WorldWideScience

Sample records for artificial joint replacements

  1. [Short-term effectiveness of Swanson artificial joint replacement in treating posttraumatic metacarpophalangeal joint stiffness].

    Science.gov (United States)

    Lu, Hui; Shen, Xiangqian; Xu, Jihua; Huang, Xin; Ye, Po; Wu, Shoucheng

    2011-11-01

    To investigate the short-term effectiveness of Swanson artificial joint replacement in treating post-traumatic metacarpophalangeal joint stiffness. Between August 2007 and May 2010, 11 cases (13 fingers) of metacarpophalangeal joint stiffness with soft tissue defects underwent Swanson artificial joint replacement. There were 7 males (9 fingers) and 4 females (4 fingers), aged 43 to 65 years with an average of 49 years. The involved fingers included 4 thumbs, 4 index fingers, 3 middle fingers, and 2 ring fingers. The types of injury included open and crush injury in 8 fingers, fracture of the metacarpophalangeal joint in 3 fingers, metacarpophalangeal joint severing in 2 fingers. The time from joint stiffness to hospitalization was 12 to 48 weeks (mean, 24 weeks). The joint activity was (136.82 +/- 28.96) degrees. According to total active motion (TAM) assessment, included good in 1 finger, fair in 6 fingers, and poor in 6 fingers before operation. The activities of daily living were assessed by Sollerman score, which was 45.64 +/- 11.04. The X-ray films and CT scan showed traumatic arthritis of the metacarpophalangeal joint. The incision healed by first intention. All patients were followed up 12 to 34 months (mean, 24.1 months). At last follow-up, the joint activity was (194.64 +/- 28.86) degrees, showing significant difference when compared with preoperative value (t = 25.214, P = 0.000). According to TAM assessment, including excellent in 1 finger, good in 4 fingers, fair in 7 fingers, and poor in 1 finger. The Sollerman score was 67.45 +/- 8.20 postoperatively, showing significant difference when compared with the preoperative score (t = -10.470, P = 0.000). X-ray examination showed no prosthesis fracture, periprosthetic fracture, or joint dislocation occurred at last follow-up. Swanson artificial joint replacement can be applied to treat post-traumatic metacarpophalangeal joint stiffness, which can improve the joint activity and has satisfactory short

  2. Joint Replacement (Finger and Wrist Joints)

    Science.gov (United States)

    ... wrist joints can all be replaced (Figure 1). Artificial joints in the hand may help: Reduce joint pain Restore or maintain joint motion Improve the look and alignment of the joint(s) Improve overall hand function Causes In a normal joint, bones have a smooth surface made of a substance ...

  3. [Replacement of invert-type artificial total scapula and shoulder joint prosthesis for malignant tumor].

    Science.gov (United States)

    Yin, Qingwei; Jiang, Yi; Xiao, Lianping

    2007-03-01

    To estimate the clinical curative effect of replacement of invert-type artificial total scapula and shoulder joint prosthesis and reserving arm with rehabilitation of function in the treatment of.malignant tumor in shoulder. From February 2001 and November 2004, five youth patients with primary malignant shoulder tumors were treated operatively by resection of neoplasms thoroughly, replacement of invert-type artificial total shoulder blade and joint prosthesis, the functional reconstruction. Of them, there were 4 males and 1 female, aging from 19 to 26 years with an average of 23.6 years. Two cases were diagnosed as having osteosarcoma, one as having chondrosarcoma, and 2 as having Ewing sarcoma. After operation, the upper limbs was immobilized for 3 weeks. The rehabilitation training including passive exercise and initiative exercise. The average operative time was 425 min (380 to 530 min), and the blood loss ranged from 1250 ml to 1900 ml (1540 ml on average). The follow-up ranged from 7 to 52 months, with an average of 24.6 months. Postoperative complication included 1 case of pneumothorax, one case of shoulder incision skin part necrosis and 1 case of clavicle stump raising and pierce skin with shallow infection. No complication of postoperative incision deeply infection, nerve damage and prosthesis exposure or dislocation occurred. According to the scoring system of JOA (Japan orthopaedics association), the average score was 65 (60 to 72). The flexion and extension function of elbow joint recovered to normal. The replacement of invert-type artificial total scapula and shoulder joint prosthesis is an efficacious method for the treatment of malignant tumor in shoulder. There are advantages of numerous adaption, wide range of motion and good stability. It can not only reserve arm but also rehabilitate function.

  4. Artificial Disc Replacement

    Science.gov (United States)

    ... Spondylolisthesis BLOG FIND A SPECIALIST Treatments Artificial Disc Replacement (ADR) Patient Education Committee Jamie Baisden The disc ... Disc An artificial disc (also called a disc replacement, disc prosthesis or spine arthroplasty device) is a ...

  5. 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. ...

  6. 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 ...

  7. Knee joint replacement - slideshow

    Science.gov (United States)

    ... medlineplus.gov/ency/presentations/100088.htm Knee joint replacement - series—Normal anatomy To use the sharing features ... M. Editorial team. Related MedlinePlus Health Topics Knee Replacement A.D.A.M., Inc. is accredited by ...

  8. Joint replacement in Zambia

    African Journals Online (AJOL)

    MJZ

    Objective: This paper presents the short-term findings from a joint replacement register started at the Zambian-Italian Orthopaedic Hospital (ZIOH) in Lusaka and compares the variables entered in this register with those captured in the Malawian. National Joint Register for purposes of synchronizing these in the near future ...

  9. Anatomic variation of the deep venous system and its relationship with deep vein thrombosis found on the lower extremity venograms that were obtained after artificial joint replacements

    International Nuclear Information System (INIS)

    Lee, Min Sun; Lee, Jee Eun; Hwang, Ji Young; Shim, Sung Shine; Yoo, Jeong Hyun; Suh, Jeong Soo; Park, Jae Young

    2006-01-01

    We wanted to evaluate the anatomic variations, the number of valves and the presence of deep vein thrombosis (DVT) on the lower extremity venograms obtained after artificial joint replacements, and we also wanted to determine the correlation of the incidence of DVT with the above-mentioned factors and the operation sites. From January to June 2004, conventional ascending contrast venographies of the lower extremities were performed in 119 patients at 7-10 days after artificial joint replacement, and all the patients were asymptomatic. Total knee replacement was done for 152 cases and total hip replacement was done for 34 cases. On all the venographic images of 186 limbs, the anatomic variations were classified and the presence of DVT was evaluated; the number of valves in the superficial femoral vein (SFV) and calf veins was counted. The sites of DVT were classified as calf, thigh and pelvis. Statistically, chi square tests and Fischer's exact tests were performed to determine the correlation of the incidence of DVT with the anatomic variations, the numbers of valves and the operation sites. Theoretically, there are 9 types of anatomical variation in the deep vein system of the lower extremity that can be classified, but only 7 types were observed in this study. The most frequent type was the normal single SFV type and this was noted in 117 cases (63%), and the others were all variations (69 cases, 37%). There was a 22.2% incidence of DVT (69 cases) in the normal single SFV type and 26.4% (17 cases) in the other variations. No significant difference was noted in the incidences of DVT between the two groups. In addition, no significant statistical differences were noted for the incidences of DVT between the single or variant multiple veins in the SFV and the popliteal vein (PV) respectively, between the different groups with small or large numbers of valves in the thigh and calf, respectively, and also between the different operation sites of the hip or knee

  10. Anatomic variation of the deep venous system and its relationship with deep vein thrombosis found on the lower extremity venograms that were obtained after artificial joint replacements

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Min Sun; Lee, Jee Eun; Hwang, Ji Young; Shim, Sung Shine; Yoo, Jeong Hyun; Suh, Jeong Soo; Park, Jae Young [College of Medicine, Ewha Womans University, Seoul (Korea, Republic of)

    2006-11-15

    We wanted to evaluate the anatomic variations, the number of valves and the presence of deep vein thrombosis (DVT) on the lower extremity venograms obtained after artificial joint replacements, and we also wanted to determine the correlation of the incidence of DVT with the above-mentioned factors and the operation sites. From January to June 2004, conventional ascending contrast venographies of the lower extremities were performed in 119 patients at 7-10 days after artificial joint replacement, and all the patients were asymptomatic. Total knee replacement was done for 152 cases and total hip replacement was done for 34 cases. On all the venographic images of 186 limbs, the anatomic variations were classified and the presence of DVT was evaluated; the number of valves in the superficial femoral vein (SFV) and calf veins was counted. The sites of DVT were classified as calf, thigh and pelvis. Statistically, chi square tests and Fischer's exact tests were performed to determine the correlation of the incidence of DVT with the anatomic variations, the numbers of valves and the operation sites. Theoretically, there are 9 types of anatomical variation in the deep vein system of the lower extremity that can be classified, but only 7 types were observed in this study. The most frequent type was the normal single SFV type and this was noted in 117 cases (63%), and the others were all variations (69 cases, 37%). There was a 22.2% incidence of DVT (69 cases) in the normal single SFV type and 26.4% (17 cases) in the other variations. No significant difference was noted in the incidences of DVT between the two groups. In addition, no significant statistical differences were noted for the incidences of DVT between the single or variant multiple veins in the SFV and the popliteal vein (PV) respectively, between the different groups with small or large numbers of valves in the thigh and calf, respectively, and also between the different operation sites of the hip or knee

  11. Total ankle joint replacement.

    Science.gov (United States)

    2016-02-01

    Ankle arthritis results in a stiff and painful ankle and can be a major cause of disability. For people with end-stage ankle arthritis, arthrodesis (ankle fusion) is effective at reducing pain in the shorter term, but results in a fixed joint, and over time the loss of mobility places stress on other joints in the foot that may lead to arthritis, pain and dysfunction. Another option is to perform a total ankle joint replacement, with the aim of giving the patient a mobile and pain-free ankle. In this article we review the efficacy of this procedure, including how it compares to ankle arthrodesis, and consider the indications and complications. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  12. Knee joint replacement

    Science.gov (United States)

    Total knee replacement; Knee arthroplasty; Knee replacement - total; Tricompartmental knee replacement; Subvastus knee replacement; Knee replacement - minimally invasive; Knee arthroplasty - minimally ...

  13. Knee joint replacement - discharge

    Science.gov (United States)

    ... Knee replacement - total - discharge; Tricompartmental knee replacement - discharge; Osteoarthritis - knee replacement discharge ... such as downhill skiing or contact sports like football and soccer. But, you should be able to ...

  14. 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.

  15. Older Person's Guide to Joint Replacement

    Science.gov (United States)

    ... Related Documents PDF Older Person’s Guide to Joint Replacement Download Join our e-newsletter! Resources Older Person’s Guide to Joint Replacement Tools and Tips Printer-friendly PDF Click here ...

  16. Skilled nursing facilities after joint replacement

    Science.gov (United States)

    ... care providers in the weeks before your joint replacement. They can advise you about whether going directly ... of many people who have had a joint replacement? Can they tell you how many? A good ...

  17. Joint replacement in Zambia: A review of Hip & Knee Replacement ...

    African Journals Online (AJOL)

    Background: Incidence of major joint replacement surgery is on the rise in Africa but this trend has not been matched by proper audits in the form of National Joint Registries. Objective: This paper presents the short-term findings from a joint replacement register started at the Zambian-Italian Orthopaedic Hospital (ZIOH) in ...

  18. Synthetic Versus Tissue-Engineered Implants for Joint Replacement

    Directory of Open Access Journals (Sweden)

    Duncan E. T. Shepherd

    2007-01-01

    Full Text Available Human synovial joints are remarkable as they can last for a lifetime. However, they can be affected by disease that may lead to destruction of the joint surface. The most common treatment in the advanced stages of joint disease is artificial joint replacement, where the diseased synovial joint is replaced with an artificial implant made from synthetic materials, such as metals and polymers. A new technique for repairing diseased synovial joints is tissue engineering where cells are used to grow replacement tissue. This paper explores the relative merits of synthetic and tissue-engineered implants, using joint replacement as an example. Synthetic joint replacement is a well-established procedure with the advantages of early mobilisation, pain relief and high patient satisfaction. However, synthetic implants are not natural tissues; they can cause adverse reactions to the body and there could be a mismatch in mechanical properties compared to natural tissues. Tissue-engineered implants offer great potential and have major advantages over synthetic implants as they are natural tissue, which should ensure that they are totally biocompatible, have the correct mechanical properties and integrate well with the existing tissue. However, there are still many limitations to be addressed in tissue engineering such as scaling up for production, bioreactor design, appropriate regulation and the potential for disease to attack the new tissue-engineered implant.

  19. Total joint replacement preadmission programs.

    Science.gov (United States)

    Messer, B

    1998-01-01

    Patients begin to formulate their expectations of the postoperative hospitalization during the preadmission program. The challenge is to better understand the factors patients consider when formulating judgments about the quality of preadmission education. For example, it may be that perceptions of the preadmission program are influenced by what patients believe about their postoperative pain and functional abilities. Specific attention needs to be given both preoperatively and postoperatively to instructing patients on realistic expectations for recovery. One other method of measuring patient outcomes is with the Health Status Profile (SF-36) (Response Healthcare Information Management, 1995). The SF-36 approach emphasizes the outcome of medical care as the patient sees it, in addition to a clinical evaluation of successful health care. This form is currently initiated in the physician's office and returned for scanning at the preadmission class. The patient then completes another SF-36 at 6 months and every year thereafter to compare measurable outcomes. Patients intending to have elective total joint replacements experience anxiety and require much support and education. An effective preadmission program is a major investment in a patient's recovery, as well as a unique marketing tool to customers. Preadmission programs can be viewed as an opportunity to enhance customer satisfaction. Preadmission clinics are an excellent means for nurses to improve the quality of patient care through patient education. the overall goal of preadmission testing programs is to ensure patient preparedness while increasing quality health care and overall customer satisfaction. To enhance program effectiveness, health care providers must lead collaborative efforts to improve the efficiency of systems.

