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Sample records for metal-on-metal hip prosthesis

  1. Breast milk metal ion levels in a young and active patient with a metal-on-metal hip prosthesis.

    Science.gov (United States)

    Nelis, Raymond; de Waal Malefijt, Jan; Gosens, Taco

    2013-01-01

    Metal-on-metal resurfacing arthroplasty of the hip has been used increasingly over the last 10 years in younger active patients. The dissolution of the metal wear particles results in measurable increases in cobalt and chromium ions in the serum and urine of patients with a metal-on-metal bearing. We measured the cobalt, chromium, and molybdenum ion levels in urine; serum; and breast milk in a young and active patient with a metal-on-metal hip prosthesis after a pathologic fracture of the femoral neck. Metal-on-metal hip prosthesis leads to increasing levels of molybdenum in breast milk in the short-term follow-up. There are no increasing levels of chromium and cobalt ions in breast milk. Besides the already known elevated concentrations in serum of chromium and cobalt after implantation of a metal-on-metal hip prosthesis, we found no increasing levels of chromium and cobalt in urine. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Albumin as marker for susceptibility to metal ions in metal-on-metal hip prosthesis patients.

    Science.gov (United States)

    Facchin, F; Catalani, S; Bianconi, E; Pasquale, D De; Stea, S; Toni, A; Canaider, S; Beraudi, A

    2017-04-01

    Metal-on-metal (MoM) hip prostheses are known to release chromium and cobalt (Co), which negatively affect the health status, leading to prosthesis explant. Albumin (ALB) is the main serum protein-binding divalent transition metals. Its binding capacity can be affected by gene mutations or modification of the protein N-terminal region, giving the ischaemia-modified albumin (IMA). This study evaluated ALB, at gene and protein level, as marker of individual susceptibility to Co in MoM patients, to understand whether it could be responsible for the different management of this ion. Co was measured in whole blood, serum and urine of 40 MoM patients. A mutational screening of ALB was performed to detect links between mutations and metal binding. Finally, serum concentration of total ALB and IMA were measured. Serum total ALB concentration was in the normal range for all patients. None of the subjects presented mutations in the investigated gene. Whole blood, serum and urine Co did not correlate with serum total ALB or IMA, although IMA was above the normal limit in most subjects. The individual susceptibility is very important for patients' health status. Despite the limited results of this study, we provide indications on possible future investigations on the toxicological response to Co.

  3. Effect of simplifications of bone and components inclination on the elastohydrodynamic lubrication modeling of metal-on-metal hip resurfacing prosthesis.

    Science.gov (United States)

    Meng, Qingen; Liu, Feng; Fisher, John; Jin, Zhongmin

    2013-05-01

    It is important to study the lubrication mechanism of metal-on-metal hip resurfacing prosthesis in order to understand its overall tribological performance, thereby minimize the wear particles. Previous elastohydrodynamic lubrication studies of metal-on-metal hip resurfacing prosthesis neglected the effects of the orientations of the cup and head. Simplified pelvic and femoral bone models were also adopted for the previous studies. These simplifications may lead to unrealistic predictions. For the first time, an elastohydrodynamic lubrication model was developed and solved for a full metal-on-metal hip resurfacing arthroplasty. The effects of the orientations of components and the realistic bones on the lubrication performance of metal-on-metal hip resurfacing prosthesis were investigated by comparing the full model with simplified models. It was found that the orientation of the head played a very important role in the prediction of pressure distributions and film profiles of the metal-on-metal hip resurfacing prosthesis. The inclination of the hemispherical cup up to 45° had no appreciable effect on the lubrication performance of the metal-on-metal hip resurfacing prosthesis. Moreover, the combined effect of material properties and structures of bones was negligible. Future studies should focus on higher inclination angles, smaller coverage angle and microseparation related to the occurrences of edge loading.

  4. The Management of the Symptomatic Patient With a Metal-on-Metal Hip Prosthesis.

    Science.gov (United States)

    Harrington, Kate; Phelan, Emma; Torreggiani, William C; Doody, Orla

    2016-02-01

    Metal-on-metal (MoM) hip implants have gained popularity due to their greater stability and reduction in implant failure compare to metal-on-polyethylene prostheses. However, as well as carrying general risks of hip implantation, risks specifically associated with MoM implants have been well documented in recent years. Conditions such as pseudotumours or aseptic lymphocyte-dominated vasculitis-associated lesions are specific to MoM hip implants. In this review we discuss the typical patient presentation, the investigations that should be performed, the typical findings on various imaging modalities, and the treatment options of symptomatic patients with MoM hip arthroplasties. Copyright © 2016 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

  5. Transient elastohydrodynamic lubrication analysis of a novel metal-on-metal hip prosthesis with a non-spherical femoral bearing surface.

    Science.gov (United States)

    Meng, Q E; Liu, F; Fisher, J; Jin, Z M

    2011-01-01

    Effective lubrication performance of metal-on-metal hip implants only requires optimum conformity within the main loaded area, while it is advantageous to increase the clearance in the equatorial region. Such a varying clearance can be achieved by using non-spherical bearing surfaces for either acetabular or femoral components. An elastohydrodynamic lubrication model of a novel metal-on-metal hip prosthesis using a non-spherical femoral bearing surface against a spherical cup was solved under loading and motion conditions specified by ISO standard. A full numerical methodology of considering the geometric variation in the rotating non-spherical head in elastohydrodynamic lubrication solution was presented, which is applicable to all non-spherical head designs. The lubrication performance of a hip prosthesis using a specific non-spherical femoral head, Alpharabola, was analysed and compared with those of spherical bearing surfaces and a non-spherical Alpharabola cup investigated in previous studies. The sensitivity of the lubrication performance to the anteversion angle of the Alpharabola head was also investigated. Results showed that the non-spherical head introduced a large squeeze-film action and also led to a large variation in clearance within the loaded area. With the same equatorial clearance, the lubrication performance of the metal-on-metal hip prosthesis using an Alpharabola head was better than that of the conventional spherical bearings but worse than that of the metal-on-metal hip prosthesis using an Alpharabola cup. The reduction in the lubrication performance caused by the initial anteversion angle of the non-spherical head was small, compared with the improvement resulted from the non-spherical geometry.

  6. Outcome and serum ion determination up to 11 years after implantation of a cemented metal-on-metal hip prosthesis.

    Science.gov (United States)

    Lazennec, Jean-Yves; Boyer, Patrick; Poupon, Joel; Rousseau, Marc-Antoine; Roy, Carine; Ravaud, Philippe; Catonné, Yves

    2009-04-01

    Little is known about the long-term outcome of cemented metal-on-metal hip arthroplasties. We evaluated a consecutive series of metal-on-metal polyethylene-backed cemented hip arthroplasties implanted in patients under 60 years of age. 109 patients (134 joint replacements) were followed prospectively for mean 9 (7-11) years. The evaluation included clinical score, radiographic assessment, and blood sampling for ion level determination. At the final review, 12 hips had been revised, mainly because of aseptic loosening of the socket. Using revision for aseptic loosening as the endpoint, the survival rate at 9 years was 91% for the cup and 99% for the stem. In addition, 35 hips showed radiolucent lines at the bone-cement interface of the acetabulum and some were associated with osteolysis. The median serum cobalt and chromium levels were relatively constant over time, and were much higher than the detection level throughout the study period. The cobalt level was 1.5 microg/L 1 year after implantation, and 1.44 microg/L 9 years after implantation. Revisions for aseptic loosening and radiographic findings in the sockets led us to halt metal-on-metal-backed polyethylene cemented hip arthroplasty procedures. If the rigidity of the cemented socket is a reason for loosening, excessive release of metal ions and particles may be involved. Further investigations are required to confirm this hypothesis and to determine whether subluxation, microseparation, and hypersensitivity also play a role.

  7. Metal-on-Metal Hip Resurfacing Arthroplasty

    Science.gov (United States)

    Sehatzadeh, S; Kaulback, K; Levin, L

    2012-01-01

    Background Metal-on-metal (MOM) hip resurfacing arthroplasty (HRA) is in clinical use as an appropriate alternative to total hip arthroplasty in young patients. In this technique, a metal cap is placed on the femoral head to cover the damaged surface of the bone and a metal cup is placed in the acetabulum. Objectives The primary objective of this analysis was to compare the revision rates of MOM HRA using different implants with the benchmark set by the National Institute of Clinical Excellence (NICE). The secondary objective of this analysis was to review the literature regarding adverse biological effects associated with implant material. Review Methods A literature search was performed on February 13, 2012, to identify studies published from January 1, 2009, to February 13, 2012. Results The revision rates for MOM HRA using 6 different implants were reviewed. The revision rates for MOM HRA with 3 implants met the NICE criteria, i.e., a revision rate of 10% or less at 10 years. Two implants had short-term follow-ups and MOM HRA with one of the implants failed to meet the NICE criteria. Adverse tissue reactions resulting in failure of the implants have been reported by several studies. With a better understanding of the factors that influence the wear rate of the implants, adverse tissue reactions and subsequent implant failure can be minimized. Many authors have suggested that patient selection and surgical technique affect the wear rate and the risk of tissue reactions. The biological effects of high metal ion levels in the blood and urine of patients with MOM HRA implants are not known. Studies have shown an increase in chromosomal aberrations in patients with MOM articulations, but the clinical implications and long-term consequences of this increase are still unknown. Epidemiological studies have shown that patients with MOM HRA implants did not have an overall increase in mortality or risk of cancer. There is insufficient clinical data to confirm the

  8. Heavy reading in heavy metal : Unraveling the mystery of hip tissue in metal on metal total hip arthroplasty

    NARCIS (Netherlands)

    Boomsma, M.F.

    2017-01-01

    In this thesis, we investigated the use of computer tomography (CT) for the screening of patients with a metal-on-metal (MoM) hip prosthesis in two patient cohorts. With a self-established CT grading scale, we have shown that CT is a reliable method for the diagnosis of postoperative pathological

  9. Revision rates for metal-on-metal hip resurfacing and metal-on-metal total hip arthroplasty - a systematic review.

    Science.gov (United States)

    Ras Sørensen, Sofie-Amalie L; Jørgensen, Henrik L; Sporing, Sune L; Lauritzen, Jes B

    2016-11-10

    To compare revision rates of metal-on-metal (MoM) hip resurfacing (HRS) and MoM total hip arthroplasty (THA), as well as the primary causes for revisions. The PubMed database was queried for potentially relevant articles addressing MoMTHA and MoMHRS, a total of 51 articles were included. The review includes a total number of 5,399 MoMHRS and 3,244 THA prosthesis and the reasons for prosthesis failure were divided into 7 categories and the main causes discussed. The overall MoMTHA revision rate was 4.7% after 6.9 years. MoMHRS revision rate was 5.9% after 5.7 years. The odds ratio was 1.25 (1.03:1.53) 95% CI (p = 0.03) (MoMHRS vs. MoMTHA).The studies of hip prostheses were separated into 2 categories of short- and long-term (more or less than 5 years). Short-term revision rate for MoMTHA was 4.5% after 4.8 years, and for MoMHRS 4.0% after 4.2 years. The odds ratio was 1.09 (0.82:1.43) 95% CI (0 = 0.56) (MoMTHA vs. MoMHRS). Long-term revision rate for MoMTHA was 5.2% after 7.7 years and 8.2% after 7.6 years for MoMHRS. The odds ratio was 1.58 (1.53:1.96) 95% CI (p = 0.0001) (MoMHRS vs. MoMTHA).Revision causes were divided into 7 main categories. The most common cause for revision for both MoMTHA and MoMHRS was loosening 47.6% vs. 37.7%, fracture (MoMTHA 7.69%; MoMHRS 19.62%), metal reactions (MoMTHA 7.69%; MoMHRS 26.92%) infection (MoMTHA 12.08%; MoMHRS 6.54%), instability (MoMTHA 9.13%; MoMHRS 2.69%), manufacturer defect 6.73% for MoMTHA and nonreported for MoMHRS, and miscellaneous (MoMTHA 7.69%; MoMHRS 6.54%) was stated. The comparison of MoMHRS and MoMTHA revision rates showed no difference in the short term, however in the longer term, the revision rate of MoMHRS was significantly higher than for MoMTHA. The linear increase in revision rate of MoMHRS may indicate a progression in failure.

  10. The effect of the metal-on-metal hip controversy on internet search activity.

    LENUS (Irish Health Repository)

    Phelan, Nigel

    2014-01-04

    The recall of the articular surface replacement (ASR) hip prosthesis in 2010 represents one of the most controversial areas in orthopaedic surgery in recent years. The aim of this study was to compare the impact of the metal-on-metal hip controversy on Internet search activity in four different regions and determine whether the number of related news reports affected Internet search activity. The Google Trends, Keywords and News applications were used to record the number of news articles and Internet search activity for the terms "hip recall", "metal-on-metal hip" and "ASR hip" from October 2009 to October 2012 in the USA, the UK, Australia and Ireland. There was a large increase in search activity following the official recall in August 2010 in all countries. There was significantly greater search activity after the recall in Ireland compared with the UK for the search term "hip recall" (P = 0.004). For the term "metal-on-metal hip", the UK had significantly more search activity (P = 0.0009). There was a positive correlation between the number of news stories in UK and Ireland with Internet search activity but not in the USA or Australia. Differences between countries affected by the same recall highlight the complex effects of the media on public awareness. The data demonstrates a window of opportunity prior to the official recall for the development of an awareness campaign to provide patients with accurate information.

  11. Fatal Cobalt Toxicity after a Non-Metal-on-Metal Total Hip Arthroplasty

    Directory of Open Access Journals (Sweden)

    Rinne M. Peters

    2017-01-01

    Full Text Available This case illustrates the potential for systemic cobalt toxicity in non-metal-on-metal bearings and its potentially devastating consequences. We present a 71-year-old male with grinding sensations in his right hip following ceramic-on-ceramic total hip arthroplasty (THA. After diagnosing a fractured ceramic liner, the hip prosthesis was revised into a metal-on-polyethylene bearing. At one year postoperatively, X-rays and MARS-MRI showed a fixed reversed hybrid THA, with periarticular densities, flattening of the femoral head component, and a pattern of periarticular metal wear debris and pseudotumor formation. Before revision could take place, the patient was admitted with the clinical picture of systemic cobalt toxicity, supported by excessively high serum cobalt and chromium levels, and ultimately died. At autopsy dilated cardiomyopathy as cause of death was hypothesized. A third body wear reaction between ceramic remnants and the metal femoral head very likely led to excessive metal wear, which contributed systemic cobalt toxicity leading to neurotoxicity and heart failure. This case emphasizes that fractured ceramic-on-ceramic bearings should be revised to ceramic-on-ceramic or ceramic-on-polyethylene bearings, but not to metal-on-polyethylene bearings. We aim to increase awareness among orthopedic surgeons for clinical clues for systemic cobalt intoxication, even when there is no metal-on-metal bearing surface.

  12. Metal on metal surface replacement of the hip. Experience of the McMinn prothesis.

    Science.gov (United States)

    McMinn, D; Treacy, R; Lin, K; Pynsent, P

    1996-08-01

    The historical failure of surface replacement has been due to the production of wear debris with subsequent bone resorption, loosening, and failure. To avoid these problems, a surface replacement using a metal on metal bearing allowing thin components and femoral design and instrumentation to avoid varus alignment has been designed. Two hundred thirty-five joints have been resurfaced with this prosthesis in almost 5 years. There have been no femoral neck fractures and no dislocations. There have been 4 designs differing in the method of fixation. In the press fit group, 6 of 70 hips had to be revised for aseptic loosening. In the cemented group, debonding of the cup occurred in 3 of 43 cases. Six patients had hydroxyapatite coated components and have had excellent clinical outcomes. The current design uses a peripherally expanded hydroxyapatite coated cup and a cemented metal head; 116 of this design have been implanted during a 19-month period with excellent outcome. Despite short followup the authors are hopeful that the combination of a polar metal on metal bearing with appropriate fixation will yield a method of preserving bone stock in the younger patient requiring arthroplasty.

  13. Inflammatory pseudotumor causing deep vein thrombosis after metal-on-metal hip resurfacing arthroplasty.

    LENUS (Irish Health Repository)

    Memon, Adeel Rasool

    2013-01-01

    Metal-on-metal hip resurfacings have recently been associated with a variety of complications resulting from adverse reaction to metal debris. We report a case of extensive soft tissue necrosis associated with a huge pelvic mass causing extensive deep vein thrombosis of the lower limb secondary to mechanical compression of the iliac vein. This is a rare and unusual cause of deep vein thrombosis after metal-on-metal hip resurfacing arthroplasty.

  14. Outcome of Revision Total Hip Arthroplasty in Management of Failed Metal-on-Metal Hip Arthroplasty.

    Science.gov (United States)

    Rahman, Wael A; Amenábar, Tomás; Hetaimish, Bandar M; Safir, Oleg A; Kuzyk, Paul R; Gross, Allan E

    2016-11-01

    This is a retrospective review of the functional outcomes and complications of revision total hip arthroplasty (THA) of failed metal-on-metal (MoM) hip arthroplasty. A total of 20 revision THAs were performed in 19 patients. Of them, 2 cases were failed hip resurfacing, and 18 cases were failed (MoM) THA. The mean age at revision (THA) was 59.35 years (standard deviation [SD] 9.83). The mean follow-up was 45 months (SD 13.98). The indications of revision were aseptic loosening of acetabular component without adverse local tissue reaction (ALTR; 10 hips), aseptic loosening of the acetabular and femoral components without ALTR (1 hip), painful hip associated with ALTR (6 hips), iliopsoas impingement associated with a large-diameter femoral head or malpositioned acetabular component (3 hips). The acetabular components were revised in 18 hips using Trabecular Metal Modular cups. The femoral components were revised in 3 hips. A constrained acetabular liner was used in 5 hips. The Harris hip score significantly improved from 48.4 (SD 12.98) to 83.25 (SD 10.08). There were 2 complications (1 foot drop and 1 superficial infection) and 1 failure (recurrent dislocation) that required revision to a constrained liner. Early results of revision THA of failed MoM hip arthroplasty showed improvement in pain and functional outcome. No case of failed bone ingrowth was noted with the use of Trabecular Metal Modular cups. Extensive soft tissue and abductor muscles dysfunctions were common. A constrained acetabular component with repair of the hip abductors might be beneficial. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Self-reported neurological clinical manifestations of metal toxicity in metal-on-metal hip arthroplasty

    NARCIS (Netherlands)

    van Lingen, Christiaan P.; Ettema, Harmen B.; Van Der Straeten, Catherine; Kollen, Bouwdewijn J.; Verheyen, Cees C. P. M.

    2014-01-01

    Adverse reactions to metal particle debris have been increasingly reported as a complication following large head metal-on-metal (MoM) hip arthroplasty. Elevated metal ion levels are a cause for concern. The aim of this study is to evaluate whether exposure to cobalt is associated with patient

  16. Asymptomatic pseudotumours after metal-on-metal hip resurfacing show little change within one year

    NARCIS (Netherlands)

    van der Weegen, W.; Brakel, K.; Horn, R. J.; Hoekstra, H. J.; Sijbesma, T.; Pilot, P.; Nelissen, R. G. H. H.

    2013-01-01

    The aim of this study was to establish the natural course of unrevised asymptomatic pseudotumours after metal-on-metal (MoM) hip resurfacing during a six- to 12-month follow-up period. We used repeated metal artefact reduction sequence (MARS)-magnetic resonance imaging (MRI), serum metal ion

  17. MRI of early symptomatic metal-on-metal total hip arthroplasty: a retrospective review of radiological findings in 20 hips

    International Nuclear Information System (INIS)

    Toms, A.P.; Marshall, T.J.; Cahir, J.; Darrah, C.; Nolan, J.; Donell, S.T.; Barker, T.; Tucker, J.K.

    2008-01-01

    Aim: To perform a retrospective review of all the conventional radiographic and magnetic resonance imaging (MRI) studies performed in patients with early postoperative pain following cobalt-chrome metal-on-metal total hip arthroplasty. Methods: A retrospective review of the radiology, surgical findings and histology in nineteen patients who had undergone a total of 20 hip arthroplasties using a cobalt-chromium on cobalt-chromium alloy prosthesis was undertaken. Results: Measures of implant placement on the immediate postoperative radiographs were all within the normal ranges (n = 20). Where more than one postoperative radiograph was available statistical analysis revealed no evidence of progressive change before the MRI examination (14). The median postoperative time to MRI was 35 months (range 11-63 months). Abnormalities were demonstrated using MRI in all symptomatic hips (n = 20). These comprised: periprosthetic fluid collections (20), which were isointense to muscle on T1-weighted images in 19 cases and hyperintense on T2-weighted images in 18 cases, periprosthetic bone marrow oedema (n = 6), muscle oedema (n = 4), avulsion of the gluteus minimus and medius tendons (n = 5), atrophy of piriformis (n = 15) and obturator internus (n = 17), and fracture of the medial calcar (n = 1). Operative findings in patients who had undergone revision surgery (n = 15) included: fluid-filled cavities (n = 11), soft tissue necrosis (n = 8), gluteal tendon avulsion (n = 5), proximal femoral diaphyseal necrosis (n = 4), and pitting and corrosion of the femoral stems (n = 8), which were, in all cases, firmly fixed to the cement mantle. Histology revealed viable tissue in six hips with necrosis (n = 12) and fibrin deposition (n = 15) being the predominate findings. Other findings included a perivascular lymphocytic infiltrate (n = 5), features of active inflammation (n = 4), and metallosis (n = 1). Conclusion: A significant number of patients with metal-on-metal hip replacements

  18. MRI of early symptomatic metal-on-metal total hip arthroplasty: a retrospective review of radiological findings in 20 hips

    Energy Technology Data Exchange (ETDEWEB)

    Toms, A.P. [Department of Radiology, Norfolk and Norwich University Hospital, Norwich, Norfolk (United Kingdom)], E-mail: andoni.toms@nnuh.nhs.uk; Marshall, T.J.; Cahir, J. [Department of Radiology, Norfolk and Norwich University Hospital, Norwich, Norfolk (United Kingdom); Darrah, C.; Nolan, J. [Department of Orthopaedics, Norfolk and Norwich University Hospital, Norwich, Norfolk (United Kingdom); Donell, S.T. [Institute of Health, University of East Anglia, Norwich, Norfolk (United Kingdom); Barker, T. [Department of Pathology, Norfolk and Norwich University Hospital, Norwich, Norfolk (United Kingdom); Tucker, J.K. [Department of Orthopaedics, Norfolk and Norwich University Hospital, Norwich, Norfolk (United Kingdom)

    2008-01-15

    Aim: To perform a retrospective review of all the conventional radiographic and magnetic resonance imaging (MRI) studies performed in patients with early postoperative pain following cobalt-chrome metal-on-metal total hip arthroplasty. Methods: A retrospective review of the radiology, surgical findings and histology in nineteen patients who had undergone a total of 20 hip arthroplasties using a cobalt-chromium on cobalt-chromium alloy prosthesis was undertaken. Results: Measures of implant placement on the immediate postoperative radiographs were all within the normal ranges (n = 20). Where more than one postoperative radiograph was available statistical analysis revealed no evidence of progressive change before the MRI examination (14). The median postoperative time to MRI was 35 months (range 11-63 months). Abnormalities were demonstrated using MRI in all symptomatic hips (n = 20). These comprised: periprosthetic fluid collections (20), which were isointense to muscle on T1-weighted images in 19 cases and hyperintense on T2-weighted images in 18 cases, periprosthetic bone marrow oedema (n = 6), muscle oedema (n = 4), avulsion of the gluteus minimus and medius tendons (n = 5), atrophy of piriformis (n = 15) and obturator internus (n = 17), and fracture of the medial calcar (n = 1). Operative findings in patients who had undergone revision surgery (n = 15) included: fluid-filled cavities (n = 11), soft tissue necrosis (n = 8), gluteal tendon avulsion (n = 5), proximal femoral diaphyseal necrosis (n = 4), and pitting and corrosion of the femoral stems (n = 8), which were, in all cases, firmly fixed to the cement mantle. Histology revealed viable tissue in six hips with necrosis (n = 12) and fibrin deposition (n = 15) being the predominate findings. Other findings included a perivascular lymphocytic infiltrate (n = 5), features of active inflammation (n = 4), and metallosis (n = 1). Conclusion: A significant number of patients with metal-on-metal hip replacements

  19. High Re-Operation Rates Using Conserve Metal-On-Metal Total Hip Articulations

    DEFF Research Database (Denmark)

    Mogensen, S L; Jakobsen, Thomas; Christoffersen, Hardy

    2016-01-01

    INTRODUCTION: Metal-on-metal hip articulations have been intensely debated after reports of adverse reactions and high failure rates. The aim of this study was to retrospectively evaluate the implant of a metal-on.metal total hip articulation (MOM THA) from a single manufacture in a two...... of 53 months. 4 pseudotumors were diagnosed at time of follow up but no substantiated link was made between adverse reactions and re-operations. CONCLUSION: The high re-operation rates found in this study raised concern about the usage of the MOM THA and subsequently lead to the termination......-center study. MATERIALS AND METHODS: 108 CONSERVE(®) MOM THA were implanted in 92 patients between November 2005 and December 2010. Patients had at time of retrospective evaluation their journals reviewed for re-operations and adverse reactions. RESULTS: 20 hips were re-operated (18.4%) at a mean follow up...

  20. Revision rates for metal-on-metal hip resurfacing and metal-on-metal total hip arthroplasty – a systematic review

    DEFF Research Database (Denmark)

    Ras Sørensen, Sofie-amalie L.; Jørgensen, Henrik L.; Sporing, Sune L.

    2016-01-01

    Purpose To compare revision rates of metal-on-metal (MoM) hip resurfacing (HRS) and MoM total hip arthroplasty (THA), as well as the primary causes for revisions. Methods The PubMed database was queried for potentially relevant articles addressing MoMTHA and MoMHRS, a total of 51 articles were...... cause for revision for both MoMTHA and MoMHRS was loosening 47.6% vs. 37.7%, fracture (MoMTHA 7.69%; MoMHRS 19.62%), metal reactions (MoMTHA 7.69%; MoMHRS 26.92%) infection (MoMTHA 12.08%; MoMHRS 6.54%), instability (MoMTHA 9.13%; MoMHRS 2.69%), manufacturer defect 6.73% for MoMTHA and nonreported...

  1. Few adverse reactions to metal on metal articulation in total hip arthroplasty in a review study on 358 consecutive cases with 1 to 5 years follow-up

    DEFF Research Database (Denmark)

    Stürup, Jens; Dahl, Line; Jensen, Karl Erik

    2012-01-01

    The aim of the present study was to determine the frequency of adverse reaction to metal on metal total hip arthroplasty using a M2a-38 articulation and a Magnum articulation, (Biomet Warsaw, Indiana).All patients who had received a Metal on Metal bearing prosthesis, in two centres in Copenhagen...... arthroplasty, who had an adverse reaction on one side. In addition the study showed that females had higher values of Co and Cr, and that younger patient reported groin pain more often.The conclusion of this study is that the number of adverse reactions is low, despite the time of observation being relatively...... short, no high frequency of adverse reactions to this prosthesis is expected....

  2. Uncemented metal-on-metal acetabular component: follow-up of 112 hips for a minimum of 5 years.

    Science.gov (United States)

    Vassan, Uma T; Sharma, Sanjeev; Chowdary, Koganti P; Bhamra, Manjit S

    2007-08-01

    Aseptic loosening is the major cause of implant failure. In cemented hip arthroplasty, failure of the acetabular side is mainly due to lysis caused by wear particles. By using an implant with low wear characteristics and by enhancing acetabular fixation using an uncemented implant, we aimed to reduce acetabular lysis and thereby loosening. This was a retrospective cohort study of 119 hips (101 patients) that had the Uncemented Fitmore cup (Sulzer Orthopedics). In 66 patients, the femoral component was CF-30 (Sulzer) used with cement. In the remaining 35 patients, thrust plate prosthesis (TPP) (Sulzer) was used. Of the 101 patients, 94 (112 hips) were available for study. Mean follow-up of the 94 patients was 7 (5-13) years. The mean preoperative Harris hip score was 38 and the mean postoperative Harris hip score was 89 at the last follow-up. Taking aseptic loosening as the endpoint, the survival rate of the Fitmore cup was 100% at 11 years. The uncemented Fitmore acetabular cup with second generation metal-on-metal articulation showed good results with regard to aseptic loosening in the medium term.

  3. The natural history of inflammatory pseudotumors in asymptomatic patients after metal-on-metal hip arthroplasty.

    Science.gov (United States)

    Almousa, Sulaiman A; Greidanus, Nelson V; Masri, Bassam A; Duncan, Clive P; Garbuz, Donald S

    2013-12-01

    Although pseudotumors have been reported in 32% of asymptomatic metal-on-metal hips, the natural history of asymptomatic pseudotumors is unknown. The purpose of this study was to assess changes over time in asymptomatic pseudotumors and the effect of revision on pseudotumor mass. Followup ultrasound was performed a mean of 25.8 months (range, 21-31 months) after the detection of 15 pseudotumors and five isolated fluid collections in a cohort of 20 asymptomatic patients (13 metal-on-metal, three metal-on-polyethylene, and four hip resurfacings) [42]. Changes in pseudotumors and fluid collections size and nature, and serum ion levels were determined. Among the 15 nonrevised patients, pseudotumors increased in size in six (four solid and two cystic) of 10 patients, three of which had clinically important increases (13-148 cm(3); 28-74 cm(3); 47-104 cm(3)). Three pseudotumors (one solid and two cystic) disappeared completely (the largest measured 31 cm(3)). One solid pseudotumor decreased in size (24 to 18 cm(3)). In five revised patients, pseudotumors completely disappeared in four patients. The fifth patient had two masses that decreased from 437 cm(3) to 262 cm(3) and 43 cm(3) to 25 cm(3). All revision patients had a reduction of chromium (40.42 μ/L to 2.69 μ/L) and cobalt ions (54.19 μ/L to 0.64 μ/L). Of five isolated fluid collections, four completely disappeared (two metal-on-metal and two metal-on-polyethylene) and one (metal-on-metal) increased from 26 cm(3) to 136 cm(3). Our observations suggest pseudotumors frequently increase in size in asymptomatic patients with occasional remission of small masses. Revision resulted in remission of pseudotumors.

  4. Nano-analyses of wear particles from metal-on-metal and non-metal-on-metal dual modular neck hip arthroplasty.

    Science.gov (United States)

    Xia, Zhidao; Ricciardi, Benjamin F; Liu, Zhao; von Ruhland, Christopher; Ward, Mike; Lord, Alex; Hughes, Louise; Goldring, Steven R; Purdue, Edward; Murray, David; Perino, Giorgio

    2017-04-01

    Increased failure rates due to metallic wear particle-associated adverse local tissue reactions (ALTR) is a significant clinical problem in resurfacing and total hip arthroplasty. Retrieved periprosthetic tissue of 53 cases with corrosion/conventional metallic wear particles from 285 revision operations for ALTR was selected for nano-analyses. Three major classes of hip implants associated with ALTR, metal-on-metal hip resurfacing arthroplasty (MoM HRA) and large head total hip replacement (MoM LHTHA) and non-metal-on-metal dual modular neck total hip replacement (Non-MoM DMNTHA) were included. The size, shape, distribution, element composition, and crystal structure of the metal particles were analyzed by conventional histological examination and electron microscopy with analytic tools of 2D X-ray energy dispersive spectrometry and X-ray diffraction. Distinct differences in size, shape, and element composition of the metallic particles were detected in each implant class which correlate with the histological features of severity of ALTR and variability in implant performance. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  5. INCIDENTALOMA FOUND IN A METAL-ON-METAL REVISION TOTAL HIP ARTHROPLASTY: A CASE REPORT.

    Directory of Open Access Journals (Sweden)

    Gabriele Falzarano

    2014-04-01

    Full Text Available Metal-on-metal coupling in total hip replacements has traditionally been a valid alternative to other total hip bearings for young adults and very active elderly patients. Unfortunately, clinical experience has revealed that the difference in strength between the titanium alloy stem and the cobalt alloy-bearing surface leads to a conflict between the acetabular component and the head, which inturn leads to abnormal wear and osteolysis. The major problems are osteolysis, metal ion intoxication, potential genome toxicity, neoplasms, allergies and implant failure. The authors present an incidental finding of a pseudotumour of the external rotators of the hip in a total hip replacement (THR revision in a 68 year old female patient.

  6. Early results of metal on metal articulation total hip arthroplasty in young patients.

    Science.gov (United States)

    Mohamad, J A; Kwan, M K; Merican, A M; Abbas, A A; Kamari, Z H; Hisa, M K; Ismail, Z; Idrus, R M

    2004-12-01

    We report our early experience of 20 cases of metal on metal articulation total hip arthroplasty in 19 young patients. Avascular necrosis of the femoral head (63%) was the commonest diagnosis for patients undergoing this procedure, followed by osteoarthritis (21%). In general, most of the patients were young and physically active with an average age of 43.1 years (range, 25 to 58 years). The average follow-up period was 18 months (range, 7 to 46 months). The mean total Harris Hip Score preoperatively and at final follow-up was 31 points and 89 points respectively. The mean total Pain Score improved from an average of 11.5 to 41.1 points at final follow-up. Sixteen (84%) of the patients had a good to excellent hip score. There was one dislocation, which stabilized after reduction and conservative management. One case of early infection underwent a two-staged revision.

  7. Longitudinal magnetic resonance imaging of pseudotumors following metal-on-metal total hip arthroplasty.

    Science.gov (United States)

    Hasegawa, Masahiro; Miyamoto, Noriki; Miyazaki, Shinichi; Wakabayashi, Hiroki; Sudo, Akihiro

    2014-12-01

    The purpose of the study was to determine the natural history of pseudotumors following metal-on-metal total hip arthroplasty (THA) using magnetic resonance imaging (MRI). Initial MRI was conducted at a mean of 36months postoperatively. Follow-up MRI was performed at a mean of 20months after the detection of 24 asymptomatic pseudotumors. Pseudotumor size was determined on MRI. The mean pseudotumor size changed from 729mm(2) to 877mm(2). Pseudotumors increased in size in eight and decreased in six. Ten hips showed no changes. The bigger the pseudotumor size, the more likely the size would increase. In conclusion, pseudotumors frequently change in size. A single MRI study in the clinical decision-making process should be avoided and a longitudinal study should be performed. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Edge loading in metal-on-metal hips: low clearance is a new risk factor.

    Science.gov (United States)

    Underwood, Richard J; Zografos, Angelos; Sayles, Ritchie S; Hart, Alister; Cann, Philippa

    2012-03-01

    The revision rate of large head metal-on-metal and resurfacing hips are significantly higher than conventional total hip replacements. The revision of these components has been linked to high wear caused by edge loading; which occurs when the head-cup contact patch extends over the cup rim. There are two current explanations for this; first, there is loss of entrainment of synovial fluid resulting in breakdown of the lubricating film and second, edge loading results in a large local increase in contact pressure and consequent film thickness reduction at the cup rim, which causes an increase in wear. This paper develops a method to calculate the distance between the joint reaction force vector and the cup rim--the contact patch centre to rim (CPCR) distance. However, the critical distance for the risk of edge loading is the distance from the contact patch edge to rim (CPER) distance. An analysis of explanted hip components, divided into edge worn and non-edge-worn components showed that there was no statistical difference in CPCR values, but the CPER value was significantly lower for edge worn hips. Low clearance hips, which have a more conformal contact, have a larger diameter contact patch and thus are more at risk of edge loading for similarly positioned hips.

  9. Balancing innovation and medical device regulation: the case of modern metal-on-metal hip replacements

    Directory of Open Access Journals (Sweden)

    Howard JJ

    2016-08-01

    Full Text Available Jason J Howard1,2 1Division of Orthopedic Surgery, Department of Surgery, Sidra Medical and Research Center, 2Department of Orthopedic Surgery, Weill Cornell Medical College, Doha, Qatar Abstract: Due to problems with wear particle generation and subsequent loosening using conventional metal-on-polyethylene total hip replacements, there has been a shift toward alternative bearing systems, including metal-on-metal (MoM, for younger, more active patients with degenerative joint disease. Based on positive results from early short-term clinical studies, MoM hip replacements were readily adopted by orthopedic surgeons with thousands being implanted worldwide over the past decade. Unacceptably high revision rates reported by two national joint registries called into question the rigorousness of the regulatory approval process for these implants, particularly with respect to premarket data requirements to prove safety, effectiveness, and the appropriateness of the regulatory pathway chosen. The purpose of this review was to investigate the balance between facilitating the introduction of new medical technologies and the need to ensure safety and effectiveness through comprehensive regulatory assessment. The case of MoM hip replacement devices was used to frame the investigation and subsequent discussions. The regulatory approval processes and post-market surveillance requirements associated with three common MoM hip replacements (two resurfacings: the Birmingham and articular surface replacement and the articular surface replacement XL total hip replacement were investigated. With respect to modern MoM hip replacement devices, the balance between facilitating the introduction of these new medical technologies and the need to ensure safety and effectiveness through comprehensive regulatory assessment was not achieved. The lessons learned from these experiences have application beyond joint replacements to the introduction of new medical technologies in

  10. Chromium and cobalt ion concentrations in blood and serum following various types of metal-on-metal hip arthroplasties

    DEFF Research Database (Denmark)

    Jantzen, Christopher; Jørgensen, Henrik L; Duus, Benn R

    2013-01-01

    Widely different metal ion concentrations in blood and serum have been reported with metal-on-metal (MoM) implants. We reviewed the literature on blood and serum ion concentrations of chromium (Cr) and cobalt (Co) following various MoM hip arthroplasties.......Widely different metal ion concentrations in blood and serum have been reported with metal-on-metal (MoM) implants. We reviewed the literature on blood and serum ion concentrations of chromium (Cr) and cobalt (Co) following various MoM hip arthroplasties....

  11. Poor Acetabular Component Orientation Increases Revision Risk in Metal-on-Metal Hip Arthroplasty.

    Science.gov (United States)

    Tauriainen, Tuomas J T; Niinimäki, Tuukka T; Niinimäki, Jaakko L; Nousiainen, Tomi O P; Leppilahti, Juhana I

    2017-07-01

    The rate of and the reasons for the failure of metal-on-metal (MoM) bearings have recently been discussed in literature. The aim of this study was to evaluate the influence of acetabular cup inclination and version angles on revision risk in patients with MoM hip arthroplasty. We retrospectively reviewed 825 patients (976 hips) who underwent a MoM hip arthroplasty between 2000 and 2013. There were 474 men and 351 women, with a mean age of 58 (19-86) years. Acceptable cup orientation was considered to be inside the Lewinnek's safe zone. The mean acetabular inclination angle was 48.9° (standard deviation, 8.1°; range, 16°-76°) and version angle 20.6° (standard deviation, 9.9°; range, -25 to 46°). The cup was found to be outside the Lewinnek's safe zone in 571 hips (58.5%). Acetabular cup revision surgery was performed in 157 hips (16.1%). The cup angles were outside Lewinnek's safe zone in 69.2% of the revised hips. The mean interobserver reliability and intraobserver repeatability of the measurements of cup inclination and version angles were excellent (intraclass correlation coefficients >0.90). The odds ratio for revision in hips outside vs inside the Lewinnek's safe zone was 1.82 (95% confidence interval, 1.26-2.62; P = .0014). Our findings provide compelling evidence that a cup position outside the Lewinnek's safe zone is associated with increased revision risk in patients with MoM arthroplasty. Copyright © 2017. Published by Elsevier Inc.

  12. Unusual presentation of failed metal-on-metal total hip arthroplasty with features of neoplastic process

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    Robert P. Runner, MD

    2017-06-01

    Full Text Available Metal-on-metal (MoM total hip arthroplasty (THA is associated with increased incidence of failure from metallosis, adverse tissue reactions, and the formation of pseudotumors. This case highlights a 53-year-old female with an enlarging painful thigh mass 12 years status post MoM THA. Radiographs and advanced imaging revealed an atypical mass with cortical bone destruction and spiculation, concerning for periprosthetic malignancy. Open frozen section biopsy was performed before undergoing revision THA in a single episode of care. This case illustrates that massive pseudotumors can be locally aggressive causing significant femoral bone destruction and may mimic malignancy. It is important that orthopaedic surgeons, radiologists and pathologists understand the relative infrequency of periprosthetic malignancy in MoM THA to mitigate patient concerns, misdiagnosis, and allow for an evidence based discussion when treating massive pseudotumors.

  13. Blood metal ion concentrations in metal-on-metal total hip arthroplasty.

    Science.gov (United States)

    Ohtsuru, Tadahiko; Morita, Yuji; Murata, Yasuaki; Shimamoto, Shuji; Munakata, Yutaro; Kato, Yoshiharu

    2017-05-01

    The hip placement with a metal-on-metal (MOM) bearing has been used for both surface replacement and total hip arthroplasty (THA). Use of MOM bearing for hip replacement reduces the wear compared to conventional bearings. We prospectively assessed 30 patients who underwent unilateral MOM THA. A control group of 30 patients who underwent metal-on-polyethylene THA using the implants as the other group, except for bearing, were accessed. Blood samples were collected preoperatively and at 3- , 6- , 9- , 12- , 15- , 18- , and 24-month intervals. Changes in mean blood metal ion concentration were compared between the MOM and metal-on-polyethylene groups. A statistically significant positive correlation was observed between blood cobalt and chromium concentrations in all of the patients. The mean blood ion concentrations of the MOM were significantly higher than those of the metal-on-polyethylene. A statistically significant negative correlation was found between maximum blood cobalt concentration and cup version angle. The maximum blood chromium concentrations in the patients who had larger cup version angles were more likely to decrease. We considered that cup version angle is one of the factors that have the greatest effect on blood metal ion concentration, and the target cup version angle that did not induce an increase in blood metal ion concentrations was approximately 20°.

  14. Large-diameter metal-on-metal total hip arthroplasties: a page in orthopedic history?

    Science.gov (United States)

    Singh, Gurpal; Meyer, Heiko; Ruetschi, Marcel; Chamaon, Kathrin; Feuerstein, Bernd; Lohmann, Christoph H

    2013-11-01

    Large-diameter metal-on-metal (MoM) bearings evolved from the success of hip resurfacing. These implants were used in revision surgery in cases with well-fixed acetabular cups but loose or failed femoral stems, to avoid cup revision. Early data showed low rates of dislocation and potentially low wear profiles due to better fluid film lubrication. The risk of impingement was also thought to be low due to the increased head-neck ratio. Subsequently large-diameter MoM heads gained popularity in primary hip replacement. Recent data has emerged on the unacceptably high revision rates among patients with large-diameter MoM total hip arthroplasties (THAs), high blood levels of metal ions, and adverse tissue reactions. The head-neck (cone-taper) modular interface probably represents the weak link in large metal heads that have been used on conventional tapers. Increased torque of the large head, micromotion, and instability at the cone-taper interface, synergistic interactions between corrosion and wear, edge loading, low clearance, and psoas impingement are the likely causes for early failure of these prostheses. Copyright © 2013 Wiley Periodicals, Inc.

  15. Current Insights Regarding Metal-on-Metal Bearings for Hip Arthroplasty

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    Catherine Van Der Straeten

    2017-09-01

    Full Text Available Modern small diameter metal-on-metal (MoM bearings for total hip arthroplasty (THA have been developed in the nineteen-eighties to address the problem of polyethylene wear related osteolysis. Subsequently large diameter MoM hip resurfacings (HRA were designed for young and active patients to preserve bone and avoid dislocation. Large diameter MoM THA were originally meant as an easy femoral component-only revision solution for femoral neck fractures in HRA, but were then advocated for primary THA as well. In the last decade however, increasing numbers of revisions for adverse local tissues reactions (ALTR to metal debris have been reported. These ALTR are due to excessive wear of the MoM bearings, usually related to malpositioning of the components leading to edge loading, or in rare cases to metal sensitivity. Besides the immunological reactions, metal particles and ions have a potential local and systemic toxicity. Wear and tribocorrosion at the taper-trunnion connections of MoM THA but also THA with polyethylene and ceramic bearings have also been recognized as a cause of ALTR with extensive tissue destruction. Despite the fact that the long-term survivorship and functional results of certain MoM HRA are excellent and better than THA in the young and active patients group, MoM bearings have become very unpopular and are likely to be replaced by bearing couples of other materials.

  16. Natural Remission of Major Periprosthetic Osteolysis following Total Hip Arthroplasty with Metal-on-Metal Bearings

    Directory of Open Access Journals (Sweden)

    Tatsuya Tamaki

    2017-01-01

    Full Text Available The natural course of adverse events following the use of metal-on-metal (MoM bearings in total hip arthroplasty (THA is not well known. In this article, we report the case of a patient with asymptomatic major acetabular osteolysis following MoM THA that diminished gradually without any surgical intervention. A 58-year-old male underwent one-stage bilateral MoM THA for bilateral osteoarthritis. Four years after THA, major acetabular osteolysis developed in his right hip without any local or systemic symptoms. The patient underwent a careful radiographic and clinical observation without any surgical intervention because he did not want to undergo revision surgery. The lesion gradually diminished after 7 years, and most of the osteolytic area was replaced by newly formed bone at 10 years. He continues to be followed with no evidence of cup loosening or migration. Our observation suggests that a periprosthetic osteolytic change related to the use of MoM bearings has the potential for natural remission.

  17. Histological characterization of periprosthetic tissue responses for metal-on-metal hip replacement

    Science.gov (United States)

    Phillips, Eual A.; Klein, Gregg R.; Cates, Harold E.; Kurtz, Steven M.; Steinbeck, Marla J.

    2014-01-01

    The histology of periprosthetic tissue from metal-on-metal (MOM) hip devices has been characterized by a variety of methods. The purpose of this study was to compare and evaluate the suitability of two previously developed aseptic lymphocyte-dominated vasculitis-associated lesions (ALVAL) scoring systems for periprosthetic hip tissue responses retrieved from MOM THR systems revised for loosening. Two ALVAL scoring systems (Campbell and Oxford) were used to perform histological analysis of soft tissues from seventeen failed MOM THRs. The predominant reactions for this patient cohort were macrophage infiltration and necrosis, with less than half of the patients (41%) showing a significant lymphocytic response or a high ALVAL reaction (6%). Other morphological changes which varied among patients included hemosiderin accumulation, cartilage formation and heterotopic ossification. Both scoring systems correlated with macrophage and lymphocyte responses and with each other, however given the diversity and variability of the current responses the Oxford-ALVAL system was more suitable for scoring tissues from MOM THR patients revised for loosening. It is important that standardized methods to score MOM tissue responses be used consistently so multiple study results can be compared to one another and a consensus can be generated. PMID:24941402

  18. The possibilities of magnetic resonance imaging in the diagnostics of complications after metal-on-metal hip arthroplasty

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    A. A. Vergay

    2013-01-01

    Full Text Available Objective: to find adverse periprosthetic local tissue reactions after metal-on-metal hip arthroplasty with ASR XL heads. Material and methods: 119 patients with 134 ASR XL head - Corail prostheses were treated in 2007-2009. The results were studied in 94 cases (105 prostheses - 84%. Average follow-up time consisted 62 ± 3 months. MRI was performed in 12 patients (13 hips who had clinical nonsatisfaction. Obtained data were compared with 21 MRI (24 hips of controlled group with good and perfect clinical results. Results. We found variations of normal periprosthetic tissue condition. Adverse reactions were identified in 10 cases. To improve the quality of pictures we developed special MRI adjustments and regimes of work. Conclusion: MRI diagnostics is indicated for the patients with metal-on-metal total hip arthroplasty in order to identify adverse local tissue reactions. The improvement of picture quality needs special adjustment of MRI equipment.

  19. What is the natural history of asymptomatic pseudotumours in metal-on-metal hip resurfacing patients?

    Science.gov (United States)

    Matharu, Gulraj S; Ostlere, Simon J; Pandit, Hemant G; Murray, David W

    2016-11-10

    We assessed the natural history of asymptomatic pseudotumours associated with metal-on-metal hip resurfacings (MoMHRs), and factors associated with future revision. In 2007-2008, we identified 25 MoMHRs (21 patients; mean age 59.9 years; 76% female) with asymptomatic pseudotumours. All patients underwent identical initial assessment (ultrasound, blood metal ions, radiographs, Oxford Hip Score [OHS]) and were considered asymptomatic because they denied experiencing hip symptoms, were satisfied with their MoMHR surgery, and had good or excellent OHSs (≥34). In 2012-2013, repeat assessments were performed in all non-revised patients. Revision for pseudotumour was performed/recommended in 15 MoMHRs (60%) at a mean 2.7 years (range 0.4-6.4 years) from initial assessment, with 14 developing symptoms before revision. Non-revised MoMHRs (n = 10) underwent repeat ultrasound at a mean 5.1 years (range 4.0-6.5 years) later, with no changes in pseudotumour volume (p = 0.956) or OHS (p = 0.065) between assessments. High blood cobalt (p = 0.0048) and chromium (p = 0.0162), large pseudotumours (p = 0.0458), low OHS (p = 0.0183), and bilateral MoMHRs (p = 0.049) predicted future revision. Patients with blood metal ions above established unilateral/bilateral thresholds and/or initial pseudotumours >30 cm3 had an 86.7% sensitivity, 70.0% specificity, 81.2% positive predictive value, and 77.8% negative predictive value for future revision. MoMHR patients with initially asymptomatic pseudotumours often become symptomatic and require revision. Patients with high blood metal ions and/or pseudotumours >30 cm3 should remain under annual surveillance or be considered for revision (especially in patients also having lower initial OHSs, bilateral MoMHRs, and/or those becoming symptomatic). Less regular surveillance of patients outside these parameters appears acceptable.

  20. The effect of motion patterns on edge-loading of metal-on-metal hip resurfacing.

    Science.gov (United States)

    Mellon, S J; Kwon, Y-M; Glyn-Jones, S; Murray, D W; Gill, H S

    2011-12-01

    The occurrence of pseudotumours (soft tissue masses relating to the hip joint) following metal-on-metal hip resurfacing arthroplasty (MoMHRA) has been associated with high serum metal ion levels and consequently higher than normal bearing wear. We investigated the relationship between serum metal ion levels and contact stress on the acetabular component of MoMHRA patients for two functional activities; gait and stair descent. Four subjects with MoMHRA, who had their serum metal ion levels measured, underwent motion analysis followed by CT scanning. Their motion capture data was combined with published hip contact forces and finite element models representing 14% (peak force) and 60% (end of stance) of the gait cycle and 52% (peak force) of stair descent activity were created. The inclination angle of the acetabular component was increased by 10° in 1° intervals and the contact stresses were determined at each interval for each subject. When the inclination angle was altered in such a way as to cause the hip contact force to pass through the edge of the acetabular component edge-loading occurred. Edge-loading increased the contact stress by at least 50%; the maximum increase was 108%. Patients with low serum metal ion levels showed no increase in contact stress at peak force during gait or stair descent. Patients with high serum metal ion levels exhibited edge-loading with an increase to the inclination angle of their acetabular components. The increase in inclination angle that induced edge-loading for these subjects was less than the inter-subject variability in the angle of published hip contact forces. The results of this study suggest that high serum metal ion levels are the result of inclination angle influenced edge-loading but that edge-loading cannot be attributed to inclination angle alone and that an individual's activity patterns can reduce or even override the influence of a steep acetabular component and prevent edge-loading. Copyright © 2011 IPEM

  1. Midterm results of 36 mm metal-on-metal total hip arthroplasty

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    Hawar Akrawi

    2016-01-01

    Full Text Available Background: Despite the many perceived benefits of metal-on-metal (MoM articulation in total hip arthroplasty (THA, there have been growing concerns about metallosis and adverse reaction to metal debris (ARMD. Analysis of size 36 mm MoM articulation THAs is presented. These patients were evaluated for patient characteristics, relationship between blood metal ions levels and the inclination as well as the version of acetabular component, cumulative survival probability at final followup and functional outcome at final followup. Materials and Methods: 288, size 36 mm MoM THAs implanted in 269 patients at our institution from 2004 to 2010 were included in this retrospective study. These patients were assessed clinically for hip symptoms, perioperative complications and causes of revision arthroplasty were analysed. Biochemically, blood cobalt and chromium metal ions level were recorded and measurements of acetabular inclination and version were examined. Radiological evaluation utilizing Metal Artefact Reduction Sequence (MARS MRI was undertaken and implant cumulative survivorship was evaluated. Results: The mean followup was 5 years (range 2–7 years, mean age was 73 years and the mean Oxford hip score was 36.9 (range 5–48. Revision arthroplasty was executed in 20 (7.4% patients, of which 15 patients underwent single-stage revision THA. The causes of revision arthroplasty were: ARMD changes in 6 (2.2% patients, infection in 5 (1.9% patients and aseptic loosening in 5 (1.9% patients. Three (1.1% patients had their hips revised for instability, 1 (0.3% for raised blood metal ions levels. The implant cumulative survival rate, with revision for any reason, was 68.9% at 7 years. Conclusions: Although medium-sized MoM THA with a 36 mm head has a marginally better survivorship at midterm followup, compared to larger size head MoM articulating THA, our findings nonetheless are still worryingly poor in comparison to what has been quoted in the

  2. Do cobalt and chromium levels predict osteolysis in metal-on-metal total hip arthroplasty?

    Science.gov (United States)

    Renner, Lisa; Schmidt-Braekling, Tom; Faschingbauer, Martin; Boettner, Friedrich

    2016-12-01

    Serum metal ions are part of the regular follow-up routine of patients with metal-on-metal total hip arthroplasties (MoM-THA). Increased cobalt levels have been suggested to indicate implant failure and corrosion. (1) Is there a correlation between the size of the osteolysis measured on a CT scan and metal ion levels? (2) Can metal ion levels predict the presence of osteolysis in MoM-THA? (3) Are cobalt and chromium serum levels or the cobalt-chromium-ratio diagnostic for osteolysis? CT scans of patients (n = 75) with a unilateral MoM-THA (Birmingham Hip System, Smith & Nephew, TN, USA) implanted by a single surgeon were reviewed to determine the presence of osteolysis. Statistical analysis was performed to detect its association with metal ion levels at the time of the imaging exam. The incidence of osteolysis was the same in men and women (35.6 vs 35.7 %). The cobalt-chromium-ratio correlates with the size of the osteolysis on the CT scan and the femoral component size in the overall study population (p = 0.050, p = 0.001) and in men (p = 0.002, p = 0.001) but not in women (p = 0.312, p = 0.344). The AUC for the cobalt-chromium-ratio to detect osteolysis was 0.613 (p = 0.112) for the overall population, 0.710 for men (p = 0.021) and 0.453 (p = 0.684) for women. The data suggest that a cut off level of 1.71 for the cobalt-chromium-ratio has a sensitivity of 62.5 % and specificity of 72.4 % to identify male patients with osteolysis. The disproportional increase of cobalt over chromium, especially in male patients with large component sizes can not be explained by wear alone and suggests that other processes (corrosion) might contribute to metal ion levels and might be more pronounced in patients with larger component sizes.

  3. Biomechanical evaluation of a metal-on-metal cervical intervertebral disc prosthesis.

    Science.gov (United States)

    Colle, Kyle O; Butler, John B; Reyes, Phillip M; Newcomb, Anna G U S; Theodore, Nicholas; Crawford, Neil R

    2013-11-01

    In vitro nondestructive flexibility testing of the CerviCore total disc replacement (TDR) was performed. It was hypothesized that TDR would not significantly alter biomechanics relative to intact, whereas rigid fixation would cause significant changes. To assess the ability of a cervical metal-on-metal saddle-shaped TDR to replicate normal biomechanics in vitro. Human cadaveric flexibility experiment. Nine human cadaveric C3-T1 specimens were tested intact, after TDR and after anterior plating. Flexion, extension, lateral bending, and axial rotation were induced by pure moments; flexion-extension was then repeated using a simplified muscle force model with 70-N follower load. Optical markers measured three-dimensional intervertebral motion, and eight points of laminar surface strain were recorded near the left and right C5-C6 facet joints. Biomechanical parameters studied included range of motion (ROM), lax zone (LZ), angular coupling pattern, sagittal instantaneous axis of rotation (IAR), and facet loads normal to the facet joint plane. Mean values of parameters were compared statistically using repeated measures analysis of variance and Holm-Sidak tests. Total disc replacement caused significant reduction in ROM during extension (p=.004) and significant reduction in LZ during lateral bending (p=.01). However, plating significantly reduced both ROM and LZ during flexion, extension, and lateral bending (p.05) and 6.5 mm after plating (p>.05). Coupled axial rotation/degree lateral bending was 99% of intact after TDR but 76% of intact after plating (p=.15). Coupled lateral bending/degree axial rotation was 95% of intact after TDR but 85% of intact after plating (p=.43). Neither construct altered facet loads from intact. With regard to ROM, LZ, IAR, and coupling, deviations from intact biomechanics were less substantial after TDR than after plating. Facet load alterations were minimal with either construct. Our results show that this particular TDR permits ROM and

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

    Directory of Open Access Journals (Sweden)

    van Raaij Jos JAM

    2008-10-01

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

  5. Increased risk of revision of cementless stemmed total hip arthroplasty with metal-on-metal bearings

    Science.gov (United States)

    Pedersen, Alma B; Mäkelä, Keijo; Eskelinen, Antti; Havelin, Leif Ivar; Furnes, Ove; Kärrholm, Johan; Garellick, Göran; Overgaard, Søren

    2015-01-01

    Background and purpose Data from the national joint registries in Australia and England and Wales have revealed inferior medium-term survivorship for metal-on-metal (MoM) total hip arthroplasty (THA) than for metal-on-polyethylene (MoP) THA. Based on data from the Nordic Arthroplasty Register Association (NARA), we compared the revision risk of cementless stemmed THA with MoM and MoP bearings and we also compared MoM THA to each other. Patients and methods We identified 32,678 patients who were operated from 2002 through 2010 with cementless stemmed THA with either MoM bearings (11,567 patients, 35%) or MoP bearings (21,111 patients, 65%). The patients were followed until revision, death, emigration, or the end of the study period (December 31, 2011), and median follow-up was 3.6 (interquartile range (IQR): 2.4–4.8) years for MoM bearings and 3.4 (IQR: 2.0–5.8) years for MoP bearings. Multivariable regression in the presence of competing risk of death was used to assess the relative risk (RR) of revision for any reason (with 95% confidence interval (CI)). Results The cumulative incidence of revision at 8 years of follow-up was 7.0% (CI: 6.0–8.1) for MoM bearings and 5.1% (CI: 4.7–5.6) for MoP bearings. At 6 years of follow-up, the RR of revision for any reason was 1.5 (CI: 1.3–1.7) for MoM bearings compared to MoP bearings. The RR of revision for any reason was higher for the ASR (adjusted RR = 6.4, CI: 5.0–8.1), the Conserve Plus (adjusted RR = 1.7, CI: 1.1–2.5) and “other” acetabular components (adjusted RR = 2.4, CI: 1.5–3.9) than for MoP THA at 6 years of follow-up. Interpretation At medium-term follow-up, the survivorship for cementless stemmed MoM THA was inferior to that for MoP THA, and metal-related problems may cause higher revision rates for MoM bearings with longer follow-up. PMID:25715878

  6. Complications Are Not Increased With Acetabular Revision of Metal-on-metal Total Hip Arthroplasty.

    Science.gov (United States)

    Penrose, Colin T; Seyler, Thorsten M; Wellman, Samuel S; Bolognesi, Michael P; Lachiewicz, Paul F

    2016-10-01

    Isolated revision of the acetabular component in the setting of total hip arthroplasty has an increased risk of dislocation. With local soft tissue destruction frequently associated with failed metal-on-metal (MoM) bearings, it is presumed that acetabular revision of these hips will have even greater risk of complications. However, no study directly compares the complications of MoM with metal-on-polyethylene (MoP) acetabular revisions. In the context of a large database analysis, we asked the following questions: (1) Are there differences in early medical or wound complications after isolated acetabular revision of MoM and MoP bearing surfaces? (2) Are there differences in the frequency of dislocation, deep infection, and rerevision based on the bearing surface of the original implant? A review of the 100% Medicare database from 2005 to 2012 was performed using International Classification of Diseases, 9th Revision and Current Procedural Terminology codes. We identified 451 patients with a MoM bearing and 628 patients with a MoP bearing who had an isolated acetabular revision and a minimum followup of 2 years. The incidence, odds ratios, and 95% confidence intervals for early medical or wound complications were calculated using a univariate analysis at 30 days with patient sex and age group-adjusted analysis for blood transfusion. The incidence, odds ratio, and 95% confidence intervals for dislocation, deep infection, and rerevision were calculated using a univariate analysis at 30 day, 90 days, 1 year, and 2 years using a subgroup analysis with the Cochran-Mantel-Haenszel test to adjust for patient gender and age groups. There were no differences between the MoM and MoP isolated acetabular revisions in the incidence of 30-day local complications. There was a greater risk of transfusion in the MoP group than the MoM group (134 of 451 [30%] versus 230 of 628 [37%]; odds ratio [OR], 0.731; 95% confidence interval [CI], 0.565-0.948; p = 0.018). There were no

  7. Contact mechanics and elastohydrodynamic lubrication in a novel metal-on-metal hip implant with an aspherical bearing surface.

    Science.gov (United States)

    Meng, Qingen; Gao, Leiming; Liu, Feng; Yang, Peiran; Fisher, John; Jin, Zhongmin

    2010-03-22

    Diameter and diametral clearance of the bearing surfaces of metal-on-metal hip implants and structural supports have been recognised as key factors to reduce the dry contact and hydrodynamic pressures and improve lubrication performance. On the other hand, application of aspherical bearing surfaces can also significantly affect the contact mechanics and lubrication performance by changing the radius of the curvature of a bearing surface and consequently improving the conformity between the head and the cup. In this study, a novel metal-on-metal hip implant employing a specific aspherical bearing surface, Alpharabola, as the acetabular surface was investigated for both contact mechanics and elastohydrodynamic lubrication under steady-state conditions. When compared with conventional spherical bearing surfaces, a more uniform pressure distribution and a thicker lubricant film thickness within the loaded conjunction were predicted for this novel Alpharabola hip implant. The effects of the geometric parameters of this novel acetabular surface on the pressure distribution and lubricant thickness were investigated. A significant increase in the predicted lubricant film thickness and a significant decrease in the dry contact and hydrodynamic pressures were found with appropriate combinations of these geometric parameters, compared with the spherical bearing surface. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  8. Histologic, serologic, and tribologic findings in failed metal-on-metal total hip arthroplasty: AAOS exhibit selection.

    Science.gov (United States)

    Pelt, Christopher E; Erickson, Jill; Clarke, Ian; Donaldson, Thomas; Layfield, Lester; Peters, Christopher L

    2013-11-06

    Despite multiple changes in second-generation metal-on-metal hip implants, greater-than-expected revision rates have led to alarm. We hypothesized that the finding of intraoperative metallosis would be associated with a high metal load on histologic analysis and that both would be associated with increased wear, greater serum metal ion levels, and predictable biologic responses in the histologic sections. We evaluated the implant positioning, serum ion levels, intraoperative findings of metallosis, wear characteristics of retrieved implants (tribology), histology, and outcomes in a series of eighteen large-diameter metal-on-metal total hip arthroplasties. The arthroplasties were divided into two groups on the basis of the intraoperative finding of metallosis and into two groups on the basis of the metal load score. Intraoperative metallosis was not associated with a high metal load score (p = 0.15). The finding of intraoperative metallosis was associated with greater serum metal ion levels, greater wear rates, and greater complication rates. Aseptic lymphocyte-dominated vasculitis-associated lesion (ALVAL) scores were similar between the metallosis and non-metallosis groups (p = 0.49) as well as between the high and low-metal-load groups (p = 0.56).

  9. A MRI classification of periprosthetic soft tissue masses (pseudotumours) associated with metal-on-metal resurfacing hip arthroplasty

    Energy Technology Data Exchange (ETDEWEB)

    Hauptfleisch, Jennifer; Ostlere, Simon [Nuffield Orthopaedic Centre, Oxford University Hospitals NHS Trust, Department of Radiology, Oxford (United Kingdom); Pandit, Hemant; Grammatopoulos, George; Gill, Harinderjit S.; Murray, David W. [Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS), University of Oxford, Botnar Research Centre, Oxford (United Kingdom)

    2012-02-15

    Metal-on-metal hip resurfacing arthroplasty (MoMHRA) has become a popular option for young patients requiring hip replacement. A recognised complication is the formation of a symptomatic reactive periprosthetic soft tissue mass (pseudotumour). We present a radiological classification system for these reactive masses, dividing them into three groups: Type I are thin-walled cystic masses (cyst wall <3 mm), Type II are thick-walled cystic masses (cyst wall >3 mm, but less than the diameter of the cystic component) and Type III are predominantly solid masses. We reviewed all MRI performed over a 4-year period in patients with primary MoMHRA referred to our institution. In all cases the masses were assessed on MRI according to size, anatomical position, signal intensity and involvement of bone, muscle or neighbouring neurovascular bundles. Periprosthetic masses were seen in 33 hips in 17 female (7 bilateral) and 8 male patients (1 bilateral). The Type I lesions were the most common and more likely to be posterior to the hip joint. The Type III masses were significantly larger than the cystic lesions and were more likely to be located anterior to the hip joint. To date 22 patients have undergone revision surgery with conversions to total hip replacement. Severity of symptoms and revision rates were lowest in the Type I group and highest in the Type III group. Solid anterior pseudotumours were most likely to have the more severe symptoms and require revision surgery. (orig.)

  10. Outcomes after revision of metal on metal hip resurfacing to total arthroplasty using the direct anterior approach.

    Science.gov (United States)

    Bouveau, Victoire; Haen, Thomas-Xavier; Poupon, Joel; Nich, Christophe

    2018-03-08

    Function after revision total hip arthroplasty (THA) in failed metal-on-metal (MoM) hip resurfacing arthroplasty (HRA) is variable, but post-operative complication rates are reportedly high. We hypothesized HRA conversion to THA using the direct anterior approach (DAA) would be associated with optimal outcome. Seventeen MoM-HRAs in 15 patients (seven males, eight females) were revised through the DAA. The mean age was 45 years (28-59 yrs). The most common indications for revision were aseptic loosening of the acetabular component or of the femoral component and femoral neck fracture. In 16 hips, a conversion to a ceramic-on-ceramic (CoC) (13 hips) or to a metal-on polyethylene (MOP) (2), or to a large-head MoM (1) THA was done. An isolated femoral revision was done in one hip. After 6.7 ± 3 years, no hip had required a re-revision. The Postel-Merle d'Aubigne (PMA) functional score improved from 9 (4-14) to 16 (12-18) (p hip) and dysesthesia of the lateral femoral cutaneous nerve (four hips) were reported. Mean serum chromium concentration decreased from 33.2 μg/L (11.8-62 μg/L) pre-operatively to 5.8 μg/L (0.4-35.5 μg/L) post-operatively (p Revision of failed MoM-HRA using the DAA resulted in an acceptable clinical outcome, no specific complication and no further surgery. A consistent decline in serum ion levels may be expected following HRA conversion to THA.

  11. Cobalt to Chromium Ratio is Not a Key Marker for Adverse Local Tissue Reaction (ALTR) in Metal on Metal Hips.

    Science.gov (United States)

    Fehring, Thomas K; Carter, Joshua L; Fehring, Keith A; Odum, Susan M; Griffin, William L

    2015-09-01

    The diagnosis of adverse local tissue reaction (ALTR) after metal-on-metal total hip arthroplasty (MoMTHA) presents a significant challenge. No single biomarker is specific for ALTR. The purpose of this study was to determine if the ratio of cobalt to chromium ions is useful for diagnosing ALTR in MoMTHA. In 89 bearing-related revision THAs, preoperative cobalt and chromium ion levels were compared to an intraoperative soft tissue damage grading scale. The average cobalt to chromium ratio was 2.96 (0-20). There was no correlation between the tissue scale and the cobalt to chromium ratio (R=0.095; P=0.41). Many variables affecting ion production/excretion mitigate the use of the ion ratio. The cobalt to chromium ratio is not a predictive biomarker for ALTR in MoMTHA. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. International metal-on-metal multidisciplinary teams: do we manage patients with metal-on-metal hip arthroplasty in the same way? An analysis from the International Specialist Centre Collaboration on MOM Hips (ISCCoMH).

    Science.gov (United States)

    Berber, R; Skinner, J; Board, T; Kendoff, D; Eskelinen, A; Kwon, Y-M; Padgett, D E; Hart, A

    2016-02-01

    There are many guidelines that help direct the management of patients with metal-on-metal (MOM) hip arthroplasties. We have undertaken a study to compare the management of patients with MOM hip arthroplasties in different countries. Six international tertiary referral orthopaedic centres were invited to participate by organising a multi-disciplinary team (MDT) meeting, consisting of two or more revision hip arthroplasty surgeons and a musculoskeletal radiologist. A full clinical dataset including history, blood tests and imaging for ten patients was sent to each unit, for discussion and treatment planning. Differences in the interpretation of findings, management decisions and rationale for decisions were compared using quantitative and qualitative methods. Overall agreement between the orthopaedic centres and the recommended treatment plans for the ten patients with MOM hip implants was moderate (kappa = 0.6). Full agreement was seen in a third of cases, however split decisions were also seen in a third of cases. Units differed in their interpretation of the significance of the investigation findings and put varying emphasis on serial changes, in the presence of symptoms. In conclusion, the management of raised or rising blood metal ions, cystic pseudotumours and peri-acetabular osteolysis led to inconsistency in the agreement between centres. Coordinated international guidance and MDT panel discussions are recommended to improve consensus in decision making. A lack of evidence and the subsequent variation in regulator guidance leads to differences in opinions, the clinical impact of which can be reduced through a multi-disciplinary team approach to managing patients with MOM hip implants. Cite this article: Bone Joint J 2016;98-B:179-86. ©2016 The British Editorial Society of Bone & Joint Surgery.

  13. Growth of an intrapelvic pseudotumor associated with a metal-on-metal total hip arthroplasty after revision arthroplasty causing a femoral nerve neuropathy

    Directory of Open Access Journals (Sweden)

    Patrick Leung, MD

    2016-09-01

    Full Text Available The development of pseudotumors is not uncommon with metal-on-metal total hip arthroplasty. Pseudotumors that dissect into the retroperitoneal space can cause symptoms of nerve compression. We describe a case of a 53-year-old male with a metal-on-metal total hip arthroplasty who developed mild symptoms of a femoral nerve neuropathy 6 years postoperatively. Revision arthroplasty to a ceramic-on-polyethylene articulation and debridement of the pseudotumor was performed. Postoperatively, the patient's femoral neuropathy progressed and a repeat magnetic resonance imaging showed an increase in size of the pseudotumor despite the removal of the offending metal-on-metal articulation. The patient subsequently underwent a laparoscopic excision of the retroperitoneal pseudotumor. By 17 months post laparoscopic excision of the pseudotumor, the patient's motor deficits resolved, however, sensory deficits persisted in the anteromedial thigh.

  14. Outcome of revision arthroplasty for failed metal-on-metal total hip replacements; is there a relation with metal ions?

    Science.gov (United States)

    Iqbal, Hafiz J; Al-Azzani, Waheeb A K; Jackson-Taylor, Esther; Clatworthy, Elizabeth; John, Alun

    2017-05-12

    We aimed to assess the early outcome following revision arthroplasty for failed metal-on-metal (MoM) total hip replacements (THR) due to adverse reaction to metal debris (ARMD). We reviewed 106 consecutive revision arthroplasties. Case notes and radiological investigations were reviewed to assess the complications. Oxford Hip Score (OHS) and Euroqol (EQ-5D-3L) scores were used to assess the functional outcome and improvement of quality of life. At a mean follow-up of 20 months (12-48 months), the mean OHS was 28.7. Pain improved in 61% patients. A majority of patients were in level 2 for all the EQ-5D-3L dimensions. The overall complication rate was 16%. Survivorship free from further revision for any cause was 94.3% at 48 months. There was no correlation between pre-revision blood metal ions and the final outcome. Revision surgery for failed MoM hip replacement due to ARMD is associated with a relatively higher rate of complications and risk of chronic pain. There is poor correlation between serum metal ions and development of ARMD and outcome following revision surgery.

  15. Effects of chronic cobalt and chromium exposure after metal-on-metal hip resurfacing: An epigenome-wide association pilot study.

