULTADOS: Do total de pacientes avaliados, 29 casos (67,4% foram submetidos à reconstrução acetabular com enxerto picado tipo "crouton" (1cm³; os 14 casos (32,6% restantes foram submetidos à reconstrução acetabular com enxerto em bloco. A classificação clínica pós-operatória, de acordo com os critérios de D'Aubignè et al modificados por Charnley, considerou os resultados pós-operatórios obtidos como: 83,7% satisfatórios e 16,3% insatisfatórios, com seguimento mínimo de seis anos. De acordo com os critérios estabelecidos, sete pacientes (16,3% apresentaram falhas de reconstrução devido a afrouxamento: seis com enxerto picado (20,7% das 29 enxertias com osso picado e uma com enxerto em bloco (7,1% dos 14 blocos. As falhas ocorreram, em média, aos 7,25 anos. CONCLUSÃO: Com base nos resultados obtidos, utilizando, como critério de indicação da técnica cirúrgica a adotar, a mensuração da cavidade acetabular pré-operatória (maior ou menor do que 75mm, conclui-se que o m

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

    Science.gov (United States)

    Jiyang Gao; Shaojie Su; Hong Chen; Zhihua Wang

    2015-08-01

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

  8. 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.

  9. 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.

  10. Femoro-acetabular impingement: can indirect MR arthrography be considered a valid method to detect endoarticular damage? A preliminary study.

    Science.gov (United States)

    Pozzi, Grazia; Stradiotti, Paola; Parra, Cleber Garcia; Zagra, Luigi; Sironi, Sandro; Zerbi, Alberto

    2009-01-01

    To assess the effectiveness of indirect Magnetic Resonance arthrography (i-MRa) in the detection of chondral and labral lesions related to femoro-acetabular impingement (FAI) a series of 21 hip joints in 17 patients with a clinical diagnosis of FAI were examined either with standard MR imaging, i-MRa and direct-MR arthrography (d-MRa). Sensitivity and accuracy of i-MRa in detecting chondral, labral and tardive lesions were calculated and compared with standard MR. The agreement in detecting endoarticular damage between i-MRa and d-MRa and the interobserver agreement was assessed by K statistic (p<0.05). Finally the presence of trocanteric bursitis was evaluated. I-MRa showed higher values of both sensivity and accuracy than standard MR in detecting chondral damage, with an increase to 92% for the first item and 95% for the second. The same was noticed in labrum evaluation with an increase to 88% and 90% respectively. The level of agreement between i-MRa and d-MRa in detection of chondral lesions was excellent, substantial for the labral damage and absolute for early osteoarthritic changes. An excellent interobserver agreement resulted in detection of both chondral and labral damages with i-MRa. In 6 hips (28,5%) we also found the presence of peri-trochanteric soft tissue inflammation that indicated the possibility of extrarticular involvement in FAI. Indirect-MRa can be considered a valid method of assessing endoarticular damage related to FAI, in comparison to d-MRa. It should be performed instead of standard MR if d-MRa is not available.

  11. 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.)

  12. Copas de metal trabecular y aloinjertos óseos impactados en defectos acetabulares graves. Resultados a los 2-4 años. [Impacted bone allografts and trabecular metal cups in severe acetabular bone defects: 2 to 4-year results.

    Directory of Open Access Journals (Sweden)

    Martín Buttaro

    2014-06-01

    Full Text Available In­tro­duc­ción: El objetivo principal es presentar la supervivencia del componente acetabular en pacientes con defectos graves reconstruidos con copas de metal trabecular combinadas con aloinjertos óseos impactados. Como objetivo secundario, se compararon estos resultados con los previamente obtenidos por los autores en defectos de similar gravedad utilizando anillos de reconstrucción y aloinjertos óseos. Materiales­ y­ Métodos:­ Se realizaron 20 cirugías de revisión en 19 pacientes (edad promedio 65 años, controlados, de forma prospectiva, con defectos acetabulares graves tipos 3A o 3B de Paprosky, por falla mecánica o infecciosa. El puntaje funcional promedio preoperatorio fue de 6,2 puntos, según la escala de Merle D ́Aubigne. Siempre se utilizaron copas de metal trabecular y aloinjertos óseos impactados. Resultados:­ A los 30 meses de seguimiento promedio (rango 24-48 meses, la supervivencia del componente acetabular fue del 95% (IC = 75%-98%. Un paciente presentó un aflojamiento acetabular por infección profunda a las 16 semanas de la revisión y fue tratado con una artroplastia de resección. El puntaje funcional promedio, excluido el caso con aflojamiento posoperatorio, fue de 16,2 puntos. Se observó la incorporación de los aloinjertos óseos en todos los pacientes, salvo el caso con infección profunda. La comparación con nuestras series históricas reconstruidas con anillos de Kerboull o con anillos GAP arrojó resultados altamente favorables a favor de las copas de metal trabecular.  Conclusiones: Las copas de metal trabecular asociadas a aloinjertos óseos impactados ofrecen una alternativa válida en cirugía de revisión acetabular con defectos graves del capital óseo. Este método se asocia a resultados más favorables que los obtenidos antes con anillos de reconstrucción.

  13. 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

  14. 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.

  15. Transfer of metallic debris from the metal surface of an acetabular cup to artificial femoral heads by scraping: comparison between alumina and cobalt-chrome heads.

    Science.gov (United States)

    Chang, Chong Bum; Yoo, Jeong Joon; Song, Won Seok; Kim, Deug Joong; Koo, Kyung-Hoi; Kim, Hee Joong

    2008-04-01

    We aimed to investigate the transfer of metal to both ceramic (alumina) and metal (cobalt-chrome) heads that were scraped by a titanium alloy surface under different load conditions. The ceramic and metal heads for total hip arthroplasties were scraped by an acetabular metal shell under various loads using a creep tester. Microstructural changes in the scraped area were visualized with a scanning electron microscope, and chemical element changes were assessed using an energy dispersive X-ray spectrometry. Changes in the roughness of the scraped surface were evaluated by a three-dimensional surface profiling system. Metal transfer to the ceramic and metal heads began to be detectable at a 10 kg load, which could be exerted by one-handed force. The surface roughness values significantly increased with increasing test loads in both heads. When the contact force increased, scratching of the head surface occurred in addition to the transfer of metal. The results documented that metallic debris was transferred from the titanium alloy acetabular shell to both ceramic and metal heads by minor scraping. This study suggests that the greatest possible effort should be made to protect femoral heads, regardless of material, from contact with metallic surfaces during total hip arthroplasty.

  16. 髋臼骨折并发症的研究进展%The Evolution of Research on the Complication of Acetabular Fracture

    Institute of Scientific and Technical Information of China (English)

    季良全; 彭吾训

    2014-01-01

    Acetabular fracture is a kind of high-energy traumatic fracture.With the development of modern transportation and industry,it has dramatical y increased and experienced an increasingly complex trend.The anatomical structure of acetabulum is intricate and the anatomical reduction is of greater dif iculty than general.Furthermore,Acetabular fracture belongs to intra-articular fracture and often gives rise to complication,making it more intricately complex.The thesis reviews the research literatures in this filed of study.%髋臼骨折是一种高能量创伤骨折,随着现代交通及工业的发展而日渐增多,并呈现出复杂程度增加的趋势。髋臼解剖结构复杂,解剖复位难度较一般骨折大,且髋臼骨折属关节内骨折,由此导致的并发症较为复杂。本文就相关文献予以综述。

  17. 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

  18. 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.

  19. Effect of acetabular cup design on metal ion release in two designs of metal-on-metal hip resurfacing.

    Science.gov (United States)

    Cadossi, Matteo; Tedesco, Giuseppe; Savarino, Lucia; Baldini, Nicola; Mazzotti, Antonio; Greco, Michelina; Giannini, Sandro

    2014-10-01

    The purpose of this observational prospective cohort study was to evaluate the serum concentrations of cobalt (Co), chromium (Cr), and nickel (Ni) at a 2-year follow-up in patients operated on with a novel design of hip resurfacing: Romax resurfacing system (RRS). RRS is characterized by the presence of an acetabular notch which theoretically provides a wider range of motion and a reduced incidence of groin pain. The presence of radiolucencies and functional outcome, assessed using the Harris hip score (HHS) and the University of California Activity scale (UCLA), were secondary endpoints. Moreover, these results were compared with those obtained in our previous study from a similar cohort of patients implanted using the Birmingham Hip Resurfacing (BHR) system. At a 2-year follow-up, the serum levels of Co in patients operated on using the RRS were five times higher (p = 0.0002) than those found before surgery (Co, means: 1.04 and 0.20 ng/mL, respectively); similarly, Cr levels were 13 times higher (p < 0.0001) at a 2-year follow-up than before surgery (Cr, means: 1.69 and 0.13 ng/mL, respectively). Ni concentrations (0.42 and 0.78 ng/mL) were not significantly different (p = 0.16), even if they increased 86% after surgery. In the RRS patients, an inverse correlation was found between Co and Cr concentrations and length of follow-up (Co: r = -0.64, p = 0.0096; Cr: r= -0.45, p = 0.08). The serum levels of Co and Cr were not significantly different between RRS (Co: 1.04 ng/mL and Cr: 1.69 ng/mL) and BHR (Co: 1.39 ng/mL and Cr: 2.30 ng/mL) patients at 2 years (p = 0.95 and 0.26 for Co and Cr, respectively). Our results showed that RRS patients achieved an excellent clinical outcome with limited metal ion release.

  20. 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.

  1. APPLICATION OF ACETABULAR TRIDIMENSIONAL MEMORY ALLOY-FIXATION SYSTEM IN TREATMENT OF OLD ACETABULAR POSTERIOR WALL FRACTURE WITH BONE DEFECT%髋臼镍钛记忆合金三维内固定系统治疗陈旧性髋臼后壁骨折合并骨缺损

    Institute of Scientific and Technical Information of China (English)

    曹烈虎; 鲍广全; 张春才; 刘欣伟; 牛云飞; 许硕贵; 苏佳灿

    2011-01-01

    Objective To investigate the effectiveness of acetabular tridimensional memory alloy-fixation system (ATMFS) combined with autologous iliac bone in the treatment of old acetabular posterior wall fracture with bone defect. Methods Between January 2002 and February 2009, 17 patients with old acetabular posterior wall fracture and bone defect were treated, including 11 males and 6 females with an average age of 41.7 years (range, 20-60 years). The time from fracture to admission was 14-180 days (mean, 63 days). The displacement of the acetabular articular surface was more than or equal to 3 mm. According to the America Association of Orthopedic Surgeon (AAOS) acetabular fracture and defect classification standard, there were 4 cases of type I, 6 cases of type II, 5 cases of type III, and 2 cases of type IV. After the residual fracture fragments of the acetabular posterior wall and soft tissue hyperplasia were removed, the femoral head was reducted, and posterior wall defect was repaired with autologous iliac bone graft; ATMFS was used to fix acetabular posterior wall and artificial capsular ligament to reconstruct the hip so as to prevent re-dislocation of the femoral head. Results According to Matta imaging assessment standard, the results were excellent in 8 cases, good in 6 cases, fair in 2 cases, and poor in 1 case with an excellent and good rate of 82.3%. All incisions healed by first intention, and no sciatic nerve injury occurred. All patients were followed up 1-8 years (mean, 3.9 years). The mean time of fracture union was 3.6 months (range, 2-6 months). Avascular necrosis of femoral head occurred in 1 case, heterotopic ossification around the acetabulum in 1 case. According to Merle d'Aubign6-Postel scoring system evaluation, the clinical results were excellent in 9 cases, good in 6 cases, fair in 1 case, and poor in 1 case with an excellent and good rate of 88.2%. Conclusion ATMFS combined with autologous iliac bone graft and artificial ligament

  2. Learning curve of acetabular cup positioning in total hip arthroplasty using a cumulative summation test for learning curve (LC-CUSUM).

    Science.gov (United States)

    Lee, Young-Kyun; Biau, David J; Yoon, Byung-Ho; Kim, Tae-Young; Ha, Yong-Chan; Koo, Kyung-Hoi

    2014-03-01

    Despite advances in surgical techniques and instrumentation, optimal cup positioning in total hip arthroplasty (THA) is challenging with a limited accuracy. We evaluated whether a learning curve exists for the optimal cup positioning, using the LC-CUSUM test (Learning curve cumulative summation test). We evaluated the first 100 consecutive THA performed by two surgeons, who had a year of fellowship training in the same teaching hospital. A learning curve of cup positioning was plotted in each series using the LC-CUSUM score. There was no significant difference of numbers of outlier between two surgeons (P = 0.079). Both surgeons completed the learning curve of optimal cup positioning before 50 procedures, and maintained competence. A substantial learning period is necessary in the optimal positioning of an acetabular cup.