  20. Design of artificial human joints & organs

    CERN Document Server

    Pal, Subrata

    2013-01-01

    This book covers the design science and methodology of artificial joints and organs.  It presents the mechanical characterization of the hard and soft tissues as well as the viscoelastic properties of the tissue.

  1. Composite artificial semi-knee joint system.

    Science.gov (United States)

    Li, Z; Xu, S-F; Li, D-C; Sun, Z; Zhang, T; Lu, J-X; Wang, Z

    2014-01-01

    The purpose of the study was to investigate the clinical implantation protocol of custom-made artificial semi-knee joint based on computer-aided design so as to improve the limb salvage efficiency. The custom-made artificial semi-knee joint was designed and manufactured based on rapid prototyping technology. The repeated modifications were carried out in the design and manufacture of the semi-knee joint, together with the operation protocol. Clinical trial was conducted on 2 cases of osteosarcoma, one receiving allograft prosthesis composite transplantation, and the other receiving synthetic bone graft prosthesis composite transplantation. The clinical outcomes of the 2 patients were evaluated. The custom-made artificial semi-knee joint met the clinical customization needs. In clinical trial, 18-month follow-up demonstrated the satisfactory knee joint function recovery in near future. The custom-made artificial semi-knee joint based on computer-aided design can afford satisfactory knee joint function recovery following allograft bone transplantation.

  2. 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...

  3. Joint Replacement Surgery: What You Need to Know

    Science.gov (United States)

    ... What you Need to Know Follow us Joint Replacement Surgery: What you Need to Know Joint replacement surgery removes damaged or diseased parts of a ... Years of use Disease The goals of joint replacement surgery are to relieve pain, help the joint ...

  4. Perspectives on artificial joint design.

    Science.gov (United States)

    Frost, H M

    1992-01-01

    Due to poor interdisciplinary communication, many artifical joint designs fail to account for some features that normally allow bones to survive for life. In part, these features concern modeling drifts and remodeling basic multicellular units (BMUs), the microdamage thresholds of bone, its load-grain alignment and shear lock properties, load focusing and defocusing, mechanical usage/strain thresholds for controlling the biological mechanisms, and the regional acceleratory phenomenon. This article reviews briefly some major aspects of these features and suggests how implant design might account for them.

  5. Joint replacement surgery in homeless veterans

    Directory of Open Access Journals (Sweden)

    Chase G. Bennett, MD

    2017-12-01

    Full Text Available Total joint arthroplasty (TJA in a homeless patient is generally considered contraindicated. Here, we report our known medical and social (housing and employment results of homeless veterans who had TJA. Thirty-seven TJAs were performed on 33 homeless patients (31 men at our hospital between November 2000 and March 2014. This was 1.2% of all TJAs. Average age was 54 years. Average hospital stay was 4.1 days. There were no major inpatient complications. Thirty-four cases had at least 1-year follow-up in any clinic within the Veterans Affairs health care system. There were no known surgery-related reoperations or readmissions. At final follow-up, 24 patients had stable housing and 9 were employed. The extensive and coordinated medical and social services that were provided to veterans from the Department of Veterans Affairs contributed to our positive results. Keywords: Homeless, Veteran, Joint replacement, Total hip, Total knee, Employment

  6. Patellofemoral Joint Replacement and Nickel Allergy: An Unusual Presentation

    OpenAIRE

    Syed, Farhan; Jenner, Edward; Faisal, Mohammad

    2015-01-01

    Metal allergy is an unusual complication of joint replacement that may cause aseptic loosening and necessitate joint revision surgery. We present the case of nickel allergy causing aseptic loosening following patellofemoral joint replacement (PFJR) in a 54-year-old male. Joint revision surgery to a nickel-free total knee replacement was performed with good results. Our literature review shows that there is no evidence to guide the management of metal allergy in PFJR. The evidence from studies...

  7. On Patellofemoral joint replacement - Clinical, radiological, and numerical studies.

    NARCIS (Netherlands)

    Jonbergen, J.P.W. van

    2011-01-01

    Patellofemoral, osteoarthritis, joint replacement, arthroplasty, anterior knee pain Isolated patellofemoral joint osteoarthritis is a degenerative disorder of the knee estimated to occur in approximately 4% to 24% of patients with osteoarthritis of the knee. Mild isolated patellofemoral

  8. Principles of human joint replacement design and clinical application

    CERN Document Server

    Buechel, Frederick F

    2015-01-01

    This book is written for the users and designers of joint replacements. In its second extended edition it conveys to the reader the knowledge accumulated by the authors during their forty year effort on the development of replacement devices for the lower limb for the purpose of aiding the reader in their design and evaluation of joint replacement devices. The early chapters describe the engineering, scientific and medical principles needed for replacement joint evaluation. One must understand the nature and performance of the materials involved and their characteristics in vivo, i.e. the response of the body to implant materials. It is also essential to understand the response of the implants to applied loading and motion, particularly in the hostile physiological environment. A chapter describes the design methodology now required for joint replacement in the USA and EU countries. The remaining chapters provide a history of joint replacement, an evaluation of earlier and current devices and sample case hist...

  9. Anesthesia for joint replacement surgery: Issues with coexisting diseases

    Directory of Open Access Journals (Sweden)

    P N Kakar

    2011-01-01

    Full Text Available The first joint replacement surgery was performed in 1919. Since then, joint replacement surgery has undergone tremendous development in terms of surgical technique and anesthetic management. In this era of nuclear family and independent survival, physical mobility is of paramount importance. In recent years, with an increase in life expectancy, advances in geriatric medicine and better insurance coverage, the scenario of joint replacement surgery has changed significantly. Increasing number of young patients are undergoing joint replacement for pathologies like rheumatoid arthritis and ankylosing spondylitis. The diverse pathologies and wide range of patient population brings unique challenges for the anesthesiologist. This article deals with anesthetic issues in joint replacement surgery in patients with comorbidities.

  10. Principles of Human Joint Replacement Design and Clinical Application

    CERN Document Server

    Buechel, Frederick F

    2012-01-01

    Drs. Buechel, an orthopaedic surgeon, and Pappas, a professor of Mechanical Engineering, are the designers of several successful joint replacement systems. The most well-known of these is the pioneering LCS knee replacement. They have written this book for the users and designers of joint replacements. It is an attempt to convey to the reader the knowledge accumulated by the authors during their thirty five year effort on the development of replacement devices for the lower limb for the purpose of aiding the reader in their design and evaluation of joint replacement devices. The early chapters describe the engineering, scientific and medical principles needed for replacement joint evaluation. One must understand the nature and performance of the materials involved and their characteristics in vivo, i.e. the response of the body to implant materials. It is also essential to understand the response of the implants to applied loading and motion, particularly in the hostile physiological environment. A chapter de...

  11. Physical activity in the elderly who underwent joint replacement surgery in the course of rheumatic diseases

    Directory of Open Access Journals (Sweden)

    Agnieszka Prusinowska

    2016-07-01

    Full Text Available According to the forecasts of the Central Statistical Office of Poland, in 2030 people at the age of 65 and older will account for 23.8%, i.e. their number will amount to approx. 8.5 m people. Geriatric rheumatic patients more often decide to undergo surgical joint replacement. According to the National Health Fund, the number of joint replacement services provided in 2014 increased by 93%, as compared to 2005. Improving the physical performance of this constantly expanding group of patients requires taking into account many factors to raise their functional status, reduce the risk of falling, teach rules of proper functioning with an artificial joint and encourage unassisted physical activity. Restoring fitness and independence is a difficult but necessary task due to an increasing number of seniors with replaced joint.

  12. 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.

  13. an example of studies comparing artificial disc replacement with ...

    African Journals Online (AJOL)

    2015-07-22

    Jul 22, 2015 ... Cervical artificial disc replacement (C-ADR) is now an alternative to anterior cervical discectomy and fusion. (ACDF). Many studies have evaluated the efficacy of C-ADR compared with ACDF. This led to a series of systematic reviews and meta-analyses to evaluate the evidence of the superiority of one ...

  14. Comprehensive Care For Joint Replacement Model - Provider Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — Comprehensive Care for Joint Replacement Model - provider data. This data set includes provider data for two quality measures tracked during an episode of care:...

  15. Joint Replacement Surgery: Health Information Basics for You and Your Family

    Science.gov (United States)

    ... Initiative Breadcrumb Home Health Topics English Español Joint Replacement Surgery Basics In-Depth Download Download EPUB Download ... What is it? Points To Remember About Joint Replacement Surgery Joint replacement surgery removes damaged or diseased ...

  16. Full Scale 3D Preoperative Planning System of the Ankle Joint Replacement Surgery with Multimedia System

    Directory of Open Access Journals (Sweden)

    Shuh-Ping Sun

    2014-05-01

    Full Text Available This study is intended to develop a computer-aided pre-surgical planning and simulating system in a multimedia environment for ankle joint replacement surgery. This system uses full-scale 3D reverse engineering techniques in design and development of the pre-surgical planning modules for ankle joint replacement surgery. This planning system not only develops the real-scale 3D image of the artificial ankle joint but also provides a detailed interior measurement of the ankle joint from various cutting planes. In this study, we apply the multimedia user interface to integrate different software functions into a surgical planning system with integrated functions. The functions include 3D model image acquisition, cutting, horizontal shifting and rotation of related bones (tibia and talus of the ankle joint in the predetermined time. For related bones of the ankle joint, it can also be used to design artificial ankle joints for adults in Taiwan. Those planning procedures can be recorded in this system for further research and investigation. Furthermore, since this system is a multimedia user interface, surgeons can use this system to plan and find a better and more efficient surgical approach before surgery. A database is available for this system to update and expand, which can provide different users with clinical cases as per their experience and learning.

  17. Total hip replacement for Mseleni Joint Disease undertaken in a ...

    African Journals Online (AJOL)

    Total hip replacement for Mseleni Joint Disease undertaken in a rural hospital: five-year follow-up. Abstract. Objective: The objective of this project was to ascertain whether it is reasonable to perform specialist surgery for Mseleni Joint Disease (MJD) in a rural hospital by assessing the medium- term outcome of surgery for ...

  18. Sweet proteins – Potential replacement for artificial low calorie sweeteners

    Science.gov (United States)

    Kant, Ravi

    2005-01-01

    Exponential growth in the number of patients suffering from diseases caused by the consumption of sugar has become a threat to mankind's health. Artificial low calorie sweeteners available in the market may have severe side effects. It takes time to figure out the long term side effects and by the time these are established, they are replaced by a new low calorie sweetener. Saccharine has been used for centuries to sweeten foods and beverages without calories or carbohydrate. It was also used on a large scale during the sugar shortage of the two world wars but was abandoned as soon as it was linked with development of bladder cancer. Naturally occurring sweet and taste modifying proteins are being seen as potential replacements for the currently available artificial low calorie sweeteners. Interaction aspects of sweet proteins and the human sweet taste receptor are being investigated. PMID:15703077

  19. Sweet proteins – Potential replacement for artificial low calorie sweeteners

    Directory of Open Access Journals (Sweden)

    Kant Ravi

    2005-02-01

    Full Text Available Abstract Exponential growth in the number of patients suffering from diseases caused by the consumption of sugar has become a threat to mankind's health. Artificial low calorie sweeteners available in the market may have severe side effects. It takes time to figure out the long term side effects and by the time these are established, they are replaced by a new low calorie sweetener. Saccharine has been used for centuries to sweeten foods and beverages without calories or carbohydrate. It was also used on a large scale during the sugar shortage of the two world wars but was abandoned as soon as it was linked with development of bladder cancer. Naturally occurring sweet and taste modifying proteins are being seen as potential replacements for the currently available artificial low calorie sweeteners. Interaction aspects of sweet proteins and the human sweet taste receptor are being investigated.

  20. Lower limb joint replacement in rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Clement Nicholas D

    2012-06-01

    Full Text Available Abstract Introduction There is limited literature regarding the peri-operative and surgical management of patients with rheumatoid disease undergoing lower limb arthroplasty. This review article summarises factors involved in the peri-operative management of major lower limb arthroplasty surgery for patients with rheumatoid arthritis. Methods We performed a search of the medical literature, using the PubMed search engine (http://www.pubmed.gov. We used the following terms: ‘rheumatoid’ ‘replacement’ ‘arthroplasty’ and ‘outcome’. Findings The patient should be optimised pre-operatively using a multidisciplinary approach. The continued use of methotrexate does not increase infection risk, and aids recovery. Biologic agents should be stopped pre-operatively due the increased infection rate. Patients should be made aware of the increased risk of infection and periprosthetic fracture rates associated with their disease. The surgical sequence is commonly hip, knee and then ankle. Cemented total hip replacement (THR and total knee replacement (TKR have superior survival rates over uncemented components. The evidence is not clear regarding a cruciate sacrificing versus retaining in TKR, but a cruciate sacrificing component limits the risk early instability and potential revision. Patella resurfacing as part of a TKR is associated with improved outcomes. The results of total ankle replacement remain inferior to THR and TKR. RA patients achieve equivalent pain relief, but their rehabilitation is slower and their functional outcome is not as good. However, the key to managing these complicated patients is to work as part of a multidisciplinary team to optimise their outcome.