    Science.gov (United States)

    Steinberg, Julia; Shah, Karan M; Gartland, Alison; Zeggini, Eleftheria; Wilkinson, Jeremy Mark

    2017-10-01

    Metal-on-metal (MOM) hip resurfacing has recently been a popular prosthesis choice for the treatment of symptomatic arthritis, but results in the release of cobalt and chromium ions into the circulation that can be associated with adverse clinical effects. The mechanism underlying these effects remains unclear. While chromosomal aneuploidy and translocations are associated with this exposure, the presence of subtle structural epigenetic modifications in patients with MOM joint replacements remains unexplored. Consequently, we analyzed whole blood DNA methylation in 34 OA patients with MOM hip resurfacing (MOM HR) compared to 34 OA patients with non-MOM total hip replacements (non-MOM THR), using the genome-wide Illumina HumanMethylation 450k BeadChip. No probes showed differential methylation significant at 5% false-discovery rate (FDR). We also tested association of probe methylation levels with blood chromium and cobalt levels directly; there were no significant associations at 5% FDR. Finally, we used the "epigenetic clock" to compare estimated to actual age at sample for all individuals. We found no significant difference between MOM HR and non-MOM THR, and no correlation of age acceleration with blood metal levels. Our results suggest the absence of large methylation differences systemically following metal exposure, however, larger sample sizes will be required to identify potential small effects. Any DNA methylation changes that may occur in the local periprosthetic tissues remain to be elucidated. © 2017 The Authors. Orthopaedic Research Society. Published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 35:2323-2328, 2017. © 2017 The Authors. Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  16. Crowe Type I and II DDH managed by large diameter metal-on-metal total hip arthroplasty.

    Science.gov (United States)

    Yalcin, Nadir; Kilicarslan, Kasim; Cicek, Hakan; Kayaalp, Cetin; Yildirim, Hasan

    2011-01-01

    Large bearing metal-on-metal (MOM) total hip arthroplasty (THA) may offer advantages relating to stability and range of motion in patients with Crowe Type I and II developmental dysplasia of the hip (DDH). The purpose of this study was to provide an analysis of the clinical and radiological results of MOM THA in this context and compare the results with a cohort of patients treated with metal-on-polyethylene (MOP) bearing surfaces. 75 hips in 65 patients were treated with cementless MOM THA using large femoral heads (36-56 mm). The mean age of the patients was 47.4 years (29 to 59) and 54 were female. A group of 47 hips (41 patients) treated with conventional THA (screwed cup-polyethylene insert-28 mm head) was used for comparison. The study group was followed up for a mean of 62.1 months (32 to 76). No difference was found between the two groups in relation to improvement in Harris hip score (HHS) (43.1 to 90.3 points in the study group, 42.6 to 89.5 points in the control group, p>0.05). Although the preoperative range of motion in all planes were similar in both groups, the large head group demonstrated greater motion in all planes postoperatively, which was significant (all p=0.001). Additionally, there was a significant difference between groups in relation to the necessity for acetabular structural graft (8% and 31.9%, respectively; p=0.001). No major complications or adverse reactions to metal debris (ARMD) were observed in the study group. The results of large head MOM THA in young and active patients with DDH are similar to conventional THA at early follow-up, but the former offers the advantages of secure acetabular fixation without screws, greater range of motion, and lower risk of dislocation.

  17. 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.

    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

  18. Relationship between Pelvic Incidence Angle and Blood Concentration of Chromium and Cobalt Ions after Metal-on-Metal Hip Replacement: A Brief Report.

    Science.gov (United States)

    Pernaa, K; Saltychev, M; Mäkelä, K

    2018-03-01

    The wear of metal-on-metal hip implants may increase chromium or cobalt ion blood level. This phenomenon may depend among other things on the particularity of spinopelvic anatomy. The effect of pelvic incidence angle on the wear of metal-on-metal hip implants is not known. The objective of the study was to investigate whether such effect does exist. The pelvic incidence and inclination of acetabular component angles of 89 patients after unilateral metal-on-metal hip replacement were compared with blood level of chromium and cobalt ions using Pearson correlation coefficient. No significant correlations between pelvic incidence angle and the metal ion blood levels were observed. The correlation coefficients varied from -0.02 to 0.2 and all p values were >0.05. No evidence was found on the effect of pelvic incidence angle on metal wear after metal-on-metal hip replacement when measured by the blood levels of chromium and cobalt ions. It is reasonable to assume that other factors than pelvic tilt may affect the rate of implant wear.

  19. Comparison of different pseudotumor grading systems in a single cohort of metal-on-metal hip arthroplasty patients

    Energy Technology Data Exchange (ETDEWEB)

    Weegen, W. van der; Wullems, J.A.; Das, H.P. [St. Anna Hospital, Department of Orthopaedic Surgery, Geldrop (Netherlands); Brakel, K.; Horn, R.J. [St. Anna Hospital, Department of Radiology, Geldrop (Netherlands); Pilot, P. [Reinier de Graaf Gasthuis, Department of Orthopaedic Surgery, Delft (Netherlands); Nelissen, R.G. [Leids Universitair Medisch Centrum, Department of Orthopaedic Surgery, Leiden (Netherlands)

    2014-02-15

    Follow-up of pseudotumors observed with metal-artefact reducing sequence (MARS)-magnetic resonance imaging (MRI) following metal-on-metal total hip arthroplasty (MoMTHA) depends on how severe these pseudotumors are graded. Several pseudotumor grading systems for MARS-MRI have emerged but little is known of their validity. We studied the intra- and interobserver reliability of three different pseudotumor grading systems in a single cohort of MoMTHA. Two experienced musculoskeletal radiologists independently used three different pseudotumor grading systems for classifying MARS-MRI results of the same cohort of 42 MoMTHA patients (49 hips, mean follow-up 5.2 years). Intraobserver and interobserver reliability for each grading system was measured using Cohen's kappa (κ). Variance in pseudotumor severity grading between systems was analyzed. Intraobserver reliability on grading pseudotumor severity with the Anderson, Matthies, and Hauptfleisch grading system scored 0.47, 0.10, and 0.35 (observer 1), and 0.75, 0.38, and 0.42 (observer 2), respectively. Interobserver reliability scores for pseudotumor severity were 0.58, 0.23, and 0.34, respectively. Intraobserver reliability for grading pseudotumor severity on MARS-MRI ranged from poor to good, dependent on observer and grading system used. Interobserver reliability scored best with the Anderson system. A more succinct pseudotumor severity grading system is needed for clinical use. (orig.)

  20. Clinical usefulness of blood metal measurements to assess the failure of metal-on-metal hip implants

    Science.gov (United States)

    Sampson, Barry; Hart, Alister

    2012-01-01

    In April 2010, a Medicines and Healthcare Products Regulatory Agency safety alert concerning all metal-on-metal (MOM) hip replacements recommended measuring chromium and cobalt concentrations when managing patients with painful prostheses. The need for this review is illustrated by the recent surge in requests for these blood tests from orthopaedic surgeons following this alert. The aim is to provide guidance to laboratories in assessing these requests and advising clinicians on interpretation. First, we summarize the basic terminology regarding the types of hip replacements, with emphasis on the MOM type. Second, we describe the clinical concerns over implant-derived wear debris in the local tissues and distant sites. Analytical aspects of the measurement of the relevant metal ions and what factors affect the levels measured are discussed. The application of inductively coupled plasma mass spectrometry techniques to the measurement of these metals is considered in detail. The biological effects of metal wear products are summarized with local toxicity and systemic biological effects considered, including carcinogenicity, genotoxicity and systemic toxicity. Clinical cases are used to illustrate pertinent points. PMID:22155921

  1. On the matter of synovial fluid lubrication: implications for Metal-on-Metal hip tribology.

    Science.gov (United States)

    Myant, Connor; Cann, Philippa

    2014-06-01

    Artificial articular joints present an interesting, and difficult, tribological problem. These bearing contacts undergo complex transient loading and multi axes kinematic cycles, over extremely long periods of time (>10 years). Despite extensive research, wear of the bearing surfaces, particularly metal-metal hips, remains a major problem. Comparatively little is known about the prevailing lubrication mechanism in artificial joints which is a serious gap in our knowledge as this determines film formation and hence wear. In this paper we review the accepted lubrication models for artificial hips and present a new concept to explain film formation with synovial fluid. This model, recently proposed by the authors, suggests that interfacial film formation is determined by rheological changes local to the contact and is driven by aggregation of synovial fluid proteins. The implications of this new mechanism for the tribological performance of new implant designs and the effect of patient synovial fluid properties are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Comparison of Complications Following Revision of Metal-on-Metal Versus Metal-on-Polyethylene Total Hip Arthroplasty.

    Science.gov (United States)

    Nishio, Shoji; Fukunishi, Shigeo; Yoshiya, Shinichi; Sing, David C; Hansen, Erik N; Vail, Thomas P

    2017-01-01

    The aim of this study was to examine the clinical characteristics of patients who required revision and the rate of early complications after revision for metal-on-metal total hip arthroplasty (MOM THA) and metal-on-polyethylene total hip arthroplasty (MOP THA). Matched cohorts were selected by retrospective review from a single-center database of revision THAs for failed MOM and MOP THAs from 2010 to 2014. A total of 140 hips in 140 patients comprised the study population; 39 revisions were performed for failed MOM THAs (MOM group), and 101 revisions were performed for failed MOP THAs (MOP group). Data included patient demographics, reason for revision, type of revision procedure, any complication within 90 days after surgery, admission type, and discharge disposition. Primary diagnosis, time from primary THA to revision, operative time, blood loss, and length of stay were reviewed. The analysis showed the time from the index primary procedure to first revision was earlier (P=.01) in the MOM group despite no significant intergroup differences in age, gender, primary diagnosis, or body mass index. Surgical morbidity, as indicated by operative time, blood loss, and length of stay, was lower in the MOM group. The stem was retained more often in the MOM group. There was no significant difference between the groups in overall complication rate. These findings indicate that when performed at an earlier time period before extensive soft tissue reaction to metal ions, revision following MOM THA is not associated with an increased complication rate compared with revision following MOP THA. [Orthopedics. 2017; 40(1):e164-e169.]. Copyright 2016, SLACK Incorporated.

  3. Increased Mortality in Metal-on-Metal versus Non-Metal-on-Metal Primary Total Hip Arthroplasty at 10 Years and Longer Follow-Up: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    B G Pijls

    Full Text Available There are concerns about increased mortality in patients with metal-on-metal bearings in total hip arthroplasty (THA.To determine the mortality and the morbidity in patients with metal-on-metal articulations (MOM THA compared to patients with non-metal-on-metal articulations (non-MOM THA after primary total hip arthroplasty.Search of PubMed, MEDLINE, EMBASE, Web of Science, Cochrane, CINAHL, AcademicSearchPremier, ScienceDirect, Wiley and clinical trial registers through March 2015, augmented by a hand search of references from the included articles. No language restrictions were applied.Two reviewers screened and identified randomised controlled trials and observational studies of primary total hip arthroplasty comparing MOM THA with non-MOM THA.Two reviewers independently extracted study data and assessed risk of bias. Risk differences (RD were calculated with random effect models. Meta-regression was used to explore modifying factors.Difference in mortality and difference in morbidity expressed as revisions and medical complications between patients with MOM THA and non-MOM THA.Forty-seven studies were included, comprising 4,000 THA in randomised trials and over 500,000 THA in observational studies. For mortality, random effects analysis revealed a higher pooled RD of 0.7%, 95%, confidence interval (CI [0.0%, 2.3%], I-square 42%; the heterogeneity was explained by differences in follow-up. When restricted to studies with long term follow-up (i.e. 10 years or more, the RD for mortality was 8.5%, 95%, CI [5.8%, 11.2%]; number needed to treat was 12. Further subgroup analyses and meta-regression random effects models revealed no evidence for other moderator variables (study level covariates, e.g. resurfacing vs. non-resurfacing MOM than follow-up duration. The quality of the evidence presented in this meta-analysis was characterized as moderate according to the CLEAR-NPT (for non-pharmacological trials and Cochrane risk of bias Table

  4. Outcomes following revision surgery performed for adverse reactions to metal debris in non-metal-on-metal hip arthroplasty patients

    Science.gov (United States)

    Judge, A.; Murray, D. W.; Pandit, H. G.

    2017-01-01

    Objectives Few studies have assessed outcomes following non-metal-on-metal hip arthroplasty (non-MoMHA) revision surgery performed for adverse reactions to metal debris (ARMD). We assessed outcomes following non-MoMHA revision surgery performed for ARMD, and identified predictors of re-revision. Methods We performed a retrospective observational study using data from the National Joint Registry for England and Wales. All non-MoMHAs undergoing revision surgery for ARMD between 2008 and 2014 were included (185 hips in 185 patients). Outcome measures following ARMD revision were intra-operative complications, mortality and re-revision surgery. Predictors of re-revision were identified using Cox regression. Results Intra-operative complications occurred in 6.0% (n = 11) of the 185 cases. The cumulative four-year patient survival rate was 98.2% (95% CI 92.9 to 99.5). Re-revision surgery was performed in 13.5% (n = 25) of hips at a mean time of 1.2 years (0.1 to 3.1 years) following ARMD revision. Infection (32%; n = 8), dislocation/subluxation (24%; n = 6), and aseptic loosening (24%; n = 6) were the most common re-revision indications. The cumulative four-year implant survival rate was 83.8% (95% CI 76.7 to 88.9). Multivariable analysis identified three predictors of re-revision: multiple revision indications (hazard ratio (HR) = 2.78; 95% CI 1.03 to 7.49; p = 0.043); selective component revisions (HR = 5.76; 95% CI 1.28 to 25.9; p = 0.022); and ceramic-on-polyethylene revision bearings (HR = 3.08; 95% CI 1.01 to 9.36; p = 0.047). Conclusions Non-MoMHAs revised for ARMD have a high short-term risk of re-revision, with important predictors of future re-revision including selective component revision, multiple revision indications, and ceramic-on-polyethylene revision bearings. Our findings may help counsel patients about the risks of ARMD revision, and guide reconstructive decisions. Future studies attempting to validate the predictors identified should also assess the

  5. Patient-Reported Outcomes After Revision of Metal-on-Metal Total Bearings in Total Hip Arthroplasty.

    Science.gov (United States)

    Mata-Fink, Ana; Philipson, Daniel J; Keeney, Benjamin J; Ramkumar, Dipak B; Moschetti, Wayne E; Tomek, Ivan M

    2017-04-01

    Failure of metal-on-metal (MOM) total hip arthroplasty (THA) bearings is often accompanied by an aggressive local reaction associated with destruction of bone, muscle, and other soft tissues around the hip. Little is known about whether patient-reported physical and mental function following revision THA in MOM patients is compromised by this soft tissue damage, and whether revision of MOM THA is comparable with revision of hard-on-soft bearings such as metal-on-polyethylene (MOP). We identified 75 first-time MOM THA revisions and compared them with 104 first-time MOP revisions. Using prospective patient-reported measures via the Veterans RAND-12, we compared Physical Component Score and Mental Component Score function at preoperative baseline and postoperative follow-up between revision MOM THA and revision MOP THA. Physical Component Score did not vary between the groups preoperatively and at 1 month, 3 months, and 1 year postoperatively. Mental Component Score preoperatively and 1 and 3 months postoperatively were lower in patients in the MOM cohort compared with patients with MOP revisions (baseline: 43.7 vs 51.3, P revision cohorts. Postrevision physical function in revised MOM THA patients does not differ significantly from the outcomes of revised MOP THA. Mental function is markedly lower in MOM patients at baseline and early in the postoperative period, but does not differ from MOP patients at 1 year after revision. This information should be useful to surgeons and physicians facing MOM THA revision. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Characterization of protein degradation in serum-based lubricants during simulation wear testing of metal-on-metal hip prostheses.

    Science.gov (United States)

    Maskiewicz, Victoria K; Williams, Paul A; Prates, Sarah J; Bowsher, John G; Clarke, Ian C

    2010-08-01

    A size exclusion high performance liquid chromatography (SEC-HPLC) method has been developed which is capable of separation and quantitation of bovine serum albumin (BSA) and bovine serum globulin (BSG) components of serum-based lubricant (SBL) solutions. This allowed characterization of the stability profiles of these proteins when acting as lubricants during hip wear simulation, and identification of wear-specific mechanisms of degradation. Using cobalt-chromium metal-on-metal (MOM) hip joints, it was observed that BSA remained stable for up to 3 days (215K cycles) of wear testing after which the protein degraded in a fairly linear fashion. BSG on the other hand, began to degrade immediately and in a linear fashion with a rate constant of 5% per day. Loss of both proteins occurred via the formation of high molecular weight aggregates which precipitated out of solution. No fragmentation of the polypeptide backbone of either protein was observed. Data obtained suggest that protein degradation was not due to microbial contamination, denaturation at the air-water interface, or frictional heating of articulating joint surfaces in these studies. We conclude that the primary source of protein degradation during MOM simulation testing occurs via high shear rates experienced by SBL solutions at articulating surfaces, possibly coupled with metal-protein interactions occurring as new and reactive metal surfaces are generated during wear testing. The development of this analytical methodology will allow new studies to clarify the role of SBL solutions in wear simulation studies and the interactions and lubricating properties of serum proteins with prosthetic surfaces other than MOM.

  7. Characterization of wear debris from metal-on-metal hip implants during normal wear versus edge-loading conditions.

    Science.gov (United States)

    Kovochich, Michael; Fung, Ernest S; Donovan, Ellen; Unice, Kenneth M; Paustenbach, Dennis J; Finley, Brent L

    2018-04-01

    Advantages of second-generation metal-on-metal (MoM) hip implants include low volumetric wear rates and the release of nanosized wear particles that are chemically inert and readily cleared from local tissue. In some patients, edge loading conditions occur, which result in higher volumetric wear. The objective of this study was to characterize the size, morphology, and chemistry of wear particles released from MoM hip implants during normal (40° angle) and edge-loading (65° angle with microseparation) conditions. The mean primary particle size by volume under normal wear was 35 nm (range: 9-152 nm) compared with 95 nm (range: 6-573 nm) under edge-loading conditions. Hydrodynamic diameter analysis by volume showed that particles from normal wear were in the nano- (edge-loading conditions generated particles that ranged from Edge-loading conditions generated more elongated particles (4.5%) (aspect ratio ≥ 2.5) and more CoCr alloy particles (9.3%) compared with normal wear conditions (1.3% CoCr particles). By total mass, edge-loading particles contained approximately 640-fold more cobalt than normal wear particles. Our findings suggest that high wear conditions are a potential risk factor for adverse local tissue effects in MoM patients who experience edge loading. This study is the first to characterize both the physical and chemical characteristics of MoM wear particles collected under normal and edge-loading conditions. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 986-996, 2018. © 2017 Wiley Periodicals, Inc.

  8. Total hip arthroplasty survival in femoral head avascular necrosis versus primary hip osteoarthritis: Case-control study with a mean 10-year follow-up after anatomical cementless metal-on-metal 28-mm replacement.

    Science.gov (United States)

    Ancelin, D; Reina, N; Cavaignac, E; Delclaux, S; Chiron, P

    2016-12-01

    Total hip arthroplasty is the most widely used procedure to treat avascular necrosis (AVN) of the femoral head. Few studies have compared the outcomes of THA in femoral head AVN and primary hip osteoarthritis. Therefore we performed a case-control study to compare THA for femoral head AVN vs. primary hip osteoarthritis in terms of: (1) prosthesis survival, (2) complication rates, (3) functional outcomes and radiographic outcomes, (4) and to determine whether specific risk factors for THA failure exist in femoral head AVN. THA survival is similar in femoral head AVN and primary hip osteoarthritis. We compared two prospective cohorts of patients who underwent THA before 65 years of age, one composed of cases with femoral head AVN and the other of controls with primary hip osteoarthritis. In both cohorts, a cementless metal-on-metal prosthesis with a 28-mm cup and an anatomical stem was used. Exclusion criteria were THA with other types of prosthesis, posttraumatic AVN, and secondary osteoarthritis. With α set at 5%, to obtain 80% power, 246 patients were required in all. Prosthesis survival was assessed based on time to major revision (defined as replacement of at least one implant fixed to bone) and time to aseptic loosening. The other evaluation criteria were complications, Postel-Merle d'Aubigné (PMA) score, and the Engh and Agora Radiographic Assessment (ARA) scores for implant osseointegration. The study included 282 patients, 149 with AVN and 133 with osteoarthritis. Mean age was 47.8±10.2 years (range, 18.5-65) and mean follow-up was 11.4±2.8 years (range, 4.5-18.3 years). The 10-year survival rates were similar in the two groups: for major revision, AVN group, 92.5% (95% confidence interval [95% CI], 90.2-94.8) and osteoarthritis group, 95.3% (95% CI, 92.9-97.7); for aseptic loosening, AVN group, 98.6% (95% CI, 97.6-98.6) and osteoarthritis, 99.2% (95% CI, 98.4-100). The AVN group had higher numbers of revision for any reason (19 vs. 6, P=0.018) and

  9. Revision of Metal-on-metal Hip Arthroplasty with Well Fixed and Positioned Acetabular Component Using a Dual-mobility Head and Review of Literature.

    Science.gov (United States)

    Figueras, Guillem; Planell, Ramón Vives; Fernàndez, Ramón Serra; Biayna, Joan Camí

    2016-01-01

    As a consequence of use of metal-on-metal hip arthroplasties some patients have precised revision for pain or metal hipersensivity reactions among other causes. We propose to salvage monoblock acetabular component and femoral component using a dual-mobility head and perform a lower morbidity operation in young patients preserving host bone stock in cases with well fixed and positioned components. (1) What clinical problems have been reported in patients with Metal-on-metal hip arthroplasties? (2) Could the tribocorrosion potentially cause a fracture of neck femoral component? (3) Can be the dual-mobility head a recourse in metal-on-metal hip revision? Ten patients were revised for pain or/and raised Cobalt/Chromium levels between August 2012 and December 2015. In three cases femoral neck component was fractured and femoral revision was necessary. In four hips, acetabular and femoral components could be maintained. Age, body index mass, ion levels, acetabular position, size of acetabular component and femoral head, approach, blood transfunsion and time of hospitalization were analized. At a mean follow-up of 25,6 months (6 to 45) the mean postoperative HHS was 92. It was not statistically significant because several patients were low sintomatic before surgery, but had raised Cobalt/Chromium levels in the blood. All patients had near-normal levels of Cobalt/Chromium during the first 6 months after revision surgery. No relevant complications were reported. The use of dual-mobility head can be an acceptable option to revise metal-on-metal arthroplasties correctly oriented with abscence of loosening or infection signs and keeping bone stock in young patients.

  10. Lymphoid Aggregates That Resemble Tertiary Lymphoid Organs Define a Specific Pathological Subset in Metal-on-Metal Hip Replacements

    Science.gov (United States)

    Barone, Francesca; Hardie, Debbie L.; Matharu, Gulraj S.; Davenport, Alison J.; Martin, Richard A.; Grant, Melissa; Mosselmans, Frederick; Pynsent, Paul; Sumathi, Vaiyapuri P.; Addison, Owen; Revell, Peter A.; Buckley, Christopher D.

    2013-01-01

    Aseptic lymphocyte-dominated vasculitis-associated lesion (ALVAL) has been used to describe the histological lesion associated with metal-on-metal (M-M) bearings. We tested the hypothesis that the lymphoid aggregates, associated with ALVAL lesions resemble tertiary lymphoid organs (TLOs). Histopathological changes were examined in the periprosthetic tissue of 62 M-M hip replacements requiring revision surgery, with particular emphasis on the characteristics and pattern of the lymphocytic infiltrate. Immunofluorescence and immunohistochemistry were used to study the classical features of TLOs in cases where large organized lymphoid follicles were present. Synchrotron X-ray fluorescence (XRF) measurements were undertaken to detect localisation of implant derived ions/particles within the samples. Based on type of lymphocytic infiltrates, three different categories were recognised; diffuse aggregates (51%), T cell aggregates (20%), and organised lymphoid aggregates (29%). Further investigation of tissues with organised lymphoid aggregates showed that these tissues recapitulate many of the features of TLOs with T cells and B cells organised into discrete areas, the presence of follicular dendritic cells, acquisition of high endothelial venule like phenotype by blood vessels, expression of lymphoid chemokines and the presence of plasma cells. Co-localisation of implant-derived metals with lymphoid aggregates was observed. These findings suggest that in addition to the well described general foreign body reaction mediated by macrophages and a T cell mediated type IV hypersensitivity response, an under-recognized immunological reaction to metal wear debris involving B cells and the formation of tertiary lymphoid organs occurs in a distinct subset of patients with M-M implants. PMID:23723985

  11. Prediction of contact mechanics in metal-on-metal Total Hip Replacement for parametrically comprehensive designs and loads.

    Science.gov (United States)

    Donaldson, Finn E; Nyman, Edward; Coburn, James C

    2015-07-16

    Manufacturers and investigators of Total Hip Replacement (THR) bearings require tools to predict the contact mechanics resulting from diverse design and loading parameters. This study provides contact mechanics solutions for metal-on-metal (MoM) bearings that encompass the current design space and could aid pre-clinical design optimization and evaluation. Stochastic finite element (FE) simulation was used to calculate the head-on-cup contact mechanics for five thousand combinations of design and loading parameters. FE results were used to train a Random Forest (RF) surrogate model to rapidly predict the contact patch dimensions, contact area, pressures and plastic deformations for arbitrary designs and loading. In addition to widely observed polar and edge contact, FE results included ring-polar, asymmetric-polar, and transitional categories which have previously received limited attention. Combinations of design and load parameters associated with each contact category were identified. Polar contact pressures were predicted in the range of 0-200 MPa with no permanent deformation. Edge loading (with subluxation) was associated with pressures greater than 500 MPa and induced permanent deformation in 83% of cases. Transitional-edge contact (with little subluxation) was associated with intermediate pressures and permanent deformation in most cases, indicating that, even with ideal anatomical alignment, bearings may face extreme wear challenges. Surrogate models were able to accurately predict contact mechanics 18,000 times faster than FE analyses. The developed surrogate models enable rapid prediction of MoM bearing contact mechanics across the most comprehensive range of loading and designs to date, and may be useful to those performing bearing design optimization or evaluation. Published by Elsevier Ltd.

  12. Small diameter metal-on-metal total hip arthroplasty at 13 years - a follow-up study.

    Science.gov (United States)

    Tardy, N; Maqdes, A; Boisrenoult, P; Beaufils, P; Oger, P

    2015-12-01

    Theoretically, the properties of second-generation metal-on-metal (MoM) bearings are better for wear, osteolysis and longevity. However, follow-up studies of more than 10 years are rare, in particular with hybrid fixation (cemented stainless steel stems and cementless cup), therefore we evaluated the results of this combination after a mean follow-up of 12.8 years: (1) to analyze the survival rate, (2) to compare it with the survival rate in the same series after 6.4 years (95.8% cup, 94.8% stem), (3) to evaluate clinical and radiographic outcome and (4) to analyze these failures. The number of revisions would increase after 10 years. We evaluated 106 total hip arthroplasties (THA) (Cedior™ press-fit cup with cemented Acora™ (n=50) and Exafit™ (n=56) stems and 28mm Metasul™ bearings performed between January 1999 and December 2002. The survival rate was calculated by the Kaplan-Meier method. The clinical assessment included the Postel Merle d'Aubigné (PMA) and Oxford scores. The radiographic assessment evaluated radiolucencies and osteolysis on standard X-rays. A histological analysis was only performed during revision THA. After a mean 12.8 years of follow-up (10-16), 53 THA were reviewed in 48 patients. Thirteen THA revisions (14%) were performed including 11 aseptic revisions (5 stem fractures, 2 cases of impingement and 3 loosenings [1 bipolar and 3 cups] and one case of osteolysis). Overall survival, taking into account revision for aseptic loosening, was 87.6% (CI 95%=77.3 to 99.3%). The mean PMA and Oxford scores at the final follow-up were 17.6±0.8 points (16-18) and 16.5±5.2 points (12-38) respectively. The radiological follow-up mainly identified radiolucencies around the stem in Gruen zones 1 and 7 (17 and 21% respectively). The survival rate of hybrid MoM THA in this series decreased after 10 years and is lower than studies evaluating cementless THA with the 28-mm Metasul™ bearings (90.9 to 100% survival). Although the clinical results are

  13. Distributed Analysis of Hip Implants Using Six National and Regional Registries: Comparing Metal-on-Metal with Metal-on-Highly Cross-Linked Polyethylene Bearings in Cementless Total Hip Arthroplasty in Young Patients

    Science.gov (United States)

    Furnes, Ove; Paxton, Elizabeth; Cafri, Guy; Graves, Stephen; Bordini, Barbara; Comfort, Thomas; Rivas, Moises Coll; Banerjee, Samprit; Sedrakyan, Art

    2014-01-01

    Background: The regulation of medical devices has attracted controversy recently because of problems related to metal-on-metal hip implants. There is growing evidence that metal-on-metal implants fail early and cause local and systemic complications. However, the failure associated with metal-on-metal head size is not consistently documented and needs to be communicated to patients and surgeons. The purpose of this study is to compare implant survival of metal on metal with that of metal on highly cross-linked polyethylene. Methods: Using a distributed health data network, primary total hip arthroplasties were identified from six national and regional total joint arthroplasty registries (2001 to 2010). Inclusion criteria were patient age of forty-five to sixty-four years, cementless total hip arthroplasties, primary osteoarthritis diagnosis, and exclusion of the well-known outlier implant ASR (articular surface replacement). The primary outcome was revision for any reason. A meta-analysis of survival probabilities was performed with use of a fixed-effects model. Metal-on-metal implants with a large head size of >36 mm were compared with metal-on-highly cross-linked polyethylene implants. Results: Metal-on-metal implants with a large head size of >36 mm were used in 5172 hips and metal-on-highly cross-linked polyethylene implants were used in 14,372 hips. Metal-on-metal total hip replacements with a large head size of >36 mm had an increased risk of revision compared with metal-on-highly cross-linked polyethylene total hip replacements with more than two years of follow-up, with no difference during the first two years after implantation. The results of the hazard ratios (and 95% confidence intervals) from the multivariable model at various durations of follow-up were 0.95 (0.74 to 1.23) at zero to two years (p = 0.698), 1.42 (1.16 to 1.75) at more than two years to four years (p = 0.001), 1.78 (1.45 to 2.19) at more than four years to six years (p implants and

  14. Advanced metal artifact reduction MRI of metal-on-metal hip resurfacing arthroplasty implants: compressed sensing acceleration enables the time-neutral use of SEMAC

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, Jan; Thawait, Gaurav K. [Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Section of Musculoskeletal Radiology, Baltimore, MD (United States); Fritz, Benjamin [University of Freiburg, Department of Radiology, Freiburg im Breisgau (Germany); Raithel, Esther; Nittka, Mathias [Siemens Healthcare GmbH, Erlangen (Germany); Gilson, Wesley D. [Siemens Healthcare USA, Inc., Baltimore, MD (United States); Mont, Michael A. [Cleveland Clinic Foundation, Department of Orthopedic Surgery, Cleveland, OH (United States)

    2016-10-15

    Compressed sensing (CS) acceleration has been theorized for slice encoding for metal artifact correction (SEMAC), but has not been shown to be feasible. Therefore, we tested the hypothesis that CS-SEMAC is feasible for MRI of metal-on-metal hip resurfacing implants. Following prospective institutional review board approval, 22 subjects with metal-on-metal hip resurfacing implants underwent 1.5 T MRI. We compared CS-SEMAC prototype, high-bandwidth TSE, and SEMAC sequences with acquisition times of 4-5, 4-5 and 10-12 min, respectively. Outcome measures included bone-implant interfaces, image quality, periprosthetic structures, artifact size, and signal- and contrast-to-noise ratios (SNR and CNR). Using Friedman, repeated measures analysis of variances, and Cohen's weighted kappa tests, Bonferroni-corrected p-values of 0.005 and less were considered statistically significant. There was no statistical difference of outcomes measures of SEMAC and CS-SEMAC images. Visibility of implant-bone interfaces and pseudocapsule as well as fat suppression and metal reduction were ''adequate'' to ''good'' on CS-SEMAC and ''non-diagnostic'' to ''adequate'' on high-BW TSE (p < 0.001, respectively). SEMAC and CS-SEMAC showed mild blur and ripple artifacts. The metal artifact size was 63 % larger for high-BW TSE as compared to SEMAC and CS-SEMAC (p < 0.0001, respectively). CNRs were sufficiently high and statistically similar, with the exception of CNR of fluid and muscle and CNR of fluid and tendon, which were higher on intermediate-weighted high-BW TSE (p < 0.005, respectively). Compressed sensing acceleration enables the time-neutral use of SEMAC for MRI of metal-on-metal hip resurfacing implants when compared to high-BW TSE and image quality similar to conventional SEMAC. (orig.)

  15. Usefulness of metal artifact reduction with WARP technique at 1.5 and 3T MRI in imaging metal-on-metal hip resurfacings

    Energy Technology Data Exchange (ETDEWEB)

    Lazik, Andrea; Lauenstein, Thomas C.; Theysohn, Jens M. [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Landgraeber, Stefan; Schulte, Patrick [University Hospital Essen, Department of Orthopedics, Essen (Germany); Kraff, Oliver [University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany)

    2015-03-25

    To evaluate the usefulness of the metal artifact reduction technique ''WARP'' in the assessment of metal-on-metal hip resurfacings at 1.5 and 3T in the context of image quality and imaging speed. Nineteen patients (25 hip resurfacings) were randomized for 1.5 and 3T MRI, both including T1 and T2 turbo spin-echo as well as turbo inversion recovery magnitude sequences with and without view angle tilting and high bandwidth. Additional 3T sequences were acquired with a reduced number of averages and using the parallel acquisition technique for accelerating imaging speed. Artifact size (diameter, area), image quality (5-point scale) and delineation of anatomical structures were compared among the techniques, sequences and field strengths using the Wilcoxon sign-rank and paired t-test with Bonferroni correction. At both field strengths, WARP showed significant superiority over standard sequences regarding image quality, artifact size and delineation of anatomical structures. At 3T, artifacts were larger compared to 1.5T without affecting diagnostic quality, and scanning time could be reduced by up to 64 % without quality degradation. WARP proved useful in imaging metal-on-metal hip resurfacings at 1.5T as well as 3T with better image quality surrounding the implants. At 3T imaging could be considerably accelerated without losing diagnostic quality. (orig.)

  16. Usefulness of metal artifact reduction with WARP technique at 1.5 and 3T MRI in imaging metal-on-metal hip resurfacings

    International Nuclear Information System (INIS)

    Lazik, Andrea; Lauenstein, Thomas C.; Theysohn, Jens M.; Landgraeber, Stefan; Schulte, Patrick; Kraff, Oliver

    2015-01-01

    To evaluate the usefulness of the metal artifact reduction technique ''WARP'' in the assessment of metal-on-metal hip resurfacings at 1.5 and 3T in the context of image quality and imaging speed. Nineteen patients (25 hip resurfacings) were randomized for 1.5 and 3T MRI, both including T1 and T2 turbo spin-echo as well as turbo inversion recovery magnitude sequences with and without view angle tilting and high bandwidth. Additional 3T sequences were acquired with a reduced number of averages and using the parallel acquisition technique for accelerating imaging speed. Artifact size (diameter, area), image quality (5-point scale) and delineation of anatomical structures were compared among the techniques, sequences and field strengths using the Wilcoxon sign-rank and paired t-test with Bonferroni correction. At both field strengths, WARP showed significant superiority over standard sequences regarding image quality, artifact size and delineation of anatomical structures. At 3T, artifacts were larger compared to 1.5T without affecting diagnostic quality, and scanning time could be reduced by up to 64 % without quality degradation. WARP proved useful in imaging metal-on-metal hip resurfacings at 1.5T as well as 3T with better image quality surrounding the implants. At 3T imaging could be considerably accelerated without losing diagnostic quality. (orig.)

  17. Life Estimation of Hip Joint Prosthesis

    Science.gov (United States)

    Desai, C.; Hirani, H.; Chawla, A.

    2014-11-01

    Hip joint is one of the largest weight-bearing structures in the human body. In the event of a failure of the natural hip joint, it is replaced with an artificial hip joint, known as hip joint prosthesis. The design of hip joint prosthesis must be such so as to resist fatigue failure of hip joint stem as well as bone cement, and minimize wear caused by sliding present between its head and socket. In the present paper an attempt is made to consider both fatigue and wear effects simultaneously in estimating functional-life of the hip joint prosthesis. The finite element modeling of hip joint prosthesis using HyperMesh™ (version 9) has been reported. The static analysis (load due to the dead weight of the body) and dynamic analysis (load due to walking cycle) have been described. Fatigue life is estimated by using the S-N curve of individual materials. To account for progressive wear of hip joint prosthesis, Archard's wear law, modifications in socket geometry and dynamic analysis have been used in a sequential manner. Using such sequential programming reduction in peak stress has been observed with increase in wear. Finally life is estimated on the basis of socket wear.

  18. Life Estimation of Hip Joint Prosthesis

    Science.gov (United States)

    Desai, C.; Hirani, H.; Chawla, A.

    2015-07-01

    Hip joint is one of the largest weight-bearing structures in the human body. In the event of a failure of the natural hip joint, it is replaced with an artificial hip joint, known as hip joint prosthesis. The design of hip joint prosthesis must be such so as to resist fatigue failure of hip joint stem as well as bone cement, and minimize wear caused by sliding present between its head and socket. In the present paper an attempt is made to consider both fatigue and wear effects simultaneously in estimating functional-life of the hip joint prosthesis. The finite element modeling of hip joint prosthesis using HyperMesh™ (version 9) has been reported. The static analysis (load due to the dead weight of the body) and dynamic analysis (load due to walking cycle) have been described. Fatigue life is estimated by using the S-N curve of individual materials. To account for progressive wear of hip joint prosthesis, Archard's wear law, modifications in socket geometry and dynamic analysis have been used in a sequential manner. Using such sequential programming reduction in peak stress has been observed with increase in wear. Finally life is estimated on the basis of socket wear.

  19. Cementless isoelastic RM total hip prosthesis1

    OpenAIRE

    Bombelli, Renato; Mathys, Robert

    1982-01-01

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

  20. Dislocation and spontaneous reduction of the femoral implant against the femoral neck in an infected metal on metal hip resurfacing with complex collection

    Energy Technology Data Exchange (ETDEWEB)

    Tins, Bernhard, E-mail: Bernhard.Tins@rjah.nhs.uk [Department of Radiology, RJAH Orthopaedic Hospital, Oswestry, Shropshire, SY 107 AG (United Kingdom)

    2011-07-15

    Metal on metal resurfacing hip implants are known to have complications unique to this type of implant. The case presented adds a further previously not described complication, the dislocation and spontaneous reduction of the pin of the femoral component against the femoral neck. The radiographic and CT findings are demonstrated. The dislocation was aided by bone loss due to an infection with a large periarticular collection. Periarticular collections in hip resurfacings are often due to a hypersensitivity type reaction to metal debris. However in the case presented it was due to infection. MRI was not able to discern the infection from a sterile collection. CT demonstrated bone loss and periosteal reaction suggestive of infection. In addition calcification of the pseudocapsule was seen, this is not a recognized feature of sterile collections.

  1. [Survivorship of the cemented hip prosthesis].

    Science.gov (United States)

    Kaczmarek, Wiesław; Ceglarz, Przemysław; Kucharski, Jakub; Pietrzak, Krzysztof; Pucher, Andrzej

    2010-01-01

    To asses a survival-time of the cemented hip prostheses and to find factors causing its loosening. 211 patients (282 hip prostheses) were analyzed, of the 1693 patients (2096 hip prostheses) treated between 1970-2000. The follow-up ranged from 7 to 34 years (mean: 12.2 ++/- 5.4 years). The age of the patients at the operation procedure ranged from 25 to 74 years (mean 52 +/- 12 years). Only aseptic prosthesis loosening were considered and Kaplan-Meyer method was used for the prosthesis survivorship assessment. Of the 282 prostheses, implant exchange was performed in 39 cases, where in 15 cases only cup was revised, in 5 cases the stem exclusively, and in 19 patients the whole implant was exchanged. Only 1.1% of implants were exchanged during first 5 years after surgery but from the 6th year the percentage of loosening increased several percents each year. Respectively 88.6, 70 and 65% survivorship of prosthesis was found after 10, 15, 20 years of follow-up. In the group of bilateral prosthesis implantation, the first implanted prosthesis was more susceptible for loosening. Seven cases of aseptic loosening (5.4%) of the 129 prostheses implanted between 1974 and 1995, occurred within 7 years after initial surgery where only one prosthesis (0.7%) was revised of the 152 implanted between 1996-2000 in the same time of follow-up. The age, growth, weight, BMI and sex did not influence the risk of implant loosening. The mean survivorship of the hip prosthesis is 65% in 20- years follow up. When a proper initial fixation of the cemented hip prosthesis is performed, the risk of implant loosening increases gradually especially from the 6th year after surgery. The modern implants are less susceptible for loosening.

  2. MR imaging with metal artifact-reducing sequences and gadolinium contrast agent in a case-control study of periprosthetic abnormalities in patients with metal-on-metal hip prostheses

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Gunilla M.; Mueller, Markus F.; Ekberg, Olle [Lund University, Skaane University Hospital, Department of Radiology, Malmoe (Sweden); Maansson, Sven [Lund University, Skaane University Hospital, Department of Medical Radiation Physics, Malmoe (Sweden); Schewelov, Thord von [Lund University, Skaane University Hospital, Department of Orthopedic Surgery, Malmoe (Sweden); Nittka, Mathias [Siemens AG, Healthcare Sector, Erlangen (Germany); Lundin, Bjoern [Lund University, Skaane University Hospital, Department of Radiology, Lund (Sweden)

    2014-08-15

    To apply and compare magnetic resonance imaging (MRI) metal artifact reducing sequences (MARS) including subtraction imaging after contrast application in patients with metal-on-metal (MoM) hip prostheses, investigate the prevalence and characteristics of periprosthetic abnormalities, as well as their relation with pain and risk factors. Fifty-two MoM prostheses (35 cases with pain and or risk factors, and 17 controls) in 47 patients were examined in a 1.5-T MR scanner using MARS: turbo spin echo (TSE) with high readout bandwidth with and without view angle tilting (VAT), TSE with VAT and slice encoding for metal artifact correction (SEMAC), short tau inversion recovery (STIR) with matched RF pulses, and post-contrast imaging. The relations of MRI findings to pain and risk factors were analyzed and in five revised hips findings from operation, histology, and MRI were compared. TSE VAT detected the highest number of osteolyses. Soft tissue mass, effusion, and capsular thickening were common, whereas osteolysis in acetabulum and femur were less frequent. Contrast enhancement occurred in bone, synovia, joint capsule, and the periphery of soft tissue mass. There was no significant relation between MRI findings and pain or risk factors. MARS and gadolinium subtraction imaging are useful for evaluation of complications to MoM prosthesis. TSE VAT had the highest sensitivity for osteolysis. Contrast enhancement might indicate activation of aseptic lymphocyte-dominated vasculitis-associated lesion (ALVAL). Pain, small head, or steep prosthesis inclination angle are not useful predictors of periprosthetic abnormalities, and wide indications for MR follow-up are warranted. (orig.)

  3. Surgical Approach May Influence Survival of Large-Diameter Head Metal-on-Metal Total Hip Arthroplasty: A 6- to 10-Year Follow-Up Study

    Directory of Open Access Journals (Sweden)

    Chih-Chien Hu

    2017-01-01

    Full Text Available Large-diameter head (LDH metal-on-metal (MoM total hip arthroplasty (THA has lost popularity because of metal allergy or ALTRs (adverse local tissue reactions in the past decade. Whether the surgical approach may influence the survival of LDH-MoM-THA has not been reported. From 2006 to 2009, we performed 96 LDH-MoM-THAs on 80 patients using an in situ head-neck assembly technique through a modified Watson-Jones approach. With a mean follow-up of 8.4 years (range, 6.3–10.1 years, the implant survival rate was 100%. All patients were satisfied with the results and the Harris Hip Score improved from 52 points to 98 points. No ALTRs were found, but 17.7% of the 96 hips (17 adverse events experienced adverse events related to the cup, including 5 cases of outlier cup malposition, 11 cases of inadequate cup seating, and 1 acetabular fracture. The tissue tension that was improved by a muscle-sparing approach might lessen the chance of microseparation or edge-loading that is taken as the major risk for early implant failure. Further investigation of whether these LDH-MoM-THAs would fail or not would require a longer follow-up or even retrieval analysis in the future.

  4. Grading the severity of soft tissue changes associated with metal-on-metal hip replacements: reliability of an MR grading system

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Helen; Cahir, John G.; Goodwin, Richard W. [Norfolk and Norwich University Hospital, Department of Radiology, Norwich, Norfolk (United Kingdom); Toms, Andoni Paul [Norfolk and Norwich University Hospital, Department of Radiology, Norwich, Norfolk (United Kingdom); Norwich Radiology Academy, Norwich (United Kingdom); Wimhurst, James; Nolan, John F. [Norfolk and Norwich University Hospital, Department of Orthopaedics, Norwich, Norfolk (United Kingdom)

    2011-03-15

    Metal-on-metal (MoM) soft tissue reactions or aseptic lymphocytic vasculitis-associated lesions (ALVAL) are being recognised using metal artefact reduction (MAR) MR with increasing frequency following the advent of second generation metal-on-metal bearings, but there is no standardised technique for reporting of MR appearances in this disease. The aim of this study was to measure the reliability of a grading system designed for scoring the severity of MoM disease on MRI. MRI examinations of 73 hips in 59 patients were retrospectively selected and then anonymised, randomised and reviewed by three independent observers (musculoskeletal radiologists). Each MR examination was scored as either A: normal, B: infection, C1: mild MoM disease, C2: moderate MoM disease or C3: severe MoM disease according to pre-defined criteria. Kappa correlation statistics were used to compare the observations. There was substantial agreement among all three observers; the correlation coefficient between the two most experienced observers was {kappa} = 0.78 [95% confidence intervals (CI): 0.68-0.88] and when compared with the least experienced observer coefficients were {kappa} = 0.69 (95% CI: 0.57-0.80) and {kappa} = 0.66 (95% CI: 0.54-0.78). The strongest correlation occurred for grades A, C2 and C3. The weakest correlations occurred for grades B and C1. The grading system described in this study is reliable for evaluating ALVAL in MoM prostheses using MR but is limited in differentiating mild disease from infection. (orig.)

  5. Pseudotumour incidence, cobalt levels and clinical outcome after large head metal-on-metal and conventional metal-on-polyethylene total hip arthroplasty MID-TERM RESULTS OF A RANDOMISED CONTROLLED TRIAL

    NARCIS (Netherlands)

    van der Veen, H. C.; Reininga, I. H. F.; Zijlstra, W. P.; Boomsma, M. F.; Bulstra, S. K.; van Raay, J. J. A. M.

    2015-01-01

    We compared the incidence of pseudotumours after large head metal-on-metal (MoM) total hip arthroplasty (THA) with that after conventional metal-on-polyethylene (MoP) THA and assessed the predisposing factors to pseudotumour formation. From a previous randomised controlled trial which compared large

  6. 21 CFR 888.3400 - Hip joint femoral (hemi-hip) metallic resurfacing prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3400 Section 888.3400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... femoral (hemi-hip) metallic resurfacing prosthesis. (a) Identification. A hip joint femoral (hemi-hip) metallic resurfacing prosthesis is a device intended to be implanted to replace a portion of the hip joint...

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

    Science.gov (United States)

    2010-04-01

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

  8. 21 CFR 888.3360 - Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... uncemented prosthesis. 888.3360 Section 888.3360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis. (a) Identification. A hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis is a device intended to be implanted...

  9. Patients with hip prosthesis: radiotherapy treatment planning considerations

    International Nuclear Information System (INIS)

    Ganesh, K.M.; Supe, Sanjay S.

    2000-01-01

    The number of patients with hip prosthesis undergoing radiotherapy for pelvic cancer worldwide is increasing. This might be of importance depending on the materials in the prosthesis and whether any of the treatment fields are involved in the prosthesis. Radiotherapy planning involving the pelvic region of patients having total hip prosthesis has been found to be difficult due to the effect of the prosthesis on the dose distribution. This review is intended to project dosimetric considerations and possible solutions to this uncommon problem

  10. Local tissue reaction and necrosis-induced femoral nerve palsy in a patient with a metal-on-metal total hip arthroplasty: a case report.

    Science.gov (United States)

    Wodowski, Andrew J; Rider, Carson M; Mihalko, William M

    2014-01-01

    This case report describes a 54-year-old Hispanic male who developed femoral nerve palsy approximately 1 year after metal-on-metal total hip arthroplasty (MOM THA). Cobalt and chromium levels were 4.8 ppb and undetectable, respectively. MRI demonstrated a well-encapsulated pseudotumor that communicated with the anterior portion of the right hip, and EMG showed neuropraxic femoral nerve injury. As a result, the patient experienced motor and sensory loss in the femoral and proximal saphenous nerve distributions. Surgical revision to ceramic-on-poly THA with debridement and decompression of the pseudotumor improved the patient's neurological status. Similar acute local tissue reactions have been described but the serum levels of cobalt and chrome associated with these reactions have been variable. Wear particles and products produced from corrosion at the head taper junction from MOM THA can potentially lead to cellular dysfunction with subsequent pseudotumer formation, but these reactions and fluid collections have also been found. In this patient, serum cobalt levels were elevated, while serum chromium levels remained undetectable. The purpose of this case report is to describe one patient's response and to review the recent literature regarding potential complications of MOM THA.

  11. Preoperative Risk Factors Associated With Poor Outcomes of Revision Surgery for "Pseudotumors" in Patients With Metal-on-Metal Hip Arthroplasty.

    Science.gov (United States)

    Liow, Ming Han Lincoln; Dimitriou, Dimitris; Tsai, Tsung-Yuan; Kwon, Young-Min

    2016-12-01

    Revision surgery of failed metal-on-metal (MoM) total hip arthroplasty (THA) for adverse tissue reaction (pseudotumor) can be challenging as a consequence of soft tissue and muscle necrosis. The aims of this study were to (1) report the revision outcomes of patients who underwent revision surgery for failed MoM hip arthroplasty due to symptomatic pseudotumor and (2) identify preoperative risk factors associated with revision outcomes. Between January 2011 and January 2013, a total of 102 consecutive large head MoM hip arthroplasties in 97 patients (male: 62, female: 35), who underwent revision surgery were identified from the database of a multidisciplinary referral center. At minimum follow-up of 2 years (range: 26-52 months), at least one complication had occurred in 14 of 102 revisions (14%). Prerevision radiographic loosening (P = .01), magnetic resonance imaging (MRI) findings of solid lesions with abductor deficiency on MRI (P revision complications. The reoperation rate of revised MoM THA was 7% (7 of 102 hips). Implant survivorship was 88% at 3 years. Metal ion levels declined in most patients after removal of MoM articulation. Revision outcomes of revision surgery for failed MoM THA due to symptomatic pseudotumor demonstrated 14% complication rate and 7% re-revision rate at 30-month follow-up. Our study identified prerevision radiographic loosening, solid lesions/abductor deficiency on MRI, and high grade intraoperative tissue damage as risk factors associated with poorer revision outcomes. This provides clinically useful information for preoperative planning and perioperative counseling of MoM THA patients undergoing revision surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Metal-on-metal hip resurfacing: correlation between clinical and radiological assessment, metal ions and ultrasound findings.

    Science.gov (United States)

    Scaglione, M; Fabbri, L; Bianchi, N; Dell'Omo, D; Guido, G

    2015-04-01

    We report the clinical, radiological and wear analysis of 52 consecutive MoM hip resurfacings (performed on 49 younger patients) to a mean follow-up of 9.2 years. Every patient underwent X-ray and clinical evaluation (HHS). Ultrasonography of the hip was performed in all patients in order to identify possible cystic or solid mass in periprosthetic tissue. In case of mass >20 mm, further MRI was performed to better analyse the characteristics of lesion. Five patients (five hips) had a revision. The overall survival rate was 90.38 %. The average HHS at follow-up examination was 95.5 points. No progressive radiolucent areas and no sclerosis or osteolysis around the implants were found. The US and RMI imaging showed a pseudotumour formation in two patients (correlated with high metal ion levels in blood and urine), both asymptomatic. A significant positive correlation between inclination of the acetabular component and serum metal ion levels was found (r = 0.64 and r = 0.62 for cobalt and chromium, respectively).

  13. Early results with the thrust plate prosthesis in young patients with osteoarthritis of the hip.

    Science.gov (United States)

    Sharma, Sanjeev; Verma, Gopalkrishna; Draviraj, Kingsley Paul; Bhamra, Manjit

    2005-04-01

    The purpose of this study was to evaluate the results of the Thrust Plate Prosthesis as a treatment option for osteoarthritis of the hip in young patients. Of the fifty patients (63 hips) reviewed, 31 (62%) were males and 19 (38%) females. Pre-operative diagnosis included primary osteoarthritis (23), developmental dysplasia (8), avascular necrosis (7), Perthes (4), post-traumatic arthritis (3), rheumatoid arthritis (2), ankylosing spondylitis (1), psoriatic arthropathy (1) and slipped upper femoral epiphysis (1). All components were implanted uncemented with metal-on-metal articulation. The average follow-up was 4.04 years (range 12 months-8.5 years). The mean age of the patients was 42.3 years (range 21-57 years). The mean pre-operative Harris Hip Score was 41.9 (range 12-89) and at final follow-up 89.91 (range 41-100). In 25 hips with > or = 5 yr follow-up, the average HHS at final follow-up was 84.5 (range 50-100). Complications included dislocation (2), transient sciatic nerve palsy (1), discomfort from lateral strap (2), implantation of wrong femoral head (1), revision (3 = 4.76%) and implant loosening (4) (6.35%). The thrust plate prosthesis is a useful alternative in young patients with hip arthritis and the results are comparable with other uncemented hip replacements. The added advantage is preservation of the proximal femoral bone stock, which can prove useful in future revisions.

  14. Block-step asymmetry 5 years after large-head metal-on-metal total hip arthroplasty is related to lower muscle mass and leg power on the implant side.

    Science.gov (United States)

    Hjorth, M H; Stilling, M; Lorenzen, N D; Jakobsen, S S; Soballe, K; Mechlenburg, I

    2014-06-01

    Metal-on-metal articulations mimic the human hip anatomy, presumably lower dislocation rates and increase the range-of-motion. This study aims to measure the muscle mass and power of both legs in patients with unilateral metal-on-metal total hip arthroplasty, and to investigate their effect on block-step test, spatio-temporal gait parameters and self-reported function. Twenty-eight patients (7 women), mean age 50 (28-68) years, participated in a 5-7 year follow-up. Patients had received one type unilateral large-head metal-on-metal total hip articulation, all of which were well-functioning at follow-up. Mean muscle mass was measured by the total-body Dual energy X-ray Absorption scans, and muscle power was measured in a leg extensor power rig. Block-step test and spatio-temporal gait parameters were measured with an inertial measurement unit. Self-reported function was assessed by the Hip Disability and Osteoarthritis Outcome Score. We found a significant difference between the mean muscle mass of the implant-side leg and the non-implant-side leg in hip, thigh and calf areas (Ppower (P=0.025). Correlations between mean muscle mass and mean muscle power were significant for both the implant-side leg (r=0.45, P=0.018) and the non-implant-side leg (r=0.51, P=0.007). The difference in mean muscle power between legs correlated with block-step test asymmetry during ascending (r=0.40, P=0.047) and descending (r=0.53, P=0.006). Correlations between self-reported function and power of the implant-side leg were not significant. Young patients have not fully regained muscle mass, muscle power and function 5-7 years after metal-on-metal total hip arthroplasty. Copyright © 2014. Published by Elsevier Ltd.

  15. Technical note: Comparison of metal-on-metal hip simulator wear measured by gravimetric, CMM and optical profiling methods

    Science.gov (United States)

    Alberts, L. Russell; Martinez-Nogues, Vanesa; Baker Cook, Richard; Maul, Christian; Bills, Paul; Racasan, R.; Stolz, Martin; Wood, Robert J. K.

    2018-03-01

    Simulation of wear in artificial joint implants is critical for evaluating implant designs and materials. Traditional protocols employ the gravimetric method to determine the loss of material by measuring the weight of the implant components before and after various test intervals and after the completed test. However, the gravimetric method cannot identify the location, area coverage or maximum depth of the wear and it has difficulties with proportionally small weight changes in relatively heavy implants. In this study, we compare the gravimetric method with two geometric surface methods; an optical light method (RedLux) and a coordinate measuring method (CMM). We tested ten Adept hips in a simulator for 2 million cycles (MC). Gravimetric and optical methods were performed at 0.33, 0.66, 1.00, 1.33 and 2 MC. CMM measurements were done before and after the test. A high correlation was found between the gravimetric and optical methods for both heads (R 2  =  0.997) and for cups (R 2  =  0.96). Both geometric methods (optical and CMM) measured more volume loss than the gravimetric method (for the heads, p  =  0.004 (optical) and p  =  0.08 (CMM); for the cups p  =  0.01 (optical) and p  =  0.003 (CMM)). Two cups recorded negative wear at 2 MC by the gravimetric method but none did by either the optical method or by CMM. The geometric methods were prone to confounding factors such as surface deformation and the gravimetric method could be confounded by protein absorption and backside wear. Both of the geometric methods were able to show the location, area covered and depth of the wear on the bearing surfaces, and track their changes during the test run; providing significant advantages to solely using the gravimetric method.

  16. Metal ion concentrations in body fluids after implantation of hip replacements with metal-on-metal bearing--systematic review of clinical and epidemiological studies.

    Directory of Open Access Journals (Sweden)

    Albrecht Hartmann

    Full Text Available INTRODUCTION: The use of metal-on-metal (MoM total hip arthroplasty (THA increased in the last decades. A release of metal products (i.e. particles, ions, metallo-organic compounds in these implants may cause local and/or systemic adverse reactions. Metal ion concentrations in body fluids are surrogate measures of metal exposure. OBJECTIVE: To systematically summarize and critically appraise published studies concerning metal ion concentrations after MoM THA. METHODS: Systematic review of clinical trials (RCTs and epidemiological studies with assessment of metal ion levels (cobalt, chromium, titanium, nickel, molybdenum in body fluids after implantation of metalliferous hip replacements. Systematic search in PubMed and Embase in January 2012 supplemented by hand search. Standardized abstraction of pre- and postoperative metal ion concentrations stratified by type of bearing (primary explanatory factor, patient characteristics as well as study quality characteristics (secondary explanatory factors. RESULTS: Overall, 104 studies (11 RCTs, 93 epidemiological studies totaling 9.957 patients with measurement of metal ions in body fluids were identified and analyzed. Consistently, median metal ion concentrations were persistently elevated after implantation of MoM-bearings in all investigated mediums (whole blood, serum, plasma, erythrocytes, urine irrespective of patient characteristics and study characteristics. In several studies very high serum cobalt concentrations above 50 µg/L were measured (detection limit typically 0.3 µg/L. Highest metal ion concentrations were observed after treatment with stemmed large-head MoM-implants and hip resurfacing arthroplasty. DISCUSSION: Due to the risk of local and systemic accumulation of metallic products after treatment with MoM-bearing, risk and benefits should be carefully balanced preoperatively. The authors support a proposed "time out" for stemmed large-head MoM-THA and recommend a restricted

  17. Metal Ion Concentrations in Body Fluids after Implantation of Hip Replacements with Metal-on-Metal Bearing – Systematic Review of Clinical and Epidemiological Studies

    Science.gov (United States)

    Hartmann, Albrecht; Hannemann, Franziska; Lützner, Jörg; Seidler, Andreas; Drexler, Hans; Günther, Klaus-Peter; Schmitt, Jochen

    2013-01-01

    Introduction The use of metal-on-metal (MoM) total hip arthroplasty (THA) increased in the last decades. A release of metal products (i.e. particles, ions, metallo-organic compounds) in these implants may cause local and/or systemic adverse reactions. Metal ion concentrations in body fluids are surrogate measures of metal exposure. Objective To systematically summarize and critically appraise published studies concerning metal ion concentrations after MoM THA. Methods Systematic review of clinical trials (RCTs) and epidemiological studies with assessment of metal ion levels (cobalt, chromium, titanium, nickel, molybdenum) in body fluids after implantation of metalliferous hip replacements. Systematic search in PubMed and Embase in January 2012 supplemented by hand search. Standardized abstraction of pre- and postoperative metal ion concentrations stratified by type of bearing (primary explanatory factor), patient characteristics as well as study quality characteristics (secondary explanatory factors). Results Overall, 104 studies (11 RCTs, 93 epidemiological studies) totaling 9.957 patients with measurement of metal ions in body fluids were identified and analyzed. Consistently, median metal ion concentrations were persistently elevated after implantation of MoM-bearings in all investigated mediums (whole blood, serum, plasma, erythrocytes, urine) irrespective of patient characteristics and study characteristics. In several studies very high serum cobalt concentrations above 50 µg/L were measured (detection limit typically 0.3 µg/L). Highest metal ion concentrations were observed after treatment with stemmed large-head MoM-implants and hip resurfacing arthroplasty. Discussion Due to the risk of local and systemic accumulation of metallic products after treatment with MoM-bearing, risk and benefits should be carefully balanced preoperatively. The authors support a proposed „time out“ for stemmed large-head MoM-THA and recommend a restricted indication for hip

  18. What Is the Natural History of "Asymptomatic" Pseudotumours in Metal-on-Metal Hip Arthroplasty? Minimum 4-Year Metal Artifact Reduction Sequence Magnetic Resonance Imaging Longitudinal Study.

    Science.gov (United States)

    Kwon, Young-Min; Liow, Ming Han Lincoln; Dimitriou, Dimitris; Tsai, Tsung-Yuan; Freiberg, Andrew A; Rubash, Harry E

    2016-09-01

    Metal Artifact Reduction Sequence Magnetic Resonance Imaging (MARS-MRI) is an important cross-sectional imaging modality in detection of metal-on-metal (MoM) hip arthroplasty (HA) pseudotumours. Potential evolution of pseudotumours detected by MARS-MRI in "asymptomatic" patients with MoMHA arthroplasty beyond 2 years remains largely unknown. The aims of this longitudinal study were to (1) determine the natural history of pseudotumours in "asymptomatic" MoMHA patients under MARS-MRI surveillance and (2) characterize MRI feature(s) associated with progressive pseudotumours. A total of 37 MoMHA (32 patients, mean 56 years old) with pseudotumours on MARS-MRI were evaluated longitudinally using a standardized MARS-MRI protocol. Serum cobalt and chromium levels, pseudotumour size, thickness of the cyst wall, and MRI signal intensity of the abnormality were recorded and analyzed. At minimum of 4-year follow-up (range 49-54 months), 4 Type II pseudotumours (11%) demonstrated MRI evidence of progression. Five Type I pseudotumours (14%) were found to have "regressed." No measurable MRI progression was detected in remaining patients (75%). MRI features associated with progressive pseudotumours included the presence of increased cystic wall thickness and "atypical" mixed fluid signal. MRI pseudotumour progression was not associated with metal ion levels. The natural history of type I cystic pseudotumours continues to be nonprogressive in most "asymptomatic" MoMHA patients at minimum 4 years, suggesting the importance of patient symptoms and MRI characteristic features in the clinical decision-making process. Routine follow-up MARS-MRI evaluation of "asymptomatic" patients with low-grade cystic pseudotumours in the absence of interval clinical changes may not be indicated. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Comparison of metal ion concentrations and implant survival after total hip arthroplasty with metal-on-metal versus metal-on-polyethylene articulations.

    Science.gov (United States)

    Dahlstrand, Henrik; Stark, André; Wick, Marius C; Anissian, Lucas; Hailer, Nils P; Weiss, Rüdiger J

    2017-10-01

    Background and purpose - Large metal-on-metal (MoM) articulations are associated with metal wear and corrosion, leading to increased metal ion concentrations and unacceptable revision rates. There are few comparative studies of 28-mm MoM articulations with conventional metal-on-polyethylene (MoP) couplings. We present a long-term follow-up of a randomized controlled trial comparing MoM versus MoP 28-mm articulations, focused on metal ions and implant survival. Patients and methods - 85 patients with a mean age of 65 years at surgery were randomized to a MoM (Metasul) or a MoP (Protasul) bearing. After 16 years, 38 patients had died and 4 had undergone revision surgery. 13 patients were unavailable for clinical follow-up, leaving 30 patients (n = 14 MoM and n = 16 MoP) for analysis of metal ion concentrations and clinical outcome. Results - 15-year implant survival was similar in both groups (MoM 96% [95% CI 88-100] versus MoP 97% [95% CI 91-100]). The mean serum cobalt concentration was 4-fold higher in the MoM (1.5 μg/L) compared with the MoP cohort (0.4 μg/L, p concentration was double in the MoM (2.2 μg/L) compared with the MoP cohort (1.0 μg/L, p = 0.05). Mean creatinine levels were similar in both groups (MoM 93 μmol/L versus MoP 92 μmol/L). Harris hip scores differed only marginally between the MoM and MoP cohorts. Interpretation - This is the longest follow-up of a randomized trial on 28-mm MoM articulations, and although implant survival in the 2 groups was similar, metal ion concentrations remained elevated in the MoM cohort even in the long term.

  20. Metal-on-metal bearings a clinical practicum

    CERN Document Server

    Jones, Lynne C; Greenwald, A Seth

    2014-01-01

    This book addresses the background and significance of factors potentially influencing clinical and biological outcomes of metal-on-metal hip implants. Includes discussion of reported complications including pseudotumors and other lymphocytic-based responses.

  1. Finite element modeling of resurfacing hip prosthesis: estimation of accuracy through experimental validation.

    Science.gov (United States)

    Taddei, Fulvia; Martelli, Saulo; Gill, Harinderjit Singh; Cristofolini, Luca; Viceconti, Marco

    2010-02-01

    Metal-on-metal hip resurfacing is becoming increasingly popular, and a number of new devices have been recently introduced that, in the short term, appear to have satisfactory outcome but many questions are still open on the biomechanics of the resurfaced femur. This could be investigated by means of finite element analysis, but, in order to be effective in discerning potential critical conditions, the accuracy of the models' predictions should be assessed. The major goal of this study was to validate, through a combined experimental-numerical study, a finite element modeling procedure for the simulation of resurfaced femurs. In addition, a preliminary biomechanical analysis of the changes induced in the femoral neck biomechanics by the presence of the device was performed, under a physiologic range of hip joint reaction directions. For this purpose, in vitro tests and a finite element model based on the same specimen were developed using a cadaver femur. The study focused on the Conserve Plus, one of the most common contemporary resurfacing designs. Five loading configurations were identified to correspond to the extremes of physiological directions for the hip joint. The agreement between experimental measurements and numerical predictions was good both in the prediction of the femoral strains (R(2)>0.9), and in the prosthesis micromotions (errorprosthesis, apart from localized strain increments that can be considerable, always predicted near the stem. Low micromotions and contact pressure were predicted, suggesting a good stability of the prosthesis. The model accuracy was good in the prediction of the femoral strains and moderately good in the prediction of the bone-prosthesis micromovements. Although the investigated loading conditions were not completely physiological, the preliminary biomechanical analysis showed relatively small changes for the proximal femur after implantation. This validated model can support realistic simulations to examine physiological

  2. [Choice of hip prosthesis in patients younger than 50 years

    NARCIS (Netherlands)

    Schreurs, B.W.; Busch, V.J.; Veth, R.P.H.

    2007-01-01

    There is no agreement about the most ideal type of hip prosthesis to be used in patients younger than 50 years. The most commonly used hip prostheses in patients younger than 50 years are uncemented or resurfacing prostheses and to a lesser extent cemented prostheses. A good result of a hip

  3. Impact of hip prosthesis on dose distribution of pelvic radiotherapy

    International Nuclear Information System (INIS)

    Ren Jiangping; Zhang Songfang; Zhu Qibao; Guo Jianxin; Zha Yuanzi

    2011-01-01

    Objective: To study the scattering effect of Co-Cr-Mo hip prosthesis which was high Z material for patients undergoing pelvic irradiation. Methods: The hip prosthesis was set in water phantom (30 cm x 30 cm x 30 cm), determining points were chosen on the entrance side of both 6 MV and 10 MV beams at the distance of 0.5 cm, 1.0 cm, 2.0 cm to the hip prosthesis, and also on the exit side of both 6 MV and 10 MV beams at the distance of 3.0 cm, 5.0 cm, 7.0 cm to the hip prostheses. Dose behind the hip prosthesis at depths of 5.0 cm and 10.0 cm for 6 MV and 10 MV beams are also measured. Results: The dose deviation on the beams' entrance side is between 0 to 5.0%, the backscatter effect was more obviously with the higher energy beam. The dose deviation on the beams' exit side was between 21.6%-30.8%. With the same field size and depth, dose deviation becomes smaller when the beam energy was higher; while with the same energy and depth, dose deviation becomes smaller when the field size was bigger. Dose profiles behind the head of the hip prosthesis indicate obvious attenuation of the beam. Conclusions: Beam arrangements that avoid the prosthesis should be considered first or we should at least reduce the weight of the beam that pass through the prosthesis. (authors)

  4. 21 CFR 888.3390 - Hip joint femoral (hemi-hip) metal/polymer cemented or uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented or uncemented prosthesis. 888.3390 Section 888.3390 Food and Drugs FOOD AND DRUG ADMINISTRATION... § 888.3390 Hip joint femoral (hemi-hip) metal/polymer cemented or uncemented prosthesis. (a) Identification. A hip joint femoral (hemi-hip) metal/polymer cemented or uncemented prosthesis is a two-part...

  5. 21 CFR 888.3380 - Hip joint femoral (hemi-hip) trunnion-bearing metal/polyacetal cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... metal/polyacetal cemented prosthesis. 888.3380 Section 888.3380 Food and Drugs FOOD AND DRUG... Devices § 888.3380 Hip joint femoral (hemi-hip) trunnion-bearing metal/polyacetal cemented prosthesis. (a) Identification. A hip joint femoral (hemi-hip) trunnion-bearing metal/polyacetal cemented prosthesis is a two...

  6. [Are the cobalt hip prosthesis dangerous?].

    Science.gov (United States)

    Mistretta, Virginie; Kurth, William; Charlier, Corinne

    The placement of a hip prosthesis is one of the most common orthopedic surgical procedures. Some implants contain metal and are therefore capable of releasing metal particles like cobalt in patients who wear metal prostheses. Cobalt can be responsible of local toxicity (including metallosis, hypersensitivity reaction, and benign tumor) or systemic toxicity (including cardiomyopathy, polycythemia, hypothyroidism, and neurological disorders). To monitor potential toxicity of metal hip prostheses, an annual monitoring of patients implanted is recommended and includes clinical examination, radiological examination and blood cobalt determination. The cobalt concentration in blood allows to estimate the risk of toxicity and to evaluate the performance of the implant. The currently recommended threshold value is equal to 7 µg of cobalt per liter of blood. Our study, conducted on 251 patients over a period of 4 years, has shown that the cobalt concentration average was 2.51 µg/l in blood, with 51 patients having a cobaltemia higher than the threshold of 7 µg/l. © 2016 médecine/sciences – Inserm.

  7. Disassembly and Dislocation of a Bipolar Hip Prosthesis

    Directory of Open Access Journals (Sweden)

    Hsieh-Hsing Lee

    2008-01-01

    Full Text Available Dislocation of a hip prosthesis is a common complication. In usual cases of hip prosthesis dislocation, the prosthetic femoral head comes out from either the natural acetabular cavity in a bipolar hemiarthroplasty or the prosthetic acetabulum in a total hip arthroplasty. Only a few cases of bipolar hip prosthesis dislocation due to dissociation between the polyethylene and inner head of the prosthesis have been reported. We describe a rare case of disassembly of the inner head from the bipolar outer prosthesis in an osteoarthritic acetabulum. A 72-year-old woman had undergone bipolar hemiarthroplasty due to fracture of the left femoral neck about 10 years previously. Recently, she sustained an injury after falling from a chair, and examinations revealed an unusual disassembly−dislocation of the bipolar hip prosthesis. We classified this failure in our patient as a type II failure, representing extreme varus position of the outer head in the acetabulum, dislocation of the inner head from the outer head, and a detached locking ring around the stem neck. This mechanism of failure as shown in our patient rarely occurs in the bipolar prosthesis of the self-centering system. Osteoarthritic change of the acetabulum would place the outer head in the varus position, increasing wear on the beveled rim by impinging the femoral stem neck and causing dislodgment of the inner locking ring and consequent disassembly−dislocation of the inner head.