  3. Kocher-Langenback Approach for Treatment of Acetabular Fractures%Kocher-Langenback入路手术治疗髋臼骨折

    Institute of Scientific and Technical Information of China (English)

    史彤; 冯建立; 席志彬; 杨伟正

    2011-01-01

    Objective To summarize the operative method and clinical effect on acetabular fractures.Methods From January 2004 to June 2009, Kocher-Langenbeck approach were adopted in 22 cases of acetabular fracture treated operatively, including 15 cases of posterior wall fracture, 4 cases of posterior column plus posterior wall fracture, 2 cases of transverse fracture, 1 case of transverse with posterior wall fracture.Results Twenty cases were anatomically reduced, 1 case was satisfactorily reduced, 1 cases was only joint contour reduced which was unsatisfied.The excellent and good rate of clinical effect was 95.45% in those cases which had been continuously fellowed up.Complcation was observed in 1 case with incomplete traction injury of the sciatic nerve.Conclusion For fracture of the acetabulum, satisfactory reduction and clinical effect can be obtained with single approach.%目的:总结髋臼骨折的手术方法和治疗效果.方法:在26例髋臼骨折病人中,22例采用Kocher-Langenback入路治疗.结果:经12~36个月平均15个月随访,解剖复位20例,复位满意1例,不满意1例,临床效果优良率为95.45%,并发坐骨神经不全性牵拉损伤1例.结论:采用Kocher-Langenback入路手术治疗涉及髋臼后壁或后柱的骨折,可取得满意的骨折复位和临床疗效.

  4. Diagnosis and treatment for 60 cases of complex acetabular fractures at posterior wall%60例复杂髋臼后壁骨折的诊治

    Institute of Scientific and Technical Information of China (English)

    张昊; 胡亚威; 陈少初; 菅新民; 张弦; 周建华; 卢学有; 钱东阳

    2015-01-01

    目的:探讨复杂髋臼后壁骨折的诊断及手术疗效。方法自2008年1月至2013年3月,以三种体位X线平片、CT扫描、CT三维图像重建技术诊断髋臼后柱合并后壁骨折42例、横形骨折合并后壁骨折18例。采用俯卧位Kocher-Langenbeck 入路,开放复位髋臼重建接骨板和拉力螺钉固定,治疗复杂髋臼后壁骨折。结果按Matta 评定标准,骨折解剖复位率80.49%、满意复位率8.54%、不满意复位率10.97%。术后早期并发症:坐骨神经损伤1例,股神经损伤1例,髂外动脉损伤血栓形成1例,下肢深静脉血栓形成2例;晚期并发症:异位骨化3例,股骨头坏死1例,髋关节创伤性关节炎2例。结论复杂髋臼后壁骨折正确诊断主要依靠骨盆前后位、闭孔斜位、髂骨斜位X线平片检查,对于判断髋臼骨折部位、类型非常重要,CT扫描提供髋臼冠状面骨折线、骨折块等清晰图像,为复杂髋臼后壁骨折的治疗,提供选择手术入路和内固定术方案有重要意义。%Objective To analyze the diagnosis and therapeutic efficacy of the surgery for complex acetabular fractures at the posterior wall .Methods From January 2008 to March 2013, 60 cases of complex acetabular fractures were enrolled .X ray images of three positions , CT scans were performed and three dimentional image reconstruction technique of CT was used to diagnose the fractures .Among the 60 cases, 42 cases were complex acetabular fractures in posterior column and posterior wall , and 18 cases were transverse fracture combining posterior wall fracture of the acetabulum .All the patients underwent surgical treatment which applied Kocher-Langenbeck approach with prone position , open reduction and steel plates and lag screws fixation to reconstruct the acetabulum .Results According to Matta standards , the anatomical reduction rate was 80.49%, the rate of satisfied reduction was 8.54%, and the rate of

  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. 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.

  7. 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.

  8. Comparative assessment of short term outcome of cementless prosthesis versus cemented femoral stem prosthesis in hip arthroplasty for elderly intertrochanteric fracture%生物型与骨水泥型人工髋关节置换治疗高龄转子间骨折早期疗效的比较

    Institute of Scientific and Technical Information of China (English)

    闫文龙; 杨小中; 张华; 张健

    2015-01-01

    Objective To compare the short-term clinical effect of the distal fixed prosthesis ( cementless prosthesis ) with cemented femoral stem prosthesis in hip arthroplasty for elderly intertrochanteric fracture .Methods Fifty-nine cases(54 cases followed-up) of unilateral intertrochanteric fracture in senile patients from Aug .2010 to Apr.2012 were retrospectively analyzed and randomly divided into 2 groups.In them,21 cases underwent hip ar-throplasty using the distal fixed prosthesis ( cementless group ) ,and the other 33 were treated with cemented hip ar-throplasty (cement group).The difference was compared in time of hospitalization , time of operation,blood loss, adverse effect,Harris scoring and radiological results .Results The average operation time were (42.3 ±7.2) mi-nutes in cementless group and (51.5 ±8.3) minutes in cement group,with significant difference (P0.05).Conclu-sion Hip arthroplasty using cementless prosthesis for treatment of elder patients with intertrochanteric fracture can a -chieve good short-term clinical effect alike cemented prosthesis .It helps reduce operative time ,blood loss and bone cement implantation syndrome during the operation .The medium and long term effect still needs further research . And preoperative evaluation on the shape and size of medullary cavity and the severity of osteoporosis is needed .%目的:比较远端固定生物型股骨假体与骨水泥型股骨假体行人工髋关节置换治疗高龄股骨转子间骨折的早期临床疗效。方法回顾性分析2010年8月~2012年4月在我院骨科行人工髋关节置换治疗的59例单侧股骨转子间骨折高龄患者的临床资料,实际随访54例。随机分成两组:生物固定组21例,骨水泥组33例。比较两组住院时间、手术时间、术中出血量、术后3d总失血量、术后并发症、Harris评分以及放射学效果。结果生物固定组手术时间、术中出血均明显少于骨水泥组;生物固定组术中、

  9. 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.

  10. 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.

  11. Operative treatment of displaced acetabular fractures: a systematic review%移位性髋臼骨折手术治疗的系统评价

    Institute of Scientific and Technical Information of China (English)

    吴刚; 王光林; 薛建利; 杨天府; 方跃; 刘雷

    2009-01-01

    Objective To systematically review the published articles available on management for the displaced acetabular fractures. Methods MEDLINE, EMBASE, CBM and Cochrane Database were searched for the articles on management of displaced acetabular fractures in the past 40 years. Manual searches of the bibliographic sections of electronically identified papers were done to identify further papers. Meticulous data extraction and meta-analysis were performed according to preset protocol. Results Of 869 citations initially identified, 72 papers which involved a total of 6509 patients with 6549 acetabular fractures met all eligibility criteria. Reduction was anatomical or good in 87.6% of the patients, and poor in 13.0%. An incidence of iatrogenic nerve palsy was 6.0%. Deep venous thrombosis (DVT) and pulmonary embolism (PE) had an overall incidence of 3.9%. The incidence of local wound infections was 4. 2%. The heterotopic ossifi-cation (HO) was seen in 26.9% of the patients. The overall incidence of osteoarthritis (OA) was 18.0%. The score to assess the functional results, 46.6% of the patients were graded as excellent, 32.4% as good, 11.6% as fair, and 9. 5% as poor. Using the Harris Hip Score (HHS), 48.4% of the patients had an ex-cellent result, 26.9% were graded as good, 10.7% as fair, and 14.0% as poor. 85.5% of the patients with satisfactory reduction had an excellent or good functional result, while 63.7% of the patients without satis-factory reduction did. The most common cause was road traffic accident. The most common fracture types were fractures of the posterior wall and both columns as well as transverse ones associated with posterior wall. Conclusions Operative management of displaced acetabular fractures can have satisfactory functional out-comes. Reduction quality may be the major influence on functional outcome. The most common long-term complications are osteoarthritis and heterotopic ossification.%目的 采用循证医学研究方法,系统评价移位

  12. 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.)

  13. The cup safe-zone and optimum combination of the acetabular and femoral anteversions that fulfills the desired range of motion of the hip%满足日常生活活动范围的髋臼假体角度安全范围及杯颈前倾角组合

    Institute of Scientific and Technical Information of China (English)

    李永奖; 蔡春元; 张力成; 杨国敬; 周德彪; 彭茂秀; 陈文良; 赵章伟

    2011-01-01

    Objective:To investigate safe range of acetabular prosthesis angle and the optimum combination of cup and neck in the range of activities of daily living (ADL). Methods: A three-dimensional generic parametric and kinematic simulation module of THA was developed. Range of motion (ROM) of flexion 3≥110°, internal-rotation ≥30° at 90° flexion, extension ≥30° and external rotation ≥40° were defined as the normal criteria for desired ROM for activities of daily living(ADL) ,and ROM of flexion ≥120°, internal-rotation ≥45° at 90° flexion,extension ≥30° and external rotation ≥40° as the severe criteria. The range of the changes in the general head-neck ratios (GR), the femoral neck anteversion (FA), the operative antever-sion (OA) and operative inclination (OI) of the cup component were 2-2.92,0°-30° ,0°-70°, 10°-60°respectively. For the collodiaphyseal angle(CCD) of 135°,the corresponding OA related to the 01 which every 5° was calculated,and described using dots and lines in a coordinate system in which OI of acetabular cup was the horizontal ordinate and OA of acetabular cup was the vertical ordinate. All data was analyzed by SAS 6.12 software. Results:Large GR greatly increased the size of safe range and it was recommended that GR be more than 2.37 when the CCD-angle was 135° as it further increases the size of safe-zone. The size of cup safety range of the severe criteria was smaller than normal criteria. When the CCD-angle was 135°, the optimum relationship between OA of acetabular and FA of the normal criteria and the severe criteria can be estimated by the formula:Y1=-0.816x1+39.76 (R2=0.993),Y2=-0-873x2+47.04 (R2=0.999) respectively. Conclusion:Large GR greatly increases the size of safe-zone and it is recommended that GR be more than 2.37, so it extends the acceptable range of error that clinicians cannot avoid it completely. The larger range of the hip motion, the smaller size of the cup safe-zone, but can retrieve by

  14. Changes of acetabular angle at different positions after total hip arthroplasty%全髋关节置换后不同体位摄片髋臼角度的变化

    Institute of Scientific and Technical Information of China (English)

    唐智; 桂斌捷; 丁楠; 荣根祥; 高杰; 王斯晟

    2016-01-01

    BACKGROUND:During total hip arthroplasty, placement angle of acetabular prosthesis is significant for clinical curative effects. OBJECTIVE:To investigate the abduction angle and anteversion angle of acetabular prosthesis at different positions during total hip arthroplasty and related influential factors. METHODS:Thirty-five patients undergoing total hip arthroplasty were included in this study, containing 21 males and 14 females, at the age of 51-75 years old. Thesame patient at different positions underwent X-ray examination, including standing anteroposterior pelvis radiographic imaging, standing lateral radiographic imaging and supine anteroposterior pelvis radiographic imaging. Abduction angle and anteversion angle of acetabular prosthesis were measured. RESULTS AND CONCLUSION:(1) Abduction angle and anteversion angle at standing positionwere bigger than that at supine position (48.47°, 45.89°; 12.44°, 6.17°;P< 0.05). (2) The change in anteversion angle wasassociated with pelvic incidenceangleand pelvic tiltangle. The change in abduction angle was associated with pelvic obliquity. (3) The range of abduction angle (40±10)° and anteversion angle (15±10)° of acetabular prosthesis was identified as securityzone. (4) Results suggested that there were changes in acetabular abduction angle and anteversion angle between supine anteroposterior pelvis radiographic imaging and standing anteroposterior pelvis radiographic imaging after total hip arthroplasty. Acetabular angle was associated with pelvic obliquity, pelvic incidence and pelvic tilt.%背景:在人工全髋关节置换中,髋臼假体放置角度是否合适对手术临床疗效有着重要意义。目的:研究人工全髋关节置换后患者不同体位髋臼假体外展角及前倾角变化及其相关影响因素。方法:选择35例全髋关节置换后患者,其中男21例,女14例,年龄51-75岁,同一患者进行不同体位的X射线检查,分别为站立位骨盆前后位

  15. 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

  16. Analysis of Relative Motion between Femoral Head and Acetabular Cup and Advances in Computation of the Wear Factor for the Prosthetic Hip Joint

    Directory of Open Access Journals (Sweden)

    O. Calonius

    2003-01-01

    Full Text Available The amount and type of wear produced in the prosthetic hip joint depends on the type of relative motion between the femoral head and the acetabular cup. Wear particles removed from the bearing surfaces of the joint can cause adverse tissue reactions resulting in osteolysis and ultimately in loosening of the fixation of the implant. When designing a simulator for evaluation of prospective materials for artificial hip joints it is important to verify that the type of relative motion at the articulation is similar to that produced in walking, involving continually changing direction of sliding. This paper is an overview of recent research done at Helsinki University of Technology on the analysis of the relationship between relative motion and wear in the prosthetic hip joint.To analyze the relative motion, software for computing tracks, referred to as slide tracks, drawn on the counterface by marker points on the bearing surface was developed and experimentally verified. The overall relative motion of the joint was illustrated by a slide track pattern, produced by many points. The patterns resulting from walking motion and from motion produced in ten contemporary hip simulator types were compared. The slide track computations were not limited to illustrational purposes but offered a basis for computing variations of sliding distances, sliding speeds and direction of sliding during a cycle. This was done for the slide track termed the force track, drawn by the resultant contact force. In addition, the product of the instantaneous load and increment of sliding distance was numerically integrated over a cycle. This track integral of load had so far not been determined for the majority of contemporary hip simulators. The track integral can be used in determining the wear factor, making it possible to compare clinical wear rates with those produced by hip simulators. The computation of the wear factor was subsequently improved by replacing the track