  1. Joint replacement surgery and the innate immune system.

    Science.gov (United States)

    Goodman, Stuart B; Konttinen, Yrjo T; Takagi, Michiaki

    2014-01-01

    Total joint replacement is a highly successful, cost-effective surgical procedure that relieves pain and improves function for patients with end-stage arthritis. The most commonly used materials for modern joint replacements include metal alloys such as cobalt chrome and titanium alloys, polymers including polymethylmethacrylate and polyethylene, and ceramics. Implantation of a joint prosthesis incites an acute inflammatory reaction that is regulated by the innate immune system, a preprogrammed non-antigen specific biological response composed of cells, proteins, and other factors. This "frontline" immune mechanism was originally designed to combat invading microorganisms, but now responds to both pathogen-associated molecular patterns or PAMPS (by-products from microorganisms), and damage associated molecular patterns or DAMPS (molecular by-products from cells), via pattern recognition receptors (PRRs). In this way, potentially injurious stimuli that might disrupt the normal homeostatic regulatory mechanisms of the organism are efficiently dealt with, ensuring the survival of the host. Initial surgical implantation of the joint replacement, as well as ongoing generation of wear debris and byproducts during usage of the joint, activates the innate immune system. Understanding and potentially modulating these events may lead to improved function and increased longevity of joint replacements in the future.

  2. Risk factors for renal dysfunction after total hip joint replacement

    DEFF Research Database (Denmark)

    Hassan, Basim Kamil; Sahlström, Arne; Dessau, Ram Benny Christian

    2015-01-01

    BACKGROUND AND PURPOSE OF THE STUDY: Renal injury and dysfunction are serious complications after major surgery, which may lead to increased morbidity and mortality. The objective of our study was to identify the possible risk factors for renal dysfunction after total hip joint replacement surgery....... METHODS: A retrospective study was conducted among 599 consecutive primary hip joint replacements performed between January 2011 and December 2013. According to the RIFLE criteria, increased postoperative serum creatinine was considered indicative of postoperative renal injury. The Welch two-sample test...

  3. Medium term results of Avon patellofemoral joint replacement

    Directory of Open Access Journals (Sweden)

    Praveen K Sarda

    2011-01-01

    Conclusion: The Avon patellofemoral joint replacement provides predictably good results and excellent survivorship in the medium term, for isolated patellofemoral arthritis. However, progression of tibiofemoral arthritis remains unpredictable and therefore patient selection is crucial to ensure success. Clicking remains a potential problem and can compromise the postoperative results in upto 15% of the cases.

  4. A review of national shoulder and elbow joint replacement registries

    DEFF Research Database (Denmark)

    Rasmussen, Jeppe V; Olsen, Bo S; Fevang, Bjørg-Tilde S

    2012-01-01

    The aim was to review the funding, organization, data handling, outcome measurements, and findings from existing national shoulder and elbow joint replacement registries; to consider the possibility of pooling data between registries; and to consider wether a pan european registry might be feasible....

  5. Who should have knee joint replacement surgery for osteoarthritis?

    DEFF Research Database (Denmark)

    Dieppe, Paul; Lim, Keith; Lohmander, Stefan

    2011-01-01

    -20% of people who have this surgery are unhappy with the outcome, and have persistent pain. In this article we briefly discuss the variations in utilization of knee joint replacement, and then outline four different approaches to the selection and prioritisation of patients for this procedure. Consensus...

  6. Patellofemoral Joint Replacement and Nickel Allergy: An Unusual Presentation.

    Science.gov (United States)

    Syed, Farhan; Jenner, Edward; Faisal, Mohammad

    2015-01-01

    Metal allergy is an unusual complication of joint replacement that may cause aseptic loosening and necessitate joint revision surgery. We present the case of nickel allergy causing aseptic loosening following patellofemoral joint replacement (PFJR) in a 54-year-old male. Joint revision surgery to a nickel-free total knee replacement was performed with good results. Our literature review shows that there is no evidence to guide the management of metal allergy in PFJR. The evidence from studies of total knee replacement is limited to retrospective case series and case reports and gives contradictory recommendations. The optimal management strategy for metal allergy in PFJR is not clear. We recommend allergy testing in patients with history of metal allergy and use of an allergen-free implant in those with positive tests. As there is no gold standard test to establish metal allergy, the choice of test should be guided by availability and recommendation from the local unit of dermatology and allergy testing. We recommend investigation for metal allergy in patients with implant loosening where other causes have been excluded.

  7. Patellofemoral Joint Replacement and Nickel Allergy: An Unusual Presentation

    Directory of Open Access Journals (Sweden)

    Farhan Syed

    2015-01-01

    Full Text Available Metal allergy is an unusual complication of joint replacement that may cause aseptic loosening and necessitate joint revision surgery. We present the case of nickel allergy causing aseptic loosening following patellofemoral joint replacement (PFJR in a 54-year-old male. Joint revision surgery to a nickel-free total knee replacement was performed with good results. Our literature review shows that there is no evidence to guide the management of metal allergy in PFJR. The evidence from studies of total knee replacement is limited to retrospective case series and case reports and gives contradictory recommendations. The optimal management strategy for metal allergy in PFJR is not clear. We recommend allergy testing in patients with history of metal allergy and use of an allergen-free implant in those with positive tests. As there is no gold standard test to establish metal allergy, the choice of test should be guided by availability and recommendation from the local unit of dermatology and allergy testing. We recommend investigation for metal allergy in patients with implant loosening where other causes have been excluded.

  8. Rehabilitation after total joint replacement: a scoping study.

    Science.gov (United States)

    L Snell, Deborah; Hipango, Julia; Sinnott, K Anne; Dunn, Jennifer A; Rothwell, Alastair; Hsieh, C Jean; DeJong, Gerben; Hooper, Gary

    2018-07-01

    The evidence supporting rehabilitation after joint replacement, while vast, is of variable quality making it difficult for clinicians to apply the best evidence to their practice. We aimed to map key issues for rehabilitation following joint replacement, highlighting potential avenues for new research. We conducted a scoping study including research published between January 2013 and December 2016, evaluating effectiveness of rehabilitation following hip and knee total joint replacement. We reviewed this work in the context of outcomes described from previously published research. Thirty individual studies and seven systematic reviews were included, with most research examining the effectiveness of physiotherapy-based exercise rehabilitation after total knee replacement using randomized control trial methods. Rehabilitation after hip and knee replacement whether carried out at the clinic or monitored at home, appears beneficial but type, intensity and duration of interventions were not consistently associated with outcomes. The burden of comorbidities rather than specific rehabilitation approach may better predict rehabilitation outcome. Monitoring of recovery and therapeutic attention appear important but little is known about optimal levels and methods required to maximize outcomes. More work exploring the role of comorbidities and key components of therapeutic attention and the therapy relationship, using a wider range of study methods may help to advance the field. Implications for Rehabilitation Physiotherapy-based exercise rehabilitation after total hip replacement and total knee replacement, whether carried out at the clinic or monitored at home, appears beneficial. Type, intensity, and duration of interventions do not appear consistently associated with outcomes. Monitoring a patient's recovery appears to be an important component. The available research provides limited guidance regarding optimal levels of monitoring needed to achieve gains following hip

  9. [Progress on classification and application of artificial hip joint materials].

    Science.gov (United States)

    Wu, Xiao; He, Ben-xiang; Tan, Ya-jun

    2016-03-01

    The selection of the prosthetic material determine the success or failure of hip arthroplasty. Currently, the metals, ceramics, polymer composites and carbon materials are the main prosthetic materials of artificial hip joint. They have some progresses in biocompatibility, elastic modulus,mechanical properties, useful life, but they still can't reach the ideal standard of design. In this essay, we mainly review the characteristics and applications of the current artificial hip joint materials through its classification in order to provide a reference for choosing appropriate hip joint materials in clinic and increasing characteristic of materials. We consider the polymer composites has more advantages such as biocompatibility, mechanical properties, corrosion resistance and price, even if it has shortages in abrasion resistance. As the researches of polymer composites are main focus on abrasion resistance, articular surface and strength,and its performances are increased fast, it has a wide prospect in future.

  10. DETERMINING JOINT ANGLES OF ROBOT ARM BY ARTIFICIAL NEURAL NETWORK

    OpenAIRE

    ARSERİM, Muhammet Ali; DEMİR, Yakup

    2016-01-01

    Aim of this study is to solve inverse kinematic problem of a five axis articulated robot arm by using artificial neural network. Through this aim five axes articulated SCORBOT-ER VPlus robot arm is used. Experimental coordinate data for this robot arm is collected form a table, on which this robot arm is fixed and artificial neural network simulation, is implemented on MATLAB R2008A software for determining base, shoulder, and elbow joint angles. As a result it is seen that outputs of the ANN...

  11. 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.

  12. The Use of Titanium in the Friction of Artificial Joints

    Directory of Open Access Journals (Sweden)

    Sheykin, S.Ye.

    2015-05-01

    Full Text Available The possibility of using titanium in the friction of artificial joints is studying. Tribological characteristics of the friction pair titanium-hirulen is researching. The technology of diamond-abrasive machining, polishing and gas thermal nitridation spherical heads of pure titanium implants for hip person are developed. It is proved the increases of titanium head hardness achieved by pre-grinding the surface layer structure after cold plastic deformation.

  13. Outcomes of a Joint Replacement Surgical Home Model Clinical Pathway

    Directory of Open Access Journals (Sweden)

    Avinash Chaurasia

    2014-01-01

    Full Text Available Optimizing perioperative care to provide maximum benefit at minimum cost may be best achieved using a perioperative clinical pathway (PCP. Using our joint replacement surgical home (JSH model PCP, we examined length of stay (LOS following total joint arthroplasty (TJA to evaluate patient care optimization. We reviewed a spectrum of clinical measurements in 190 consecutive patients who underwent TJA. Patients who had surgery earlier in the week and who were earlier cases of the day had a significantly lower LOS than patients whose cases started both later in the week and later in the day. Patients discharged home had significantly lower LOS than those discharged to a secondary care facility. Patients who received regional versus general anesthesia had a significantly lower LOS. Scheduling patients discharged to home and who will likely receive regional anesthesia for the earliest morning slot and earlier in the week may help decrease overall LOS.

  14. Ankle replacement - discharge

    Science.gov (United States)

    ... total - discharge; Total ankle arthroplasty - discharge; Endoprosthetic ankle replacement - discharge; Osteoarthritis - ankle ... You had an ankle replacement. Your surgeon removed and reshaped ... an artificial ankle joint. You received pain medicine and were ...

  15. [Fractures of the acetabulum: complications and joint replacement].

    Science.gov (United States)

    Herath, S C; Holstein, J H; Pizanis, A; Pohlemann, T

    2014-08-01

    Acetabular fractures assume a special role amongst the fractures of the pelvis, because they involve a major weight-bearing joint. As those fractures mostly result from exposure to great force, and because of their location in an anatomically complex region, a high rate of complications has to be anticipated. Besides general and perioperative complications long-term consequences, especially post-traumatic arthrosis, are relevant problems when it comes to treating fractures of the acetabulum. The primary reconstruction of the acetabulum, as well as a possibly necessary prosthetic replacement of the hip joint, makes high demands on the diagnostic and operative capabilities of the attending physician. Exact knowledge of the specific risks and pitfalls for each type of fracture and for the specific surgical techniques is crucial for a successful treatment. Due to the much worse long-term outcome when compared to primary total hip replacement in patients with osteoarthritis, acetabular fractures should, regardless of the patient's age, whenever possible be treated by operative reconstruction. Georg Thieme Verlag KG Stuttgart · New York.

  16. [Early effectiveness of discover cervical artificial disc replacement in treatment of cervical spondylosis].

    Science.gov (United States)

    Qian, Yufeng; Xue, Feng; Sheng, Xiaowen; Lu, Jianmin; Chen, Bingqian

    2012-03-01

    To investigate the early effectiveness of the Discover cervical artificial disc replacement in treating cervical spondylosis. Qualified for the selective standard, 24 patients with cervical spondylosis were treated between March 2010 and March 2011. Of 24 patients, 13 patients underwent anterior cervical decompression and fusion (ACDF) (ACDF group, between March 2010 and September 2010) and 11 patients underwent Discover cervical artificial disc replacement (CADR group, between September 2010 and March 2011). There was no significant difference in gender, age, disease duration, lesions typing, and affected segments between 2 groups (P > 0.05). The operative time, blood loss, and complications were recorded. Japanese Orthopaedic Association (JOA) scores, Neck Disability Index (NDI) scores, and Odom's scores were used to evaluate the postoperative effectiveness. In CADR group, the cervical range of motion (ROM) in all directions, and prosthesis eccentricity were measured before and after operation. Symptoms disappeared and no complication occurred after operation in the patients of 2 groups. The patients were followed up 12 to 18 months (mean, 15.3 months) in ACDF group and 6 to 12 months (mean, 9.6 months) in CADR group. The NDI scores in CADR group were significantly higher than those in ACDF group at 1, 3, and 6 months (P 0.05). According to Odom's score at last follow-up, the results were excellent in 6 cases, good in 4 cases, and fair in 3 cases with an excellent and good rate of 76.92% in ACDF group, and were excellent in 9 cases, good in 1 case, and poor in 1 case with an excellent and good rate of 90.91% in CADR group, showing no significant difference (chi2 = 3.000, P = 0.223). The patients in CADR group had significant limit of cervical joint ROM in flexion and extension and right bending at 1 month (P value (P < 0.05). Meanwhile, ROM in left bending were bigger than that in right bending in replaced segment and upper segment (P < 0.05), and the ROM

  17. Application of digital templates to guide total alloplastic joint replacement surgery with biomet standard replacement system.