  8. Comparison of metal ion concentrations and implant survival after total hip arthroplasty with metal-on-metal versus metal-on-polyethylene articulations

    OpenAIRE

    Dahlstrand, Henrik; Stark, André; Wick, Marius C; Anissian, Lucas; Hailer, Nils P; Weiss, Rüdiger J

    2017-01-01

    Background and purpose Large metal-on-metal (MoM) articulations are associated with metal wear and corrosion, leading to increased metal ion concentrations and unacceptable revision rates. There are few comparative studies of 28-mm MoM articulations with conventional metal-on-polyethylene (MoP) couplings. We present a long-term follow-up of a randomized controlled trial comparing MoM versus MoP 28-mm articulations, focused on metal ions and implant survival. Patients and methods 85 patients w...

  9. The Effectiveness of Blood Metal Ions in Identifying Patients with Unilateral Birmingham Hip Resurfacing and Corail-Pinnacle Metal-on-Metal Hip Implants at Risk of Adverse Reactions to Metal Debris.

    Science.gov (United States)

    Matharu, Gulraj S; Berryman, Fiona; Brash, Lesley; Pynsent, Paul B; Treacy, Ronan B C; Dunlop, David J

    2016-04-20

    We investigated whether blood metal ions could effectively identify patients with metal-on-metal hip implants with two common designs (Birmingham Hip Resurfacing [BHR] and Corail-Pinnacle) who were at risk of adverse reactions to metal debris. This single-center, prospective study involved 598 patients with unilateral hip implants (309 patients with the BHR implant and 289 patients with the Corail-Pinnacle implant) undergoing whole blood metal ion sampling at a mean time of 6.9 years. Patients were classified into two groups, one that had adverse reactions to metal debris (those who had to undergo revision for adverse reactions to metal debris or those with adverse reactions to metal debris on imaging; n = 46) and one that did not (n = 552). Three metal ion parameters (cobalt, chromium, and cobalt-chromium ratio) were compared between groups. Optimal metal ion thresholds for identifying patients with adverse reactions to metal debris were determined using receiver operating characteristic analysis. All ion parameters were significantly higher (p adverse reactions to metal debris compared with those who did not. Cobalt maximized the area under the curve for patients with the BHR implant (90.5%) and those with the Corail-Pinnacle implant (79.6%). For patients with the BHR implant, the area under the curve for cobalt was significantly greater than that for the cobalt-chromium ratio (p = 0.0005), but it was not significantly greater than that for chromium (p = 0.8483). For the patients with the Corail-Pinnacle implant, the area under the curve for cobalt was significantly greater than that for chromium (p = 0.0004), but it was similar to that for the cobalt-chromium ratio (p = 0.8139). Optimal blood metal ion thresholds for identifying adverse reactions to metal debris varied between the two different implants. When using cobalt, the optimal threshold for identifying adverse reactions to metal debris was 2.15 μg/L for the BHR group and 3.57 μg/L for the Corail

  10. Increased metal allergy in patients with failed metal-on-metal hip arthroplasty and peri-implant T-lymphocytic inflammation.

    Science.gov (United States)

    Thomas, P; Braathen, L R; Dörig, M; Auböck, J; Nestle, F; Werfel, T; Willert, H G

    2009-08-01

    In 16 patients with revised metal-on-metal arthroplasty and peri-implant lymphocytic inflammation, we verified the role of metal hypersensitivity by patch testing (PT) and lymphocyte transformation test (LTT). In the 16 patients with lymphocyte dominated periprosthetic inflammation, allergy history was obtained by a questionnaire, specific serum IgE to aeroallergens was measured to assess atopy, PT to standard and metal series was performed and metal sensitivity was further assessed by LTT using blood mononuclear cells. Revision surgery was performed because of pain (8/16), osteolysis (4/16), dislocation (3/16) and loosening of the stem (1/16). Histological examination showed perivascular infiltrates of T lymphocytes, high endothelial venules, fibrin exudation and accumulation of macrophages with drop-like inclusions. Five patients had a history of cutaneous metal allergy and atopy was found in 25% of the patients. In 13/16 patients (81%), systemic metal sensitivity was found based on PT and/or LTT. Patch test reactions were seen in 11/16 patients (69%; partly multiple reactions/patient): 7/16 to Cobalt (Co), 7/16 to Chromium (Cr), 4/16 to Nickel (Ni), and one each to Molybdenum (Mo) and Manganese (Mn). Ten of 16 patients (62%) showed enhanced LTT reactivity to metals: 7/16 to Ni, 7/16 to Co, 5/16 to Cr, 5/16 to Mo and 4/16 to Mn. The lymphocyte dominated peri-implant inflammation may well reflect an allergic hyper-reactivity in these patients, given the high rate of concomitantly found metal allergy. Despite the overall incidence of metal implant allergy being low, allergic reactions should be included as differential diagnosis in failed metal-on-metal arthroplasty.

  11. A new approach towards hip-prosthesis design.

    Science.gov (United States)

    Huggler, A H; Jacob, H A

    1980-01-01

    A new femoral prosthesis with a stemless design, different from conventional types, has been conceived in an effort to preserve the physiological stress distribution in magnitude and direction within the living bone as far as possible. The most important feature is that the hip joint forces are transmitted directly to the cortical bone of the resected femoral neck by means of a thrust plate, which maintains the physiological stress an the proximal end of the femur. The prosthesis, the instruments required for its implantation and the surgical technique are described in detail. Up to now, 3 patients have received this new prosthesis.

  12. Dosimetric influence of hip prosthesis during radiotherapeutic treatment

    International Nuclear Information System (INIS)

    Gschwind, R.; Buffard, E.; Masset, H.; Makovicka, L.; David, C.; David, C.; Buffard, E.

    2008-01-01

    As the population become aged, many patients with hip prosthesis are treated for a pelvic cancer. The recommended ballistic must avoid to pass in the prosthesis, but sometimes it is inevitable. So it is essential to quantify with accuracy the dose modifications linked to the presence of metallic implant. The aim of this study is to analyze by Monte Carlo method these modifications in simple and complex models (anthropomorphic phantom) which take into account the geometry and the composition of the prosthesis and its coatings. Then, this methodology was used to study the behaviour of a treatment planning system in theses extreme conditions. (authors)

  13. Are Females at Greater Risk for Revision Surgery After Hip Resurfacing Arthroplasty With the Articular Surface Replacement Prosthesis?

    Science.gov (United States)

    Donahue, Gabrielle S; Lindgren, Viktor; Galea, Vincent P; Madanat, Rami; Muratoglu, Orhun; Malchau, Henrik

    2016-10-01

    associated with implant survival, using any revision as the end point, and presence of adverse local tissue reaction. In patients who had unilateral surgery, the only variable found to be associated with revision surgery was HHS (hazard ratio [HR], 0.96; 95% CI, 0.94-0.97; p hip resurfacing arthroplasty with implantation of the ASR(TM) prosthesis should be followed with equal vigilance as both are at similar risk of revision surgery and adverse local tissue reaction. Metal ion levels and HHS should be obtained at followup to monitor for risk of revision and as a screening tool for MRI. Further research is necessary to evaluate if these relationships persist in patients with other metal-on-metal prostheses. Level II, therapeutic study.

  14. Hip arthroplasty. Part 1: prosthesis terminology and classification

    International Nuclear Information System (INIS)

    Pluot, E.; Davis, E.T.; Revell, M.; Davies, A.M.; James, S.L.J.

    2009-01-01

    Hip arthroplasty is an extremely common orthopaedic procedure and there is a wide array of implants that are in current use in the UK. The follow-up of patients who have undergone insertion of a hip prosthesis is shifting from a consultant-lead hospital service towards primary care. As this change in patient care continues it becomes increasingly important that an accurate description of the radiographic features is communicated to the primary-care practitioner so appropriate specialist input can be triggered. This review focuses on the terminology and classification of hip prostheses. This acts as a precursor for Part 2 of this series, which describes the normal and abnormal radiographic findings following hip prosthesis insertion.

  15. Key Parameters Evaluation for Hip Prosthesis with Finite Element Analysis

    Science.gov (United States)

    Guo, Hongqiang; Li, Dichen; Lian, Qin; Li, Xiang; Jin, Zhongmin

    2007-09-01

    Stem length and cross section are two key parameters that influence the stability and longevity of metallic hip prosthesis in the total hip arthroplasty (THA). In order to assess their influence to the stress and fatigue behavior of hip prosthesis, a series model of hip prosthesis with round-shaped or drum-shaped cross section, and with different stem lengths were created. These models were analyzed under both static and dynamic loading conditions with finite element analysis, and dynamic loading represents normal walking was used in the dynamic analysis. The stress on the metallic stem, cement, and adjacent bone were got, micromotion on the cement-metal interface were got too. Safety factors for fatigue life of the hip prothesis were calculated based on data obtained from dynamic analysis. Static analysis shows that drum-shaped cross section can decrease the displacement of the stem, that stress on drum-shaped stem focus on the corner of the femoral neck and the distal part of hip prosthesis, whereas the stress on the round-shaped stem distributes evenly over most part of the stem, and maximum stress on stem prosthesis fluctuates with stem length bottoming out at stem length range from 80 mm to 110 mm, that drum-shaped stems with drum height 8 mm generate more stress at the distal part of stem than drum-shaped stems with drum height 10 mm and round stems do. Dynamic and fatigue analysis shows that drum-shaped stem with drum height 10 mm and stem length 90 mm has the greatest safety factor therefore long fatigue life.

  16. Strain-stress analysis of surface prosthesis of hip joint

    Czech Academy of Sciences Publication Activity Database

    Návrat, Tomáš; Fuis, Vladimír; Florian, Z.; Hlavoň, Pavel

    2007-01-01

    Roč. 40, č. 2 (2007), S559-S559 ISSN 0021-9290. [ISB 2007. Taipei, 01.07.2007-05.07.2007] R&D Projects: GA ČR GA101/05/0136 Institutional research plan: CEZ:AV0Z20760514 Keywords : surface prosthesis * hip joint * FEM Subject RIV: BO - Biophysics Impact factor: 2.897, year: 2007

  17. Postoperative migration of short stem prosthesis of the hip joint.

    Science.gov (United States)

    Kamiński, Paweł; Szmyd, Jakub; Ambroży, Jarosław; Jurek, Wojciech

    2015-01-01

    Hip replacement surgery is a popular procedure that provides predictable, long-lasting and good effects. The use of short stem prostheses helps preserve an intact medullary cavity and proximal diaphysis. It has been demonstrated that the use of short stem prostheses leads to better clinical results compared to standard stem prostheses. The study aimed to assess the migration of the stem of the Proxima hip prosthesis. Migration was defined as a change in the angle of stem position towards a varus deformity. The study involved 164 patients (83 women, 81 men) who underwent hip replacement surgery with a total of 185 Proxima prostheses in the Cracow Rehabilitation Centre between 2007 and 2012. Radiographic analysis included a series of three radiographs obtained for each patient on Day 0 and after 6 and 12 months. Stem migration towards a varus deformity was reported during the follow-up period. There was a correlation between the change in the angle of varus prosthesis alignment and the length of follow-up. The mean change of the varus angle was 8.21° after 12 months. There was a statistically significant difference in the angle of the varus prosthesis alignment between the sexes. After 12 months the total change was 6.82° in women and 9.65° in men. There was no significant correlation between a patient's BMI, age, the total length of the neck of the implant and the progression of the angle of varus prosthesis alignment. 1. The greatest displacement of the Proxima short stem implant towards a varus deformity is seen within the first 6 months following implantation. 2. The change of the angle of varus prosthesis alignment depends on the initial positioning of the prosthesis and the sex of the patient. 3. The change of the angle of varus prosthesis alignment is independent from the patient's age and BMI.

  18. Do hip prosthesis related infection codes in administrative discharge registers correctly classify periprosthetic hip joint infection?

    DEFF Research Database (Denmark)

    Lange, Jeppe; Pedersen, Alma B; Troelsen, Anders

    2015-01-01

    ) periprosthetic hip joint infection diagnosis code in the Danish National Patient Register. METHODS: Patients were identified with an ICD-10 discharge diagnosis code of T84.5 ("Infection and inflammatory reaction due to internal joint prosthesis") in association with hip-joint associated surgical procedure codes...

  19. 21 CFR 888.3310 - Hip joint metal/polymer constrained cemented or uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... uncemented prosthesis. 888.3310 Section 888.3310 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Hip joint metal/polymer constrained cemented or uncemented prosthesis. (a) Identification. A hip joint metal/polymer constrained cemented or uncemented prosthesis is a device intended to be implanted to...

  20. 21 CFR 888.3340 - Hip joint metal/composite semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3340 Section 888.3340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Hip joint metal/composite semi-constrained cemented prosthesis. (a) Identification. A hip joint metal/composite semi-constrained cemented prosthesis is a two-part device intended to be implanted to replace a...

  1. 21 CFR 888.3350 - Hip joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3350 Section 888.3350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/polymer semi-constrained cemented prosthesis. (a) Identification. A hip joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a hip joint. The device limits...

  2. 21 CFR 888.3300 - Hip joint metal constrained cemented or uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3300 Section 888.3300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal constrained cemented or uncemented prosthesis. (a) Identification. A hip joint metal constrained cemented or uncemented prosthesis is a device intended to be implanted to replace a hip joint. The device...

  3. Pseudotumour formation and subsequent resolution in metal-on-metal total hip arthroplasty following revision: Instructional review and an illustrative case report with revision using a dual mobility design.

    Science.gov (United States)

    Sassoon, A A; Barrack, R L

    2016-06-01

    The use of large-diameter metal-on-metal (MoM) components in total hip arthroplasty (THA) is associated with an increased risk of early failure due to adverse local tissue reaction to metal debris (ARMD) in response to the release of metal ions from the bearing couple and/or head-neck taper corrosion. The aim of this paper was to present a review of the incidence and natural history of ARMD and the forms of treatment, with a focus on the need for and extent of resection or debulking of the pseudotumour. An illustrative case report is presented of a patient with an intra-pelvic pseudotumour associated with a large diameter MoM THA, which was treated successfully with revision of the bearing surface to a dual mobility couple and retention of the well-fixed acetabular and femoral components. The pseudotumour was left in situ Resolution of the intra-pelvic mass and normalisation of metal ion levels was observed seven months post-operatively. Cite this article: Bone Joint J 2016;98-B:736-40. ©2016 The British Editorial Society of Bone & Joint Surgery.

  4. The Infection Rate of Metal-on-Metal Total Hip Replacement Is Higher When Compared to Other Bearing Surfaces as Documented by the Australian Orthopaedic Association National Joint Replacement Registry.

    Science.gov (United States)

    Huang, Phil; Lyons, Matt; O'Sullivan, Michael

    2018-02-01

    Despite the well-documented decline in the use of metal-on-metal (MoM) implants over the last decade, there are still controversies regarding whether all MoM implants are created equally. Complications such as elevated serum metal ion levels, aseptic lymphocyte-dominated vasculitis-associated lesion (ALVAL) and pseudotumours have all been well documented, but recent studies suggest increased risk of infection with MoM bearing surfaces. Most of these studies however have small patient numbers. The purpose of this study was to examine the cumulative incidence of revision for infection of MoM bearing surfaces in primary hip arthroplasty at a national and single-surgeon level. Data was collected from the Australian Orthopaedic Association National Joint Replacement Registry, which contains over 98% of all arthroplasties performed in Australia since 2001. The cumulative incidence of revision for infection was extracted at a national level and single-surgeon level. Two hundred seventy-six thousand eight hundred seventy-eight subjects were documented in the Australian registry. The 10-year cumulative percent revision for infection of MoM bearing surfaces in primary total hip replacement (THR) was 2.5% at a national level, compared to 0.8% for other bearing surfaces. The senior author contributed 1755 subjects with 7-year follow-up and a cumulative percent revision for infection of MoM bearing surfaces in primary THR of 36.9%, compared to 2.0% for other bearing surfaces. The cumulative percent of revision of MoM bearing surfaces is higher compared to other bearing surfaces; this is especially pronounced in cumulative percent of revision for infection. There was a higher cumulative percent of revision for infection in MoM bearings surfaces (in particular, large-head MoM) compared to other bearing surfaces at both the national and individual-surgeon level.

  5. Automated estimation of hip prosthesis migration: a feasibility study

    Science.gov (United States)

    Vandemeulebroucke, Jef; Deklerck, Rudi; Temmermans, Frederik; Van Gompel, Gert; Buls, Nico; Scheerlinck, Thierry; de Mey, Johan

    2013-09-01

    A common complication associated with hip arthoplasty is prosthesis migration, and for most cemented components a migration greater than 0.85 mm within the first six months after surgery, are an indicator for prosthesis failure. Currently, prosthesis migration is evaluated using X-ray images, which can only reliably estimate migrations larger than 5 mm. We propose an automated method for estimating prosthesis migration more accurately, using CT images and image registration techniques. We report on the results obtained using an experimental set-up, in which a metal prosthesis can be translated and rotated with respect to a cadaver femur, over distances and angles applied using a combination of positioning stages. Images are first preprocessed to reduce artefacts. Bone and prosthesis are extracted using consecutive thresholding and morphological operations. Two registrations are performed, one aligning the bones and the other aligning the prostheses. The migration is estimated as the difference between the found transformations. We use a robust, multi-resolution, stochastic optimization approach, and compare the mean squared intensity differences (MS) to mutual information (MI). 30 high-resolution helical CT scans were acquired for prosthesis translations ranging from 0.05 mm to 4 mm, and rotations ranging from 0.3° to 3° . For the translations, the mean 3D registration error was found to be 0.22 mm for MS, and 0.15 mm for MI. For the rotations, the standard deviation of the estimation error was 0.18° for MS, and 0.08° for MI. The results show that the proposed approach is feasible and that clinically acceptable accuracies can be obtained. Clinical validation studies on patient images will now be undertaken.

  6. Revision hip arthroplasty by Waldemar Link custom-made total hip prosthesis

    Directory of Open Access Journals (Sweden)

    Medenica Ivica

    2010-01-01

    Full Text Available Background. The number of patients undergoing hip arthroplasty revision is constantly growing. Especially, complex problem is extensive loss of bone stock and pelvic discontinuity that requires reconstruction. Case report. The paper presented a 50-year old patient, who ten years ago underwent a total cement artrhroplasty of the left hip. A year after the primary operation the patient had difficulties in walking without crutches. Problems intensified in the last five years, the patient had severe pain, totally limited movement in the left hip and could not walk at all. Radiographically, we found loose femoral component, massive loss of bone stock of proximal femur, acetabular protrusion and a consequent pelvic discontinuity. Clinically, a completely disfunctional left hip joint was registered (Harris hip score - 7.1. We performed total rearthroplasty by a custom- made Waldemar Link total hip prosthesis with acetabular antiprotrusio cage and compensation of bone defects with a graft from the bone bank. A year after the operation, we found clinically an extreme improvement in Harris hip score - 87.8. Radiographically, we found stability of implanted components, a complete graft integration and bone bridging across the site of pelvic discontinuity. Conclusion. Pelvic discontinuity and massive loss of proximal femoral bone stock is a challenging and complex entity. Conventional prostheses cannot provide an adequate fixation and stability of the hip. Application of custom-made prosthesis (measured specifically for a patient and additional alografting bone defects is a good method in revision surgery after unsuccessful hip arthroplasty with extensive bone defects.

  7. Biomechanical comparison of newly designed stemless prosthesis and conventional hip prosthesis--an experimental study.

    Science.gov (United States)

    Tai, Ching-Lung; Lee, Mel S; Chen, Weng-Pin; Hsieh, Pang-Hsin; Lee, Po-Chen; Shih, Chun-Hsiung

    2005-01-01

    Local bone loss after implantation of traditional stem-type prostheses remains an unsolved problem during the long-term application of total hip replacement. The stress shielding effect and osteolysis were thought to be the two main factors that result in local bone loss after prosthesis implantation. A newly designed stemless cervico-trochanteric (C-T) prosthesis was thus developed to reduce stress shielding and osteolysis caused by the implantation of conventional stem-type prosthesis. Eight synthetic femora were implanted with C-T and porous coated anatomic (PCA) prostheses. Under 2,000-Newton load, the surface strains of proximal femora were compared between the intact, PCA press-fit femora and the C-T implanted femora with three different fixation modes: two-screw fixation, three-screw fixation, and three-screw combined with cement fixation. The results revealed that stress shielding in the C-T implanted femora was significantly eliminated compared to that of the PCA implanted femora (p0.1). The C-T implanted femur has more physiological strain distribution. Moreover, from the C-T prosthetic characteristic design, the localized osteolysis would be also reduced due to the overall coverage of neck-trochanteric area. The newly designed C-T prosthesis may be a useful alternative to the traditional stem-type prosthesis in the future.

  8. Gait assessment in patients with thrust plate prosthesis and intramedullary stemmed prosthesis implanted to each hip.

    Science.gov (United States)

    Angin, Salih; Karatosun, Vasfi; Unver, Bayram; Gunal, Izge

    2007-02-01

    There has not been any study regarding comparative gait analysis in patients with intramedullary stemmed prosthesis (ISP) and thrust plate prosthesis (TPP) implanted to each hip. Four patients (three females and one male) who had undergone operation due to coxarthrosis were selected. The mean age was 60.5 (37-78) years. TPP and ISP had been implanted to the left and right hip, respectively, in three patients, and one patient received TPP to the right and ISP to the left hip. Gait was analyzed with a BTS Elite System consisting six cameras and two Kistler force plates using Helen Hayes marker set to assess the gait parameters. The clinical outcome was also evaluated according to Harris hip score (HHS). The average HHS was 95.0 (82-100) points after a mean follow-up of 45.0 (30-50) months for TPP and 94.5 (80-100) points after a follow-up of 60.0 (14-122) months for ISP. Neither of the HHS scores and follow-up time nor gait parameters obtained from the TPP-implanted side were statistically different when compared to those of the ISP-implanted side. TPP and ISP as the implants with their own biomechanical specifications did not produce any remarkable difference in gait.

  9. Functional rehabilitation after total hip arthroplasty with uncemented prosthesis

    Directory of Open Access Journals (Sweden)

    Nicolae-Bogdan Negru-Aman

    2011-12-01

    Full Text Available Arthritis is a disease that acts irreversibly on joint surfaces with significant consequences especially in the third quarter of life. About 7% of our population is affected by arthritis localized at a certain level and stage of development, and this percentage is expected to reach a much higher value in future years. Aim: The aim of this study is to propose a rehabilitation program for functional recovery after total hip arthroplasty and a set of recommendations for post surgery period. Material and methods: There were included 13 subjects (10 female and 3 male aged between 51 and 78 years old, ready for total hip arthroplasty with uncemented prosthesis. The subjects were selected in Orthopaedics and Traumatology department of Military Clinical Emergency Hospital ”Dr. Victor Popescu” Timisoara. The evaluations regarding programs’ efficiency were made using 3 questionnaires (Oxford Hip Score, Harris Hip Score, Outcome Hip Score and goniometry. The subjects were tested initially before the surgery and 3 times after (at one month, at 3 months and at 6 months. Results: The results showed a remarcable increase for the scores of majority, in both questionnaire and goniometry values. Conclusions: functional rehabilitation exercises proved to be particularly important in regaining independence, control of the prosthetic leg, pain reduction and functional and social reintegration.

  10. False-positive indium-111 labeled leukocyte scintigram in a patient with a painful hip prosthesis

    International Nuclear Information System (INIS)

    Feldman, N.; Makler, P.T. Jr.; Alavi, A.

    1986-01-01

    A Tronzo hip prosthesis is designed to elicit an inflammatory reaction in order to promote prosthesis stability. A three-phased bone scan and Ga-67 imaging in conjunction with physical examination and laboratory findings failed to demonstrate evidence for osteomyelitis in a patient with a painful hip prosthesis, in whom images obtained with In-111-labeled leukocytes were positive. This observation demonstrated that the interpretation of the latter technique in demonstrating inflammation can cause a false impression of an infectious process

  11. SYSTEM FOR IN VITRO PRIMARY STABILITY ANALYZIS OF CEMENTED HIP PROSTHESIS

    OpenAIRE

    Corneliu Druga

    2014-01-01

    This paper presents a simple embodiment of the system that can be used for the primary stability analysis of the cemented hip prosthesis. The proposed variant is based on experimental test stand for hip prostheses (in terms of tribology) found in Biomechatronics Lab of the Product Design and Environment Faculty. For this study three aspects are important: counting the number of cycles that it performs cemented hip prosthesis and the time when the first microdisplacements ...

  12. Femoral hip prosthesis design for Thais using multi-objective shape optimization

    International Nuclear Information System (INIS)

    Virulsri, Chanyaphan; Tangpornprasert, Pairat; Romtrairat, Parineak

    2015-01-01

    Highlights: • A multi-objective shape optimization was proposed to design hip prosthesis for Thais. • The prosthesis design was optimized in terms of safety of both cement and prosthesis. • The objective functions used the Soderberg fatigue strength formulations. • Safety factors of the cement and prosthesis are 1.200 and 1.109 respectively. • The newly designed prosthesis also fits well with chosen small-sized Thai femurs. - Abstract: The long-term success of Total Hip Arthroplasty (THA) depends largely on how well the prosthetic components fit the bones. The majority of cemented femoral hip prosthesis failures are due to aseptic loosening, which is possibly caused by cracking of the cement mantle. The strength of cement components is a function of cement mantles having adequate thickness. Since the size and shape of cemented femoral hip prostheses used in Thailand are based on designs for a Caucasian population, they do not properly conform to most Thai patients’ physical requirements. For these reasons, prostheses designed specifically for Thai patients must consider the longevity and functionality of both cement and prosthesis. The objective of this study was to discover a new design for femoral hip prostheses which is not only optimal and safe in terms of both cement and prosthesis, but also fits the selected Thai femur. This study used a small-sized Thai femoral model as a reference model for a new design. Biocompatible stainless steel 316L (SS316L) and polymethylmethacrylate (PMMA) were selected as raw materials for the prosthesis and bone cement respectively. A multi-objective shape optimization program, which is an interface between optimization C program named NSGA-II and a finite element program named ANSYS, was used to optimize longevity of femoral hip prostheses by varying shape parameters at assigned cross-sections of the selected geometry. Maximum walking loads of sixty-kilograms were applied to a finite element model for stress and

  13. Supracondylar correction osteotomy to prevent repetitive posterior dislocation of a hip prosthesis

    NARCIS (Netherlands)

    Haverkamp, D.; Marti, R. K.

    2008-01-01

    Recurrent dislocation of a total hip prosthesis can be a challenging and often disappointing problem. This case report describes a 78-year-old woman who had recurrent posterior dislocations of a revision total hip replacement (THR) that occurred on flexion and internal rotation of the hip. The

  14. Evaluation of possible hip prosthesis infection with In-111 leukocyte scintigraphy

    International Nuclear Information System (INIS)

    Noto, R.B.; Alavi, A.; Star, A.M.; Cuckler, J.M.; Eisenberg, B.

    1987-01-01

    To evaluate the utility of In-111 leukocyte scintigraphy in patients with possible hip prosthesis infection, the authors retrospectively reviewed 44 such scans without clinical history. The results of In-111 leukocyte scans were compared with intraoperative cultures obtained at the time of prosthesis revision in 34 patients, with hip aspirates and/or clinical follow-up obtained in the remaining ten patients. This comparison yielded a 71% sensitivity, 78% specificity, and 77% overall accuracy. They conclude that In-111 leukocyte scans can be helpful in the evaluation of suspected hip prosthesis infection, but they are not as accurate as has been previously reported elsewhere

  15. Hip Implant Systems

    Science.gov (United States)

    ... Orthopaedic Surgeons Information about Soft Tissue Imaging and Metal Ion Testing Information for All Health Care Professionals who Provide Treatment to Patients with a Metal-on-Metal Hip Implant Metal-on-Metal Hip ...

  16. Hip prosthesis in sitting posture for bilateral transfemoral amputee after burn injury: a case report.

    Science.gov (United States)

    Shimizu, Yukiyo; Mutsuzaki, Hirotaka; Maezawa, Takayuki; Idei, Yuji; Takao, Kazuya; Takeuchi, Ryoko; Onishi, Shinzo; Hada, Yasushi; Yamazaki, Masashi; Wadano, Yasuyoshi

    2017-10-01

    To overcome the challenges of rehabilitation of bilateral transfemoral amputees, we developed a novel "hip prosthesis in the sitting posture." Case Description and Methods: A 64-year-old male bilateral transfemoral amputee was transferred for rehabilitation 4 months following a burn injury. His wounds remained unhealed for 20 months; thus, he was unable to participate in standing training with the standard prosthetic sockets. Hip prosthesis in the sitting posture has very little friction between the sockets and residual limbs, which facilitated our patient to begin standing and walking exercises. Findings and Outcomes: The patient's refractory wounds healed 1 month after initiating exercises using hip prosthesis in the sitting posture, and he could begin rehabilitation with the standard prostheses. Hip prosthesis in the sitting posture enabled a bilateral transfemoral amputee with unhealed residual limbs to stand, walk, and begin balance training. Hip prosthesis in the sitting posture is an effective temporary prosthesis to prevent disuse until wounds are healed and to continue rehabilitation with standard prostheses. Clinical relevance Hip prosthesis in the sitting posture is useful for bilateral transfemoral amputees with unhealed residual limbs after burn injuries to prevent disuse and maintain motivation for walking.

  17. 21 CFR 888.3358 - Hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... porous-coated uncemented prosthesis. 888.3358 Section 888.3358 Food and Drugs FOOD AND DRUG... Devices § 888.3358 Hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis. (a) Identification. A hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis is a device...

  18. 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 device...

  19. 21 CFR 888.3353 - Hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented or nonporous uncemented prosthesis. 888.3353 Section 888.3353 Food and Drugs FOOD AND DRUG... prosthesis. (a) Identification. A hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis is a device intended to be implanted to replace a hip joint. This device limits...

  20. 21 CFR 888.3320 - Hip joint metal/metal semi-constrained, with a cemented acetabular component, prosthesis.

    Science.gov (United States)

    2010-04-01

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

  1. [Total knee and hip prosthesis: variables associated with costs].

    Science.gov (United States)

    Herrera-Espiñeira, Carmen; Escobar, Antonio; Navarro-Espigares, José Luis; Castillo, Juan de Dios Lunadel; García-Pérez, Lidia; Godoy-Montijano, Amparo

    2013-01-01

    The elevated prevalence of osteoarthritis in Western countries, the high costs of hip and knee arthroplasty, and the wide variations in the clinical practice have generated considerable interest in comparing the associated costs before and after surgery. To determine the influence of a number of variables on the costs of total knee and hip arthroplasty surgery during the hospital stay and during the one-year post-discharge. A prospective multi-center study was performed in 15 hospitals from three Spanish regions. Relationships between the independent variables and the costs of hospital stay and postdischarge follow-up were analyzed by using multilevel models in which the "hospital" variable was used to group cases. Independent variables were: age, sex, body mass index, preoperative quality of life (SF-12, EQ-5 and Womac questionnaires), surgery (hip/knee), Charlson Index, general and local complications, number of beds and economic-institutional dependency of the hospital, the autonomous region to which it belongs, and the presence of a caregiver. The cost of hospital stay, excluding the cost of the prosthesis, was 4,734 Euros, and the post-discharge cost was 554 Euros. With regard to hospital stay costs, the variance among hospitals explained 44-46% of the total variance among the patients. With regard to the post-discharge costs, the variability among hospitals explained 7-9% of the variance among the patients. There is considerable potential for reducing the hospital stay costs of these patients, given that more than 44% of the observed variability was not determined by the clinical conditions of the patients but rather by the behavior of the hospitals.

  2. Phantom studies of triple photon absorptiometry and bone mineral measurement at a hip prosthesis

    International Nuclear Information System (INIS)

    Farrell, T.J.; Webber, C.E.

    1992-01-01

    The feasibility of using triple photon absorptiometry (TPA) for the measurement of bone mineral mass about a hip prosthesis was examined. A theoretical expression describing the variance of TPA measurements was verified using a triple photon source and phantom materials which simulate the soft tissue-bone mineral-metal prosthesis system. The expression for the variance was used to determine an optimized set of photon energies. It was shown that a precision of 3% could be obtained for reasonable measurement times using this optimized set of energies and that TPA should be a feasible approach for measurement of bone mineral about a hip prosthesis. (orig.)

  3. Gene therapy and cement injection for the treatment of hip prosthesis loosening in elderly patients

    NARCIS (Netherlands)

    Poorter, Jolanda de

    2010-01-01

    Approximately one million total hip replacement operations are performed worldwide annually, mostly for osteoarthritis and rheumatoid arthritis. A major complication in total hip arthroplasties is loosening of the prosthesis leading to pain and walking difficulties and a higher risk for dislocations

  4. In-situ electrochemical study of interaction of tribology and corrosion in artificial hip prosthesis simulators.

    Science.gov (United States)

    Yan, Yu; Dowson, Duncan; Neville, Anne

    2013-02-01

    The second generation Metal-on-Metal (MoM) hip replacements have been considered as an alternative to commonly used Polyethylene-on-Metal (PoM) joint prostheses due to polyethylene wear debris induced osteolysis. However, the role of corrosion and the biofilm formed under tribological contact are still not fully understood. Enhanced metal ion concentrations have been reported widely from hair, blood and urine samples of patients who received metal hip replacements and in isolated cases when abnormally high levels have caused adverse local tissue reactions. An understanding of the origin of metal ions is really important in order to design alloys for reduced ion release. Reciprocating pin-on-plate wear tester is a standard instrument to assess the interaction of corrosion and wear. However, more realistic hip simulator can provide a better understanding of tribocorrosion process for hip implants. It is very important to instrument the conventional hip simulator to enable electrochemical measurements. In this study, simple reciprocating pin-on-plate wear tests and hip simulator tests were compared. It was found that metal ions originated from two sources: (a) a depassivation of the contacting surfaces due to tribology (rubbing) and (b) corrosion of nano-sized wear particles generated from the contacting surfaces. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. 21 CFR 888.3410 - Hip joint metal/polymer or ceramic/polymer semiconstrained resurfacing cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... semiconstrained resurfacing cemented prosthesis. 888.3410 Section 888.3410 Food and Drugs FOOD AND DRUG... prosthesis. (a) Identification. A hip joint metal/polymer or ceramic/polymer semi-constrained resurfacing cemented prosthesis is a two-part device intended to be implanted to replace the articulating surfaces of...

  6. Effects of metal-inlay thickness in polyethylene cups with metal-on-metal bearings.

    NARCIS (Netherlands)

    Verdonschot, N.J.J.; Vena, P.; Stolk, J.; Huiskes, R.

    2002-01-01

    A way to prevent polyethylene wear in total hip replacements is to use metal-on-metal bearings. The cup design of these bearings may be a metal inlay in a polyethylene cup. However, these metal inlays are relatively thin and may deform on loading. The purpose of the current study was to determine

  7. Complications Related to Metal-on-Metal Articulation in Trapeziometacarpal Joint Total Joint Arthroplasty

    DEFF Research Database (Denmark)

    Frølich, Christina; Hansen, Torben Bæk

    2015-01-01

    Adverse reactions to metal-on-metal (MoM) prostheses are well known from total hip joint resurfacing arthroplasty with elevated serum chrome or cobalt, pain and pseudo tumor formation. It may, however, also be seen after total joint replacement of the trapeziometacarpal joint using MoM articulation...

  8. EVALUATION AND RANKING OF ARTIFICIAL HIP PROSTHESIS SUPPLIERS BY USING A FUZZY TOPSIS METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Marija Zahar Djordjevic

    2014-06-01

    Full Text Available The aim of this study is to propose a fuzzy multi-criteria decision-making approach (MCDM to evaluate the artificial hip prosthesis suppliers with respect to numerous criteria, simultaneously, taking into account the type of each criteria and its relative importance. The fuzzy of the Technique for Order Preference by Similarity to Ideal Solution (FTOSISis applied in order to rank the artificial hip prosthesis suppliers. The rank is obtained using the process of fuzzy number comparison. Software solution based on suggested method is also presented. A real-life example with real data is presented to clarify the proposed method.

  9. Total Hip Arthroplasty Using the S-ROM-A Prosthesis for Anatomically Difficult Asian Patients

    Directory of Open Access Journals (Sweden)

    Akira Hozumi

    2015-01-01

    Full Text Available Background. The S-ROM-A prosthesis has been designed for the Asian proximal femur with a small deformed shape and narrow canal. In this study, the clinical and radiological results using the S-ROM-A prosthesis for Japanese patients with severe deformity due to dysplasia and excessive posterior pelvic tilt were examined. Methods. 94 hips were followed up for a mean of 55 months, with a mean age at surgery of 61 years. The primary diagnoses were 94 coxarthritis cases, including 51 dysplasia and 37 primary OA, 1 avascular necrosis, 2 traumatic arthritis, and 3 Perthes disease. Thirty-one hips had been treated with osteotomy of the hip joints. Preoperative intramedullary canal shapes were stovepipe in 23 hips, normal in 51 hips, and champagne-flute in 5 hips. The maximum pelvic inclination angle was 56°. Results. The mean JOA score improved from 46 points preoperatively to 80 points at final follow-up. On radiological evaluation of the fixation of the implants according to the Engh classification, 92 (97% hips were classified as “bone ingrown fixation.” Conclusion. In primary THA, using the S-ROM-A prosthesis for Asian patients with proximal femoral deformity, even after osteotomy and with posterior pelvic tilt, provided good short- to midterm results.

  10. Bicentric bipolar hip prosthesis: A radiological study of movement at the interprosthetic joint

    Directory of Open Access Journals (Sweden)

    Anil Kumar Rai

    2011-01-01

    Full Text Available Background: The bipolar hip prostheses after some time functions as a unipolar device. There is a need to change the design of bipolar hip prostheses to make it function as a bipolar device over a prolonged period of time. A bicentric bipolar hip prosthesis was used as an implant for various conditions of the hip. We evaluated the movement of this newly developed prosthesis at the interprosthetic joint radiologically at periodic intervals. Materials and Methods: Fifty two cases were operarted with the Bicentric bipolar prosthesis for indications like fracture neck of femur and various other diseases of the hip and were followed up with serial radiographs at periodic intervals to evaluate, what fraction of the total abduction at the hip was occurring at the interprosthetic joint. Results: In cases of intracapsular fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 33.74% (mean value of all the patients, which fell to 25.66% at 1.5 years. In indications for bipolar hemireplacement other than fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 71.71% (mean value and at 1.5 years it was 67.52%. Conclusion: This study shows the relative preservation of inner bearing movement in the bipolar hip prosthesis with time probably due its refined design. Further refinements are needed to make the prosthesis work better in patients of intracapsular fracture neck femur.

  11. Use of a long distally fixed intramedullary stem to treat a periprosthetic femoral fracture following total hip arthroplasty using a thrust plate hip prosthesis: A case report

    OpenAIRE

    Hatanaka, Hiroyuki; Motomura, Goro; Ikemura, Satoshi; Sonoda, Kazuhiko; Kubo, Yusuke; Utsunomiya, Takeshi; Yamamoto, Takuaki; Nakashima, Yasuharu

    2017-01-01

    Introduction: The thrust plate hip prosthesis (TPP; Zimmer, Winterthur, Switzerland) is a hip prosthesis that is no longer in production. Few reports have focused on periprosthetic fractures following total hip arthroplasty (THA) with the use of a TPP. Presentation of case: We report a 57-year-old woman with a periprosthetic femoral fracture 13 years after THA with the use of a TPP. A plain radiograph showed a displaced subtrochanteric fracture of the right femur just below the distal tip ...

  12. Abductor dysfunction and related sciatic nerve palsy, a new complication of metal-on-metal arthroplasty.

    Science.gov (United States)

    Beaver, Walter B; Fehring, Thomas K

    2012-08-01

    The optimal bearing for use in young patients with hip arthritis remains elusive. Current options include metal-on-cross-linked polyethylene, ceramic-on-cross-linked polyethylene, ceramic on ceramic, and metal on metal. Each of these bearing couples has advantages and disadvantages. Metal-on-metal designs allow the use of large heads that decrease impingement and improve stability. This fact has made this bearing an attractive option for surgeons and patients alike. This case report will illustrate a severe adverse reaction to metal debris with necrosis of soft tissues and subsequent damage to the sciatic nerve. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. [Mid-term effectiveness of total hip arthroplasty with collum femoris preserving prosthesis].

    Science.gov (United States)

    Li, Mingqing; Hu, Yihe; Li, Kanghua; Liao, Qiande; Wen, Ting; Zhong, Da

    2012-08-01

    To discuss the clinical application of total hip arthroplasty (THA) with collum femoris preserving (CFP) prosthesis and to analyze the mid-term effectiveness. Between January 2004 and February 2007, 45 patients (48 hips) underwent THA with CFP prosthesis. There were 29 males (31 hips) and 16 females (17 hips) with an average age of 48.8 years (range, 38-60 years), including 20 left hips, 22 right hips, and 3 bilateral hips. The causes of hip replacement were osteoarthritis (20 cases), avascular necrosis of femoral head (13 cases), dysplasia (4 cases), rheumatoid arthritis (3 cases), posttraumatic osteoarthritis (2 cases), ankylosing spondylitis (2 cases), and Perths disease (1 case). The average disease duration was 6.1 years (range, 2-13 years). Harris scores, visual analogue scale (VAS) score, and the hip range of motion (ROM) were recorded at pre- and post-operation. The X-ray films were taken at pre- and post-operation to observe the position, loosening of the prosthesis, and ectopic ossification. The gait of patients were also evaluated during follow-up. Short-form 36 health survey scale (SF-36) was used to evaluate the life quality of patients. All 45 patients were followed up 5-8 years with an average of 6.4 years. All the incisions healed by first intention. No infection, hip dislocation, nerve injury, or deep vein thrombosis occurred. Six cleavage fractures (13.3%) of the lateral femoral diaphysis at the distal prosthesis occurred during operation, which healed at 8 months postoperatively without any treatment. Mild ectopic ossification occurred in 4 patients (8.9%) who had no discomfort. Five patients (11.1%) had bone mineral density loss in the region of the proximal femur. The survival rates of the cups and stems were all 100% at last follow-up. The results of Harris score, VAS score, and ROM of the hip joint at 1 year postoperatively and last follow-up were significantly better than preoperative ones (P 0.05) except the Harris score (P fair in 6 hips

  14. [EFFECTIVENESS OF ANATOMIC FEMORAL COMPONENT PROSTHESIS FOR SEVERE DEVELOPMENTAL DYSPLASIA OF THE HIP IN TOTAL HIP ARTHROPLASTY].

    Science.gov (United States)

    An, Xiao; Dong, Jiyuan; Gong, Ke; Zhang, Qi; Li, Xiang; Song, Wei

    2015-04-01

    To evaluate the effectiveness of anatomic femoral component prosthesis for severe development dysplasia of the hip (DDH) in total hip arthroplasty (THA). Between September 2009 and September 2013, 48 patients (51 hips) with severe DDH underwent THA with cementless anatomic femoral component prosthesis. There were 5 males (5 hips) and 43 females (46 hips) with an average age of 51 years (range, 28-67 years). The left hip was involved in 25 cases, the right hip in 20 cases, and bilateral hips in 3 cases. There were 39 cases (44 hips) of Crowe type III and 9 cases (7 hips) of Crowe type IV. The visual analogue scale (VAS) score was 5.72 +/- 1.84, and Harris score was 41.66 +/- 4.87 at preoperation. All patients had leg discrepancy with a length difference of (4.31 +/- 0.84) cm. The duration of surgery was 59-110 minutes (mean, 78.6 minutes), and the hospitalization days were 6-20 days (mean, 12.3 days). All patients obtained primary healing of incision without wound related complications of swelling, effusion, and infection. Two patients were found to have intramuscular venous thrombosis. All patients were followed up 10-54 months (mean, 29 months). Limp was observed at the early stage after operation in 9 patients and disappeared after 1 year, the other patients had normal gait. The VAS score 1.46?0.47, Harris score 88.66 +/- 3.48, and the leg length difference (1.15 +/- 0.33) cm at last follow-up all showed significant differences when compared with the preoperative values (Phip joint function and limb discrepancy. Short-term effectiveness was satisfactory, but the long-term effectiveness should still be observed in future.

  15. Ultrasound-Guided Femoral Nerve Block to Facilitate the Closed Reduction of a Dislocated Hip Prosthesis

    Directory of Open Access Journals (Sweden)

    Edward Carlin

    2017-10-01

    Full Text Available Prosthetic hip dislocation is a common but unfortunate complication in patients who have undergone total hip arthroplasty. Successful closed reduction in the emergency department leads to a reduced length of stay and rate of hospitalization. 1, 2 The use of regional anesthesia by femoral nerve block represents a novel approach for controlling pain in patients with hip pathologies. 3 Ultrasound-guided approaches have been used with great success for controlling pain in patients with hip fractures. 4, 5 Here we report the case of a 90-year-old male who presented with a dislocated hip prosthesis, which was subsequently corrected with closed reduction following delivery of regional anesthesia to the femoral nerve under ultrasound guidance. To our knowledge, this represents the first reported use of an ultrasound-guided femoral nerve block to facilitate closed reduction of a dislocated prosthetic hip, and highlights a novel approach that avoids the use of procedural sedation in an elderly patient.

  16. Monte Carlo calculations of the impact of a hip prosthesis on the dose distribution

    Science.gov (United States)

    Buffard, Edwige; Gschwind, Régine; Makovicka, Libor; David, Céline

    2006-09-01

    Because of the ageing of the population, an increasing number of patients with hip prostheses are undergoing pelvic irradiation. Treatment planning systems (TPS) currently available are not always able to accurately predict the dose distribution around such implants. In fact, only Monte Carlo simulation has the ability to precisely calculate the impact of a hip prosthesis during radiotherapeutic treatment. Monte Carlo phantoms were developed to evaluate the dose perturbations during pelvic irradiation. A first model, constructed with the DOSXYZnrc usercode, was elaborated to determine the dose increase at the tissue-metal interface as well as the impact of the material coating the prosthesis. Next, CT-based phantoms were prepared, using the usercode CTCreate, to estimate the influence of the geometry and the composition of such implants on the beam attenuation. Thanks to a program that we developed, the study was carried out with CT-based phantoms containing a hip prosthesis without metal artefacts. Therefore, anthropomorphic phantoms allowed better definition of both patient anatomy and the hip prosthesis in order to better reproduce the clinical conditions of pelvic irradiation. The Monte Carlo results revealed the impact of certain coatings such as PMMA on dose enhancement at the tissue-metal interface. Monte Carlo calculations in CT-based phantoms highlighted the marked influence of the implant's composition, its geometry as well as its position within the beam on dose distribution.

  17. Unusual cause of subluxation of Austin Moore prosthesis of the hip ...

    African Journals Online (AJOL)

    Subluxation and dislocation following hip arthroplasty is a well known complication. It can be due to a number of reasons - varying from malrotation of the component, operative approach, previous surgery, previous stroke, loosening and high wear rates of prosthesis, infection to even patient behaviour. In this study, an ...

  18. Total hip arthroplasty in young patients using the thrust plate prosthesis: clinical and radiological results.

    Science.gov (United States)

    Zelle, Boris A; Gerich, Torsten G; Bastian, Leonard; Shuler, Franklin D; Pape, Hans-Christoph; Krettek, Christian

    2004-06-01

    The standard treatment for patients who require total hip replacement is the implantation of an intramedullary diaphyseal anchored hip prosthesis. A bone-sparing thrust plate hip prosthesis (TPP) can be used as an alternative device for young patients. The TPP relies on proximal femoral metaphyseal fixation. The theoretical advantage of leaving diaphyseal bone intact is easier conversion to a stemmed prosthesis. This retrospective study evaluated the medium- and short-term results after total joint replacement using the third generation TPP. Between 1997 and 2001, 58 TPPs were used for 52 patients. Clinical and demographic data were obtained from the patients' charts and our electronic database. Their average age at time of surgery was 40.9+/-11.4 years. At follow-up, the Harris hip score, residual pain, required pain medication, and the ability to lie on the operated side were documented. Radiographic evaluation included standardized radiographs of the hip joint and the pelvis. Four patients required revision surgery (6.9%). For 51 of the remaining 54 TPPs, a postoperative functional and radiological status was obtained. The average follow-up was 26+/-11.0 months. 88% of the patients experienced some or complete relief of pain. The median Harris hip score at follow-up was 73+/-20.5 points. A postoperative hip dislocation occurred in 5 patients (8.6%). Since many patients experienced some or complete relief of pain, the TPP can be recommended as a feasible implant for the treatment of hip disorders requiring total hip arthroplasty in young patients. Revision surgeries are facilitated by the good bone stock remaining in the proximal femur.

  19. Monocular Vision- and IMU-Based System for Prosthesis Pose Estimation During Total Hip Replacement Surgery.

    Science.gov (United States)

    Su, Shaojie; Zhou, Yixin; Wang, Zhihua; Chen, Hong

    2017-06-01

    The average age of population increases worldwide, so does the number of total hip replacement surgeries. Total hip replacement, however, often involves a risk of dislocation and prosthetic impingement. To minimize the risk after surgery, we propose an instrumented hip prosthesis that estimates the relative pose between prostheses intraoperatively and ensures the placement of prostheses within a safe zone. We create a model of the hip prosthesis as a ball and socket joint, which has four degrees of freedom (DOFs), including 3-DOF rotation and 1-DOF translation. We mount a camera and an inertial measurement unit (IMU) inside the hollow ball, or "femoral head prosthesis," while printing customized patterns on the internal surface of the socket, or "acetabular cup." Since the sensors were rigidly fixed to the femoral head prosthesis, measuring its motions poses a sensor ego-motion estimation problem. By matching feature points in images of the reference patterns, we propose a monocular vision based method with a relative error of less than 7% in the 3-DOF rotation and 8% in the 1-DOF translation. Further, to reduce system power consumption, we apply the IMU with its data fused by an extended Kalman filter to replace the camera in the 3-DOF rotation estimation, which yields a less than 4.8% relative error and a 21.6% decrease in power consumption. Experimental results show that the best approach to prosthesis pose estimation is a combination of monocular vision-based translation estimation and IMU-based rotation estimation, and we have verified the feasibility and validity of this system in prosthesis pose estimation.

  20. SU-E-J-230: Effect of Metal Hip Prosthesis On the Accuracy of Electromagnetic Localization and Tracking

    Energy Technology Data Exchange (ETDEWEB)

    Butler, W; Merrick, G; Kurko, B [Wheeling Hospital, Wheeling, WV (United States); Bittner, N [Tacoma\\Valley Radiation Oncology, Tacoma, WA (United States)

    2014-06-01

    Purpose: To quantify the effect of metal hip prosthesis on the ability to track and localize electromagnetic transponders. Methods: Three Calypso transponders were implanted into two prostate phantoms. The geometric center of the transponders were identified on computed tomography and set as the isocenter. With the phantom stationary on the treatment table and the tracking array 14-cm above the isocenter, data was acquired by the Calypso system at 10 Hz to establish the uncertainty in measurements. Transponder positional data was acquired with unilateral hip prostheses of different metallic compositions and then with bilateral hips placed at variable separation from the phantom. Results: Regardless of hip prosthesis composition, the average vector displacement in the presence of a unilateral prosthesis was < 0.5 mm. The greatest contribution to overall vector displacement occurred in the lateral dimension. With bilateral hip prosthesis, the average vector displacement was 0.3 mm. The displacement in the lateral dimension was markedly reduced compared with a unilateral hip, suggesting that there was a countervailing effect with bilateral hip prosthesis. The greatest average vector displacement was 0.6 mm and occurred when bilateral hip prostheses were placed within 4 cm of the detector array. Conclusion: Unilateral and bilateral hip prostheses did not have any meaningful effect on the ability to accurately track electromagnetic transponders implanted in a prostate phantom. At clinically realistic distances between the hip and detection array, the average tracking error is negligible.

  1. SU-E-J-230: Effect of Metal Hip Prosthesis On the Accuracy of Electromagnetic Localization and Tracking

    International Nuclear Information System (INIS)

    Butler, W; Merrick, G; Kurko, B; Bittner, N

    2014-01-01

    Purpose: To quantify the effect of metal hip prosthesis on the ability to track and localize electromagnetic transponders. Methods: Three Calypso transponders were implanted into two prostate phantoms. The geometric center of the transponders were identified on computed tomography and set as the isocenter. With the phantom stationary on the treatment table and the tracking array 14-cm above the isocenter, data was acquired by the Calypso system at 10 Hz to establish the uncertainty in measurements. Transponder positional data was acquired with unilateral hip prostheses of different metallic compositions and then with bilateral hips placed at variable separation from the phantom. Results: Regardless of hip prosthesis composition, the average vector displacement in the presence of a unilateral prosthesis was < 0.5 mm. The greatest contribution to overall vector displacement occurred in the lateral dimension. With bilateral hip prosthesis, the average vector displacement was 0.3 mm. The displacement in the lateral dimension was markedly reduced compared with a unilateral hip, suggesting that there was a countervailing effect with bilateral hip prosthesis. The greatest average vector displacement was 0.6 mm and occurred when bilateral hip prostheses were placed within 4 cm of the detector array. Conclusion: Unilateral and bilateral hip prostheses did not have any meaningful effect on the ability to accurately track electromagnetic transponders implanted in a prostate phantom. At clinically realistic distances between the hip and detection array, the average tracking error is negligible

  2. Finite element study of contact pressure distribution on inner and outer liner in the bipolar hip prosthesis

    NARCIS (Netherlands)

    Saputra, E.; Anwar, I.B.; Ismail, R.; Jamari, J.; Heide, E. van der

    2016-01-01

    Wear in the hip prosthesis due to sliding contact as a product of human activity is a phenomenon which cannot be avoided. In general, there are two modelof hip prostheses which are widely used in total hip replacement, i.e. unipolar and bipolar models. Wear in the bipolar model is more complex than

  3. Finite element study of contact pressure distribution on inner and outer liner in the bipolar hip prosthesis

    NARCIS (Netherlands)

    Saputra, Eko; Anwar, Iwan Budiwan; Ismail, Rifky; Jamari, J.; van der Heide, Emile

    2016-01-01

    Wear in the hip prosthesis due to sliding contact as a product of human activity is a phenomenon which cannot be avoided. In general, there are two model of hip prostheses which are widely used in total hip replacement, i.e. unipolar and bipolar models. Wear in the bipolar model is more complex than

  4. bladder injury during infected total hip arthroplasty prosthesis

    African Journals Online (AJOL)

    Severe intrapelvic protrusions after total hip arthroplasty may occur in cases of chronic infection. During hip surgery, the components threating the neighboring organs were most often cement and screws than the cup itself. As expected, infection is another problem related to all implant surgeries. Bach et al (8) suggested that.

  5. Femoral artery occlusion secondary to a spontaneously "migrated" hip prosthesis: case report.

    Science.gov (United States)

    Tihan, Deniz Necdet; Aliş, Halil; Aksoy, Murat; Güloğlu, Recep; Kurtoğlu, Mehmet; Dikici, Fatih

    2010-03-01

    A 77-year-old male patient was admitted to the hospital with a worsening acute ischemia of the left lower extremity. The patient, who had a coxarthrosis and was being followed by the orthopedic clinic, had undergone a total hip prosthesis, with a revision performed at the sixth month of its placement. The physical examination revealed the absence of the femoral, popliteal and distal pulses of the left lower extremity. The left hip movements were painful and limited in external rotation posture. Doppler ultrasonography showed an acute occlusion of the left common femoral artery due to the dislocated hip prosthesis, and right-to-left femorofemoral expanded polytetrafluoroethylene graft bypass was carried out. After successful surgery and an uneventful postoperative period with palpable femoral and popliteal pulses, the patient was put on low molecular weight heparin and referred to orthopedics once the ischemia had subsided with the intervention. Case reports regarding occlusions due to migration of total hip prosthesis are rare in the literature. The emphasis of this case report is to describe one such case.

  6. No association between pseudotumors, high serum metal-ion levels and metal hypersensitivity in large-head metal-on-metal total hip arthroplasty at 5-7-year follow-up

    DEFF Research Database (Denmark)

    Hjorth, Mette Holm; Stilling, Maiken; Soballe, Kjeld

    2016-01-01

    (THA) and to investigate its relationship to serum metal-ion levels and hypersensitivity to metal. METHODS: Forty-one patients (31 males), mean age 52 (28-68) years, with a total of 49 large-head MoM THA participated in a 5-7-year follow-up study. Patients underwent ultrasonography, serum metal-ion...... concentrations were measured, metal allergy and atopic dermatitis were evaluated, and the questionnaires of the Oxford Hip Score (OHS), Harris Hip Score (HHS) and the Short-Form Health Survey (SF-36) were completed. RESULTS: Pseudotumors were found in eight patients, but they were asymptomatic and their serum...... metal-ion levels were similar to those observed in patients with no pseudotumors (p > 0.36). The capsule-stem distance of mean 8.6 mm (SD 3.82, 95% CI: 5.40-11.79) was wider (p = 0.02) in patients with pseudotumours than in patients without pseudotumors of mean 5.6 mm (SD 2.89, 95% CI: 4...

  7. Poor survival of ABG I hip prosthesis in younger patients

    Czech Academy of Sciences Publication Activity Database

    Gallo, J.; Langová, K.; Havránek, Vítězslav; Čechová, I.

    2008-01-01

    Roč. 152, č. 1 (2008), s. 152-163 ISSN 1213-8118 Institutional research plan: CEZ:AV0Z10100522 Keywords : total hip arthroplasty * ABG I * survival analysis * hydroxyapatie coating * osteolysis Subject RIV: BH - Optics, Masers, Lasers

  8. Metal release and metal allergy after total hip replacement with resurfacing versus conventional hybrid prosthesis

    Science.gov (United States)

    Gustafson, Klas; Jakobsen, Stig S; Lorenzen, Nina D; Thyssen, Jacob P; Johansen, Jeanne D; Bonefeld, Charlotte M; Stilling, Maiken; Baad-Hansen, Thomas; Søballe, Kjeld

    2014-01-01

    Background Metal-on-metal (MOM) total hip arthroplasties were reintroduced because of the problems with osteolysis and aseptic loosening related to polyethylene wear of early metal-on-polyethylene (MOP) arthroplasties. The volumetric wear rate has been greatly reduced with MOM arthroplasties; however, because of nano-size wear particles, the absolute number has been greatly increased. Thus, a source of metal ion exposure with the potential to sensitize patients is present. We hypothesized that higher amounts of wear particles result in increased release of metal ions and ultimately lead to an increased incidence of metal allergy. Methods 52 hips in 52 patients (median age 60 (51–64) years, 30 women) were randomized to either a MOM hip resurfacing system (ReCap) or a standard MOP total hip arthoplasty (Mallory Head/Exeter). Spot urine samples were collected preoperatively, postoperatively, after 3 months, and after 1, 2, and 5 years and tested with inductively coupled plasma-sector field mass spectrometry. After 5 years, hypersensitivity to metals was evaluated by patch testing and lymphocyte transformation assay. In addition, the patients answered a questionnaire about hypersensitivity. Results A statistically significant 10- to 20-fold increase in urinary levels of cobalt and chromium was observed throughout the entire follow-up in the MOM group. The prevalence of metal allergy was similar between groups. Interpretation While we observed significantly increased levels of metal ions in the urine during the entire follow-up period, no difference in prevalence of metal allergy was observed in the MOM group. However, the effect of long-term metal exposure remains uncertain. PMID:24930546

  9. A phantom study of dose compensation behind hip prosthesis using portal dosimetry and dynamic MLC

    International Nuclear Information System (INIS)

    Nielsen, Martin Skovmos; Carl, Jesper; Nielsen, Jane

    2008-01-01

    Background and purpose: A dose compensation method is presented for patients with hip prosthesis based on Dynamic Multi Leaves Collimator (DMLC) planning. Calculations are done from an exit Portal Dose Image (PDI) from 6 MV Photon beam using an Electronic Portal Imaging Device (EPID) from Varian. Four different hip prostheses are used for this work. Methods: From an exit PDI the fluence needed to yield a uniform dose distribution behind the prosthesis is calculated. To back-project the dose distribution through the phantom, the lateral scatter is removed by deconvolution with a point spread function (PSF) determined for depths from 10 to 40 cm. The dose maximum, D max , is determined from the primary plan which delivers the PDI. A further deconvolution to remove the dose glare effect in the EPID is performed as well. Additionally, this calculated fluence distribution is imported into the Treatment Planning System (TPS) for the final calculation of a DMLC plan. The fluence file contains information such as the relative central axis (CAX) position, grid size and fluence size needed for correct delivery of the DMLC plan. GafChromic EBT films positioned at 10 cm depth are used as verification of uniform dose distributions behind the prostheses. As the prosthesis is positioned at the phantom surface the dose verifications are done 10 cm from the prosthesis. Conclusion: The film measurement with 6 MV photon beam shows uniform doses within 5% for most points, but with hot/cold spots of 10% near the femoral head prostheses

  10. Effects of Prosthesis Stem Tapers on Stress Distribution of Cemented Hip Arthroplasty

    International Nuclear Information System (INIS)

    Abdullah, Abdul Halim; Nor, Mohd Asri Mohd; Saman, Alias Mohd; Tamin, Mohd Nasir; Kadir, Mohammed Rafiq Abdul

    2010-01-01

    Aseptic loosening effects are critical issues in encouraging long term stability of cemented hip arthroplasty. Stress shielding is believed to be an important factor that contributes to the aseptic loosening problems. The numerous changes in the prosthesis stem design are intended to minimize the stress shielding and aseptic loosening problems and to improve the long term performance of the implants. In this study, the stress distribution in cemented hip arthroplasty is established using finite element method. The taper of the prosthesis is designed to be 3 deg. at anterior/posterior, 3 deg. at medial/lateral and 10 deg. from wide lateral to narrow medial. Major muscle loads and contact forces are simulated for walking (toe-off phase) and stair climbing load cases. Effects of prosthesis stem tapers on the resulting stress distribution are investigated. Results show that compressive stress dominates in the medial plane while tensile stress in the lateral plane of the femur. The corresponding stress levels of intact femur for walking and stair-climbing load cases are 22 and 29 MPa, respectively. The magnitude of Tresca stress for the THA femur in stair-climbing load case remains higher in the region of 85 MPa while the walking load case induces around 40 MPa. The stress range in the straight and single taper stem prosthesis is lower than 260 MPa, while localized Tresca stress is in the order of the yield strength of Ti-6Al-4V alloy for double and triple taper stem design.

  11. Effects of Prosthesis Stem Tapers on Stress Distribution of Cemented Hip Arthroplasty

    Science.gov (United States)

    Abdullah, Abdul Halim; Nor, Mohd Asri Mohd; Saman, Alias Mohd; Tamin, Mohd Nasir; Kadir, Mohammed Rafiq Abdul

    2010-10-01

    Aseptic loosening effects are critical issues in encouraging long term stability of cemented hip arthroplasty. Stress shielding is believed to be an important factor that contributes to the aseptic loosening problems. The numerous changes in the prosthesis stem design are intended to minimize the stress shielding and aseptic loosening problems and to improve the long term performance of the implants. In this study, the stress distribution in cemented hip arthroplasty is established using finite element method. The taper of the prosthesis is designed to be 3° at anterior/posterior, 3° at medial/lateral and 10° from wide lateral to narrow medial. Major muscle loads and contact forces are simulated for walking (toe-off phase) and stair climbing load cases. Effects of prosthesis stem tapers on the resulting stress distribution are investigated. Results show that compressive stress dominates in the medial plane while tensile stress in the lateral plane of the femur. The corresponding stress levels of intact femur for walking and stair-climbing load cases are 22 and 29 MPa, respectively. The magnitude of Tresca stress for the THA femur in stair-climbing load case remains higher in the region of 85 MPa while the walking load case induces around 40 MPa. The stress range in the straight and single taper stem prosthesis is lower than 260 MPa, while localized Tresca stress is in the order of the yield strength of Ti-6Al-4V alloy for double and triple taper stem design.

  12. Metal allergy and second-generation metal-on-metal arthroplasties.

    Science.gov (United States)

    Cousen, Philippa J; Gawkrodger, David J

    2012-02-01

    There are concerns about the induction of metal allergy with second-generation metal-on-metal prostheses, and the role that this may play in the development of complications such as 'pseudotumours' or failure of the implant. In this review, we attempt to set out the current knowledge on this subject. From a review of the literature, it is apparent that the first-generation metal-on-metal replacement hips did cause metal sensitization, and that joint failure was associated with this, although it is still not clear which one led to the other. Highly engineered second-generation metal-on-metal arthroplasties used in joint resurfacings are now increasingly employed. Several studies have recently shown an association between metal sensitization and peri-implant hypersensitivity reactions and implant loosening and failure, although the overall risk appears to be low. The pragmatic approach adopted by most contact dermatologists for patients known to be allergic to nickel, cobalt or chromium and who require joint replacement is to recommend prostheses made of titanium-based alloys. Patch testing continues to be a useful tool as laboratory investigations for metal hypersensitivity continue to emerge. The development of guidelines on the management of patients receiving metal-on-metal arthroplasties suspected of being metal-allergic is desirable. © 2011 John Wiley & Sons A/S.

  13. Mechanical analysis of ceramic head for modular hip prosthesis

    International Nuclear Information System (INIS)

    Ravagli, E.

    1995-03-01

    A study, performed with the department of orthopaedics of the Rome Catholic University, has found out the two possible parameters mainly responsible for head breaking, i. e. errors in conical mating between head and stem, and cracks in the heads. This study has been continued in the frame of the STRIDE-CETMA project, aimed at founding and developing a centre for technologically advanced materials in Brindisi Technology Park (Italy). This report starts a systematic mechanical analysis of the above mentioned head, with the purpose of characterizing it exhaustively. The evaluations made lead to the conclusion that in nomimal conditions, the head is largely overdimensioned, taking into account the maximum load applied to the prosthesis

  14. [The standard implantation of a total hip prosthesis via two incisions (the Yale Technique)].

    Science.gov (United States)

    Kipping, Robert

    2009-09-01

    Implantation of a total hip endoprosthesis with minimal trauma to the soft tissue. The need for visual aids (e.g., navigation or X-rays) during the procedure is frequently avoided. All kinds of coxarthrosis for every age group, for every variation of bone construction, and even in obese patients. Extremely dysplastic hip joints involving the development of a secondary socket and the necessity of reconstruction of the acetabular socket (e.g., in the Harris method). Using a fixed lateral position, a small entry incision is made between the tensor fasciae latae and the sartorius muscles and the prosthesis socket is put into place. Via a second dorsal incision, after stripping the exterior rotators, the prosthesis stem and ball are implanted and the two parts of the prosthesis are attached. Full weight bearing allowed immediately. A luxation prophylaxis, in the form of a self-developed hip bodice (the so-called Yale bandage), is used until the end of the 4th postoperative week. Discharge from hospital is possible after just a few days. Upon discharge, the patient is sent to a rehabilitation facility, either as a resident or as an outpatient, for approximately 3 weeks. Return to the workplace, with only light physical activity, is possible once the wound has healed completely; this could be as soon as 14 days after the operation. Checkups are made after 4 weeks, 6 months, 1 year and then every year; these checkups include a full examination, X-rays and laboratory tests. Full exposure to sport or heavy manual labor is usually approved after the 6-month checkup. Between October 2004 and April 2006, a total of 221 patients underwent surgery using this new technique (of these 15 patients underwent two-stage bilateral hip joint replacements). Patients were followed up for a minimum of 12 months and a maximum of 30 months. The Harris Hip Score improved from an average of 45.25 preoperatively to 96.4 postoperatively.

  15. THE USE OF THE SADDLE PROSTHESIS FOR RECONSTRUCTION OF THE HIP-JOINT AFTER TUMOR RESECTION OF THE PELVIS

    NARCIS (Netherlands)

    VANDERLEI, B; HOEKSTRA, HJ; VETH, RPH; HAM, SJ; OLDHOFF, J; KOOPS, HS

    Reconstruction of the hip joint by a saddle prosthesis after excision of a malignant pelvic tumor is a relatively new method, which thus far has been mainly used for revision of infected hip arthroplasties. One patient with a metastatic cystosarcoma phyllodes and one patient with a chondrosarcoma of

  16. Tribological characterisation of UHMWPE used in dual mobility total hip prosthesis

    Science.gov (United States)

    Essefi, I.; Hakkouna, H.; Ouenzerfi, G.; Mollon, G.; Hamza, S.; Renault, E.; Berthier, Y.; Trunfio-Sfarghiu, A.-M.

    2016-08-01

    Total hip arthroplasty represents an effective solution for bone and joint diseases. Nevertheless, the hip prosthesis has a limited lifetime, in the average around fifteen years. Their improvement, especially their dual mobility is the objective of this study. Therefore, our strategy is focused on improving the material by comparing three types of polyethylene to determine the best one from a friction mechanism and wear rate minimization standpoint. A dual mobility hip prosthesis, containing a two-sided steel and cobalt chrome cup, was tested with a TORNIER hip joint simulator in calf serum. The rubbed surfaces were characterized using scanning electron microscopy (SEM), contact angle measurements, atomic force microscopy (AFM) and confocal fluorescence microscopy. All these multiscale characterization techniques (from nanoscale to millimeter and micro- scale) showed that the velocity accommodation mechanism is different from one type of polyethylene to another. The wear in the case of standard polyethylene was noticeable and the particles were large and scattered between the surface of polyethylene, the surface of the cup and in the calf serum. For the crosslinked polyethylene, the particles coming from the wear, were not as large, but they were spread the same way as the first case. Even though it shares the same accommodation principle on the detachment of the material with the crosslinked polyethylene the wear particles for the crosslinked vitaminized polyethylene were large and they were only found on the surface of the polyethylene.

  17. Metabolic Pattern of Asymptomatic Hip-Prosthesis by 18F-FDG-Positron-Emission-Tomography

    International Nuclear Information System (INIS)

    Beslic, Nermina; Heber, Daniel; Walter Lipp, Rainer; Sonneck-Koenne, Charlotte; Knoll, Peter; Mirzaei, Siroos

    2015-01-01

    Joint replacement is a procedure with a major impact on the quality of life of patients with joint degenerative disease or traumatic injuries. However, some patients develop symptoms after the intervention caused by mechanical loosening or infection. Metabolic imaging by 18F-FDG-PET investigated in these patients isoften hampered by low specificity for diagnosis of possible septic vs. mechanical loosening. The reason for this shortcoming is to our opinion the unawareness of physiological remodeling processes that could be seen in asymptomatic patients. In order to overcome this drawback, we aimed to find out the physiological metabolic functional pattern in asymptomatic patients with implanted hip prosthesis Twelve patients (6 males, 6 females); mean age 73 ± 7 (range 58 - 91) years were prospectively enrolled in the study. The patients were admitted to our department for oncological referral with implanted hip prostheses. All patients explained no symptoms with regard to their implanted prosthesis. The attenuation corrected images were used for analysis. Fourteen hip prostheses in 12 patients were visually analyzed. Seven out of 14 prostheses among 12 patients showed focal periprosthetic enhanced metabolism, two of which showed two sites of enhanced uptake; whereas, the remaining five prostheses showed singular hypermetabolic areas within the periprosthetic site. The remaining seven prostheses in the other five patients showed no periprosthetic-enhanced uptake. Of the asymptomatic patients investigated, 58% showed focal enhanced periprosthetic glucose metabolism. This finding should be taken into consideration as a more probable unspecific metabolic pattern for correct interpretation of 18F-FDG-PET studies in patients with suspected septic loosening of the hip prosthesis

  18. (99m)Tc-labeled ubiquicidin scintigraphy: a promising method in hip prosthesis infection diagnosis.