  17. 髋臼发育不良的光弹性生物力学研究%Biomechanical analysis of acetabular dystplasia with photoelosticity

    Institute of Scientific and Technical Information of China (English)

    范广宇; 朱悦

    2001-01-01

    Objective To study the mechanism of osteoarthritis followed by cetabular dysplasia from the aspect of biomechanics and provide theoretical foundation for rotational acetabular osteotomy.Methods Epoxy was used to make the models of hip and femur which included four models of different shalp angle,three models of different thickness of cartilage and three models of different femoral neck body angle.Two ionalphotoelastic method was used for biomechanical analysis.Results As the sharp angle increased,the summated force endured by hip increased and the biotic stress moved to the lateral side of acetabulum;The summated force didn′t chang precisely when half of the cartilage was defective;When the cartilage didn′t exist the biotic stress was 2.5 times of that in normal condition; As the femoral neck body angle increased the biotic stress and summated force increased too,while the position on which the biotic stress concentrated didn′t change.Conclusion Cetabular dysplasia may result in osteoadhritis due to biomechanical factors. Rotational acetabular osteotomy is an effective treatment to such disease.%目的 从生物力学角度探讨髋臼发育不良继发骨关节炎的发病机理,为髋臼旋转截骨术提供依据。方法 用环氧树脂制作骨盆、股骨模型,其中包括4个不同Sharp角、3个不同软骨厚度及3个不同颈干角模型,采用二维光弹性方法进行生物力学分析。结果 随着Sharp角的增大,髋关节的合力增大,生物应力向髋臼外侧缘移动;关节软骨缺损一半时,髋关节合力未见明显变化,当关节软骨不存在时,生物应力为正常时的2.5倍;随着颈干角的增大,生物应力集中的位置没有变化,但生物应力及合力随之增大。结论 髋臼发育不良因生物力学因素可继发骨关节炎,髋臼旋转截骨术是对其有效的治疗方法。

  18. 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

  19. 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

  20. Comparison of cementless and bone-cement protheses in total hip arthroplasty for osteoporotic femoral neck fracture in elderly patients%生物型和骨水泥型股骨假体全髋关节置换术治疗老年骨质疏松性股骨颈骨折的临床效果对比

    Institute of Scientific and Technical Information of China (English)

    王华国; 叶劲; 邹仲兵; 白波

    2014-01-01

    Objective To compare the therapeutic effects of bone-cement stem and cementless stem used in the total hip arthroplasty ( THA) for treating the osteoporotic fracture of the femoral neck in the senile patients .Methods A retrospective study was carried out to analyse 100 cases of osteoporotic femoral neck fracture in the elderly patients who underwent THA in our hospital .The patients were divided into two groups by the operation methods:group A, 60 cases applied bone-cement stem in THA;group B, 40 cases applied cementless stem in THA .The hip joint function , the motion range of the joint , the imaging characteristics of the hip and posoperative pain were all compared between the two groups . Results Therewere significant differences in the clinical therapeutic effects between the two groups ( P<0.05).Conclusions The postoperative effects of the bone-cement stem is much better than the cementless stem in THA for the osteoporotic femoral neck fracture in elderly , but it may cause the risks of deep venous thromboembolism and bone cement crisis .%目的:对比老年骨质疏松股骨颈骨折使用生物型股骨假体柄与骨水泥型股骨假体柄行全髋关节置换术治疗效果。方法对本组进行老年骨质疏松股骨颈骨折100例(100髋)进行的全髋关节置换术根据手术方式分为A组(股骨假体柄骨水泥型全髋关节置换术,60髋), B组(股骨假体柄生物型全髋关节置换术,40髋)。对比两组髋关节功能、关节活动度、髋关节影像学特点及术后疼痛情况。结果老年骨质疏松股骨颈骨折行全髋关节置换术,采用生物型股骨假体柄与骨水泥型股骨假体柄的全髋关节置换术临床疗效对比差异显著( P<0.05)。结论对于老年骨质疏松股骨颈骨折行全髋关节置换术,应用骨水泥型者股骨假体柄术后近期疗效明显优于生物型,但它有诱发深静脉血栓栓塞和骨水泥危象的风险。

  1. 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.

  2. Anatomy and radiology of the back zone of acetabular posterior column%髋臼后柱后区的解剖学和影像学研究

    Institute of Scientific and Technical Information of China (English)

    赖剑强; 曹生鲁; 汪祎然; 冯凯; 王钢

    2015-01-01

    目的 探讨髋臼后柱后区的解剖学和影像学特点及其对后柱拉力螺钉固定的指导意义. 方法 收集10例(20侧)正常成年男性患者(年龄为24 ~ 67岁,平均36.1岁)的骨盆核磁共振轴位片,在坐骨棘尖平面(P1)和坐骨棘尖上5 mm平面(P2)用线1~5模拟三方位(髋臼正位、闭孔斜位和髂骨斜位)透视.线2和线3分别与后柱后骨面交于A、B点,线1与线2、线3分别交于D、C点.E为CD中点,过E作CD的垂线与后柱后面交于F点.在P1、P2平面上测量AD长度(a1、a2)和EF长度(b1、b2),以及坐骨神经前缘至后柱后骨面的距离(L1、L2).统计坐骨神经与四边形“ABCD”的位置关系. 结果 “ABCD”盲区参数:a1=(11.62±2.29) mm,b1=(9.24±1.64) mm;a2=(13.63±1.85) mm,b2=(9.01±1.94) mm.坐骨神经前缘至后柱后骨面的距离:L1 =(7.42±1.90) mm,L2=(5.83±1.93) mm.在P1平面,坐骨神经位于“盲区”内的比例为85%,其中R1区内40%,R1/R2交界区内为45%;而仅有15%位于“盲区”外.在P2平面,85%的坐骨神经位于R1区内,也仅有15%位于“盲区”外. 结论 髋臼后柱后侧面骨性结构不规则,且坐骨神经紧邻后柱骨面,是坐骨神经被拉力螺钉损伤的解剖学基础.仅依靠三方位透视不足以评估后柱拉力螺钉的位置,增加后柱切线位透视或导航有助于螺钉的准确置入.%Objective To characterize the clinical anatomy and radiology of the acetabular posterior column and to explore their significance for lag screw fixation of the acetabular posterior column.Methods This study was carried out on the axial magnetic resonance imaging of 20 right and left pelves of 10 adult males,aged from 24 to 67 years (mean,36.1 years).The parameters were measured on the plane of the ischial spine apex (P1) and the plane 5 millimeters above P1 (P2).Five lines were drawn to simulate the fluoroscopy at the anteroposterior,iliac oblique and obturator oblique views.Line 2 and line 3 intersected

  3. Progress on treatment and research of quadrilateral plate fractures of acetabular%髋臼方形区骨折的治疗及研究进展

    Institute of Scientific and Technical Information of China (English)

    彭烨; 张立海; 唐佩福

    2015-01-01

    Acetabular is an important human joint for weight bearing. Quadrilateral plate is a crucial structure of medial acetabulum with special morphology and important function. Quadrilateral plate fractures are common fracture in acetabulum. Quadrilateral plate fracture is hard to expose and reduction because it is in the medial of acetabulum. At the same time ,the bone in the quadrilateral plate is not easy to fixed for thinning bones and adjacent to the articular cavity. The operator should know well about the anatomy and choose the suitable internal fixation. After quadrilateral plate fractures ,the femur head may⁃be displace medially even break into pelvis. That make reduction and treatment always be a challenge. With different kinds of fractures,the efficacy of treatment is not the same. This paper intend to review the relation of anatomic features,approaches, internal fixations,key point of treatment and efficacy.%髋臼是人体的重要承重关节,髋臼方形区是髋臼内侧壁的重要结构,具有特殊的形态结构和重要功能。方形区骨折是髋臼骨折中常遇到的骨折,由于髋臼方形区处于骨盆内侧,所以手术中的显露及复位十分困难。同时,髋臼方形区骨质较薄较难固定,外侧有髋关节,选择合适的内固定和对相关解剖的了解十分重要。方形区骨折后,股骨头容易向内侧移位,甚至突入盆腔造成嵌顿,其复位和治疗一直是骨科中的难点。对于方形区骨折不同的治疗方法,其疗效也不一。本文就方形区的解剖学特点、手术入路选择、内固定治疗方式、治疗要点和疗效等做一综述。

  4. Safe range of artificial acetabular cup installation angle for different head-neck ratios%头颈比不同人工髋关节臼杯安置角度的安全范围

    Institute of Scientific and Technical Information of China (English)

    张振华; 孙付杰; 胡克正; 聂文波; 汪明星

    2014-01-01

    BACKGROUND:Improper angle of prosthesis placement often induces acetabular cup impact, and limits the scope of activity of artificial hip joint, and cannot meet the requirement of daily life. At present, the angle of acetabular cup instal ation remains controversial during total hip arthroplasty. Moreover, there is lack of targeted guide for the acetabular cup instal ation during hip arthroplasty with different head-neck ratios. OBJECTIVE:To explore the safe range of the artificial acetabular cup instal ation angle for different head-neck ratios. METHODS:In accordance with the calculation formula of range of internal rotation and external rotation, abduction and adduction, flexion and extension after total hip replacement, interpretation of dynamical variety law of acetabular abduction and anteversion, and deriving inequalities depending on Widmer’s standard of artificial hip joint normal activities range:(1) external rotation range was at least 40°, and internal rotation range was at least 80°. (2) Abduction range was at least 50°, and adduction range was at least 50°. (3) Anteflexion range was at least 130°, and extension range was at least 40°. The safety scope of artificial hip joint instal ation angle at different head-neck ratios was determined by solving the above three groups of inequality. RESULTS AND CONCLUSION:The safe range of the artificial acetabular cup instal ation angle for different head-neck ratios was different. To meet the normal hip joint activities, the head-neck ratios of artificial hip should be greater than 22/12. Artificial hip joint activities gradual y increase with the enlargement of head neck ratios. With enlarging the head-neck ratios, the acetabular cup instal ation safety angle scope of abduction and anteversin gradual y increases and the extreme of abduction increases gradual y, then with anteversion increasing gradual y, the abduction upper extreme of the security scope gradual y decrease and lower extreme of the

  5. 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

  6. 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.)

  7. 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...

  8. Effect of transverse acetabular ligament positioning in total hip arthroplasty%髋臼横韧带在全髋关节置换术中的定位作用

    Institute of Scientific and Technical Information of China (English)

    李建民; 李勃; 杨光; 金浪; 辛婕琛

    2016-01-01

    With the continuous advances of surgical technology and the extensive research of artificial prosthesis materials , the total hip arthroplasty technology has been widely used in the treatment of hip joint disease , while the placement of intraoperative acetabulum prosthesis imposes direct impact upon the therapeutic effects.Currently, lack of accuracy of clinical acetabulum prosthesis positioning is one of the main reasons for the total hiparthroplasty surgery complications .As a relatively fixed and common anatomic structure , transverse acetabular ligament may be used as a reliable standard reference for acetabular prosthesis imbedding in the process of the total hip arthroplasty surgery , which provides an easy-manipulating , effective and highly-repeatable alternative for the total hip arthroplasty .%随着外科手术技术和人工假体材料的不断发展,全髋关节置换术在治疗髋关节疾病方面的临床应用越来越广泛,而术中髋臼假体的安放位置是否合适对全髋关节置换术的效果可产生直接的影响。目前临床髋臼假体定位的准确度不够,这是引起全髋关节置换术术后并发症的重要原因之一。而髋臼横韧带作为一个较为固定且常见的髋臼解剖结构,在全髋关节置换手术过程中可将髋臼横韧带作为髋臼假体入位的可靠参照标准,为全髋关节置换提供一个简便、有效、重复性高的选择。

  9. 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。

  10. 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

  11. ACETABULAR RECONSTRUCTION SURGERY IN TREATMENT OF PATHOLOGICAL DISLOCATION OF HIP JOINT IN CHILDREN%髋臼重建手术在儿童髋关节病理性脱位的应用

    Institute of Scientific and Technical Information of China (English)

    蒋欣; 唐学阳; 王道喜; 陈小亮; 刘芳; 谢晓丽; 刘利君; 彭明惺

    2012-01-01

    目的 总结髋臼重建手术在儿童髋关节病理性脱位中的应用及临床疗效.方法 2006年1月-2011年1月,共收治59例(59髋)儿童髋关节病理性脱位,采用髋关节切开复位联合髋臼重建手术治疗.男22例,女37例;年龄1~15岁,平均4.9岁.化脓性髋关节炎后遗病理性脱位33例,髋关节结核26例;病程1个月~10年.髋关节半脱位9例,髋关节全脱位50例.术前Harris髋关节功能评分为43~78分,平均61分.14例髋臼指数基本正常,32例轻度增大,13例明显增大.合并髋臼破坏28例;股骨头缺血性坏死25例,股骨头部分缺失12例,股骨头完全缺失6例,股骨头颈同时缺失3例;前倾角增大25例;髋内翻畸形9例.结果 术后即刻摄X线片示所有髋关节均达中心性复位.55例切口 Ⅰ期愈合,4例切口延期愈合.53例获随访,随访时间2~5年,平均3年.随访期间无髋关节再脱位.38例髋臼指数基本正常,15例轻度增大.前倾角15~25°,平均20°;颈干角110~140°,平均125°,头颈解剖关系基本恢复正常.术后2年髋关节活动度完全恢复正常18例,屈曲及旋转轻度受限30例,纤维强直5例;Harris髋关节功能评分为62~95分,平均87分.结论 儿童髋关节病理性脱位常合并严重的髋臼及股骨头颈部骨质破坏及后遗畸形,治疗上应严格遵循个体化原则,根据患髋主要病理改变选择适当的髋臼重建术式,并结合股骨头颈重建处理,可获得满意疗效.%Objective To investigate the effectiveness of the acetabular reconstruction surgery in children pathological dislocation of the hip joint. Methods Between January 2006 and January 2011, 59 patients (59 hips) with pathological dislocation were treated by open reduction combined with acetabular reconstruction surgery. There were 22 boys and 37 girls, aged from 1 to 15 years (mean, 4.9 years). There were 9 cases of hip subluxation and 50 cases of hip joint dislocation, which were caused by suppurative

  12. 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

  13. Bilateral acetabular fracture without trauma

    OpenAIRE

    De Rosa, M. A.; G. Maccauro; D’Arienzo, M.