    Science.gov (United States)

    Bai, Guo; He, Dongmei; Yang, Chi; Chen, Minjie; Yuan, Jianbing; Wilson, Julian J

    2014-12-01

    To design and manufacture digital templates to guide Biomet total alloplastic joint replacement surgery (Biomet, Warsaw, IN) and evaluate the clinical efficacy. Six patients who underwent total alloplastic joint replacement surgery from November 2013 to March 2014 were included in this study. Before surgery, the Biomet standard prostheses were scanned and imported into the ProPlan CMF 1.4 software (Materialise NV, Leuven, Belgium) for virtual positioning and osteotomy planning. Digital templates were then designed to guide intraoperative bone trimming and prosthesis placement. A postoperative computed tomography scan was taken and used to measure how well the postsurgical images corresponded to the images generated in the preoperative plan. The digital templates were smoothly positioned and easily adapted, and they accurately guided bone trimming and prosthesis implantation. In addition, vital anatomic structures such as the skull base and inferior alveolar neurovascular bundle were not injured during the procedures. The result of the merged postoperative and preoperative computed tomography scans showed that the position of the prostheses corresponded quite accurately to the preoperative design, with an error of 1.139±0.183 mm. Digital templates can accurately guide the bone trimming required for placement of Biomet total alloplastic joints. Likewise, these templates help place the prostheses in the desired locations, enhance stability, and avoid damage to the skull base and inferior alveolar neurovascular bundle. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  18. Elbow kinematics : Studies of the elbow joint under normal conditions and after joint replacement

    OpenAIRE

    Ericson, Anne

    2010-01-01

    Background: Total elbow arthroplasty (TEA) is used for treatment of patients with severe pain and disability due to reumatoid arthritis. Long term results are not as good as for hip and knee replacements. Further development of the implant designs and surgical technique based on proper knowledge of the in vivo biomechanical joint properties are required to improve results. Aim: To analyse the variation and the position of the instantaneous flexion axes in vivo in the nor...

  19. Reconstruction of chronic acromioclavicular joint disruption with artificial ligament prosthesis

    Directory of Open Access Journals (Sweden)

    Chouhan Devendra Kumar

    2013-08-01

    Full Text Available 【Abstract】Objective: Management of Rockwood type 3 acromioclavicular disruptions is a matter of debate. Should we adopt conservative or operative measures at first presentation? It is not clear but most of the evidences are in favour of conservative management. We present our expe-rience in managing these patients surgically. Methods: We present a prospective series of eight cases of chronic Rockwood type 3 acromioclavicular joint disruptions treated surgically. Anatomical reconstruction of the coracoclavicular ligament was done by artificial braided polyester ligament prosthesis. Results: All the patients were able to perform daily activities from an average of the 14th postoperative day. All patients felt an improvement in pain, with decrease in ave-rage visual analogue scale from preoperative 6.5 points (range 3-9 points to 2.0 points (range 0-5 points, Constant score from 59% to 91% and American Shoulder and Elbow Surgeons shoulder score from 65 to 93 points postoperatively. These results improved or at least remained stationary on midterm follow-up, and no deterioration was recorded at an average follow-up of 46 months. Conclusion: This midterm outcome analysis of the artificial ligament prosthesis is the first such follow-up study with prosthesis. Our results are encouraging and justify the further use and evaluation of this relatively new and easily reproducible technique. Key words: Acromioclavicular joint; Prostheses and implants; Reconstructive surgical procedures; Ligaments

  20. Returning to sports after total joint replacements and tibial osteotomies: is it possible?

    Science.gov (United States)

    Lahav, Amit

    2012-09-01

    Total joint replacement and tibial osteotomies have been used for decades to return the individual to activities and relieve pain. According to the American Academy of Orthopaedic Surgeons, joint replacement is considered one of the most successful medical innovations of the 20th century. Hip and knee-replacement operations are increasing in frequency and are continuing to achieve pain relief and improve function for patients with arthritic joints. Demand for knee replacement is expected to double over the next five to 10 years and for hip replacement, it is expected to double over the next 10 to 15 years. The trend for joint replacement has begun to include the younger as well as the older still active individual. Younger patients are considering joint-replacement surgery earlier in life due to advances in surgery and devices. Since children begin sports at a fairly early age, once they reach young adulthood, their joints have sustained recurrent internal impact for many years leading to degeneration earlier in life. These younger patients are expecting and choosing to participate in sports even after surgery. They want to be able to coach and play sports with their children without pain. While pain relief has historically been the main reason people have joint replacement surgery--the need to improve joint-function has also become motivating for patients--especially those involved in athletic activities. Patients and orthopedic surgeons do not necessarily worry about the same things after joint-replacement surgery.

  1. [Antibiotic treatment for prevention of infectious complications in joint replacement].

    Science.gov (United States)

    Jahoda, D; Nyc, O; Pokorný, D; Landor, I; Sosna, A

    2006-04-01

    Prophylactic antibiotic treatment is mandatory in every operation involving an orthopedic implant. Carefully selected and correctly administered antibiotics can provide effective protection of the implant from bacterial colonization. The prevention of deep wound infection in joint replacement includes several procedures and measures which constitute three basic groups: 1) Promotion of patient's ability to resist infection (careful pre-operative preparation, elimination of potential infectious loci, good nutritional status, etc). 2) Optimal conditions for the operative wound (surgical technique, prophylactic antibiotics). 3) Reduction of the number of bacteria brought in the wound (control measures, super-sterile operating theatres). Clear rules for the system of prophylactic antibiotic treatment should be adopted. A program in which responsibility for antibiotic administration was shifted from the nursing staff to the anesthesiologist in the operating theatre showed improved outcomes and reduced costs. Poor timing of prophylactic antibiotic administration is one of the basic mistakes. If the wound happened to be contaminated during surgery, the first three post-operative hours would be most decisive for the development of infection. An effective bactericidal concentration of antibiotic should be present in tissues and serum immediately after surgery has begun. Therefore the appropriate time for antibiotic application is before a skin incision is made, and not after the operation has started; the highest serum and bone tissue levels appear 20 to 30 min. after intravenous antibiotic injection. To allow antibiotics to reach target tissues, they should be introduced at least 10 min. before tourniquet application. For long surgical procedures or when blood loss is high, an additional dose of antibiotics is recommended during the operation. If a sample for bacterial cultivation is required, antibiotic administration is postponed until during surgery. However, this is

  2. Choice of a Perioperative Analgesia Mode during Hip Joint Replacement

    Directory of Open Access Journals (Sweden)

    D. B. Borisov

    2010-01-01

    Full Text Available Objective: to evaluate the efficiency and safety of various perioperative analgesia modes during total hip joint replacement (THR. Subjects and methods. A randomized controlled trial enrolled 90 patients who were divided into 3 groups according to the choice of a perioperative analgesia mode on day 1: general sevofluorane anesthesia, by switching to intravenous patient-controlled analgesia with fentanyl (PCA, GA group, a combination of general and spinal bupiva-caine anesthesia, by switching to PCA with fentanyl (SA group, a combination of general and epidural ropivacaine anesthesia with continuous postoperative epidural ropivacaine infusion (EA group. All the patients received non-opi-oid analgesics after surgery. Results. Prolonged epidural block ensures better postoperative analgesia at rest and during mobilization and a less need for opioids than other analgesia modes (p<0.05. With neuroaxial block, the preoperative need for sympatomimetics is much higher than that in the GA group (p<0.05. There is also a trend toward a higher incidence of cardiac arrhythmias and postoperative nausea and vomiting in the SA and EA groups. There are no differences in the frequency of hemotransfusion and postoperative complications and the length of hospital stay. Conclusion. Prolonged epidural block provides excellent perioperative analgesia during THR, but the risk-benefit ratio needs to be carefully assessed when an analgesia mode is chosen.

  3. Patient factors in referral choice for total joint replacement surgery.

    Science.gov (United States)

    Conner-Spady, Barbara L; Marshall, Deborah A; Bohm, Eric; Dunbar, Michael J; Loucks, Lynda; Hennigar, Allan W; Frank, Cy; Noseworthy, Tom W

    2014-04-01

    Although the option of next available surgeon can be found on surgeon referral forms for total joint replacement surgery, its selection varies across surgical practices. Objectives are to assess the determinants of (a) a patient's request for a particular surgeon; and (b) the actual referral to a specific versus the next available surgeon. Questionnaires were mailed to 306 consecutive patients referred to orthopedic surgeons. We assessed quality of life (Oxford Hip and Knee scores, Short Form-12, EuroQol 5D, Pain Visual Analogue Scale), referral experience, and the importance of surgeon choice, surgeon reputation, and wait time. We used logistic regression to build models for the 2 objectives. We obtained 176 respondents (response rate, 58%), 60% female, 65% knee patients, mean age of 65 years, with no significant differences between responders versus nonresponders. Forty-three percent requested a particular surgeon. Seventy-one percent were referred to a specific surgeon. Patients who rated surgeon choice as very/extremely important [adjusted odds ratio (OR), 6.54; 95% confidence interval (CI), 2.57-16.64] and with household incomes of $90,000+ versus <$30,000 (OR, 5.74; 95% CI, 1.56-21.03) were more likely to request a particular surgeon. Hip patients (OR, 3.03; 95% CI, 1.18-7.78), better Physical Component Summary-12 (OR, 1.29; 95% CI, 1.02-1.63), and patients who rated surgeon choice as very/extremely important (OR, 3.88; 95% CI, 1.56-9.70) were more likely to be referred to a specific surgeon. Most patients want some choice in the referral decision. Providing sufficient information is important, so that patients are aware of their choices and can make an informed choice. Some patients prefer a particular surgeon despite longer wait times.

  4. Joint recovery programme versus usual care - An economic evaluation of a clinical pathway for joint replacement surgery

    NARCIS (Netherlands)

    Brunenberg, DE; van Steyn, MJ; Sluimer, JC; Bekebrede, LL; Bulstra, SK; Joore, MA

    2005-01-01

    Objective: The objective of the present study was to determine the incremental cost-effectiveness of a clinical pathway for patients undergoing joint replacement, the Joint Recovery Programme (JRP), as compared with usual care. The existing care process was revised to contain costs and shorten

  5. Optimal timing of joint replacement using mathematical programming and stochastic programming models.

    Science.gov (United States)

    Keren, Baruch; Pliskin, Joseph S

    2011-12-01

    The optimal timing for performing radical medical procedures as joint (e.g., hip) replacement must be seriously considered. In this paper we show that under deterministic assumptions the optimal timing for joint replacement is a solution of a mathematical programming problem, and under stochastic assumptions the optimal timing can be formulated as a stochastic programming problem. We formulate deterministic and stochastic models that can serve as decision support tools. The results show that the benefit from joint replacement surgery is heavily dependent on timing. Moreover, for a special case where the patient's remaining life is normally distributed along with a normally distributed survival of the new joint, the expected benefit function from surgery is completely solved. This enables practitioners to draw the expected benefit graph, to find the optimal timing, to evaluate the benefit for each patient, to set priorities among patients and to decide if joint replacement should be performed and when.

  6. Dissolution behaviour of silicon nitride coatings for joint replacements

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Maria [Materials in Medicine Group, Div. of Applied Materials Science, Dept. of Engineering Sciences, Uppsala University, Uppsala (Sweden); Bryant, Michael [Institute of Functional Surfaces (iFS), School of Mechanical Engineering, University of Leeds, Leeds (United Kingdom); Schmidt, Susann [Thin Film Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping (Sweden); Engqvist, Håkan [Materials in Medicine Group, Div. of Applied Materials Science, Dept. of Engineering Sciences, Uppsala University, Uppsala (Sweden); Hall, Richard M. [Institute of Medical and Biological Engineering (iMBE), School of Mechanical Engineering, University of Leeds, Leeds (United Kingdom); Neville, Anne [Institute of Functional Surfaces (iFS), School of Mechanical Engineering, University of Leeds, Leeds (United Kingdom); Persson, Cecilia, E-mail: cecilia.persson@angstrom.uu.se [Materials in Medicine Group, Div. of Applied Materials Science, Dept. of Engineering Sciences, Uppsala University, Uppsala (Sweden)

    2016-05-01

    In this study, the dissolution rate of SiN{sub x} coatings was investigated as a function of coating composition, in comparison to a cobalt chromium molybdenum alloy (CoCrMo) reference. SiN{sub x} coatings with N/Si ratios of 0.3, 0.8 and 1.1 were investigated. Electrochemical measurements were complemented with solution (inductively coupled plasma techniques) and surface analysis (vertical scanning interferometry and x-ray photoelectron spectroscopy). The dissolution rate of the SiN{sub x} coatings was evaluated to 0.2–1.4 nm/day, with a trend of lower dissolution rate with higher N/Si atomic ratio in the coating. The dissolution rates of the coatings were similar to or lower than that of CoCrMo (0.7–1.2 nm/day). The highest nitrogen containing coating showed mainly Si–N bonds in the bulk as well as at the surface and in the dissolution area. The lower nitrogen containing coatings showed Si–N and/or Si–Si bonds in the bulk and an increased formation of Si–O bonds at the surface as well as in the dissolution area. The SiN{sub x} coatings reduced the metal ion release from the substrate. The possibility to tune the dissolution rate and the ability to prevent release of metal ions encourage further studies on SiN{sub x} coatings for joint replacements. - Graphical abstract: Dissolution rates of SiN{sub 0.3}, SiN{sub 0.8}, and SiN{sub 1.1} coatings on CoCrMo compared to uncoated CoCrMo. Dissolution rates were obtained from i) electrochemical measurements of I{sub corr}, ii) the step height between covered and solution-exposed surfaces, measured using VSI, and iii) the ion concentration in the solution, measured with ICP. - Highlights: • The dissolution of SiN{sub x} coatings was investigated in comparison to (bulk) CoCrMo. • The coatings gave a lower or similar dissolution rate to CoCrMo, of 0.2–1.2 nm/day. • An increased nitrogen content in the coatings gave lower dissolution rates. • SiN{sub x} coatings on CoCrMo reduced the metal ion release

  7. Rapid replacement of bridge deck expansion joints study - phase I.

    Science.gov (United States)

    2014-12-01

    Bridge deck expansion joints are used to allow for movement of the bridge deck due to thermal expansion, dynamics loading, and : other factors. More recently, expansion joints have also been utilized to prevent the passage of winter de-icing chemical...