    Science.gov (United States)

    Aryana, K; Hootkani, A; Sadeghi, R; Davoudi, Y; Naderinasab, M; Erfani, M; Ayati, N

    2012-01-01

    Hip prosthesis implantation has witnessed a significant increase in recent years. Despite the advantages of this surgical procedure, it has some complications, the most serious of which is prosthetic infection. This study was conducted to investigate the feasibility of 99mTc-UBI scintigraphy in detection of infectious foci in painful hip prosthesis. UBI (Ubiquicidin 29-41) is an antimicrobial peptide fragment with the ability to target the bacterial colony directly. 34 patients, aged 20-79 years, with painful hip prosthesis were included. 99mTc-UBI scan and three phase bone scan were performed and two nuclear medicine specialists interpreted the UBI scans with and without bone scan results at hand. Both qualitative and semi-quantitative methods were used to interpret the 30 minute post injection images. The patients were actively followed up. According to the surgical findings, microbiological culture and active follow up, final diagnosis was made. 24 negative and 10 positive UBI scans were recorded. The sensitivity, specificity, negative and positive predictive values and accuracy of the study were all 100%. Bone scan did not have any influence on UBI interpretation. We were able to achieve excellent differentiation between infected and non-infected prostheses with a cut off value of 1.8 for target to non target (T/NT) ratio. No adverse effects were noticed following UBI scan. Based on the findings, the authors believe that 99mTc-UBI scintigraphy, with its high sensitivity and specificity, provides the physician with an excellent tool for differentiating infection from aseptic loosening of hip prostheses. Using this radiopharmaceutical, it is possible to obtain highly accurate results only 30 minutes after the beginning of the study.

  19. A Medical Wireless Measurement System for Hip Prosthesis Loosening Detection Based on Vibration Analysis

    Directory of Open Access Journals (Sweden)

    Sebastian Sauer

    2013-01-01

    Full Text Available Vibration analysis is a promising approach in order to detect early hip prosthesis loosening, with the potential to extend the range of diagnostic tools currently available in clinical routine. Ongoing research efforts and developments in the area of multi-functional implants, which integrate sensors, wireless power supply, communication and signal processing, provide means to obtain valuable in vivo information otherwise not available. In the current work a medical wireless measurement system is presented, which is integrated in the femoral head of a hip prosthesis. The passive miniaturized system includes a 3-axis acceleration sensor and signal pre-processing based on a lock-in amplifier circuit. Bidirectional data communication and power supply is reached through inductive coupling with an operating frequency of 125 kHz in accordance with the ISO 18000-2 protocol standard. The system allows the acquisition of the acceleration frequency response of the femur-prosthesis system between 500 to 2500 Hz. Applied laboratory measurements with system prototypes on artificial bones and integrated prostheses demonstrate the feasibility of the measurement system approach, clearly showing differences in the vibration behavior due to an implant loosening. In addition a possibility to evaluate the non-linear mechanic system behavior is presented.

  20. Infection or metal hypersensitivity? The diagnostic challenge of failure in metal-on-metal bearings.

    LENUS (Irish Health Repository)

    Galbraith, John G

    2011-04-01

    The use of second generation metal-on-metal hip articulations has gained favour in the past few years. A hypersensitivity reaction to the metal-on-metal bearing, although rare, is a reported complication and is a novel mode of failure of these implants. Differentiating failure secondary to infection from failure secondary to metal hypersensitivity represents a significant diagnostic challenge. A retrospective review of all cases of hip arthroplasty using metal-on-metal bearings over a 5-year period at a tertiary referral centre identified 3 cases of failure secondary to metal hypersensitivity. Clinical presentation, serological markers, radiological imaging and histological analysis of all cases identified were evaluated. Histological analysis of periprosthetic tissue in all 3 cases identified characteristic features such as perivascular lymphocytic aggregates and chronic inflammation consistent with aseptic lymphocytic vasculitis-associated lesions (ALVAL). This study highlights that failure secondary to metal hypersensitivity must be considered in patients presenting with the reappearance of persistent pain, marked joint effusion, and the development of early osteolysis in the absence of infection.

  1. Five-year results of a cementless short-hip-stem prosthesis

    Directory of Open Access Journals (Sweden)

    Ralf H. Wittenberg

    2013-03-01

    Full Text Available Hip prosthesis stems with a short stem length and proximal fixation geometry support a bone-preserving and muscle-sparing implantation and should also allow for revision surgery with a standard hip stem. We present 250 prospectively documented clinical and radiological results from the Metha Short Hip Stem prosthesis (B. Braun-Aesculap, Tuttlingen, Germany after an average follow-up of 4.9 years. The average patient age at surgery was 60 years. Indication for total hip replacement was primary osteoarthrosis (OA (78% of patients, OA based on developmental dyspla- sia of the hip (16%, and other indications (6%. At the last follow-up, the average Harris Hip Score was 97 points. 85% of patients were very satisfied and 14% were satisfied after surgery, whereas 1% were dissatisfied. Pain according to the Visual Analogue Scale improved from 7.4 (min 1.6, max 9.5 pre-operatively to 0.23 (min 0, max 6.6. No joint dislocations occurred when predominantly using 28 mm and 32 mm prosthesis heads. Nine short-stems were revised: three after bacterial infections, two after primary via valsa with penetration of the femoral cortex two and three months after surgery, and three after early aseptic cases of loosening within the first year. A further nine osseously consolidated short-stems had to be replaced due to breakage of the modular titanium cone adapter after an average of 3.1 years (min 1.9, max 4.4. All surgical revisions were performed using primary standard stems. Without taking the material-related adapter failures into account, a five year Kaplan-Meier survival rate of 96.7% (95% confidence interval 93.4-98.3 was determined for the short-stem prostheses. There were no radiological signs of loosening in any of the short-stem prostheses at the last examination. Fine sclerotic lines were detected in Gruen’s AP zones 1 (19% and 2 (10.5%, individual hypertrophies in zone 3 (3.5%, fine seams in zones 4 (5.5% and 5 (4%, without pedestal formations in zone 4

  2. Five-year results of a cementless short-hip-stem prosthesis.

    Science.gov (United States)

    Wittenberg, Ralf H; Steffen, Reinhard; Windhagen, Henning; Bücking, Petra; Wilcke, Andreas

    2013-02-22

    Hip prosthesis stems with a short stem length and proximal fixation geometry support a bone-preserving and muscle-sparing implantation and should also allow for revision surgery with a standard hip stem. We present 250 prospectively documented clinical and radiological results from the Metha Short Hip Stem prosthesis (B. Braun-Aesculap, Tuttlingen, Germany) after an average follow-up of 4.9 years. The average patient age at surgery was 60 years. Indication for total hip replacement was primary osteoarthrosis (OA) (78% of patients), OA based on developmental dysplasia of the hip (16%), and other indications (6%). At the last follow-up, the average Harris Hip Score was 97 points. 85% of patients were very satisfied and 14% were satisfied after surgery, whereas 1% were dissatisfied. Pain according to the Visual Analogue Scale improved from 7.4 (min 1.6, max 9.5) pre-operatively to 0.23 (min 0, max 6.6). No joint dislocations occurred when predominantly using 28 mm and 32 mm prosthesis heads. Nine short-stems were revised: three after bacterial infections, two after primary via valsa with penetration of the femoral cortex two and three months after surgery, and three after early aseptic cases of loosening within the first year. A further nine osseously consolidated short-stems had to be replaced due to breakage of the modular titanium cone adapter after an average of 3.1 years (min 1.9, max 4.4). All surgical revisions were performed using primary standard stems. Without taking the material-related adapter failures into account, a five year Kaplan-Meier survival rate of 96.7% (95% confidence interval 93.4-98.3) was determined for the short-stem prostheses. There were no radiological signs of loosening in any of the short-stem prostheses at the last examination. Fine sclerotic lines were detected in Gruen's AP zones 1 (19%) and 2 (10.5%), individual hypertrophies in zone 3 (3.5%), fine seams in zones 4 (5.5%) and 5 (4%), without pedestal formations in zone 4, clear

  3. A new hip epiphyseal prosthesis: design revision driven by a validated numerical procedure.

    Science.gov (United States)

    Martelli, S; Taddei, F; Cristofolini, L; Schileo, E; Rushton, N; Viceconti, M

    2011-12-01

    An innovative epiphyseal device has been recently proposed claiming an effective bone-prosthesis load transfer and a nearly physiological bone stresses distribution. However preliminary experimental tests showed a 23% weakening of the femoral neck after implantation. Aim of this study was to revise the prosthesis geometry with the goal of enhancing the femoral neck strength after implantation, while maintaining unchanged the initial conceptual design. To this aim, the risk of femoral neck fractures, prosthesis fractures, aseptic loosening and excessive bone resorption were addressed through a validated finite element procedure following a systematic approach. The initial prosthesis geometry was revised to reduce each investigated failure risk below the threshold of acceptance (100%). The new geometry was re-assessed to verify the effectiveness of the revision. The first design was predicted to locally induce high bone strains and cement stresses, which translated in a risk of bone and cement failure exceeding the threshold of acceptance (>100%). The revised design preserved a good stability of the device, contemporary reducing the risk for bone (45%) and cement (60%) failure. If results will be confirmed by statistical and clinical experimentations, current clinical indications for hip epiphyseal devices might be extended. Copyright © 2011 IPEM. All rights reserved.

  4. Debridement, antibiotics, irrigation, and retention (DAIR) of the prosthesis after hip hemiarthroplasty infections. Does it work?

    Science.gov (United States)

    Kazimoglu, Cemal; Yalcin, Nadir; Onvural, Burak; Akcay, Serkan; Agus, Haluk

    2015-08-01

    Debridement, antibiotic, and implant retention (DAIR) is an attractive treatment modality after hip hemiarthroplasty (HA) infections. Data about the success of the procedure after acute onset infections is lacking. The aim of this study was to analyze the clinical outcome and associated risk factors. A multicenter, retrospective cohort study was designed, including 39 patients with acute onset prosthetic infection who had undergone debridement and irrigation with prosthesis retention. The primary outcome measure was infection eradication without prosthesis removal. We also analyzed how the success rate was influenced by the length of the interval between implantation of the prosthesis and the beginning of the treatment. The overall success rate was 41%. Sedimentation rate over 60 mm/h and the longer duration (2 weeks) after prosthesis implantation were found as factors negatively influencing the success rate. Our results indicated limited success to DAIR- treated patients with infected HA. The high failure rate of DAIR treatment after 2 weeks from the implantation should be taken into consideration.

  5. Thermoelastic Femoral Stress Imaging for Experimental Evaluation of Hip Prosthesis Design

    Science.gov (United States)

    Hyodo, Koji; Inomoto, Masayoshi; Ma, Wenxiao; Miyakawa, Syunpei; Tateishi, Tetsuya

    An experimental system using the thermoelastic stress analysis method and a synthetic femur was utilized to perform reliable and convenient mechanical biocompatibility evaluation of hip prosthesis design. Unlike the conventional technique, the unique advantage of the thermoelastic stress analysis method is its ability to image whole-surface stress (Δ(σ1+σ2)) distribution in specimens. The mechanical properties of synthetic femurs agreed well with those of cadaveric femurs with little variability between specimens. We applied this experimental system for stress distribution visualization of the intact femur, and the femurs implanted with an artificial joint. The surface stress distribution of the femurs sensitively reflected the prosthesis design and the contact condition between the stem and the bone. By analyzing the relationship between the stress distribution and the clinical results of the artificial joint, this technique can be used in mechanical biocompatibility evaluation and pre-clinical performance prediction of new artificial joint design.

  6. Maintenance of bone mineral density after implantation of a femoral neck hip prosthesis.

    Science.gov (United States)

    Decking, Ralf; Rokahr, Christoph; Zurstegge, Matthias; Simon, Ulrich; Decking, Jens

    2008-01-31

    Stress shielding of the proximal femur has been observed in a number of conventional cementless implants used in total hip arthroplasty. Short femoral-neck implants are claiming less interference with the biomechanics of the proximal femur. The goal of this study was to investigate the changes of bone-mineral density in the proximal femur and the clinical outcome after implantation of a short femoral-neck prosthesis. We prospectively assessed the clinical outcome and the changes of bone mineral density of the proximal femur up to one year after implantation of a short femoral neck prosthesis in 20 patients with a mean age of 47 years (range 17 to 65). Clinical outcome was assessed using the Harris Hip Score. The WOMAC was used as a patient-relevant outcome-measure. The bone mineral density was determined using dual energy x-ray absorptiometry, performed 10 days, three months and 12 months after surgery. The Harris Hip Score improved from an average preoperative score of 46 to a postoperative score at 12 months of 89 points, the global WOMAC index from 5,3 preoperatively to 0,8 at 12 months postoperatively. In contrast to conventional implants, the DEXA-scans overall revealed a slight increase of bone mineral density in the proximal femur in the 12 months following the implantation. The short femoral neck stem lead to a distinct bone reaction. This was significantly different when compared to the changes in bone mineral density reported after implantation of conventional implants.

  7. [Impact of frailty factors in elderly people older than 75 years with prosthesis of the hip].

    Science.gov (United States)

    Dallière, O; Blanchon, M A; Blanc, P; Presles, E; Gonthier, R

    2004-11-01

    Hip pathology of hip requiring a surgical assumption of responsibility (coxarthrose invalidating, hip fracture) is increasing, and after the year 2025, the number of interventions will double. In parallel, the number of elderly people (older than 75 years) with malnutrition associated with cognitive impairment and reduced autonomy is on the increase. So the concept of frail elderly identified by specific criteria allows for better defining the health needs of heterogeneous elderly people. The objective of this study was to determine the influence of frailty factors on autonomy and clinical outcome after intervention for prosthesis of the hip. This prospective work, completed over 8 months, included 55 patients with total or intermediate prostheses of hip, whatever the cause, recruited from rehabilitation wards. Results from a pre-established questionnaire defined the personal status and social framework of these patients. A medical examination evaluated cognitive function Mini Mental State (MMS), nutritional state (IMC) and the level of autonomy immediately after surgery (the first 2 weeks) by the measurement of functional independence (MIF). The second MIF was carried out by the same operator at the end of the assumption of responsibility by the institution. Three factors of frailty influenced progress at the time of reacquisition of autonomy: cognitive impairment (P load and adaptation.

  8. EFFECTS OF DEXAMETHASONE AND PHENIRAMINE MALEATE ON HEMODYNAMIC AND RESPIRATORY PARAMETERS AFTER CEMENTATION IN CEMENTED PARTIAL HIP PROSTHESIS.

    Science.gov (United States)

    Yektaş, Abdulkadir; Gümüş, Funda; Totoz, Tolga; Gül, Nurten; Erkalp, Kerem; Alagöl, Ayşin

    2015-02-01

    To prevent hemodynamic and respiratory changes that are likely to occur during cementation in partial hip prosthesis by prophylactic use of pheniramine maleate and dexamethasone. The study included 40 patients aged between 60 and 85 years with an American Society ofAnesthesiologists (ASA) grade of II-III who underwent partial hip prosthesis. Just after spinal anesthesia, 4 mL normal saline was pushed in patients in Group S, whereas 45.5 mg pheniramine maleate and 8 mg dexamethasone mixture was pushed intravenously in a total volume of 4 mL in patients in Group PD. Amounts of atropine and adrenaline administered after cementation were significantly higher in Group S than in Group PD (P pheniramine maleate and dexamethasone in partial hip prosthesis led to an increase in SpO2 value and a decrease in the utilization of adrenaline and atropine after cementation.

  9. Resultados preliminares da artroplastia do quadril metal-metal de superfície: análise dos primeiros 40 casos com seguimento médio de 3 anos Preliminary outcomes of hip metal-on-metal resurfacing arthroplasty: an analysis of the first 40 cases with mean follow-up time of 3 years

    Directory of Open Access Journals (Sweden)

    Mauricio de Moraes

    2008-01-01

    Full Text Available Quarenta quadris (39 pacientes foram submetidos à artroplastia total metal-metal de superficie "resurfacing" entre 2002 e 2005. Todos foram estudados e analisados clinicamente e radiograficamente. Foram utilizados critérios clínicos, no pré e pós-operatório, pela avaliação de D'Aubigné e Postel. Radiograficamente, as áreas de radiolucência ao redor do acetábulo foram classificadas de acordo com DeLee e Charnley e, no fêmur nas zonas descritas por Amstutz et al. A idade média foi de 54,40 anos. O seguimento mínimo foi de 14 meses e o máximo de 51(média de 37,36 meses. 94,44% dos resultados clínicos foram satisfatórios no pós-operatório. Ocorreram 2 casos de soltura asséptica. Não houve fratura do fêmur durante o seguimento. Os autores consideraram esta opção técnica e de implante satisfatória e, com bons resultados no seguimento médio de 3 anos.Forty hips (39 patients were submitted to metal-on-metal hip replacement (resurfacing between 2002 and 2005. Evaluation was provided by clinical examination and X-ray tests. The authors performed clinical evaluations before and after surgery. The specific criterion applied was the D'Aubigné and Postel's classification. X-ray images showed radiolucent lines around the acetabular component on the zones described by DeLee and Charnley and around the femoral component on the zones described by Amstutz et al. The mean age was 54.40 years. The minimum follow-up period was 14 months (range:12 to 51 months. The outcomes of 94.44% of the patients in the study were postoperatively rated as satisfactory. There were 2 cases of aseptic loose and no neck-femoral fractures during the follow-up period. The authors concluded that this technique and implant alternative is satisfactory, with good early outcomes in a mean follow-up time of three years.

  10. The effect of a metal hip prosthesis on the radiation dose in therapeutic photon beam irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Lin, S.-Y.; Chu, T.-C. E-mail: tcchu@mx.nthu.edu.tw; Lin, J.-P.; Liu, M.-T

    2002-07-01

    Prostate and cervical cancer patients are often treated with external X-ray beams of bi-lateral incidence. Such treatment may incur some dose effect that cannot be predicted precisely in commercial treatment planning systems (TPS) for patients having undergone total hip replacement. This study performs a Monte Carlo (MC) simulation and an analytical calculation (convolution superposition algorithm which is implemented in ADAC TPS) of a 6 MV, 5x5 cm{sup 2} X-ray beam incident into water with the existence of hip prosthesis, e.g. Ti6Al4V and CoCrMo alloy. The results indicate that ADAC TPS cannot precisely account for the scatter and backscatter radiation that a metal hip prosthesis causes. For percent depth dose (PDD) curves, the maximum underdosage of ADAC TPS up to 5 mm above the interface between dense material and water is 5%, 20% and 27% for PDD{sub Bone}, PDD{sub Ti} and PDD{sub Co}, respectively. The dose re-buildup, which occurs behind the hip region, becomes more and more obvious for denser medium existed in water. Increasing inhomogeneity also enhances the underdosage of ADAC for greater depth (>10 cm), as the figures of nearly 2% in PDD{sub Bone}, PDD{sub Ti} and 4-5% in PDD{sub Co} reveal. Overestimating the attenuated power of high-density non-water material in ADAC TPS causes this underdosage. For dose profiles, no significant differences were found in Profile{sub Bone} at any depth. Profile{sub Ti} reveals that MC slightly exceeds ADAC at off-axis position 1.0-2.0 cm. Profile{sub Co} reveals this more obviously. This finding means that scatter radiation from these denser materials is significant and cannot be predicted precisely in ADAC.

  11. [50 years of total hip prosthesis--a tribute to Prof. Sir John Charnley].

    Science.gov (United States)

    Mikić, Zelimir Dj; Lesić, Aleksandar R

    2013-01-01

    November 2012 marked the 50th anniversary of the first implantation of a successful and long-lived hip endoprosthesis, which was performed by Prof Sir John Charnley in the "Centre for Hip Surgery" at a small country place in the north-west England. John Charnley (1911-1982) finished medical school at the Victoria University of Manchester in 1935, and than started training in orthopaedics at the Manchester Royal Infirmary, and completed it after the Second World War, in which he served as a volunteer. After that he continued working in the same hospital, and, apart from that he worked as a lecturer at the University of Manchester, and from 1949 as a visiting surgeon in the Wrightington Hospital. In 1958 Charnley decided to put his efforts into the development of hip replacement research and surgery, and initiated the foundation of the "Centre for Hip Surgery" with Biomechanical laboratory in the Wrightington Hospital in 1960, where the intesive basic and clinical research started, and becuase of that Charnley in 1962 left Manchester and moved with a full time practice at the Wrightington Hospital. That period of research time was not easy, there were many "trial and tribulations", but, owing to the tenacity and inventive mind of Charnley, in 1962 a new prosthesis consisting of a cemented metal stem with a 22 mm head articulating with a cemented polyethilene acetabular component, and with a low frictional torque was designed. The first such prosthesis, which later produced excellent long-term results, was implanted on November 22nd, 1962, and today, when we look back over a distance of fifty years, we can conclude that that day could be considered as a beginning of a modem aloarthroplastic surgery, and certainly as one of the greatest orthopaedic advance in the whole of the 20th century; and all that was initiated and promoted by Prof. Sir John Charnley.

  12. Biomechanical analysis and quantitative analysis of bone scintigraphy on thrust plate hip prosthesis.

    Science.gov (United States)

    Goto, Toshihiko; Yasunaga, Yuji; Takahashi, Kazuhiro; Ochi, Mitsuo

    2004-07-01

    To study the load distribution of the thrust plate hip prosthesis (TPP, Sulzer Medica, Baar, Switzerland) on femoral bone, a TPP insertion group and intramedullary cemented stem insertion group were prepared with the use of embalmed femoral anatomic specimens, and strain on the femoral bone induced by loading was measured. Bone scintigraphy was performed in 26 joints which underwent total hip arthroplasty with the use of TPP, to enable quantitative evaluation of postoperative remodeling of the bone. In the TPP insertion group, the strain was almost equivalent to that in the untreated femoral control group. On the other hand, compared with the control group and TPP insertion group, strain in the proximal portion of the femoral bone (medial side of the femoral neck) was significantly smaller in the cemented stem group (control group versus cemented stem insertion group, p=0.0062; cemented stem insertion group versus TPP 130 degrees insertion group, p=0.0005; cemented stem insertion group versus TPP 140 degrees insertion group, p=0.0031). Bone scintigrams revealed decreased uptake at 12 weeks after operation compared with 6 weeks after operation, indicating that TPP allows earlier implant stabilization than the conventional stem. Compared with the conventional stem, TPP is a prosthesis that can perform physiological load transmission.

  13. Hip prosthesis infection related to an unchecked intrauterine contraceptive device: a case report.

    Science.gov (United States)

    Ducharne, G; Girard, J; Pasquier, G; Migaud, H; Senneville, E

    2013-02-01

    Intrauterine devices (IUD) used for contraception can be the source of local infections or can migrate, which justifies regular checking recommendations and limitations around the implantation period. To our knowledge, bone and joint infections related to an infected IUD have not been described in the scientific literature. This paper reports on a case of the repeated infection of a total hip prosthesis related to an infected IUD that had been forgotten after being implanted 34years previously. The arthroplasty infection revealed itself through dislocation of a dual mobility cup. Commensal bacteria that colonize the female genital tract (Streptococcus agalactiae) were identified at the site of hip arthroplasty. This led to the discovery of the IUD that was infected by the same bacterium. Despite lavage of the non-loosened arthroplasty, removal of the IUD and 2months of antibiotic treatment, the dislocation recurred and the prosthesis was again infected with the same microorganism 4months later. This recurrence of the infection, with persistence of a uterine abscess containing the same bacterium, was treated with repeated lavage of the joint, total hysterectomy and antibiotics treatment. The infection had resolved when followed-up 3years later. The occurrence of a bone and joint infection with this type of bacterium should trigger the evaluation of a possible IUD infection. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  14. Bone-preserving prosthesis with a single axis for treating osteonecrosis of the femoral head: midterm results for the thrust plate hip prosthesis.

    Science.gov (United States)

    Yasunaga, Yuji; Goto, Toshihiko; Hisatome, Takashi; Tanaka, Ryuji; Yamasaki, Takuma; Ochi, Mitsuo

    2003-01-01

    We studied 27 patients (31 joints) who underwent total hip arthroplasty (THA) using the thrust plate hip prosthesis (TPP) for osteonecrosis of the femoral head. The mean follow-up period was 56 months (range 38-72 months). Clinical evaluation by the Merle d'Aubigne and Postel system showed a significant improvement from a preoperative mean score of 8.1 to a final mean follow-up score of 16.6. Mechanical loosening developed about 1 year postoperatively in one joint with a bone defect. Grade 1 stress shielding was observed in four joints. Although indications for the TPP are restricted to certain cases, unlike the conventional intramedullary stem, much can be expected of TPP. It is an outstanding prosthesis for osteonecrosis of the femoral head of young patients in terms of bone preservation and physiological load transfer.

  15. Numerical evaluation of bone remodelling and adaptation considering different hip prosthesis designs.

    Science.gov (United States)

    Levadnyi, Ievgen; Awrejcewicz, Jan; Gubaua, José Eduardo; Pereira, Jucélio Tomás

    2017-12-01

    The change in mechanical properties of femoral cortical bone tissue surrounding the stem of the hip endoprosthesis is one of the causes of implant instability. We present an analysis used to determine the best conditions for long-term functioning of the bone-implant system, which will lead to improvement of treatment results. In the present paper, a finite element method coupled with a bone remodelling model is used to evaluate how different three-dimensional prosthesis models influence distribution of the density of bone tissue. The remodelling process begins after the density field is obtained from a computed tomography scan. Then, an isotropic Stanford model is employed to solve the bone remodelling process and verify bone tissue adaptation in relation to different prosthesis models. The study results show that the long-stem models tend not to transmit loads to proximal regions of bone, which causes the stress-shielding effect. Short stems or application in the calcar region provide a favourable environment for transfer of loads to the proximal region, which allows for maintenance of bone density and, in some cases, for a positive variation, which causes absence of the aseptic loosening of an implant. In the case of hip resurfacing, bone mineral density changes slightly and is closest to an intact femur. Installation of an implant modifies density distribution and stress field in the bone. Thus, bone tissue is stimulated in a different way than before total hip replacement, which evidences Wolff's law, according to which bone tissue adapts itself to the loads imposed on it. The results suggest that potential stress shielding in the proximal femur and cortical hypertrophy in the distal femur may, in part, be reduced through the use of shorter stems, instead of long ones, provided stem fixation is adequate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Calculation of wear (f.i. wear modulus) in the plastic cup of a hip joint prosthesis

    NARCIS (Netherlands)

    Ligterink, D.J.

    1975-01-01

    The wear equation is applied to the wear process in a hip joint prosthesis and a wear modulus is defined. The sliding distance, wear modulus, wear volume, wear area, contact angle and the maximum normal stress were calculated and the theoretical calculations applied to test results. During the wear

  17. Successful Treatment of Candida Albicans-Infected Total Hip Prosthesis With Staged Procedure Using an Antifungal-Loaded Cement Spacer

    NARCIS (Netherlands)

    Deelstra, Jenneke J.; Neut, Danielle; Jutte, Paul C.

    We present a rare case of an immunocompetent host who developed a Candida albicans-infected total hip prosthesis. The infection could not be eradicated with debridement and extensive antifungal therapy. Our patient first underwent a resection of the proximal femur and local treatment with

  18. Design aspects and clinical performance of the thrust plate hip prosthesis.

    Science.gov (United States)

    Jacob, H A C; Bereiter, H H; Buergi, M L

    2007-01-01

    The thrust plate hip prosthesis (TPP) was conceived to maintain the physiological stress distribution in the proximal femur so as to prevent bone atrophy in this region, often encountered after implantation of conventional stem-type prostheses. A thrust plate of TiAlNb is firmly fixed to the neck of the femur by means of a forged CoCrMo bolt introduced through the lateral cortex, just below the greater trochanter, and through the metaphysis. A boss that contains the bolt head rests on the lateral cortex. A proximal extension from the thrust plate terminates in the ball head of the hip joint. Bone remodelling causes the initial prestressing of the structure (primary stability) to decline, but full integration of the thrust plate with the underlying host bone affords secondary stability. A total of 102 TPPs were implanted in the Cantonal Hospital, Chur, Switzerland, from 1992 to 1999 in 84 patients. The TPP was selected particularly for patients of the younger age group (26-76). Through its ability to load the medial cortex of the proximal femur in a physiological manner, the cortical bone in this region is preserved. The mean Harris hip score is 97 points and the survival rate 98 per cent, 144 months post-operatively.

  19. Prosthesis

    Science.gov (United States)

    A prosthesis is a device designed to replace a missing part of the body or to make a part of the body work better. Diseased or missing eyes, arms, hands, legs, or joints are commonly replaced by prosthetic devices. False teeth are known as dental prostheses. ...

  20. Carbon/PEEK composite materials as an alternative for stainless steel/titanium hip prosthesis: a finite element study.

    Science.gov (United States)

    Rezaei, Farshid; Hassani, Kamran; Solhjoei, Nosratollah; Karimi, Alireza

    2015-12-01

    Total hip replacement (THR) has been ranked within the most typical surgical processes in the world. The durability of the prosthesis and loosening of prosthesis are the main concerns that mostly reported after THR surgeries. In THR, the femoral prosthesis can be fixed by either cement or cementless methods in the patient's bones. In both procedures, the stability of the prosthesis in the hosted bone has a key asset in its long-term durability and performance. This study aimed to execute a comparative finite element simulation to assess the load transfer between the prosthesis, which is made of carbon/PEEK composite and stainless steel/titanium, and the femur bone. The mechanical behavior of the cortical bone was assumed as a linear transverse isotropic while the spongy bone was modeled like a linear isotropic material. The implants were made of stainless steel (316L) and titanium alloy as they are common materials for implants. The results showed that the carbon/PEEK composites provide a flatter load transfer from the upper body to the leg compared to the stainless steel/titanium prosthesis. Furthermore, the results showed that the von Mises stress, principal stress, and the strain in the carbon/PEEK composites prosthesis were significantly lower than that made of the stainless steel/titanium. The results also imply that the carbon/PEEK composites can be applied to introduce a new optimum design for femoral prosthesis with adjustable stiffness, which can decrease the stress shielding and interface stress. These findings will help clinicians and biomedical experts to increase their knowledge about the hip replacement.

  1. An investigation of the aseptic loosening of an AISI 316L stainless steel hip prosthesis.

    Science.gov (United States)

    Godec, Matjaz; Kocijan, Aleksandra; Dolinar, Drago; Mandrino, Djordje; Jenko, Monika; Antolic, Vane

    2010-08-01

    The total replacement of joints by the implantation of permanently indwelling prosthetic components has been one of the major successes of modern surgery in terms of relieving pain and correcting deformity. However, the aseptic loosening of a prosthetic-joint component is the most common reason for joint-revision surgery. Furthermore, it is thought that wear particles are one of the major contributors to the development and perpetuation of aseptic loosening. The aim of the present study was to identify the factors related to the aseptic loosening of an AISI 316L stainless steel total hip prosthesis. The stem was evaluated by x-ray photoelectron spectroscopy, with polished and rough regions being analyzed in order to establish the differences in the chemical compositions of both regions. Specific areas were examined using scanning electron microscopy with energy dispersive x-ray spectroscopy and light microscopy.

  2. Patients with metal-on-metal articulation in trapeziometacarpal total joint arthroplasty may have elevated serum chrome and cobalt.

    Science.gov (United States)

    Hansen, T B; Dremstrup, L; Stilling, M

    2013-10-01

    Serum chrome and cobalt was measured in 50 patients with trapeziometacarpal total joint replacement with metal-on-metal articulation and compared with serum chrome and cobalt values in 23 patients with trapeziometacarpal total joint replacement with metal-on-polyethylene articulation. In 10 of 50 (20%) patients with metal-on-metal articulation, slightly elevated serum chrome or cobalt values were found compared with only one in 23 (4%) patients with metal-on-polyethylene articulation. All metal values were lower than accepted 'normal values' for metal-on-metal hip arthroplasty and so considered not to be a general health risk. However, the mean disabilities of the arm, shoulder and hand (DASH) score was 24 in patients with elevated serum chrome or cobalt compared with 10 in patients with normal metal values (p chrome or cobalt values. We recommend that patients with trapeziometacarpal total joint replacement with metal-on-metal articulation are followed with DASH score and radiological examination every 3-5 years and serum chrome and cobalt should be analysed in symptomatic cases to learn more about possible local complications leading to, or arising from, metal debris.

  3. Determination of digitised radiograph magnification factors for pre-operative templating in hip prosthesis surgery

    Energy Technology Data Exchange (ETDEWEB)

    Descamps, Stephane [Hopital Gabriel Montpied, CHU de Clermont Ferrand, BP 69, Service de Chirurgie Orthopedique et Traumatologique, Clermont Ferrand Cedex 01 (France); Livesey, Christine; Learmonth, Ian Douglas [Southmead Hospital, Westbury-on-Trym, Bristol Implant Research Centre, Avon Orthopaedic Centre, Bristol (United Kingdom)

    2010-03-15

    With digital radiography development, information technology (IT) companies have developed specific software for templating procedures, requiring individual magnification assessments for each patient. The aim of this study was to determine the mean magnification factor of digital radiographs and to evaluate the possibility of using the mean magnification factor or clinical information in templating. We retrospectively evaluated 100 primary total hip arthroplasty digital radiographs using the femoral head prosthesis as a calliper to determinate the mean magnification factor. Working on the assumption that altitude of the hip during radiograph is decisive in modification of magnification factors, we also looked for a correlation between weight, body mass index (BMI), altitude and magnification factor. The magnification factor was 126% (121-130%). A relationship was found between magnification factor (Mf) and weight (Mf = 7.10{sup -4} x weight (kg) + 1.21), but not BMI. In 98% of cases, if the weight-correlated formula is used, the sizing is correct or the error is {+-} 1 mm. With the mean method the sizing is correct or within 1 mm in only 78.2% of cases. Levels of accuracy for the mean magnification factor and the weight-correlated formula are not as high as individual assessments using a calliper; however, they could be used in everyday practice where individual magnification factors have not been calculated. (orig.)

  4. Painful prosthesis: approaching the patient with persistent pain following total hip and knee arthroplasty

    Science.gov (United States)

    Piscitelli, Prisco; Iolascon, Giovanni; Innocenti, Massimo; Civinini, Roberto; Rubinacci, Alessandro; Muratore, Maurizio; D’Arienzo, Michele; Leali, Paolo Tranquilli; Carossino, Anna Maria; Brandi, Maria Luisa

    2013-01-01

    Summary Background Symptomatic severe osteoarthritis and hip osteoporotic fractures are the main conditions requiring total hip arthroplasty (THA), whereas total knee arthroplasty (TKA) is mainly performed for pain, disability or deformity due to osteoarthritis. After surgery, some patients suffer from “painful prosthesis”, which currently represents a clinical problem. Methods A systematic review of scientific literature has been performed. A panel of experts has examined the issue of persistent pain following total hip or knee arthroplasty, in order to characterize etiopathological mechanisms and define how to cope with this condition. Results Four major categories (non infective, septic, other and idiopathic causes) have been identified as possible origin of persistent pain after total joint arthroplasty (TJA). Time to surgery, pain level and function impairment before surgical intervention, mechanical stress following prosthesis implant, osseointegration deficiency, and post-traumatic or allergic inflammatory response are all factors playing an important role in causing persistent pain after joint arthroplasty. Diagnosis of persistent pain should be made in case of post-operative pain (self-reported as VAS ≥3) persisting for at least 4 months after surgery, or new onset of pain (VAS ≥3) after the first 4 months, lasting ≥2 months. Acute pain reported as VAS score ≥7 in patients who underwent TJA should be always immediately investigated. Conclusions The cause of pain needs always to be indentified and removed whenever possible. Implant revision is indicated only when septic or aseptic loosening is diagnosed. Current evidence has shown that peri-and/or post-operative administration of bisphosphonates may have a role in pain management and periprosthetic bone loss prevention. PMID:24133526

  5. [15-year results following implantation of a stem type AML hip prosthesis].

    Science.gov (United States)

    Schwerter, K; Meyenberg, A; Sander, K; Layher, F; Roth, A

    2013-06-01

    The trend in arthroplasty of the hip joint to implement new models is partly based on theoretical considerations. In order to verify to which extent the philosophy of individual models is ultimately successful, the presentation of long-term results is required. In the years 1991 and 1992, 433 patients with primary implantation of an uncemented total hip replacement in primary coxarthrosis with a stem type AML (anatomic medullary locking) were treated surgically. 283 of them got a cementless cup type Duraloc. In 311 (71.8 %) patients the mean survival rate of the prosthesis could be determined at a mean follow-up of 15.5 years. 145 (33.5 %) patients were followed up completely both clinically and radiologically. Radiographically, the stem position, changes of the periprosthetic bone of the stem and the cup, as well as the wear of the cups were examined. The cumulative survival rate of the AML stem after 15.5 years was 97.5 %, of the Duraloc cup 88.2 %. The clinical results of the hip scores according to Harris and Merle d'Aubigné were good and excellent and patient satisfaction was very high. There was no relationship between stem position, stress shielding and surrounding lyses at the femur and the acetabulum and survival of stem or cup. There was no correlation between inlay wear and survival of the Duraloc cup. A subsiding of the stem in 2 cases had no effect on the clinical symptoms and quality of life. The press-fit implanted AML stem and the Duraloc cup revealed very good results during the investigation period. Like other implants, the survival rate is limited at the presented implant mainly by the cup. Georg Thieme Verlag KG Stuttgart · New York.

  6. Assessment of femoral neck fracture risk for a novel proximal epiphyseal hip prosthesis.

    Science.gov (United States)

    Cristofolini, Luca; Juszczyk, Mateusz; Taddei, Fulvia; Field, Richard E; Rushton, Neil; Viceconti, Marco

    2011-07-01

    This study addresses the risk of femoral neck fracture associated with resurfacing hip prostheses. A novel cemented Proximal Epiphyseal Replacement (PER) featuring a short curved stem was investigated. Seven pairs of femurs were in vitro tested. One femur of each pair was randomly assigned for PER implantation. The contralateral femur was tested intact. All femurs were loaded to failure in a validated, physiological configuration. High-speed videos (10,000-12,000 frames/s) were acquired to identify the location of fracture initiation. For comparison, data were included from Birmingham Hip Resurfacing previously tested in an identical fashion (N=3). Relative to the contralateral intact femurs, the failure load of the PER and Birmingham implants was 15.4% higher and 10.0% lower, respectively. In six of the seven PER implants, fracture initiation (neck or inter-trochanteric) was similar to the contralateral intact femurs, suggesting comparable stress distribution. Conversely, fracture initiation in the Birmingham implants occurred at the lateral prosthesis rim, which differed substantially from the intact femurs. No correlation existed between bone quality and strengthening/weakening effect of the PER (failure load of implant as a percentage of intact: R^2=0.067). Conversely, Birmingham implantation weakened the femurs with lower density (R^2=0.92). Therefore, unlike most resurfacing prostheses, the PER seems suitable also for osteoporotic subjects. This study seems to confirm that resurfacing with a Birmingham Hip tends to reduce the strength of the proximal femur. The opposite seemed to happen with the PER, which slightly reduced the risk of neck fracture, also in low-quality bones. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Development and first validation of a simplified CT-based classification system of soft tissue changes in large-head metal-on-metal total hip replacement: intra- and interrater reliability and association with revision rates in a uniform cohort of 664 arthroplasties

    International Nuclear Information System (INIS)

    Boomsma, Martijn F.; Warringa, Niek; Edens, Mireille A.; Lingen, Christiaan P. van; Ettema, Harmen B.; Verheyen, Cees C.P.M.; Maas, Mario

    2015-01-01

    After implantation of a metal-on-metal total hip arthroplasty (MoM THA), a large incidence of pseudotumor formation has been described recently. Several centers have invited patients for follow-up in order to screen for pseudotumor formation. The spectrum of abnormalities found by CT in MoM THA patients can be unfamiliar to radiologists and orthopedic surgeons. Previously, a CT five-point grading scale has been published. In this paper, a simplification into a three-point classification system gives insight in the morphological distinction of abnormalities of the postoperative hip capsule in MoM implants in relation to the decision for revision. The reliability of this simplified classification regarding intra- and interrater reliability and its association with revision rate is investigated and discussed. All patients who underwent MoM THA in our hospital were invited for screening. Various clinical measures and CT scan were obtained in a cross-sectional fashion. A decision on revision surgery was made shortly after screening. CT scans were read in 582 patients, of which 82 patients were treated bilaterally. CT scans were independently single read by two board-certified radiologists and classified into categories I-V. In a second meeting, consensus was obtained. Categories were subsequently rubricated in class A (categories I and II), B (category III), and C (categories IV and V). Intra- and inter-radiologist agreement on MoM pathology was assessed by means of the weighted Cohen's kappa. Categorical data were presented as n (%), and tested by means of Fisher's exact test. Continuous data were presented as median (min-max) and tested by means of Mann-Whitney U test (two group comparison) or Kruskal-Wallis test (three group comparison). Logistic regression analysis was performed in order to study independence of CT class for association with revision surgery. Univariate statistically significant variables were entered in a multiple model. All statistical

  8. Development and first validation of a simplified CT-based classification system of soft tissue changes in large-head metal-on-metal total hip replacement: intra- and interrater reliability and association with revision rates in a uniform cohort of 664 arthroplasties

    Energy Technology Data Exchange (ETDEWEB)

    Boomsma, Martijn F.; Warringa, Niek [Isala Hospital, Department of Radiology, Zwolle (Netherlands); Edens, Mireille A. [Isala Hospital, Department of Innovation and Science, Zwolle (Netherlands); Lingen, Christiaan P. van; Ettema, Harmen B.; Verheyen, Cees C.P.M. [Isala Hospital, Department of Orthopaedics, Zwolle (Netherlands); Maas, Mario [AMC, Department of Radiology, Amsterdam (Netherlands)

    2015-08-15

    After implantation of a metal-on-metal total hip arthroplasty (MoM THA), a large incidence of pseudotumor formation has been described recently. Several centers have invited patients for follow-up in order to screen for pseudotumor formation. The spectrum of abnormalities found by CT in MoM THA patients can be unfamiliar to radiologists and orthopedic surgeons. Previously, a CT five-point grading scale has been published. In this paper, a simplification into a three-point classification system gives insight in the morphological distinction of abnormalities of the postoperative hip capsule in MoM implants in relation to the decision for revision. The reliability of this simplified classification regarding intra- and interrater reliability and its association with revision rate is investigated and discussed. All patients who underwent MoM THA in our hospital were invited for screening. Various clinical measures and CT scan were obtained in a cross-sectional fashion. A decision on revision surgery was made shortly after screening. CT scans were read in 582 patients, of which 82 patients were treated bilaterally. CT scans were independently single read by two board-certified radiologists and classified into categories I-V. In a second meeting, consensus was obtained. Categories were subsequently rubricated in class A (categories I and II), B (category III), and C (categories IV and V). Intra- and inter-radiologist agreement on MoM pathology was assessed by means of the weighted Cohen's kappa. Categorical data were presented as n (%), and tested by means of Fisher's exact test. Continuous data were presented as median (min-max) and tested by means of Mann-Whitney U test (two group comparison) or Kruskal-Wallis test (three group comparison). Logistic regression analysis was performed in order to study independence of CT class for association with revision surgery. Univariate statistically significant variables were entered in a multiple model. All statistical

  9. A case study of radiotherapy planning for a bilateral metal hip prosthesis prostate cancer patient

    International Nuclear Information System (INIS)

    Su, Andy; Reft, Chester; Rash, Carla; Price, Jennifer; Jani, Ashesh B.

    2005-01-01

    The purpose of this report is to communicate the observed advantage of intensity-modulated radiotherapy (IMRT) in a patient with bilateral metallic hip prostheses. In this patient with early-stage low-risk disease, a dose of 74 Gy was planned in two phases-an initial 50 Gy to the prostate and seminal vesicles and an additional 24 Gy to the prostate alone. Each coplanar beam avoided the prosthesis in the beam's eye view. Using the same target expansions for each phase, IMRT and 3D-conformal radiotherapy (CRT) plans were compared for target coverage and inhomogeneity as well as dose to the bladder and rectum. The results of the analysis demonstrated that IMRT provided superior target coverage with reduced dose to normal tissues for both individual phases of the treatment plan as well as for the composite treatment plan. The dose to the rectum was significantly reduced with the IMRT technique, with a composite V80 of 35% for the IMRT plan versus 70% for 3D-CRT plan. Similarly, the dose to the bladder was significantly reduced with a V80 of 9% versus 20%. Overall, various dosimetric parameters revealed the corresponding 3D-CRT plan would not have been acceptable. The results indicate significant success with IMRT in a clinical scenario where there were no curative alternatives for local treatment other than external beam radiotherapy. Therefore, definitive external beam radiation of prostate cancer patients with bilateral prosthesis is made feasible with IMRT. The work described herein may also have applicability to other groups of patients, such as those with gynecological or other pelvic malignancies

  10. Shielding of the Hip Prosthesis During Radiation Therapy for Heterotopic Ossification is Associated with Increased Failure of Prophylaxis

    International Nuclear Information System (INIS)

    Balboni, Tracy A.; Gaccione, Peter; Gobezie, Reuben; Mamon, Harvey J.

    2007-01-01

    Purpose: Radiation therapy (RT) is frequently administered to prevent heterotopic ossification (HO) after total hip arthroplasty (THA). The purpose of this study was to determine if there is an increased risk of HO after RT prophylaxis with shielding of the THA components. Methods and Materials: This is a retrospective analysis of THA patients undergoing RT prophylaxis of HO at Brigham and Women's Hospital between June 1994 and February 2004. Univariate and multivariate logistic regressions were used to assess the relationships of all variables to failure of RT prophylaxis. Results: A total of 137 patients were identified and 84 were eligible for analysis (61%). The median RT dose was 750 cGy in one fraction, and the median follow-up was 24 months. Eight of 40 unshielded patients (20%) developed any progression of HO compared with 21 of 44 shielded patients (48%) (p = 0.009). Brooker Grade III-IV HO developed in 5% of unshielded and 18% of shielded patients (p 0.08). Multivariate analysis revealed shielding (p = 0.02) and THA for prosthesis infection (p = 0.03) to be significant predictors of RT failure, with a trend toward an increasing risk of HO progression with age (p = 0.07). There was no significant difference in the prosthesis failure rates between shielded and unshielded patients. Conclusions: A significantly increased risk of failure of RT prophylaxis for HO was noted in those receiving shielding of the hip prosthesis. Shielding did not appear to reduce the risk of prosthesis failure

  11. Incidence and management of hip dislocation in tumour patients with a modular prosthesis of the proximal femur.

    Science.gov (United States)

    Puchner, Stephan E; Funovics, Philipp T; Hipfl, Christian; Dominkus, Martin; Windhager, Reinhard; Hofstaetter, Jochen G

    2014-08-01

    Little data is available about the incidence and especially the management of hip dislocation following the implantation of modular tumor prostheses of the proximal femur. In this retrospective single-centre study we assessed the incidence of hip dislocation following implantation of a proximal femoral modular prosthesis as well as the success of the subsequent surgical or non-surgical treatment in tumor patients. Between 1982 and 2008, 166 tumor patients received a modular prosthesis of the proximal femur at our institution. The average age at the time of surgery was 50 ± 20 years (range, six to 84 years). An additional pelvic reconstruction was done in 14 patients. An artificial band for soft tissue reconstruction of the hip was used in 19 patients. The average time of follow-up was 46 ± 64 months (range, one to 277 months). The overall dislocation rate after proximal femoral replacement was 13% after a mean time of seven ± eight months (range, 0.3-33 months) after surgery. Between 1982 and 1986 the dislocation rate was 33% and declined to 9% in subsequent years (1987-2008). Patients who had received an additional pelvic reconstruction had a three fold higher dislocation rate (p prosthesis of the proximal femur is a common complication, especially in cases with additional pelvic resection with extensive bone and soft-tissue defects. Open surgical management may be more effective in preventing re-dislocation than closed reduction and bracing alone.

  12. Evaluation of ranges of motion of a new constrained acetabular prosthesis for canine total hip replacement

    Science.gov (United States)

    2013-01-01

    Background Total hip replacement (THR) is considered to be the most effective treatment option for advanced osteoarthritis of the hip in large breed dogs. However, a proportion of post-THR patients suffer prosthesis dislocation for various reasons, which may be addressed by a constrained acetabular prosthesis design. The study proposed a new THR with constrained acetabular component that aimed to decrease the incidence of postoperative dislocation while maintaining the necessary range of motion (ROM); and, through computer-simulated implantations, evaluated the ROM of the THR with and without malpositioning of the acetabular component. Methods A new THR with a constrained acetabular component that had an inward eccentric lining and a 60° cut-out on the dorsal side was designed, and its computer-aided design models were implanted into the pelvic and femoral models reconstructed from the computed tomography data of six healthy Labrador Retriever dogs. The allowable and functional ROM of the implanted THR were determined via computer simulations. The contact patterns between the bone or the prosthetic components at extreme positions of the THR were analyzed. Influence of malpositioning of the acetabular component on the ROM was assessed. Results The means (SD) of the functional ranges for flexion, extension, adduction, abduction, internal rotation and external rotation were 51.8° (6.6°), 163.3° (7.3°), 33.5° (5.7°), 74.0° (3.7°), 41.5° (8.3°) and 65.2° (9.9°), respectively. Malpositioning of the acetabular component by 20° in one direction was found to reduce ROM in other directions (reducing lateral opening: flexion: 12°, adduction: 20°, internal/external rotations: < 20°; increasing lateral opening: extension and abduction: < 16°; reducing retroversion: extension: < 20°, abduction: 15°, external rotation: < 20°; increasing retroversion: flexion: < 20°, abduction, adduction and internal rotation: 20°). Conclusions From the computer

  13. Wear mechanisms in ceramic hip implants.

    Science.gov (United States)

    Slonaker, Matthew; Goswami, Tarun

    2004-01-01

    The wear in hip implants is one of the main causes for premature hip replacements. The wear affects the potential life of the prosthesis and subsequent removals of in vivo implants. Therefore, the objective of this article is to review various joints that show lower wear rates and consequently higher life. Ceramics are used in hip implants and have been found to produce lower wear rates. This article discusses the advantages and disadvantages of ceramics compared to other implant materials. Different types of ceramics that are being used are reviewed in terms of the wear characteristics, debris released, and their size together with other biological factors. In general, the wear rates in ceramics were lower than that of metal-on-metal and metal-on-polyethylene combinations.

  14. Finite element study of contact pressure distribution on inner and outer liner in the bipolar hip prosthesis

    Science.gov (United States)

    Saputra, Eko; Anwar, Iwan Budiwan; Ismail, Rifky; Jamari, J.; van der Heide, Emile

    2016-04-01

    Wear in the hip prosthesis due to sliding contact as a product of human activity is a phenomenon which cannot be avoided. In general, there are two modelof hip prostheses which are widely used in total hip replacement, i.e. unipolar and bipolar models. Wear in the bipolar model is more complex than the unipolar model due to its contact motion. The bipolar model has two contact mechanisms while the unipolar model has only one contact mechanism. It means that the bipolar model has two wear positions, i.e. wear on inner and outer liner surface. Fortunately, wear phenomena in the hip prosthesis can be predicted by analytical or numerical method. Wear on the inner and outer liner surface in the bipolar model itself can be early predicted by contact pressure distribution that is obtained from contact mechanic analysis.The contact pressure distribution itself is an essential variable in wear equations. This paper is aimed to studythe difference of the contact pressure distribution on the inner and outer liner surface in the bipolar model. To obtain the contact pressure distribution at each surface, contact mechanic analysis on the inner and outer liner surface by analytical and numerical method were performed. Results showedthat there was significant difference of the contact pressure distribution on the inner and outer liner surface in the bipolar model. Therefore, it is expected that there is significant wear difference on the inner and outer liner in the bipolar model.

  15. The Thrust Plate Hip Prosthesis: A Follow-Up of 15-20 Years With 102 Implants.

    Science.gov (United States)

    Kaegi, Maja; Buergi, Martin L; Jacob, Hilaire A C; Bereiter, Heinz H

    2016-05-01

    Between November 1992 and January 1999, a cohort of 102 thrust plate hip prostheses was implanted. We now clinically and radiologically evaluate the remaining 73 prostheses with a mean follow-up of 17.2 years. The Harris Hip Score increased from 51.4 points preoperatively to 94.3 points at the time of this follow-up. No further changes in the radiologic findings occurred since the first follow-up, published in 2005, conducted 2-8 years after implantation. Within 15 to 20 years after primary implantation of the 102 prostheses, 6 aseptic loosenings occurred, which correspond to a cumulated survival rate of 94.7% at 17 and 91.8% at 18 years. Although the thrust plate hip prostheses is no longer marketed, the biomechanical behaviour of this unique, clinically successful prosthesis deserves attention. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Use of a long distally fixed intramedullary stem to treat a periprosthetic femoral fracture following total hip arthroplasty using a thrust plate hip prosthesis: A case report.

    Science.gov (United States)

    Hatanaka, Hiroyuki; Motomura, Goro; Ikemura, Satoshi; Sonoda, Kazuhiko; Kubo, Yusuke; Utsunomiya, Takeshi; Yamamoto, Takuaki; Nakashima, Yasuharu

    2017-01-01

    The thrust plate hip prosthesis (TPP; Zimmer, Winterthur, Switzerland) is a hip prosthesis that is no longer in production. Few reports have focused on periprosthetic fractures following total hip arthroplasty (THA) with the use of a TPP. We report a 57-year-old woman with a periprosthetic femoral fracture 13 years after THA with the use of a TPP. A plain radiograph showed a displaced subtrochanteric fracture of the right femur just below the distal tip of the lateral plate without implant loosening. She underwent revision surgery with a long distally fixed intramedullary stem in conjunction with a plate and cable system. Three months after surgery, bone union was confirmed using radiography and the patient was clinically asymptomatic. We encountered three major problems while planning surgical treatment, these being, discontinuation of the TPP system, loss of proximal femoral cancellous bone, and difficulties with the type of subtrochanteric fracture. After considering these problems, we planned revision surgery using a long distally fixed intramedullary stem in conjunction with a plate and cable system. This case shows that sufficient implant preparation based on precise preoperative planning is necessary to obtain good clinical results for the surgical treatment of periprosthetic femoral fractures following THA with the use of a TPP. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  17. Comparison and Combination of Dual-Energy- and Iterative-Based Metal Artefact Reduction on Hip Prosthesis and Dental Implants.

    Science.gov (United States)

    Bongers, Malte N; Schabel, Christoph; Thomas, Christoph; Raupach, Rainer; Notohamiprodjo, Mike; Nikolaou, Konstantin; Bamberg, Fabian

    2015-01-01

    To compare and combine dual-energy based and iterative metal artefact reduction on hip prosthesis and dental implants in CT. A total of 46 patients (women:50%,mean age:63±15years) with dental implants or hip prostheses (n = 30/20) were included and examined with a second-generation Dual Source Scanner. 120kV equivalent mixed-images were derived from reconstructions of the 100/Sn140kV source images using no metal artefact reduction (NOMAR) and iterative metal artefact reduction (IMAR). We then generated monoenergetic extrapolations at 130keV from source images without IMAR (DEMAR) or from source images with IMAR, (IMAR+DEMAR). The degree of metal artefact was quantified for NOMAR, IMAR, DEMAR and IMAR+DEMAR using a Fourier-based method and subjectively rated on a five point Likert scale by two independent readers. In subjects with hip prosthesis, DEMAR and IMAR resulted in significantly reduced artefacts compared to standard reconstructions (33% vs. 56%; for DEMAR and IMAR; respectively, pdental implants only IMAR showed a significant reduction of artefacts whereas DEMAR did not (71%, vs. 8% pprosthesis: 47%, dental implants 18%; both pdental implants, compared to a dual energy based method. The combination of DE-source images with IMAR and subsequent monoenergetic extrapolation provides an incremental benefit compared to both single methods.

  18. A Stereophotogrammetric System For The Detection Of Prosthesis Loosening In Total Hip Arthroplasty

    Science.gov (United States)

    Baumrind, Sheldon; Genant, Harry K.; Hunter, John; Miller, David; Moffitt, Francis; Murray, William R.; Ross, Steven E.

    1980-07-01

    Loosening of the prosthetic device occurs in about 5% of cases following placement of total hip prostheses (THP). Early detection of loosening is much desired but is difficult to achieve using conventional methods. Due to errors of projection, it is quite possible to fail to detect mobility of even as much as 5 mm on single x-ray films. We are attempting to develop a simplified photogrammetric system suitable for general hospital use which could detect loosening of 0.8 mm at the 95 % level of confidence without use of complex stereoplotting equipment. Metal reference markers are placed in the shaft of the femur and in the acetabular region of the pelvis at the time of surgery. The distances between these reference markers and certain unambiguous points on the prostheses are computed analytically using an X-Y acoustical digitizer (accuracy ± 0.1 mm) and software developed previously for craniofacial measurement. Separate stereopairs of the joint region are taken under weight-bearing and nonweight-bearing conditions. Differences in the measured distances between the bo-ne markers and the prosthetic components on the two stereopairs are taken as indicators of prosthesis loosening. Measurements on a phantom using ten different x-ray stereopairs taken from as many different perspectives have established that true linear distances between reference points and prostheses can be measured at the desired reliability with the present low precision system. Preliminary in vivo measurements indicate that the main unresolved problem is the movement of the subject between the two exposures of each single stereopair. Two possible solutions to this problem are discussed.

  19. SU-F-T-374: Dosimetric Effects of Irradiation Through a Bilateral Hip Prosthesis in a MRI Linac

    Energy Technology Data Exchange (ETDEWEB)

    Wronski, M; Sarfehnia, A; Sahgal, A; Keller, B [Sunnybrook Odette Cancer Center, Toronto (Canada); University of Toronto, Department of Radiation Oncology, Toronto (Canada); Ahmad, S [Sunnybrook Odette Cancer Center, Toronto (Canada)

    2016-06-15

    Purpose: To evaluate the interface effects when irradiating through a hip prosthesis in the presence of an orthogonal 1.5 T magnetic field using Monte Carlo simulations. Methods: A 20×20×38 cm virtual phantom with two 5×5×5 cm sections of bilateral titanium hip prosthesis was created in GPU-based Monte Carlo (MC) algorithm (GPUMCD, Elekta AB, Stockholm Sweden). The lateral prosthesis spacing was based on a representative patient CT scan. A treatment SAD of 143.5 cm was chosen, corresponding to the Elekta AB MRI Linac and the beam energy distribution was sampled from a histogram representing the true MRI Linac spectrum. A magnetic field of 1.5 T was applied perpendicular to the plane of irradiation. Dose was calculated, in voxels of side 1 mm, for 2×2, 5×5, and 10×10 cm treatment field sizes with normal beam incidence (gantry at 90° or 270°) and at 5° and 10° from normal, representing the range of incidence through the bilateral prosthesis. Results: With magnetic field ON (B-On) and normal beam incidence the backscatter dose at the interfaces of proximal and distal implants is reduced for all the field sizes compared to the magnetic field OFF (B-Off) case. The absolute reduction in doses at the interface was in the range of 12.93% to 13.16% for the proximal implant and 13.57% to 16.12% for the distal implant. Similarly for the oblique incidences of 5o and 10o the dose in the plane adjacent to the prosthetic implants is lower when the magnetic field is ON. Conclusion: The dosimetric effects of irradiating through a hip prosthesis in the presence of a transverse magnetic field have been determined using MC simulation. The backscatter dose reduction translates into significantly lower hot spots at the prosthetic interfaces, which are otherwise substantially high in the absence of the magnetic field. This project was supported through funding provided by ElektaTM.

  20. SU-F-T-374: Dosimetric Effects of Irradiation Through a Bilateral Hip Prosthesis in a MRI Linac

    International Nuclear Information System (INIS)

    Wronski, M; Sarfehnia, A; Sahgal, A; Keller, B; Ahmad, S

    2016-01-01

    Purpose: To evaluate the interface effects when irradiating through a hip prosthesis in the presence of an orthogonal 1.5 T magnetic field using Monte Carlo simulations. Methods: A 20×20×38 cm virtual phantom with two 5×5×5 cm sections of bilateral titanium hip prosthesis was created in GPU-based Monte Carlo (MC) algorithm (GPUMCD, Elekta AB, Stockholm Sweden). The lateral prosthesis spacing was based on a representative patient CT scan. A treatment SAD of 143.5 cm was chosen, corresponding to the Elekta AB MRI Linac and the beam energy distribution was sampled from a histogram representing the true MRI Linac spectrum. A magnetic field of 1.5 T was applied perpendicular to the plane of irradiation. Dose was calculated, in voxels of side 1 mm, for 2×2, 5×5, and 10×10 cm treatment field sizes with normal beam incidence (gantry at 90° or 270°) and at 5° and 10° from normal, representing the range of incidence through the bilateral prosthesis. Results: With magnetic field ON (B-On) and normal beam incidence the backscatter dose at the interfaces of proximal and distal implants is reduced for all the field sizes compared to the magnetic field OFF (B-Off) case. The absolute reduction in doses at the interface was in the range of 12.93% to 13.16% for the proximal implant and 13.57% to 16.12% for the distal implant. Similarly for the oblique incidences of 5o and 10o the dose in the plane adjacent to the prosthetic implants is lower when the magnetic field is ON. Conclusion: The dosimetric effects of irradiating through a hip prosthesis in the presence of a transverse magnetic field have been determined using MC simulation. The backscatter dose reduction translates into significantly lower hot spots at the prosthetic interfaces, which are otherwise substantially high in the absence of the magnetic field. This project was supported through funding provided by ElektaTM.

  1. Bone mineral density after implantation of a femoral neck hip prosthesis--a prospective 5 year follow-up.

    Science.gov (United States)

    Steens, Wolfram; Boettner, Friedrich; Bader, Rainer; Skripitz, Ralf; Schneeberger, Alberto

    2015-08-12

    Bone resorption in the proximal femur due to stress shielding has been observed in a number of conventional cementless implants used in total hip arthroplasty. Short femoral-neck implants are claiming less interference with the biomechanics of the proximal femur. The goal of this study was to prospectively investigate the in vivo changes of bone-mineral density as a parameter of bone remodeling around a short, femoral neck prosthesis over the first 5 years following implantation. The secondary goal was to report on its clinical outcome. We are reporting on the changes of bone mineral density of the proximal femur and the clinical outcome up to five years after implantation of a short femoral neck prosthesis. Bone mineral density was determined using dual energy x-ray absorptiometry, performed 10 days, three, 12 and 60 months after surgery. 20 patients with a mean age of 47 years (range 17 to 65) were clinically assessed using the Harris Hip Score. The WOMAC was used as a patient-relevant outcome-measure. In contrast to conventional implants DEXA-scans overall revealed a slight increase of bone mineral density in the proximal femur in the 12 months following the implantation. The Harris Hip Score improved from an average preoperative score of 46 to a postoperative score at 12 months of 91 points and 95 points at 60 months, the global WOMAC index from 5.3 preoperatively to 0.8 at 12 months and 0.6 at 60 months postoperatively. At 60 months after implantation of a short femoral neck prosthesis, all regions except one (region of interest #5) showed no significant changes in BMD compared to baseline measurements at 10 days which is less to the changes in bone mineral density seen in conventional implants.

  2. Acute Delayed or Late Infection of Revision Total Hip Arthroplasty Treated with Debridement/Antibiotic-loaded Cement Beads and Retention of the Prosthesis

    OpenAIRE

    Chang, Jun-Dong; Kim, In-Sung; Lee, Sang-Soo; Yoo, Je-Hyun

    2017-01-01

    Purpose The treatment of infected revision total hip arthroplasty (THA) is very challenging due to retained revision prosthesis, poor bone stock and soft tissue condition derived from previous revision surgeries, and comorbidities. The purpose of this study was to investigate the effectiveness and short-term outcomes of aggressive debridement and use of antibiotic-loaded cement beads with retention of the prosthesis for acute delayed or late infection of revision THAs. Materials and Methods T...

  3. Biomechanical evaluation of two types of short-stemmed hip prostheses compared to the trust plate prosthesis by three-dimensional measurement of micromotions.

    Science.gov (United States)

    Fottner, Andreas; Schmid, Markus; Birkenmaier, Christof; Mazoochian, Farhad; Plitz, Wolfgang; Volkmar, Jansson

    2009-06-01

    Stemless and short-stemmed hip prostheses have been developed to preserve femoral bone stock. While all these prostheses claim a more or less physiological load transfer, clinical long-term results are only available for the stemless thrust plate prosthesis. In this study, the in vitro primary stability of the thrust plate prosthesis was compared to two types of short-stemmed prostheses. In addition to the well-established Mayo prosthesis, the modular Metha prosthesis was tested using cone adapters with 130 degrees and 140 degrees neck-shaft-angles. The prostheses were implanted in composite femurs and loaded dynamically (300-1700 N). Three-dimensional micromotions at the bone-prosthesis interface were measured. In addition, the three-dimensional deformations at the surface of the composite femur were measured to gain data on the strain distribution. For all tested prostheses, the micromotions did not exceed 150 microm, the critical value for osteointegration. The thrust plate prosthesis revealed similar motions as the short-stemmed prostheses. The short-stemmed prosthesis with the 130 degrees cone tended to have the highest micromotions of all tested short-stemmed prostheses. The thrust plate prosthesis revealed the lowest alteration of bone surface deformation after implantation. The comparably low micromotions of the thrust plate prosthesis and the short-stemmed prostheses should be conducive to osseous integration. The higher alteration of load transmission after implantation reveals a higher risk of stress shielding for the short-stemmed prostheses.

  4. [Clinical evaluation of the hip joint after implantation of cementless Mittelmeier type and Parhofer-Mönch type hip prosthesis].

    Science.gov (United States)

    Grzegorzewski, A; Synder, M; Witoński, D

    2000-01-01

    Total hip replacement is the most common procedure in the treatment of severe degenerative changes in the hip joint. The authors present clinical evaluation of 129 patients (151 hips) who underwent total hip replacement using either the Mittelmeier type or the Parhofer-Mönch type hip prothesis. The age of the patients ranged at the time of the operation between 17 and 74 years (average 44.9). The follow-up ranged from 24 to 143 months (average 61.2 months). The P-M prothesis was implanted in 53 hips, the P-M "Plasmapore" prothesis in 42 patients, Mittelmeier Autophor 900 prothesis in 49 patients and the Mittelmeier Autophor 900S prothesis in 7 patients. Clinical evaluation was performed according to the d'Aubigne-Postel method with the Charnley modification. The results were graded as very good in 17 cases, good in 64 cases, satisfactory in 53 cases and poor in 17 cases. Very good and good results were mainly observed after implantation of the P-M type prothesis and P-M "Plasmapore" type prothesis. Worse results were observed in patients, who at the time of the operation were aged 45 years or less and who had congenital hip dysplasia. P-M type prothesis gives better clinical results in the treatment of degenerative changes of the hip joint.

  5. Primary total hip arthroplasty in Catalonia: What is the clinical evidence that supports our prosthesis?

    Science.gov (United States)

    Chaverri-Fierro, D; Lobo-Escolar, L; Espallargues, M; Martínez-Cruz, O; Domingo, L; Pons-Cabrafiga, M

    The implementation of National Prostheses Registries allows us to obtain a large amount of data and make conclusions in order to improve the use of them. Sweden was the first country to implement a National Prostheses Registry in 1979. Catalonia has been doing this since 2005. The aim of our study is to analyse the evidence that supports primary total hip replacement in Catalonia in the last 9 years, based on the Arthroplasty Registry of Catalonia (RACat). A review of the literature was carried out of the prosthesis (acetabular cups/stems) reported in the RACat between the period 2005 to 2013 in the following databases: ODEP (Orthopaedic Data Evaluation Panel), TRIP database, PubMed, and Google Scholar. Those prostheses implanted in less than 10 units (182 acetabular components corresponding to 49 models/228 stems corresponding to 63 models) were excluded. A total of 18,634 (99%) implanted acetabular cups were analysed out of a total number of 18,816, corresponding to 74 different models. In 18 models (2527 acetabular cups) no clinical evidence to support its use was found. An analysis was performed on 19,367 (98.84%) out of a total number of 19,595 implanted stems, corresponding to 75 different models. In 16 models (1845 stems) no clinical evidence was found to support their use. Variable evidence was found in the 56 models of acetabular cups (16,107) and 59 models of stems (17,522), most of it corresponding to level iv clinical evidence. There was a significant number implanted prostheses evaluated (13.56% acetabular cups/9.5% stems) for which no clinical evidence was found. The elevated number of models is highlighted (49 types for acetabular cups/63 types for stems) with less than 10 units implanted, which corresponds to only 1% of the total implants. The use of arthroplasty registers is shown to be an extremely helpful tool that allows analyses and conclusions to be made for the follow-up and post-marketing surveillance period. Copyright © 2016 SECOT

  6. Metallosis: A diagnosis not only in patients with metal-on-metal prostheses

    International Nuclear Information System (INIS)

    Oliveira, Catarina A.; Candelária, Isabel S.; Oliveira, Pedro B.; Figueiredo, Antonio; Caseiro-Alves, Filipe

    2014-01-01

    Although the real actual incidence of metallosis is unknown, it is described as a rare diagnosis with a 5% estimated incidence in the hip prosthetic replacements. The adoption of non-metallic articular prosthetic devices, made of polyethylene and ceramic, is the main reason to the diminishing number of reported cases. We present a case of metallosis with a clinical systemic presentation in a patient with a non-metallic hip prosthesis, which occurred due to a fracture of the acetabular liner component, leading to abnormal metal–metal contact. The metallic debris leads to a massive local and systemic release of cytokines. Revision is necessary whenever osteolysis and loosening of the prosthesis occur. Imaging evaluation, especially CT, has a central role in diagnosis and planning the surgical treatment

  7. Use of hip and knee clinical scoring systems in prosthesis surgery in Norwegian hospitals

    OpenAIRE

    Stavem, Knut; Arnesen, Øyvind

    2005-01-01

    In a postal survey of all orthopaedic surgery departments performing total hip or knee replacements in Norway, we inquired about the use of hip or knee scoring systems and their impact. All 63 eligible hospitals responded to the questionnaire. Thirteen (21%) reported routine use of hip clinical scoring systems, and five (9%) used knee clinical scoring systems. The Harris hip score and The Knee Society clinical rating system were the most prevalent. We received five different versions of the H...

  8. The thrust plate prosthesis in the treatment of osteoarthritis of the hip. Clinical and radiological outcome with minimum 5-year follow-up.

    Science.gov (United States)

    Corner, J A; Rawoot, A; Parmar, H V

    2008-01-01

    The thrust plate prosthesis (TPP) is a neck preserving femoral component in total hip arthroplasty (THA). We present our mid-term results from using the thrust plate prosthesis in young patients with hip arthritis. We conducted a retrospective review of a consecutive series of patients with a minimum of 5 years follow-up after total hip arthroplasty using the thrust plate prosthesis. Harris Hip Score (HHS) and Oxford Hip Score (OHS) were recorded preoperatively and at the last clinical review. Radiographic analysis was performed and patient satisfaction levels and complications were recorded. Between 1996 and 2000 we implanted 41 prostheses in 38 consecutive patients (3 bilateral). The mean age at time of surgery was 56 years (41-67) and the mean length of follow-up was 71 months. The HHS improved from a mean of 42 points preoperatively to 88 points at the last clinical review and the mean OHS also improved from 40 points to 18 points. Eighty-three percent of patients expressed that they were 'very satisfied' with the procedure. Implant survivorship was 95% at 5 years follow-up with revision surgery being the end point. Eight patients suffer discomfort when lying on the operated side. Many patients treated with the TPP show excellent improvement in clinical outcome scores and a high level of patient satisfaction but the complication rate gives some concern. We support the selective use of the TPP to treat young patients with hip osteoarthritis.

  9. Artifact Reduction in X-Ray CT Images of Al-Steel-Perspex Specimens Mimicking a Hip Prosthesis

    Science.gov (United States)

    Madhogarhia, Manish; Munshi, P.; Lukose, Sijo; Subramanian, M. P.; Muralidhar, C.

    2008-09-01

    X-ray Computed Tomography (CT) is a relatively new technique developed in the late 1970's, which enables the nondestructive visualization of the internal structure of objects. Beam hardening caused by the polychromatic spectrum is an important problem in X-ray computed tomography (X-CT). It leads to various artifacts in reconstruction images and reduces image quality. In the present work we are considering the Artifact Reduction in Total Hip Prosthesis CT Scan which is a problem of medical imaging. We are trying to reduce the cupping artifact induced by beam hardening as well as metal artifact as they exist in the CT scan of a human hip after the femur is replaced by a metal implant. The correction method for beam hardening used here is based on a previous work. Simulation study for the present problem includes a phantom consisting of mild steel, aluminium and perspex mimicking the photon attenuation properties of a hum hip cross section with metal implant.

  10. Numerical analysis of the biomechanical complications accompanying the total hip replacement with NANOS-Prosthetic: bone remodelling and prosthesis migration

    Directory of Open Access Journals (Sweden)

    Almohallami A.