    1999-01-01

     In the absence of trauma fracture of the acetabulum is an extremely rare injury. We describe a 70 year old man who spontaneously developed fractures in both acetabulae due to bony insufficiency. It was successfully treated by bilateral total hip replacement.

  14. Angle of acetabular cup in total hip replacement affects the safety of joint flexion and extension%全髋关节置换中臼杯放置角度对关节屈伸活动安全性的影响

    Institute of Scientific and Technical Information of China (English)

    邵建树; 厉晓龙; 刘伟峰; 朱州; 蒋小军; 季旭彪

    2015-01-01

    BACKGROUND:Major complication after total hip replacement was instability in the form of dislocation. The probability of above complications has a great relationship with the mistakes of the angle of acetabular cup prosthesis. OBJECTIVE:To explore the influence of angle of acetabular cup in total hip replacement on the safety of joint flexion and extension. METHODS: A total of 60 patients, who underwent total hip replacement in the Wujin Hospital Affiliated to Jiangsu University from January 2012 to December 2014, were enroled in this study. Three dimensional directional monitoring device, CT scanning and image processing tools were used to preset the angle of the acetabular cup and to set abduction angle and anteversion angle. Test data were recorded and subjected to statistical analysis. RESULTS AND CONCLUSION:Acetabular cup was implanted under five different conditions: abduction angle 45°, anteversion angle 15°; abduction angle 60°, anteversion angle 15°; abduction angle 30°, anteversion angle 15°; abduction angle 45°, anteversion angle 5°; abduction angle 45°, anteversion angle 25°. According to statistics, in the patients with anteversion angle of 15°, when the acetabular cup was placed, the bigger the abduction angle, the bigger the range of abduction angle of the acetabular cup induced by pelvic tilt was. If the anteversion angle increased, the anteversion angle of the acetabular cup was reduced. With the increased pelvic tilt angle, the anteversion angle of the acetabular cup was big. Moreover, in patients with anteversion angle of 15°, the anteversion angle of the acetabular cup should keep consistent. When the abduction angle of the acetabular cup increased, the range of anteversion angle of the acetabular cup induced by pelvic tilt was diminished. These data showed that the abduction angle and anteversion angle of the acetabular cup have mutual restriction. When the acetabular cup was placed, big anteversion angle (15±10)° can wrap the

  15. Retrieval analysis of 240 metal-on-metal hip components, comparing modular total hip replacement with hip resurfacing.

    Science.gov (United States)

    Matthies, A; Underwood, R; Cann, P; Ilo, K; Nawaz, Z; Skinner, J; Hart, A J

    2011-03-01

    This study compared component wear rates and pre-revision blood metal ions levels in two groups of failed metal-on-metal hip arthroplasties: hip resurfacing and modular total hip replacement (THR). There was no significant difference in the median rate of linear wear between the groups for both acetabular (p = 0.4633) and femoral (p = 0.0872) components. There was also no significant difference in the median linear wear rates when failed hip resurfacing and modular THR hips of the same type (ASR and Birmingham hip resurfacing (BHR)) were compared. Unlike other studies of well-functioning hips, there was no significant difference in pre-revision blood metal ion levels between hip resurfacing and modular THR. Edge loading was common in both groups, but more common in the resurfacing group (67%) than in the modular group (57%). However, this was not significant (p = 0.3479). We attribute this difference to retention of the neck in resurfacing of the hip, leading to impingement-type edge loading. This was supported by visual evidence of impingement on the femur. These findings show that failed metal-on-metal hip resurfacing and modular THRs have similar component wear rates and are both associated with raised pre-revision blood levels of metal ions.

  16. 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)°

  17. 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

  18. 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.

  19. Psychological Component of Infertility

    Science.gov (United States)

    ... Home FAQs Frequently Asked Questions Quick Facts About Infertility FAQs About Infertility FAQs About the Psychological Component of Infertility FAQs About Cloning and Stem Cell Research SART's ...

  20. Extra-large uncemented acetabular components for revising total hip arthroplasty%采用超大型臼杯生物学固定行臼杯翻修术

    Institute of Scientific and Technical Information of China (English)

    孙俊英; 蒋建农; 王禹基; 董天华

    2005-01-01

    目的总结超大型臼杯无骨水泥翻修术治疗臼杯松动合并髋臼骨缺损的早期疗效.方法 11例11髋,均为首次臼杯翻修(RA)术患者.其中臼杯松动合并髋臼骨缺损(Tanzer标准)Ⅰ期者3例,Ⅱ期6例,ⅢA期2例.从全髋关节置换术(THR)至翻修术的时间最短3年,最长13年.全髋置换术的臼杯外径46~50 mm,翻修术的臼杯外径56~60 mm.假体选用AML(Depuy,USA)假体3例,Bi-Metric(Biomet,USA)2例,REF(Lima,Itali)3例,PF(UOC,Taiwan)3例.结果随访2~5年.髋关节功能(Harris标准)从翻修术前的平均30(16~54)分恢复至翻修术后的平均90(85~95)分,其中功能优9例(82%),良2例(18%),无一例需行再翻修.X线片显示:髋关节中心从术前的泪点间线近侧的平均30(17~67) mm改善至翻修术后的平均15(10~20) mm,髋关节旋转中心从泪点外侧的平均23 mm处改善至术后的33 mm,臼杯均表现骨性固定,无一例X线松动.结论对某些类型的臼杯松动骨缺损,采用超大型臼杯行无骨水泥翻修术治疗能够获得满意的临床疗效.

  1. Design of Critical Components

    Science.gov (United States)

    Hendricks, Robert C.; Zaretsky, Erwin V.

    2001-01-01

    Critical component design is based on minimizing product failures that results in loss of life. Potential catastrophic failures are reduced to secondary failures where components removed for cause or operating time in the system. Issues of liability and cost of component removal become of paramount importance. Deterministic design with factors of safety and probabilistic design address but lack the essential characteristics for the design of critical components. In deterministic design and fabrication there are heuristic rules and safety factors developed over time for large sets of structural/material components. These factors did not come without cost. Many designs failed and many rules (codes) have standing committees to oversee their proper usage and enforcement. In probabilistic design, not only are failures a given, the failures are calculated; an element of risk is assumed based on empirical failure data for large classes of component operations. Failure of a class of components can be predicted, yet one can not predict when a specific component will fail. The analogy is to the life insurance industry where very careful statistics are book-kept on classes of individuals. For a specific class, life span can be predicted within statistical limits, yet life-span of a specific element of that class can not be predicted.

  2. 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

  3. Aligning component upgrades

    Directory of Open Access Journals (Sweden)

    Roberto Di Cosmo

    2011-08-01

    Full Text Available Modern software systems, like GNU/Linux distributions or Eclipse-based development environment, are often deployed by selecting components out of large component repositories. Maintaining such software systems by performing component upgrades is a complex task, and the users need to have an expressive preferences language at their disposal to specify the kind of upgrades they are interested in. Recent research has shown that it is possible to develop solvers that handle preferences expressed as a combination of a few basic criteria used in the MISC competition, ranging from the number of new components to the freshness of the final configuration. In this work we introduce a set of new criteria that allow the users to specify their preferences for solutions with components aligned to the same upstream sources, provide an efficient encoding and report on the experimental results that prove that optimising these alignment criteria is a tractable problem in practice.

  4. Resection pseudoarthrosis for pelvic malignant tumors around acetabular%髋臼周围恶性肿瘤切除后股骨头旷置术的临床应用

    Institute of Scientific and Technical Information of China (English)

    杨正明; 陶惠民; 叶招明; 李伟栩; 杨迪生

    2011-01-01

    目的 探讨髋臼周围恶性肿瘤切除后股骨头旷置术的临床应用.方法 1997年5月至2005年6月共有25例切除后采用股骨头旷置术的髋臼周围恶性肿瘤患者得到随访,其中男性15例,女性10例;年龄16~75岁,平均42岁;骨肉瘤4例,软骨肉瘤12例,尤文肉瘤1例,原始神经外胚层瘤1例,骨髓瘤1例,恶性纤维组织细胞瘤1例,滑膜肉瘤2例,转移性肿瘤3例.根据Enneking骨盆肿瘤分区:肿瘤累及Ⅰ、Ⅱ区12例;Ⅰ、Ⅱ、Ⅲ区5例;Ⅱ、Ⅲ区4例;Ⅱ区2例;Ⅰ、Ⅱ、Ⅳ区2例.共有7例行新辅助化疗,5例行单纯术后辅助化疗,4例行术后放疗.髋臼周围切除后,采用股骨头旷置术,术后皮牵引6~8周,牵引质量2~3 kg.以后扶拐逐渐步行活动.结果 25例股骨头旷置术中6例出现手术后并发症(24.0%).随访时间3~10年,11例由于肺转移或远处转移并发肺转移死亡;2例带瘤生存;12例无瘤生存.术后5年及10年生存率分别为60%和54%.股骨头旷置术后肢体短缩在2.5~7.5 cm,平均5 cm.本组病例术后功能评价根据Enneking1993MSTS评分系统进行,平均术后功能评分是17分(12~19分).术后3个月后,患者基本能够正常坐,扶单拐跛行,能自主上下楼梯,去拐后也能跛行行走.结论 累及髋臼周围的恶性肿瘤,切除后股骨头旷置术是一种可选择的重建方式,能取得相对满意的临床效果.髋臼周围高度恶性肿瘤、软组织重建条件不佳、具有感染高危倾向者、经济条件不佳的患者,是股骨头旷置术的适应证.%Objective To discuss the resection pseudoarthrosis for pelvic malignant tumors around acetabular. Methods From May 1997 to June 2005, 25 patients with malignant tumors around acetabular were treated surgically with resection pseudoarthrosis. The series comprised 15 males and 10 females with an average age of 42 years old (range from 16 to 75 years old ) . There were 4 osteosareomas, 12chondrosarcomas, 1 Ewing's sarcoma, 1

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

    Institute of Scientific and Technical Information of China (English)

    高明杰; 陶杰; 周孜辉; 杜琳

    2015-01-01

    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 from 2005 to 2014. The keywords were“pelvis fractures, acetabulum fractures, internal fixators, materials”in Chinese and English, respectively. Articles published in authoritative journals or recently were preferred, and final y 29 articles were enrol ed in result analysis. RESULTS AND CONCLUSION:Steel plate reconstruction or screw internal fixation is often used for clinical treatment of pelvic fracture combined with acetabular fracture. Titanium plate is often chosen with similar elastic modulus to the bone and good biocompatibility. The titanium plate is pre-bended before implantation to match the bone surface of the fracture site. Absorbable screws have good histocompatibility and non-toxic side effects, which can avoid the electrolysis and corrosion of metal screws and maintain certain strength in early period of internal fixation;over time, the fracture is gradual y healed, the material strength gradual y decreases, and the material is final y degraded into water and carbon dioxide to achieve good clinical outcomes. It is difficult and high-risk for treatment of pelvic fracture combined with acetabular fractures, and active treatment and damage control are recommended as soon as possible. A reasonable treatment plan can be developed based on the type of fracture. Plate internal fixation and minimal y invasive fixation developed by the three-dimensional reconstruction techniques

  6. 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

  7. 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.

  8. 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...

  9. 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.