  8. Biomechanics of the natural, arthritic, and replaced human ankle joint

    Science.gov (United States)

    2014-01-01

    The human ankle joint complex plays a fundamental role in gait and other activities of daily living. At the same time, it is a very complicated anatomical system but the large literature of experimental and modelling studies has not fully described the coupled joint motion, position and orientation of the joint axis of rotation, stress and strain in the ligaments and their role in guiding and stabilizing joint motion, conformity and congruence of the articular surfaces, patterns of contact at the articular surfaces, patterns of rolling and sliding at the joint surfaces, and muscle lever arm lengths. The present review article addresses these issues as described in the literature, reporting the most recent relevant findings. PMID:24499639

  9. Rapid replacement of bridge deck expansion joints study - phase I : [tech transfer summary].

    Science.gov (United States)

    2014-12-01

    This initial research phase focused on documenting the current : means and methods of bridge expansion joint deterioration, : maintenance, and replacement and on identifying improvements : through all of the input gathered.

  10. Christiansen's artificial hip joints--what went wrong?

    Science.gov (United States)

    Sudmann, Einar; Ramstad, Knut Rasmus; Engesæter, Lars Birger

    2013-12-10

    Modern arthroplasty is undoubtedly the greatest contribution that orthopaedic surgery has ever made to medical science. The honour for the good results achieved with total hip replacement surgery goes chiefly to the Briton John Charnley (1911-1982). However, the Norwegian Tor Aas Christiansen (1917-1981) has also earned a place in this history. He wanted to improve the operative treatment of dislocated, medial fractures of the femoral neck, and in the 1960s he constructed a hemiprosthesis. Later, he also made a total prosthesis for the hip joint. Over time, the prostheses proved to be less than successful. Nevertheless, approximately 6,500 Christiansen prostheses were fitted in Norway before a prospective Charnley vs. Christiansen study at the Coastal Hospital in Hagavik finally put an end to his prostheses in 1983. Indirectly, the study led to the establishment of a national register of hip prostheses, now the National Arthroplasty Register, at Haukeland University Hospital. Based on our personal cooperation with Christiansen, as well as original drawings and correspondence from the Polaris factory in Sandnes, we will tell the story of Christiansen's hemi- and total prostheses. These are a key element in the history of hip arthroplasty in Norway.

  11. Development of artificial articular cartilage

    Indian Academy of Sciences (India)

    (UHMWPE) has been choice of orthopaedic bearing material in total joint replacement surgery since 1962, but wear of UHMWPE remains major problem facing the long term success and survival of the artificial joint. One of the main reasons of failure of the artificial joint fixation into the host bone is cellular reaction against ...

  12. pH and metal concentration of synovial fluid of osteoarthritic joints and joints with metal replacements.

    Science.gov (United States)

    Milošev, Ingrid; Levašič, Vesna; Vidmar, Janja; Kovač, Simon; Trebše, Rihard

    2017-11-01

    Due to degradation and metal dissolution during articulation of metal joint replacements the chemical periprosthetic environment may change. The aim was to establish whether metal replacements cause the local changes in pH and elevated metal concentrations. pH was measured on samples from 167 patients: native hip and knee osteoarthritic joints, joints with hip and knee replacements revised for aseptic or septic reasons. pH of synovial fluid and periprosthetic tissue was measured perioperatively using a microelectrode and pH indicator papers for removed metal components. Metal concentrations were measured in 21 samples using inductively coupled plasma mass spectrometry. The mean pH value of synovial fluid at native osteoarthritic joints (n = 101) was 7.78 ± 0.38. The mean pH value of synovial fluid at revision aseptic operation (n = 58) was 7.60 ± 0.31, with statistically significant difference (p = 0.002) compared to native osteoarthritic joints. The mean pH value of synovial fluid at revision septic operation (n = 8) was 7.55 ± 0.25, with statistically significant difference (p = 0.038) compared to native osteoarthritic joints. Measurements in tissue and at stems were not reliable. In the majority of samples taken at revision increased levels of cobalt and chromium were measured. A small but statistically significant difference was observed in the pH of synovial fluid between natural joints with degenerative diseases and joints treated with metal replacements. Based on the increased metal levels we expected the value of pH to be lower, but the influence of metal ions is counteracted by the buffering capacity of human body. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2507-2515, 2017. © 2016 Wiley Periodicals, Inc.

  13. Use of an Artificial Ligament Decreases Hip Dislocation and Improves Limb Function After Total Femoral Prosthetic Replacement Following Femoral Tumor Resection.

    Science.gov (United States)

    Du, Zhiye; Tang, Shun; Yang, Rongli; Tang, Xiaodong; Ji, Tao; Guo, Wei

    2017-12-27

    Hip dislocation is a major complication of total femoral prosthetic reconstruction (TFR) after femoral tumor resection. Hip dislocation can occur because of inadequate functional abductor musculature, inadequate hip capsule repair, or a long lever arm after total femur replacement. To eliminate the negative effects of these factors on the risk of hip dislocation, the use of artificial ligaments may help to increase the stability of the hip joint. We aimed to determine whether application of an artificial ligament would improve limb function and active range of movement (ROM) after TFR. Fifty-eight patients who underwent femoral tumor resection and TFR were included. A band-shaped artificial ligament was wrapped spirally around the proximal site of the total femur prosthesis for periacetabular soft tissue reconstruction in 12 patients. The other 46 patients did not consent to receiving the artificial ligament. Complications including hip dislocation and infection, limb function, and active hip ROM were compared between patients who did and did not receive the artificial ligament. The hip dislocation rate was lower in the patients who received the artificial ligament. The risk of deep infection did not differ between groups. The group that received the ligament also achieved better limb function and active ROM on flexion and abduction. Patients treated with total femur resection and endoprosthetic replacement with an artificial ligament for periacetabular soft tissue reconstruction had a more stable hip joint, better limb function, and greater active hip ROM than did patients who did not receive an artificial ligament. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Patient and implant survival following joint replacement because of metastatic bone disease

    DEFF Research Database (Denmark)

    Sørensen, Michala S; Gregersen, Kristine G; Grum-Schwensen, Tomas

    2013-01-01

    Patients suffering from a pathological fracture or painful bony lesion because of metastatic bone disease often benefit from a total joint replacement. However, these are large operations in patients who are often weak. We examined the patient survival and complication rates after total joint...

  15. Does endoprosthetic replacement of large joints improve quality of life in patients with rheumatoid arthritis?

    Directory of Open Access Journals (Sweden)

    Nadezhda Alekseevna Savenkova

    2011-01-01

    Conclusion. The majority of patients had not initially received adequate disease-modifying anti-inflammatory therapy for many years. Endoprosthetic replacement of the lower limb joints in the first 6 months after surgery improved the functional capacity of the operated joint, by increasing QL in the patients as a whole. There was no substantial decrease in global disease activity 6 months following surgery.

  16. Differences in the stress distribution in the distal femur between patellofemoral joint replacement and total knee replacement: a finite element study

    NARCIS (Netherlands)

    van Jonbergen, H.P.; Innocenti, B.; Gervasi, G.L.; Labey, L.; Verdonschot, N.J.

    2012-01-01

    BACKGROUND: Patellofemoral joint replacement is a successful treatment option for isolated patellofemoral osteoarthritis. However, results of later conversion to total knee replacement may be compromised by periprosthetic bone loss. Previous clinical studies have demonstrated a decrease in distal

  17. Total hip replacement for Mseleni Joint Disease undertaken in a ...

    African Journals Online (AJOL)

    The objective of this project was to ascertain whether it is reasonable to perform specialist surgery for Mseleni Joint Disease (MJD) in a rural hospital by assessing the medium-term outcome of surgery for MJD performed at Mseleni. The study was designed as a review of patients at Mseleni Hospital in rural KwaZulu Natal, ...

  18. Finite element analysis of artificial hip joint movement during human activities

    NARCIS (Netherlands)

    Saputra, Eko; Budiwan, I.; Jamari, Jamari; van der Heide, Emile

    2014-01-01

    The range of motion of artificial hip joint during human activities, measured from the postoperative total hip arthroplasty patients, has been reported previously. There were two human activities discussed, i.e. Western-style and Japanese-style. This paper analyzes the hip joint movement during

  19. Breathing zone concentrations of methylmethacrylate monomer during joint replacement operations

    DEFF Research Database (Denmark)

    Darre, E; Jørgensen, L G; Vedel, P

    1992-01-01

    By use of a methylmethacrylate (MMA) Dräger tube and bellow bump, the breathing zone concentrations of MMA monomer were measured for the operating surgeon during cementation of the components of hip and knee joint prostheses. The highest recordings (50-100 p.p.m.) were encountered during...... cementation of the acetabular cups with conventional polymethylmethacrylate cement. Such exposure could be eliminated by the use of personal protection equipment, local punctual field suction or change to a MMA/n-decylmethacrylate/isobornylmethacrylate bone cement....

  20. Breathing zone concentrations of methylmethacrylate monomer during joint replacement operations

    DEFF Research Database (Denmark)

    Darre, E; Jørgensen, L G; Vedel, P

    1992-01-01

    By use of a methylmethacrylate (MMA) Dräger tube and bellow bump, the breathing zone concentrations of MMA monomer were measured for the operating surgeon during cementation of the components of hip and knee joint prostheses. The highest recordings (50-100 p.p.m.) were encountered during cementat...... cementation of the acetabular cups with conventional polymethylmethacrylate cement. Such exposure could be eliminated by the use of personal protection equipment, local punctual field suction or change to a MMA/n-decylmethacrylate/isobornylmethacrylate bone cement....

  1. Restriction in participation in leisure activities after joint replacement: an exploratory study.

    Science.gov (United States)

    Wylde, Vikki; Livesey, Christine; Blom, Ashley W

    2012-03-01

    currently, assessment of outcomes after joint replacement is predominantly centred on impairment and activity limitation (e.g. walking), with little consideration of participation restriction. structured telephone interviews about participation in leisure activities were conducted with 56 total hip replacement (THR) and 60 total knee replacement (TKR) patients before and 1 year after joint replacement. before surgery, THR patients participated in 209 leisure activities, with an average of four leisure activities per person. TKR patients participated in 171 leisure activities, with an average of three leisure activities per person. The leisure activities were coded into four categories: sports/exercise, hobbies, social activities and holidays. Between 89 and 95% of leisure activities were rated as important by THR and TKR patients prior to surgery. Before surgery, THR patients rated 82% of leisure activities as difficult to perform because of joint problems, which decreased to 25% of leisure activities by 1-year after surgery. TKR patients rated 86% of leisure activities as difficult to perform because of joint problems, which decreased to 32% after surgery. this research highlights that participation in leisure activities is important to patients undergoing joint replacement, but that approximately a quarter of patients are unable to perform their valued leisure activities after surgery.

  2. Rates of hip and knee joint replacement amongst different ethnic groups in England: an analysis of National Joint Registry data.

    Science.gov (United States)

    Smith, M C; Ben-Shlomo, Y; Dieppe, P; Beswick, A D; Adebajo, A O; Wilkinson, J M; Blom, A W

    2017-04-01

    Despite a health care system that is free at the point of delivery, ethnic minorities may not always get care equitable to that of White patients in England. We examined whether ethnic differences exist in joint replacement rates and surgical practice in England. 373,613 hip and 428,936 knee National Joint Registry (NJR) primary replacement patients had coded ethnicity in Hospital Episode Statistics (HES). Age and gender adjusted observed/expected ratios of hip and knee replacements amongst ethnic groups were compared using indirect standardisation. Associations between ethnic group and type of procedure were explored and effects of demographic, clinical and hospital-related factors examined using multivariable logistic regression. Adjusted standardised observed/expected ratios were substantially lower in Blacks and Asians than Whites for hip replacement (Blacks 0.33 [95% CI, 0.31-0.35], Asians 0.20 [CI, 0.19-0.21]) and knee replacement (Blacks 0.64 [CI, 0.61-0.67], Asians 0.86 % [CI, 0.84-0.88]). Blacks were more likely to receive uncemented hip replacements (Blacks 52%, Whites 37%, Asians 44%; P replacements than Whites (men 10% vs 15%, P = 0.001; women 6% vs 14%, P replacement (OR 1.43 [CI, 1.11-1.84]). In England, hip and knee replacement rates and prosthesis type given differ amongst ethnic groups. Whether these reflect differences in clinical need or differential access to treatment requires urgent investigation. Copyright © 2017. Published by Elsevier Ltd.