    2015-09-01

    Full Text Available Aseptic loosening of the prosthesis is still a problem in artificial joint implants. The ýloosening can be caused by the resorption of the bone surrounding ýthe prosthesis according to stress shielding. A numerical model was developed and validated by means of DEXA-studies in order to ýanalyse the bone remodelling process in the periprosthetic bone. A total loss of about 3.7% of the bone density in the periprosthetic Femur with NANOS is computed. The bone remodelling calculation was validated by means of a DEXA-study with a 3-years-follow-up. The model was further developed in order to be able to calculate and consider the migration of the implants. This method was applied on the ýNANOS-implant with a computed total migration of about 0.43 mm. These calculations showed good results in comparison with a 2-year-follow-up clinical study, whereby a RSA-method was used to determine the stem migration in the bone. In order to ýstudy the mutual influence between the implant migration and the hip contact forces ý, a software is developed by our scientific group to couple a multi body simulation (MBS of human lower limps with the FEA of the periprosthetic Femur.

  11. Morphological experimental study of bone stress at the interface acetabular bone/prosthetic cup in the bipolar hip prosthesis.

    Science.gov (United States)

    Anuşca, D; Pleşea, I E; Iliescu, N; Tomescu, P; Poenaru, F; Dascălu, V; Pop, O T

    2006-01-01

    By calculating the tension and distortion of the elements composing the bipolar prosthesis under extreme conditions encountered in real life using a special post-processing program, we established the variation curves of the contact pressure at the hip bone-cup, armor-cup and cup-femoral head interface. By comparing the data obtained from all the examined cases, important conclusions were drawn regarding the influence of tension and pressure distribution on the structural integrity and biomechanics of the prosthesis, as well as the acetabular wear and tear, in order to assess its reliability. The experimentally determined tension and distortion status at the acetabular bone-metal armour interface, lead to the wear and tear phenomenon, which can be explained by three mechanisms and theories incompletely reflecting the overall process. The histopathologic study of the acetabular bone tissue using FEM (finite elements method) on surgically removed specimens will probably lead to the identification of a series of factors that could reduce the rate of the wear and tear process.

  12. Influence of stem type on material loss at the metal-on-metal pinnacle taper junction.

    Science.gov (United States)

    Hothi, Harry S; Whittaker, Robert K; Meswania, Jay M; Blunn, Gordon W; Skinner, John A; Hart, Alister J

    2015-01-01

    The clinical importance of material loss at the head-stem junction is unknown. Comparison of retrievals with different stem types can provide the opportunity to understand the importance of the taper junction. This was a case-control study involving 20 retrieved 36 mm metal-on-metal Pinnacle (DePuy) hips that were paired with either a Corail (n = 10) or S-ROM (n = 10) stem. The median head taper material loss rate for the Corail group was 0.238 (0.0002-2.178) mm(3)/year and was significantly greater than the S-ROM group (p = 0.042), which had a median material loss rate of 0.132 (0.015-0.518) mm(3)/year. The only significant difference between the groups was the stem taper roughness and length: this was rougher and shorter for the Corails. Long and smooth stem taper designs are preferred when used in conjunction with metal heads. © IMechE 2015.

  13. Intensity-Modulated Radiation Therapy with Noncoplanar Beams for Treatment of Prostate Cancer in Patients with Bilateral Hip Prosthesis-A Case Study

    International Nuclear Information System (INIS)

    Brooks, Chris; Cheung, Rex Min; Kudchadker, Rajat J.

    2010-01-01

    Megavoltage photon intensity-modulated radiation therapy (IMRT) is typically used in the treatment of prostate cancer at our institution. Approximately 1% to 2% of patients with prostate cancer have hip prostheses. The presence of the prosthesis usually complicates the planning process because of dose perturbation around the prosthesis, radiation attenuation through the prosthesis, and the introduction of computed tomography artifacts in the planning volume. In addition, hip prostheses are typically made of materials of high atomic number, which add uncertainty to the dosimetry of the prostate and critical organs in the planning volume. When the prosthesis is bilateral, treatment planning is further complicated because only a limited number of beam angles can be used to avoid the prostheses. In this case study, we will report the observed advantages of using noncoplanar beams in the delivery of IMRT to a prostate cancer patient with bilateral hip prostheses. The treatment was planned for 75.6 Gy using a 7-field coplanar approach and a noncoplanar arrangement, with all fields avoiding entrance though the prostheses. Our results indicate that, compared with the coplanar plan, the noncoplanar plan delivers the prescribed dose to the target with a slightly better conformality and sparing of rectal tissue versus the coplanar plan.

  14. Factors governing the healing of Staphylococcus aureus infections following hip and knee prosthesis implantation: a retrospective study of 95 patients.

    Science.gov (United States)

    Joulie, D; Girard, J; Mares, O; Beltrand, E; Legout, L; Dezèque, H; Migaud, H; Senneville, E

    2011-11-01

    The prognostic factors for total hip arthroplasty (THA) and total knee arthroplasty (TKA) Staphylococcus aureus prosthetic joint infections are poorly known, notably because of the heterogeneous management in terms of both antibiotic administration and adopted surgical strategy. Uniform treatment regimens would make it easier to define the outcome of these S. aureus infections. Between 2001 and 2006, 95 patients with a S. aureus joint infection after THA or TKA were treated, strictly following a standardized protocol according to the recommendations of Zimmerli et al. The patients' mean age was 65.7 years, 71 with THA and 28 with TKA (four patients had two infected joints). These 95 patients presented 120 infectious episodes, all of whom had surgical treatment: 53 lavages (44.1%), 17 one-stage prosthesis revisions (14.2%), 29 two-stage prosthesis revisions (24.2%), and 21 prostheses removed (17.5%). On the intraoperative samples taken, methicillin-sensitive S. aureus (MSSA) was isolated in 88 patients (73.3%) and methicillin-resistant S. aureus (MRSA) in 18 patients (15%); finally 14 patients were included because of the positive results of preoperative samples taken. Twenty-seven infections (22.5%) were multibacterial, including at least S. aureus and 93 were single S. aureus bacteria. Success was defined at a minimum 12 months of follow-up by the association of the following parameters: normal erythrocyte sedimentation rate (ESR) and/or C-reactive protein (CRP) results, noninflammatory scar with no fistula, no surgical revision, and no antibiotic treatment. At a mean follow-up of 38±24.9 months, 81 of the 120 infectious episodes were resolved (67.5%) and 77 of the 95 patients were healed (81%). Six parameters significantly influenced the healing of the infection: initial cementless fixation, THA, preoperative knowledge of the bacterium, immediate postoperative antibiotic therapy adapted to the microbiological data, changing the prosthesis, and monobacterial

  15. [Medium-term results of the Mayo™ short-stem hip prosthesis after avascular necrosis of the femoral head].

    Science.gov (United States)

    Zeh, A; Weise, A; Vasarhelyi, A; Bach, A G; Wohlrab, D

    2011-04-01

    Short-stemmed prostheses are increasingly regarded as implants of first choice in coxarthrosis, especially in young patients. Despite promising short-term results, long-term follow-up studies are still lacking. Short-stemmed femoral implants are characterised by a metaphyseal osseointegration and strain distribution. Therefore a reduced stress shielding of the proximal femur is hypothesized and in some studies already proven. There is histological evidence that osteonecrosis (ON) of the femoral head may involve not only the intracapital region but also the femoral neck and metaphyseal area. This could lead to a higher rate of aseptic loosening of short-stemmed implants. The aim of this retrospective study was to analyze the midterm results of the Mayo™ short-stem prosthesis after ON with particular attention on osseointegration. From 2002-2004, in 21 patients (2 females, 19 males; mean age 45 years; mean BMI = 27) with secondary coxarthrosis after ON implantation of 26 Mayo™ Conservative Hips was performed. Postoperatively, all patients were mobilised with full weight-bearing. Using the specially developed Wristing® software, longitudinal stem migration and varus-valgus femoral stem alignment were examined digitally in anteroposterior X-rays taken immediately after surgery and in standing AP radiographs after 8.2 months and on average after 7.9 years (16 patients). The incidence of periprosthetic radiolucent lines was captured in the anteroposterior X-rays and assigned to the Gruen zones and a DEXA scan was performed. The X-rays of a matched control group with implantation of a Mayo™ short-stem prosthesis in primary coxarthrosis were analyzed by the same method. In all patients the Harris hip score (HHS) was obtained pre- and postoperatively. There was no significant migration or valgus tilt of the Mayo™ prosthesis in the study and control groups during postoperative follow-up (paired t-test, p = 0.13 and 0.69, respectively). In six of 26 Mayo™-Stems 12

  16. Tribology of total hip arthroplasty prostheses

    Science.gov (United States)

    Rieker, Claude B.

    2016-01-01

    Articulating components should minimise the generation of wear particles in order to optimize long-term survival of the prosthesis. A good understanding of tribological properties helps the orthopaedic surgeon to choose the most suitable bearing for each individual patient. Conventional and highly cross-linked polyethylene articulating either with metal or ceramic, ceramic-on-ceramic and metal-on-metal are the most commonly used bearing combinations. All combinations of bearing surface have their advantages and disadvantages. An appraisal of the individual patient’s objectives should be part of the assessment of the best bearing surface. Cite this article: Rieker CB. Tribology of total hip arthroplasty prostheses: what an orthopaedic surgeon should know. EFORT Open Rev 2016;1:52-57. DOI: 10.1302/2058-5241.1.000004. PMID:28461928

  17. Mechanical analysis of ceramic heat being part of hip prosthesis with presence of cracks

    International Nuclear Information System (INIS)

    Ravagli, E.

    1995-03-01

    This report still pursues the aim of carrying out a systematic mechanical analysis of a ceramic heat being part of a modular hig prosthesis, in order to characterize it exhaustively, i. e. to assess its performances and some of its main specifications. A mechanical analysis of a second case is carried out here, the presence of head cracks being taken into account. The evaluations made lead to the conclusion that the head should not show cracks bigger than 100 mm. This study is performed in the frame of the STRIDE-CETMA project, which is aimed at founding and developing a centre for technologically advanced materials in Brindisi technology park (Italy)

  18. Locking compression plate versus revision-prosthesis for Vancouver type B2 periprosthetic femoral fractures after total hip arthroplasty.

    Science.gov (United States)

    Joestl, Julian; Hofbauer, Marcus; Lang, Nikolaus; Tiefenboeck, Thomas; Hajdu, Stefan

    2016-04-01

    Revision arthroplasty is currently the recommended treatment for periprosthetic femoral fractures after primary total hip arthroplasty (THA) and stem loosening (Vancouver B2). However, open reduction and internal fixation (ORIF) utilizing locking compression plate (LCP) might be an effective treatment with a reduced surgical time and less complex procedure in a typically elderly patient collective with multiple comorbidities. The purpose of this study was to compare the functional and radiographic outcomes in two cohorts with Vancouver B2 periprosthetic femoral fractures after primary THA, treated either by ORIF with LCP fixation, or by revision arthroplasty utilizing a non-cemented long femoral stem. 36 patients with Vancouver B2 periprosthetic femoral fractures following THA, who had been treated between 2000 and 2014, were reviewed. Eight fractures were treated with LCP fixation, fourteen fractures with the first-generation revision prosthesis (Helios), and fourteen fractures with the second-generation revision prosthesis (Hyperion). The patients were assessed clinically with the Parker mobility score and radiographically. A total of ten males and 26 females formed the basis of this report with an average age of 81 years (range, 64 to 96 years). All fractures treated with LCP fixation alone healed uneventfully and there were no signs of secondary stem migration, malalignement or plate breakage. The average surgical time was shorter in the ORIF cohort; however, the results were not statistically significant. The postoperative Parker mobility score at latest follow-up showed no difference between the groups. According to the results of the current study, we conclude that the use of LCP fixation can be a sufficient option for the treatment of Vancouver B2 periprosthetic femoral fractures correspondingly with femoral stem loosening. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Results of endoprosthetic hip joint replacement with the aluminum ceramic-metal composite prosthesis "Lindenhof".

    Science.gov (United States)

    Stock, D; Diezemann, E D; Gottstein, J

    1980-01-01

    The first clinical results of the Lindenhof ceramic-metal composite prosthesis implanted in our hospital in Freiburg are presented. We observed that same favorable early results as the conventional prostheses in a correct position. The implants are incorporated into the bone within 8-12 weeks. The radiographic films show the adaptation of the supporting bone around the ceramic socket. We explain the failures due to our initial lack of technical experience and/or anatomical deformation of the pelvic bone. complications caused by the post-operative treatment during the 12 weeks following surgery did not occur. The combination of a cemented metal femoral component with a ceramic head seems to be a reasonable compromise to use the favorable physical and biochemical properties of the bioceramic material as long as there is no satisfactory solution for a stable cementless fixation of the femoral stem in to the bone. The advantages of the Lindenhof prosthesis predominate the disadvantages: expensive instruments and a post-operative treatment of several months.

  20. [Modified mini-Hardinge access for hip prosthesis implantation in the supine position].

    Science.gov (United States)

    Mazoochian, F; Schmidutz, F; Fottner, A; Jansson, V

    2014-04-01

    Total hip arthroplasty with a minimal-incision technique that can be performed in the widely used supine position. The accustomed and good overview of this position allows safe positioning of the implant and combines this with the advantage of a soft tissue preserving technique. All standard instruments and implants can be further applied. Primary and secondary coxarthrosis, femoral head necrosis. Revision surgery, severe anatomic deformity, implantation of hip resurfacing arthroplasty. Supine position. The skin incision runs from the innominate tubercle proximally and falls slightly in the dorsal direction (20-30°). Incision of the iliotibial tract and exposure of the vastogluteal muscle sling. Starting from the greater trochanter, the sinewy onset of the minimal and medium gluteal muscle is split with an arched-shaped incision, which also falls proximally in the dorsal direction. Exposition of the joint capsule, longitudinal incision and resection of the ventrolateral parts. Dislocation of the hip by a combined adduction and external rotation movement. Osteotomy of the femoral neck and resection of the femoral head are performed in a figure-of-four position without adduction. To prepare the acetabulum and to insert the cup, the leg is placed in neutral position with a slight flexion of 20° in the hip. Preparation of the femur and implantation of the stem is again performed in a figure-of-four position in adduction. Reduction of the hip and stepwise wound closure. Mobilization on postoperative day 1. Starting with half weight bearing and after completed wound healing rapid increase to full weight bearing. Intensive physiotherapy and rehabilitation. Thrombosis prophylaxis according to guidelines. The mini-incision approach has successfully been used in our clinic for years. Between September 2004 and November 2005, the less-invasive technique was evaluated in a randomized controlled trial with 51 patients (52 hips). Compared to the standard approach a

  1. Finite element analysis of 2-Station hip himulator

    Science.gov (United States)

    Fazli, M. I. M.; Yahya, A.; Shahrom, A.; Nawawi, S. W.; Zainudin, M. R.; Nazarudin, M. S.

    2017-10-01

    This paper presented the analysis of materials and design architecture of 2-station hip simulator. Hip simulator is a machine used to conduct the joint and wear test of hip prosthetic. In earlier work, the hip simulator was modified and some improvement were made by using SolidWorks software. The simulator consists of 3DOF which controlled by separate stepper motor and a static load that set up by manual method in each station. In this work, finite element analysis (FEA) of hip simulator was implemented to analyse the structure of the design and selected materials used for simulator component. The analysis is completed based on two categories which are safety factor and stress tests. Both design drawing and FEA was done using SolidWorks software. The study of the two categories is performed by applying the peak load up to 4000N on the main frame that is embedded with metal-on-metal hip prosthesis. From FEA, the value of safety factor and degree of stress formation are successfully obtained. All the components exceed the value of 2 for safety factor analysis while the degree of stress formation shows higher value compare to the yield strength of the material. With this results, it provides information regarding part of simulator which are susceptible to destruct. Besides, the results could be used for design improvement and certify the stability of the hip simulator in real application.

  2. Impact of UHMWPE texture on friction and wear resistance of hip prosthesis

    Directory of Open Access Journals (Sweden)

    Eddoumy Fatima

    2013-11-01

    Full Text Available Ultra High Molecular Weight PolyEthylene (UHMWPE is a polymer widely used in hip implants (prostheses as a bearing surface against metal, because of its good mechanical properties and biocompatibility [1]. Nevertheless, the durability of such implants is limited because of failure resulting from osteolysis and aseptic loosening. These two phenomenons are due to the immune response of human body consecutive to the apparition of wear particles of UHMWPE with time.

  3. Ultrastructural characterization of soft tissues surrounding implanted hip prosthesis by complementary PIXE and TEM methods

    Science.gov (United States)

    Jallot, E.; Benhayoune, H.; Kilian, L.; Balossier, G.; Bonhomme, P.; Oudadesse, H.; Irigaray, J. L.

    We study soft tissues surrounding hip prostheses from three different patients. We evaluate the elemental composition of different fragments. The tissues are examined by means of two complementary methods in such analysis: Particle Induced X-ray Emission (PIXE) and Scanning Transmission Electron Microscopy (STEM) coupled with X-ray microanalysis (Energy Dispersive X-ray, EDX). These methods allow to determine locally at `macro' and `micro' level the chemistry of soft tissues. The findings confirmed the presence of metal in soft tissue near the three different hips. The tissues' composition undergoes important modifications with a systematic elevation of trace metal in patients with failed implants. We observe a corrosion which causes the continual release of particles into the tissues. Corrosion alters the shape size and chemical composition of wear particles embedded in soft tissue around the failed hip. EDX analysis showed that the wear particles contained varying quantities of titanium and aluminium. This phenomenon may be related with the variation of time of contact with soft tissues for each particle and Ti solubility.

  4. Clinical and radiological results after implantation of the femoral neck preserving Delfi M hip prosthesis: a case series.

    Science.gov (United States)

    Budde, Stefan; Windhagen, Henning; Lerch, Matthias; Broese, Maximilian; Götze, Patricc; Thorey, Fritz

    2012-01-01

    Various types of bone preserving total hip prostheses with a proximal force transmission concept have been developed for younger adults, one of these being the implant "Delfi M®", produced by ESKA until 2009. Since the demand could not meet the expectations, the production was stopped due to economic reasons so that only 31 implants of this type were sold and even less actually implanted. This study followed up 15 Delfi M® prostheses in 12 patients for 3.1 years and represents the only existing valid data about this implant.Demographical, preoperative and postoperative data including clinical scores (HOOS and mHHS) were collected retrospectively. Postoperative X-rays were analyzed by an independent radiologist. One implant had to be exchanged due to an infection and another one due to excessive implant migration. The mHHS and the HOOS scores showed a significant improvement after surgery. In the radiological analysis, there were no signs of radiolucent lines or osteolyses.This trial demonstrates good clinical and radiological midterm results for the Delfi M prosthesis. Limitations of this study are a small sample size and a follow-up time of 3 years at only one timepoint. © 2012 – IOS Press and the authors. All rights reserved

  5. Personalized image-based templates for precise acetabular prosthesis placement in total hip arthroplasty: a pilot study

    Science.gov (United States)

    Chen, Bin; Xiao, Sheng-xiang; Gu, Peng-cheng; Lin, Xiang-jin

    2010-01-01

    Objective: In order to achieve accurate implantation of the acetabular prosthesis in total hip arthroplasty (THA), we designed individual templates based on a three-dimensional (3D) model generated from computed tomography (CT) scans. Methods: Individual templates were designed for 12 patients who underwent THA. A physical template was designed to conform to the contours of the patient’s acetabulum and to confirm the rotation of the acetabular center. This guided the acetabular component orientation. Results: The preoperative and postoperative X-ray and CT scans were obtained to assess the location with respect to the accuracy of the acetabular component. For all patients, the abduction angle of the acetabular component was 46.7° to 54.3° and the anteversion angle was 11.3° to 18.5°. Conclusions: The assessment of postoperative CT scans demonstrated higher accuracy of the acetabular component bore when used with the individual template. Therefore, the individual template can be an alternative to the computer-assisted navigation systems, with a good cost-performance ratio. PMID:20803771

  6. Assessments of different kinds of stems by experiments and FEM analysis: appropriate stress distribution on a hip prosthesis.

    Science.gov (United States)

    Sakai, Rina; Itoman, Moritoshi; Mabuchi, Kiyoshi

    2006-10-01

    It is now recognized that initial stability is essential for avoidance of thigh pain in hip replacement. The initial stability corresponds to an optimal stress distribution of cementless orthopedic implants. Although the relationship between the contour and stress at the fixation site has been analyzed, guidelines on stem design have not been established. Finite element models of three currently-used stems were constructed for a computer simulation. Contact stress at the fixation site of a joint prosthesis was analyzed by an explicit three-dimensional finite element method. The stress immediately after applying load using a film or sensor which can measure contact stress was observed. The situation of the initial fixation about the specific part which becomes important clinically based on the results was clarified. We introduced fluctuation area as a measure to evaluate the primary fixation of femoral stems. It was found that the stress distribution on the PerFix SV stem fluctuated with a slight disturbance. On the Intra-Medullary Cruciate stem, the high stress areas were distributed on the proximal area and under the pin. The high stress area on the VerSys stem were spread on the medial side. This study highlights the mechanical instability of the fixation site of joint prostheses, and thus suggests that the general idea that unconditionally recommends a larger area for the fixation site of joint prostheses should be revised.

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

    Directory of Open Access Journals (Sweden)

    Aram Luke

    2007-05-01

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

  8. A study of TiN-coated metal-on-polymer bearing materials for hip prosthesis

    Science.gov (United States)

    Lee, Sung Bai; Choi, Jin Young; Park, Won Woong; Jeon, Jun Hong; Won, Sung Ok; Byun, Ji Young; Lim, Sang Ho; Han, Seung Hee

    2010-08-01

    The TiN-coated metal-on-polymer hip prosthetic pair has the potential to reduce wear debris of UHMWPE (ultra-high molecular weight polyethylene) and to prevent metallic-ion-induced cytotoxicity. However, high quality and adherent film is a key to the clinical success of hip prostheses. In this study, titanium nitride (TiN) films were deposited on stainless steel using plasma immersion ion implantation & deposition (PIII&D) technique to create high-quality film and an adherent interface. The chemical state and composition were analyzed by X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and energy dispersive spectroscopy (EDS). The mechanical properties of the films were characterized using a micro-hardness tester and a pin-on-disk wear tester, and an x-ray diffractometer (XRD) was used for a crystallographic analysis. The PIII&D-treated TiN films showed a stoichiometric and (200) preferred orientation and micro-hardness up to 150 % higher than untreated film. A TiN-coated specimen using the PIII&D process also showed less UHMWPE wear compared to untreated specimens. The volumetric wear rate of UHMWPE could be reduced by as much as 42 % compared to when Co-Cr alloy was used. The results of this study show that advanced TiN-coating via the PIII&D process is a viable means of reducing UHMWPE wear in the metal-on-polymer bearing couple.

  9. Door to relocation time for dislocated hip prosthesis: multicentre comparison of emergency department procedural sedation versus theatre-based general anaesthesia.

    Science.gov (United States)

    Gagg, J; Jones, L; Shingler, G; Bothma, N; Simpkins, H; Gill, S; Benger, J; Lloyd, G

    2009-01-01

    Dislocation of a hip prosthesis is a painful event which has an incidence of 4% for primary total hip arthroplasty. Relocation is traditionally performed under general anaesthesia in the operating theatre, but relocation using sedation in the emergency department (ED) has been reported, with a limited success rate of 62%. A study was undertaken to compare door to relocation times for ED sedation and theatre general anaesthesia. The notes of all patients attending five centres in the south west of England with prosthetic hip dislocation over a 12-month period between 2005 and 2006 were retrospectively reviewed using standardised data collection forms. Successful ED reduction was significantly quicker than failed ED reduction and theatre-based general anaesthesia (2 h 21 min vs 8 h 32 min; phip prostheses in the ED saves nearly 6 h compared with theatre-based general anaesthesia and is therefore advocated.

  10. [Cement-free and cemented Excia hip shaft prosthesis: comparison of intermediate term results].

    Science.gov (United States)

    Urschel, C; Döring, M; Strecker, W

    2014-09-01

    For fixation of total hip prostheses, cemented and cement-free techniques are available. Normally, anchoring techniques and the definitive endoprosthesis model are determined preoperatively based on the available information, such as the quality of bone. Some newer endoprosthesis models utilize the same instruments for both implantation techniques. In this way it is possible to decide on the final anchoring technique intraoperatively. Because such a combined endoprosthesis system has been used in our clinic for 10 years, we were interested in the clinical results at the intermediate stage. In a prospective, non-randomized study 105 pairs from a continuing series were formed from 105 cases treated with cement-free prostheses and the latest cemented shaft implants from the same year. In this way a total of 210 hip shaft endoprostheses from the years 2002 to 2006 were included in the study. After an average time period of 6.3 years (range 4.5-8.2 years) the patients were recalled for a follow-up examination. The clinical results, early and late complications were analyzed. The immediately postoperative X-ray images and those from the follow-up examination were evaluated by an independent external expert with respect to primary positioning, migration and any signs of loosening. At the follow-up examination at an average of 6.3 years the quota was 73%. The indications for cement-free/cemented total hip endoprosthesis were: primary arthritis 87%/98%, secondary arthritis 10%/2% and others 3%/0%. At the time of the last follow-up examination 4 and 14 patients, respectively, had died. The visual analog scale (VAS) for pain was given as 0.72/0.78. The Harris hip score improved from 54/48 to 93/90 points. The implant-related survival rate was 99.5%. Due to a periprosthetic fracture one of the cemented shafts had to be removed. Luxation occurred in 3/2 cases, respectively, of which 4 could be conservatively treated. In one cement-free case a head elongation and a change to an

  11. Good results in postoperative and hematogenous deep infections of 89 stable total hip and knee replacements with retention of prosthesis and local antibiotics

    Science.gov (United States)

    2013-01-01

    Background Deep postoperative and hematogenous prosthesis infections may be treated with retention of the prosthesis, if the prosthesis is stable. How long the infection may be present to preclude a good result is unclear. Patients and methods We retrospectively studied 89 deep-infected stable prostheses from 69 total hip replacements and 20 total knee replacements. There were 83 early or delayed postoperative infections and 6 hematogenous. In the postoperative infections, treatment had started 12 days to 2 years after implantation. In the hematogenous infections, symptoms had been present for 6 to 9 days. The patients had been treated with debridement, prosthesis retention, systemic antibiotics, and local antibiotics: gentamicin-PMMA beads or gentamicin collagen fleeces. The minimum follow-up time was 1.5 years. We investigated how the result of the treatment had been influenced by the length of the period the infection was present, and by other variables such as host characteristics, infection stage, and type of bacteria. Results In postoperative infections, the risk of failure increased with a longer postoperative interval: from 0.2 (95% CI: 0.1–0.3) if the treatment had started ≥ 4 weeks postoperatively to 0.5 (CI: 0.2–0.8) if it had started at ≥ 8 weeks. The relative risk for success was 0.6 (CI: 0.3–0.95) if the treatment had started ≥ 8 weeks. In the hematogenous group, 5 of 6 infections had been treated successfully. Interpretation A longer delay before the start of the treatment caused an increased failure rate, but this must be weighed against the advantage of keeping the prosthesis. We consider a failure rate of prosthesis for up to 8 weeks postoperatively, and in hematogenous infections with a short duration of symptoms. PMID:24171687

  12. Good results in postoperative and hematogenous deep infections of 89 stable total hip and knee replacements with retention of prosthesis and local antibiotics.

    Science.gov (United States)

    Geurts, Jan A P; Janssen, Daniël M C; Kessels, Alfons G H; Walenkamp, Geert H I M

    2013-12-01

    Deep postoperative and hematogenous prosthesis infections may be treated with retention of the prosthesis, if the prosthesis is stable. How long the infection may be present to preclude a good result is unclear. We retrospectively studied 89 deep-infected stable prostheses from 69 total hip replacements and 20 total knee replacements. There were 83 early or delayed postoperative infections and 6 hematogenous. In the postoperative infections, treatment had started 12 days to 2 years after implantation. In the hematogenous infections, symptoms had been present for 6 to 9 days. The patients had been treated with debridement, prosthesis retention, systemic antibiotics, and local antibiotics: gentamicin-PMMA beads or gentamicin collagen fleeces. The minimum follow-up time was 1.5 years. We investigated how the result of the treatment had been influenced by the length of the period the infection was present, and by other variables such as host characteristics, infection stage, and type of bacteria. In postoperative infections, the risk of failure increased with a longer postoperative interval: from 0.2 (95% CI: 0.1-0.3) if the treatment had started ≥ 4 weeks postoperatively to 0.5 (CI: 0.2-0.8) if it had started at ≥ 8 weeks. The relative risk for success was 0.6 (CI: 0.3-0.95) if the treatment had started ≥ 8 weeks. In the hematogenous group, 5 of 6 infections had been treated successfully. A longer delay before the start of the treatment caused an increased failure rate, but this must be weighed against the advantage of keeping the prosthesis. We consider a failure rate of prosthesis for up to 8 weeks postoperatively, and in hematogenous infections with a short duration of symptoms.

  13. Friction in total hip joint prosthesis measured in vivo during walking.

    Directory of Open Access Journals (Sweden)

    Philipp Damm

    Full Text Available Friction-induced moments and subsequent cup loosening can be the reason for total hip joint replacement failure. The aim of this study was to measure the in vivo contact forces and friction moments during walking. Instrumented hip implants with Al2O3 ceramic head and an XPE inlay were used. In vivo measurements were taken 3 months post operatively in 8 subjects. The coefficient of friction was calculated in 3D throughout the whole gait cycle, and average values of the friction-induced power dissipation in the joint were determined. On average, peak contact forces of 248% of the bodyweight and peak friction moments of 0.26% bodyweight times meter were determined. However, contact forces and friction moments varied greatly between individuals. The friction moment increased during the extension phase of the joint. The average coefficient of friction also increased during this period, from 0.04 (0.03 to 0.06 at contralateral toe off to 0.06 (0.04 to 0.08 at contralateral heel strike. During the flexion phase, the coefficient of friction increased further to 0.14 (0.09 to 0.23 at toe off. The average friction-induced power throughout the whole gait cycle was 2.3 W (1.4 W to 3.8 W. Although more parameters than only the synovia determine the friction, the wide ranges of friction coefficients and power dissipation indicate that the lubricating properties of synovia are individually very different. However, such differences may also exist in natural joints and may influence the progression of arthrosis. Furthermore, subjects with very high power dissipation may be at risk of thermally induced implant loosening. The large increase of the friction coefficient during each step could be caused by the synovia being squeezed out under load.

  14. [Braking capacity after hip arthroplasty - effect of prosthesis design and preoperative status].

    Science.gov (United States)

    Franz, A; Mannel, H; Brüggemann, G-P; Schmidt, J

    2012-10-01

    Driving a car is an important everyday activity. However, the patients' desire to resume driving at an early stage after hip arthroplasty is often faced by the uncertainty about their driving ability. Only little evidence is available to support the clinical decision-making with regard to driving competence after conventional total hip arthroplasty (THA). However, there is no proof that the results observed after THA can be transferred to hip resurfacing arthroplasty (HRA) patients. Due to physiological advantages, i.e., patient age and activity, as well as the special biomechanical implant characteristics, HRA patients could be expected to achieve normal braking capacity at an earlier stage in the rehabilitation process than THA patients. This could be achieved by an accelerated postoperative recovery or could depend on the preoperative vantage point concerning the patients' braking capacity. To verify this hypothesis HRA and THA patients were compared to healthy subjects concerning their ability to perform an emergency braking manoeuvre in a car simulator before surgery, and at 6 weeks and 3 months after operation. Furthermore, postoperative recovery rates were compared between the two groups of patients. In addition, correlations between pre- and postoperative braking capacity were tested. Reaction time, movement time and force-time integral on the brake pedal were analysed. Except for a deficient preoperative force-time integral, no significant differences were detected in HRA patients compared to healthy controls. In contrast THA patients required, pre- as well as postoperatively, a longer movement time and exhibited a smaller force-time integral. The two patient groups did not show any significant difference in recovery rates of movement time and force-time integral. However, considering the two patient groups as a whole, a significant correlation was detected between existing pre- and postoperative deficits. In conclusion, it can be confirmed that HRA

  15. Total hip prosthesis CT with single-energy projection-based metallic artifact reduction: impact on the visualization of specific periprosthetic soft tissue structures

    Energy Technology Data Exchange (ETDEWEB)

    Gondim Teixeira, Pedro Augusto [CHU-Nancy, Service D' Imagerie Guilloz, Nancy (France); UMR, S 947, Universite de Lorraine, IADI, Nancy (France); Meyer, Jean-Baptiste; Raymond, Ariane; Blum, Alain [CHU-Nancy, Service D' Imagerie Guilloz, Nancy (France); Baumann, Cedric [CHU-Nancy, Service d' Epidemiologie et Evaluation Cliniques, Nancy (France); Sirveaux, Francois [Service de Chirurgie Traumatologique et Orthopedique, Nancy (France); Coudane, Henry [CHU-Nancy, Service de Chirurgie Traumatologique et Arthroscopique de l' Appareil Locomoteur (ATOL), Nancy (France)

    2014-09-15

    To compare the image quality of CT with iterative reconstruction alone and in association with projection-based single-energy metal artifact reduction (SEMAR) for the visualization of specific periarticular soft tissue structures in patients with hip prostheses. CT studies from 48 consecutive patients with a hip prosthesis (24 unilateral and 24 bilateral) were retrospectively reconstructed using two different methods: iterative reconstruction (IR) alone and IR associated with SEMAR. The influence of metallic artifacts on the identification of various periarticular structures was evaluated subjectively by two readers. The image quality was compared in patients with unilateral and bilateral prostheses. Visualization of periprosthetic soft tissue was significantly improved by the SEMAR algorithm (p < 0.0001). When SEMAR was associated with IR, the gluteus minimus and medius tendons, obturator internus muscle, prostate/uterus and bladder could be seen with medium or high confidence. There were no significant differences in image quality between patients with unilateral or bilateral prosthesis when SEMAR was used (p > 0.2). This algorithm increased the detection of periarticular masses by 30 %. SEMAR significantly improves the image quality of periarticular soft-tissue structures in patients with hip prostheses. (orig.)

  16. Results of uncemented distal locked prosthesis in revision hip arthroplasty with proximal femoral bone loss: A retrospective study

    Directory of Open Access Journals (Sweden)

    Sanjay Agarwala

    2013-01-01

    Conclusion: Uncemented distal locked prosthesis provide adequate stability in revision THA, aiding the reconstruction of bony deficiencies while avoiding the disadvantages of fully porous or cemented implants.

  17. Hip arthroplasty with the thrust plate prosthesis in patients of 65 years of age or older: 67 patients followed 2-7 years.

    Science.gov (United States)

    Karatosun, Vasfi; Unver, Bayram; Gunal, Izge

    2008-04-01

    Thrust plate prosthesis (TPP) is a relatively new concept in total hip arthroplasty and advocated to be used in young patients. We retrospectively evaluated the results of 67 patients (71 hips) who were older than 65 years of age and underwent hip arthroplasty using the TPP. There were 50 female and 17 male patients with a mean age 71 (range 65-89) years. All patients received accelerated rehabilitation program either with full weight bearing in the second postoperative day or at 6 weeks. All patients were followed-up for at least 2 years (range 28-87 months). The average Harris hip score improved from 43 (range 8-72) to 93 (range 64-100) at the latest follow-up (p hip score of patients with full weight bearing in the second postoperative day or 6 weeks (p = 0.57). We conclude that the TPP could be indicated for older patients without age limit and that an accelerated rehabilitation program with early weight bearing can be applied to these patients.

  18. Functional outcome, revision rates and mortality after primary total hip replacement--a national comparison of nine prosthesis brands in England.

    Science.gov (United States)

    Pennington, Mark; Grieve, Richard; Black, Nick; van der Meulen, Jan H

    2013-01-01

    The number of prosthesis brands used for hip replacement has increased rapidly, but there is little evidence on their effectiveness. We compared patient-reported outcomes, revision rates, and mortality for the three most frequently used brands within each prosthesis type: cemented (Exeter V40 Contemporary, Exeter V40 Duration and Exeter V40 Elite Plus Ogee), cementless (Corail Pinnacle, Accolade Trident, and Taperloc Exceed), and hybrid (Exeter V40 Trilogy, Exeter V40 Trilogy, and CPT Trilogy). We used three national databases of patients who had hip replacements between 2008 and 2011 in the English NHS to compare functional outcome (Oxford Hip Score (OHS) ranging from 0 (worst) to 48 (best)) in 43,524 patients at six months. We analysed revisions and mortality in 187,201 patients. We used multiple regression to adjust for pre-operative differences. Prosthesis type had an impact on post-operative OHS and revision rates (both pprosthesis type were small and not significant (p = 0.06). Functional outcome varied according to brand among cemented (p = 0.05, with Exeter V40 Duration having the best) and cementless prostheses (p = 0.01, with Corail Pinnacle having the best). Revision rates varied according to brand among hybrids (p = 0.05, with Exeter V40 Trident having the lowest). Functional outcomes were better with cementless cups and revision rates were lower with cemented stems, which underlies the good overall performance of hybrids. The hybrid Exeter V40 Trident seemed to produce the best overall results. This brand should be considered as a benchmark in randomised trials.

  19. Information for Patients Who Have Metal-on-Metal Hip Implants

    Science.gov (United States)

    ... cause a reaction around the joint, leading to deterioration of the tissue around the joint, loosening of ... FEAR Act Site Map Nondiscrimination Website Policies U.S. Food and Drug Administration 10903 New Hampshire Avenue Silver ...

  20. Effect of carbon ion implantation on the tribology of metal-on-metal bearings for artificial joints

    Directory of Open Access Journals (Sweden)

    Koseki H

    2017-05-01

    Full Text Available Hironobu Koseki,1 Masato Tomita,2 Akihiko Yonekura,2 Takashi Higuchi,1 Sinya Sunagawa,2 Koumei Baba,3,4 Makoto Osaki2 1Department of Locomotive Rehabilitation Science, Unit of Rehabilitation Sciences, 2Department of Orthopedic Surgery, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto, Nagasaki, Japan; 3Industrial Technology Center of Nagasaki, Ikeda, Omura, Nagasaki, Japan; 4Affiliated Division, Nagasaki University School of Engineering, Bunkyo, Nagasaki, Japan Abstract: Metal-on-metal (MoM bearings have become popular due to a major advantage over metal-on-polymer bearings for total hip arthroplasty in that the larger femoral head and hydrodynamic lubrication of the former reduce the rate of wear. However, concerns remain regarding adverse reactions to metal debris including metallosis caused by metal wear generated at the taper-head interface and another modular junction. Our group has hypothesized that carbon ion implantation (CII may improve metal wear properties. The purpose of this study was to investigate the wear properties and friction coefficients of CII surfaces with an aim to ultimately apply these surfaces to MoM bearings in artificial joints. CII was applied to cobalt-chromium-molybdenum (Co-Cr-Mo alloy substrates by plasma source ion implantation. The substrates were characterized using scanning electron microscopy and a 3D measuring laser microscope. Sliding contact tests were performed with a simple geometry pin-on-plate wear tester at a load of 2.5 N, a calculated contact pressure of 38.5 MPa (max: 57.8 MPa, a reciprocating velocity of 30 mm/s, a stroke length of 60 mm, and a reciprocating cycle count of 172,800 cycles. The surfaces of the CII substrates were generally featureless with a smooth surface topography at the same level as untreated Co-Cr-Mo alloy. Compared to the untreated Co-Cr-Mo alloy, the CII-treated bearings had lower friction coefficients, higher resistance to catastrophic damage, and

  1. The Müller self-locking cemented total hip prosthesis with polyethylene liner: After twenty years, what did they become?

    Science.gov (United States)

    Erivan, Roger; Villatte, Guillaume; Khelif, Youcef Reda; Pereira, Bruno; Galvin, Myriam; Descamps, Stéphane; Boisgard, Stéphane

    2017-01-01

    The M.E. Müller (MEM) prosthesis is a self-locking straight stem. Although this prosthesis is widely used, few outcomes have been published thus far. We examined long-term outcomes with the MEM cemented self-locking total hip arthroplasty (THA) with a polyethylene liner and 28-mm head. Between 1993 and 1994, 167 patients (173 hips) underwent primary THA implantation and were invited for clinical and radiological review a mean of 20.6 (20.1 - 21.7) years later; 111 patients had a metal and 62 a ceramic head. Hip function was assessed using the Postel Merle d'Aubigné Score. Overall, 121 patients died and six were lost to follow-up. Forty patients (41 hips) were reviewed. Five patients required revision, of whom two were due to acetabular loosening, one to premature haematoma, one to recurrent dislocation and one to femoral fracture. Wear levels were significantly lower with ceramic than metal heads. The majority of radiological or clinical failures were acetabular (7.3 % versus 2.4 % femoral). At the femoral level, osteolysis was observed in seven patients (17 %). Twenty-year survival was 88.67 ± 6.61 % using an endpoint of all-cause revision and 97.9 ± 2.1 % using femoral failure as the endpoint. Our retrospective analysis confirms the good results seen with the MEM stem in the literature and support the "French paradox" concept. Failures of these prostheses with a cemented polyethylene cup are largely on the acetabular side and, as such, the cup is the weak link. Improvements in survival will require optimisation of cup fixation and the use of a ceramic head to reduce wear in patients with a long life expectancy.

  2. Functional outcome, revision rates and mortality after primary total hip replacement--a national comparison of nine prosthesis brands in England.

    Directory of Open Access Journals (Sweden)

    Mark Pennington

    Full Text Available The number of prosthesis brands used for hip replacement has increased rapidly, but there is little evidence on their effectiveness. We compared patient-reported outcomes, revision rates, and mortality for the three most frequently used brands within each prosthesis type: cemented (Exeter V40 Contemporary, Exeter V40 Duration and Exeter V40 Elite Plus Ogee, cementless (Corail Pinnacle, Accolade Trident, and Taperloc Exceed, and hybrid (Exeter V40 Trilogy, Exeter V40 Trilogy, and CPT Trilogy.We used three national databases of patients who had hip replacements between 2008 and 2011 in the English NHS to compare functional outcome (Oxford Hip Score (OHS ranging from 0 (worst to 48 (best in 43,524 patients at six months. We analysed revisions and mortality in 187,201 patients. We used multiple regression to adjust for pre-operative differences. Prosthesis type had an impact on post-operative OHS and revision rates (both p<0.001. Patients with hybrid prostheses had the best functional outcome (mean OHS 39.4, 95%CI 39.1 to 39.7 and those with cemented prostheses the worst (37.7, 37.3 to 38.1. Patients with cemented prostheses had the lowest reported 5-year revision rates (1.3%, 1.2% to 1.4% and those with cementless prostheses the highest (2.2%, 2.1% to 2.4%. Differences in mortality according to prosthesis type were small and not significant (p = 0.06. Functional outcome varied according to brand among cemented (p = 0.05, with Exeter V40 Duration having the best and cementless prostheses (p = 0.01, with Corail Pinnacle having the best. Revision rates varied according to brand among hybrids (p = 0.05, with Exeter V40 Trident having the lowest.Functional outcomes were better with cementless cups and revision rates were lower with cemented stems, which underlies the good overall performance of hybrids. The hybrid Exeter V40 Trident seemed to produce the best overall results. This brand should be considered as a benchmark in randomised trials.

  3. 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.

  4. Detection of Pantoea agglomerans in hip prosthetic infection by sonication of the removed prosthesis: the first reported case.

    Science.gov (United States)

    Hischebeth, Gunnar T R; Kohlhof, Hendrik; Wimmer, Matthias D; Randau, Thomas M; Bekeredjian-Ding, Isabelle; Gravius, Sascha

    2013-01-01

    Pantoea agglomerans is a rare isolate in orthopaedic patients. We describe the first case of an acute hip prosthetic joint infection (PJI) caused by Pantoea agglomerans. The microorganism was detected after sonication of the removed hip endoprosthesis.

  5. Assessment of pain-related fear in patients with the thrust plate prosthesis (TPP): due to hip fracture and hip osteoarthritis.

    Science.gov (United States)

    Sengul, Yesim Salik; Unver, Bayram; Karatosun, Vasfi; Gunal, Izge

    2011-01-01

    The aim of this study is to determine the differences between hip fracture and hip arthrosis groups and to assess pain related fear of injury in patients who were operated using the TPP following hip fracture or hip arthrosis. Fifty-eight patients (mean age = 63.9 ± 10.3 years) who were operated using the TPP, following hip fracture (hip fracture group; n = 25) or coxarthrosis (coxarthrosis group; n = 33) were recruited. All of the measurements were performed after a follow-up time of at least 2 years. Functional level by Harris Hip Scoring System (HHS), pain related fear by Tampa Scale for Kinesiophobia (TSK) and pain intensity by numerical rating scale (NRS) was evaluated. There were no significant differences between demographic and clinical characteristics of two groups. However, pain intensity was higher in coxarthrosis group than hip fracture group. There was no correlation between the TSK scores and either Harris scores or NRS scores (p > 0.05) in the hip fracture group. No correlation between NRS and TSK was found in coxarthrosis group but there was a significant correlation between TSK and HHS. TSK scores were high in both groups. High TSK scores proved us that the patients with TPP had fear of movement even they had enough physical performance. The coxarthrosis group had higher pain intensity. Rehabilitation clinicians should consider pain-related belief which is more important than pain intensity and functional level in coxarthrosis patients. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  6. Total hip prosthesis complication, periprosthetic infection with external fistulizing due to Enterobacter cloacae complex multiple drugs resistance: A clinical case report.

    Science.gov (United States)

    Amorese, V; Corda, M; Donadu, M; Usai, D; Pisanu, F; Milia, F; Marras, F; Sanna, A; Delogu, D; Mazzarello, V; Manzoni, G; Conti, M; Meloni, G B; Zanetti, S; Doria, C

    2017-01-01

    The Enterobacter cloacae is a microorganism found in the intestinal flora of the majority of animals, including humans. Primary infections caused by E. cloacae are rare in immunocompetent patients, but are very common in hospital settings in newborns and immunocompromised patients, and can be aggravated by the insurgence of antibiotic resistance. The incidence of periprosthetic hip infections is just below 2%. A 76year old woman with multiple comorbidities underwent surgical implantation of intermediary total hip prosthesis of the left hip, in a different health facility, in February 2014, after the basicervical fracture of the upper femur extremity due to trauma. After an episode of dislocation of the prosthetic implant, in September 2014, she underwent a surgical operation to implant the acetabular component. A month later not in our facility, following a re-hospitalization for the dislocation of the arthroprosthesis, an infection from E. cloacae complex was discovered. After 2 years of chronic infection she came to our attention; the clinical picture featured coxalgia and secreting fistula in the surgical wound. Following a specific antibiotic therapy, carried out intravenously over the course of a month, we decided to intervene removing the left hip arthroprosthesis and placing an antibiotic spacer following the direction deduced from the antibiogram study of August 2016. The patient was hospitalized in our facility and 2 months later she underwent another operation to remove the antibiotic spacer and to place a new total hip arthroprosthesis. Multiple swabs showed the complete healing from the infection, which was confirmed a couple of months later. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. [Is there a bone-preserving bone remodelling in short-stem prosthesis? DEXA analysis with the Nanos total hip arthroplasty].

    Science.gov (United States)

    Götze, C; Ehrenbrink, J; Ehrenbrink, H

    2010-08-01

    It has been suggested that the use of a short-stem prosthesis could conserve proximal bone by proximal load transfer. Proximal stress shielding should be reduced, a phenomenon that has been associated with bone resorption around traditional stems. Bone remodelling of a metaphyseal fixed stem (Nanos, Smith & Nephew Int.) was analysed by the dual-energy x-ray absorptiometry. This study included 36 patients undergoing the total hip replacement using the Nanos short stem in comparison to 36 patients operated by a traditional long-stemmed femoral stem (Alloclassic). In all cases a threaded cup was inserted. Both groups were not different in regard to the BMI or in regard to the quality of bone (BMI). The average age of the group of patients with the short-stem prosthesis was slightly younger (average 54.2 years [range: 29 to 75]) than the patient group with the long-stem prosthesis (average 61.1 years [range: 39 to 71]). A prospective clinical analysis was done by the Harris hip score (HHS) and the Sutherland score to evaluate the social quality of life. With a minimum follow-up of 12 months in all cases, radiological changes in regard to stem subsidence, periprosthetic osteolysis or linear radiolucencies were analysed. The changes of periprosthetic bone density were examined with DEXA in all patients 3 and 12 months postoperatively. No patients required reoperation because of loosening or subsidence of the short-stem prosthesis. The HHS improved from a mean of 43.1 (range: 9 to 51) to 96.5 points (range: 79 to 100) in the short-stem group and to 91.3 points (range: 61 to 100) in the group of patients with long-stemmed femoral component. Radiographic follow-up revealed no evidence of component loosening or migration of the short-stem. Along the greater trochanter an osteolysis of the bone structure was found in two cases. A decrease of the proximal periprosthetic bone density (Gruen zone I, -6.4%) and in zone VII (-7.2%) were measured. An increase of the BMD in the

  8. A Randomized Seven-Year Study on Performance of the Stemmed Metal M2a-Magnum and Ceramic C2a-Taper, and the Resurfacing ReCap Hip Implants.

    Science.gov (United States)

    Borgwardt, Arne; Borgwardt, Lotte; Zerahn, Bo; Daugaard, Henrik; Borgwardt, Lise; Ribel-Madsen, Søren

    2017-12-05

    The large-diameter metal-on-metal hip prostheses were expected to have low wear and reduced dislocation rate compared to the traditional metal-on-polyethylene implants. We compare 2 such prostheses, the ReCap resurfacing implant and the M2a-Magnum stemmed implant, with the C2a ceramic-on-ceramic stemmed implant as to clinical performance, serum concentrations of prosthesis metals, and the durability of the implants in a randomized, controlled clinical trial at 7 years of follow-up. All included patients had osteoarthritis. Preoperatively, the size of the implants was estimated from a magnetic resonance imaging (MRI) scan. Follow-up data included serum cobalt and chromium concentrations, Oxford and Harris Hip Scores, leg press and abduction force, 6-minute walk distance, WOMAC and SF-36 self-assessment scores, and from the 7th postoperative year also ultrasonography (US) examination of the soft tissue adjacent to the implant as well as MRI with metal artifact reduction sequence (MARS-MRI) when indicated. One hundred fifty-two hips in 146 patients were included. The serum cobalt and chromium concentrations were significantly higher for the 2 metal-on-metal prostheses than for the ceramic-on-ceramic, with the M2a-Magnum as the highest. No significant difference was found between the groups concerning physical performance measurements and scores as well as dislocations and prosthesis survival. Five revisions were done and concerned all groups, for reasons of pain, high serum cobalt and chromium concentrations, cystic fluid collection around the joint, and infection. Metal concentrations, US, and MARS-MRI contributed to the decision making regarding prosthesis revision. Metal concentrations were significantly higher for the metal-on-metal prostheses than for the ceramic-on-ceramic. The clinical performance was good in all 3 prosthesis groups. Metal concentrations, US, and MARS-MRI findings were of use to identify hips needing revision. ID Number in Clinical

  9. [History of hip arthroplasty].

    Science.gov (United States)

    Płomiński, Janusz; Kwiatkowski, Krzysztof

    2007-02-01

    The authors present the history of hip prosthesis in treatment of coxarthrosis. Despite eighty years of experience the problem of gaining good and long-term results still exist and is difficult to solve. Even changing the way on cementless stabilization of prosthesis doesn't has result in solving the problem of aseptic loosening of hip arthroplasty. Problems of wear derbies made the producers find new to reduce particulate debris. The future of hip arthroplasty is connected with hip resurfacing. Moreover, the higher number of primary hip plasty the more prosthesis are loosening. The treatment is far more difficult and more expensive.

  10. Tribology of total hip arthroplasty prostheses: What an orthopaedic surgeon should know.

    Science.gov (United States)

    Rieker, Claude B

    2016-02-01

    Articulating components should minimise the generation of wear particles in order to optimize long-term survival of the prosthesis.A good understanding of tribological properties helps the orthopaedic surgeon to choose the most suitable bearing for each individual patient.Conventional and highly cross-linked polyethylene articulating either with metal or ceramic, ceramic-on-ceramic and metal-on-metal are the most commonly used bearing combinations.All combinations of bearing surface have their advantages and disadvantages. An appraisal of the individual patient's objectives should be part of the assessment of the best bearing surface. Cite this article: Rieker CB. Tribology of total hip arthroplasty prostheses: what an orthopaedic surgeon should know. EFORT Open Rev 2016;1:52-57. DOI: 10.1302/2058-5241.1.000004.

  11. Simulated studies of wear and friction in total hip prosthesis components with various ball sizes and surface finishes

    Science.gov (United States)

    Swikert, M. A.; Johnson, R. L.

    1976-01-01

    Experiments were conducted on a newly designed total hip joint simulator. The apparatus closely simulates the complex motions and loads of the human hip in normal walking. The wear and friction of presently used appliance configurations and materials were determined. A surface treatment of the metal femoral ball specimens was applied to influence wear. The results of the investigation indicate that wear can be reduced by mechanical treatment of metal femoral ball surfaces. A metallographic examination and surface roughness measurements were made.

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

    Directory of Open Access Journals (Sweden)

    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. Expectations and outcome of a scientifically developed hip prosthesis in 170 hips with a follow-up of 5-12 years

    NARCIS (Netherlands)

    van de Groes, Sebastiaan; Ypma, Jan; Spierings, Pieter; Verdonschot, Nicolaas Jacobus Joseph

    2012-01-01

    Roentgen stereophotogrammetric analysis (RSA) is commonly used to assess prosthetic stability as a predictor of the long term clinical outcome of new total hip systems. Although the RSA technique is very accurate, it may not be trivial to interpret migration rates into clinical outcome, as critical

  14. [Virtual simulation for optimizing the range of motion in hip alloarthroplasty using an adapted thrust-plate prosthesis model].

    Science.gov (United States)

    Jerosch, J; Wetzel, R; Aldinger, G; Weipert, A; Hanusek, S; Filler, T J; Peuker, E T

    2000-07-01

    The purpose of the present study was to increase the free range of motion in conventional trust-plate prosthesis design and to optimize the trust-plate contact as well as the osteointegration area below the trust-plate. For the first part of the study, the two-dimensional geometry of the osteotomy plane was demonstrated in 25 CT-reconstructed femora after performing a virtual cut at a CCD angle of 135 degrees. In the second part, we constructed a prototype of an anatomic adapted trust-plate prosthesis (A-TPP) with an optimized trust-plate and corpus geometry based on the three-dimensional data of three human cadaveric femurs (age 67-75 years). In the final step, we documented the range of motion with computer-aided movement-mapping and compared the conventional TPP with the A-TPP. The results showed a wide variance in osteotomy geometry in the 12 femurs. With the A-TPP, we were able to obtain a much better fit in the trust plate surface. The movement-mapping showed a much higher range of motion in the A-TPP implant. With the A-TPP, the implant surface area for osteointegration could also be significantly increased.

  15. Study of three-dimensional morphology of the proximal femur in developmental adult dysplasia of the hip suggests that the on-shelf modular prosthesis may not be an ideal choice for patients with Crowe type IV hips.

    Science.gov (United States)

    Liu, Shuanglu; Zuo, Jianlin; Li, Zhizhou; Yang, Yuhui; Liu, Tong; Xiao, Jianlin; Gao, Zhongli

    2017-04-01

    trochanter. The on-shelf modular prosthesis may not be an ideal choice for the Chinese patients with Crowe IV hips.

  16. Is the bone-bonding ability of a cementless total hip prosthesis enhanced by alkaline and heat treatments?

    Science.gov (United States)

    So, Kazutaka; Kaneuji, Ayumi; Matsumoto, Tadami; Matsuda, Shuichi; Akiyama, Haruhiko

    2013-12-01

    Cementless total hip arthroplasty (THA) implants using alkaline and heat treatments were developed to enhance bone bonding. Although bone-bonding ability of the alkali- and heat-treated titanium surface has been demonstrated in animal studies, it remains unknown whether it enhances or provides durable bone bonding in humans. We therefore (1) determined long-term survivorship, function, and radiographic signs of failure of fixation of alkali- and heat-treated THA implants; and (2) histologically examined their bone-bonding ability in two human retrievals. We retrospectively reviewed 58 patients who underwent 70 primary THAs, of whom 67 were available for minimum followup of 8 years (average, 10 years; range, 8-12 years). Survival rate was calculated. Hip function was evaluated using the Japan Orthopaedic Association (JOA) hip scores, and radiographic signs of implant failure were determined from anteroposterior radiographs. Two retrieved implants were investigated histologically. Using revision for any reason as the end point, the overall survival rate was 98% (95% confidence interval, 96%-100%) at 10 years. The patients' average JOA hip scores improved from 47 points preoperatively to 91 points at the time of the last followup. No implant had radiographic signs of loosening. Histologically we observed bone in the pores 2 weeks after implantation in one specimen and apparently direct bonding between bone and the titanium surface in its deep pores 8 years after implantation. Cementless THA implants with alkaline and heat treatments showed a high survival rate. Further study is required to determine whether the treatment enhances direct bone bonding.

  17. Measurements of hip-bone distortions caused by the stress of inserted prosthesis by means of the speckle photography method

    Science.gov (United States)

    Gajda, Jerzy K.; Niesterowicz, Andrzej; Mazurkiewicz, Henryk

    1995-03-01

    A high number of osseous diseases, particularly of the backbone and hip-joint regions, result in a need for their overall treatment and prevention. Two basic treatment methods are used: physical exercises at an early stage of the illness, and surgical treatment in an advanced stage. Recently, in operational treatment of coxarthrosis the elements of the joint (acetabulum and capitellum) were replaced by their artificial counterparts, despite some drawbacks and unknowns related to this kind of treatment. In order to check the effectiveness of this treatment and to eliminate its drawbacks we have tested the joint by means of speckle photography method. The objective of this paper is an attempt to evaluate stress and displacement distributions in a system consisting of artificial acetabulum and capitellum and a natural bone in order to determine an optimum fitting of artificial acetabulum and capitellum and a natural bone in order to determine an optimum fitting of artificial elements that guarantees uniform distribution of stresses corresponding to anatomical and physiological parameters of the hip-joint. Speckle photographs have been analyzed point by point with the help of the algorithm for striped images processing.

  18. Micromotions at the taper interface between stem and neck adapter of a bimodular hip prosthesis during activities of daily living.

    Science.gov (United States)

    Jauch, Sabrina Yvonne; Huber, Gerd; Sellenschloh, Kay; Haschke, Henning; Baxmann, Marc; Grupp, Thomas M; Morlock, Michael M

    2013-08-01

    The stem-neck taper interface of bimodular hip endoprostheses bears the risk of micromotions that can result in ongoing corrosion due to removal of the passive layer and ultimately cause implant fracture. We investigated the extent of micromotions at the stem-neck interface and the seating behavior of necks of one design made from different alloys during daily activities. Modular hip prostheses (n = 36, Metha®, Aesculap AG, Germany) with neck adapters (CoCr29Mo6 or Ti6Al4V) were embedded in PMMA (ISO 7206-4) and exposed to cyclic loading with peak loads ranging from walking (Fmax  = 2.3 kN) to stumbling (Fmax  = 5.3 kN). Translational and rotational micromotions at the taper interface and seating characteristics during assembly and loading were determined using four eddy-current sensors. Seating during loading after implant assembly was dependent on load magnitude but not on material coupling. Micromotions in the stem-neck interface correlated positively with load levels (CoCr: 2.6-6.3 µm, Ti: 4.6-13.8 µm; p < 0.001) with Ti neck adapters exhibiting significantly larger micromotions than CoCr (p < 0.001). These findings explain why high body weights and activities related to higher loads could increase the risk of fretting-induced implant failures in clinical application, especially for Ti-Ti combinations. Still, the role of taper seating is not clearly understood. Copyright © 2013 Orthopaedic Research Society.

  19. Tribology of total hip arthroplasty prostheses

    OpenAIRE

    Rieker, Claude B.

    2016-01-01

    Articulating components should minimise the generation of wear particles in order to optimize long-term survival of the prosthesis. A good understanding of tribological properties helps the orthopaedic surgeon to choose the most suitable bearing for each individual patient. Conventional and highly cross-linked polyethylene articulating either with metal or ceramic, ceramic-on-ceramic and metal-on-metal are the most commonly used bearing combinations. All combinations of bearing surface have t...

  20. Large diameter metal on metal total hip replacement for femoral neck fractures with neurological conditions A retrospective assessment

    Directory of Open Access Journals (Sweden)

    Jia Li

    2014-01-01

    Conclusion: We believe the use of L-MoM can diminish the rate of instability or dislocation, after operation. The L-MoM is an option for patients with Parkinson′s disease and poliomyelitis with femoral neck fracture.

  1. Review of cobalt toxicokinetics following oral dosing: Implications for health risk assessments and metal-on-metal hip implant patients.

    Science.gov (United States)

    Tvermoes, Brooke E; Paustenbach, Dennis J; Kerger, Brent D; Finley, Brent L; Unice, Kenneth M

    2015-05-01

    Cobalt (Co) can stimulate erythropoietin production in individuals at doses exceeding 25 mg CoCl2/day. Co has also been shown to exert effects on the thyroid gland, heart and nervous system at sufficient doses. The biological activity of Co is dictated by the concentration of free (unbound) ionic Co(2+). Blood concentrations, as well as, urinary excretion rates of Co are reliable biomarkers for systemic Co exposure. A recent series of human volunteer Co-supplement studies simultaneously measured Co blood and urine concentrations, as well as, Co speciation in serum, and a number of biochemical and clinical parameters. It was found in these studies that peak Co whole blood concentration as high as 117 μg/L were not associated with changes in hematological parameters such as increased red blood cell (RBC) count, hemoglobin (Hgb) or hematocrit (Hct) levels, nor with changes in cardiac, neurological or, thyroid function. Using a Co biokinetic model, the estimated Co systemic tissue concentrations (e.g., liver, kidney, and heart) following 90-days of Co-dietary supplementation with ∼1 mg Co/day were found to be similar to estimated tissue concentrations in implant patients after 10 years of exposure at continuous steady state Co blood concentration of ∼10 μg/L. This study is the first to present modeled Co tissue concentrations at various doses following sub-chronic and chronic exposure. The modeled steady state tissue Co concentrations in combination with the data on adverse health effects in humans should help in the characterization of potential hazards associated with increased blood Co concentrations due to exposure to dietary supplements or cobalt-chromium (Co-Cr) containing implants.

  2. The Interchangeability of Plasma and Whole Blood Metal Ion Measurement in the Monitoring of Metal on Metal Hips

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    Ibrahim A. Malek

    2015-01-01

    Full Text Available One hundred and twenty six paired samples of plasma and whole blood were measured with inductively coupled plasma mass spectrometry technique for metal ions analysis to determine a relationship between them. There was a significant difference between the mean plasma and whole blood concentrations of both cobalt (Co and chromium (Cr (p<0.0001 for both Co and Cr. The mean ratio between plasma and whole blood Cr and Co was 1.56 (range: 0.39–3.85 and 1.54 (range: 0.64–18.26, respectively, but Bland and Altman analysis illustrated that this relationship was not universal throughout the range of concentrations. There was higher variability at high concentrations for both ions. We conclude that both these concentrations should not be used interchangeably and conversion factors are unreliable due to concentration dependent variability.

  3. The Interchangeability of Plasma and Whole Blood Metal Ion Measurement in the Monitoring of Metal on Metal Hips

    OpenAIRE

    Malek, Ibrahim A.; Rogers, Joanne; King, Amanda Christina; Clutton, Juliet; Winson, Daniel; John, Alun

    2015-01-01

    One hundred and twenty six paired samples of plasma and whole blood were measured with inductively coupled plasma mass spectrometry technique for metal ions analysis to determine a relationship between them. There was a significant difference between the mean plasma and whole blood concentrations of both cobalt (Co) and chromium (Cr) (p < 0.0001 for both Co and Cr). The mean ratio between plasma and whole blood Cr and Co was 1.56 (range: 0.39?3.85) and 1.54 (range: 0.64?18.26), respectively, ...

  4. Fatal cobalt toxicity after total hip arthroplasty revision for fractured ceramic components.

    Science.gov (United States)

    Fox, Kimberly A; Phillips, Todd M; Yanta, Joseph H; Abesamis, Michael G

    2016-11-01

    Post-arthroplasty metallosis, which refers to metallic corrosion and deposition of metallic debris in the periprosthetic soft tissues of the body, is an uncommon complication. Systemic cobalt toxicity post-arthroplasty is extremely rare. The few known fatal cases of cobalt toxicity appear to be a result of replacing shattered ceramic heads with metal-on-metal or metal-on-polyethylene implants. Friction between residual shards of ceramic and cobalt-chromium implants allows release of cobalt into the synovial fluid and bloodstream, resulting in elevated whole blood cobalt levels and potential toxicity. This is a single patient chart review of a 60-year-old woman with prior ceramic-on-ceramic right total hip arthroplasty complicated by fractured ceramic components and metallosis of the joint. She underwent synovectomy and revision to a metal-on-polyethylene articulation. Ten months post-revision, she presented to the emergency department (ED) with right hip pain, dyspnea, worsening hearing loss, metallic dysgeusia, and weight loss. Chest CTA revealed bilateral pulmonary emboli (PE), and echocardiogram revealed new cardiomyopathy with global left ventricular hypokinesis with an ejection fraction (EF) of 35-40% inconsistent with heart strain from PE. Whole blood cobalt level obtained two days into her admission was 424.3 mcg/L and 24-h urine cobalt level was 4830.5 mcg/L. Although the patient initially clinically improved with regard to her PE and was discharged to home on hospital day 5, she returned 10 days later with a right hip dislocation and underwent closed reduction of the hip. The patient subsequently decompensated, developing cardiogenic shock, and respiratory failure. She went into pulseless electrical activity (PEA) and expired. Autopsy revealed an extensive metallic effusion surrounding the right hip prosthesis that tested positive for cobalt (41,000 mcg/L). There was also cobalt in the heart muscle tissue (2.5 mcg/g). A whole blood cobalt level

  5. Artroplastia total coxofemoral em cães: Estudo experimental com prótese nacional Total hip arthroplasty in dogs: Experimental study using a prosthesis made in Brazil

    Directory of Open Access Journals (Sweden)

    Bruno Watanabe Minto

    2008-02-01

    Full Text Available A prótese total da articulação coxofemoral representa uma das técnicas mais aceitas, nos Estados Unidos e na Europa, para o tratamento cirúrgico da displasia coxofemoral severa em cães. Entretanto, ainda é pouco difundida e estudada no Brasil. No presente trabalho, foi utilizada prótese confeccionada no Brasil, com o objetivo de avaliar a sua aplicação, evolução pós-operatória e complicações associadas. Foram utilizados dez cães, sadios e adultos. Todos foram submetidos ao procedimento de prótese total cimentada da articulação esquerda utilizando-se um componente femoral de cromo-cobalto, cabeça fixa, e uma cúpula acetabular de polietileno de alta densidade. As avaliações clínicas e radiográficas foram realizadas no pré-operatório e aos 30, 60, 90, 120 e 150 dias após a intervenção cirúrgica. A prótese total utilizada proporcionou um bom resultado funcional ao membro operado, em 80% dos animais. As principais complicações relacionadas foram a luxação protética e a soltura do componente acetabular.Total hip prosthesis is one of the most accepted methods used in the United States and Europe for the treatment of severe hip dysplasia in dogs. However, there are few studies with the technique and the procedure is still not well established in Brazil. A prosthesis made in Brazil was used. The purpose of this study was to evaluate its application and determine the postoperative finds and complications. Ten mature healthy dogs were used. A fixed-head cemented total hip prosthesis was applied on the left leg of the dogs. A chrome-cobalt femoral stem and high density polyetylene acetabular cup was used. Clinical and radiographic evaluations were performed before surgery and again at 30, 60, 90, 120 e 150 days post operation. Proper weight bearing was noticed on the operated limb in the majority of the dogs. The main complications were the dislocation and loosening of the acetabular cup.

  6. Metal release and metal allergy after total hip replacement with resurfacing versus conventional hybrid prosthesis 5-year follow-up of 52 patients

    DEFF Research Database (Denmark)

    Gustafson, Klas; Jakobsen, Stig S; Lorenzen, Nina D

    2014-01-01

    to an increased incidence of metal allergy. METHODS: 52 hips in 52 patients (median age 60 (51-64) years, 30 women) were randomized to either a MOM hip resurfacing system (ReCap) or a standard MOP total hip arthoplasty (Mallory Head/Exeter). Spot urine samples were collected preoperatively, postoperatively, after....... RESULTS: A statistically significant 10- to 20-fold increase in urinary levels of cobalt and chromium was observed throughout the entire follow-up in the MOM group. The prevalence of metal allergy was similar between groups. INTERPRETATION: While we observed significantly increased levels of metal ions...

  7. Total hip prosthesis complication, periprosthetic infection with external fistulizing due to Enterobacter cloacae complex multiple drugs resistance: A clinical case report

    Directory of Open Access Journals (Sweden)

    V. Amorese

    2017-01-01

    Conclusion: The patient was hospitalized in our facility and 2 months later she underwent another operation to remove the antibiotic spacer and to place a new total hip arthroprosthesis. Multiple swabs showed the complete healing from the infection, which was confirmed a couple of months later.

  8. SU-G-IeP2-03: Comparison of Dose Calculation On MAR (metal Artifact Reduction) and Non-MAR Datasets for Pelvic Patients with Hip Prosthesis and Head and Neck Patients with Dental Filling

    Energy Technology Data Exchange (ETDEWEB)

    Huang, V; Kohli, K [BC Cancer Agency, Surrey, BC (United Kingdom)

    2016-06-15

    Purpose: Metal artifact reduction (MAR) software in computed tomography (CT) was previously evaluated with phantoms demonstrating the algorithm is capable of reducing metal artifacts without affecting the overall image quality. The goal of this study is to determine the dosimetric impact when calculating with CT datasets reconstructed with and without MAR software. Methods: Twelve head and neck cancer patients with dental fillings and four pelvic cancer patients with hip prosthesis were scanned with a GE Optima RT 580 CT scanner. Images were reconstructed with and without the MAR software. 6MV IMRT and VMAT plans were calculated with AAA on the MAR dataset until all constraints met our clinic’s guidelines. Contours from the MAR dataset were copied to the non-MAR dataset. Next, dose calculation on the non-MAR dataset was performed using the same field arrangements and fluence as the MAR plan. Conformality index, D99% and V100% to PTV were compared between MAR and non-MAR plans. Results: Differences between MAR and non-MAR plans were evaluated. For head and neck plans, the largest variations in conformality index, D99% and V100% were −3.8%, −0.9% and −2.1% respectively whereas for pelvic plans, the biggest discrepancies were −32.7%, −0.4% and -33.5% respectively. The dosimetric impact from hip prosthesis is greater because it produces more artifacts compared to dental fillings. Coverage to PTV can increase or decrease depending on the artifacts since dark streaks reduce the HU whereas bright streaks increase the HU. In the majority of the cases, PTV dose in the non-MAR plans is higher than MAR plans. Conclusion: With the presence of metals, MAR algorithm can allow more accurate delineation of targets and OARs. Dose difference between MAR and non-MAR plans depends on the proximity of the organ to the high density material, the streaking artifacts and the beam arrangements of the plan.