  10. Scientific Software Component Technology

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-02-16

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

  11. 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

  12. Application of 3D Printing Technology in the Pre-operative Evaluation of Acetabular Fractures%3D打印技术在髋臼骨折术前评估中的应用

    Institute of Scientific and Technical Information of China (English)

    王庆; 安林; 薛波; 叶鹏翰; 徐荣明

    2016-01-01

    目的:探讨3D打印技术在髋臼骨折术前评估的临床应用价值。方法整群选取2014年1月—2015年6月对该院收治的7例髋臼骨折患者进行螺旋CT扫描,将其DICOM数据输入计算机中。应用3D打印技术打印骨折模型,将骨折模型与CT 3维重建影像进行比较,制定手术方案,随后实施手术,术后进行影像学检查,观察复位效果。与既往仅根据x线及CT 3维重建影像进行术前计划者对比术后复位效果。结果7例随访X线及CT显示关节面解剖复位5例,满意复位2例。与3维重建影像相比,可以更直观观察骨折块移位情况,在模型上可以模拟骨折复位情况,使术前计划更完善。结论3D打印技术应用有助于术者对髋臼骨折的理解和术前计划的制定,提高骨折复位质量。%Objective To explore the value of three dimension 3D printing technology in the pre-operation evaluation of ac-etabular fractures. Methods Convenient selection from January 2014 to June 2015, spiral CT scan was performed in 7 pa-tients with acetabular fracture. DICOM data were imported into Mimics software. The fracture models were printed out by 3D printing technology. Models and 3D reconstructed images were compared respectively. Operative planning was worked out, and then the operation was implemented. Postoperative reduction quality was assessed on radiographs and CT scan by observers. The results were compared with the planning that made on the basis of imaging. Results The follow up CT scan showed that 5 patients achieved anatomic reduction of articular surface, and 2 patients achieved satisfactory results. Com-parative result shows that surgeons with 3D technology can observe fractures visually and operations may be stimulated on modes. So pre-operative planning can be improved. Conclusion The 3D printing technology can help surgeons to under-stand about acetabular facture, and may be a powerful tool to work out preoperative

  13. Análise do colapso segmentar da cabeça femoral nas fraturas do acetábulo tratadas cirurgicamente Analysis of the segmental impaction of femoral head following an acetabular fracture surgically managed

    Directory of Open Access Journals (Sweden)

    Rodrigo Pereira Guimarães

    2009-10-01

    Full Text Available OBJETIVO: Correlacionar a evolução radiográfica pós-operatória com as variáveis que acompanham as fraturas do acetábulo, a fim de definir o que tem valor preditivo no aparecimento do colapso segmentar da cabeça femoral. MÉTODOS: Realizada análise retrospectiva de prontuários de pacientes submetidos à cirurgia de redução aberta e fixação interna do acetábulo. Em aproximadamente 35 anos, 596 pacientes foram tratados por fratura do acetábulo; 267 foram acompanhados pelo menos por dois anos. Os demais foram excluídos por não ter sido acompanhados pelo tempo mínimo, não haver dados suficientes no prontuário ou ter sido submetidos a tratamento não operatório. O acompanhamento dos pacientes foi feito por um de três cirurgiões do grupo, utilizando a escala clínica de Merle d'Aubigné e Postel e estudos radiológicos. RESULTADOS: Somente duas variáveis estudadas, idade e qualidade da redução pós-operatória, apresentaram correlação estatisticamente significante com o colapso da cabeça femoral. CONCLUSÕES: A qualidade da redução, anatômica ou com desvio residual de até dois milímetros, apresenta evolução radiográfica satisfatória, diminuindo a probabilidade do colapso segmentar da cabeça femoral, achado que tem significância estatística.OBJECTIVE: Correlate the postoperative radiographic evaluation with variables accompanying acetabular fractures in order to determine the predictive factors for segmental impaction of femoral head. METHODS: Retrospective analysis of medial files of patients submitted to open reduction surgery with internal acetabular fixation. Within approximately 35 years, 596 patients were treated for acetabular fractures; 267 were followed up for at least two years. The others were excluded either because their follow up was shorter than the minimum time, or as a result of the lack of sufficient data reported on files, or because they had been submitted to non-surgical treatment. The

  14. Emotional Components of Pain

    Directory of Open Access Journals (Sweden)

    Carla J Hale

    1997-01-01

    Full Text Available BACKGROUND: Current definitions of pain suggest that emotion is an essential component of pain, however, the presumed relationship between emotion and pain, and the specific emotions that are involved in pain experiences have yet to be clarified.

  15. 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...

  16. 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.

  17. Develop a Model Component

    Science.gov (United States)

    Ensey, Tyler S.

    2013-01-01

    During my internship at NASA, I was a model developer for Ground Support Equipment (GSE). The purpose of a model developer is to develop and unit test model component libraries (fluid, electrical, gas, etc.). The models are designed to simulate software for GSE (Ground Special Power, Crew Access Arm, Cryo, Fire and Leak Detection System, Environmental Control System (ECS), etc. .) before they are implemented into hardware. These models support verifying local control and remote software for End-Item Software Under Test (SUT). The model simulates the physical behavior (function, state, limits and 110) of each end-item and it's dependencies as defined in the Subsystem Interface Table, Software Requirements & Design Specification (SRDS), Ground Integrated Schematic (GIS), and System Mechanical Schematic.(SMS). The software of each specific model component is simulated through MATLAB's Simulink program. The intensiv model development life cycle is a.s follows: Identify source documents; identify model scope; update schedule; preliminary design review; develop model requirements; update model.. scope; update schedule; detailed design review; create/modify library component; implement library components reference; implement subsystem components; develop a test script; run the test script; develop users guide; send model out for peer review; the model is sent out for verifictionlvalidation; if there is empirical data, a validation data package is generated; if there is not empirical data, a verification package is generated; the test results are then reviewed; and finally, the user. requests accreditation, and a statement of accreditation is prepared. Once each component model is reviewed and approved, they are intertwined together into one integrated model. This integrated model is then tested itself, through a test script and autotest, so that it can be concluded that all models work conjointly, for a single purpose. The component I was assigned, specifically, was a

  18. 全髋关节置换中C臂X射线机移位测量髋臼前倾角及外展角%C-arm X-ray machine displacement measurement of acetabular anteversion angle and abduction angle during total hip arthroplasty

    Institute of Scientific and Technical Information of China (English)

    陈军; 伏鹏; 王旭刚; 张军; 高明; 黄河; 王守刚

    2016-01-01

    BACKGROUND:In total hip arthroplasty, the accurate placement of the acetabulum is needed to guarantee the survival rate of the prosthesis and improve the prognosis. In order to ensure the accurate placement of the acetabulum, the accurate measurement of the abduction angle and the anteversion angle of the acetabulum is needed. OBJECTIVE:To investigate the application value of C-arm X-ray displacement measurement of acetabular anteversion angle and abduction angle in total hip arthroplasty. METHODS:Total y 63 cases undergoing total hip arthroplasty were divided into two groups according to their wil . Patients in the control group (n=30) were implanted with traditional acetabular prosthesis locator. Patients in the observation group (n=33) were implanted with acetabular prosthesis after C-arm X-ray displacement measurement. Acetabular anteversion angle, abduction angle and pelvic inclination were measured before, during and after arthroplasty. Acetabular anteversion angle and abduction angle were measured in both groups after arthroplasty. Pain score and hip function Harris score were recorded in both groups at different time points. RESULTS AND CONCLUSION:(1) No significant difference in acetabular anteversion angle, abduction angle and pelvic inclination was detected before, during and after arthroplasty (al P>0.05). (2) No significant difference in abduction angle was determined between the two groups after arthroplasty (P>0.05), but acetabular anteversion angle was significantly smal er in the observation group than in the control group (P0.05);②置换后2组的髋臼外展角差异无显著性意义(P>0.05),但观察组的髋臼前倾角显著小于对照组(P<0.05);③置换后7 d,观察组的目测类比评分低于对照组(P<0.05);④与置换前比较,2组置换后的Harris评分均显著提高(P<0.05);观察组置换后3,12个月的Harris评分均高于对照组(P<0.05);⑤结果提示,全髋关节置换术中利用C臂X射线机进

  19. Strontium-doped calcium polyphosphate/ultrahigh molecular weight polyethylene composites: A new class of artificial joint components with enhanced biological efficacy to aseptic loosening

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Zhipeng [College of Polymer Science and Engineering, Sichuan University, Chengdu 610065 (China); Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu 610041 (China); Huang, Bingxue; Li, Yiwen [College of Polymer Science and Engineering, Sichuan University, Chengdu 610065 (China); Tian, Meng [Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu 610041 (China); Li, Li [Department of Oncology, the 452 Hospital of Chinese PLA, Chengdu 610021 (China); Yu, Xixun, E-mail: yuxixun@163.com [College of Polymer Science and Engineering, Sichuan University, Chengdu 610065 (China)

    2016-04-01

    To enhance implant stability and prolong the service life of artificial joint component, a new approach was proposed to improve the wear resistance of artificial joint component and endow artificial joint component with the biological efficacy of resistance to aseptic loosening. Strontium calcium polyphosphate (SCPP) were interfused in ultrahigh molecular weight polyethylene (UHMWPE) by a combination of liquid nitrogen ball-milling and flat-panel curing process to prepare the SCPP/UHMWPE composites. The micro-structure, mechanical characterization, tribological characterization and bioactivities of various SCPP/UHMWPE composites were investigated. The results suggested that this method could statistically improve the wear resistance of UHMWPE resulting from a good SCPP particle dispersion. Moreover, it is also observed that the SCPP/UHMWPE composites-wear particles could promote the production of OPG by osteoblasts and decrease the production of RANKL by osteoblasts, and then increase the OPG/RANKL ratio. This indicated that the SCPP/UHMWPE composites had potential efficacy to prevent and treat aseptic loosening. Above all, the SCPP/UHMWPE composites with a suitable SCPP content would be the promising materials for fabricating artificial joint component with ability to resist aseptic loosening. - Highlights: • SCPP/UHMWPE composites could enhance biological efficacy of resistance to aseptic loosening. • SCPP would improve biological efficacy with a few sacrifice of wear resistance. • The results might provide a promising wear-resistant material for fabricating acetabular cup.

  20. 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.

  1. Adaptable component frameworks

    DEFF Research Database (Denmark)

    Katajainen, Jyrki; Simonsen, Bo

    2009-01-01

    The CPH STL is a special edition of the STL, the containers and algorithms part of the C++ standard library. The specification of the generic components of the STL is given in the C++ standard. Any implementation of the STL, e.g. the one that ships with your standard-compliant C++ compiler, shoul...... the development of component frameworks which we hope to be of benefit to persons engaged in the design and implementation of generic software libraries.......The CPH STL is a special edition of the STL, the containers and algorithms part of the C++ standard library. The specification of the generic components of the STL is given in the C++ standard. Any implementation of the STL, e.g. the one that ships with your standard-compliant C++ compiler, should...... of balanced search tree. Also, we do provide safe and compact versions of each container. To ease the maintenance of this large collection of implementations, we have developed component frameworks for the STL containers. In this paper, we describe the design and implementation of a component framework...

  2. 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

  3. 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 representi...... 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....

  4. 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.

  5. Experimental studies on acetabular cartilage of childhood rabbit after nonfunctional-posture immobilization.%非功能体位外固定对仔兔髋关节发育影响的研究

    Institute of Scientific and Technical Information of China (English)

    王道喜; 刘利君; 谢晓丽; 刘芳; 陈小亮; 蒋欣; 唐学阳

    2012-01-01

    Objective To observe the influence of small rabbits hip, including growing rule of hip, pathology changes of acetabular cartilage ,by immobilizing into nonfunctional-posture. Try to find out developping rule of the hip during treatment as DDH and the reason caused it. Methods Got 40 female NEW Zland rabbits, and random sampled into 2 groups,one was test group and the other was control group. The posterior limbs of test group were immobilized by plaster to cause treating model like DDH. Another 20 white rabbits untreated as control group. At the begaining and after 4 weeks, x-Ray was made to examed the hip status in both groups and measured the Acetabular Index(AI). In the end, the acetabulum was harvested in two groups. Firstly, checked the grossmorphology of the hip in two groups, made specimen of the hip, made paraffin slice and HE stain. Then observe pathohistologic features through microscope, compared in two groups. Adopt TUNEL stain to invest apoptosis status by counting apoptotic bodies. Use SPSS15. 0 software package to test the difference of the gross looking, acetabular index and chondrocyte apoptotic ratio between the treated group and the control group. Results The Acetabular Index got reduced in 5 treated rabbits afer 4 weeks, and nothing changed in control group. The gross acetaular sample harvested from the treated group showed a unormal shape, like ellipse shape away from the nomal spherical shape. And acetabulum became deeper and narrower. It was tested no significant different between the 2 groups through statistics testing. The cartilage upper the joint became thinner, turned grey, the head of the femur got flat, collodiaphyseal angle and back rake also had great changed in some test. After HE staining, we observed lots of fibrous tissue appearing upper cartilage, and cartilage cells arranged in disorder,lost normal column structure. With TUNEL method, it was found apoptotic cells reduced in test group compared with control group. Conclusion This

  6. 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。

  7. 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

  8. 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

  9. Component School Construction Program.

    Science.gov (United States)

    New Brunswick Dept. of Economic Growth, Fredericton.