  3. Wear debris. An environmental issue in total joint replacement.

    Science.gov (United States)

    Manley, M T; Serekian, P

    1994-01-01

    There is a growing concern that osteolytic lesions, often adjacent to otherwise stable implants, are a recent phenomenon caused by some recent change in polyethylene, metal, or other aspect of the total hip construction. This study investigates the possibility that bearings and modular connections used in modern hip replacements are an unappreciated source of particulate debris. Measurements taken from contemporary femoral bearings show a significant mismatch in both surface finish and sphericity of mating metal and polyethylene components, with sphericity of inserts being much worse then sphericity of femoral heads. The tolerances for sphericity of polyethylene inserts were further changed by the placement of an insert into its metal shell. Hip simulator tests of assembled inserts and shells showed greater polyethylene weight loss for metal-backed shells than for inserts alone. Bending and torsional tests of metal/metal modular connections showed that dynamic loads can release large numbers of debris particles from taper junctions. Because osteolytic lesions clearly are associated with overload of tissue by debris particles, the design, manufacture, and tolerances of modular connections in total hip replacement all seem to require reevaluation.

  4. Preoperative Risk Factors for Subsyndromal Delirium in Older Adults Who Undergo Joint Replacement Surgery.

    Science.gov (United States)

    Denny, Dawn L; Lindseth, Glenda

    Older adults with subsyndromal delirium have similar risks for adverse outcomes following joint replacement surgery as those who suffer from delirium. This study examined relationships among subsyndromal delirium and select preoperative risk factors in older adults following major orthopaedic surgery. Delirium assessments of a sample of 62 adults 65 years of age or older were completed on postoperative Days 1, 2, and 3 following joint replacement surgery. Data were analyzed for relationships among delirium symptoms and the following preoperative risk factors: increased comorbidity burden, cognitive impairment, fall history, and preoperative fasting time. Postoperative subsyndromal delirium occurred in 68% of study participants. A recent fall history and a longer preoperative fasting time were associated with delirium symptoms (p ≤ .05). Older adults with a recent history of falls within the past 6 months or a longer duration of preoperative fasting time may be at higher risk for delirium symptoms following joint replacement surgery.

  5. Does the immune system play a role in loosening and osteolysis of total joint replacements?

    Science.gov (United States)

    Goodman, S B

    1996-01-01

    Total joint replacement is a highly successful surgical procedure with an excellent outcome over many years. However, because this procedure is now being performed in younger patients, and because the average age of our population continues to increase, greater expectations have been placed on joint implants in the hope that they will last forever. Aseptic loosening and osteolysis of total joint replacements are the main processes limiting long-term implant survival. This paper focuses on the possible role of immunological mechanisms in the processes of loosening and osteolysis of joint replacements, with special emphasis on polymeric materials. This topic is very controversial: In vitro experiments and in vivo studies in animals and humans are reviewed and provide evidence for both sides of the debate. In some patients, immunological processes appear to be activated after a total joint replacement has been implanted. Specific materials or their by-products might function as haptens and elicit a T-lymphocyte-mediated, delayed hypersensitivity reaction. Many factors probably are important, including the genetic makeup and immune competence of the patient, prior exposure to the same or similar materials, degree of exposure (rate of generation of particles and the efficacy of clearance mechanisms), and characteristics of the particles themselves.

  6. [Partial and total joint replacement in femur head necrosis].

    Science.gov (United States)

    Fink, B; Rüther, W

    2000-05-01

    In literature, the results of hip arthroplasty in patients with avascular osteonecrosis of the femoral head vary. The main reason may be the nonhomogeneous patient groups concerning etiology of the femoral head necrosis (FHN). Analyzing the results of hip endoprosthesis in relation to the etiology of FHN leads to the assumption that steroid-induced FHN and FHN with underlying systemic bone diseases (renal osteodystrophy, sickle-cell hemoglobinopathy) have the highest loosening rates. Diseases with immunosuppressive medication and sickle-cell hemoglobinopathy have the highest risk of joint infection. Therefore etiology plays an important role in the long-term results of hip endoprostheses in FHN. Modern cement techniques of the second generation and new non-cemented total hip endoprostheses seem to have better results than older prostheses and cement techniques. We followed-up 52 non-cemented thrust plate prostheses in 45 patients with FHN, prospectively, for at least 2 years (3.7 +/- 1.6 years). The revision rate was 9.6% (two aseptic loosenings in one patient with renal osteodystrophy and one patient with alcohol abuse, as well as three late infections in one patient with alcohol abuse and two patients with renal osteodystrophy). Additionally, five prostheses showed radiologic lines of a minimum of 2 mm. Future studies with longer follow-up are needed to find out whether these prosthetic designs with proximal fixation of the femoral component preserving the diaphysial bone have advantages in young FHN patients.

  7. Quantification of structural changes of UHMWPE components in total joint replacements.

    Science.gov (United States)

    Fulin, Petr; Pokorny, David; Slouf, Miroslav; Nevoralova, Martina; Vackova, Tatana; Dybal, Jiri; Pilar, Jan

    2014-03-28

    At present time the number of implantations of joint replacements as well as their revisions increases. Higher demands are required on the quality and longevity of implants. The aim of this work was to determine the degree of oxidative degradation and the amount of free/residual radicals in selected ultra-high molecular weight polyethylene (UHMWPE) components of the joint replacements and demonstrate that the measured values are closely connected with quality and lifetime of the polymer components. We tested both new (4 samples) and explanted (4 samples) UHMWPE polymers for total joint replacements. The samples were characterized by infrared spectroscopy (IR), electron spin resonance (ESR) and microhardness (MH) test. The IR measurements yielded the values of oxidation index and trans-vinylene index. The ESR measurements gave the free radicals concentration. In the group of new polyethylene components, we found oxidation index values ranging from 0.00-0.03 to 0.24. The trans-vinylene index values ranged from 0.044 to 0.080. The value of free radical concentration was zero in virgin and also in sample of Beznoska Company and non-zero in the other samples. In the group of explanted components, the measured values were associated with their history, micromechanical properties and performance in vivo. We demonstrated that measuring of oxidative damage may help the orthopaedic surgeon in estimating the quality of UHMWPE replacement component and thus radically to avoid early joint replacement failure due to worse polyethylene quality.

  8. [Preparation and biomechanics study of biological artificial knee joint prosthesis with stereo mesh surface in rabbit].

    Science.gov (United States)

    Liu, Jianhua; Xu, Dongliang; Yu, Shiming; Hu, Junyong; Chen, Jianwei; Lei, Lei; Li, Zhanchun; Zeng, Xianshang

    2009-04-01

    To develop a kind of biological artificial knee joint prosthesis with stereo mesh surface for rabbit, to observe its function after being implanted into rabbit knee joint and to evaluate its biomechanical property. Thirty adult New Zealand rabbits were randomized into experimental and control groups (n=15), total left knee arthroplasty was performed in both groups, no patella replacement was performed. Biological artificial knee joint prosthesis with stereo mesh surface was self-designed. The adjacent 4/5 surface of femur and tibia stem of the prosthesis was covered by stainless steel stereo mesh, the inner surface of femur condyles and tibia plateau was welded with two layers of stainless steel stereo mesh, then the prosthesis underwent biological fixation in the experimental group. Meanwhile, prosthesis having smooth marrow internal stem, femoral condyle and tibial plateau internal surface and sharing the same shape and size with the experimental group were prepared and fixed with bone cement in the control group. The postoperative general condition of animal was observed. At 1, 3 and 6 months after operation, the rabbits were killed for gross observation, X-ray examination was conducted to observe the fixation condition of prosthesis and healing condition, the range of motion (ROM) of knee joints was tested, biomechanics test was carried out and the maximum shear strength of prosthesis bone interface was calculated. In each group, there was 1 rabbit died and new one was added during the second experiment. The others survived till the end of the experiment and crawled normally 7 days after operation. For the excellent and good rate concerning the recovery of ROM of the knee joint at 1, 3 and 6 months after operation, the experimental group was 60%, 80% and 80%, respectively, and the control group was 60%, 80% and 60%, respectively, indicating there were no significant differences between two groups (P > 0.05). For the experimental group, the gross observation

  9. Evidence-base for aspirin as venous thromboembolic prophylaxis following joint replacement.

    Science.gov (United States)

    Jameson, S S; Baker, P N; Deehan, D J; Port, A; Reed, M R

    2014-05-01

    The National Institute for Health and Clinical Excellence (NICE) has thus far relied on historical data and predominantly industry-sponsored trials to provide evidence for venous thromboembolic (VTE) prophylaxis in joint replacement patients. We argue that the NICE guidelines may be reliant on assumptions that are in need of revision. Following the publication of large scale, independent observational studies showing little difference between low-molecular-weight heparins and aspirin, and recent changes to the guidance provided by other international bodies, should NICE reconsider their recommendations? Cite this article: Bone Joint Res 2014;3:146-9. ©2014 The British Editorial Society of Bone & Joint Surgery.

  10. Tribological performance of the biological components of synovial fluid in artificial joint implants

    Science.gov (United States)

    Ghosh, Subir; Choudhury, Dipankar; Roy, Taposh; Moradi, Ali; Masjuki, H H; Pingguan-Murphy, Belinda

    2015-01-01

    The concentration of biological components of synovial fluid (such as albumin, globulin, hyaluronic acid, and lubricin) varies between healthy persons and osteoarthritis (OA) patients. The aim of the present study is to compare the effects of such variation on tribological performance in a simulated hip joint model. The study was carried out experimentally by utilizing a pin-on-disk simulator on ceramic-on-ceramic (CoC) and ceramic-on-polyethylene (CoP) hip joint implants. The experimental results show that both friction and wear of artificial joints fluctuate with the concentration level of biological components. Moreover, the performance also varies between material combinations. Wear debris sizes and shapes produced by ceramic and polyethylene were diverse. We conclude that the biological components of synovial fluid and their concentrations should be considered in order to select an artificial hip joint to best suit that patient. PMID:27877822

  11. Use of Tranexamic Acid during Total Endoprosthetic Replacement of the Hip Joint

    Directory of Open Access Journals (Sweden)

    D. D. Selivanov

    2010-01-01

    Full Text Available Objective: to evaluate the blood-saving activity, efficacy, and safety of tranexamic acid. Subjects and methods. Thirty-seven patients allocated into two groups were enrolled in the study of the efficacy of tranexamic acid as an agent in reducing blood loss during hip joint replacement. Group 2 patients were injected tranexamic acid, 10 mg/kg body weight, 20—30 minutes before and 3 hours after surgery in the same dosage. This resulted in a significant (48.5% reduction in total blood loss (from 1089.6 to 560.8 ml (p<0.05. No tranexamic acid-induced complications were found. The administration of tranexamic acid during total endoprosthetic replacement of the hip joint could reduce blood loss by 35 and 59.4% in the intraoperative and postoperative periods, respectively, and total blood loss by 48.4%. The use of tranexamic acid allows one to refuse transfusion of blood components during total endoprosthetic replacement of the hip joint. Key words: hip joint replacement, blood loss, tranexamic acid.

  12. Numerical Modelling of the Weight-Bearing Total Knee Joint Replacement and Usage in Practice

    Czech Academy of Sciences Publication Activity Database

    Daněk, Josef; Nedoma, Jiří; Hlaváček, Ivan; Vavřík, P.; Denk, F.

    2007-01-01

    Roč. 76, č. 1-3 (2007), s. 49-56 ISSN 0378-4754 R&D Projects: GA MPO FT-TA/087 Institutional research plan: CEZ:AV0Z10300504 Keywords : total knee joint replacement * contact problem * non-overlapping domain decomposition method Subject RIV: BA - General Mathematics Impact factor: 0.738, year: 2007

  13. Docking Robustness of Patient Specific Surgical Guides for Joint Replacement Surgery

    NARCIS (Netherlands)

    Mattheijer, Joost; Herder, Just L.; Tuijthof, Gabrielle J. M.; Valstar, Edward R.

    2015-01-01

    In joint replacement surgery, patient specific surgical guides (PSSGs) are used for accurate alignment of implant components. PSSGs are designed preoperatively to have a geometric fit with the patient's bone such that the incorporated guidance for drilling and cutting is instantly aligned. The

  14. Porous polymers for repair and replacement of the knee joint meniscus and articular cartilage

    NARCIS (Netherlands)

    Klompmaker, Jan

    1992-01-01

    The studies presented here were initiated to answer a variety of questions concerning firstly the repair and replacement of the knee joint meniscus and, secondly, the repair of full-thickness defects of articular cartilage. AIMS OF THE STUDIES I To assess the effect of implantation of a porous

  15. Micromechanical properties of one-step and sequentially crosslinked UHMWPEs for total joint replacements

    Czech Academy of Sciences Publication Activity Database

    Šlouf, Miroslav; Vacková, Taťana; Nevoralová, Martina; Pokorný, D.

    2015-01-01

    Roč. 41, February (2015), s. 191-197 ISSN 0142-9418 R&D Projects: GA MZd NT12229; GA TA ČR TA01011406; GA ČR(CZ) GA14-17921S Institutional support: RVO:61389013 Keywords : UHMWPE * joint replacement * microindentation hardness testing Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.350, year: 2015

  16. Femoral component rotation in patellofemoral joint replacement: a study protocol for a prospective observational study.

    Science.gov (United States)

    Westerbeek, Robin E; Derks, Rosalie P H; Zonneveld, Bas J G L; van Jonbergen, Hans-Peter W

    2015-01-01

    Patellofemoral joint replacement is a successful treatment option for isolated patellofemoral osteoarthritis. The short and mid-term outcomes are related to malposition and unexplained pain. Whether external rotation of the femoral component in isolated patellofemoral joint replacement is required is unclear. The primary aim of this study is to determine the CT-measured femoral component rotation of patellofemoral joint replacement relative to the transepicondylar axis. The secondary aim is to correlate the CT-measured femoral component rotation with the clinical outcomes at 1-year follow-up as assessed with the KOOS questionnaire. We designed a prospective observational study with medical research ethics committee and institutional review board approval. A total of 40 patients who will be treated with patellofemoral joint replacement for isolated patellofemoral osteoarthritis will be included. Intra-operatively, rotation of the femoral component will be assessed using anatomical landmarks including the epicondylar axis, Whiteside's line, and lower leg axis. The aim is to insert the femoral component between 3 and 6 degrees external rotation relative to the transepicondylar axis. Two experienced musculoskeletal radiologists will measure the angle between the transepicondylar axis and the femoral component, two to three days after surgery. The primary outcome is the CT-based femoral component rotation of the prosthesis relative to the transepicondylar axis. The secondary outcome is the patient reported KOOS questionnaire at 1-year follow-up. Successful completion of this study will provide data on the actual amount of femoral component rotation in patellofemoral joint replacement, and its relationship with clinical results. (Netherlands Trial Register NTR4175).