  9. SU-G-IeP2-03: Comparison of Dose Calculation On MAR (metal Artifact Reduction) and Non-MAR Datasets for Pelvic Patients with Hip Prosthesis and Head and Neck Patients with Dental Filling

    International Nuclear Information System (INIS)

    Huang, V; Kohli, K

    2016-01-01

    Purpose: Metal artifact reduction (MAR) software in computed tomography (CT) was previously evaluated with phantoms demonstrating the algorithm is capable of reducing metal artifacts without affecting the overall image quality. The goal of this study is to determine the dosimetric impact when calculating with CT datasets reconstructed with and without MAR software. Methods: Twelve head and neck cancer patients with dental fillings and four pelvic cancer patients with hip prosthesis were scanned with a GE Optima RT 580 CT scanner. Images were reconstructed with and without the MAR software. 6MV IMRT and VMAT plans were calculated with AAA on the MAR dataset until all constraints met our clinic’s guidelines. Contours from the MAR dataset were copied to the non-MAR dataset. Next, dose calculation on the non-MAR dataset was performed using the same field arrangements and fluence as the MAR plan. Conformality index, D99% and V100% to PTV were compared between MAR and non-MAR plans. Results: Differences between MAR and non-MAR plans were evaluated. For head and neck plans, the largest variations in conformality index, D99% and V100% were −3.8%, −0.9% and −2.1% respectively whereas for pelvic plans, the biggest discrepancies were −32.7%, −0.4% and -33.5% respectively. The dosimetric impact from hip prosthesis is greater because it produces more artifacts compared to dental fillings. Coverage to PTV can increase or decrease depending on the artifacts since dark streaks reduce the HU whereas bright streaks increase the HU. In the majority of the cases, PTV dose in the non-MAR plans is higher than MAR plans. Conclusion: With the presence of metals, MAR algorithm can allow more accurate delineation of targets and OARs. Dose difference between MAR and non-MAR plans depends on the proximity of the organ to the high density material, the streaking artifacts and the beam arrangements of the plan.

  10. Treatment of femoral neck fracture by Moore Prosthesis in Cotonou ...

    African Journals Online (AJOL)

    Treatment of femoral neck fracture by Moore Prosthesis in Cotonou. AHM Akue, M Lawson, S Madougou, R Zannou, J Padonou. Abstract. Keywords: Benin; hip; Moore prosthesis; results. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  11. A simple surrogate test method to rank the wear performance of prospective ceramic materials under hip prosthesis edge-loading conditions.

    Science.gov (United States)

    Sanders, Anthony P; Brannon, Rebecca M

    2014-02-01

    This research has developed a novel test method for evaluating the wear resistance of ceramic materials under severe contact stresses simulating edge loading in prosthetic hip bearings. Simply shaped test specimens - a cylinder and a spheroid - were designed as surrogates for an edge-loaded, head/liner implant pair. Equivalency of the simpler specimens was assured in the sense that their theoretical contact dimensions and pressures were identical, according to Hertzian contact theory, to those of the head/liner pair. The surrogates were fabricated in three ceramic materials: Al2 O3 , zirconia-toughened alumina (ZTA), and ZrO2 . They were mated in three different material pairs and reciprocated under a 200 N normal contact force for 1000-2000 cycles, which created small (material pairs were ranked by their wear resistance, quantified by the volume of abraded material measured using an interferometer. Similar tests were performed on edge-loaded hip implants in the same material pairs. The surrogates replicated the wear rankings of their full-scale implant counterparts and mimicked their friction force trends. The results show that a proxy test using simple test specimens can validly rank the wear performance of ceramic materials under severe, edge-loading contact stresses, while replicating the beginning stage of edge-loading wear. This simple wear test is therefore potentially useful for screening and ranking new, prospective materials early in their development, to produce optimized candidates for more complicated full-scale hip simulator wear tests. Copyright © 2013 Wiley Periodicals, Inc.

  12. Evaluation of sorption capacity of antibiotics and antibacterial properties of a cyclodextrin-polymer functionalized hydroxyapatite-coated titanium hip prosthesis.

    Science.gov (United States)

    Taha, Mariam; Chai, Feng; Blanchemain, Nicolas; Neut, Christel; Goube, Michel; Maton, Mickael; Martel, Bernard; Hildebrand, Hartmut F

    2014-12-30

    Infection still present as one of common complications after total hip replacement (∼2.5%), which may cause serious outcomes. For preventing such risk, loading antibiotics onto implants for increasing local drug concentration at targeted sites could be a solution. This study aims at modifying the surface of hydroxyapatite (HA) coated titanium hip implant material (Ti-HA) with polymer of cyclodextrin (polyCD) for loading antibiotics, to achieve a sustained local drug delivery. Two widely applied antibiotics (tobramycin and rifampicin) in orthopedic surgery were loaded alone or in combination. The drug adsorption isotherm, drug release kinetics and drug's efficacy were thoroughly investigated. The results proved that polyCD coating significantly improved the affinity of both drugs to Ti-HA surface, while the mechanism of drug-polyCD interaction varies from the nature of drug, courtesy of the structural complex of polyCD. The advantage of dual-drug loading was highlighted by its strong efficacy against both Staphylococcus aureus and Enterobacter cloacae, which overcomes the limitation of mono-drug loading for an effective treatment against both bacterial strains. The prolonged antibacterial activity of antibiotic loaded Ti-HA-polyCD samples confirmed that polyCD could be a promising drug-delivery system, for sustained antibiotics release or other potential applications e.g., antimitotic agent release. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Finite Element Simulations of Hard-On-Soft Hip Joint Prosthesis Accounting for Dynamic Loads Calculated from a Musculoskeletal Model during Walking.

    Science.gov (United States)

    Ruggiero, Alessandro; Merola, Massimiliano; Affatato, Saverio

    2018-04-09

    The hip joint replacement is one of the most successful orthopedic surgical procedures although it involves challenges to overcome. The patient group undergoing total hip arthroplasty now includes younger and more active patients who require a broad range of motion and a longer service lifetime for the replacement joint. It is well known that wear tests have a long duration and they are very expensive, thus studying the effects of geometry, loading, or alignment perturbations may be performed by Finite Element Analysis. The aim of the study was to evaluate total deformation and stress intensity on ultra-high molecular weight polyethylene liner coupled with hard material head during one step. Moving toward in-silico wear assessment of implants, in the presented simulations we used a musculoskeletal multibody model of a human body giving the loading and relative kinematic of the investigated tribo-system during the gait. The analysis compared two frictional conditions -dry and wet and two geometrical cases- with and without radial clearance. The loads and rotations followed the variability of the gait cycle as well as stress/strain acting in the UHWMPE cup. The obtained results allowed collection of the complete stress/strain description of the polyethylene cup during the gait and calculation of the maximum contact pressure on the lateral edge of the insert. The tensional state resulted in being more influenced by the geometrical conditions in terms of radial clearance than by the variation of the friction coefficients due to lubrication phenomena.

  14. Cold forging stem of total hip prosthesis with hybrid mechanical properties; Forjamento a frio de hastes de protese total de quadril com propriedades mecanicas hibridas

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, E.S.N.; Contieri, R.J.; Cardoso, F.F.; Cremasco, A.; Button, S.T.; Caram, R., E-mail: ederlopes@fem.unicamp.b [Universidade Estadual de Campinas (FEM/UNICAMP), SP (Brazil). Fac. de Engenharia Mecanica. Dept. de Engenharia de Materiais

    2010-07-01

    Type {beta} Ti alloy is one of the most versatile groups of materials with regard to mechanical properties. Aspects such as alloying elements selection, mechanical processing and heat treatment routes empower these materials in applications where hybrid mechanical behavior is necessary. The aim of this study is to produce stems of total hip prostheses with hybrid mechanical properties using Ti-Nb alloys. Ingots were produced by using arc melting. Following, samples were subjected to specific heat treatment aiming to make cold forging. Sample characterization includes X-ray diffraction, scanning electron microscopy, Vickers hardness tests and tensile test. The experiments performed allowed to examine the effects of heat treatment parameters on the microstructure and mechanical behavior. Finally, results obtained show that the application of specific heat treatments of quenching and aging makes feasible the manufacturing of orthopedic devices with hybrid mechanical properties with regions where high mechanical strength was prioritized, while in others, low elastic modulus was the main concern. (author)

  15. Automatic assessment of volume asymmetries applied to hip abductor muscles in patients with hip arthroplasty

    Science.gov (United States)

    Klemt, Christian; Modat, Marc; Pichat, Jonas; Cardoso, M. J.; Henckel, Joahnn; Hart, Alister; Ourselin, Sebastien

    2015-03-01

    Metal-on-metal (MoM) hip arthroplasties have been utilised over the last 15 years to restore hip function for 1.5 million patients worldwide. Althoug widely used, this hip arthroplasty releases metal wear debris which lead to muscle atrophy. The degree of muscle wastage differs across patients ranging from mild to severe. The longterm outcomes for patients with MoM hip arthroplasty are reduced for increasing degrees of muscle atrophy, highlighting the need to automatically segment pathological muscles. The automated segmentation of pathological soft tissues is challenging as these lack distinct boundaries and morphologically differ across subjects. As a result, there is no method reported in the literature which has been successfully applied to automatically segment pathological muscles. We propose the first automated framework to delineate severely atrophied muscles by applying a novel automated segmentation propagation framework to patients with MoM hip arthroplasty. The proposed algorithm was used to automatically quantify muscle wastage in these patients.

  16. Antigranulocyte scintigraphy of septic loosening of hip prosthesis: influence of different analyzing methods; Antigranulozytenszintigraphie bei septischer Hueft-Endoprothesen-Lockerung: Einfluss unterschiedlicher Auswertemethoden

    Energy Technology Data Exchange (ETDEWEB)

    Klett, R.; Steiner, D.; Puille, M.; Khalisi, A.; Bauer, R. [Giessen Univ. (Germany). Klinik fuer Nuklearmedizin; Matter, H.P.; Stuerz, H. [Giessen Univ. (Germany). Orthopaedische Klinik

    2001-06-01

    Diagnosis of infection with help of antigranulocyte scintigraphy near body stem is difficult because of contemporary visualisation of bone marrow. Therefore, we investigated, whether it is possible to improve the accuracy in diagnosing septic loosening of hip endoprosthesis by changing the analyzing methods. Methods: In 28 patients, the results of a visual interpretation of late scan, a visual interpretation and a quantitative interpretation of time-activity-course were compared. These results were verified by histology respectively microbiology. Results: Histological and microbiological verification found 14 septic loosening and 14 aseptic loosening of the hip protheses. Therefore, sensitivity, specificity, negative and positive predictive value for the visual interpretation of late scan were 0.86, 0.57, 0.80 and 0.67. For visual and quantitative interpretation of time-activity-course we found 0.86, 0.79, 0.85 and 0.80 respectively 1, 0.93, 1, 0.93. For interobserver agreement we found kappa coefficients of 0.28 {+-} 0.2 for visual interpretation of late scan, 0.48 {+-} 0.17 for visual interpretation and 1.0 {+-} 0 for quantitative interpretation of time-activity-course. Conclusion: In all investigated values quantitative interpretation of time-activity-course was superior to the other analyzing methods. Therefore, antigranulocyte scintigraphy for septic loosening of hip endoprosthesis should be interpreted quantitatively. (orig.) [German] Bei der Entzuendungsdiagnostik mittels Antigranulozytenszintigraphie ergeben sich in der Naehe des Koerperstammes aufgrund der gleichzeitigen Knochenmarkdarstellung Beurteilungsschwierigkeiten, da nicht immer sicher zwischen entzuendlichen Fokus beziehungsweise Knochenmark zu unterscheiden ist. Es wurde daher untersucht, ob bei der Diagnostik der septischen Hueft-Endoprothesen-Lockerung durch Aenderung des Auswerteverfahrens eine Verbesserung der Aussage zu erzielen ist. Methode: Bei 28 Patienten wurden die Ergebnisse einer

  17. Activation of noble metals on metal-carbide surfaces: novel catalysts for CO oxidation, desulfurization and hydrogenation reactions.

    Science.gov (United States)

    Rodriguez, José A; Illas, Francesc

    2012-01-14

    This perspective article focuses on the physical and chemical properties of highly active catalysts for CO oxidation, desulfurization and hydrogenation reactions generated by depositing noble metals on metal-carbide surfaces. To rationalize structure-reactivity relationships for these novel catalysts, well-defined systems are required. High-resolution photoemission, scanning tunneling microscopy (STM) and first-principles periodic density-functional (DF) calculations have been used to study the interaction of metals of Groups 9, 10 and 11 with MC(001) (M = Ti, Zr, V, Mo) surfaces. DF calculations give adsorption energies that range from 2 eV (Cu, Ag, Au) to 6 eV (Co, Rh, Ir). STM images show that Au, Cu, Ni and Pt grow on the carbide substrates forming two-dimensional islands at very low coverage, and three-dimensional islands at medium and large coverages. In many systems, the results of DF calculations point to the preferential formation of admetal-C bonds with significant electronic perturbations in the admetal. TiC(001) and ZrC(001) transfer some electron density to the admetals facilitating bonding of the adatom with electron-acceptor molecules (CO, O(2), C(2)H(4), SO(2), thiophene, etc.). For example, the Cu/TiC(001) and Au/TiC(001) systems are able to cleave both S-O bonds of SO(2) at a temperature as low as 150 K, displaying a reactivity much larger than that of TiC(001) or extended surfaces of bulk copper and gold. At temperatures below 200 K, Au/TiC is able to dissociate O(2) and perform the 2CO + O(2)→ 2CO(2) reaction. Furthermore, in spite of the very poor hydrodesulfurization performance of TiC(001) or Au(111), a Au/TiC(001) surface displays an activity for the hydrodesulfurization of thiophene higher than that of conventional Ni/MoS(x) catalysts. In general, the Au/TiC system is more chemically active than systems generated by depositing Au nanoparticles on oxide surfaces. Thus, metal carbides are excellent supports for enhancing the chemical

  18. Fretting and Corrosion Between a Metal Shell and Metal Liner May Explain the High Rate of Failure of R3 Modular Metal-on-Metal Hips.

    Science.gov (United States)

    Ilo, Kevin C; Derby, Emma J; Whittaker, Robert K; Blunn, Gordon W; Skinner, John A; Hart, Alister J

    2017-05-01

    The R3 acetabular system used with its metal liner has higher revision rates when compared to its ceramic and polyethylene liner. In June 2012, the medical and healthcare products regulatory agency issued an alert regarding the metal liner of the R3 acetabular system. Six retrieved R3 acetabular systems with metal liners underwent detailed visual analysis using macroscopic and microscopic techniques. Visual analysis discovered corrosion on the backside of the metal liners. There was a distinct border to the areas of corrosion that conformed to antirotation tab insertions on the inner surface of the acetabular shell, which are for the polyethylene liner. Scanning electron microscopy indicated evidence of crevice corrosion, and energy-dispersive X-ray analysis confirmed corrosion debris rich in titanium. The high failure rate of the metal liner option of the R3 acetabular system may be attributed to corrosion on the backside of the liner which appear to result from geometry and design characteristics of the acetabular shell. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Feasibility of asymmetric flow field-flow fractionation coupled to ICP-MS for the characterization of wear metal particles and metalloproteins in biofluids from hip replacement patients

    DEFF Research Database (Denmark)

    Löschner, Katrin; Harrington, Chris F.; Kearney, Jacque-Lucca

    2015-01-01

    Hip replacements are used to improve the quality of life of people with orthopaedic conditions, but the use of metal-on-metal (MoM) arthroplasty has led to poor outcomes for some patients. These problems are related to the generation of micro- to nanosized metal wear particles containing Cr, Co o...

  20. Design and Optimization of Sinusoidal Formed Femur Prosthesis

    Directory of Open Access Journals (Sweden)

    Ahmet Zafer ŞENALP

    2015-01-01

    Full Text Available One of the major problems in hip replacement surgery is the hip replacement loosening. Hip replacement loosening occurs over time after the surgery and it is related to the discretization between the bone cement and prosthesis. The underlying factors of this situation are the stress occurring in the bone cement and the shape of the prosthesis. In this study, cortical and trabecular layers of the femur, bone cement and prosthesis were modeled. The models of bone cement and prosthesis were constructed parametrically and two different sinusoidal formed prostheses were developed unlike the former prostheses shapes. Analyses were conducted for these two different sinusoidal forms by using finite element method and optimization was conducted to obtain the appropriate prosthesis stem shape and bone cement thickness by using parametric modeling in finite element analyses. For finite element analyses and optimization, Ansys Workbench software was used and analyses were conducted for 316LS stainless steel material. Finally, the optimum prosthesis stem shape and bone cement thickness was determined by using the results of the analyses in the first stage

  1. Midterm results of "thrust plate" prosthesis.

    Science.gov (United States)

    Fink, Bernd; Wessel, Stephanie; Deuretzbacher, Georg; Protzen, Michael; Ruther, Wolfgang

    2007-08-01

    The aim of this investigation was to analyze the midterm results obtained with the metaphyseal fixation principle of the thrust plate prosthesis (TPP). Survival of 214 implants in 204 patients was analyzed. Clinical (Harris hip score) and radiologic examinations were carried out on 157 of 190 TPP with a postimplantation follow-up period of at least 5 years. Failure rate was 7.0% (9 aseptic and 6 septic loosening). Harris hip score increased from 36.9 +/- 13.5 points preoperatively to 91.2 +/- 13.1 points at follow-up. Eleven TPPs showed radiolucent lines not indicating prosthetic loosening. Thrust plate prosthesis is not an alternative to stemmed endoprostheses. It may be rarely indicated in very young patients where, because of their age, several revision operations can be expected.

  2. Reverse hybrid total hip arthroplasty

    DEFF Research Database (Denmark)

    Wangen, Helge; Havelin, Leif I.; Fenstad, Anne M

    2017-01-01

    . Patients and methods - From the NARA, we extracted data on reverse hybrid THAs from January 1, 2000 until December 31, 2013. 38,415 such hips were studied and compared with cemented THAs. The Kaplan-Meier method and Cox regression analyses were used to estimate the prosthesis survival and the relative risk...

  3. HIP IMPLANT ANALYSIS WITH CATIA

    Directory of Open Access Journals (Sweden)

    Florin CIOFU

    2017-12-01

    Full Text Available CATIA V5R16 is a product of Dassault Systemes, one of the most widely used CAD/CAM/ CAE systems worldwide, with applications in various fields, from the automotive, aerospace, automotive and medical industries. The paper aims to improve the technical, technological and medical knowledge related to the activity of the hip prosthesis.

  4. Chrome nitride coating reduces wear of small, spherical CrCoMo metal-on-metal articulations in a joint simulator.

    Science.gov (United States)

    Thorkildsen, R; Reigstad, O; Røkkum, M

    2017-03-01

    Metal-on-metal articulations have fallen out of favour in larger joint replacements, but are still used in smaller joints. Coating the articulation has been suggested as one way of reducing wear. We compared a standard 6 mm CrCoMo articulation designed for the carpometacarpal joint of the thumb with a chromium nitride-coated version after 512,000 cycles in a joint simulator. A total of 6 articulations in each group were tested with a unidirectional load of 5 kg in Ringer's solution. We found a statistically significant reduction in weight loss, amount of metallic wear produced and volumetric wear for the chromium nitride-coated articulation. Our findings support the use of chromium nitride coating in order to minimize the amount of metallic wear produced.

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

    Directory of Open Access Journals (Sweden)

    S.A. Arias

    2013-12-01

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

  6. Criterio de predicción de la vida útil de la prótesis total de cadera en función de la falla del cemento en el componente femoral. // Life prediction criteria of hip prosthesis according to cement failure in femoral component.

    Directory of Open Access Journals (Sweden)

    G. García del pino

    2002-09-01

    Full Text Available En este trabajo se utiliza el Método de los Elementos Finitos para estudiar la combinación de diferentes parámetros, y suinfluencia en la vida útil de la prótesis total de cadera utilizando como criterio la falla del cemento que une estas prótesis alfémur, debido a que este tipo de falla es una de las fallas que mas provoca la perdida de la implantación. Los parámetrosestudiados aquí fueron el tipo de material del vástago de la prótesis dado por su modulo de elasticidad, la calidad del huesodada por la densidad y las cargas simulando diferentes actividades físicas y diferentes pesos del cuerpo.Los resultados obtenidos a través del Método de los Elementos Finitos, fueron procesados utilizando rutinas creadas enlenguaje C y técnicas de estadística, determinando las variables más influyentes y los valores más favorables para obteneruna transmisión apropiada de cargas, que garanticen una vida útil mayor.Palabras claves: biomecánica, ortopedia, elementos finitos, modulación__________________________________________________________________AbstractIn this paper the Finite Element Method is employ in order to study different parameters combination and their influence inthe duration of total hip prosthesis, taking as decision criteria the failure of cement that keep together femur and prosthesis,taking in account that this is the most common cause of implantation lost. The target parameters were: shank prosthesismaterial given by elasticity modulus, bone quality given by density, and finally, loads simulating different physicalactivities and body weight. The results were processed by means of statistical techniques and C language routines allowingto obtain the more influent variables to a proper load transmission and greater useful prosthesis life.Key words: Biomechanics, orthopaedic, finite elements, modulation

  7. Do large heads enhance stability and restore native anatomy in primary total hip arthroplasty?

    Science.gov (United States)

    Lombardi, Adolph V; Skeels, Michael D; Berend, Keith R; Adams, Joanne B; Franchi, Orlando J

    2011-06-01

    Dislocation remains a serious complication in hip arthroplasty. Resurfacing proponents tout anatomic femoral head restoration as an advantage over total hip arthroplasty. However, advances in bearings have expanded prosthetic head options from traditional sizes of 22, 26, 28, and 32 mm to diameters as large as 60 mm. Large heads reportedly enhance stability owing to increased range of motion before impingement and increased jump distance to subluxation. Available larger diameter material combinations include metal- or ceramic-on-highly crosslinked polyethylene and metal-on-metal, each with distinct advantages and disadvantages. We sought to determine (1) if using larger diameter heads has lowered our dislocation rate; and (2) how closely an anatomic metal-on-metal bearing with diameters to 60 mm replicates native femoral head size. We retrospectively reviewed 2020 primary arthroplasties performed with large heads (≥ 36 mm) in 1748 patients and noted dislocation incidence. In a prospective subset of 89 cases using anatomic heads, native femoral head diameter was measured intraoperatively with calipers by an independent observer and later compared with implanted size. One dislocation has occurred in 2020 hips for an incidence of 0.05%. The prosthetic head averaged 0.7 mm larger than the native head with 68 of 89 (76%) reconstructed to within ± 2 mm of native size. Larger diameter heads have contributed to lower dislocation rates and large-diameter metal-on-metal articulation can provide close anatomic restoration in primary THA.

  8. A Randomized Seven-Year Study on Performance of the Stemmed Metal M2a-Magnum and Ceramic C2a-Taper, and the Resurfacing ReCap Hip Implants

    DEFF Research Database (Denmark)

    Borgwardt, Arne; Borgwardt, Lotte; Zerahn, Bo

    2018-01-01

    BACKGROUND: The large-diameter metal-on-metal hip prostheses were expected to have low wear and reduced dislocation rate compared to the traditional metal-on-polyethylene implants. We compare 2 such prostheses, the ReCap resurfacing implant and the M2a-Magnum stemmed implant, with the C2a ceramic...

  9. Histologic analysis of a retrieved hydroxyapatite-coated femoral prosthesis

    DEFF Research Database (Denmark)

    Søballe, K; Gotfredsen, K; Brockstedt-Rasmussen, H

    1991-01-01

    A hydroxyapatite-coated hip hemi-prosthesis was retrieved from a 98-year-old osteoporotic woman 12 weeks after implantation. Histologic analysis revealed bone and fibrous tissue almost evenly distributed around the surface of the implant circumference. Quantitative histologic analysis showed...

  10. Results of total hip arthroplasty using a bionic hip stem.

    Science.gov (United States)

    Fokter, Samo K; Sarler, Taras; Strahovnik, Andrej; Repše-Fokter, Alenka

    2015-06-01

    The trabecular-orientated bionic hip stem was designed to mimic the natural force transmission through the femur in total hip arthroplasty, resulting in supposedly longer prosthesis survivability. The aim of this study was to compare the second-generation bionic hip stem to a standard uncemented hip stem. A group of 18 patients (21 hips) who underwent total hip arthroplasty with a bionic stem (bionic group) was compared with a historic group of 12 patients (12 hips) treated with standard anatomic hip stem (control group). During the first year after the procedure, the densitometric measurements of the bone around the prosthesis were taken. Radiographic and clinical assessments were additionally performed preoperatively and at the three month, six month, one year and three year follow-ups in the bionic group. In the bionic group, one patient was revised for aseptic loosening and 16 patients (19 hips) were available to the final follow-up. A significant decrease of bone mineral density was found in Gruen zones 3, 4 and 5 in the bionic group, and in zone 7 in both groups. The bionic group had a significantly higher bone mineral density in Gruen zone 1 at the one year follow-up. At the final follow-up, all prostheses were radiologically stable in both groups. Provided that a good implant position is achieved, comparable short-term results can be obtained using a bionic stem. Still, a decrease of bone mineral density in Gruen zone 7 occurred in both groups. Further studies are required to determine survivability of the bionic stem.

  11. 99m technetium-MDP bone scintigraphy in evaluation of painful joint prosthesis

    International Nuclear Information System (INIS)

    Milosevic, D.; Jaukovic, M.; Jaukovic, Lj.; Ajdinovic, B.

    2004-01-01

    In addition of clinical evaluation and x-ray radiography, the diagnosis of a loose joint prosthesis is often made by nuclear medicine imaging techniques. Differentiation between loosening and infected prosthesis is important for better treatment of those patients. Aim: The aim of this study was to reevaluate the scintigraphic patterns in patients with painful hip of knee arthroplasty. Material and Method: From 1996. to 2003. forty patients aged 49-78 years were referred for evaluation of possible loosening/infection joint prosthesis: 36 pts with 39 total/ partial hip prosthesis, 1 pt with knee prosthesis and 3 pts with history of previously extracted hip prosthesis due to infection. Whole body acquisition had been performed with a single head gamma camera three hours after the injection of 740 MBq 99m Tc-MDP. Scans were classified as: positive for loosening if abnormal uptake was shown at the tip of the prosthesis; positive for infection if diffuse abnormal uptake was shown around the implant; negative and indeterminate scans. Scintigraphic findings were compared to clinical follow up, histology or cultures. Results: Positive findings were found in 17 bone scans strongly suggesting loosening in 10 cases, infection of prosthesis in 4 cases and both loosening/infection in 3 cases. Bone scintigraphy was normal in 11pts. Scans of three pts with previously extracted hip prosthesis and scheduled for reimplatation, showed inhomogeneously and mildly increased uptake in femur. Most of scans classified as indeterminate (n=12) showed slightly increased tracer uptake in region of acetabular roof, greater or lesser tho chanter, suggesting bone remodeling due to the presence of implant, rather than loosening. Conclusion: 99m Tc-MDP bone scintigraphy had a significant role in assessing the painful joint prosthesis. Complementary diagnostic procedures should be considered in indeterminate scintiscans. (authors)

  12. The current state of bearing surfaces in total hip replacement.

    Science.gov (United States)

    Rajpura, A; Kendoff, D; Board, T N

    2014-02-01

    We reviewed the literature on the currently available choices of bearing surface in total hip replacement (THR). We present a detailed description of the properties of articulating surfaces review the understanding of the advantages and disadvantages of existing bearing couples. Recent technological developments in the field of polyethylene and ceramics have altered the risk of fracture and the rate of wear, although the use of metal-on-metal bearings has largely fallen out of favour, owing to concerns about reactions to metal debris. As expected, all bearing surface combinations have advantages and disadvantages. A patient-based approach is recommended, balancing the risks of different options against an individual's functional demands.

  13. Detection of incorrect manufacturer labelling of hip components

    Energy Technology Data Exchange (ETDEWEB)

    Durand-Hill, Matthieu; Henckel, Johann; Skinner, John; Hart, Alister [University College London, Institute of Orthopaedics, London (United Kingdom); Burwell, Matthew [Royal United Hospital, Bath (United Kingdom)

    2017-01-15

    We describe the case of a 53-year-old man who underwent a left metal-on-metal hip resurfacing in 2015. Component size mismatch (CSM) was suspected because of the patient's immediate post-operative mechanical symptoms and high metal ion levels. Surgical notes indicated the appropriate combinations of implants were used. However, we detected a mismatch using computed tomography. Revision was performed and subsequent measurements of explanted components confirmed the mismatch. To our knowledge, this case is the first report of a CT method being used in a patient to pre-operatively identify CSM. (orig.)

  14. [Survey on the use and behaviour of metal-metal hip replacements in Spain].

    Science.gov (United States)

    Calcerrada, N; Fernández-Vega, A; Valls-León, C; Garcia-Cimbrelo, E

    2016-01-01

    Following medical device alerts published in different countries of problems with metal-on-metal total hip replacements, the Spanish Agency of Medicines and Medical Devices (AEMPS) in collaboration with the Spanish Hip Society Surgery designed a national survey to gather information on the use and behaviour of these hip implants. The survey consisted of a questionnaire sent by e-mail to 283 clinical centre recipients of metal-on-metal hips to be filled in by surgeons with expertise in the field. A total of 257 questionnaires were completed. The response rate of the clinical centres was 36.7%. A total of 97.7% of the responses reported that clinical and radiological follow-ups are carried out, and 79.6% undertook metal ion analyses (chromium and cobalt). A large majority (83.6%) of the responders who had who used surface implants, and 70% of those with large-head implants reported peri-operative complications. The most common complication was pain (25% with surface implants and 30.8% with large-head implants). Currently 80.8% of those responding were considering abandoning implanting of these hip replacements. Despite the many limitations to this study, the survey has allowed us to obtain in a quick first view of the implant scenario of Metal on Metal hip implants in Spain, and to determine the type of patient implanted, the time of implantation, and the experience/expertise of the surgeons, and the type of follow-up carried out. Copyright © 2015 SECOT. Published by Elsevier Espana. All rights reserved.

  15. A biomechanical comparison of the thrust plate prosthesis and a stemmed prosthesis.

    Science.gov (United States)

    Karatosun, Vasfi; Unver, Bayram; Gultekin, Alper; Gunal, Izge

    2011-01-01

    The thrust plate prosthesis (TPP) is a neck preserving femoral component in total hip arthroplasty (THA) which may facilitate more precise biomechanical reconstruction of the hip. The purpose of this study was to compare the biomechanical results of the TPP with a conventional THA. We compared anteroposterior radiographs from 60 patients who had undergone cementless THA, with 44 who had undergone a TPP. We measured the hip centre of rotation, femoral offset, limb length, and neck-shaft angle. The horizontal hip centre of rotation, vertical femoral offset, limb length and neck-shaft angle measurements showed a significant difference (phip centre of rotation and horizontal femoral offset measurements were different only in TPP patients when compared with preoperative values (phip centre of rotation displayed a significant difference (p=0.003) in favor of the THA. Therefore, we found no difference in restoring the biomechanics of the hip using the two methods, and only the horizontal hip centre of rotation restoration favoured the THA. Our findings indicate that the TPP does not produce more accurate restoration of leg length or offset. Reproduction of hip mechanics after TPP may not be as good as has been suggested.

  16. Custom hip prostheses by integrating CAD and casting technology

    Science.gov (United States)

    Silva, Pedro F.; Leal, Nuno; Neto, Rui J.; Lino, F. Jorge; Reis, Ana

    2012-09-01

    Total Hip Arthroplasty (THA) is a surgical intervention that is being achieving high rates of success, leaving room to research on long run durability, patient comfort and costs reduction. Even so, up to the present, little research has been done to improve the method of manufacturing customized prosthesis. The common customized prostheses are made by full machining. This document presents a different approach methodology which combines the study of medical images, through CAD (Computer Aided Design) software, SLadditive manufacturing, ceramic shell manufacture, precision foundry with Titanium alloys and Computer Aided Manufacturing (CAM). The goal is to achieve the best comfort for the patient, stress distribution and the maximum lifetime of the prosthesis produced by this integrated methodology. The way to achieve this desiderate is to make custom hip prosthesis which are adapted to each patient needs and natural physiognomy. Not only the process is reliable, but also represents a cost reduction comparing to the conventional full machined custom hip prosthesis.

  17. Hip Replacement

    Science.gov (United States)

    Hip replacement is surgery for people with severe hip damage. The most common cause of damage is osteoarthritis. Osteoarthritis ... pain medicines, and exercise haven't helped, hip replacement surgery might be an option for you. During ...

  18. Hip or knee replacement - before - what to ask your doctor

    Science.gov (United States)

    ... replace all or part of your hip or knee joint with an artificial device (a prosthesis). Below are some questions you may want to ask your health care provider to help you prepare for your hip or knee replacement. Questions Is joint replacement the best treatment ...

  19. The Angelchik prosthesis

    International Nuclear Information System (INIS)

    Fargnoli, R.; Bozza, A.; Magnoli, A.; Villari, N.; Pernice, L.M.; Andreoli, F.; Lombardi, P.

    1989-01-01

    The Angelchik prosthesis is used in the surgical treatment of gastroesophageal reflux. Operated patients are preliminary examined with imaging techniques, but manometric and acidometric techniques are also used. Although the conventional esophagogram still maintains its diagnostic significance, Computed Tomography (CT) has become the first-choice imaging modality. CT allows the correct evaluation of both the state of the prosthesis and its relationship to the esophagus and gastric fundus. The possible postoperative complications following an incorrect placement of the prosthesis can be accurately diagnosed too. The authors report their experience in the study of 5 patients examined with both conventional radiology and CT

  20. [Midterm results and revisions of the thrust plate prosthesis (TPP)].

    Science.gov (United States)

    Ishaque, B A; Wienbeck, S; Stürz, H

    2004-01-01

    Although already in use for 20 years, the concept of the metaphyseal anchored thrust plate prosthesis has not yet gained general acceptance. Clinical and radiological follow-up examinations were carried out 5 to 8 years after implantation of a TPP. We tried to answer the question if the metaphyseal anchorage of the cement-less TPP is equal to a diaphyseal anchorage of a cement-less stem prosthesis and to define the advantages of the TPP. We included 170 of the patients from our clinic with an implanted TPP in this study. Furthermore we reviewed the results of 30 revision hip arthroplasties of the TPP. The clinical examination were carried out using the Harris hip score while the radiological examinations were performed on the basis of predefined criteria. We found good clinical results. The preoperative Harris score of 48.7 increased to 93.7 at 24 months postoperatively. Radiolucencies were detected and were of varying relevance in dependence on their localization. The Kaplan-Meier survival analysis at 8 years was 90.5 %. The clinical results after changing the TPP were also good to excellent. The mean Harris hip score was 87.3. Our study suggests that in spite of a slightly higher aseptic loosening rate in comparison to the cement-less stem prosthesis, the thrust plate prosthesis proved to be worthwhile. On the basis of previous experience we assume that the TPP is a good alternative implant especially for young patients.

  1. Systemic cobalt toxicity from total hip arthroplasties: review of a rare condition Part 1 - history, mechanism, measurements, and pathophysiology.

    Science.gov (United States)

    Cheung, A C; Banerjee, S; Cherian, J J; Wong, F; Butany, J; Gilbert, C; Overgaard, C; Syed, K; Zywiel, M G; Jacobs, J J; Mont, M A

    2016-01-01

    Recently, the use of metal-on-metal articulations in total hip arthroplasty (THA) has led to an increase in adverse events owing to local soft-tissue reactions from metal ions and wear debris. While the majority of these implants perform well, it has been increasingly recognised that a small proportion of patients may develop complications secondary to systemic cobalt toxicity when these implants fail. However, distinguishing true toxicity from benign elevations in cobalt ion levels can be challenging. The purpose of this two part series is to review the use of cobalt alloys in THA and to highlight the following related topics of interest: mechanisms of cobalt ion release and their measurement, definitions of pathological cobalt ion levels, and the pathophysiology, risk factors and treatment of cobalt toxicity. Historically, these metal-on-metal arthroplasties are composed of a chromium-cobalt articulation. The release of cobalt is due to the mechanical and oxidative stresses placed on the prosthetic joint. It exerts its pathological effects through direct cellular toxicity. This manuscript will highlight the pathophysiology of cobalt toxicity in patients with metal-on-metal hip arthroplasties. Patients with new or evolving hip symptoms with a prior history of THA warrant orthopaedic surgical evaluation. Increased awareness of the range of systemic symptoms associated with cobalt toxicity, coupled with prompt orthopaedic intervention, may forestall the development of further complications. ©2016 The British Editorial Society of Bone & Joint Surgery.

  2. Radiography, radionuclide imaging, and asthrography in the evaluation of total hip and knee replacement

    International Nuclear Information System (INIS)

    Gelman, M.I.; Coleman, R.E.; Stevens, P.M.; Davey, B.W.

    1978-01-01

    Twenty patients with 21 total joint replacements including 17 hips and 4 knees were studied by plain film radiography, radionuclide imaging, and subtraction arthrography to evaluate these procedures for assessing prosthetic complications. Surgery was performed in 14 patients and confirmed loosening of 8 femoral and 7 acetabular hip prosthesis components and 1 femoral and 4 tibial knee prosthesis components. Plain films suggested loosening of only 9 hip components and no knee components. In contrast, radionuclide imaging and subtraction arthrography were considerably more effective in demonstrating loosening as well as other causes of the painful total joint prosthesis

  3. Formation of a pseudotumor in total hip arthroplasty using a tribological metal-polyethylene pair

    Directory of Open Access Journals (Sweden)

    Lorenzo Fagotti

    2015-12-01

    Full Text Available ABSTRACT The aim here was to report a case of a young adult patient who evolved with tumor formation in the left thigh, 14 years after revision surgery on hip arthroplasty. Davies in 2005 made the first description of this disease in patients undergoing metal-on-metal hip arthroplasty. Over the last decade, however, pseudotumors around metal-on-polyethylene surfaces have become more prevalent. Our patient presented with increased volume of the left thigh 8 years after hip arthroplasty revision surgery. Two years before the arising of the tumor in the thigh, a nodule in the inguinal region was investigated to rule out a malignant neoplastic process, but the results were inconclusive. The main preoperative complaints were pain, functional limitation and marked reduction in the range of motion of the left hip. Plain radiographs showed loosening of acetabular and femoral, and a large mass between the muscle planes was revealed through magnetic resonance imaging of the left thigh. The surgical procedure consisted of resection of the lesion and removal of the components through lateral approach. In respect of total hip arthroplasty, pseudotumors are benign neoplasms in which the bearing surface consists of metal-on-metal, but they can also occur in different tribological pairs, as presented in this case.

  4. Hip Fracture

    Science.gov (United States)

    ... hip fractures in people of all ages. In older adults, a hip fracture is most often a result of a fall from a standing height. In people with very weak bones, a hip fracture can occur simply by standing on the leg and twisting. Risk factors The rate of hip fractures increases substantially with ...

  5. Clinical and functional outcomes of the saddle prosthesis.

    Science.gov (United States)

    Donati, D; D'Apote, G; Boschi, M; Cevolani, L; Benedetti, M G

    2012-06-01

    The implantation of a saddle prosthesis after resection of a pelvic tumor has been proposed as a simple method of reconstruction that provides good stability and reduces the surgical time, thus limits the onset of intraoperative complications. There are no studies in the literature of patients evaluated using gait analysis after being implanted with a saddle prosthesis. The present study is a retrospective case review aimed at illustrating long-term clinical and functional findings in tumor patients reconstructed with a saddle prosthesis. A series of 15 patients who received pelvic reconstruction with a saddle prosthesis were retrospectively reviewed in terms of clinical, radiographic, and functional evaluations. Two patients were additionally assessed by gait analysis. Long-term functional follow-up was achieved in only 6 patients, and ranged from 97 to 167 months. Function was found to be rather impaired, as a mean of only 57 % of normal activity was restored. Gait analysis demonstrated that the implant had poor biomechanics, as characterized by very limited hip motion. Though the saddle prosthesis was proposed as advance in tumor-related pelvic surgery, the present study indicates that it yields unsatisfactory clinical and functional results due to both clinical complications and the poor biomechanics of the device. The use of a saddle prosthesis in tumor surgery did not provide satisfactory results in long-term follow-up. It is no longer implanted at our institute, and is currently considered a "salvage technique."

  6. Re-infection outcomes following one- and two-stage surgical revision of infected hip prosthesis in unselected patients: protocol for a systematic review and an individual participant data meta-analysis

    OpenAIRE

    Kunutsor, Setor K; Whitehouse, Michael R; Webb, Jason; Toms, Andrew; Stockley, Ian; Taylor, Adrian; Jones, Stephen; Wilson, Matthew; Burston, Ben; Board, Tim; Whittaker, John-Paul; Blom, Ashley W; Beswick, Andrew D

    2015-01-01

    Background Several aggregate published reviews have compared the effectiveness of one- and two-stage surgical revision to prevent re-infection following prosthetic hip infection and have reported inconsistent results. In addition, there were several features of these previous reviews which limited the validity of the findings. In the absence of a well-designed clinical trial, we propose the Global Infection Orthopaedic Management (INFORM) collaboration, a worldwide collaborative systematic re...

  7. Usefulness of positron emission tomography (TEP) in the assessment of osteo-articular prosthesis

    International Nuclear Information System (INIS)

    Maldonado, A.; Suarez, J.P.; Dominguez, M.L.

    2004-01-01

    Joint arthroplasty is performed with increasing frequency as the population ages. Loosening or infection of the prosthesis is a relatively common event that can limit the lifetime of a prosthesis. Accuracy differentiation between aseptic and septic loosening of the prosthesis remains a challenge because of the consequences for patient management. Moreover, an early diagnosis of infected hip prosthesis is very important for optimal and cost-effective management. Various approaches have developed to visualize infection and inflammation by nuclear medicine techniques. Recently positron emission tomography (PET) with fluorine-l8 labelled 2 fluoro-2-deoxyglucose ( 18 F-FDG) has been shown to delineate infectious and inflammatory foci with high sensitivity owing to the increased glucose metabolism in inflammatory cells. In this paper we review the role of FDG-PET in this common differential diagnosis in patients with total knee and hip prostheses. Different patterns of FDG-PET interpretation have been described as wed as methodological aspects. (author)

  8. Early loosening and secondary dislocation due to a broken trochanteric osteotomy wire following a Charnley total hip arthroplasty: a case report

    OpenAIRE

    Shahin, Yousef; Choudhary, Rakesh; Al-Naser, Saeed; Mullins, Mark

    2009-01-01

    We report a case of interposition of a broken trochanteric wire in the hip joint. This caused early wear of the prosthesis and dislocation of the Charnley total hip arthroplasty. The patient was treated with a revision total hip arthroplasty. This rare complication should be taken into consideration when performing a trochanteric osteotomy fixation with wiring in Charnley total hip arthroplasty.

  9. Thrust plate prosthesis for proximal femoral deformity: a series of 15 patients

    OpenAIRE

    Karatosun, Vasfi; Ünver, Bayram; Gultekin, Alper; Gunal, Izge

    2011-01-01

    Objectives: Patients with coxarthrosis and proximal femoral deformity experience problems with total hip arthroplasty. A custom-made prosthesis or a proximal osteotomy is required for such cases, and these also increase the rate of complications. The purpose of this study was to evaluate the results of the thrust plate prosthesis (TPP) in patients with deformity of the proximal femur. Methods: Fifteen patients (7 females, 8 males) with a mean age of 56.4 years (range 19-75 years) at the...

  10. Hip pain

    Science.gov (United States)

    ... from a chair, walking, climbing stairs, and driving Hamstring strain Iliotibial band syndrome Hip flexor strain Hip ... and cool down afterward. Stretch your quadriceps and hamstrings. Avoid running straight down hills. Walk down instead. ...

  11. Medium-term results of thrust plate prostheses for osteoarthritis of the hip.

    Science.gov (United States)

    Karatosun, Vasfi; Gunal, Izge; Unver, Bayram

    2005-01-01

    We retrospectively evaluated the results of 61 patients (67 hips) who underwent total hip arthroplasty using the thrust plate prosthesis (TPP) for osteoarthritis of the hip joint. All patients were followed-up at least two years (mean: 37.2 months). Mean preoperative Harris hip score improved from 45.8 (SD: 13.5) to 94.9 (SD: 5.4) points postoperatively. Revision was performed in five cases. Medium-term results of TPP are promising.

  12. Design of a technique for the radiotherapy treatment of patients of prostate with bilateral prosthetic hip

    International Nuclear Information System (INIS)

    Camacho, C.; Perez-Alija, J.; Olivares, S.; Loscos, S.; Pedro, A.

    2013-01-01

    The design of the plan of treatment of patients who have to undergo radical radiotherapy of prostate and that incorporate some sort of hip prosthesis is usually complex. the case of a patient's prostatic bed with bilateral hip prosthesis to assess radical radiotherapy to the 70Gy in bed. The objective of this paper is to present the chosen technique designed for this treatment. (Author)

  13. Radiological and scintigraphic evaluation of hip prostheses

    International Nuclear Information System (INIS)

    Bessler, W.; Schaub, W.

    1979-01-01

    The radiological findings following the introduction of hip prostheses are often equivocal. Additional bone scintigrams often provide important information for the evaluation of the prostheses. 1. An unstable hip prosthesis is characterised by abnormal uptake in bone, due to static and mechanical stress. 2. A positive scintigram does not necessarily indicate instability of the prosthesis. Increased uptake may also be due to inflammatory bone changes, healing, bone replacement, abnormal local stresses or soft tissue calcification. 3. In evaluating the scintigram one must take account not only of the intensity of isotope uptake, but also its distribution and exact localisation. 4. It is essential to compare the scintigram with the radiograph. Radiological features of possible instability become diagnostic if they correspond with appropriate increased radioactivity. If the latter is absent, the of instability remains doubtful. 5. In some cases early loosening of the stem of the prosthesis can be diagnosed while the radiograph is still negative. Increased radioactivity in the acetabulum is frequently seen in the presence of a stable acetabular prosthesis and must be interpreted with caution as a sign of loosening of the prosthesis. (orig.) [de

  14. Radiography, radionuclide imaging, and asthrography in the evaluation of total hip and knee replacement. [/sup 99m/Tc-phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Gelman, M.I.; Coleman, R.E.; Stevens, P.M.; Davey, B.W.

    1978-09-01

    Twenty patients with 21 total joint replacements including 17 hips and 4 knees were studied by plain film radiography, radionuclide imaging, and subtraction arthrography to evaluate these procedures for assessing prosthetic complications. Surgery was performed in 14 patients and confirmed loosening of 8 femoral and 7 acetabular hip prosthesis components and 1 femoral and 4 tibial knee prosthesis components. Plain films suggested loosening of only 9 hip components and no knee components. In contrast, radionuclide imaging and subtraction arthrography were considerably more effective in demonstrating loosening as well as other causes of the painful total joint prosthesis.

  15. Hip joint replacement

    Science.gov (United States)

    Hip arthroplasty; Total hip replacement; Hip hemiarthroplasty; Arthritis - hip replacement; Osteoarthritis - hip replacement ... your activities. Most of the time, hip joint replacement is done in people age 60 and older. ...

  16. Hip resurfacing: history, current status, and future.

    Science.gov (United States)

    Amstutz, Harlan C; Le Duff, Michel J

    2015-01-01

    Hip resurfacing arthroplasty (HRA) presents several advantages over conventional total hip arthroplasty (THA), including conservation and preservation of bone, reduced risk of dislocation, easy replication of hip biomechanics and easy revision if needed. It is a particularly appealing procedure for young patients. HRA has been performed for over 40 years following the same technological advances as THA. The bearing material used by most designs is metal-on-metal (MoM), which has the best compromise between strength and wear properties. However, MoM HRA has a specific set of possible complications. Aseptic femoral failures were initially the most prevalent cause for revision but progress in patient selection and surgical technique seem to have resolved this problem. Wear-related failures (high metal ion levels and adverse local tissue reactions) are now the main concern, and are essentially associated with poor acetabular component design and orientation, to which MoM is more sensitive than other bearing materials. The concept of functional coverage is key to understanding how MoM bearings are affected by edge wear. Only a 3-D assessment of cup position (e.g., the contact patch to rim distance) provides the necessary information to determine the role of cup positioning in relationship with abnormal bearing wear.The concept of hip resurfacing is more valid today than ever as the age of the patients in need of hip arthroplasty keeps getting lower. The recent publication of several excellent long-term survivorship results suggests that selection of a well-designed resurfacing system and accuracy in the placement of the cup can achieve long-term durability.

  17. Cardiac transplant due to metal toxicity associated with hip arthroplasty

    Directory of Open Access Journals (Sweden)

    Sheldon Moniz, MBBS (UWA

    2017-09-01

    Full Text Available Concerns regarding metal-on-metal (MoM bearing couples in total hip arthroplasty are well documented in the literature with cobalt (Co and chromium (Cr toxicity causing a range of both local and systemic adverse reactions. We describe the case of a patient undergoing cardiac transplantation as a direct result of Co and Cr toxicity following a MoM hip replacement. Poor implant positioning led to catastrophic wear generating abundant wear particles leading to Co and Cr toxicity, metallosis, bony destruction, elevated metal ion levels, and adverse biological responses. Systemic symptoms continued for 3 years following cardiac transplantation with resolution only after revision hip arthroplasty. There was no realization in the initial cardiac assessment and subsequent transplant workup that the hip replacement was the likely cause of the cardiac failure, and the hip replacement was not recognized as the cause until years after the heart transplant. This case highlights the need for clinicians to be aware of systemic MoM complications as well as the importance of positioning when using these prostheses.

  18. Jogging after total hip arthroplasty.

    Science.gov (United States)

    Abe, Hirohito; Sakai, Takashi; Nishii, Takashi; Takao, Masaki; Nakamura, Nobuo; Sugano, Nobuhiko

    2014-01-01

    Jogging has been classified as a high-impact sport, and jogging after total hip arthroplasty (THA) has not been well documented. To investigate the participation rate for postoperative jogging as well as jogging parameters and the influence of jogging on implant stability and bearing wear. Case-control study; Level of evidence, 3. Included in this study were 804 hips in 608 patients (85 men, 523 women) who underwent THA between 2005 and 2011 with follow-up longer than 1 year. The mean patient age was 62 years (range, 26-98 years), and mean follow-up duration was 4.8 years (range, 2.3-7.8 years). Hip resurfacing arthroplasty (HRA) was performed in 81 patients and conventional THA in 527 patients. During routine postsurgical visits, patients were given a questionnaire concerning preoperative and postoperative jogging routines. For joggers, frequency, distance, duration, and velocity of jogging were recorded. Patients who did not jog postoperatively were asked to provide reasons for not jogging. Radiographs concerning implant migration and polyethylene wear were evaluated with specialized software, and serum cobalt and chromium ion concentrations were investigated for patients with metal-on-metal articulation. A total of 33 patients (5.4%) performed jogging preoperatively, and 23 patients (3.8%) performed jogging postoperatively. Of the 23 who jogged postoperatively, conventional THA was performed in 13 patients and HRA in 10 patients. Postoperatively, joggers trained a mean of 4 times (range, 1-7 times) per week, covering a mean distance of 3.6 km (range, 0.5-15 km) in a mean time of 29 minutes (range, 5-90 minutes) per session and at a mean speed of 7.7 km/h (range, 3-18 km/h). No patient complained of pain or showed serum cobalt and chromium ion elevation greater than 7 ppb. No hip showed loosening, abnormal component migration, or excessive wear at a mean 5-year follow-up. There were 74 postoperative non-joggers with an interest in jogging. The reasons given for

  19. Outcome measures of bipolar hip arthroplasty for atraumatic hip disorders - A preliminary report

    Directory of Open Access Journals (Sweden)

    Dudani Baldev

    2005-01-01

    Full Text Available Background: Bipolar hip arthroplasty was devised for fracture neck femur in elderly patients. Subsequently, indications have been expanded to include conditions affecting acetabulum like rheumatoid arthritis, osteoarthritis and avascular necrosis of femoral head. Materials and methods: We have studied the results of bipolar hip arthroplasty in 38 such patients, with severely involved acetabulum due to rheumatoid arthritis, avascular necrosis of femoral head and primary osteoarthritis. Acetabulum was reamed to get a tight ′equatorial′ or ′rim′ fit of the prosthesis. Prosthesis selected was 1 mm bigger than the maximum size of reamer used. Cement was used in femur whenever there was marked osteoporosis or wide medullary canal. Post operatively all patients were regularly screened for pain, range of movement, protrusio acetabuli, loosening / sinking of prosthesis and radiographic assessment of movement in the two bearings of prosthesis. Results: Overall results achieved were good to excellent in 80% of patients. Conclusions: The ultimate outcome is comparable to total hip arthroplasty. The added advantage is of low cost, simplicity of procedure and easy future revision.

  20. Monte Carlo dose calculations for phantoms with hip prostheses

    International Nuclear Information System (INIS)

    Bazalova, M; Verhaegen, F; Coolens, C; Childs, P; Cury, F; Beaulieu, L

    2008-01-01

    Computed tomography (CT) images of patients with hip prostheses are severely degraded by metal streaking artefacts. The low image quality makes organ contouring more difficult and can result in large dose calculation errors when Monte Carlo (MC) techniques are used. In this work, the extent of streaking artefacts produced by three common hip prosthesis materials (Ti-alloy, stainless steel, and Co-Cr-Mo alloy) was studied. The prostheses were tested in a hypothetical prostate treatment with five 18 MV photon beams. The dose distributions for unilateral and bilateral prosthesis phantoms were calculated with the EGSnrc/DOSXYZnrc MC code. This was done in three phantom geometries: in the exact geometry, in the original CT geometry, and in an artefact-corrected geometry. The artefact-corrected geometry was created using a modified filtered back-projection correction technique. It was found that unilateral prosthesis phantoms do not show large dose calculation errors, as long as the beams miss the artefact-affected volume. This is possible to achieve in the case of unilateral prosthesis phantoms (except for the Co-Cr-Mo prosthesis which gives a 3% error) but not in the case of bilateral prosthesis phantoms. The largest dose discrepancies were obtained for the bilateral Co-Cr-Mo hip prosthesis phantom, up to 11% in some voxels within the prostate. The artefact correction algorithm worked well for all phantoms and resulted in dose calculation errors below 2%. In conclusion, a MC treatment plan should include an artefact correction algorithm when treating patients with hip prostheses

  1. The impact of surface and geometry on coefficient of friction of artificial hip joints.

    Science.gov (United States)

    Choudhury, Dipankar; Vrbka, Martin; Mamat, Azuddin Bin; Stavness, Ian; Roy, Chanchal K; Mootanah, Rajshree; Krupka, Ivan

    2017-08-01

    Coefficient of friction (COF) tests were conducted on 28-mm and 36-mm-diameter hip joint prostheses for four different material combinations, with or without the presence of Ultra High Molecular Weight Polyethylene (UHMWPE) particles using a novel pendulum hip simulator. The effects of three micro dimpled arrays on femoral head against a polyethylene and a metallic cup were also investigated. Clearance played a vital role in the COF of ceramic on polyethylene and ceramic on ceramic artificial hip joints. Micro dimpled metallic femoral heads yielded higher COF against a polyethylene cup; however, with metal on metal prostheses the dimpled arrays significantly reduced the COF. In situ images revealed evidence that the dimple arrays enhanced film formation, which was the main mechanism that contributed to reduced friction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. [Sir John Charnley and total hip arthroplasty].

    Science.gov (United States)

    Burgers, Paul T P W; van Gijn, Jan

    2011-01-01

    Sir John Charnley (1911-1982), pioneer of the total hip prosthesis, saved countless elderly people from immobility. During the Second World War he assisted Dudley Buxton, orthopaedic surgeon to the British armed forces in the Middle East, in developing new instruments and splints. After the war he first studied healing of bone fractures and the role of compression, and then completely dedicated himself to arthroplasty of the hip. Through countless experiments he found the optimal diameter for the head of the stainless steel prosthesis as well as the optimal polymer for the socket; he also advocated tight cementing of the shaft into the femur. Sir John Charnley received the Lasker Award in 1974 and was knighted in 1977.

  3. Short-Term Effect of Prosthesis Transforming Sensory Modalities on Walking in Stroke Patients with Hemiparesis

    Directory of Open Access Journals (Sweden)

    Dai Owaki

    2016-01-01

    Full Text Available Sensory impairments caused by neurological or physical disorders hamper kinesthesia, making rehabilitation difficult. In order to overcome this problem, we proposed and developed a novel biofeedback prosthesis called Auditory Foot for transforming sensory modalities, in which the sensor prosthesis transforms plantar sensations to auditory feedback signals. This study investigated the short-term effect of the auditory feedback prosthesis on walking in stroke patients with hemiparesis. To evaluate the effect, we compared four conditions of auditory feedback from plantar sensors at the heel and fifth metatarsal. We found significant differences in the maximum hip extension angle and ankle plantar flexor moment on the affected side during the stance phase, between conditions with and without auditory feedback signals. These results indicate that our sensory prosthesis could enhance walking performance in stroke patients with hemiparesis, resulting in effective short-term rehabilitation.

  4. Hip abductor moment arm - a mathematical analysis for proximal femoral replacement

    Directory of Open Access Journals (Sweden)

    Temple H Thomas

    2011-01-01

    Full Text Available Abstract Background Patients undergoing proximal femoral replacement for tumor resection often have compromised hip abductor muscles resulting in a Trendelenberg limp and hip instability. Commercially available proximal femoral prostheses offer several designs with varying sites of attachment for the abductor muscles, however, no analyses of these configurations have been performed to determine which design provides the longest moment arm for the hip abductor muscles during normal function. Methods This study analyzed hip abductor moment arm through hip adduction and abduction with a trigonometric mathematical model to evaluate the effects of alterations in anatomy and proximal femoral prosthesis design. Prosthesis dimensions were taken from technical schematics that were obtained from the prosthesis manufacturers. Manufacturers who contributed schematics for this investigation were Stryker Orthopaedics and Biomet. Results Superior and lateral displacement of the greater trochanter increased the hip abductor mechanical advantage for single-leg stance and adduction and preserved moment arm in the setting of Trendelenberg gait. Hip joint medialization resulted in less variance of the abductor moment arm through coronal motion. The Stryker GMRS endoprosthesis provided the longest moment arm in single-leg stance. Conclusions Hip abductor moment arm varies substantially throughout the hip's range of motion in the coronal plane. Selection of a proximal femur endoprosthesis with an abductor muscle insertion that is located superiorly and laterally will optimize hip abductor moment arm in single-leg stance compared to one located inferiorly or medially.

  5. Loose Metasul liner causing partial amputation of the neck of the femoral component.

    Science.gov (United States)

    McMurtrie, Andrew; Guha, Abhijit R; Wootton, James R

    2009-01-01

    The use of metal-on-metal bearings in total hip arthroplasty is becoming increasingly popular. Several authors have reported excellent medium- and long-term results after the use of the Metasul metal-on-metal articulation (Sulzer Medica, Winterthur, Switzerland). We report a case of a loose Metasul liner eroding the neck of the femoral component resulting in extensive metallosis and weakening of the prosthesis.

  6. Bone-preserving total hip arthroplasty in avascular necrosis of the hip-a matched-pairs analysis.

    Science.gov (United States)

    Merschin, David; Häne, Richard; Tohidnezhad, Mersedeh; Pufe, Thomas; Drescher, Wolf

    2018-03-22

    Short-stem hip arthroplasty has the potential advantage of femoral bone stock preservation, especially in view of the expected revisions in the often relatively young patients. Despite short-stem hip prosthesis are increasingly used for total hip arthroplasty, there are no sufficient mid- and long-term results especially for patients with avascular femoral head osteonecrosis. The present study investigates mid-term functional results as well as the revision rate following implantation of a short-stem prosthesis. In the period 06/2005 until 12/2013, a total of 351 short-stem hip prostheses were implanted. The study included 331 complete data sets. A retrospective analysis was performed using the Oxford Hip Score. All revisions were registered. In a total of 331 prostheses, the Oxford Hip Score was "excellent" in 66.2%, "good" in 12.7%, "fair" in 13.0%, and "poor" in 8.2% with a mean follow-up of 57.4 months (SD ± 29.8; range 24-115). In 26 cases, aseptic osteonecrosis of the hip was the indication (7.9%). The Oxford Hip Score was "excellent" in 66.7%, "good" in 0.0%, "fair" in 20.8%, and "poor" in 12.5%. The cumulated five year survival rate was 96.7%. In mid-term observation, the Metha® short-stem prosthesis shows no disadvantage in functional outcome and in survival time compared to a standard hip stem. Providing a correct indication, the Metha® short stem is a valuable option in total hip arthroplasty for younger patients with avascular osteonecrosis of the femoral head. Evaluation has shown no significant differences between aseptic osteonecrosis and other indications.

  7. [Progress of temporomandibular joint prosthesis].

    Science.gov (United States)

    Sun, Quan; Li, Kaide; Liu, Lei

    2014-08-01

    The anatomically and functionally complex nature of the temporomandibularjoint (TMJ) makes its reconstruction one of the most challenging tasks faced by surgeons who operate in the head and neck. TMJ prosthesis is one of the important techniques in the reconstruction of TMJ. The main indications for TMJ prosthesis include ankylosis, fractures of condylar that can't be fixed, trauma or tumor, end-stage TMJ disturbance, and TMJ dysplasia caused by Hallermann-Streiff syndrome. TMJ replacement aims to enhance the function of TMJ, alleviate pain, and prevent serious complications. TMJ prosthesis is advantageous in oral and maxillofacial surgery because it can imitate normal anatomic morphology and adhere to the host. Moreover, the use of other materials is no longer necessary and functional training can be started postoperatively at once, among others. Prosthetic materials have leading and promoting functions in the development of joint prosthesis. Good design, fit shape, and fixation are the necessary conditions for prosthesis to serve its function. Investigation of joint biomechanics is also necessary. With the rapid developments in material science, joint biomechanics, and other related subjects, TMJ prosthesis has been significantly improved in terms of its materials, design, fit shape, and fixation techniques. In addition, the development of TMJ prosthesis would expand its applications. This review intends to provide an overview about the progress and clinical application of TMJ prosthesis.

  8. Assessing the results of thrust plate prosthesis: a comparison of four different rating systems.

    Science.gov (United States)

    Unver, Bayram; Karatosun, Vasfi; Gunal, Izge

    2005-09-01

    To evaluate four rating systems designed to assess patients following provision of a thrust plate prosthesis. Sixty-one patients undergoing total hip replacement with thrust plate prosthesis. Patients were evaluated preoperatively and six months postoperatively by four different hip rating systems (Harris, Iowa, Charnley and Merle d'Aubigne), both on a categorical and on a numerical basis. Department of orthopaedics and traumatology in a university hospital. Patients were evaluated by four rating systems preoperatively and postoperatively either on a categorical or a numerical basis. All patients showed significant improvement after surgery in all rating systems. Although preoperative categorical evaluation revealed that the strongest correlation was between Charnley and Merle d'Aubigne scores (r = 0.876), numerical comparison of the rating systems showed strong correlation among all systems, both pre- and postoperatively. Responsiveness analysis revealed larger effect size for the Iowa and Harris hip scores. Our results suggest that hip rating systems should be compared numerically rather than by categorical evaluation and that the Iowa and Harris hip scores are more convenient in evaluating thrust plate prosthesis patients because they have larger effect sizes without floor and ceiling effects.

  9. Dislocation of total hip replacement in patients with fractures of the femoral neck

    OpenAIRE

    Enocson, Anders; Hedbeck, Carl-Johan; Tidermark, Jan; Pettersson, Hans; Ponzer, Sari; Lapidus, Lasse J

    2009-01-01

    Background Total hip replacement is increasingly used in active, relatively healthy elderly patients with fractures of the femoral neck. Dislocation of the prosthesis is a severe complication, and there is still controversy regarding the optimal surgical approach and its influence on stability. We analyzed factors influencing the stability of the total hip replacement, paying special attention to the surgical approach. Patients and methods We included 713 consecutive hips in a series of 698 p...

  10. Metal release from hip prostheses: cobalt and chromium toxicity and the role of the clinical laboratory.

    Science.gov (United States)

    Campbell, Jonathon R; Estey, Mathew P

    2013-01-01

    Individuals with advanced hip disease suffer from pain, impaired hip function, and decreased quality of life. Roughly one million metal-on-metal (MoM) hip prostheses have been implanted worldwide in order to ameliorate these issues. While most MoM hip replacements are successful, some patients suffer from serious adverse effects secondary to the release of metal debris due to implant wear and corrosion. MoM hip prostheses are comprised predominantly of cobalt and chromium, and the serum concentration of these metal ions has been shown to correlate with both implant wear and the accumulation of metal debris in the periprosthetic tissue. Consequently, measurement of cobalt and chromium concentrations may be useful in the assessment of implant function and the potential for adverse effects in the follow-up of patients with MoM hip prostheses. The purpose of this Mini Review is to describe the adverse biological consequences of metal release from hip prostheses, provide an overview of the clinical utility of cobalt and chromium measurement and the current recommendations for testing, and alert laboratorians and physicians to the many challenges associated with measuring these metal ions.

  11. Ipsilateral Fracture Shaft Femur with Neglected Dislocation of Prosthesis: A Case Report

    Directory of Open Access Journals (Sweden)

    Mantu Jain

    2013-10-01

    Full Text Available Introduction: Neglected hip dislocation is rare in today’s world and after prosthesis replacement even rarer finding. However such patients may not report to surgeons until they develop secondary complications. Management of such patient’s is a challenge to the treating surgeon and need to be tailored suiting to patient’s demands, expectations and constraints of financial resources. We did not find a similar case in the electronic and print media and therefore report this case which was innovatively managed. Case Report: A 60 year farmer presented with fracture shaft femur and ipsilateral dislocation prosthesis of right hip. He had a hemiarthroplasty done for fracture neck of femur in the past but used to walk with a lurch since he started to ambulate after discharge. However he was satisfied despite “some problems” which had caused shortening of his limb. The patient was informed of the various treatment options and their possible complications. He expressed his inability to afford a Total Hip Arthroplasty (THA at any stage and consented for other options discussed with him. The patient was positioned supine and adductor tenotomy done. Next he was positioned laterally and the fracture was fixed with heavy duty broad dynamic compression plate and screws. The wound was temporarily closed. Now through the previous scar via posterior approach the hip was exposed. The prosthesis was found to be firmly fixed to the proximal femur. The acetabulum was cleared with fibrous tissue. All attempts the prosthesis to relocate the prosthesis failed after several attempts and it was best decided to leave alone. Post operatively period was uneventful. At follow up he refused for any further manoeuvre in future inform of heavy traction and attempts to reduce the same. At one year when he was walking unaided and his X-rays showed that fracture had well united his SF-36 score was PCS – 49.6 and MCS – 51.9. Conclusion: Ipsilateral shaft femur fracture

  12. Joint prosthesis and method of bone fixation

    NARCIS (Netherlands)

    Oosterom, R.; Van der Pijl, A.J.; Bersee, H.E.N.; Van der Helm, F.C.; Herder, J.L.

    2006-01-01

    The invention relates to a joint prosthesis (10), for example, a knee joint or shoulder joint prosthesis comprising a first, socket-holding prosthesis part (11) for attachment to a first bone (12) and a second, ball-holding prosthesis part (13) for attachment to a second bone (14) that intermates

  13. [Results after replacement of femoral neck prostheses - thrust plate prosthesis (TPP) versus ESKA cut prosthesis].

    Science.gov (United States)

    Ishaque, B A; Gils, J; Wienbeck, S; Donle, E; Basad, E; Stürz, H

    2009-01-01

    The aim of this study was to analyse and evaluate comparatively loosening mechanisms, failure frequency, surgical changing strategies and results after replacement of thrust plate prostheses (TPP) and ESKA Cut prostheses. Between 1993 und 2007, 465 TPP and in the years 2000 and 2001 82 ESKA Cut prostheses were performed and evaluated prospectively. Until 2007 46 change interventions of the TPP and 35 of the CUT prosthesis became necessary. All patients who received a stem revision procedure in our hospital were included within this study. Besides the evaluation of clinical results according to the criteria of the Harris Hip Score on the average at 15.6 months (+/- 14.4) postoperatively, radiological loosening processes and surgical difficulties were registered. Furthermore, an analysis of perioperative data was performed according to some criteria of the German Federal Office of Quality Assurance (BQS), such as duration of the surgery, intraoperative blood loss and complications. Statistical investigations for comparative analysis as well as survival analysis of both groups were calculated using SPSS for Windows 13.0. The mean age of the 46 patients who had to undergo revision surgery after TPP was 60.1 years, that of 35 patients in whom revision surgery was necessary after receiving an ESKA Cut femoral neck stem was 56.6 years. The survival rate analysis according to Kaplan-Meier at 13 years was 89.4 % (TPP) and 53.6 % at 66 months (ESKA Cut). In all cases the partial osteointegration of the tripod surface of the loosened Cut prosthesis complicated the explantation. It led on the one hand to a significant difference of the surgery duration and on the other hand to an increased frequency of fractures of the trochanteric region. The conversion of the TPP on standard type stems was usually free of problems. The HHS increased significantly to the averages of 86.6 (TPP) or, respectively, 91.69 (ESKA Cut) after revision. In comparison with the usually problem

  14. Magnetic suspension hip joint: an ideal design of an artificial joint.

    Science.gov (United States)

    Dai, Min; Nie, Tao

    2010-12-01

    Artificial joints present certain problems such as osteal absorption and lysis induced by wear debris which leads to loosening of the prosthesis over a period of time. Here we propose a design of an artificial magnetic suspension joint that was prepared by integrating the medical theories of modern material science, magnetism, and medical physics. According to clinical characteristic of biological and mechanical for hip joint, we designed the appearance and dimensions of magnetic suspension joint and placed neodymium-iron-boron permanent magnets in the prosthesis. As the same time, we performed mechanical and biological experiments using artificial magnetic suspension hip joints models. By simulated the human hip structure and the external load, we discovered the artificial magnetic suspension hip joints models had much lesser amount and size of wear debris than the ceramic/ceramic artificial hip joint prosthesis in friction wear tests. The force between the artificial joints with magnetic materials that we have calculated is feasible for application of artificial joint. The design of artificial magnetic suspension hip joints models was plausible technically and safe biologically. Artificial magnetic suspension hip joints may effectively reduce the incidence of the loosening of prosthesis over a period of time.

  15. [Luxation of the prothesis after total hip arthroplasty].

    Science.gov (United States)

    Białecki, Piotr; Gusta, Andrzej; Bohatyrewicz, Andrzej; Ferenc, Marcin

    2006-01-01

    In this report we evaluated the incidence of complications following the total hip arthroplasty. We have focused on the role of the surgical approach as thepatient cause of the luxation of the prosthesis. Retrospective analysis of 393 endoprosthetic surgeries performed in the Department of Orthopedics and Traumatology, Pomeranian Medical University, between April 2002 and December 2003 was conducted. Out of 9 patients with prosthesis luxation 6 patients were operated using the posterior approach. A comparative analysis of selected groups did not reveal any significant differences in clinical condition of the patient, the implantation technique or the type of the applied prosthesis. We suggest that the main cause of prosthesis luxation were mistakes that led to misaligment of the prosthetic elements, and the posterior approach was believed to be the the predisposing factor.

  16. Hip Pain

    Science.gov (United States)

    ... diagnosis and decision making. In: DeLee & Drez's Orthopaedic Sports Medicine: Principles and Practice. 4th ed. Philadelphia, Pa.: ... http://www.mayoclinic.org/symptoms/hip-pain/basics/definition/SYM-20050684 . Mayo Clinic Footer Legal Conditions and ...

  17. Rose Hip

    Science.gov (United States)

    ... shows that taking rose hip powder mixed with apple juice does not affect weight or blood sugar ... Rose, Phool Gulab, Pink Rose, Poire d'oiseaux, Rosa alba, Rosa canina, Rosa centifolia, Rosa damascena, Rosa ...

  18. Hip ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Martinoli, Carlo, E-mail: carlo.martinoli@libero.it [Radiologia, DISC, Università di Genova, Largo Rosanna Benzi 8, I-16132 Genoa (Italy); Garello, Isabella; Marchetti, Alessandra; Palmieri, Federigo; Altafini, Luisa [Radiologia, DISC, Università di Genova, Largo Rosanna Benzi 8, I-16132 Genoa (Italy); Valle, Maura [Radiologia, Gaslini Children Hospital, Genova (Italy); Tagliafico, Alberto [Radiologia, National Institute for Cancer Research, Genoa (Italy)

    2012-12-15

    In newborns, US has an established role in the detection and management of developmental dysplasia of the hip. Later in childhood, when the limping child is a major diagnostic dilemma, US is extremely helpful in the identification of the varied disease processes underlying this condition, as transient synovitis, septic arthritis, Perthes disease and slipped femoral capital epiphysis. In adolescent practicing sporting activities, US is an excellent means to identify apophyseal injures about the pelvic ring, especially when avulsions are undisplaced and difficult-to-see radiographically. Later on, in the adulthood, US is an effective modality to diagnose tendon and muscle injuries about the hip and pelvis, identify effusion or synovitis within the hip joint or its adjacent bursae and guide the treatment of these findings. The aim of this article is to provide a comprehensive review of the most common pathologic conditions about the hip, in which the contribution of US is relevant for the diagnostic work-up.