    In 1968, the Province of New Brunswick initiated a three-phase program to provide for elementary school facilities, employing a component systems approach to their construction. This booklet describes briefly the planning and construction of these schools, and provides graphic and photographic records of the construction in progress as well as of…

  10. 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.

  11. Autonomous component carrier selection

    DEFF Research Database (Denmark)

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

    2009-01-01

    in local areas, basing our study case on LTE-Advanced. We present extensive network simulation results to demonstrate that a simple and robust interference management scheme, called autonomous component carrier selection allows each cell to select the most attractive frequency configuration; improving...

  12. Comparison of a novel porous titanium construct (Regenerex®) to a well proven porous coated tibial surface in cementless total knee arthroplasty - A prospective randomized RSA study with two-year follow-up

    DEFF Research Database (Denmark)

    Winther, Nikolaj S; Jensen, Claus L; Jensen, Claus M

    2016-01-01

    BACKGROUND: Regenerex is a novel porous titanium construct with a three-dimensional porous structure and biomechanical characteristics close to that of normal trabecular bone. The aim of this study was to compare this novel construct to a well-proven porous plasma sprayed tibial (PPS) implant aft.......04). CONCLUSION: In conclusion the Regenerex implant could prove an effective scaffold material for coating of uncemented implants but did no better than the PPS component at 24months of follow-up. ClinicalTrials.gov identifier: NCT01936415....

  13. Developing a Model Component

    Science.gov (United States)

    Fields, Christina M.

    2013-01-01

    The Spaceport Command and Control System (SCCS) Simulation Computer Software Configuration Item (CSCI) is responsible for providing simulations to support test and verification of SCCS hardware and software. The Universal Coolant Transporter System (UCTS) was a Space Shuttle Orbiter support piece of the Ground Servicing Equipment (GSE). The initial purpose of the UCTS was to provide two support services to the Space Shuttle Orbiter immediately after landing at the Shuttle Landing Facility. The UCTS is designed with the capability of servicing future space vehicles; including all Space Station Requirements necessary for the MPLM Modules. The Simulation uses GSE Models to stand in for the actual systems to support testing of SCCS systems during their development. As an intern at Kennedy Space Center (KSC), my assignment was to develop a model component for the UCTS. I was given a fluid component (dryer) to model in Simulink. I completed training for UNIX and Simulink. The dryer is a Catch All replaceable core type filter-dryer. The filter-dryer provides maximum protection for the thermostatic expansion valve and solenoid valve from dirt that may be in the system. The filter-dryer also protects the valves from freezing up. I researched fluid dynamics to understand the function of my component. The filter-dryer was modeled by determining affects it has on the pressure and velocity of the system. I used Bernoulli's Equation to calculate the pressure and velocity differential through the dryer. I created my filter-dryer model in Simulink and wrote the test script to test the component. I completed component testing and captured test data. The finalized model was sent for peer review for any improvements. I participated in Simulation meetings and was involved in the subsystem design process and team collaborations. I gained valuable work experience and insight into a career path as an engineer.

  14. Cognitive Component Analysis

    DEFF Research Database (Denmark)

    Feng, Ling

    2008-01-01

    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......-documented that unsupervised learning discovers statistical regularities. However human cognition is too complicated and not yet fully understood. Nevertheless, in our approach we represent human cognitive processes as a classification rule in supervised learning. Thus we have devised a testable protocol to test...

  15. 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...

  16. Compressive Principal Component Pursuit

    CERN Document Server

    Wright, John; Min, Kerui; Ma, Yi

    2012-01-01

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

  17. 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...

  18. 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...... in a Matlab toolbox, is demonstrated for non-negative decompositions and compared with non-negative matrix factorization....

  19. 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...

  20. Inkjet deposited circuit components

    Science.gov (United States)

    Bidoki, S. M.; Nouri, J.; Heidari, A. A.

    2010-05-01

    All-printed electronics as a means of achieving ultra-low-cost electronic circuits has attracted great interest in recent years. Inkjet printing is one of the most promising techniques by which the circuit components can be ultimately drawn (i.e. printed) onto the substrate in one step. Here, the inkjet printing technique was used to chemically deposit silver nanoparticles (10-200 nm) simply by ejection of silver nitrate and reducing solutions onto different substrates such as paper, PET plastic film and textile fabrics. The silver patterns were tested for their functionality to work as circuit components like conductor, resistor, capacitor and inductor. Different levels of conductivity were achieved simply by changing the printing sequence, inks ratio and concentration. The highest level of conductivity achieved by an office thermal inkjet printer (300 dpi) was 5.54 × 105 S m-1 on paper. Inkjet deposited capacitors could exhibit a capacitance of more than 1.5 nF (parallel plate 45 × 45 mm2) and induction coils displayed an inductance of around 400 µH (planar coil 10 cm in diameter). Comparison of electronic performance of inkjet deposited components to the performance of conventionally etched items makes the technique highly promising for fabricating different printed electronic devices.

  1. Optimized Kernel Entropy Components.

    Science.gov (United States)

    Izquierdo-Verdiguier, Emma; Laparra, Valero; Jenssen, Robert; Gomez-Chova, Luis; Camps-Valls, Gustau

    2016-02-25

    This brief addresses two main issues of the standard kernel entropy component analysis (KECA) algorithm: the optimization of the kernel decomposition and the optimization of the Gaussian kernel parameter. KECA roughly reduces to a sorting of the importance of kernel eigenvectors by entropy instead of variance, as in the kernel principal components analysis. In this brief, we propose an extension of the KECA method, named optimized KECA (OKECA), that directly extracts the optimal features retaining most of the data entropy by means of compacting the information in very few features (often in just one or two). The proposed method produces features which have higher expressive power. In particular, it is based on the independent component analysis framework, and introduces an extra rotation to the eigen decomposition, which is optimized via gradient-ascent search. This maximum entropy preservation suggests that OKECA features are more efficient than KECA features for density estimation. In addition, a critical issue in both the methods is the selection of the kernel parameter, since it critically affects the resulting performance. Here, we analyze the most common kernel length-scale selection criteria. The results of both the methods are illustrated in different synthetic and real problems. Results show that OKECA returns projections with more expressive power than KECA, the most successful rule for estimating the kernel parameter is based on maximum likelihood, and OKECA is more robust to the selection of the length-scale parameter in kernel density estimation.

  2. 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.

  3. 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.

  4. 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

  5. Analysis Components Investigation Report

    Science.gov (United States)

    2014-10-01

    value is t ds each te rms presen t, and !()*+) PREVIOUS WRI open sour a training , tagged -1 t or... measure tion and Analys 2 is Component THIS DOCU The mis pro inte cou For sele con The use as solu ran .3 Prot In t be A G and wh and sec Wh info Thi...ASSIFIED December 2 LOSED TO ANY P d to specif c. The valu , the user c keywords p as relevan ument’s me system cou the docum iterion and/ e

  6. Recursive principal components analysis.

    Science.gov (United States)

    Voegtlin, Thomas

    2005-10-01

    A recurrent linear network can be trained with Oja's constrained Hebbian learning rule. As a result, the network learns to represent the temporal context associated to its input sequence. The operation performed by the network is a generalization of Principal Components Analysis (PCA) to time-series, called Recursive PCA. The representations learned by the network are adapted to the temporal statistics of the input. Moreover, sequences stored in the network may be retrieved explicitly, in the reverse order of presentation, thus providing a straight-forward neural implementation of a logical stack.

  7. 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.

  8. 生物型陶瓷人工双极股骨头假体的5年临床和放射学影像随访分析%Five-year clinical and radiographic follow-up of hip hemiarthroplasty with cementless porous-coated anatomic femoral component and ceramic bipolar femoral head prosthesis

    Institute of Scientific and Technical Information of China (English)

    周军杰; 曹成福; 庞金辉; 陈贤奇; 高文武

    2013-01-01

    目的 评估应用生物型陶瓷人工双极股骨头假体置换治疗老年新鲜股骨颈骨折的5年临床和放射学影像随访疗效.方法 回顾性分析2005年4月至2007年4月,87例接受生物型陶瓷人工双极股骨头置换治疗的老年股骨颈骨折患者,男39例,女48例;年龄72~96岁,平均(83.4±4.12)岁.股骨颈骨折的分型按Garden分型:Ⅲ型32例,Ⅳ型55例.术前均经常规双能X线吸收测量法(DXA)检测脊柱及髋部骨密度(BMD)筛选,全部采用Biomet生物型Bi-Metric系列股骨假体和陶瓷双极股骨头假体.患者分别在手术后1.5、3、6、12个月及之后每年随访一次,根据临床髋关节活动度和Harris评价标准,放射学影像根据AAOS评价指标:髋臼磨损情况,陶瓷组件碎裂情况,假体周围骨溶解及溶骨性病变情况,股骨近端骨生长情况,股骨距重塑,股骨假体远端底座形成情况等.结果 实际83例患者完成终末随访,随访时间61~82个月,平均(72.4±6.57)个月.髋关节活动范围在终末随访时为:屈曲平均(83.5 °± 9.14°),后伸平均(25.2°±5.62°),外展平均(41.5°±5.21°).Harris评分从术前平均(11.5±4.0)分,提高到终末随访时平均(89.1±2.1)分,手术前后有统计学差异(t=27.18,P<0.01);其中优31例,良40例,可10例,差2例,优良率为85.54%(71/83).5例(6.02%)患者出现腹股沟区和大腿前侧疼痛,2例(2.41%)患者在手术后3~5年间由于股骨假体出现松动而进行股骨假体翻修.放射影像学随访观察无髋臼严重磨损,无陶瓷组件碎裂,无股骨假体周围骨溶解,无股骨假体松动,股骨近端骨生长情况良好,有24例(28.92%)患者发生股骨假体远端轻度底座形成.结论 应用生物型陶瓷人工双极股骨头假体置换治疗老年新鲜股骨颈骨折获得较好的5年临床和放射学影像随访效果.

  9. 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

  10. 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

  11. 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.

  12. Advanced Power Electronics Components

    Science.gov (United States)

    Schwarze, Gene E.

    2004-01-01

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

  13. 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.

  14. 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.

  15. Prognostics for Microgrid Components

    Science.gov (United States)

    Saxena, Abhinav

    2012-01-01

    Prognostics is the science of predicting future performance and potential failures based on targeted condition monitoring. Moving away from the traditional reliability centric view, prognostics aims at detecting and quantifying the time to impending failures. This advance warning provides the opportunity to take actions that can preserve uptime, reduce cost of damage, or extend the life of the component. The talk will focus on the concepts and basics of prognostics from the viewpoint of condition-based systems health management. Differences with other techniques used in systems health management and philosophies of prognostics used in other domains will be shown. Examples relevant to micro grid systems and subsystems will be used to illustrate various types of prediction scenarios and the resources it take to set up a desired prognostic system. Specifically, the implementation results for power storage and power semiconductor components will demonstrate specific solution approaches of prognostics. The role of constituent elements of prognostics, such as model, prediction algorithms, failure threshold, run-to-failure data, requirements and specifications, and post-prognostic reasoning will be explained. A discussion on performance evaluation and performance metrics will conclude the technical discussion followed by general comments on open research problems and challenges in prognostics.

  16. 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

  17. 腹股沟韧带下入路治疗髋臼前柱合并前壁骨折%Modified subinguinal approach for treatment of acetabular anterior column and wall fractures

    Institute of Scientific and Technical Information of China (English)

    高峰; 秦晓东; 李翔; 方永祥; 杨峰

    2016-01-01

    Objective To discuss the efficacy of the modified subinguinal approach for the treatment of acetabular anterior column and wall fractures.Methods A clinical retrospective study was performed of the 5 patients who had been treated at our department from January 2011 to April 2015 for acetabular anterior column and wall fractures and conformed to follow-ups.They were 3 males and 2 females,aged from 19 to 45 years (mean,35.6 years).The duration from injury to surgery averaged 7.6 days (range,from 4 to 10 days).The subinguinal ligament approach was adopted in the 5 cases,through which the inguinal ligament was preserved intact after sharp dissection of its insertion at the anterior superior iliac spine and medial-upper advancement,the advantage of expanded exposure of "the first window" by the Farid sub-ilioinguinal approach was retained,and additional lesions due to iliac osteotomy were avoided.The operation time,intraoperative bleeding,postoperative reduction and time for fracture union were documented.Merle d' Aubigne and Postel scoring system was used to assess the hip joint function of the affected limb at the final follow-ups.Results The operation time ranged from 110 to 150 minutes (mean,125 minutes);the intraoperative bleeding ranged from 415 to 550 mL (mean,450.2 mL).By the Matta's criteria,the postoperative reduction was rated as excellent in 4 cases and good in one.The 5 patients were followed up for an average of 32.4 months (range,from 6 to 43 months).Their fractures united clinically after an average of 4.6 months (range,from 3 to 6 months).The hip joint function was rated as excellent in 2 and good in 3 by the Merle d' Aubigne and Postel scoring system at the final follow-ups.Follow-ups observed no serious complications like inguinal hernia,internal fixation failure,myositis ossificans,or avascular necrosis of the femoral head.Conclusions As the modified subinguinal approach can provide a broad surgical exposure,lead to minimal injury to the inguinal

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Component Composition Using Feature Models

    DEFF Research Database (Denmark)

    Eichberg, Michael; Klose, Karl; Mitschke, Ralf;

    2010-01-01

    In general, components provide and require services and two components are bound if the first component provides a service required by the second component. However, certain variability in services - w.r.t. how and which functionality is provided or required - cannot be described using standard...... interface description languages. If this variability is relevant when selecting a matching component then human interaction is required to decide which components can be bound. We propose to use feature models for making this variability explicit and (re-)enabling automatic component binding. In our...... approach, feature models are one part of service specifications. This enables to declaratively specify which service variant is provided by a component. By referring to a service's variation points, a component that requires a specific service can list the requirements on the desired variant. Using...