  17. Redesigning a joint replacement program using Lean Six Sigma in a Veterans Affairs hospital.

    Science.gov (United States)

    Gayed, Benjamin; Black, Stephen; Daggy, Joanne; Munshi, Imtiaz A

    2013-11-01

    In April 2009, an analysis of joint replacement surgical procedures at the Richard L. Roudebush Veterans Affairs Medical Center, Indianapolis, Indiana, revealed that total hip and knee replacements incurred $1.4 million in non-Veterans Affairs (VA) care costs with an average length of stay of 6.1 days during fiscal year 2008. The Joint Replacement Program system redesign project was initiated following the Vision-Analysis-Team-Aim-Map-Measure-Change-Sustain (VA-TAMMCS) model to increase efficiency, decrease length of stay, and reduce non-VA care costs. To determine the effectiveness of Lean Six Sigma process improvement methods applied in a VA hospital. Perioperative processes for patients undergoing total joint replacement were redesigned following the VA-TAMMCS model--the VA's official, branded method of Lean Six Sigma process improvement. A multidisciplinary team including the orthopedic surgeons, frontline staff, and executive management identified waste in the current processes and initiated changes to reduce waste and increase efficiency. Data collection included a 1-year baseline period and a 20-month sustainment period. The primary endpoint was length of stay; a secondary analysis considered non-VA care cost reductions. Length of stay decreased 36% overall, decreasing from 5.3 days during the preproject period to 3.4 days during the 20-month sustainment period (P Six Sigma process improvement initiatives in a surgical practice, producing a 36% sustained reduction in length of stay and completely eliminating non-VA care for total hip and knee replacements while increasing total joint replacement volume at this medical center.

  18. Acupuncture provides short-term pain relief for patients in a total joint replacement program.

    Science.gov (United States)

    Crespin, Daniel J; Griffin, Kristen H; Johnson, Jill R; Miller, Cynthia; Finch, Michael D; Rivard, Rachael L; Anseth, Scott; Dusek, Jeffery A

    2015-06-01

    Given the risks of opioid medications, nonpharmacological strategies should be considered for total joint replacement patients. We investigated acupuncture as an adjunct therapy for postsurgical pain management in a total joint replacement program by examining which total hip and knee replacement patients elected to receive acupuncture and the effect of acupuncture on short-term pain. A total joint replacement program using fast-track physiotherapy offered elective postsurgical acupuncture to all patients, at no additional cost, as an adjunct therapy to opioids for pain management. The Joint Replacement Center at Abbott Northwestern Hospital, a 630-bed teaching and specialty hospital in Minneapolis, Minnesota from 2010 to 2012. Our sample included 2,500 admissions of total hip (THR) and total knee replacement (TKR) patients. Self-reported pain was assessed before and after acupuncture using a 0-10 scale and categorized as none/mild (0-4) and moderate/severe pain (5-10). Seventy-five percent of admissions included acupuncture. Women (Odds Ratio: 1.48, 95% Confidence Interval (CI): 1.22, 1.81) had higher odds of receiving acupuncture compared to men, and nonwhite patients (Odds Ratio: 0.55, 95% CI: 0.39, 0.78) had lower odds of receiving acupuncture compared to white patients. Average short-term pain reduction was 1.91 points (95% CI: 1.83, 1.99), a 45% reduction from the mean prepain score. Forty-one percent of patients reported moderate/severe pain prior to receiving acupuncture, while only 15% indicated moderate/severe pain after acupuncture. Acupuncture may be a viable adjunct to pharmacological approaches for pain management after THR or TKR. Wiley Periodicals, Inc.

  19. [Radiodiagnosis and knee joint replacement in hemophilic arthropathies in Kazakhstan residents].

    Science.gov (United States)

    Abdrakhmanova, Zh S; Rakhimzhanova, R I; Zhunusov, E T; Pivovarova, I A; Sultangereev, A B; Zagurskaia, E A; Kaldybaev, M M; Zhansagimova, Z S

    2014-01-01

    To assess complex radiodiagnosis and highly specialized medical care as knee joint replacement (KJR) to patients with hemophilic arthropathies (HA) who live in the Republic of Kazakhstan. The results of examination and treatment were analyzed in 40 patients with knee HA who were treated at the specialized Polytrauma Unit, Republican Research Center for Emergency Health Care. All patients with hemophilia A underwent joint X-ray study, computed tomography and magnetic resonance imaging (MRI), X-ray densitometry and ultrasound osteometry on admission and after KJR. Joint X-ray studies and computed tomography revealed that all the patients had Grades II-III arthroses with severe dysfunction of joints, their multiple involvements of different grades, which depended on the rate of recurrent hemarthrosis. Ultrasound study (USS) is the only mini-invasive method to control surgical hemostasis in hemophiliac patients after KJR. Osteodensitometry revealed osteopenia and osteoporosis in all the patients with hemophilia, which was a basis for prescribing calcium preparations in the early postoperative period for the prevention of instability of endoprosthetic components. We elaborated an algorithm for combination treatment in HA patients, which involved knee joint replacement. Highly specialized medical care to hemophilic patients and active introduction of the early surgical rehabilitation of the affected joint in their combination treatment contributed to the increased number of positive results, by restoring the quality of life in the patients: excellent, good, and satisfactory anatomic and functional results were obtained in 26.7, 51.1, and 22.2%, respectively. USS and MRI could evaluate joint changes in HA in detail, which plays an important role in the estimation of the course time of the disease, in the planning of endoprosthetic replacement, and in the timely prevention of severe complications of HA. Osteodensitometry makes it possible to monitor bone mineral density

  20. A prospective study on the risk of glove fingertip contamination during draping in joint replacement surgery.

    Science.gov (United States)

    Makki, D; Deierl, K; Pandit, A; Trakru, S

    2014-09-01

    The aim of this prospective study was to investigate the risk of contamination of surgical gloves during preparation and draping in joint replacement surgery. During 46 hip and knee replacement procedures, the gloves of orthopaedic consultants (n=5) and registrars (n=3) were assessed for contamination immediately after draping by impression of gloved fingers on blood agar. Contamination was evaluated by the surgeon's grade, the type of procedure, the role of the assistant and the dominance of the hand. A total of 125 pairs of top gloves were examined (79 pairs from registrars and 46 pairs from consultants). Bacterial contamination was isolated on 19 pairs (15.2%) (16 pairs from registrars and 3 pairs from consultants, p=0.04). Coagulase negative staphylococci were the main isolates and contamination was considered low in all cases (1-5 colonies). Contamination was seen more on the dominant hand (16 gloves from dominant hands and 6 from non-dominant hands, p=0.04), on the index finger and thumb. More contaminated gloves were seen in hip arthroplasty procedures (16 pairs from total hip replacements vs 3 pairs from total knee replacements, p=0.02). Contamination of glove fingertips during draping in joint replacement procedures is more likely to occur among junior surgeons, in hip rather than knee arthroplasty procedures and on the dominant hand. It is therefore essential that surgeons of different grades replace gloves used in draping to avoid exposing patients to the risk of infection.

  1. Design and simulation of a cable-pulley-based transmission for artificial ankle joints

    Science.gov (United States)

    Liu, Huaxin; Ceccarelli, Marco; Huang, Qiang

    2016-06-01

    In this paper, a mechanical transmission based on cable pulley is proposed for human-like actuation in the artificial ankle joints of human-scale. The anatomy articular characteristics of the human ankle is discussed for proper biomimetic inspiration in designing an accurate, efficient, and robust motion control of artificial ankle joint devices. The design procedure is presented through the inclusion of conceptual considerations and design details for an interactive solution of the transmission system. A mechanical design is elaborated for the ankle joint angular with pitch motion. A multi-body dynamic simulation model is elaborated accordingly and evaluated numerically in the ADAMS environment. Results of the numerical simulations are discussed to evaluate the dynamic performance of the proposed design solution and to investigate the feasibility of the proposed design in future applications for humanoid robots.

  2. Does the Risk Assessment and Prediction Tool Predict Discharge Disposition After Joint Replacement?

    DEFF Research Database (Denmark)

    Hansen, Viktor J.; Gromov, Kirill; Lebrun, Lauren M

    2015-01-01

    therefore be of use. The Risk Assessment and Prediction Tool (RAPT) is a preoperative survey constructed to predict discharge disposition after total joint arthroplasty (TJA). The RAPT was developed and tested on a population of Australian patients undergoing joint replacement, but its validity in other...... data, including discharge disposition, in a dedicated database on a secure server. The database was queried by the nursing case manager to retrieve the RAPT scores of all patients captured during this time period. Binary logistic regression was used to analyze the scores and determine predictive...

  3. A personalized 3D-printed prosthetic joint replacement for the human temporomandibular joint: From implant design to implantation.

    Science.gov (United States)

    Ackland, David C; Robinson, Dale; Redhead, Michael; Lee, Peter Vee Sin; Moskaljuk, Adrian; Dimitroulis, George

    2017-05-01

    Personalized prosthetic joint replacements have important applications in cases of complex bone and joint conditions where the shape and size of off-the-shelf components may not be adequate. The objective of this study was to design, test and fabricate a personalized 3D-printed prosthesis for a patient requiring total joint replacement surgery of the temporomandibular joint (TMJ). The new 'Melbourne' prosthetic TMJ design featured a condylar component sized specifically to the patient and fixation screw positions that avoid potential intra-operative damage to the mandibular nerve. The Melbourne prosthetic TMJ was developed for a 58-year-old female recipient with end-stage osteoarthritis of the TMJ. The load response of the prosthesis during chewing and a maximum-force bite was quantified using a personalized musculoskeletal model of the patient's masticatory system developed using medical images. The simulations were then repeated after implantation of the Biomet Microfixation prosthetic TMJ, an established stock device. The maximum condylar stresses, screw stress and mandibular stress at the screw-bone interface were lower in the Melbourne prosthetic TMJ (259.6MPa, 312.9MPa and 198.4MPa, respectively) than those in the Biomet Microfixation device (284.0MPa, 416.0MPa and 262.2MPa, respectively) during the maximum-force bite, with similar trends also observed during the chewing bite. After trialing surgical placement and evaluating prosthetic TMJ stability using cadaveric specimens, the prosthesis was fabricated using 3D printing, sterilized, and implanted into the female recipient. Six months post-operatively, the prosthesis recipient had a normal jaw opening distance (40.0 mm), with no complications identified. The new design features and immediate load response of the Melbourne prosthetic TMJ suggests that it may provide improved clinical and biomechanical joint function compared to a commonly used stock device, and reduce risk of intra-operative nerve damage

  4. Evidence-base for aspirin as venous thromboembolic prophylaxis following joint replacement

    OpenAIRE

    Jameson, S. S.; Baker, P. N.; Deehan, D. J.; Port, A.; Reed, M. R.

    2014-01-01

    The National Institute for Health and Clinical Excellence (NICE) has thus far relied on historical data and predominantly industry-sponsored trials to provide evidence for venous thromboembolic (VTE) prophylaxis in joint replacement patients. We argue that the NICE guidelines may be reliant on assumptions that are in need of revision. Following the publication of large scale, independent observational studies showing little difference between low-molecular-weight heparins and aspirin, and rec...

  5. Wear behaviour of UHMWPE reinforced by carbon nanofiller and paraffin oil for joint replacement.

    Science.gov (United States)

    Yousef, Samy; Visco, Annamaria; Galtieri, Giovanna; Nocita, Davide; Espro, Claudia

    2017-04-01

    The majority of artificial joints incorporate biomedical grade Ultra High Molecular Weight Poly Ethylene (UHMWPE), whose wear is considered most important in controlling service time of the whole joint. The aim of this work was to improve wear resistance of UHMWPE through the addition of 0.5-2.0wt% of Carbon Nano Filler (CNF) and 2% wt of Paraffin Oil (PO) using ball milling (BM) and extrusion techniques (EX). The wear tests on these nanocomposites were conducted by a pin on disc in dry (air) and wet media (simulated synovial fluid or artificial lubricant, and bovine synovial fluid or natural lubricant). Mechanical tests (tensile and hardness), physical analysis (calorimetric, density, wet ability, roughness) and morphological observations were also performed. The experimental results showed that natural lubricant provides the greatest reduction in wear rate while the largest one occurred in air. Furthermore, the BM mixed nanocomposites with a filler load of 1.0% exhibited the best wear resistance among all the samples with an improvement of 42%, 64% and 83% in air, artificial and natural lubricant, respectively. This is due to its higher ductility and thermal features, and lower wet ability in the two lubricants. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Mixed reality simulation of rasping procedure in artificial cervical disc replacement (ACDR) surgery.