  19. Primary extra-cranial meningioma following total hip replacement

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, T.J.; Beggs, I. [Royal Infirmary, Department of Radiology, Edinburgh (United Kingdom); Patton, J.T.; Porter, D. [Royal Infirmary, Department of Orthopaedics, Edinburgh (United Kingdom); Salter, D.M.; Al-Nafussi, A. [Royal Infirmary, Department of Pathology, Edinburgh (United Kingdom)

    2009-01-15

    A 61-year-old man presented with pain at the left hip and decreased mobility 10 years after total hip replacement. Imaging demonstrated a large destructive expansile mass adjacent to the prosthesis. Histological analysis confirmed the presence of an extra-cranial meningioma. Primary tumours after total hip replacement are rare and include soft tissue sarcomas, bone sarcomas and lymphomas. To our knowledge, no previous cases of primary extracranial meningioma have been identified. The imaging features, histology, pathogenesis and differential diagnosis are discussed. (orig.)

  20. Ideal femoral head size in total hip arthroplasty balances stability and volumetric wear.

    Science.gov (United States)

    Cross, Michael B; Nam, Denis; Mayman, David J

    2012-10-01

    Over the last several years, a trend towards increasing femoral head size in total hip arthroplasty to improve stability and impingement free range of motion has been observed. The specific questions we sought to answer in our review were: (1) What are the potential advantages and disadvantages of metal-on-metal, ceramic-on-ceramic, and metal-on-polyethylene bearings? (2) What is effect that femoral head size has on joint kinematics? (3) What is the effect that large femoral heads have on bearing surface wear? A PubMed search and a review of 2012 Orthopaedic Research Society abstracts was performed and articles were chosen that directly answered components of the specific aims and that reported outcomes with contemporary implant designs or materials. A review of the literature suggests that increasing femoral head size decreases the risk of postoperative dislocation and improves impingement free range of motion; however, volumetric wear increases with large femoral heads on polyethylene and increases corrosion of the stem in large metal-on-metal modular total hip arthroplasty (THA); however, the risk of potentially developing osteolysis or adverse reactions to metal debris respectively is still unknown. Further, the effect of large femoral heads with ceramic-on-ceramic THA is unclear, due to limited availability and published data. Surgeons must balance the benefits of larger head size with the increased risk of volumetric wear when determining the appropriate head size for a given patient.

  1. Evaluation of Gait Performance of a Hemipelvectomy Amputation Walking with a Canadian Prosthesis

    Directory of Open Access Journals (Sweden)

    M. T. Karimi

    2014-01-01

    Full Text Available Background. Hemipelvectomy amputation is a surgical procedure in which lower limb and a portion of pelvic are removed. There are a few studies in the literature regarding the performance of subjects with hip disarticulation during walking. However, there is no study on gait analysis of hemipelvectomy subject. Therefore, the aim of this paper was to evaluate the gait and stability of subject with hemipelvectomy amputation. Case Description and Methods. A subject with hemipelvectomy amputation at right side was involved in this study. He used a Canadian prosthesis with single axis ankle joint, 3R21 knee joint, and 7E7 hip joint for more than 10 years. The kinetic and kinematic parameters were collected by a motion analysis system and a Kistler force platform. Findings and Outcomes. There was a significant difference between knee, hip, and ankle range of motions and their moments in the sound and prosthesis sides. In the other side, the stability of the subject in the anteroposterior direction seems to be better than that in the mediolateral direction. Conclusions. There was a significant asymmetry between the kinetic and kinematic performance of the sound and prosthesis sides, which may be due to lack of muscular power and alignment of prosthesis components.

  2. Prosthesis-patient mismatch

    Directory of Open Access Journals (Sweden)

    Philippe Pibarot

    2011-04-01

    Full Text Available Prosthesis-patient mismatch (PPM is present when the effective orifice area of the inserted prosthetic valve is too small in relation to body size. Its main hemodynamic consequence is to generate higher than expected gradients through normally functioning prosthetic valves. The purpose of this review is to present an update on the present state of knowledge with regards to diagnosis, prognosis and prevention of PPM. PPM is a frequent occurrence (20%–70% of aortic valve replacements that has been shown to be associated with worse hemodynamics, less regression of left ventricular hypertrophy, more cardiac events, and lower survival. Moreover, as opposed to most other risk factors, PPM can largely be prevented by using a prospective strategy at the time of operation.

  3. Bioelectronic retinal prosthesis

    Science.gov (United States)

    Weiland, James D.

    2016-05-01

    Retinal prosthesis have been translated to clinical use over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa and one device is in clinical trials for treatment of age-related macular degeneration. These devices provide partial sight restoration and patients use this improved vision in their everyday lives to navigate and to detect large objects. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. In particular, current retinal prostheses do not provide peripheral visions due to technical and surgical limitations, thus limiting the effectiveness of the treatment. This paper reviews recent results from human implant patients and presents technical approaches for peripheral vision.

  4. Histologic analysis of a retrieved hydroxyapatite-coated femoral prosthesis

    DEFF Research Database (Denmark)

    Søballe, K; Gotfredsen, K; Brockstedt-Rasmussen, H

    1991-01-01

    A hydroxyapatite-coated hip hemi-prosthesis was retrieved from a 98-year-old osteoporotic woman 12 weeks after implantation. Histologic analysis revealed bone and fibrous tissue almost evenly distributed around the surface of the implant circumference. Quantitative histologic analysis showed...... that 48% of the hydroxyapatite surface was covered by bone. Fibrous tissue covered 30% of the prosthetic surface, and 20% of the surface had no tissue coverage. Scanning electron microscopy showed direct contact without any clear boundary between the newly formed bone and the hydroxyapatite ceramic....

  5. Comparison of two different rehabilitation programmes for thrust plate prosthesis: a randomized controlled study.

    Science.gov (United States)

    Unver, Bayram; Karatosun, Vasfi; Gunal, Izge; Angin, Salih

    2004-02-01

    Weight bearing after total hip arthroplasty is postponed in order to prevent early loosening, but this negatively affects the rehabilitation programme. For the force transfer characteristics of thrust plate prosthesis (TPP), a new type of hip prosthesis used without cement is similar to the normal hip. We evaluated the possibilities of early weight bearing after TPP by comparing early partial with early full weight bearing. Randomized controlled study. Department of orthopaedics and traumatology in a university hospital. Sixty hips of 51 patients who underwent total hip arthroplasty with TPP were randomly assigned into two groups. Both groups received accelerated rehabilitation programmes: group 1 with early partial weight bearing and group 2 with early full weight bearing. Patients were evaluated by a blind observer preoperatively, at three months after surgery by clinical (measurement of range of hip motion (universal goniometry), muscle strength (Manual Muscle Test), functional test (6-minute walk test), hip function (Harris Hip Scoring System)) and radiographical parameters and one year after surgery by clinical (Harris Hip Scoring System) and radiographical parameters. Group 2 performed transfer activities earlier, had more walking distance at the time of discharge and shorter hospital stay than group 1. At three months, Harris Hip Score, muscle strength, 6-minute walk test, and duration of crutch use were significantly (p < 0.05) in favour of group 2. None of the patients in either group showed signs of loosening one year after the operation. These results suggest that patients with TPP can tolerate an accelerated rehabilitation programme with early weight bearing and will gain the goals of rehabilitation earlier.

  6. Photovoltaic retinal prosthesis

    Science.gov (United States)

    Loudin, James; Mathieson, Keith; Kamins, Ted; Wang, Lele; Galambos, Ludwig; Huie, Philip; Sher, Alexander; Harris, James; Palanker, Daniel

    2011-03-01

    Electronic retinal prostheses seek to restore sight to patients suffering from retinal degenerative disorders. Implanted electrode arrays apply patterned electrical stimulation to surviving retinal neurons, producing visual sensations. All current designs employ inductively coupled coils to transmit power and/or data to the implant. We present here the design and initial testing of a photovoltaic retinal prosthesis fabricated with a pixel density of up to 177 pixels/mm2. Photodiodes within each pixel of the subretinal array directly convert light to stimulation current, avoiding the use of bulky coil implants, decoding electronics, and wiring, and thereby reducing surgical complexity. A goggles-mounted camera captures the visual scene and transmits the data stream to a pocket processor. The resulting images are projected into the eyes by video goggles using pulsed, near infrared (~900 nm) light. Prostheses with three pixel densities (15, 55, and 177 pix/mm2) are being fabricated, and tests indicate a charge injection limit of 1.62 mC/cm2 at 25Hz. In vitro tests of the photovoltaic retinal stimulation using a 512-element microelectrode array have recorded stimulated spikes from the ganglion cells, with latencies in the 1-100ms range, and with peak irradiance stimulation thresholds varying from 0.1 to 1 mW/mm2. With 1ms pulses at 25Hz the average irradiance is more than 100 times below the IR retinal safety limit. Elicited retinal response disappeared upon the addition of synaptic blockers, indicating that the inner retina is stimulated rather than the ganglion cells directly, and raising hopes that the prosthesis will preserve some of the retina's natural signal processing.

  7. Comparison of radiographic and radionuclide hip arthrography in determination of femoral component loosening of hip arthroplasties

    International Nuclear Information System (INIS)

    Capello, W.N.; Uri, B.G.; Wellman, H.N.; Robb, J.A.; Stiver, P.L.

    1985-01-01

    Radiographic examination of a patient experiencing pain following total hip arthroplasty is an important step in the systematic approach to evaluating component loosening, even though the information yielded is often equivocal and nondiagnostic in assessing component loosening. The radiographic criteria for loosening are especially difficult to assess following revision surgery, for radiolucent lines frequently exist at the bone-cement interface immediately following implantation. The advent of noncemented hip prostheses poses another problem: the routinely noted disruption of bone-cement of prosthesis-cement interfaces is not present with uncemented prostheses. As the criteria for loosening of the noncemented prostheses are still evolving, plain radiographic examination is frequently nondiagnostic. Femoral component loosening is difficult to detect with standard contrast arthrography because the bone, metal, surrounding radiopaque cement and contrast agents have similar or identical radiographic appearances. In contrast arthrography, if the prosthesis is loose the injected agent opacifies the radiolucent zone encircling the prosthesis or cement mangle. Because of the similarity in the appearances of these agents and the surrounding structures on x-ray films, interpretation is difficult. The inclusion of subtraction techniques in routine contrast arthrography has improved its accuracy; however, these techniques require special equipment and demand precise patient positioning. The purpose of this study is to introduce a new form of hip arthrography using a radionuclide agent in place of the contrast agent. A comparison of the results using these two techniques is presented

  8. [Bone-anchored auricular prosthesis].

    Science.gov (United States)

    Bille, M; Homøe, P; Vesterhauge, S; Rixen, M; Bretlau, P

    1994-10-03

    During the period February 1989-September 1991, 15 patients with absent or defective pinna were treated with a bone-anchored auricular prosthesis at the ENT-department, Rigshospitalet, Copenhagen. These patients were followed up from the hospital records and by means of a questionnaire. Altogether 40 titanium implants have been inserted, of which one implant was found not to be integrated at the time of the second-stage surgery. Five patients underwent additional surgery, one patient because of non-integration of a screw, and four patients on account of soft-tissue reactions. From the questionnaire replies it appears that all patients found the cosmetic result and the technique concerning mounting of the prosthesis very satisfactory. Nearly half the patients found that the care of the skin around the abutments caused considerable problems. Three patients had experienced unintended losses of the prosthesis. In conclusion, treatment with a bone anchored auricular prosthesis has considerable advantages compared to treatment with a prosthesis attached by adhesive. Furthermore the use of a bone-anchored prosthesis should be considered a viable alternative to surgical reconstruction because of the outstanding aesthetic result and because the surgical procedure puts less strain on the patient. The disadvantage of the method is the lifelong daily care of the skin and the dependence on the health services.

  9. Diagnosis of infection after total hip arthroplasty

    International Nuclear Information System (INIS)

    Itasaka, Toshio; Kawai, Akira; Sato, Toru; Mitani, Shigeru; Inoue, Hajime

    2001-01-01

    Forty-eight total hip arthroplasties for which revision surgery was performed were reviewed to determine the accuracy of laboratory tests, plain radiographs, hip aspiration, and technetium-99m MDP and gallium-67 scans in demonstrating the presence or absence of infection of the prosthesis. Six of the 48 hips were diagnosed as having an infection at the revision surgery. The erythrocyte sedimentation rate and the C-reactive protein levels were significantly higher in the patients with infected prostheses. The difference in the white blood cell count was not significant. There was no significant relationship between the presence of infection and the severity of loosening and instability of the implants diagnosed by plain radiographs. The accuracy of hip aspiration in diagnosing the infection was 83%, with a sensitivity of 40% and a specificity of 92%. The accuracy of technetium-99m MDP bone scan was 79%, with a sensitivity of 83%, and a specificity of 79%. Gallium-67 scan had an accuracy of 96%, a sensitivity of 67%, and a specificity of 100%. The findings in the present study indicated that diagnostic tests consisting of laboratory tests and plain radiography, followed by hip aspiration and sequential use of technetium-99m MDP and gallium-67 scintigraphies, are suitable for differentiation between mechanical loosening and infection of total hip arthroplasty. (author)

  10. Diagnosis of infection after total hip arthroplasty

    Energy Technology Data Exchange (ETDEWEB)

    Itasaka, Toshio; Kawai, Akira; Sato, Toru; Mitani, Shigeru; Inoue, Hajime [Okayama Univ. (Japan). School of Medicine

    2001-07-01

    Forty-eight total hip arthroplasties for which revision surgery was performed were reviewed to determine the accuracy of laboratory tests, plain radiographs, hip aspiration, and technetium-99m MDP and gallium-67 scans in demonstrating the presence or absence of infection of the prosthesis. Six of the 48 hips were diagnosed as having an infection at the revision surgery. The erythrocyte sedimentation rate and the C-reactive protein levels were significantly higher in the patients with infected prostheses. The difference in the white blood cell count was not significant. There was no significant relationship between the presence of infection and the severity of loosening and instability of the implants diagnosed by plain radiographs. The accuracy of hip aspiration in diagnosing the infection was 83%, with a sensitivity of 40% and a specificity of 92%. The accuracy of technetium-99m MDP bone scan was 79%, with a sensitivity of 83%, and a specificity of 79%. Gallium-67 scan had an accuracy of 96%, a sensitivity of 67%, and a specificity of 100%. The findings in the present study indicated that diagnostic tests consisting of laboratory tests and plain radiography, followed by hip aspiration and sequential use of technetium-99m MDP and gallium-67 scintigraphies, are suitable for differentiation between mechanical loosening and infection of total hip arthroplasty. (author)

  11. Hip Problems in Infants

    Science.gov (United States)

    ... A hip problem in infants is known as developmental dysplasia of the hip (DDH). It is when the ball of the ... later in life? Resources International Hip Dysplasia Institute, Developmental Dysplasia of the Hip (DDH) International Hip Dysplasia Institute, Hip-Healthy Swaddling ...

  12. The new spongiosa-hip-joint-endoprosthesis (SHEP).

    Science.gov (United States)

    Täger, K H

    1993-01-01

    The new endoprosthesis system SHEP (Spongiosa Hip Endo-Prosthesis) developed by the author and manufactured by Howmedica has been in clinical use since October 1987. This system comprises a hollow-stem prosthesis with a microporous surface and a straight, collarless stem with circular and oval perforations in the anterior and posterior surfaces. The conical threaded acetabular component is doublewalled. In primary operations endogenous spongiosa is packed into the spaces in the acetabulum and the cavity of the stem, and in exchange procedures the spaces are packed with homologous spongiosa preserved under cold storage. The prosthetic components are implanted cement-free. The system is indicated in all forms of osteoarthritis of the hip. To date more than 360 SHEPs have been implanted by the author and at other clinics, 1/3 of which were exchange prostheses. The biomechanical properties of the prosthesis have undergone endurance tests and far exceed the statutory values. The SHEP system is made of Vitallium, the inlay is polyethylene, and the head is ceramic. Scintiscans initially show raised counting rate quotients compared with the healthy side. Video film reveals impressive bony regeneration and peg-shaped bony bridges between the inner cortical bone and the prosthesis. Microscopic examination shows lamellar bone, rich in osteocytes and osteoblasts. Microscopic investigation of samples from inside the prosthesis (after 5, 9 and 12 months) shows transformation of foreign spongiosa and substitution by endogenous spongiosa or spongy bone with lamellar stratification and good microvascularization.

  13. A Hip Implant Energy Harvester

    Science.gov (United States)

    Pancharoen, K.; Zhu, D.; Beeby, S. P.

    2014-11-01

    This paper presents a kinetic energy harvester designed to be embedded in a hip implant which aims to operate at a low frequency associated with body motion of patients. The prototype is designed based on the constrained volume available in a hip prosthesis and the challenge is to harvest energy from low frequency movements (< 1 Hz) which is an average frequency during free walking of a patient. The concept of magnetic-force-driven energy harvesting is applied to this prototype considering the hip movements during routine activities of patients. The magnetic field within the harvester was simulated using COMSOL. The simulated resonant frequency was around 30 Hz and the voltage induced in a coil was predicted to be 47.8 mV. A prototype of the energy harvester was fabricated and tested. A maximum open circuit voltage of 39.43 mV was obtained and the resonant frequency of 28 Hz was observed. Moreover, the power output of 0.96 μW was achieved with an optimum resistive load of 250Ω.

  14. [The total shoulder prosthesis].

    Science.gov (United States)

    Mazas, F; Gagey, O

    1990-04-11

    Prosthetic shoulder replacement is impeded by two main obstacles: the articular cavity is very shallow, and the small glenoid surface rests on a narrow neck to which prosthetic pieces are difficult to attach. The principal, currently used prostheses are non-retentive models which reproduce the anatomy of the joint. They differ from each other mainly in the glenoid piece pattern which may be sealed only to the glenoid cavity or also fixed onto the acromion. On the whole, the clinical results reported are encouraging, particularly as regards the absence of pain, but the radiological course of the glenoidal sealing is a source of concern. Obvious unsealing is rare, but cracks between bone and cement are very frequent and some of them become wider as time goes by. In addition, there is still no satisfactory solution to the problem of big rotator cuff tears. This type of prosthesis must be envisaged with caution and should be reserved to very painful shoulders, but it would be wise not to wait until the rotator cuff is destroyed. The best indications are glenohumeral osteoarthritis, rheumatoid arthritis and necrosis of the tumoral head.

  15. [Hip fractures].

    Science.gov (United States)

    Weisová, Drahomíra; Salášek, Martin; Pavelka, Tomáš

    2013-01-01

    Hip fractures are ranked among the frequent injuries. These fractures have been often coupled with high energy trauma in children and in patients with normal bone structure, low energy trauma and osteoporotic fracture (fragility fracture) is typical in elder patients. Hip fractures are divided into five groups: femoral head fracture, femoral neck fracture, pertrochanteric, intertrochateric and subtrochanteric fracture. Surgical treatment is indicated in all patients unless contraindications are present. Long bed rest has been accompanied by a high risk of development of thromboembolic disease, pneumonia and bed sore. Healing in the wrong position and nonunions are often the result of conservative treatment. Screw osteosynthesis is performed in isolated femoral head factures. Three cannulated screws or a DHS plate (dynamic hip screw) are used in fractures of the femoral neck with normal femoral head perfusion, total hip replacement is recommended in elder patients and in case of loss of blood supply of the femoral head. Pertrochanteric and intertrochanteric fractures can be stabilized by the femoral nails (PFN, PFN A, PFH - proximal femoral nail), nails are suitable for minimally invasive insertion and provide higher stability in the shaft, or plates (DHS) designed for stable pertronchanteric and intertrochanteric fractures. Subtrochanteric fractures can be fixed also intramedullary (nails - PFN long, PFN A long) and extramedullary (plates - DCS dynamic condylar screw, proximal femoral LCP - locking compression plate). Open reduction with internal plate fixation is advantageous for pathological fractures, as biopsy sampling can be performed. Hip fracture rehabilitation is integral part of the treatment, including walking on crutches or with a walker with partial weight bearing for at least six weeks.

  16. Stress shielding effects of two prosthetic groups after total hip joint simulation replacement.

    Science.gov (United States)

    Piao, Chengdong; Wu, Dankai; Luo, Min; Ma, Hongshun

    2014-08-30

    The study aims to compare the stress shielding effects of implantable anatomical and traditional prostheses after in vitro total hip joint replacement simulation. The study serves as a biomechanical basis for novel artificial prostheses and for clinical hip joint replacements. Sixteen femoral specimens from adult male corpses were randomly divided into two groups: the traditional prosthesis group implanted into femur specimens using simulated total hip joint replacement (n = 8) and the femoral neck-preserved anatomical prosthesis implantation group that used a collum femoris preserving stem/trabeculae oriented pattern (CFP/TOP) acetabular cup (n = 8). The strain values in the two groups before and after prosthesis implantation were measured at different test points using electric resistance strain gauges. The stress shielding rate was calculated according to the related formula. The results showed that the rates of proximal femoral stress shielding were significantly higher at test points 1-10 in the traditional femoral prosthesis transplantation group than in the anatomical prosthesis group (p prosthesis implants.

  17. [Endourethral prosthesis. Current indications, materials and types of prosthesis].

    Science.gov (United States)

    Paterlini, Juan Esteban

    2014-01-01

    To update the topic of endourethral prosthesis for the treatment of recurrent urethral stenosis comprehensively, focusing on current indications, materials and types of prosthesis in use nowadays. We used the PubMed database (1995-2013) with the terms "endourethral ", "prostheses","endourethral prosthesis "and selected the most relevant articles for this publication. Results were variable depending on the series published, with great differences among them. They are not homogeneous groups, so they are not comparable to each other. Endourethral prostheses have an important role today in the treatment of recurrent urethral stenosis. More studies are required, with longer follow up to be able to establish which one is the one with the lowest complication rates and best results in terms of urethral caliber and symptom questionnaire.

  18. Investigation of creep mechanical characteristics of femoral prostheses by simulated hip replacement

    Science.gov (United States)

    LIU, GUANG-YAO; JIN, YAN; LI, PENG

    2013-01-01

    In order to provide creep mechanical parameters for the clinical application of both traditional and reserved anatomy femoral artificial joint replacements, simulated hip replacement femoral stress relaxation and creep experiments were performed. Twenty-four corpse femoral specimens were obtained, with 8 specimens being randomly assigned to the control group and 8 specimens being randomly assigned to the traditional prosthesis group. Our results showed that the retaining femoral neck prosthesis and traditional prosthesis groups have different stress relaxation and creep mechanical properties. PMID:23596489

  19. An experimental-numerical method for comparative analysis of joint prosthesis

    International Nuclear Information System (INIS)

    Claramunt, R.; Rincon, E.; Zubizarreta, V.; Ros, A.

    2001-01-01

    The difficulty that exists in the analysis of mechanical stresses in bones is high due to its complex mechanical and morphological characteristics. This complexity makes generalists modelling and conclusions derived from prototype tests very questionable. In this article a relatively simple comparative analysis systematic method that allow us to establish some behaviour differences in different kind of prosthesis is presented. The method, applicable in principle to any joint problem, is based on analysing perturbations produced in natural stress states of a bone after insertion of a joint prosthesis and combines numerical analysis using a 3-D finite element model and experimental studies based on photoelastic coating and electric extensometry. The experimental method is applied to compare two total hip prosthesis cement-free femoral stems of different philosophy. One anatomic of new generation, being of oblique setting over cancellous bone and the other madreporique of trochantero-diaphyseal support over cortical bone. (Author) 4 refs

  20. EXPERIMENTAL RESEARCH OF REGENERATIVE FEATURES IN BONE TISSUES AROUND IMPLANTS AFTER ONE-STAGE BILATERAL TOTAL HIP REPLACEMENT

    Directory of Open Access Journals (Sweden)

    V. M. Mashkov

    2012-01-01

    Full Text Available Objective: to research the specific features of regenerative processes of bone tissue around implants after one-stage bilateral total hip replacement in experiment. Material and methods: 27 total hip replacement operations have been performed in 18 rabbits of breed "chinchilla" to which bipolar femoral endoprosthesis made of titanic alloy PT-38, one type-size, with friction pair metal-on-metal and neck-shaft angle 165 degrees have been implanted: total unilateral hip replacement operations have been performed in 9 animals (control group, one-stage bilateral total hip replacement operations have been performed in 9 animals (experimental group. During research they have been on radiological and clinical checking-up. After the experiment the animals had histological tests of the tissues around endoprosthesis components. Results and conclusions: After one-stage bilateral total hip replacement in early terms of research more expressed changes of bone tissue in the form of its thinning and decompaction were found around implants. One-stage bilateral total hip replacement did not essentially influence on the speed of osteogenesis around endoprothesis components in comparison with unilateral total hip replacement, so in late terms of observation in both groups the fixing of endoprothesis components did not differ.

  1. Prosthetic Rehabilitation After Hip Disarticulation or Hemipelvectomy.

    Science.gov (United States)

    Kralovec, Michael E; Houdek, Matthew T; Andrews, Karen L; Shives, Thomas C; Rose, Peter S; Sim, Franklin H

    2015-12-01

    Prosthetic rehabilitation after pelvic-level amputation (hemipelvectomy/hip disarticulation) is difficult, and because of this, many patients are never fit with a prosthetic limb. The objectives of the study were to evaluate the characteristics of successful prosthetic users and to determine what factors are associated with successful prosthetic fitting and use. The authors identified 43 patients who underwent hip disarticulation/hemipelvectomy between 2000 and 2010 and were candidates for prosthetic fitting at the authors' institution. The medical records of these patients were then reviewed for pertinent demographic and medical characteristics to identify the profile of successful prosthetic users. Of 43 patients, 18 (43%) successfully used a prosthetic limb. The only preoperative factor associated with unsuccessful prosthetic fitting was coronary artery disease. Specifically, age, body mass index, other medical comorbidities, and demographic characteristics were not associated with successful or unsuccessful prosthetic fitting. Successful users wore their prosthesis an average of 5.8 hrs/day, and most ambulated with one or both hands free. Successful prosthetic rehabilitation after hemipelvectomy and hip disarticulation is possible. Increased body mass index, advanced age, depression, and other comorbidities should not discourage prosthetic rehabilitation. Most patients that undergo prosthetic rehabilitation enjoy long periods of survival and wear their prosthesis for most of the day.

  2. Metallic ion release after knee prosthesis implantation: a prospective study.

    Science.gov (United States)

    Lons, Adrien; Putman, Sophie; Pasquier, Gilles; Migaud, Henri; Drumez, Elodie; Girard, Julien

    2017-12-01

    Metal-on-metal (MoM) hip replacement bearings produce metallic ions that can cause health complications. Metallic release also occurs with other materials, but data on metallic ion levels after knee arthroplasty are sparse. We postulate that knee replacement generates elevating metallic ions (chromium (Cr), cobalt (Co) and titanium (Ti)) during the first year after implantation. This ongoing prospective study included all patients who underwent the same type of knee arthroplasty between May and December 2013. Cr, Co and Ti levels were measured in whole blood at pre-operation and one-year follow-up (6 and 12 months). Clinical and radiographic data (range of motion, Oxford, International Knee Society (IKS) and satisfaction scores) were recorded. In 90 patients, preoperative Cr, Co and Ti metallic ion levels were respectively 0.45 μg/l, 0.22 μg/l, 2.94 μg/l and increased to 1.27 μg/l, 1.41 μg/l, 4.08 μg/l (p < 0.0001) at last one-year follow-up. Mean Oxford and IKS scores rose, respectively, from 45.9 (30-58) and 24.9 (12-52) to 88.3 (0-168) and 160.8 (93-200) (p < 0.001). After the implantation of knee arthroplasty, we found significant blood elevation of Cr, Co and Ti levels one year after implantation exceeding the normal values. This metallic ion release could lead to numerous effects: allergy, hypersensitivity, etc.

  3. 21 CFR 878.3590 - Ear prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and... GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An ear prosthesis is a silicone rubber solid device intended to be implanted to reconstruct the external...

  4. 21 CFR 878.3720 - Tracheal prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tracheal prosthesis. 878.3720 Section 878.3720...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3720 Tracheal prosthesis. (a) Identification. The tracheal prosthesis is a rigid, flexible, or expandable tubular device made of a silicone...

  5. 21 CFR 876.3750 - Testicular prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Testicular prosthesis. 876.3750 Section 876.3750...) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Prosthetic Devices § 876.3750 Testicular prosthesis. (a) Identification. A testicular prosthesis is an implanted device that consists of a solid or gel-filled silicone...

  6. 21 CFR 878.3550 - Chin prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Chin prosthesis. 878.3550 Section 878.3550 Food... DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3550 Chin prosthesis. (a) Identification. A chin prosthesis is a silicone rubber solid device intended to be implanted to augment or...

  7. 21 CFR 878.3610 - Esophageal prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Esophageal prosthesis. 878.3610 Section 878.3610...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3610 Esophageal prosthesis. (a) Identification. An esophageal prosthesis is a rigid, flexible, or expandable tubular device made...

  8. 21 CFR 878.3680 - Nose prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nose prosthesis. 878.3680 Section 878.3680 Food... DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3680 Nose prosthesis. (a) Identification. A nose prosthesis is a silicone rubber solid device intended to be implanted to augment or...

  9. Prospective study comparing functional outcomes and revision rates between hip resurfacing and total hip arthroplasty: preliminary results for 2 years

    Directory of Open Access Journals (Sweden)

    Régis Pailhé

    2013-07-01

    Full Text Available There is a need of independent prospective studies about modern generation of hip resurfacing implants. The aim of this propective observational study was to compare the functional outcomes and revision rates with hip resurfacing arthroplasty and total hip arthroplasty and to present the preliminary results at 2 years. Patients included were recruited prospectively in the Partial Pelvic Replacement Hip Project by a single surgeon between January 2007 and January 2010. Patients were assessed with the Harris Hip Score (HHS and Postel-Merle d’Aubigné (MDA score and Devane Score. The end point of the study was reoperation for any cause related to the prosthesis. At a mean follow up of 38.6 months there were a total of 142 patients with hip resurfacing (group 1 [100 Durom® (Zimmer Inc., Warsaw, IN, USA and 42 Birmingham Hip Resurfacing® (Smith & Nephew, Memphis, TN, USA] and 278 patients with total hip arthroplasty (group 2. The results showed significantly greater gain of HHS, MDA and Devane score with hip resurfacing procedures. However, considering all the complications, the rate was significantly higher in group 16.4% vs 1.79% in group 2 (P<0.0001. In group 1 we observed 6 complications only concerned males with Durom® implants. The follow up of this cohort is still on going and may deliver more information on the evolution of these results in time.

  10. Systemic cobalt toxicity from total hip arthroplasties: review of a rare condition Part 2. measurement, risk factors, and step-wise approach to treatment.

    Science.gov (United States)

    Zywiel, M G; Cherian, J J; Banerjee, S; Cheung, A C; Wong, F; Butany, J; Gilbert, C; Overgaard, C; Syed, K; Jacobs, J J; Mont, M A

    2016-01-01

    As adverse events related to metal on metal hip arthroplasty have been better understood, there has been increased interest in toxicity related to the high circulating levels of cobalt ions. However, distinguishing true toxicity from benign elevations in cobalt levels can be challenging. The purpose of this review is to examine the use of cobalt alloys in total hip arthroplasty, to review the methods of measuring circulating cobalt levels, to define a level of cobalt which is considered pathological and to review the pathophysiology, risk factors and treatment of cobalt toxicity. To the best of our knowledge, there are 18 published cases where cobalt metal ion toxicity has been attributed to the use of cobalt-chromium alloys in hip arthroplasty. Of these cases, the great majority reported systemic toxic reactions at serum cobalt levels more than 100 μg/L. This review highlights some of the clinical features of cobalt toxicity, with the goal that early awareness may decrease the risk factors for the development of cobalt toxicity and/or reduce its severity. Severe adverse events can arise from the release of cobalt from metal-on-metal arthroplasties, and as such, orthopaedic surgeons should not only be aware of the presenting problems, but also have the knowledge to treat appropriately. ©2016 The British Editorial Society of Bone & Joint Surgery.

  11. Edge loading has a paradoxical effect on wear in metal-on-polyethylene total hip arthroplasties.

    Science.gov (United States)

    Harris, William H

    2012-11-01

    Edge wear is an adverse factor that can negatively impact certain THAs. In some metal-on-metal THAs, it can lead to adverse tissue reactions including aseptic lymphocytic vasculitis-associated lesions and even to pseudotumor formation. In some ceramic-on-ceramic THAs, it can lead to squeaking and/or stripe wear. Edge wear in metal-on-metal and ceramic-on-ceramic THAs can also be associated with accelerated wear across the articulation of these joints. I asked: Does edge wear occur in metal-on-polyethylene (MOP) articulations? And if so, does it increase joint wear? I examined the evidence in the literature for edge wear occurring in MOP THA and then assessed the evidence in the literature for data supporting the concept that edge wear in MOP hips could accelerate wear across the articulation over time. Extensive data in the literature confirm edge wear is common in MOP THA. Surprisingly, the evidence does not support that it accelerates wear across the articulation. In fact, substantial data support the concept that it does not. These observations suggest, in terms of edge wear accelerating overall wear, MOP articulation may have a privileged position compared to hard-on-hard THA articulations.

  12. Magnetically retained silicone facial prosthesis

    African Journals Online (AJOL)

    2013-06-09

    Jun 9, 2013 ... conditions (ultraviolet light, air pollution, temperature), fragile margins, microbial growth on the open pores of the elastomers leading to rapid degradation of color dexterity. The cheek silicone prosthesis although constructed to the patient's esthetic requirement retaining the same on the face is complicated.

  13. Knee joint replacement prosthesis (image)

    Science.gov (United States)

    A prosthesis is a device designed to replace a missing part of the body, or to make a part of the body work better. The metal prosthetic device in knee joint replacement surgery replaces cartilage and bone which is damaged from disease or aging.

  14. [Unilateral forearm agenesis and prosthesis].

    Science.gov (United States)

    Choumon, B; Ritz, A; Corbet, E; Gréco, J; Bérard, C

    2002-04-01

    Antebrachial agenesis is a congenital deformity which is not invalidating for the children who have a level of independence comparable to that of other children of the same age. Although the appropriateness of a prosthesis is rarely questioned by healthcarers, it is clear that it is the healthcarers' own representation of this condition (their knowledge of the deformity and of the prosthesis proposed) that leads to the indication. The purpose of this study was to better understand the respective representations of unilateral antebrachial agenesis to help determine appropriate health care proposals. An intensive survey using semi-directive interviews was conducted in 16 families. Group interviews with three healthcare teams were then conducted. Three leading topics appeared: worry about the social integration of the child, a paradoxical representation of the child perceived as independent but handicapped, and a largely negative image of the prosthesis. There was a rather important difference in the representations formulated by the parents and by the healthcarers. The discussion focused on awareness of the narcissistic content of the expectations and the plastic and functional implications of prosthesis fitting, perceived differently by parents and healthcarers. The nature of the expected result involves a change in the representation of the child more than a change in the child's body, a concept which in itself is not a true objective of healthcare. Taken the understandably difficult position of healthcarers, it might be useful to propose a different scheme for the first consultation.

  15. Long-term results with the uncemented thrust plate prosthesis (TPP).

    Science.gov (United States)

    Huggler, A H; Jacob, H A; Bereiter, H; Haferkorn, M; Ryf, C; Schenk, R

    1993-01-01

    The long-term clinical results of a novel concept for total joint replacement called the Thrust Plate Prosthesis (TPP) are presented. Only a restricted number of patients were provided with this new prosthesis (115 at the Orthopedic Department, Canton Hospital, Chur, and 47 at the Department of Orthopedic Surgery, University of Zurich). All patients have undergone clinical and radiological follow-up covering a period from 1980 to 1991. The basic feature of the Thrust Plate Prosthesis is the direct load transfer to the medial cortical bone of the femoral neck, and this has been unchanged since 1978. Titanium alloy has been used since 1986. The good clinical and radiological results are confirmed by a histological examination of an 8-year-old implant: In the crucial area of load transfer newly formed bone can be seen in direct contact with the thrust plate without fibrous tissue in between. The clinical results and histological findings have confirmed the validity of the biomechanical principle of the TPP. The TPP is therefore to be considered a true alternative to the conventional hip prosthesis. In contrast to the conventional intramedullary anchored stem prosthesis the TPP requires the removal of a minimum amount of bone stock, which is certainly important in young patients.

  16. Hip Replacement Surgery

    Science.gov (United States)

    ... Initiative Breadcrumb Home Health Topics English Español Hip Replacement Surgery Basics In-Depth Download Download EPUB Download ... What is it? Points To Remember About Hip Replacement Surgery Hip replacement surgery removes damaged or diseased ...

  17. Hip replacement - discharge

    Science.gov (United States)

    ... discharge; Total hip replacement - discharge; Hip hemiarthroplasty - discharge; Osteoarthritis - hip replacement discharge ... such as downhill skiing or contact sports like football and soccer. But you should be able to ...

  18. Hip fracture - discharge

    Science.gov (United States)

    ... Philadelphia, PA: Elsevier; 2017:chap 55. Read More Broken bone Hip fracture surgery Hip pain Leg MRI scan Osteoporosis - overview Patient Instructions Getting your home ready - knee or hip surgery Osteomyelitis - discharge Review ...

  19. Choice of implant combinations in total hip replacement: systematic review and network meta-analysis.

    Science.gov (United States)

    López-López, José A; Humphriss, Rachel L; Beswick, Andrew D; Thom, Howard H Z; Hunt, Linda P; Burston, Amanda; Fawsitt, Christopher G; Hollingworth, William; Higgins, Julian P T; Welton, Nicky J; Blom, Ashley W; Marques, Elsa M R

    2017-11-02

    Objective  To compare the survival of different implant combinations for primary total hip replacement (THR). Design  Systematic review and network meta-analysis. Data sources  Medline, Embase, The Cochrane Library, ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, and the EU Clinical Trials Register. Review methods  Published randomised controlled trials comparing different implant combinations. Implant combinations were defined by bearing surface materials (metal-on-polyethylene, ceramic-on-polyethylene, ceramic-on-ceramic, or metal-on-metal), head size (large ≥36 mm or small meta-analysis for revision. There was no evidence that the risk of revision surgery was reduced by other implant combinations compared with the reference implant combination. Although estimates are imprecise, metal-on-metal, small head, cemented implants (hazard ratio 4.4, 95% credible interval 1.6 to 16.6) and resurfacing (12.1, 2.1 to 120.3) increase the risk of revision at 0-2 years after primary THR compared with the reference implant combination. Similar results were observed for the 2-10 years period. 31 studies (2888 patients) were included in the analysis of Harris hip score. No implant combination had a better score than the reference implant combination. Conclusions  Newer implant combinations were not found to be better than the reference implant combination (metal-on-polyethylene (not highly cross linked), small head, cemented) in terms of risk of revision surgery or Harris hip score. Metal-on-metal, small head, cemented implants and resurfacing increased the risk of revision surgery compared with the reference implant combination. The results were consistent with observational evidence and were replicated in sensitivity analysis but were limited by poor reporting across studies. Systematic review registration  PROSPERO CRD42015019435. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence

  20. Assessment of total hip arthroplasty as a predisposing factor for ischiofemoral impingement

    International Nuclear Information System (INIS)

    Oliveira, Adriana L.; Azevedo, Debora C.; Eajazi, Alireza; Palmer, William E.; Bredella, Miriam A.; Kwon, Young-Min; Torriani, Martin

    2015-01-01

    To examine the effect of total hip arthroplasty (THA) on ischiofemoral (IF) and quadratus femoris (QF) spaces with the hypothesis that THA does not affect ischiofemoral relationships. The study was IRB approved and complied with HIPAA guidelines. We identified consecutive MR examinations (pelvis and/or hip) obtained at our institution in adults (≥18 years old) screened for THA-related complications. Native hips from the same individuals served as controls. We collected medical record data including age, gender, surgical history, and THA designs. Two radiologists independently measured the IF-RAD and IF-MRI (IF space on radiographs and MR imaging, respectively) and QF space (on MR imaging). Groups were compared using ANCOVA controlled for gender. The study group comprised 250 hips (132 subjects; 162 post-THA and 88 native hips). Subjects were aged 59 ± 10 years, with 66 males and 66 females. Comparison of IF-MRI and QF spaces between native and post-THA hips showed no differences (P > 0.12) and IF-RAD was higher in post-THA subjects (P = 0.01). No differences in the IF-MRI and QF spaces were present between native hips and different THA designs (P > 0.4). IF-RAD of metal-on-metal THA was higher than that of native hips (P = 0.01) and trended higher than ceramic-on-polyethylene THA (P = 0.08), with the remaining comparisons showing no significant differences (P > 0.4). Radiographic- and MRI-based measures in patients with standard THA do not show narrowing of IF and QF spaces. (orig.)

  1. Assessment of total hip arthroplasty as a predisposing factor for ischiofemoral impingement

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Adriana L.; Azevedo, Debora C.; Eajazi, Alireza; Palmer, William E.; Bredella, Miriam A. [Massachusetts General Hospital and Harvard Medical School, Division of Musculoskeletal Imaging and Intervention, Boston, MA (United States); Kwon, Young-Min [Massachusetts General Hospital and Harvard Medical School, Department of Orthopedics, Boston, MA (United States); Torriani, Martin [Massachusetts General Hospital and Harvard Medical School, Division of Musculoskeletal Imaging and Intervention, Boston, MA (United States); Massachusetts General Hospital, Division of Musculoskeletal Imaging and Intervention Department of Radiology, Boston, MA (United States)

    2015-12-15

    To examine the effect of total hip arthroplasty (THA) on ischiofemoral (IF) and quadratus femoris (QF) spaces with the hypothesis that THA does not affect ischiofemoral relationships. The study was IRB approved and complied with HIPAA guidelines. We identified consecutive MR examinations (pelvis and/or hip) obtained at our institution in adults (≥18 years old) screened for THA-related complications. Native hips from the same individuals served as controls. We collected medical record data including age, gender, surgical history, and THA designs. Two radiologists independently measured the IF-RAD and IF-MRI (IF space on radiographs and MR imaging, respectively) and QF space (on MR imaging). Groups were compared using ANCOVA controlled for gender. The study group comprised 250 hips (132 subjects; 162 post-THA and 88 native hips). Subjects were aged 59 ± 10 years, with 66 males and 66 females. Comparison of IF-MRI and QF spaces between native and post-THA hips showed no differences (P > 0.12) and IF-RAD was higher in post-THA subjects (P = 0.01). No differences in the IF-MRI and QF spaces were present between native hips and different THA designs (P > 0.4). IF-RAD of metal-on-metal THA was higher than that of native hips (P = 0.01) and trended higher than ceramic-on-polyethylene THA (P = 0.08), with the remaining comparisons showing no significant differences (P > 0.4). Radiographic- and MRI-based measures in patients with standard THA do not show narrowing of IF and QF spaces. (orig.)

  2. Clinical and functional outcome of the Thrust Plate Prosthesis: short- and medium-term results.

    Science.gov (United States)

    Steens, W; Rosenbaum, D; Goetze, C; Gosheger, G; van den Daele, R; Steinbeck, J

    2003-08-01

    The purpose of this study was to objectively assess the functional outcome after implantation of a Thrust Plate Prosthesis. This retrospective study compared the gait patterns of 33 patients to a control group. Few studies have been published about this type of prosthesis describing clinical and radiographic outcome. Even though the evaluation of the functional outcome is a commonly accepted way to measure the success of an implant it has not been reported in previous studies. Beside clinical (SF-36, and Harris Hip Score) and radiographic evaluation subjects were examined by three dimensional gait analysis and surface electromyography from seven leg and trunk muscles bilaterally. The average Harris Hip Score was 85.7 points, and the SF-36 only differed significantly from controls regarding physical functioning. The radiography showed considerable radiolucencies under the Thrust Plate. Kinematic parameters indicated a slight impairment of the operated limb. The analysis revealed a decreased hip (28.2%) and knee (51.2%) range of motion during gait. The joint moments on the operated side were reduced in hip (72%) and knee abduction (59%) in comparison to controls. The average electromyographic parameters indicated a significantly higher mean and peak amplitude of the tensor fasciae latae (mean 56%, peak 54%), and gluteus medius (mean 33%, peak 21%) and a lower peak activity of the gluteus maximus (19%). The results indicate a generally good functional outcome even though a slightly asymmetrical loading was observed. No major limitations in physical functioning and health-related quality of life was seen. The radiographic signs of loosening might indicate difficulties in achieving the proximal load transfer of this implant. The data provided in this study may serve to establish the Thrust Plate Prosthesis as an alternative procedure in total hip replacement in younger patients.

  3. Intraocular retinal prosthesis.

    Science.gov (United States)

    Humayun, M S

    2001-01-01

    ). In all groups, short duration pulses (40, 80, and 120 microseconds) were more efficient in terms of total charge (the product of pulse amplitude and pulse duration) than longer (500 and 1,000 microseconds) pulses (P < .05). In all groups, applying a pulse train did not lead to more efficient charge usage (P < .05). Psychophysical experiments: In high-contrast tests, facial recognition rates of over 75% were achieved for all subjects with dot sizes of up to 31.5 minutes of arc when using a 25 x 25 grid with 4.5 arc minute gaps, a 30% dropout rate, and 6 gray levels. Even with a 4 x 4 array of pixels, some subjects were able to accurately describe 2 of the objects. Subjects who were able to read the 4-pixel letter height sentences (on the 6 x 10 and 16 x 16 array) seemed to have a good scanning technique. Scanning at the proper velocity tends to bring out more contrast in the lettering. The reading speed for the 72-point font is a bit slower than for the next smaller font. This may be due to the limited number of letters (3) visible in the window with this large font. Specific parameters needed to stimulate the retina were identified. Delineating the optimum parameters will decrease the current requirements. Psychophysical tests show that with limited pixels and image processing, useful vision is possible. Both these findings should greatly simplify the engineering of an electronic retinal prosthesis.

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

    Directory of Open Access Journals (Sweden)

    Gavaskar Ashok S

    2012-12-01

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

  5. Design of a technique for the radiotherapy treatment of patients of prostate with bilateral prosthetic hip; Diseno de una tecnica para el tratamiento radioterapico de pacientes de prostata con protesis bilateral de cadera

    Energy Technology Data Exchange (ETDEWEB)

    Camacho, C.; Perez-Alija, J.; Olivares, S.; Loscos, S.; Pedro, A.

    2013-07-01

    The design of the plan of treatment of patients who have to undergo radical radiotherapy of prostate and that incorporate some sort of hip prosthesis is usually complex. the case of a patient's prostatic bed with bilateral hip prosthesis to assess radical radiotherapy to the 70Gy in bed. The objective of this paper is to present the chosen technique designed for this treatment. (Author)

  6. A Case of Acute Prosthesis Migration after Femoral Head Replacement due to Osteomalacia by FGF23-Induced Tumor

    Directory of Open Access Journals (Sweden)

    Shinya Hayashi

    2012-01-01

    Full Text Available Fibroblast growth factor 23 (FGF23 was recently identified as an important factor involved in the development of hypophosphatemic rickets and osteomalacia. We experienced a rare case of acute prosthesis migration after hemihip arthroplasty due to FGF23-induced tumor. The patient underwent femoral head replacement because of femoral neck fracture, but prosthesis migration was occurred at 1 week after operation. The patient took various examinations, and FGF23-induced tumor was found in his right wrist. The tumor was resected, and he underwent total hip arthroplasty 8 month later. Finally, he was able to obtain free gait without pain.

  7. The Thrust Plate Prosthesis: long-term clinical and radiological results.

    Science.gov (United States)

    Diederix, Leon W; Van Winterswijk, Peter J T S; Schouten, Sander B; Bakx, Pieter A G M; Huij, Jaap

    2013-06-01

    The Thrust Plate Prosthesis is a femoral implant designed for total hip arthroplasty, based on the principles of physiologic loading of the metaphysis of the proximal femur, and preserving the bone stock. This study presents the long-term clinical and radiological results of 34 patients with 36 Thrust Plate Prostheses. In a retrospective analysis, we investigated the reoperation-free survival as well as the clinical and radiological results. Mean age at operation was 51 +/- 6.4 years. Mean follow-up length was 11.9 +/- 1.6 years. Reoperation-free survival was 88.9%. Four (11.1%) reoperations were performed, in three patients due to aseptic loosening and in one patient because of a fracture distal to the lateral plate. Three of the reoperations were performed between 12 and 32 months postoperatively. The major complaint was pain at the lateral side of the hip (44%). Radiolucencies did not exceed 1 mm, but 35% of the hips showed resorption of the cortex directly under the thrust plate, together with cancellous bone hypertrophy at the calcar, noted in 97%. Because of the relatively high reoperation-free survival and favourable radiological results, the Thrust Plate Prosthesis appears as a possible alternative to stemmed total hip arthroplasty, especially in relatively young patients.

  8. A clinical, radiological and computational analysis of the thrust plate prosthesis in young patients.

    Science.gov (United States)

    Gerich, T G; Wilmes, P; Nackenhorst, U; Gösling, T; Ziefle, M; Krettek, C

    2011-01-01

    A thrust plate prosthesis can be used as an alternative to a conventional stem prosthesis, preserving the diaphyseal bone stock. Recent findings however predict a higher rate of aseptic loosening than with intramedullary devices. The purpose of our investigation was to compare the clinical outcome and radiological findings with a finite element analysis of bone remodeling. The hypothesis was that aseptic loosening after thrust plate prosthesis of the hip is inherent to the design. From 1997 to 2001, 58 thrust plates were implanted in 52 patients. Average age at the time of surgery was 40.9 years. Ninety four percent returned for follow up at an average of 26 months. A finite element model of the thrust plate within the femur was developed and stress shielding as well as bone remodeling were analyzed. A total of 4 patients required revision surgery (6.9%). Data from the finite element analysis revealed an inherent failure mechanism to the implant, facilitating stress shielding and loosening. Lacking the ideal total hip prosthesis in young patients, the thrust plate can still be regarded as a feasible implant. However, surgeons and patients should be aware of possible mechanical problems regarding the design of the thrust plate. There is evidence that thrust plate prostheses are prone to early aseptic loosening. Clinical and radiological observations are in agreement with the results from the numerical simulations. Stress concentrations computed at the leash are interpreted as an explanation for leash pain. The authors regard computational methods as an aid to improve existing prosthesis design and future developments.

  9. Thrust plate prosthesis for proximal femoral deformity: a series of 15 patients.

    Science.gov (United States)

    Karatosun, Vasfi; Unver, Bayram; Gültekin, Alper; Günal, Izge

    2010-01-01

    Patients with coxarthrosis and proximal femoral deformity experience problems with total hip arthroplasty. A custom-made prosthesis or a proximal osteotomy is required for such cases, and these also increase the rate of complications. The purpose of this study was to evaluate the results of the thrust plate prosthesis (TPP) in patients with deformity of the proximal femur. Fifteen patients (7 females, 8 males) with a mean age of 56.4 years (range 19-75 years) at the time of the surgery were included in the study. The etiology was traumatic coxarthrosis in 12, and nonunion of a femoral neck fracture with osteonecrosis of the femoral head in the remaining three. While the femoral component was a third-generation TPP in all patients, the acetabular component was a Protek expansion cup in 12, and a cementless standard cup in three patients. All operations were performed through a Hardinge approach. Patients were followed up for at least 3 years (range 36-116 months) and evaluated clinically with the Harris Hip Score. The mean preoperative Harris Hip Score increased from 51.2 (range 15-79) to 92.7 (range 60-100) at the latest assessment. In two cases, loosening of the femoral component was observed in zone 3, both 12 months postoperatively. One was replaced by an intramedullary prosthesis, and the other was asymptomatic. TPP is a good alternative for patients with malformations of the proximal femur. The use of TPP avoids technical difficulties and a custom-made prosthesis.

  10. THR Simulator – the software for generating radiographs of THR prosthesis

    Directory of Open Access Journals (Sweden)

    Hou Sheng-Mou

    2009-01-01

    Full Text Available Abstract Background Measuring the orientation of acetabular cup after total hip arthroplasty is important for prognosis. The verification of these measurement methods will be easier and more feasible if we can synthesize prosthesis radiographs in each simulated condition. One reported method used an expensive mechanical device with an indeterminable precision. We thus develop a program, THR Simulator, to directly synthesize digital radiographs of prostheses for further analysis. Under Windows platform and using Borland C++ Builder programming tool, we developed the THR Simulator. We first built a mathematical model of acetabulum and femoral head. The data of the real dimension of prosthesis was adopted to generate the radiograph of hip prosthesis. Then with the ray tracing algorithm, we calculated the thickness each X-ray beam passed, and then transformed to grey scale by mapping function which was derived by fitting the exponential function from the phantom image. Finally we could generate a simulated radiograph for further analysis. Results Using THR Simulator, the users can incorporate many parameters together for radiograph synthesis. These parameters include thickness, film size, tube distance, film distance, anteversion, abduction, upper wear, medial wear, and posterior wear. These parameters are adequate for any radiographic measurement research. This THR Simulator has been used in two studies, and the errors are within 2° for anteversion and 0.2 mm for wearing measurement. Conclusion We design a program, THR Simulator that can synthesize prosthesis radiographs. Such a program can be applied in future studies for further analysis and validation of measurement of various parameters of pelvis after total hip arthroplasty.

  11. Elektra prosthesis for trapeziometacarpal osteoarthritis

    DEFF Research Database (Denmark)

    Klahn, A; Nygaard, Mads; Gvozdenovic, R

    2012-01-01

    We present a prospective follow-up of 39 Elektra prostheses in 37 patients (32 women and five men), with a mean age of 56.5 (range 46-71) years; 34 patients had osteoarthritis and three had rheumatoid arthritis. Patients were followed using clinical examination, including measurement of pain on a...... be the key problem in treating trapeziometacarpal osteoarthritis using a total prosthesis....

  12. Orthostatic intolerance during early mobilization after fast-track hip arthroplasty

    DEFF Research Database (Denmark)

    Jans, O; Bundgaard-Nielsen, M; Solgaard, S

    2012-01-01

    BACKGROUND: /st>Early postoperative mobilization is a cornerstone in fast-track total hip arthroplasty (THA), but postoperative orthostatic intolerance (OI) may delay early recovery or lead to fainting, falls, and prosthesis dislocation or fracture. However, the prevalence and pathophysiology of OI...

  13. Patient Needs for an Ambulant Dislocation Alert System Following Total Hip Arthroplasty

    NARCIS (Netherlands)

    Huis in't Veld, Rianne; Peters, Anil; Vollenbroek-Hutten, Miriam Marie Rosé; Hermens, Hermanus J.; van den Hoven, Carmen

    2017-01-01

    INTRODUCTION: One of the major complications in total hip arthroplasty (THA) is dislocation of the prosthesis. To prevent early dislocation, patients are instructed with movement restrictions. The first goal in this development is to obtain insight in the movement restrictions that are reported to

  14. Plannig strategy for radiotherapic treatment oa patients with prosthetic hip. Solution of intensity

    International Nuclear Information System (INIS)

    Puertolas Hernandez, J. R.; Iriondo Igerabide, U.; Lozano Flores, F. J.; Pino Leon, C.; Larretxea Etxarri, R.

    2013-01-01

    The intensity modulated radiation therapy (IMRT) can offer better plans, defining the prosthesis as critical structure that limit the dose. In our case, in the last year we have made five planning hip replacement cases, and one case with two prostheses (bilateral). We are introducing the strategy we use to carry out these planning. (Author)

  15. Quantitating the effect of prosthesis design on femoral remodeling using high-resolution region-free densitometric analysis (DXA-RFA)

    DEFF Research Database (Denmark)

    Farzi, Mohsen; Morris, Richard M; Penny, Jeannette

    2017-01-01

    Dual energy X-ray absorptiometry (DXA) is the reference standard method used to study bone mineral density (BMD) after total hip arthroplasty (THA). However, the subtle, spatially complex changes in bone mass due to strain-adaptive bone remodeling relevant to different prosthesis designs are not ......Dual energy X-ray absorptiometry (DXA) is the reference standard method used to study bone mineral density (BMD) after total hip arthroplasty (THA). However, the subtle, spatially complex changes in bone mass due to strain-adaptive bone remodeling relevant to different prosthesis designs...... using scans acquired during two previous randomized clinical trials (2004 to 2009); one comparing three cemented prosthesis design geometries, and the other comparing a hip resurfacing versus a conventional cementless prosthesis. DXA RFA resolved subtle differences in magnitude and area of bone...... remodeling between prosthesis designs not previously identified in conventional DXA analyses. A mean bone loss of 10.3%, 12.1%, and 11.1% occurred for the three cemented prostheses within a bone area fraction of 14.8%, 14.4%, and 6.2%, mostly within the lesser trochanter (p 

  16. Impact of a stance phase microprocessor-controlled knee prosthesis on level walking in lower functioning individuals with a transfemoral amputation.

    Science.gov (United States)

    Eberly, Valerie J; Mulroy, Sara J; Gronley, JoAnne K; Perry, Jacquelin; Yule, William J; Burnfield, Judith M

    2014-12-01

    For individuals with transfemoral amputation, walking with a prosthesis presents challenges to stability and increases the demand on the hip of the prosthetic limb. Increasing age or comorbidities magnify these challenges. Computerized prosthetic knee joints improve stability and efficiency of gait, but are seldom prescribed for less physically capable walkers who may benefit from them. To compare level walking function while wearing a microprocessor-controlled knee (C-Leg Compact) prosthesis to a traditionally prescribed non-microprocessor-controlled knee prosthesis for Medicare Functional Classification Level K-2 walkers. Crossover. Stride characteristics, kinematics, kinetics, and electromyographic activity were recorded in 10 participants while walking with non-microprocessor-controlled knee and Compact prostheses. Walking with the Compact produced significant increase in velocity, cadence, stride length, single-limb support, and heel-rise timing compared to walking with the non-microprocessor-controlled knee prosthesis. Hip and thigh extension during late stance improved bilaterally. Ankle dorsiflexion, knee extension, and hip flexion moments of the prosthetic limb were significantly improved. Improvements in walking function and stability on the prosthetic limb were demonstrated by the K-2 level walkers when using the C-Leg Compact prosthesis. Understanding the impact of new prosthetic designs on gait mechanics is essential to improve prescription guidelines for deconditioned or older persons with transfemoral amputation. Prosthetic designs that improve stability for safety and walking function have the potential to improve community participation and quality of life. © The International Society for Prosthetics and Orthotics 2013.

  17. Design of compensators for patients with hip prostheses undergoing pelvic irradiation

    International Nuclear Information System (INIS)

    Alecu, R.; Feldmeier, J.; He, T.; Alecu, M.; Court, W.; Orton, C.G.

    1995-01-01

    The perturbations in the dose distribution caused by a hip prosthesis when treating pelvic cancers have been evaluated and found to be significant by several investigators. Treatment techniques not including the prosthesis are often not the best choice. The goal of this study is to investigate the feasibility and usefulness of design of compensators in routine clinical practice for any kind of hip prosthesis. The calculation procedures and the algorithms developed by the authors for generating the compensators are described for two systems: one based on a locally developed 3-D computerized treatment planning system and an other one practicable in any institution which does not have access to a 3D treatment planning system or CT. The methodology to create the compensators for a patient is explained. To evaluate the constructed compensators in phantom and in vivo measurements were performed. The results are presented along with a comparison between the two methods

  18. Contact dermatitis from a prosthesis.

    Science.gov (United States)

    Munoz, Carla A; Gaspari, Anthony; Goldner, Ronald

    2008-01-01

    Patients wearing a prosthesis face a wide variety of medical problems. Skin complications have long been recognized, but their prevalence is still unknown. The most frequently reported disorders are allergic contact dermatitis (ACD), acroangiodermatitis, epidermoid cysts, epidermal hyperplasia, follicular hyperkeratosis, verrucous hyperplasia, bullous diseases, hyperhidrosis, infections, malignancies, and ulcerations. Contact dermatitis represents one-third of the dermatoses in amputees wearing prostheses. All patients who are suspected of having ACD should be patch tested with standard allergen series as well as materials from the patient's own prosthesis, topical medicaments, moisturizers, and cosmetics. We report a patient with an ACD to mixed dialkyl thiourea present in the rubber parts of his below-the-knee prosthesis. Thiourea derivates are used as accelerators in the manufacture of chloroprene rubber and as fixatives in photography and photocopy paper. Allergy to thiourea is relatively uncommon; different studies have shown a prevalence of 0.7% up to 2.4% in patch-tested patients. Thiourea derivates are often the allergic sources in ACD involving high-grade rubber products made of neoprene such as diving suits, protective goggles, knee braces, and continuous positive airway pressure masks. They are also present in the rubber material of prostheses, as in the case of our patient.

  19. Dosimetry of a silicone breast prosthesis

    International Nuclear Information System (INIS)

    McGinley, P.H.; Powell, W.R.; Bostwick, J.

    1980-01-01

    Dose measurements were conducted in a phantom which simulates breast tissue and in another phantom which simulates a breast containing a silicone prosthesis. No detectable difference was found when the irradiations were carried out with tangential beams of 60 Co radiation. The degree of backscatter and absorption of radiation by the prosthesis and phantom were also similar. A slight decrease in dose of approximately 8% was found at the interface between the prosthesis and muscle-equivalent material

  20. Importance of preclinical evaluation of wear in hip implant designs using simulator machines

    Directory of Open Access Journals (Sweden)

    Rafael Mello Trommer

    Full Text Available ABSTRACT Total hip arthroplasty (THA is a surgical procedure that involves the replacement of the damaged joint of the hip by an artificial device. Despite the recognized clinical success of hip implants, wear of the articulating surfaces remains as one of the critical issues influencing performance. Common material combinations used in hip designs comprise metal-on-polymer (MoP, ceramic-on-polymer (CoP, metal-on-metal (MoM, and ceramic-on-ceramic (CoC. However, when the design of the hip implant is concerned besides the materials used, several parameters can influence its wear performance. In this scenario, where the safety and efficacy for the patient are the main issues, it is fundamental to evaluate and predict the wear rate of the hip implant design before its use in THA. This is one of the issues that should be taken into account in the preclinical evaluation step of the product, in which simulated laboratory tests are necessary. However, it is fundamental that the applied motions and loads can reproduce the wear mechanisms physiologically observed in the patient. To replicate the in vivo angular displacements and loadings, special machines known as joint simulators are employed. This article focuses on the main characteristics related to the wear simulation of hip implants using mechanical simulators, giving information to surgeons, researchers, regulatory bodies, etc., about the importance of preclinical wear evaluation. A critical analysis is performed on the differences in the principles of operation of simulators and their effects on the final results, and about future trends in wear simulation.

  1. Modular taper junction corrosion and failure: how to approach a recalled total hip arthroplasty implant.

    Science.gov (United States)

    Pivec, Robert; Meneghini, R Michael; Hozack, William J; Westrich, Geoffrey H; Mont, Michael A

    2014-01-01

    Corrosion at the modular neck-stem taper junction has become an increasingly important topic as several reports have identified this couple as a possible source for early failure with findings similar to failed metal-on-metal hip arthroplasties. Recently, two different modular stem systems from a single manufacturer were voluntarily recalled due to concerns of failure of the modular taper junction. We discuss how to approach the diagnosis and management of patients with these particular stem systems. We further reviewed the literature to evaluate whether this is a manufacturer-specific defect or indicative of a broader trend. Recent studies appear to implicate the basic design of the neck-stem taper junction, rather than a single manufacturer, which is at high risk for fretting and corrosion. © 2013.

  2. Total Hip Arthroplasty Dislocations Are More Complex Than They Appear: A Case Report of Intraprosthetic Dislocation of an Anatomic Dual-Mobility Implant After Closed Reduction

    Science.gov (United States)

    Waddell, Bradford S.; De Martino, Ivan; Sculco, Thomas; Sculco, Peter

    2016-01-01

    Background: Total hip arthroplasty is a successful operation for the treatment of hip pain. One of the common complications of hip arthroplasty is dislocation. While reduction of standard prosthetic dislocations is highly successful, new prostheses add the potential for new complications. Case Report: We present the case of a patient who experienced intraprosthetic dislocation of an anatomic dual-mobility total hip prosthesis after a closed hip reduction and include the prereduction and postreduction radiographic findings. Conclusion: Emergency department physicians should be aware of intraprosthetic dislocation. This complication can be easily missed because the metal/ceramic femoral head appears to be reduced in the acetabulum. PMID:27303232

  3. Indications of 99mTc-MDP scintigraphy bone scan in the evaluation of painful hip arthroplasties

    International Nuclear Information System (INIS)

    Eder, V.; Baulieu, F.; Secchi, V.; Gautier, B.; Pottier, J.M.; Rosset, P.

    2000-01-01

    The purpose of this study was to determine the indication of bone scintigraphy in hip prosthesis complications. Thirty-six patients and 38 hip prosthesis have had a 99 Tc-MDP scintigraphy in our laboratory between 1995 and 1997. It concerns 32 cemented total prosthesis, 3 intermediate prosthesis and 3 non-cemented total prosthesis. For 14 prosthesis, complication (loosening or infection) was confirmed by surgical operation in 12 cases (4 isolated acetabular complications, 2 isolated femoral loosening, 3 global loosening and 3 infections) or by concordant data from different examinations in 2 cases (global loosening) where intervention was unrealizable. About other patients, absence of complication was confirmed by a favourable evolution lasting at least 12 months. A cetabular and femoral complications were detected by scintigraphy respectively with a sensitivity of 100 % and 90 %, a specificity of 85 % and 78 %, a PPV of 75 % and 60 % and NPV of 100 % and 96 %. High negative predictive value allows to eliminate a prosthesis complication in the case of a normal scintigraphy and to override decision when the clinic and the radiography are doubtful. Scintigraphy may recognize other bone fixation abnormalities which may be responsible of clinical symptomatology. (authors)

  4. The history of biomechanics in total hip arthroplasty

    Directory of Open Access Journals (Sweden)

    Jan Van Houcke

    2017-01-01

    Full Text Available Biomechanics of the hip joint describes how the complex combination of osseous, ligamentous, and muscular structures transfers the weight of the body from the axial skeleton into the appendicular skeleton of the lower limbs. Throughout history, several biomechanical studies based on theoretical mathematics, in vitro, in vivo as well as in silico models have been successfully performed. The insights gained from these studies have improved our understanding of the development of mechanical hip pathologies such as osteoarthritis, hip fractures, and developmental dysplasia of the hip. The main treatment of end-stage degeneration of the hip is total hip arthroplasty (THA. The increasing number of patients undergoing this surgical procedure, as well as their demand for more than just pain relief and leading an active lifestyle, has challenged surgeons and implant manufacturers to deliver higher function as well as longevity with the prosthesis. The science of biomechanics has played and will continue to play a crucial and integral role in achieving these goals. The aim of this article, therefore, is to present to the readers the key concepts in biomechanics of the hip and their application to THA.

  5. The History of Biomechanics in Total Hip Arthroplasty.

    Science.gov (United States)

    Houcke, Jan Van; Khanduja, Vikas; Pattyn, Christophe; Audenaert, Emmanuel

    2017-01-01

    Biomechanics of the hip joint describes how the complex combination of osseous, ligamentous, and muscular structures transfers the weight of the body from the axial skeleton into the appendicular skeleton of the lower limbs. Throughout history, several biomechanical studies based on theoretical mathematics, in vitro , in vivo as well as in silico models have been successfully performed. The insights gained from these studies have improved our understanding of the development of mechanical hip pathologies such as osteoarthritis, hip fractures, and developmental dysplasia of the hip. The main treatment of end-stage degeneration of the hip is total hip arthroplasty (THA). The increasing number of patients undergoing this surgical procedure, as well as their demand for more than just pain relief and leading an active lifestyle, has challenged surgeons and implant manufacturers to deliver higher function as well as longevity with the prosthesis. The science of biomechanics has played and will continue to play a crucial and integral role in achieving these goals. The aim of this article, therefore, is to present to the readers the key concepts in biomechanics of the hip and their application to THA.

  6. Usefulness of positron emission tomography (TEP) in the assessment of osteo-articular prosthesis; Utilite de la tomographie par emission de positons (TEP) dans l'etude des protheses osteo-articulaires

    Energy Technology Data Exchange (ETDEWEB)

    Maldonado, A.; Suarez, J.P.; Dominguez, M.L. [Centro PET Complutense, Madrid (Spain)

    2004-12-15

    Joint arthroplasty is performed with increasing frequency as the population ages. Loosening or infection of the prosthesis is a relatively common event that can limit the lifetime of a prosthesis. Accuracy differentiation between aseptic and septic loosening of the prosthesis remains a challenge because of the consequences for patient management. Moreover, an early diagnosis of infected hip prosthesis is very important for optimal and cost-effective management. Various approaches have developed to visualize infection and inflammation by nuclear medicine techniques. Recently positron emission tomography (PET) with fluorine-l8 labelled 2 fluoro-2-deoxyglucose ({sup 18}F-FDG) has been shown to delineate infectious and inflammatory foci with high sensitivity owing to the increased glucose metabolism in inflammatory cells. In this paper we review the role of FDG-PET in this common differential diagnosis in patients with total knee and hip prostheses. Different patterns of FDG-PET interpretation have been described as wed as methodological aspects. (author)

  7. Clinical and radiographic results of total hip arthroplasty in dogs: 96 cases (1986-1992)

    International Nuclear Information System (INIS)

    Massat, B.J.; Vasseur, P.B.

    1994-01-01

    Results of total hip arthroplasty in 84 dogs (96 hips) were evaluated. Eight (9.5% of) the 84 dogs developed 1 or move complications after total hip arthroplasty. Complications resolved or were corrected in 4 of the dogs; all 4 ultimately achieved good or excellent hip function. Complications necessitated removal of the Prosthesis in the other 4 dogs; 3 ultimately achieved fair hip function and 1 had only poor hip function. Therefore, after resolution of complications, 96% of the hips had good or excellent function. Force plate analysis was performed on 6 dogs with excellent hip function; peak vertical force for the limb that had been operated on was greater than or equal to peak vertical force for the contralateral limb. Radiographically, a radiolucent zone was visible around the acetabular component in 89% of the hips and around the femoral component in 26%. The radiolucent zone around the acetabular and femoral components widened in 14% (6 of 43) and 27% (3 of 11), respectively, of the hips with adequate radiographic follow-up. Aseptic loosening of the acetabular component developed in 3 (3%) of 96 hips, one was successfully revised. Aseptic loosening of the femoral component was not apparent in any of the dogs in this study. Other complications included femoral fracture (n = 3), neurapraxia (3), luxation(1), and unexplained lameness that required implant removal (1). None of the dogs had evidence of wound infection

  8. A prosthesis-specific multi-link segment model of lower-limb amputee sprinting.

    Science.gov (United States)

    Rigney, Stacey M; Simmons, Anne; Kark, Lauren

    2016-10-03

    Lower-limb amputees commonly utilize non-articulating energy storage and return (ESAR) prostheses for high impact activities such as sprinting. Despite these prostheses lacking an articulating ankle joint, amputee gait analysis conventionally features a two-link segment model of the prosthetic foot. This paper investigated the effects of the selected link segment model׳s marker-set and geometry on a unilateral amputee sprinter׳s calculated lower-limb kinematics, kinetics and energetics. A total of five lower-limb models of the Ottobock ® 1E90 Sprinter were developed, including two conventional shank-foot models that each used a different version of the Plug-in-Gait (PiG) marker-set to test the effect of prosthesis ankle marker location. Two Hybrid prosthesis-specific models were then developed, also using the PiG marker-sets, with the anatomical shank and foot replaced by prosthesis-specific geometry separated into two segments. Finally, a Multi-link segment (MLS) model was developed, consisting of six segments for the prosthesis as defined by a custom marker-set. All full-body musculoskeletal models were tested using four trials of experimental marker trajectories within OpenSim 3.2 (Stanford, California, USA) to find the affected and unaffected hip, knee and ankle kinematics, kinetics and energetics. The geometry of the selected lower-limb prosthesis model was found to significantly affect all variables on the affected leg (p prosthesis-specific spatial, inertial and elastic properties from full-body models significantly affects the calculated amputee gait characteristics, and we therefore recommend the implementation of a MLS model. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Short- and medium-term results of the thrust plate prosthesis in patients with polyarthritis.