  3. Local Component Analysis

    CERN Document Server

    Roux, Nicolas Le

    2011-01-01

    Kernel density estimation, a.k.a. Parzen windows, is a popular density estimation method, which can be used for outlier detection or clustering. With multivariate data, its performance is heavily reliant on the metric used within the kernel. Most earlier work has focused on learning only the bandwidth of the kernel (i.e., a scalar multiplicative factor). In this paper, we propose to learn a full Euclidean metric through an expectation-minimization (EM) procedure, which can be seen as an unsupervised counterpart to neighbourhood component analysis (NCA). In order to avoid overfitting with a fully nonparametric density estimator in high dimensions, we also consider a semi-parametric Gaussian-Parzen density model, where some of the variables are modelled through a jointly Gaussian density, while others are modelled through Parzen windows. For these two models, EM leads to simple closed-form updates based on matrix inversions and eigenvalue decompositions. We show empirically that our method leads to density esti...

  4. 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.

  5. Impaction bone graft and cementless total hip arthroplasty for treating ankylosing spondylitis in 17 patients%嵌压植骨结合非骨水泥型全髋关节置换治疗强直性脊柱炎17例

    Institute of Scientific and Technical Information of China (English)

    常增林; 李锋

    2009-01-01

    1996-03/2003-03纳入强直性脊杜炎合并股骨侧严重骨质疏松的髋关节病变患者17例(24髋),采用自体骨嵌压植骨结合非骨水泥型全髋关节置换治疗.手术时年龄20~52岁,平均35岁;采用Harris评分方法及X射线片观察进行临床疗效评定.17例患者24髋均获得完整随访,随访时间36~120个月,平均87个月.Harris评分从置换前平均34分提高到置换后平均86.4分,优良率87.5%.X射线片见股骨假体与股骨近段紧密压配;无假体感染及脱位.1髋出现5 mm的假体下沉,发生于置换后1年内,经过5年以上随访观察,假体未进一步下沉,并与骨质接触良好,目前无松动表现.提示骨质皱对非骨水泥假体置换的疗效影响较大,采用自体骨嵌压植骨技术进行骨质重建,可为强直性脊梓炎合并严重骨质疏松患者全髋关节置换提供了一种良好的解决方法,临床效果满意.%A total of 17 hip joint lesion patients (24 hips) combined with ankylosing spondylitis and severe osteoporosis from March 1996 to March 2003.They.received autologous impaction bone graft and cementless total hip replacement.They were 20-52 years old,averagely 35 years.Harris score and X-ray method were used to evaluate clinical outcomes.A total of 17 patients (24 hips) were followed up for 36-120 months,averagely 87 months.Harris score increased from averagely 34 points (preoperation) to averagely 86.4 points (postoperation),resulting in an excellent and good rate of 87.5%.Radiograph showed that femoral prosthesis was closely fixed to proximal segment of the femur,without prosthetic infection or dislocation.One hip suffered from 5-mm prosthetic subsidence within 1 year following replacement,and no further subsidence following over 5-year follow up.The prosthesis showed good contact to sclerotin,without loose.It is suggested that bone mass has great effects on cementtess prosthetic replacement.Autologous impaction bone graft for bone remodeling provides

  6. 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

  7. 多层螺旋CT多模式重组在复杂髋臼骨折术前检查中的应用%The preoperative application of multi slice CT with three-dimensional reconstruction in complex acetabular fractures

    Institute of Scientific and Technical Information of China (English)

    陈木养; 黄伟坚; 余洪希; 王东

    2016-01-01

    Objective To evaluate the value of volume scanning method, multiplanar reconstruction (MPR), surface shaded display (SSD), and volume reconstruction (VR) techniques in the preoperative examination of complex acetabular fractures. Methods Fifty-eight cases with ancetabular fractures were all accepted CT volume scanning , and MPR were done in all cases. In addition, case-control analysis were done with conventional acetabular CT imagings. Results Coronal plane of MPR, surface shaded display (SSD) combined with VR imaging, could display the acetabular fractures clearly, in accordance with the operations, and its diagnostic accuracy was significantly higher than conventional CT scan. The two sets of data had significances difference (P<0.05) in displaying fracture type, the length of the fracture lines, the shapes and direction of the fracture, the sizes of fracture pieces, the spatial location, the degree of fracture displacement and the joint dislocation classification. Conclusion Multi slice CT (MSCT) volume scanning, MPR, SSD and VR techniques have good display abilities of acetabular fractures , their performance are close to the pathological anatomy. They are considered to be the ideal imaging methods to know about the complex acetabular fractures and its microscopic structures.%目的:利用多层螺旋CT的容积扫描方法和多平面重建(MPR)、表面遮盖法(SSD)及容积再现(VR)技术,评价其在复杂性髋臼骨折术前检查中的应用价值。方法选取58例患者的损伤髋臼进行多层螺旋CT容积扫描,所得原始数据做数字化三维重组处理,并与常规髋臼CT平扫图像进行对照分析。结果 MPR冠状面、SSD重建结合VR成像,能清晰显示58例髋臼骨折情况,与手术相符,诊断正确率明显高于常规CT平扫。在显示骨折分型、骨折线的长短、形态、走向,骨折片大小、空间位置以及骨折移位程度和关节脱位分类征象方面,2组

  8. Towards Prognostics for Electronics Components

    Data.gov (United States)

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

  9. Cooling system for electronic components

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-05-17

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

  10. Cooling system for electronic components

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. 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.

  12. Formalization in Component Based Development

    DEFF Research Database (Denmark)

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

    2006-01-01

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

  13. 3D打印技术在复杂髋臼骨折治疗中的应用%3D printing used in treatment of complex acetabular fractures

    Institute of Scientific and Technical Information of China (English)

    张国明; 周东生; 贺宇; 王伯珉; 李连欣; 李庆虎; 余也

    2016-01-01

    Objective To evaluate 3D printing used in the treatment of complex acetabular fractures.Methods Between January 2009 and December 2013,121 patients with complex acetabular fracture were treated at our department.3D printing was used in surgical planning in 53 of them,including 36 males and 17 females with an average age of 41.2 ± 10.4 years (3D group).The other 68 patients received conventional surgery without use of 3D printing,including 42 males and 26 females with an average age of 42.6 ± 8.9 years (conventional group).By the Judet-Letournel classification system,there were respectively 7 and 9 T-type fractures,4 and 6 posterior column with posterior wall fractures,21 and 28 transverse and posterior wall fractures,5 and 6 anterior with the second half transverse fractures,and 16 and 19 double column fractures.Surgical time,blood loss,transfusion,fluoroscopy times and complications were recorded in the 2 groups.At the final follow-ups,the clinical results were assessed by Merle D'Aubigné & Postel scoring and the radiographic results were assessed by Matta records.The 2 groups were similar in preoperative demographic data (P > 0.05).Results In the 3D and conventional groups,respectively,surgical time was 3.5 ±O.9 hours versus 4.5 ± 1.1 hours,blood loss was 1,200.2 ±232.8 mL versus 1,550.4 ±211.6 mL,transfusion was 8.9 ± 3.8 U versus 12.3 ± 2.9 U,and fluoroscopy times were 8.7 ± 2.1 versus 11.9 ± 2.4.The differences between the 2 groups were statistically significant (P < 0.05).The 3D and conventional groups were respectively followed up for 20.3 and 37.8 months on average.All the acetabular fractures healed.The time from surgery to full-weight-bearing walking averaged 3.5 months.Iatrogenic ischiadic nerve injury occurred in 5 and 7 cases and superficial infection in 3 and 5 cases in the 3D and conventional groups,respectively.No iatrogenic vascular injury,nonunion,or implant failure occurred in the 2 groups.By the Merle D' Aubigné & Postel records

  14. Surgical treatment of unstable pelvic fractures combined with acetabular fractures%不稳定骨盆骨折合并髋臼骨折手术治疗的疗效分析

    Institute of Scientific and Technical Information of China (English)

    王陶; 王军; 李宗原; 刘刚

    2015-01-01

    目的:探讨不稳定骨盆骨折合并髋臼骨折的治疗策略及临床疗效。方法:2007年1月至2013年6月收治32例不稳定骨盆骨折合并髋臼骨折患者,男18例,女14例;年龄18~62岁,平均38岁。Tile骨盆骨折分型:B1型11例,B2.1型8例,B2.2型7例,C1.1型3例,C1.2型2例,C3型1例。Judet-Letournel髋臼骨折分型:前柱骨折1例,横形骨折8例,横形加后壁骨折6例,“T”形骨折1例,前柱加后半横形骨折5例,双柱骨折11例。早期处理其他合并6.5 h,平均3 h;术中失血450~3200 ml,平均1200 ml。有2例肥胖患者切口发生脂肪液化,换药后愈合,无切口感染病例。1例失访,31例获得随访,随访时间6~42个月,平均23个月。骨盆骨折愈合时间8~18周,平均10.6周。按照Matta和Tornetta的评分标准评价复位情况,优15例,良14例,可1例,差1例。Majeed功能评分为83.65±7.67,优15例,良12例,可4例。髋臼骨折愈合时间8~16周,平均10.2周。采用Matta评定标准评估术后复位质量,优15例,良12例,差4例。按Brooker标准评价异位骨化,Ⅰ度4例,Ⅱ度1例。无股骨头坏死及骨折不愈合发生,5例并有神经损伤者4~6个月后均完全恢复。结论:不稳定骨盆骨折合并髋臼骨折患者早期病情危重,运用损伤控制理念及时抢救生命为主。后期把握手术时机,治疗时髋臼骨折尽量解剖复位,骨盆骨折以重建稳定为主,手术复位顺序先固定骨盆后环,根据病情选择合适的手术入路及固定方式。%Objective:To discuss the treatment strategy of acetabular fractures and unstable pelvic fracture of the hip and to evaluate its outcome. Methods:Retrospective analysis of clinical data in 32 patients with unstable pelvic fracture and acetabular fractures from January 2007 to June 2013 were collected. There were 18 males and 14 females aged from 18 to 62 years old(means 38

  15. 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。

  16. Component-specific modeling. [jet engine hot section components

    Science.gov (United States)

    Mcknight, R. L.; Maffeo, R. J.; Tipton, M. T.; Weber, G.

    1992-01-01

    Accomplishments are described for a 3 year program to develop methodology for component-specific modeling of aircraft hot section components (turbine blades, turbine vanes, and burner liners). These accomplishments include: (1) engine thermodynamic and mission models, (2) geometry model generators, (3) remeshing, (4) specialty three-dimensional inelastic structural analysis, (5) computationally efficient solvers, (6) adaptive solution strategies, (7) engine performance parameters/component response variables decomposition and synthesis, (8) integrated software architecture and development, and (9) validation cases for software developed.

  17. Long-term results of femoral revision with the Wagner Self-Locking stem.

    Science.gov (United States)

    Regis, Dario; Sandri, Andrea; Bonetti, Ingrid

    2013-09-01

    Femoral revision total hip arthroplasty may be a complex procedure due to extensive periprosthetic bone loss. Fluted, tapered stems provide secure axial and rotational stability in the distal femur. We retrospectively evaluated the long-term outcome of the cementless Wagner Self-Locking prosthesis (Sulzer Orthopedics Ltd, Winterthur, Switzerland). From 1992 to 1998, 68 consecutive femoral revisions were performed in 66 patients using the Wagner tapered stem. Twenty-five patients deceased for unrelated causes without additional surgery. The studied group consisted of 41 hips in 41 patients, 12 males and 29 females, aged from 29 to 80 years (mean 61 years). Thirty-five hips (85.4%) included severe deficiency of bone stock. A transfemoral approach was carried out in 32 cases (78%). Bone grafting was never supplemented. Average follow-up was 13.9 years (range 10.4 to 15.8 years). Clinical evaluation was performed using Harris Hip Score (HHS). Osseointegration of the stem and progression of periprosthetic bone remodelling were assessed radiographically. Five stems required rerevision because of deep infection (2), progressive subsidence (2) complicated by hip instability and head-neck disassembly, and old dislocation following acetabular component failure (1). Four hips (9.7%) dislocated, and 8 stems (19.5%) subsided significantly. Average HHS improved from 33 points preoperatively to 75 points at the latest follow-up examination (p risk complications (dislocation, subsidence) should be minimized by the development of modular stems.

  18. 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.

  19. 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

  20. 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

  1. SBA Network Components & Software Inventory

    Data.gov (United States)

    Small Business Administration — SBA’s Network Components & Software Inventory contains a complete inventory of all devices connected to SBA’s network including workstations, servers, routers,...

  2. 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.

  3. Semantic Annotation of Computational Components

    Science.gov (United States)

    Vanderbilt, Peter; Mehrotra, Piyush

    2004-01-01

    This paper describes a methodology to specify machine-processable semantic descriptions of computational components to enable them to be shared and reused. A particular focus of this scheme is to enable automatic compositon of such components into simple work-flows.

  4. Components of Successful Magnet Schools.

    Science.gov (United States)

    Bryant, Faye B.

    This paper identifies and discusses components of successful magnet programs. It is based on a review of existing research literature and information gathered directly from school districts. First, the paper discusses separately the following elements, which are considered "core components": (1) leadership; (2) organizational structure; (3)…

  5. 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

  6. 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

  7. 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 iden......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...... 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....

  8. 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.

  9. Experimental biomechanical analysis of standing position in both-column acetabular fractures fixed by anterior reconstruction plate combinated with trans-plate quadrilateral screws%前路钛板加方形区螺钉治疗髋臼双柱骨折的站立位力学分析

    Institute of Scientific and Technical Information of China (English)

    蔡贤华; 吴咏德; 刘曦明; 张红喜

    2013-01-01

    [目的]探讨前路特殊塑形钛板加方形区螺钉治疗髋臼双柱骨折早期站立的可能性.[方法]选取成年防腐保湿处理的全骨盆标本6具,保留韧带及髋关节囊,制作单侧髋臼高位双柱骨折模型,随机先后采用前路特殊塑形钛板加方形区螺钉(B组)及常规塑形钛板加1/3管型钛板(C组)内固定,固定标本于ZWICKZ100电子万能材料试验机上,模拟站立位以400~700 N垂直加载,分别测定完整骨盆(A组)、B组及C组后柱内壁横向位移、髋臼顶纵向位移,并计算刚度.[结果]随着载荷增加,各位移值呈逐渐增加的线性关系,且A组<B组<C组;在生理负荷600N载荷下,横向与纵向位移值均为C组>B组>A组、刚度为C组>B组>A组,C组与B组、A组与C组间差异明显(P<0.05),B组与A组差异无显著意义(P>0.05).[结论]站立位下,前路特殊塑形钛板加方形区螺钉较常规塑形钛板加1/3管型钛板内固定即刻力学性能更为可靠,稳定性与完整骨盆接近,这表明早期站立并不影响前路特殊塑形钛板加方形区螺钉内固定的稳定性.%[ Objective] To explore the standing possibility in the early after both - column acetabular fracture fixed by anterior specially - shaped reconstruction plate combinated with trans - plate quadrilateral screws on cadaver. [ Method] Six Chinese adult wetly pelvic specimens with their ligament and joint capsule of hip joint preserved with antisepsis were made into the model with high both-column acetabular fracture on one side. The fractures were fixed randomly by anterior specially-shaped titanium plate with quadrilateral screws( group B) or conventionally-shaped reconstruction titanium plate with 1/3 tubular titanium plate (group C). To imitate the static standing position of the patient,the specimen fixed on ZWICK-Z100 electronic universal material testing machine received the vertical loading from 400 N to 700 N to measure the transverse displacement of

  10. Vacuum Brazing of Accelerator Components

    Science.gov (United States)

    Singh, Rajvir; Pant, K. K.; Lal, Shankar; Yadav, D. P.; Garg, S. R.; Raghuvanshi, V. K.; Mundra, G.

    2012-11-01

    Commonly used materials for accelerator components are those which are vacuum compatible and thermally conductive. Stainless steel, aluminum and copper are common among them. Stainless steel is a poor heat conductor and not very common in use where good thermal conductivity is required. Aluminum and copper and their alloys meet the above requirements and are frequently used for the above purpose. The accelerator components made of aluminum and its alloys using welding process have become a common practice now a days. It is mandatory to use copper and its other grades in RF devices required for accelerators. Beam line and Front End components of the accelerators are fabricated from stainless steel and OFHC copper. Fabrication of components made of copper using welding process is very difficult and in most of the cases it is impossible. Fabrication and joining in such cases is possible using brazing process especially under vacuum and inert gas atmosphere. Several accelerator components have been vacuum brazed for Indus projects at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore using vacuum brazing facility available at RRCAT, Indore. This paper presents details regarding development of the above mentioned high value and strategic components/assemblies. It will include basics required for vacuum brazing, details of vacuum brazing facility, joint design, fixturing of the jobs, selection of filler alloys, optimization of brazing parameters so as to obtain high quality brazed joints, brief description of vacuum brazed accelerator components etc.

  11. 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.

  12. Comparison of the Therapeutic Effect of Modified Stoppa Approach and Rectus Lateral Approach for the Treatment of Acetabular Fracture Combined with Ipsilateral Pelvic Fracture%改良stoppa切口入路与腹直肌外侧入路治疗合并骨盆骨折的髋臼骨折的疗效比较

    Institute of Scientific and Technical Information of China (English)

    邵晏清; 熊然; 张潇; 杨晓东; 夏广; 樊仕才

    2016-01-01

    Objective To compare the curative effect of the modified stoppa incision and rectus lateral incision approach in treatment of acetabular fracture combined with ipsilateral pelvic fracture .Methods A retrospective analysis of the clinical data of 29 patients with acetabular fracture combined with ipsilateral pel-vic fracture treated in Southern Medical University Third Hospital from Mar .2011 to Apr.2014 was done, including 18 cases of lateral rectus incision approach(group A),11 cases of modified stoppa incision ap-proach(group B).The surgical exposure time,intraoperative blood loss,the fracture recovery and the postop-erative complications of the two groups were compared.Results Surgical exposure time in group A,B were (17.4 ±3.6) min,(16.9 ±4.4) min respectively; postoperative hip joint function score were (16.8 ± 2.7),(17.3 ±2.2) respectively,the differences had no statistical significance(P >0.05);intraoperative blood loss of group A was less than that in group B[(627 ±26) mL vs (742 ±40) mL],the difference was statistically significant(P0.05);A组术中出血量少于B组[(627 ±26) mL比(742 ±40) mL],差异有统计学意义(P0.05 ). 结论 经腹直肌外侧切口入路能充分显露髋臼前柱和四方体,能正视下复位并固定髋臼骨折,且手术显露简单、损伤小,手术并发症少,是治疗髋臼前方骨折尤其是累及四方体骨折的理想手术入路.

  13. 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

  14. Component Based Electronic Voting Systems

    Science.gov (United States)

    Lundin, David

    An electronic voting system may be said to be composed of a number of components, each of which has a number of properties. One of the most attractive effects of this way of thinking is that each component may have an attached in-depth threat analysis and verification strategy. Furthermore, the need to include the full system when making changes to a component is minimised and a model at this level can be turned into a lower-level implementation model where changes can cascade to as few parts of the implementation as possible.

  15. 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

  16. The computer assisted design of the custom prosthesis for acetabular dysplasia%成人髋臼发育不良的个性化股骨假体设计

    Institute of Scientific and Technical Information of China (English)

    刘国强; 白波; 孙辉; 廖壮文

    2009-01-01

    目的 探讨个性化股骨假体计算机辅助设计在成人髋臼发育不良(AD)行全髋关节置换术中的应用.方法 取1例AD女性患者的髋关节和股骨全长CT扫描数据,直接以Dicom格式导入Mimics 10.01矢量化处理后建立股骨三维模型,提取股骨髓腔轮廓并重组三维模型.上述模型通过Solid Work 2005完成假体的优化处理.最后利用Mimics平台装载STL功能以及手术模拟模块完成假体虚拟植入.结果 实现了基于CT二维资料的三维重建,设计的假体与患者股骨髓腔匹配良好,通过模拟假体良好装配帮助解决假体前倾角调整,髓腔匹配等一系列问题.结论 以现代CT扫描所获得的二维影像资料在Mimics的矢量化处理后能获得精确的股骨三维模型;提取股骨髓腔并重建模型方便准确,与计算机辅助设计软件相结合可以设计出个性化股骨假体.%Objective To explore the application of The computer assisted design of the custom prosthesis in total hip replacement for Acetabular Dysplasia(AD).Methods Imported the Dicom images of volunteer's femur of AD into the Mimics 10.01 to build the 3D model. Extracted the sketch of cavity of femur and rebuild the 3D model. Exported the model into the Solid Work 2005 to design the custom prosthesis and saved it as the STL file. Loaded the STL file in Mimics 10.01 and completed the virtual implantation.Results Get the 3D model based on the CT images. The custom made prosthesis matched well with the cavity of femur. Figured out the question of femoral neck anteversion through the simulated implantation of custom prosthesis.Conclusions The 3D model was precise base on the Mimics software. The method of extracting the sketch of femur was convenient and comfortable. It was a feasible way of custom prosthesis design and providing a wide prospective.

  17. 合并后壁骨折的复杂性髋臼骨折手术疗效分析%Analysis of Operative Treatment for Complex Acetabular Fractures Involving the Posterior Wall

    Institute of Scientific and Technical Information of China (English)

    孟纬; 潘昊鹏; 吕庆生; 朱伟

    2015-01-01

    目的:对手术治疗合并后壁骨折的复合髋臼骨折进行回顾性研究,评价其治疗效果。方法随访2003年8月至2013年8月采用切开复位内固定治疗的59例患者,其中横断伴后壁骨折41例,后柱伴后壁骨折18例。58例患者采用Kocher-Langenbeck 入路,1例患者采用联合入路( K-L 入路联合髂腹股沟入路)。采用改良的 Merle d′Aubigné和Postel评分系统评价临床效果,用Matta放射学标准评价影像学结果。结果59例患者平均随访4.3年(2.0~8.8年)。最终影像学结果:优23例(39%),良22例(37%),可10例(17%),差4例(7%),优良率76%。最终临床效果:优21例(36%),良26例(44%),可9例(15%),差3例(5%),优良率80%。结论对合并后壁骨折的复合髋臼骨折,切开复位内固定治疗可以获得满意效果。根据本组患者的治疗经验,对这类骨折推选双钢板固定。%Objective To evaluate the results of patients with operatively treated complex acetabular fractures involving the posterior wall retrospectively. Methods We reviewed fifty-nine patients who undurent open reduction and internal fixation of an unilateral fracture of the acetabulum between August 2003 to August 2013. Forty-one patients were diagnosed as trans-verse plus posterior wall fracture and eighteen patients were diagnosed as posterior column plus posterior wall fracture. The functional outcome was evaluated using a modification of the clinical grading system developed by Merled′Aubigné and Postel. The radiographs were graded according to the criteria described by Matta. Results Fifty-nine patients were followed for a mean of 4. 3 years(range,2. 0~8. 8 years). The radiographic result was excellent in twenty-three patients(39%),good in twenty-two(37%),fair in ten(17%),and poor in four(7%). The clinical outcome at the time of final follow-up was graded as excellent in twenty-one patients(36

  18. 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...

  19. 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,...

  20. 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...

  1. Formal aspects of component software

    OpenAIRE

    Sun, Meng; Schatz, B.

    2014-01-01

    This issue includes extended versions of selected best papers from the 7th International Workshop on Formal Aspects of Component Software (FACS 2010) held in Guimarães, Portugal on October 14–16, 2010. The component-based software development approach has emerged as a promising paradigm to cope with an ever increasing complexity of present-day software solutions by bringing sound production and engineering principles into software engineering. However, many conceptual and technological iss...

  2. Computed tomography in pelvic and acetabular fractures

    Energy Technology Data Exchange (ETDEWEB)

    Born, H.; Schmidt, C.

    1988-06-01

    In a retrospective study we analyzed the results of 127 patients, who were examined not only by means of conventional radiography but also by means of computed tomography after a trauma of the pelvic. Our investigations were based upon such patients, to whom a definite diagnostic procedure of plain radiography had been performed. Therefore all polytraumatized patients were inapplicable. They were only examined by computed tomography because of other more important accompanying injuries of other body regions. We compared the results of 127 patients with pelvic trauma. The results of the CT were in accordance with the results of the plain radiography for 103 patients. The results of the CT concerning the availability and the localization of the fractures were basically coincident with the plain radiography for 22 patients, but the CT showed a higher degree of trauma and additional intraarticular fragments. Two isolated lesions of the sacroiliac joint could not be recognized by both methods. They could only be diagnosed by bone scintigraphy on the third day after trauma.

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. Latent semantics as cognitive components

    DEFF Research Database (Denmark)

    Petersen, Michael Kai; Mørup, Morten; Hansen, Lars Kai