    Science.gov (United States)

    Fink, B; Siegmüller, C; Schneider, T; Conrad, S; Schmielau, G; Rüther, W

    2000-01-01

    The thrust plate prosthesis is an implant with metaphyseal fixation to the proximal femur, which leaves the diaphyseal bone untouched. Therefore, this implant is preferred in younger patients. It is dependent on good bone quality in the proximal femur. Because the bone quality is reduced in patients with polyarthritis, this kind of endoprosthesis may have a higher failure rate than conventional stemmed endoprostheses in these patients. Therefore, in patients with polyarthritis, even short- and medium-term results of the thrust plate prosthesis should be analyzed. In all, 47 thrust plate prostheses were implanted in 42 patients with polyarthritis (29 with rheumatoid arthritis, 6 with juvenile chronic arthritis, and 7 with spondylarthritis) and followed prospectively. The average age at operation was 40.8+/-10.7 years. Each patient was clinically and radiologically examined preoperatively, 3 and 6 months after the operation, and at the end of each postoperative year. The mean follow-up was 26.1+/-10.7 months. The clinical findings were evaluated using the Harris hip score. Radiologically, 8 different zones of the thrust plate prosthesis were analyzed for radiolucencies. During the 1st year, the Harris hip score rose continuously from the preoperative average of 42.4+/-6.5 points to 78.8+/-10.3 points 3 months postoperatively, 82.3+/-9.8 points 6 months postoperatively, and 86.8+/-10.1 points 1 year after the operation. The subsequent examinations showed Harris hip score remained at the same level. Five patients (5 joints, 10.6%) had to undergo a revision of the thrust plate prosthesis due to aseptic loosening in 3 and septic loosening in 2. Six prostheses (12.6%) showed radiolucencies, mostly below the thrust plate in zones 1 and 2. Two of them were certainly radiologically loose, which raised the failure rate to 7 of 47 (14.8%). The thrust plate prosthesis improves function and alleviates pain in patients with polyarthritis to a satisfactory degree. Concerning the

  10. An Insight into Methods and Practices in Hip Arthroplasty in Patients with Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Mohammad Saeed Mosleh-shirazi

    2015-01-01

    Full Text Available Total hip arthroplasty (THA has improved the quality of life of patients with hip arthritis. Orthopedic community is striving for excellence to improve surgical techniques and postoperative care. Despite these efforts, patients continue facing postoperative complications. In particular, patients with rheumatoid arthritis display a higher risk of certain complications such as dislocation, periprosthetic infection, and shorter prosthesis durability. In this review we present the current knowledge of hip arthroplasty in patients with rheumatoid arthritis with more insight into common practices and interventions directed at enhancing recovery of these patients and current shortfalls.

  11. An Unexpected Complication of Hip Arthroplasty: Knee Dislocation

    Directory of Open Access Journals (Sweden)

    Serdar Yilmaz

    2015-01-01

    Full Text Available An increasing number of patients with hip fracture have been seen with osteoporosis associated with osteoarthritis. Although knee dislocation is related to high-energy trauma, low-grade injuries can also lead to knee dislocation which is defined as “ultra-low velocity dislocation.” The case reported here is of an 82-year-old patient who presented with a left intertrochanteric hip fracture. Partial arthroplasty was planned because of osteoporosis. In the course of surgery, degenerative arthritic knee was dislocated during the hip reduction maneuver with the application of long traction. The neurovascular examination was intact, but the knee was grossly unstable and was dislocated even in a brace; thus a hinged knee prosthesis was applied nine days after surgery. The patient was mobilized with crutches after the knee prosthesis but exercise tolerance was diminished. In conclusion, it should be emphasized that overtraction must be avoided during the hip reduction maneuver in patients with advanced osteoarthritic knee.

  12. Primary cemented total hip arthroplasty: 10 years follow-up

    Directory of Open Access Journals (Sweden)

    Nath Rajendra

    2010-01-01

    Full Text Available Background: Primary cemented total hip arthroplasty is a procedure for non-traumatic and traumatic affections of the hip. Long term follow-up is required to assess the longevity of the implant and establish the procedure. Indo-Asian literature on long term result of total hip arthroplasty is sparse. We present a 10-year follow-up of our patients of primary cemented total hip arthroplasty. Materials and Methods: We operated 31 hips in 30 patients with primary cemented total hip arthroplasty. We followed the cases for a minimum period of 10 years with a mean follow-up period of 12.7 years. The mean age of the patients was 60.7 years (range 37-82 yrs male to female ratio was 2:1. The clinical diagnoses included - avascular necrosis of femoral head (n=15, sero positive rheumatoid arthritis (n=5, seronegative spondylo-arthropathy (n=4, neglected femoral neck fractures (n=3, healed tubercular arthritis (n=2 and post traumatic osteoarthritis of hip (n=2. The prostheses used were cemented Charnley′s total hip (n=12 and cemented modular prosthesis (n=19. The results were assessed according to Harris hip score and radiographs taken at yearly intervals. Results: The mean follow-up is 12.7 yrs (range 11-16 yrs Results in all operated patients showed marked improvement in Harris hip score from preoperative mean 29.2 to 79.9 at 10 years or more followup. However, the non-inflammatory group showed more sustained long term improvement as compared to the inflammatory group, as revealed by the Harris hip score. Mean blood loss was 450ml (±3.7 ml, mean transfusion rate was 1.2 units (±.3. The complications were hypotension (n=7, shortening> 1.5 cm (n=9, superficial infection (n=2 and malposition of prosthesis (n=1. Conclusion: The needs of Indian Asian patients, vary from what is discussed in literature. The pain tolerance is greater than western population and financial constraints are high. Thus revision surgery among Indian-Asian patients is less compared

  13. Acetabular QCT in Total Hip Arthroplasty - a reliability study using porcine hips

    DEFF Research Database (Denmark)

    Mussmann, Bo Redder; Overgaard, Soren; Torfing, Trine

    Introduction Periprosthetic bone loss is considered a predictor of aseptic loosening of the acetabular component in total hip arthroplasty. However, no studies have shown this association. This may be explained by the limitations of imaging methods previously used. Dual energy CT (DECT) has...... previously shown better delineation of the interface between bone and prosthesis and may be beneficial in quantitative analysis of bone loss close to the implant as compared to single energy computed tomography (SECT). The purpose of this porcine ex-vivo study was to test the intra-observer agreement...... and reliability of bone mineral density measurements (BMD) in close proximity of the acetabular cup using SECT and DECT images and 3D segmentation software. Materials and methods 22 acetabular cups (12 cemented, 10 un-cemented) were inserted in porcine hip specimens ex vivo. A femoral stem was attached to each...

  14. Prosthesis failure within 2 years of implantation is highly predictive of infection.

    Science.gov (United States)

    Portillo, María Eugenia; Salvadó, Margarita; Alier, Albert; Sorli, Lluisa; Martínez, Santos; Horcajada, Juan Pablo; Puig, Lluis

    2013-11-01

    The outcome of revision surgery depends on accurate determination of the cause of prosthesis failure because treatment differs profoundly among aseptic loosening, mechanical failure, and prosthetic joint infections (PJI). We sought to determine (1) the predictive role of the interval from primary to revision surgery in determining the reason for prosthesis failure of a hip, knee, shoulder, or elbow arthroplasty, and (2) whether positive cultures during revision surgery for aseptic loosening were associated with shorter event-free survival of the prosthesis. All patients undergoing revision surgery between July 2010 and January 2012 were included in a prospective cohort of 112 patients, and were classified as having had failure from aseptic loosening (56%), mechanical failure (15%), or PJI (29%). To make the diagnosis of PJI, at surgery we used a standardized enhanced diagnostic approach in all patients including sampling of five periprosthetic tissue specimens, sonication of removed prosthetic components, prolonged incubation of aerobic and anaerobic cultures, and multiplex PCR of sonication fluid in aseptic loosening cases. Kaplan-Meier survival and Cox proportional hazards regression analysis were performed. The median time from primary to revision surgery was (p prosthesis failure.

  15. Prosthesis infections after orthopedic joint replacement

    DEFF Research Database (Denmark)

    Song, Zhijun; Borgwardt, Lotte; Høiby, Niels

    2013-01-01

    Prosthesis-related infection is a serious complication for patients after orthopedic joint replacement, which is currently difficult to treat with antibiotic therapy. Consequently, in most cases, removal of the infected prosthesis is the only solution to cure the infection. It is, therefore...

  16. BIORESORBABLE POLYMERIC MENISCAL PROSTHESIS: STUDY IN RABBITS

    Science.gov (United States)

    Cardoso, Tulio Pereira; de Rezende Duek, Eliana Aparecida; Amatuzzi, Marco Martins; Caetano, Edie Benedito

    2015-01-01

    Objective: To induce growth of a neomeniscus into the pores of a prosthesis in order to protect the knee joint cartilage. Methods: 70 knees of 35 New Zealand rabbits were operated. The rabbits were five to seven months old, weighed 2 to 3.8 kilograms, and 22 were male and 13 were female. Each animal underwent medial meniscectomy in both knees during a single operation. A bioabsorbable polymeric meniscal prosthesis composed of 70% polydioxanone and 30% L-lactic acid polymer was implanted in one side. The animals were sacrificed after different postoperative time intervals. The femoral condyles and neomeniscus were subjected to histological analysis. Histograms were used to measure the degradation and absorption of the prosthesis, the growth of meniscal tissue in the prosthesis and the degree of degradation of the femoral condyle joint cartilage. Results: The data obtained showed that tissue growth histologically resembling a normal meniscus occurred, with gradual absorption of the prosthesis, and the percentages of chondrocytes on the control side and prosthesis side. Conclusion: Tissue growth into the prosthesis pores that histologically resembled the normal rabbit meniscus was observed. The joint cartilage of the femoral condyles on the prosthesis side presented greater numbers of chondrocytes in all its layers. PMID:27022549

  17. Penile Prosthesis Implantation in Priapism.

    Science.gov (United States)

    Yücel, Ömer Barış; Pazır, Yaşar; Kadıoğlu, Ateş

    2018-04-01

    Priapism is defined as a full or partial erection lasting longer than 4 hours after sexual stimulation and orgasm or unrelated to sexual stimulation. The main goal of priapism management is to resolve the episode immediately to preserve erectile function and penile length. Corporal smooth muscle necrosis is likely to have already occurred, and medically refractory erectile dysfunction is expected in patients with a protracted episode. Penile prosthesis implantation (PPI) in the early or late phase of priapism can restore erectile function. To review the literature on PPI in priapism. A PubMed search of all English-language articles published before 2017 was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement using the following search terms: penile prosthesis implantation, priapism, and corporal fibrosis. All publications reporting on PPI during or after priapism episodes were included for review. Three types of priapism were reviewed for management using PPI. Surgical techniques, outcomes, and patient satisfaction were reported. Early implantation (during the episode) is technically easier and has lower complication rates compared with delayed (electively, after the erectile dysfunction is observed) surgery. Immediate PPI also allows preservation of penile length, which is related to higher satisfaction rates. The paradigm is shifting toward immediate PPI in the management of ischemic priapism. Patients with non-ischemic priapism or recurrent priapism, even without a major ischemic episode, are at high risk for erectile dysfunction and are candidates for PPI. Yücel ÖB, Pazır Y, Kadıoğlu A. Penile Prosthesis Implantation in Priapism. Sex Med Rev 2018;6:310-318. Copyright © 2017. Published by Elsevier Inc.

  18. Smartphone supported upper limb prosthesis

    Directory of Open Access Journals (Sweden)

    Hepp D.

    2015-09-01

    Full Text Available State of the art upper limb prostheses offer up to six active DoFs (degrees of freedom and are controlled using different grip patterns. This low number of DoFs combined with a machine-human-interface which does not provide control over all DoFs separately result in a lack of usability for the patient. The aim of this novel upper limb prosthesis is both offering simplified control possibilities for changing grip patterns depending on the patients’ priorities and the improvement of grasp capability. Design development followed the design process requirements given by the European Medical Device Directive 93/42 ECC and was structured into the topics mechanics, software and drive technology. First user needs were identified by literature research and by patient feedback. Consequently, concepts were evaluated against technical and usability requirements. A first evaluation prototype with one active DoF per finger was manufactured. In a second step a test setup with two active DoF per finger was designed. The prototype is connected to an Android based smartphone application. Two main grip patterns can be preselected in the software application and afterwards changed and used by the EMG signal. Three different control algorithms can be selected: “all-day”, “fine” and “tired muscle”. Further parameters can be adjusted to customize the prosthesis to the patients’ needs. First patient feedback certified the prosthesis an improved level of handling compared to the existing devices. Using the two DoF test setup, the possibilities of finger control with a neural network are evaluated at the moment. In a first user feedback test, the smartphone based software application increased the device usability, e.g. the change within preselected grip patterns and the “tired muscle” algorithm. Although the overall software application was positively rated, the handling of the prosthesis itself needs to be proven within a patient study to be

  19. Bone cement implantation syndrome in hip replacement procedure

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    Onur Palabiyik

    2013-06-01

    Full Text Available Total hip replacement procedures are common in geriatric patients with osteoarthrosis of the hip or femur fracture. We planned combined spinal epidural anesthesia for total hip replacement operation due to femur fracture in a ninety-five female case with cardiorespiratory failure. Although the regional anesthesia had applied smoothly, intraoperative cardiac arrest during the placement of cement was thought to be a case with bone cement implantation syndrome. Bone cement implantation syndrome is occured in cemented prosthesis operations and a life-threatened complication. Clinic presentation is characterized by hypoxia, hypotension, unexpected loss of consciousness and cardiac arrest. Mortality rate due to bone cement implantation syndrome is approximately 0.1%. In this present, we examined bone cement implantation syndrome, which is a severe complication. [J Contemp Med 2013; 3(2.000: 121-124

  20. Concomitant achondroplasia and developmental dysplasia of the hip

    Directory of Open Access Journals (Sweden)

    Tennison L. Malcolm, MD

    2015-12-01

    Full Text Available Achondroplasia (ACH is the most common form of hereditary dwarfism and presents with multiple musculoskeletal anomalies but is not normally associated with premature hip arthritis. Developmental dysplasia of the hip (DDH is a spectrum of disease resulting in shallow acetabular depth and a propensity for chronic femoral subluxation or dislocation; it is among the most common causes of premature arthritis. This case report describes the diagnosis of symptomatic DDH in a patient with ACH and highlights difficulties of primary total hip arthroplasty (THA as a treatment option. Intraoperative radiographic imaging is advised to ensure proper prosthesis placement. Femoral osteotomy may aid visualization, reduction, and avoidance of soft tissue injury. Concomitant ACH and DDH is a challenging problem that can be successfully treated with modified THA.

  1. Unicondylar knee prosthesis: our experience.

    Science.gov (United States)

    Valentini, Roberto; De Fabrizio, Giovanni; Piovan, Gianluca; Stasi, Alessandro

    2014-07-28

    To compare unicompartmental knee arthroplasty with "all poly" tibial component and "metal back" from a clinical and functional point of view. We evaluated prospectively 50 patients who underwent unicompartmental knee replacement at the Orthopedic Clinic of the University of Trieste. Patients were split into two groups (A and B); in patients from group A has been implanted a Mitus prosthesis (Link) with "all poly" tibial component, in patients from Group B has been implanted an Allegretto prosthesis (Zimmer) with a "metal back" tibial component. The mean follow-up was 36 months. All patients were evaluated using the Knee Society Score. The mean preoperative Knee Society Score (objective and functional) was found to be respectively 48 and 49 or the group A and group B; post-operative score was found to be of 95 and 94 respectively for Group A and group B. The average post-operative ROM was 125 degrees (range, 85-140 degrees) for group A and 130° (range 90°-145°) for group B. No differences were found between implants with "all poly" tibial component (thickness to be used must be greater than 6 mm) and those with the "metal back". We believe that to achieve positive results over time is important the carefully selection of the patients and the accurate positioning of components.

  2. Hip joint replacement - slideshow

    Science.gov (United States)

    ... medlineplus.gov/ency/presentations/100006.htm Hip joint replacement - series—Normal anatomy To use the sharing features ... M. Editorial team. Related MedlinePlus Health Topics Hip Replacement A.D.A.M., Inc. is accredited by ...

  3. Hip replacement - precautions

    Science.gov (United States)

    ... page, please enable JavaScript. After you have hip replacement surgery, you will need to be careful how ... to Expect at Home After you have hip replacement surgery, you will need to be careful how ...

  4. 21 CFR 878.3530 - Silicone inflatable breast prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Silicone inflatable breast prosthesis. 878.3530... inflatable breast prosthesis. (a) Identification. A silicone inflatable breast prosthesis is a silicone... inflatable breast prosthesis that was in commercial distribution before May 28, 1976, or that has, on or...

  5. 21 CFR 878.3800 - External aesthetic restoration prosthesis.

    Science.gov (United States)

    2010-04-01

    ... an external prosthesis adhesive to fasten it to the body, the device is exempt from the current good... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External aesthetic restoration prosthesis. 878... External aesthetic restoration prosthesis. (a) Identification. An external aesthetic restoration prosthesis...

  6. The other hip in unilateral hip dysplasia

    DEFF Research Database (Denmark)

    Jacobsen, Steffen; Rømer, Lone; Søballe, Kjeld

    2006-01-01

    with apparently unilateral right developmental dysplasia (left hip center-edge angles greater than 20 degrees), 26 patients with apparently unilateral left developmental dysplasia (right hip center-edge angles greater than 20 degrees), 68 patients with bilateral developmental dysplasia, and 34 patients...... "gold" standard]). See the Guidelines for Authors for a complete description of levels of evidence....

  7. The Tribology of Explanted Hip Resurfacings Following Early Fracture of the Femur

    Directory of Open Access Journals (Sweden)

    James K. Lord

    2015-10-01

    Full Text Available A recognized issue related to metal-on-metal hip resurfacings is early fracture of the femur. Most theories regarding the cause of fracture relate to clinical factors but an engineering analysis of failed hip resurfacings has not previously been reported. The objective of this work was to determine the wear volumes and surface roughness values of a cohort of retrieved hip resurfacings which were removed due to early femoral fracture, infection and avascular necrosis (AVN. Nine resurfacing femoral heads were obtained following early fracture of the femur, a further five were retrieved due to infection and AVN. All fourteen were measured for volumetric wear using a co-ordinate measuring machine. Wear rates were then calculated and regions of the articulating surface were divided into “worn” and “unworn”. Roughness values in these regions were measured using a non-contacting profilometer. The mean time to fracture was 3.7 months compared with 44.4 months for retrieval due to infection and AVN. Average wear rates in the early fracture heads were 64 times greater than those in the infection and AVN retrievals. Given the high wear rates of the early fracture components, such wear may be linked to an increased risk of femoral neck fracture.

  8. Late Nontraumatic Dissociation of the Femoral Head and Trunnion in a Total Hip Arthroplasty

    Directory of Open Access Journals (Sweden)

    Simon J. M. Parker

    2015-01-01

    Full Text Available Background. Modular total hip arthroplasties are increasingly popular because customisation allows optimal restoration of patient biomechanics. However, the introduction of component interfaces provides greater opportunities for failure. We present a case of late nontraumatic dissociation of the head-neck interface, more than 10 years after insertion. Case Description. A 58-year-old woman had a left metal-on-metal total hip arthroplasty in 2002 for hip dysplasia. Following an uneventful 10-year period, she presented to hospital in severe pain after standing from a seated position, and radiographs demonstrated complete dissociation of the modular femoral head from the stem, with the femoral head remaining in its cup. There was no prior trauma or infection. Mild wear and metallosis were present on the articulating surface between the femoral head and trunnion. Soft tissues were unaffected. Discussion and Conclusions. This is the latest occurrence reported to date for nontraumatic component failure in such an implant by more than 7 years. The majority of cases occur in the context of dislocation and attempted closed reduction. We analyse and discuss possible mechanisms for failure, aiming to raise awareness of this potential complication and encouraging utmost care in component handling and insertion, as well as the long term follow-up of such patients.

  9. Surface and Subsurface Analyses of Metal-on-Polyethylene Total Hip Replacement Retrievals.

    Science.gov (United States)

    Vuong, Vicky; Pettersson, Maria; Persson, Cecilia; Larsson, Sune; Grandfield, Kathryn; Engqvist, Håkan

    2016-05-01

    Metal-on-polyethylene (MoP) articulations are one of the most reliable implanted hip prostheses. Unfortunately, long-term failure remains an obstacle to the service life. There is a lack of higher resolution research investigating the metallic surface component of MoP hip implants. This study investigates the surface and subsurface features of metallic cobalt chromium molybdenum alloy (CoCrMo) femoral head components from failed MoP retrievals. Unused prostheses were used for comparison to differentiate between wear-induced defects and imperfections incurred during implant manufacturing. The predominant scratch morphology observed on the non-implanted references was shallow and linear, whereas the scratches on the retrievals consisted of largely nonlinear, irregular scratches of varying depth (up to 150 nm in retrievals and up to 60 nm in reference samples). Characteristic hard phases were observed on the surface and subsurface material of the cast samples. Across all samples, a 100-400 nm thick nanocrystalline layer was visible in the immediate subsurface microstructure. Although observation of the nanocrystalline layer has been reported in metal-on-metal articulations, its presence in MoP retrievals and unimplanted prostheses has not been extensively examined. The results suggest that manufacturing-induced surface and subsurface microstructural features are present in MoP hip prostheses prior to implantation and naturally, these imperfections may influence the in vivo wear processes after implantation.

  10. HIPs at Ten

    Science.gov (United States)

    Kuh, George; O'Donnell, Ken; Schneider, Carol Geary

    2017-01-01

    2017 is the anniversary of the introduction of what are now commonly known as high-impact practices (HIPs). Many of the specific activities pursued under the HIPs acronym have been around in some form for decades, such as study abroad, internships, and student-faculty research. It was about ten years ago that, after conferring HIPs at Ten with…

  11. Bursitis of the Hip

    Science.gov (United States)

    ... difficile (C. diff.) InfectionHerpes Home Diseases and Conditions Bursitis of the Hip Condition Bursitis of the Hip Share Print Table of Contents1. ... Prevention5. Treatment6. Everyday Life7. Questions8. Resources What is bursitis of the hip? Bursitis is the painful swelling ...

  12. The Hip Restoration Algorithm

    Science.gov (United States)

    Stubbs, Allston Julius; Atilla, Halis Atil

    2016-01-01

    Summary Background Despite the rapid advancement of imaging and arthroscopic techniques about the hip joint, missed diagnoses are still common. As a deep joint and compared to the shoulder and knee joints, localization of hip symptoms is difficult. Hip pathology is not easily isolated and is often related to intra and extra-articular abnormalities. In light of these diagnostic challenges, we recommend an algorithmic approach to effectively diagnoses and treat hip pain. Methods In this review, hip pain is evaluated from diagnosis to treatment in a clear decision model. First we discuss emergency hip situations followed by the differentiation of intra and extra-articular causes of the hip pain. We differentiate the intra-articular hip as arthritic and non-arthritic and extra-articular pain as surrounding or remote tissue generated. Further, extra-articular hip pain is evaluated according to pain location. Finally we summarize the surgical treatment approach with an algorithmic diagram. Conclusion Diagnosis of hip pathology is difficult because the etiologies of pain may be various. An algorithmic approach to hip restoration from diagnosis to rehabilitation is crucial to successfully identify and manage hip pathologies. Level of evidence: V. PMID:28066734

  13. Successful staged hip replacement in septic hip osteoarthritis in osteopetrosis: a case report

    Directory of Open Access Journals (Sweden)

    Manzi Giovanni

    2012-04-01

    Full Text Available Abstract Background Osteopetrosis is a rare, inherited, bone disorder, characterized by osteosclerosis, obliteration of the medullary cavity and calcified cartilage. The autosomal dominant form is compatible with a normal life span, although fractures often result from minimal trauma, due to the pathologic nature of bone. Osteomyelitis is common in patients with osteopetrosis because of a reduced resistance to infection, attributed to the lack of marrow vascularity and impairment of white cell function. Only one case of osteomyelitis of the proximal third of the femur has been previously reported, treated with several repeated debridements and finally with femoral head resection. Here we present for the first time a case of a staged implant of a cementless total hip prosthesis for the treatment of a septic hip in femoral neck nonunion in osteopetrosis. Case presentation A 36-years-old woman, affected by autosomal dominant osteopetrosis was referred to our department because of a septic hip arthritis associated with femoral neck septic non-union, with draining fistulas. The infection occurred early after a plate osteosynthesis for a closed perthrocanteric fracture of the femur and persisted in spite of osteosynthesis removal, surgical debridement and external fixation. In our hospital the patient underwent accurate debridement, femoral head and greater trochanter resection, preparation of the diaphyseal intramedullary canal and implant of an antibiotic-loaded cement spacer. The spacer was exchanged after one month, due to infection recurrence and four months later, a cementless total hip arthroplasty was implanted, with no clinical and laboratory signs of infection recurrence at two years follow-up. Conclusions In case of hip septic arthritis and proximal femur septic non-union, femoral head resection may not be the only option available and staged total hip arthroplasty can be considered.

  14. [Prevention of prothesis dislocation after the revision of total hip arthroplasty].

    Science.gov (United States)

    Li, Yong-jiang; Zhang, Li-cheng; Yang, Guo-jing; Zhang, Chun-cai; Wang, Wei-liang; Lin, Rui-xin; Cai, Chun-yuan

    2008-03-01

    To explore the role of reconstruction of the posterior capsule and external rotators in prevention of postoperative dislocation in total hip arthroplasty revision following the posterolateral approach. Forty-five patients (47 hips) with the mean age of 65 years (55 to 78 years)of failed total hip arthroplasty were revised following the posterolateral approach. Posterior capsule was sutured to the anterosuperior portion of the capsule from where it had been detached, and the external rotators were then reattached to the soft tissue at the tip of the greater trochanter using 1.0 silk suture in surgery. The dislocation rate and risk factors were reviewed retrospectively to determine if closing the posterior capsule resulted in fewer dislocations. The femoral prosthesis and acetabular prosthesis were revised in 29 patients (31 hips), the liner was exchanged in 5 patients (5 hips), and the acetabular prosthesis or femoral components were revised in 10 patients (10 hips) and one patient (one hip) respectively. The procedure was the patient's first revision in 29 patients (30 hips), the second revision in 15 patients (16 hips), and the third revision in one patient(one hip). Radiographic evaluation included lower limb discrepancy, acetabular phase, femoral offset, anteversion angle, prosthetic loosening before and after revision. Function evaluation based on Harris score system. All patients were followed up with an average of 2.7 years. None of the patients sustained dislocation or infection, except one patient felt the anterior instability but without dislocation, X-ray revealed the acetabular component was in excessively anteversion. Lower leg discrepancy, acetabular abduction, anteversion femoral offest and collodiaphyseal angle were restored to normal level after operation on the basis of X-ray. One of the acetabular components and one of the femoral components were loose without dislocation. The Harris hip score improved from (49.13 +/- 15.53) points preoperatively

  15. Lower limb prosthesis utilisation by elderly amputees.

    Science.gov (United States)

    Bilodeau, S; Hébert, R; Desrosiers, J

    2000-08-01

    The goal of prosthetic rehabilitation is to compensate for the loss of a limb by amputation by, in the case of a lower limb, encouraging walking, and to achieve the same level of autonomy as prior to the amputation. However, because of difficulties walking, elderly amputees may use their prosthesis to a greater or lesser degree or simply stop using it during the rehabilitation period. The objective of this research was to study factors such as physical and mental health, rehabilitation, physical independence and satisfaction with the prosthesis to understand why amputees use their prosthesis or not. The sample was composed of 65 unilateral vascular amputees 60 years old or over living at home. The information was collected from medical records, by telephone interview and by mail questionnaire. Prosthesis use was measured by a questionnaire on amputee activities developed by Day (1981). Eighty-one per cent (81%) of the subjects wore their prosthesis every day and 89% of this group wore it 6 hours or more per day. Less use of the prosthesis was significantly related to age, female gender, possession of a wheelchair, level of physical disability, cognitive impairment, poorer self-perceived health and the amputee's dissatisfaction. A multiple regression analysis showed that satisfaction, not possessing a wheelchair and cognitive integrity explained 46% of the variance in prosthesis use.

  16. The type of surgical approach influences the risk of revision in total hip arthroplasty

    Science.gov (United States)

    2012-01-01

    Background and purpose The most common surgical approaches in total hip arthroplasty in Sweden are the posterior and the anterolateral transgluteal approach. Currently, however, there is insufficient evidence to prefer one over the other regarding risk of subsequent surgery. Patients and methods We searched the Swedish Hip Arthroplasty Register between the years 1992 and 2009 to compare the posterior and anterolateral transgluteal approach regarding risk of revision in the 3 most common all-cemented hip prosthesis designs in Sweden. 90,662 total hip replacements met the inclusion criteria. We used Cox regression analysis for estimation of prosthesis survival and relative risk of revision due to dislocation, infection, or aseptic loosening. Results Our results show that for the Lubinus SPII prosthesis and the Spectron EF Primary prosthesis, the anterolateral transgluteal approach gave an increased risk of revision due to aseptic loosening (relative risk (RR) = 1.3, 95% CI: 1.0–1.6 and RR = 1.6, CI: 1.0–2.5) but a reduced risk of revision due to dislocation (RR = 0.7, CI: 0.5–0.8 and RR = 0.3, CI: 0.1–0.4). For the Exeter Polished prosthesis, the surgical approach did not affect the outcome for dislocation or aseptic loosening. The surgical approach had no influence on the risk of revision due to infection in any of these designs. Interpretation This observational study shows that the surgical approach affected the risk of revision due to aseptic loosening and dislocation for 2 of the most commonly used cemented implants in Sweden. Further studies are needed to determine whether these results are generalizable to other implants and to uncemented fixation. PMID:23116440

  17. [APPLICATION OF DIGITAL PLANNING WITH BONE PARAMETERS IN DETERMINING OPTIMAL SIZE OF PROSTHESIS].

    Science.gov (United States)

    He, Jinpeng; Hao, Yun; Wang, Xiaolin; Shao, Jingfan; Yang, Xiaojin; Guo, Fengjing; Feng, Jiexiong

    2015-06-01

    To investigate the accuracy and value of digital planning with bone parameters in determining the appropriate prosthesis for total hip arthroplasty (THA). The preoperative radiographs was taken in 13 cases scheduled for THA between September 2012 and June 2013; the bone parameters were measured by digital template, and the prosthesis was selected and preoperative plan was made. There were 4 males and 9 females with an average age of 54.08 years (range, 41-79 years), including 8 left hips and 5 right hips. The causes were osteonecrosis of the femoral head in 8 cases and femoral neck fracture in 5 cases (3 cases had osteonecrosis of the femoral head). The operation time was 140-254 minutes (mean, 191.8 minutes). Two cases received blood transfusion, and 6 patients received plasma substitutes transfusion. There was no intraoperative fractures or postoperative thrombosis; atherosclerotic plaque occurred in 2 cases. Thirteen cases were followed up 12-24 months with an average of 17.3 months. The pain was relieved and limb function was improved in all patients. Harris score was significantly improved from preoperative 54.0 ± 12.9 to 91.1 ± 4.1 at 3 months after operation (t = 7.259, P = 0.000). Compared with the actual implants, the appropriate sizes of femoral stem was selected in 12 cases (92.31%) (excellent in 9 cases, good in 3 cases, and poor in 1 case), and the appropriate sizes of acetabular cup was selected in 11 cases (84.62%) (excellent in 7 cases, good in 4 cases, and poor in 2 cases). Digital planning could increase the accuracy in choosing the size of prosthesis for THA.

  18. Nasal prosthesis rehabilitation: a case report

    DEFF Research Database (Denmark)

    Jain, Sumeet; Maru, Kavita; Shukla, Jyotsana

    2011-01-01

    , often more effectively than by surgical reconstruction as the nose is relatively immobile structure. For successful results, lot of factors such as harmony, texture, color matching and blending of tissue interface with the prosthesis are important. The aim of the presented case report is to describe...... the non-surgical rehabilitation, with polymethyl meth-acrylate resin, nasal prosthesis for a patient who received partial rhinectomy as a result of squamous cell carcinoma of the nose. The prosthesis was made to restore the esthetic appearance of the patient with a mechanical retained design using...

  19. Stretch due to Penile Prosthesis Reservoir Migration

    Directory of Open Access Journals (Sweden)

    E. Baten

    2016-03-01

    Full Text Available A 43-year old patient presented to the emergency department with stretch, due to impossible deflation of the penile prosthesis, 4 years after successful implant. A CT-scan showed migration of the reservoir to the left rectus abdominis muscle. Refilling of the reservoir was inhibited by muscular compression, causing stretch. Removal and replacement of the reservoir was performed, after which the prosthesis was well-functioning again. Migration of the penile prosthesis reservoir is extremely rare but can cause several complications, such as stretch.

  20. [Implantation of bipolar prosthesis for treatment of medial femoral neck fractures in the elderly--clinical and radiographic outcome].

    Science.gov (United States)

    Müller, C A; Bayer, J; Szarzynski, E; Südkamp, N P

    2008-12-01

    In our study, we retrospectively evaluated 203 patients with medial or lateral femoral neck fractures who received 210 bipolar prosthesis (7 bilateral implantations) at our institution. 204 patients underwent cemented bipolar hemiarthroplasty. These included 149 females and 54 males with a median age of 82 (46-97) years. At the time of surgery 144 patients (71%) suffered from more than 3 medical conditions. We conducted our follow-up examination at a median of 27.9 months after the operation, at which time 97 patients (48%) had already died. On examination, 17% of our 76 patients had a Harris hip score between 90 and 100 and 20% between 80 and 89 or 70 and 79, respectively. 43% had a score of less than 70. In 20 patients (57%) we found radiographic evidence of periarticular ossification. Signs of loosening according to Gruen were found in 7 out of 35 patients, with no apparent clinical correlation. Surgery-related complications were noted in 15% of our 203 patients--mostly, with 10 cases each, wound infections and postoperative haematomas. In 3 cases of deep wound infection, a removal of the prosthesis was necessary, leading to a Girdlestone hip in one case. Postoperative hip dislocations occurred in 3.4% and intraoperative femur fissures were encountered in 1% of our patients. There were no cases of nerve damage or protrusion of the acetabulum reported. 43% of our patients developed a general complication--mainly cardiological or vascular problems, nephrological or urinary tract diseases, pulmonary or neurological complications. Hip arthroplasty is predominantly applied in older patients, most of them suffering from at least one medical condition at the time of surgery that influences their hospital course. This is why especially the overall physical condition of elderly patients has to be taken seriously into account when planning surgical treatment of femoral neck fractures. In our retrospective study, we have shown that implantation of a bipolar hip prosthesis

  1. Low revision rate after total hip arthroplasty in patients with pediatric hip diseases

    Science.gov (United States)

    2012-01-01

    Background The results of primary total hip arthroplasties (THAs) after pediatric hip diseases such as developmental dysplasia of the hip (DDH), slipped capital femoral epiphysis (SCFE), or Perthes’ disease have been reported to be inferior to the results after primary osteoarthritis of the hip (OA). Materials and methods We compared the survival of primary THAs performed during the period 1995–2009 due to previous DDH, SCFE, Perthes’ disease, or primary OA, using merged individual-based data from the Danish, Norwegian, and Swedish arthroplasty registers, called the Nordic Arthroplasty Register Association (NARA). Cox multiple regression, with adjustment for age, sex, and type of fixation of the prosthesis was used to calculate the survival of the prostheses and the relative revision risks. Results 370,630 primary THAs were reported to these national registers for 1995–2009. Of these, 14,403 THAs (3.9%) were operated due to pediatric hip diseases (3.1% for Denmark, 8.8% for Norway, and 1.9% for Sweden) and 288,435 THAs (77.8%) were operated due to OA. Unadjusted 10-year Kaplan-Meier survival of THAs after pediatric hip diseases (94.7% survival) was inferior to that after OA (96.6% survival). Consequently, an increased risk of revision for hips with a previous pediatric hip disease was seen (risk ratio (RR) 1.4, 95% CI: 1.3–1.5). However, after adjustment for differences in sex and age of the patients, and in fixation of the prostheses, no difference in survival was found (93.6% after pediatric hip diseases and 93.8% after OA) (RR 1.0, CI: 1.0–1.1). Nevertheless, during the first 6 postoperative months more revisions were reported for THAs secondary to pediatric hip diseases (RR 1.2, CI: 1.0–1.5), mainly due to there being more revisions for dislocations (RR 1.8, CI: 1.4–2.3). Comparison between the different diagnosis groups showed that the overall risk of revision after DDH was higher than after OA (RR 1.1, CI: 1.0–1.2), whereas the combined

  2. Influence of demographic, surgical and implant variables on wear rate and osteolysis in ABG I hip arthroplasty

    Czech Academy of Sciences Publication Activity Database

    Gallo, J.; Havránek, Vítězslav; Čechová, I.; Zapletalová, J.

    2006-01-01

    Roč. 150, č. 1 (2006), s. 135-141 ISSN 1213-8118 R&D Projects: GA MŠk(CZ) 1M06002 Institutional research plan: CEZ:AV0Z10100522 Keywords : total hip arthroplasty * ABG I prosthesis * wear rate * polyethylene Subject RIV: EI - Biotechnology ; Bionics

  3. Results of revision of hip arthroplasty with cement. A five to fourteen-year follow-up study

    NARCIS (Netherlands)

    Marti, R. K.; Schüller, H. M.; Besselaar, P. P.; Vanfrank Haasnoot, E. L.

    1990-01-01

    We reviewed the results of sixty revisions of cemented total hip replacement in fifty-four patients who had complete clinical and radiographic follow-up. All of the revisions were performed by a standardized operative technique, in which both components of a single model of prosthesis were fixed

  4. Clinical and radiological mid-term results of the thrust plate prosthesis

    OpenAIRE

    Steens, W.; v.d. Daele, R.; Simon, U.; Goetze, C.

    2009-01-01

    The purpose of this study was to perform an objective clinical and radiological assessment of the thrust plate prosthesis (TPP). Fifty-three prostheses were evaluated clinically using the Harris hip score (HHS), visual analog scale (VAS), and radiographically before surgery, at the time of discharge, and postoperatively after on average of 8.09 (range 4.61–9.93) years. The average HHS significantly (p ≤ 0.05) improved from 48 (range 18–77) points to 95 (range 46–100) points. The VAS revealed ...

  5. Revision Total Hip Arthroplasty Complicated by Metastatic Malignant Gastrointestinal Stromal Tumour

    Directory of Open Access Journals (Sweden)

    Hok-Yin Alwin Li

    2014-06-01

    Full Text Available Periprosthetic malignancy causing failure of total hip arthroplasty is a rare entity. Metastasis of malignant tumour to the proximity of orthopaedic implants is even more uncommon. We present a case of a 74-year-old female with an infected Austin Moore prosthesis, requiring a two-stage revision total hip arthroplasty. Within 2 years postoperatively, erosion of the lesser trochanter was noted. Further revision surgery was performed with the insertion of a cement spacer. Despite the expectation of an infected prosthesis, intraoperative frozen section showed sarcoma and the final pathology was metastasis of a recurrent gastrointestinal stromal tumour (GIST. Metastatic GIST to total hip prosthesis had not been reported previously and this case illustrates how intraoperative frozen section can aid diagnosis and management. We also highlighted some diagnostic clues, differentiating this rare diagnosis from septic loosening and osteolysis. Malignant infiltration should be considered as a differential diagnosis in failed total hip arthroplasty, especially in patients with a previous history of malignancy.

  6. Finger prosthesis: a boon to handicapped.

    Science.gov (United States)

    Gupta, Ridhima; Kumar, Lakshya; Rao, Jitendra; Singh, Kamleshwar

    2013-08-29

    This is a clinical case report of a 52-year-old male patient with four partially missing fingers of the left hand. The article describes the clinical and laboratory procedure of making prosthesis with modern silicone material. A wax pattern was fabricated using the right hand of the patient. A special type of wax was formulated to make the pattern so that it can be easily moulded and carved. Intrinsic and extrinsic staining was also performed to match the adjacent skin colour. The patient was given the finger prosthesis and was asked to use a half glove (sports) to mask the junction between the prosthesis and the normal tissue. It also provides additional retention to the artificial fingers. The patient felt his social acceptance improved after wearing the finger prosthesis.

  7. Clinical and radiographical results of 179 thrust plate hip prostheses: 5-14 years follow-up study.

    Science.gov (United States)

    Yasunaga, Yuji; Yamasaki, Takuma; Matsuo, Toshihiko; Yoshida, Tomokazu; Oshima, Seigo; Hori, Junji; Yamasaki, Keiichiro; Ochi, Mitsuo

    2012-04-01

    The thrust plate hip prosthesis (TPP) is a bone-reserving prosthesis for cementless fixation at the metaphysis of the proximal femur. We retrospectively evaluated the results of 162 patients (179 hips) who underwent hip arthroplasty using TPP. Eighty-three patients (87 hips) suffered from osteoarthritis of the hip joint (OA group), 79 patients (92 hips) from osteonecrosis of the femoral head (ON group). The mean age at surgery was 55 years in the OA group and 47.4 years in the ON group. The mean follow-up period was 97 months in the OA group and 104 months in the ON group. For these patients, we evaluated the results clinically and radiographically. The mean Merle d'Aubigne's score improved from 8.2 to 16.9 in the OA group and from 9.1 to 16.6 in the ON group at the final follow-up. Early mechanical loosening of TPP was observed in two hips of OA and one hip of ON. In one patient of ON, bilateral TPPs had to be removed 5 years postoperatively because of infection. Two female patients with ON suffered from a spontaneous femoral fracture below the tip of the lateral plate. Kaplan-Meier survivorship using TPP removed for any reason as the end point was 97.7% in the OA group and 90.3% in the ON group after 13 years. The middle-term results of the TPP were satisfactory if the indication for the TPP and the operative procedure were appropriate. The TPP is a useful and safe prosthesis for relatively young patients with not only osteoarthritis of the hip but also osteonecrosis of the femoral head.

  8. Stiffness Analysis of Above Knee Prosthesis

    OpenAIRE

    Ege, Mücahit; Küçük, Serdar

    2016-01-01

    While a healthy human walks, his or her legs mutually perform good repeatabilitywith high accuracy. This provides an esthetical movement and balance. Peoplewith above knee prosthesis want to perform walking as esthetical as a healthyhuman. Therefore, to achieve a healthy walking, the above knee prosthesis mustprovide a good stiffness performance. Especially stiffness values are requiredwhen adding a second axis movement to the ankle for eversion and inversion. Inthis paper, stiffness analysis...

  9. Hip Resurfacing: An Alternative to Conventional Hip Replacement?

    Science.gov (United States)

    ... Is hip resurfacing a good alternative to hip replacement? Answers from Mark Spangehl, M.D. Hip resurfacing has lost favor with many surgeons ... women with poor bone quality. Unlike traditional hip replacement, hip resurfacing doesn't completely replace the "ball" ...

  10. [Treatment of periprosthetic femoral fractures after total hip arthroplasty with specially constructed retrograde hollow nails].

    Science.gov (United States)

    Szalay, G; Meyer, C; Mika, J; Schnettler, R; Thormann, U

    2014-12-01

    Treatment of periprosthetic fractures by implantation of a specially constructed, retrograde hollow nail which fits over the tip of the prosthesis and becomes locked on it. Periprosthetic femoral fractures with firmly anchored prosthesis shaft after total hip arthroplasty of types B1 and C according to the Vancouver classification. Loosened prosthesis (type B2/B3) and trochanteric fractures (type A). Broken or damaged prosthesis, florid inflammation and soft tissue injuries in the operation field, contracted knee joint, advanced deformation in the knee joint and distal femur, enclosed prosthesis and general contraindications. In a supine position the periprosthetic fracture is exposed via a lateral access. For cemented prostheses the cement is removed around the tip of the prosthesis (at least 2-3 cm) and medullary cavity. Arthrotomy with flexion of the knee joint and marking of the nail entry point. Drill the medullary cavity, retrograde introduction of the nail, visually fit the nail over the tip of the prosthesis and lock the nail with the prosthesis. If necessary use additional spongiosaplasty or also placement of additional cerclages depending on fracture type and size of the defect zone. Lock the nail distally. Use intraoperative radiological imaging to control correct positioning and length of the nail. Close the wound layer by layer with placement of suction drainage devices and dressing. Partial loading for 6 weeks with a subsequent pain-adapted loading gradient until full loading is possible. If selective partial loading is not possible, a decision must be made in individual cases as to whether the intraoperative findings allow immediate full loading. From 2004 to 2011 a total of 25 periprosthetic femoral fractures in 25 patients were treated in 2 locations using specially constructed slotted hollow nails. Within the framework of a retrospective study 20 of these patients (16 female and 4 male; average age 77.2 [72-84] years) were clinically and

  11. The increase in cobalt release in metal-on-polyethylene hip bearings in tests with third body abrasives.

    Science.gov (United States)

    de Villiers, Danielle; Traynor, Alison; Collins, Simon N; Shelton, Julia C

    2015-09-01

    Hypersensitivity reactions in patients receiving metal-on-metal hip replacements have been attributed to corrosion products as observed by elevated cobalt and chromium ions in the blood. Although the majority of cases are reported in metal-on-metal, incidences of these reactions have been reported in the metal-on-polyethylene patient population. To date, no in vitro study has considered cobalt release for this bearing combination. This study considered four 28 mm and seven 52 mm diameter metal-on-polyethylene bearings tested following ISO standard hip simulator conditions as well as under established abrasive conditions. These tests showed measurable cobalt in all bearings under standard conditions. Cobalt release, as well as polyethylene wear, increased with diameter, increasing from 52 to 255 ppb. The introduction of bone cement particles into the articulation doubled polyethylene wear and cobalt release while alumina particles produced significant damage on the heads demonstrated by cobalt levels of 70,700 ppb and an increased polyethylene wear from a mean value of 9-160 mm(3)/mc. Cobalt release was indicative of head damage and correlated with polyethylene wear at the next gravimetric interval. The removal of third body particles resulted in continued elevated cobalt levels in the 52 mm diameter bearings tested with alumina compared to standard conditions but the bearings tested with bone cement particles returned to standard levels. The polyethylene wear in the bone cement tested bearings also recovered to standard levels, although the alumina tested bearings continued to wear at a higher rate of 475 mm(3)/mc. Cobalt release was shown to occur in metal-on-polyethylene bearings indicating damage to the metal head resulting in increased polyethylene wear. While large diameter metal-on-polyethylene bearings may provide an increased range of motion and a reduced dislocation risk, increased levels of cobalt are likely to be released and this needs to be fully

  12. Clinical and radiological mid-term results of the thrust plate prosthesis.

    Science.gov (United States)

    Steens, W; v d Daele, R; Simon, U; Goetze, C

    2009-12-01

    The purpose of this study was to perform an objective clinical and radiological assessment of the thrust plate prosthesis (TPP). Fifty-three prostheses were evaluated clinically using the Harris hip score (HHS), visual analog scale (VAS), and radiographically before surgery, at the time of discharge, and postoperatively after on average of 8.09 (range 4.61-9.93) years. The average HHS significantly (p thrust plate. Sixteen prostheses revealed signs of radiolucent zones. In general, there was a good clinical outcome with no major limitations in function. Radiographic changes under the thrust plate indicate an adaptation processes resulting from changed biomechanics. This study suggests that the TPP could be a good alternative in total hip replacement in younger patients.

  13. Carbon-carbon composites for orthopedic prosthesis and implants. CRADA final report

    Energy Technology Data Exchange (ETDEWEB)

    Burchell, T D; Klett, J W; Strizak, J P [Oak Ridge National Lab., TN (United States); Baker, C [FMI, Biddeford, ME (United States)

    1998-01-21

    The prosthetic implant market is extensive. For example, because of arthritic degeneration of hip and knee cartilage and osteoporotic fractures of the hip, over 200,000 total joint replacements (TJRs) are performed in the United States each year. Current TJR devices are typically metallic (stainless steel, cobalt, or titanium alloy) and are fixed in the bone with polymethylacrylate (PMMA) cement. Carbon-carbon composite materials offer several distinct advantages over metals for TJR prosthesis. Their mechanical properties can be tailored to match more closely the mechanical properties of human bone, and the composite may have up to 25% porosity, the size and distribution of which may be controlled through processing. The porous nature of carbon-carbon composites will allow for the ingrowth of bone, achieving biological fixation, and eliminating the need for PMMA cement fixation.

  14. [Thrombosis of the superficial femoral vein due to psoas bursitis secondary to particle disease in total hip arthroplasty].

    Science.gov (United States)

    Lax-Pérez, R; Salinas-Gilabert, J E; Lajara-Marco, F; Lax-Pérez, A; Corraliza-Zamorano, A; García-Gálvez, A; Izquierdo-Plazas, L

    2011-01-01

    The case of a male 76 year-old patient with a history of total hip replacement surgery is presented herein. The patient had tumors in the iliac fossa with swelling of the thigh and pain upon hip flexion and extension. The complementary ultrasound and computed tomography show a large lobed cystic tumor in the left iliac fossa, 7 cm in diameter, close to the prosthesis. The diagnosis was psoas bursitis secondary to the release of polyethylene particles that caused compression and thrombosis of the superficial femoral vein. Cyst formation caused by polyethylene disease after total hip arthroplasty is infrequent.

  15. [Superficial femoral vein thrombosis due to large psoas bursitis secondary to particle disease in total hip arthroplasty].

    Science.gov (United States)

    Lax-Pérez, R; Salinas-Gilabert, J E; Lajara-Marco, F; Lax-Pérez, A; Corraliza-Zamorano, A; García-Gálvez, A; Izquierdo-Plazas, L

    2012-01-01

    Male, 76 year-old patient with a history of total hip arthroplasty who presents with a mass in the iliac fossa with swelling of the thigh and hip pain upon flexion and extension. Complementary ultrasound and computed tomography scan studies show a giant lobulated cystic mass in the left iliac fossa, 7 cm in diameter, near the prosthesis. Cyst formation caused by polyethylene disease after total hip arthroplasty is infrequent. We present a case of large psoas bursitis secondary to the release of polyethylene particles which caused superficial femoral vein compression and thrombosis.

  16. [Clinical observation of 15° face-changing acetabular cup in total hip replacement for the treatment of developmental dysplasia of hip].

    Science.gov (United States)

    Hou, Wei-kun; Liu, Lin; Lu, Chao; Peng, Kan; Yang, Zhi; Xu, Ke; Xu, Peng

    2016-06-01

    To explore early clinical effect of acetabular cup in total hip replacement for the treatment of Crowe II developmental dysplasia of hip. Eighteen patients (18 hips) with Crowe type II developmental dysplasia of hip were treated with total hip replacement from September 2001 to July 2013. Among them,including 13 males and 5 females aged from 42 to 60 years old with an average of 47.6 years old; the courses of diseases ranged from 9 to 22 years with an average of 13.5 years. All the patients had hip joint pain, limb shortening and limited hip function before operation. Harris score of hip joint were used to evaluate recovery of function at 1 day and 12 months after operation. Prosthetic coverage of acetabular cup at 1 week after operation was observed by using radiography. Eighteen patients (18 hips) were followed up from 12 to 24 months with an average 17 months. All incisions were healed at stage I. No deep vein thrombosis, hip dislocation, periprosthetic joint infection and prosthesis loosening were occurred. No revision surgery during follow-up period. Prosthetic coverage of acetabular cup was more than 80% at 1 week after operation. Harris score were increased from 42.67 ± 5.06 before operation to 94.79 ± 3.27 at 12 months after operation (t = -45.269, P developmental dysplasia of hip patients, 15° face-changing acetabular cups in THR could obtain higher actebular component coverage rate and satisfactory early clinical effects.

  17. Different techniques in fabrication of ocular prosthesis.

    Science.gov (United States)

    Cevik, Pinar; Dilber, Erhan; Eraslan, Oguz

    2012-11-01

    Loss of an eye caused by cancer, trauma, or congenital defect creates a deep psychological impact on an individual's life especially social and professional life. Custom-made prosthesis, compared to stock prosthesis, provides a better fit to the eye socket, better cosmetic results, and less discomfort to the patient in the long term. The main objective of this article was to describe 3 different alternative and practical techniques of fabricating custom-made ocular prosthesis. An impression of anophthalmic socket was made with the addition of cured silicone-based precision impression material in all techniques. A master cast was prepared and duplicated with condensation silicone. A self-cure acrylic resin was polymerized in the silicone model and was fitted into the patient's eye socket. A digital photograph of the patient's iris was made using a digital camera and printed on good-quality photo paper in various shades and sizes in the first and the second techniques. Then the photo paper was coated with PVC so as not to allow any color flowing. The proper iris was then inserted to the acrylic base. The prosthesis was final processed using orthodontic heat polymerizing clear acrylic resin.In the other technique, after the trying-in process with wax pattern, an acrylic base was fabricated using heat polymerizing scleral acrylic resin. The prosthetic iris was fabricated from a transparent contact lens by painting the lens with watercolor paints and attaching it to an acrylic resin with tissue conditioner. The final process was made with heat polymerizing transparent acrylic resin. Custom-made prosthesis allows better esthetic and functional results to the patient in comparison to stock prosthesis. Further follow-up is necessary to check the condition and fit of the ocular prosthesis in such patients.

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

    Directory of Open Access Journals (Sweden)

    Gholam Hossein Shahcheraghi

    2015-09-01

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

  19. Developmental dysplasia of the hip

    Science.gov (United States)

    ... dislocation of the hip joint; Developmental hip dysplasia; DDH; Congenital dysplasia of the hip; Congenital dislocation of ... during pregnancy can increase a baby's risk of DDH. Other risk factors include: Being the first child ...

  20. [Metacarpophalangeal prosthesis modeling. Comparison of stress factors in a normal and a prosthetic metacarpophalangeal joint using finite element analysis].

    Science.gov (United States)

    Gayet, L E; Texereau, J; Dumas, S

    2000-07-01

    Prosthetic replacement of the metacarpophalangeal joints of long fingers is a problematical technique for the surgeon. The aim of the present study was to examine and compare, by means of finite element analysis, stress distribution in a normal metacarpophalangeal joint and to compare this with the findings in a similar joint with a prosthesis in order to better determine the risk of aseptic loosening, and also to examine possible solutions to limit these risks. Finite element modelling was carried out using Abaqus software. Various criteria were taken into account including anatomical data, stress distribution, mechanical characteristics of the materials used, and different positions of the phalanx. A comparison of the results showed two significant stress distribution factors, i.e., a reduction of normal stress in the cortical bone of the finger fitted with a prosthesis; and the appearance of a flexion moment which completely modified the stress distribution throughout the metacarpal and therefore also in the opposite phalanx. To reduce the risk of aseptic loosening, two solutions were proposed: a) to reduce Young's module. The problem which arises, as in the case of total hip prosthesis, is that of finding a material with a Young's module which is closer to that of cortical bone, and which at the same time has a high elastic limit and breakage point and good biocompatibility; b) to reduce the inertia of the prosthesis, which seems the more likely of the two propositions, as it is based on the results of the modelling. The inertia of the prosthesis on stress distribution can be reduced by modifying two parameters, namely by producing a hollow section and shortening the structure of the prosthesis.

  1. Total Hip Arthroplasty Using a Polished Tapered Cemented Stem in Hereditary Multiple Exostosis

    Directory of Open Access Journals (Sweden)

    Akio Kanda

    2016-01-01

    Full Text Available A 61-year-old Japanese man underwent right total hip arthroplasty for hereditary multiple exostosis. At first presentation, he had suffered from coxalgia for a long time. On radiographic images, there was a gigantic femoral head, increased shaft angle, and large diameter of the femoral neck. He had also developed coxarthrosis and severe pain of the hip joint. The transformation of the proximal femur bone causes difficulty in setting a cementless total hip prosthesis. Therefore, total hip arthroplasty using a cemented polished tapered stem was performed via a direct lateral approach. Using a cemented polished tapered stem allowed us to deal with the femoral bone transformation and bone substance defectiveness due to exostosis and also minimized the invasiveness of the operation.

  2. Factors that predict walking ability with a prosthesis in lower limb amputees

    Directory of Open Access Journals (Sweden)

    Knežević Aleksandar

    2016-01-01

    Full Text Available Introduction. Identification of predictive factors for walking ability with a prosthesis, after lower limb amputation, is very important in order to define patient’s potentials and realistic rehabilitation goals, however challenging they are. Objective. The objective of this study was to investigate whether variables determined at the beginning of rehabilitation process are able to predict walking ability at the end of the treatment using support vector machines (SVMs. Methods. This research was designed as a retrospective clinical case series. The outcome was defined as three-leveled ambulation ability. SVMs were used for predicting model forming. Results. The study included 263 patients, average age 60.82 Ѓ} 9.27 years. In creating SVM models, eleven variables were included: age, gender, cause of amputation, amputation level, period from amputation to prosthetic rehabilitation, Functional Comorbidity Index (FCI, presence of diabetes, presence of a partner, restriction concerning hip or knee extension, residual limb hip extensor strength, and mobility at admission. Six SVM models were created with four, five, six, eight, 10, and 11 variables, respectively. Genetic algorithm was used as an optimization procedure in order to select the best variables for predicting the level of walking ability. The accuracy of these models ranged from 72.5% to 82.5%. Conclusion. By using SVM model with four variables (age, FCI, level of amputation, and mobility at admission we are able to predict the level of ambulation with a prosthesis in lower limb amputees with high accuracy.

  3. Hard-on-hard lubrication in the artificial hip under dynamic loading conditions.

    Directory of Open Access Journals (Sweden)

    Robert Sonntag

    Full Text Available The tribological performance of an artificial hip joint has a particularly strong influence on its success. The principle causes for failure are adverse short- and long-term reactions to wear debris and high frictional torque in the case of poor lubrication that may cause loosening of the implant. Therefore, using experimental and theoretical approaches models have been developed to evaluate lubrication under standardized conditions. A steady-state numerical model has been extended with dynamic experimental data for hard-on-hard bearings used in total hip replacements to verify the tribological relevance of the ISO 14242-1 gait cycle in comparison to experimental data from the Orthoload database and instrumented gait analysis for three additional loading conditions: normal walking, climbing stairs and descending stairs. Ceramic-on-ceramic bearing partners show superior lubrication potential compared to hard-on-hard bearings that work with at least one articulating metal component. Lubrication regimes during the investigated activities are shown to strongly depend on the kinematics and loading conditions. The outcome from the ISO gait is not fully confirmed by the normal walking data and more challenging conditions show evidence of inferior lubrication. These findings may help to explain the differences between the in vitro predictions using the ISO gait cycle and the clinical outcome of some hard-on-hard bearings, e.g., using metal-on-metal.

  4. Hard-on-hard lubrication in the artificial hip under dynamic loading conditions.

    Science.gov (United States)

    Sonntag, Robert; Reinders, Jörn; Rieger, Johannes S; Heitzmann, Daniel W W; Kretzer, J Philippe

    2013-01-01

    The tribological performance of an artificial hip joint has a particularly strong influence on its success. The principle causes for failure are adverse short- and long-term reactions to wear debris and high frictional torque in the case of poor lubrication that may cause loosening of the implant. Therefore, using experimental and theoretical approaches models have been developed to evaluate lubrication under standardized conditions. A steady-state numerical model has been extended with dynamic experimental data for hard-on-hard bearings used in total hip replacements to verify the tribological relevance of the ISO 14242-1 gait cycle in comparison to experimental data from the Orthoload database and instrumented gait analysis for three additional loading conditions: normal walking, climbing stairs and descending stairs. Ceramic-on-ceramic bearing partners show superior lubrication potential compared to hard-on-hard bearings that work with at least one articulating metal component. Lubrication regimes during the investigated activities are shown to strongly depend on the kinematics and loading conditions. The outcome from the ISO gait is not fully confirmed by the normal walking data and more challenging conditions show evidence of inferior lubrication. These findings may help to explain the differences between the in vitro predictions using the ISO gait cycle and the clinical outcome of some hard-on-hard bearings, e.g., using metal-on-metal.

  5. Experimental Recognition of Loading Character of Transtibial Prosthesis

    Czech Academy of Sciences Publication Activity Database

    Paloušek, D.; Návrat, Tomáš; Rosický, J.; Krejčí, Petr; Houfek, Martin

    2008-01-01

    Roč. 15, č. 5 (2008), s. 355-364 ISSN 1802-1484 Institutional research plan: CEZ:AV0Z20760514 Keywords : transtibial prosthesis * strain gauge * loading character of prosthesis Subject RIV: BO - Biophysics

  6. Ultrasound mammography in prosthesis-related breast augmentation complications

    NARCIS (Netherlands)

    van Wingerden, J. J.; van Staden, M. M.

    1989-01-01

    Ultrasound mammography is presented as a safe, simple, and reliable method of assessing prosthesis and prosthesis-related complications in the augmented breast. The ability to distinguish between silicone gel, muscle, hematoma, and fluid collections has made ultrasound mammography especially

  7. 21 CFR 872.3950 - Glenoid fossa prosthesis.

    Science.gov (United States)

    2010-04-01

    ...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3950 Glenoid fossa prosthesis. (a) Identification. A glenoid fossa prosthesis is a device that is intended to be implanted in the temporomandibular...

  8. [Gluteal compartment syndrome after total hip replacement. A presentation of two cases].

    Science.gov (United States)

    Villalba, J; Solernou, X

    2013-01-01

    Many postoperative complications have been described after a total hip arthroplasty, with early and acute, as well as late, complications being reported. Two cases of compartment syndrome of the buttock are described following a hybrid total hip arthroplasty (cemented stem and press-fit and screwed acetabulum) performed on 2 patients of 60 and 68 years old, both diagnosed and treated 24-48 hours after the surgery. Both cases had a primary prosthesis with no previous significant pathological findings. This condition is still rare, and few cases have been described at the medical literature. Copyright © 2012 SECOT. Published by Elsevier Espana. All rights reserved.

  9. The Use of PROSTALAC in Two-stage Reimplantation of Septic Total Knee and Hip Arthroplasty

    Directory of Open Access Journals (Sweden)

    BL Wam

    2010-11-01

    Full Text Available The PROSTALAC (PROSThesis Antibiotic Loaded Acrylic Cement functional spacer is made with antibiotic-loaded acrylic cement. We use it as an interim spacer in two-stage exchange arthroplasty in cases of infected total knee or total hip replacement. PROSTALAC allows continuous rehabilitation between stages as it maintains good alignment and stability of the joint with a reasonable range of movement. It also helps to maintain the soft-tissue planes, thereby facilitating the second-stage procedure. We report here early outcomes of the use of PROSTALAC in 5 patients - 3 in total knee replacements, 1 in a total hip replacement and 1 in a bipolar hemiarthroplasty.

  10. Dissociation of bipolar prostheses with hip subluxation: A case report and literature review

    Directory of Open Access Journals (Sweden)

    Jung-Jui Chang

    2014-01-01

    Full Text Available Bipolar hemiarthroplasty, a modular system, has been utilized for decades to treat intracapsular fractures of the femoral neck and avascular necrosis of the femoral head. Dislocation is one of the main complications of hip hemiarthroplasty performed for displaced femoral neck fractures. Classic dislocation of the hemiarthroplasty from the native acetabulum occurs in 2.6% of cases. Dissociation between the small head of the prosthesis and the polyethylene insert is an extremely rare complication of bipolar hemiarthroplasty and results in hip dislocation and severe disability. Surgeons must be cognizant of this rare complication and should proceed to open reduction to treat this problem.

  11. An experimental-numerical method for comparative analysis of joint prosthesis; Un metodo numerico-experimental para el analisis comparativo de protesis articulares

    Energy Technology Data Exchange (ETDEWEB)

    Claramunt, R.; Rincon, E.; Zubizarreta, V.; Ros, A.

    2001-07-01

    The difficulty that exists in the analysis of mechanical stresses in bones is high due to its complex mechanical and morphological characteristics. This complexity makes generalists modelling and conclusions derived from prototype tests very questionable. In this article a relatively simple comparative analysis systematic method that allow us to establish some behaviour differences in different kind of prosthesis is presented. The method, applicable in principle to any joint problem, is based on analysing perturbations produced in natural stress states of a bone after insertion of a joint prosthesis and combines numerical analysis using a 3-D finite element model and experimental studies based on photoelastic coating and electric extensometry. The experimental method is applied to compare two total hip prosthesis cement-free femoral stems of different philosophy. One anatomic of new generation, being of oblique setting over cancellous bone and the other madreporique of trochantero-diaphyseal support over cortical bone. (Author) 4 refs.

  12. Medium-term results of hip arthroplasty with ASR XL (DePuy

    Directory of Open Access Journals (Sweden)

    V. V. Danilyak

    2015-01-01

    Full Text Available The purpose - to identify factors affect on instability and to access the medium-term survivorship of metal-on-metal X-large heads total hip prostheses. Material and methods. From January 2007 March 2009 we performed 134 ASR XL head - Corail total hip arthroplasties in 119 patients. The medium-term results were studied in 94 (105 hips. Mean follow-up was 76±3 months. Radiological evaluation was carried out in standard views. Clinical and functional results were accessed with Harris Hip Score. We determined metal ions concentration in whole blood with atomic absorption spectrometry (AAS and mass spectrometry in the induced coupled plasma (ICP-MS. Changes in periprosthetic tissues were studied at high field magnetic resonance imaging (MRI with subsequent histological confirmation. “Gamma test” was applied for statistic analysis revision risk factors. Results. Medium-term survivorship of studied implants amounted to 85.5% (95% CI 78.7% to 92.3%. Average ions concentration in the whole blood of amounted to 3.2 ppb and 2.9 ppb foe Co and Cr respectively Specific risk factors of instability were gender (female, small size of the cups, and high angle of abduction (>45°. The main reason for revision was cup loosening (over 50%. Conclusions. Patients in this cohort are in a great danger of early aseptic loosening, especially in the presence of specific risk factors. So the annual monitoring is considered mandatory for them. The indications for revision surgery are not only the evident implant instability, but also the pathological changes in periprosthetic tissues associated with high ions level in whole blood.

  13. Hip fracture surgery

    Science.gov (United States)

    ... allows your surgeon to use an x-ray machine to see how well the parts of your hip bone line up. The surgeon ... allows your surgeon to use an x-ray machine to see how well the parts of your hip bone line up. The surgeon ...

  14. TREATMENT OF HIP DYSPLASIA

    Directory of Open Access Journals (Sweden)

    Iulian ICLEANU

    2015-11-01

    Full Text Available In this thesis, our purpose is to show that using physiotherapy on patients with hip dysplasia from the very beginning, in the first months of life, helps treating them faster. Common literature proposes to use physiotherapy on patients with hip dysplasia either after their recovery or in the terminal phase of recovery, claiming that any earlier intervention will prolong the hip recovery. The effects of hip dysplasia reflect over the whole musculoskeletal system, while it hinders the knees (genu valgum, the ankles (ankle valgus, calcaneal valgus and the spine (scoliosis especially at the lumbar level. The most spectacular are at the hip level, that is why we made an analytical evaluation only for this joint. To show the importance of physiotherapy for children with hip dysplasia we started from the hypothesis: untimely treatment for children with hip dysplasia has improved results in functional recovery and in obtaining a better stability, without the necessity of orthopedics or surgical interventions. The research methods used in this study are: the observation method, the bibliographic study method, the experimental method, the graphics method and the statistical mathematical method to process the data and to represent the results graphically. In the end, the results obtained are significantly different from the initial evaluations and we came to the conclusion that starting an untimely analytical kinetic treatment and globally personalizing it to every patient improves stability and biomechanical parameters for the hip.

  15. Reverse hybrid total hip arthroplasty

    Science.gov (United States)

    Wangen, Helge; Havelin, Leif I; Fenstad, Anne M; Hallan, Geir; Furnes, Ove; Pedersen, Alma B; Overgaard, Søren; Kärrholm, Johan; Garellick, Göran; Mäkelä, Keijo; Eskelinen, Antti; Nordsletten, Lars

    2017-01-01

    Background and purpose The use of a cemented cup together with an uncemented stem in total hip arthroplasty (THA) has become popular in Norway and Sweden during the last decade. The results of this prosthetic concept, reverse hybrid THA, have been sparsely described. The Nordic Arthroplasty Register Association (NARA) has already published 2 papers describing results of reverse hybrid THAs in different age groups. Based on data collected over 2 additional years, we wanted to perform in depth analyses of not only the reverse hybrid concept but also of the different cup/stem combinations used. Patients and methods From the NARA, we extracted data on reverse hybrid THAs from January 1, 2000 until December 31, 2013. 38,415 such hips were studied and compared with cemented THAs. The Kaplan-Meier method and Cox regression analyses were used to estimate the prosthesis survival and the relative risk of revision. The main endpoint was revision for any reason. We also performed specific analyses regarding the different reasons for revision and analyses regarding the cup/stem combinations used in more than 500 cases. Results We found a higher rate of revision for reverse hybrids than for cemented THAs, with an adjusted relative risk of revision (RR) of 1.4 (95% CI: 1.3–1.5). At 10 years, the survival rate was 94% (CI: 94–95) for cemented THAs and 92% (95% CI: 92–93) for reverse hybrids. The results for the reverse hybrid THAs were inferior to those for cemented THAs in patients aged 55 years or more (RR =1.1, CI: 1.0–1.3; p revision due to periprosthetic femoral fracture for reverse hybrids than for cemented THAs in patients aged 55 years or more (RR =3.1, CI: 2.2–4.5; p revision than cemented THAs in patients aged 55 or more. The difference in survival was mainly caused by a higher incidence of early revision due to periprosthetic femoral fracture in the reversed hybrid THAs. PMID:28095724

  16. Robotic lower limb prosthesis design through simultaneous computer optimizations of human and prosthesis costs

    Science.gov (United States)

    Handford, Matthew L.; Srinivasan, Manoj

    2016-02-01

    Robotic lower limb prostheses can improve the quality of life for amputees. Development of such devices, currently dominated by long prototyping periods, could be sped up by predictive simulations. In contrast to some amputee simulations which track experimentally determined non-amputee walking kinematics, here, we explicitly model the human-prosthesis interaction to produce a prediction of the user’s walking kinematics. We obtain simulations of an amputee using an ankle-foot prosthesis by simultaneously optimizing human movements and prosthesis actuation, minimizing a weighted sum of human metabolic and prosthesis costs. The resulting Pareto optimal solutions predict that increasing prosthesis energy cost, decreasing prosthesis mass, and allowing asymmetric gaits all decrease human metabolic rate for a given speed and alter human kinematics. The metabolic rates increase monotonically with speed. Remarkably, by performing an analogous optimization for a non-amputee human, we predict that an amputee walking with an appropriately optimized robotic prosthesis can have a lower metabolic cost - even lower than assuming that the non-amputee’s ankle torques are cost-free.

  17. Body image and prosthesis satisfaction in the lower limb amputee.

    OpenAIRE

    Murray, Craig; Fox, Jezz

    2002-01-01

    Purpose: This study examines the relationship between prosthesis satisfaction and body image in lower limb prosthesis users, and the gendered variations within these relationships. Method: A total of 44 valid responses were obtained to an Internet survey regarding prosthesis satisfaction, body image, and phantom pain. Spearman Rho correlations were calculated for these three domains. Results: Moderate to high negative correlations were observed between Body Image Disturbance and Prosthesis Sa...

  18. Implant-Retained Auricular Prosthesis: A Case Report

    OpenAIRE

    Ozturk, A. Nilgun; Usumez, Aslihan; Tosun, Zekeriya

    2010-01-01

    Extraoral implant retained prosthesis have been proven to be a predictable treatment option for maxillofacial rehabilitation. This case report describes the clinical and laboratory procedures for fabricating an auricular prosthesis. In this case report, an auricular prosthesis was fabricated for a patient who lost the left and right external ear in an electrical burn. Extraoral implants and bar-and-clip retention for the proper connection of the auricular prosthesis to implant were used. This...

  19. Periprosthetic fractures in the resurfaced hip--A case report and review of the literature.

    LENUS (Irish Health Repository)

    Brennan, Stephen A

    2013-02-01

    Traumatic periprosthetic fractures adjacent a hip resurfacing prosthesis are rare. When proximal fractures are encountered the obvious surgical solution is to revise to a large head stemmed femoral component. A previously well functioning implant may however be retained as various non-operative and operative treatment options exist. This paper reports the case history of a traumatic periprosthetic fracture successfully treated with cannulated screw fixation and reviews the current literature.

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

    Directory of Open Access Journals (Sweden)

    Logoluso Nicola

    2011-05-01

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