    Science.gov (United States)

    Halic, Tansel; Kockara, Sinan; Bayrak, Coskun; Rowe, Richard

    2010-10-07

    Until quite recently spinal disorder problems in the U.S. have been operated by fusing cervical vertebrae instead of replacement of the cervical disc with an artificial disc. Cervical disc replacement is a recently approved procedure in the U.S. It is one of the most challenging surgical procedures in the medical field due to the deficiencies in available diagnostic tools and insufficient number of surgical practices For physicians and surgical instrument developers, it is critical to understand how to successfully deploy the new artificial disc replacement systems. Without proper understanding and practice of the deployment procedure, it is possible to injure the vertebral body. Mixed reality (MR) and virtual reality (VR) surgical simulators are becoming an indispensable part of physicians' training, since they offer a risk free training environment. In this study, MR simulation framework and intricacies involved in the development of a MR simulator for the rasping procedure in artificial cervical disc replacement (ACDR) surgery are investigated. The major components that make up the MR surgical simulator with motion tracking system are addressed. A mixed reality surgical simulator that targets rasping procedure in the artificial cervical disc replacement surgery with a VICON motion tracking system was developed. There were several challenges in the development of MR surgical simulator. First, the assembly of different hardware components for surgical simulation development that involves knowledge and application of interdisciplinary fields such as signal processing, computer vision and graphics, along with the design and placements of sensors etc . Second challenge was the creation of a physically correct model of the rasping procedure in order to attain critical forces. This challenge was handled with finite element modeling. The third challenge was minimization of error in mapping movements of an actor in real model to a virtual model in a process called

  7. [Research on surface modification and bio-tribological properties of artificial joint].

    Science.gov (United States)

    Pan, Yusong; Wang, Jing; Ding, Guoxin

    2012-06-01

    The bio-tribological properties of an artificial joint can be obviously improved by surface modification technologies. In this paper, the benefits and disadvantages of various surface modification methods-such as surface coating, plasma treatment, surface texture and surface grafting modification-are discussed. The aim of surface coating and/or plasma treatment is to improve the surface hardness of the materials, thus enhancing the wear resistance of artificial joints. However, these technologies do not effectively alleviate stress concentration of material in the short times in which artificial joints bear physiological impact load, resulting in easy fracture. Surface texture serves mainly to improve the lubrication properties through micro-concavities on the material surface for storage lubricant. Surface texturing can realize improvements in bio-tribological properties, but it does not enhance the impact resistance of the joint. Surface grafting modification is implemented mainly by grafting hydrophilic or other specific functional groups to improve the surface hydrophilicity and wetability, thus enhancing lubricating performance and reducing the coefficient of friction.

  8. Comprehensive Care for Joint Replacement (CJR) Bundle Expense in Perioperative Pain Management.

    Science.gov (United States)

    Bear, Susan D

    The implementaion of the Comprehensive Care for Joint Replacement (CJR) model has necessitated value-focused care for a 90-day period. Pain management in joint arthroplasty therefore represents a focused opportunity to achieve lasting change in the delivery of care. To be successful, orthopedic surgeons must integrate approaches that take into account administration route and therapy duration, and various combinations thereof, to achieve improved longer term outcomes for joint arthroplasty patients. In addition, pain management choices must be based on value and not on simple costs, as patient satisfaction scores affect CJR repayments. While the postdischarge time period poses the highest risk, improved collaboration with post-acute care providers, such as hospitalists, pharmacists, and rehabilitation facilities will be crucial to addressing patient comorbidities and ensuring optimal outcomes post-surgery. Furthermore, multimodal pain management strategies associated with optimal pain control and shorter hospital stays are valuable in achieving improved outcome and financial metrics.

  9. Intrinsic constraint of unlinked total elbow replacements--the ulnotrochlear joint.

    Science.gov (United States)

    Kamineni, S; O'Driscoll, S W; Urban, M; Garg, A; Berglund, L J; Morrey, B F; An, K N

    2005-09-01

    Many unlinked total elbow replacement designs with radically differing articular geometries exist, suggesting that there is no consensus regarding an optimal design. A feature inherent to the articular design is the intrinsic constraint afforded to the joint by the implant. Our aim was to compare the intrinsic constraints of unlinked implants with that of the normal ulnotrochlear joint. We tested twelve cadaveric ulnotrochlear joints with a custom-made multiple-axis materials testing machine. With compressive loads ranging from 10 to 100 N, the joints were moved in either valgus or varus directions at 90 degrees of flexion. The ulnotrochlear components from a single example of five medium-sized unlinked elbow replacements (Ewald, Kudo, Pritchard ERS, Sorbie-Questor, and Souter-Strathclyde) were also tested. The recorded measurements included the torques and forces, angular displacement, and axial displacement of the humerus relative to the ulna. In general, the peak torque and the constraint ratio significantly increased with increasing compressive load for the implants as well as for the normal elbow. In valgus displacement, the Souter-Strathclyde implant had the highest and the Sorbie-Questor had the smallest peak torque and the Souter-Strathclyde had the highest and the Ewald had the smallest constraint ratio. In varus displacement, the Kudo had the highest and the Ewald had the smallest peak torque and constraint ratio. The constraint ratio is a characteristic that is useful for describing elbow joint behavior and for comparing the behavior of implants with that of the human elbow. Of the unlinked implants tested, the Souter-Strathclyde and Kudo prostheses most closely approximated the behavior of the human elbow joint. Implants that resemble the human elbow in appearance do not replicate normal behavior consistently, whereas other implants that do not resemble the human elbow closely do not deviate markedly from human behavior. Thus, much basic information

  10. Technical and economic analysis of replacing artificial lighting system to induction of photoperiod effect in begonia's seedlings in greenhouse

    OpenAIRE

    David,Eduardo; Rossi,Luiz Antonio; Pagliardi,Odail

    2012-01-01

    The type of artificial light used for inducing photoperiod effect in begonia's seedlings at greenhouse has fundamental importance in the growth and development of these plants and directly reflects in the electrical energy consumption used in this production process. The objective of this research was to analyze the technical and economic feasibility of replacing the current technology of artificial lighting used by the producers (incandescent lamps), by the technology of discharge lamps with...

  11. Canine intersegmental hip joint forces and moments before and after cemented total hip replacement.

    Science.gov (United States)

    Dogan, S; Manley, P A; Vanderby, R; Kohles, S S; Hartman, L M; McBeath, A A

    1991-01-01

    Intersegmental forces and moments (i.e. resultant free body forces and moments computed at the joint centers) were studied in canine hindlimbs before and after cemented total hip replacement (THR). Five large, adult, mixed-breed dogs were selected. Their gait was recorded (while leash-walked) before surgery using high-speed cinematography and a force plate. Cemented total hip replacement was unilaterally performed on each dog. Gait was again recorded at one and four months after surgery. Segmental properties (mass, center of mass, and mass moment of inertia) of the hindlimbs were experimentally determined, and an inverse dynamics approach was used to compute intersegmental forces and moments in the sagittal plane. Significant reductions in intersegmental joint forces and moments were observed in the operated hindlimb one month after surgery, although kinematic gait parameters were unaltered. Decreases of 77.0% for vertical forces, 61.9% for craniocaudal forces, and 66.2% for extension moments were determined. Four months after surgery, the joint forces and moments had returned to their preoperative values. This experiment demonstrates that the dynamics of normal walking can be restored in a canine model by four months after THR. It also shows that kinetic (rather than kinematic) parameters are more descriptive of antalgic gait in the canine.

  12. 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 ...

  13. Computer Assisted Surgery and Current Trends in Orthopaedics Research and Total Joint Replacements

    Science.gov (United States)

    Amirouche, Farid

    2008-06-01

    Musculoskeletal research has brought about revolutionary changes in our ability to perform high precision surgery in joint replacement procedures. Recent advances in computer assisted surgery as well better materials have lead to reduced wear and greatly enhanced the quality of life of patients. The new surgical techniques to reduce the size of the incision and damage to underlying structures have been the primary advance toward this goal. These new techniques are known as MIS or Minimally Invasive Surgery. Total hip and knee Arthoplasties are at all time high reaching 1.2 million surgeries per year in the USA. Primary joint failures are usually due to osteoarthristis, rheumatoid arthritis, osteocronis and other inflammatory arthritis conditions. The methods for THR and TKA are critical to initial stability and longevity of the prostheses. This research aims at understanding the fundamental mechanics of the joint Arthoplasty and providing an insight into current challenges in patient specific fitting, fixing, and stability. Both experimental and analytical work will be presented. We will examine Cementless total hip arthroplasty success in the last 10 years and how computer assisted navigation is playing in the follow up studies. Cementless total hip arthroplasty attains permanent fixation by the ingrowth of bone into a porous coated surface. Loosening of an ingrown total hip arthroplasty occurs as a result of osteolysis of the periprosthetic bone and degradation of the bone prosthetic interface. The osteolytic process occurs as a result of polyethylene wear particles produced by the metal polyethylene articulation of the prosthesis. The total hip arthroplasty is a congruent joint and the submicron wear particles produced are phagocytized by macrophages initiating an inflammatory cascade. This cascade produces cytokines ultimately implicated in osteolysis. Resulting bone loss both on the acetabular and femoral sides eventually leads to component instability. As

  14. Experiences from the Architectural Migration of a Joint Replacement Surgery Information System

    Directory of Open Access Journals (Sweden)

    Samuli Niiranen

    2008-01-01

    Full Text Available The goal of this study is to present the experiences gathered from the migration of an existing and deployed joint replacement surgery information system from a classical 2-tier architecture to a 4-tier architecture. These include discussion on the motivation for the migration and on the technical benefits of the chosen technical migration path and an evaluation of user experiences. The results from the analysis of clinical end-user and administrator experiences show an increase in the perceived performance and maintainability of the system and a high level of acceptance for the new system version.

  15. Patient expectations of hip and knee joint replacement surgery and postoperative health status.

    Science.gov (United States)

    Cross, Marita; Lapsley, Helen; Barcenilla, Annica; Parker, David; Coolican, Myles; March, Lyn

    2009-03-01

    To explore the relationship between preoperative patient expectations and postoperative health status in patients undergoing joint replacement surgery, with particular emphasis on the types of expectations held by patients. Respondents completed the Hospital for Special Surgery (HSS) Hip/Knee Replacement Expectations Questionnaires pre-surgery, in addition to the Western Ontario and McMaster Osteoarthritis Index (WOMAC™) and the Short-Form 36-Item (SF-36) Health Survey and the Arthritis Self-Efficacy Scale. The WOMAC™ Index and SF-36 were also completed 3 and 6 months post-surgery. A total of 106 patients (total hip replacement [THR] = 28; total knee replacement [TKR] = 78) completed questionnaires. No differences were seen in overall expectations between males and females or older or younger patients, although some differences between the age groups were seen for individual expectations on the HSS expectations questionnaires. For THR, a higher rating of the importance of expectations was correlated with a lesser improvement in pain from pre-surgery to 3 months post-surgery, whereas for TKR, a higher rating of expectations was associated with a greater improvement in function to 6 months post-surgery. Patients have high expectations of surgery, which are correlated with post-surgery pain and function. Identifying the broad range of expectations may be helpful in preparation for surgery and gaining greater satisfaction with outcomes.

  16. The Biologic Response to Polyetheretherketone (PEEK) Wear Particles in Total Joint Replacement: A Systematic Review.

    Science.gov (United States)

    Stratton-Powell, Ashley A; Pasko, Kinga M; Brockett, Claire L; Tipper, Joanne L

    2016-11-01

    Polyetheretherketone (PEEK) and its composites are polymers resistant to fatigue strain, radiologically transparent, and have mechanical properties suitable for a range of orthopaedic applications. In bulk form, PEEK composites are generally accepted as biocompatible. In particulate form, however, the biologic response relevant to joint replacement devices remains unclear. The biologic response to wear particles affects the longevity of total joint arthroplasties. Particles in the phagocytozable size range of 0.1 µm to 10 µm are considered the most biologically reactive, particularly particles with a mean size of PEEK-based wear debris from total joint arthroplasties. (1) What are the quantitative characteristics of PEEK-based wear particles produced by total joint arthroplasties? (2) Do PEEK wear particles cause an adverse biologic response when compared with UHMWPE or a similar negative control biomaterial? (3) Is the biologic response affected by particle characteristics? Embase and Ovid Medline databases were searched for studies that quantified PEEK-based particle characteristics and/or investigated the biologic response to PEEK-based particles relevant to total joint arthroplasties. The keyword search included brands of PEEK (eg, MITCH, MOTIS) or variations of PEEK types and nomenclature (eg, PAEK, CFR-PEEK) in combination with types of joint (eg, hip, knee) and synonyms for wear debris or immunologic response (eg, particles, cytotoxicity). Peer-reviewed studies, published in English, investigating total joint arthroplasty devices and cytotoxic effects of PEEK particulates were included. Studies investigating devices without articulating bearings (eg, spinal instrumentation devices) and bulk material or contact cytotoxicity were excluded. Of 129 studies, 15 were selected for analysis and interpretation. No studies were found that isolated and characterized PEEK wear particles from retrieved periprosthetic human tissue samples. In the four studies that

  17. Elbow replacement

    Science.gov (United States)

    ... of the arm bones. The ends of the artificial joint are usually glued in place into each bone. They can be connected with a hinge. The ... this procedure include: Blood vessel damage during surgery Bone break during surgery Dislocation of the artificial joint Loosening of the artificial joint over time ...

  18. Patterns and Mechanisms of Artificial Kidney Failure during Continuous Renal Replacement Therapy.

    Science.gov (United States)

    Zhang, Ling; Tanaka, Aiko; Zhu, Guijun; Baldwin, Ian; Eastwood, Glenn M; Bellomo, Rinaldo

    2016-01-01

    We aimed to describe the previously unstudied relationship between circuit pressures and circuit clotting, here labeled as 'artificial kidney failure' (AKF), in patients receiving continuous renal replacement therapy (CRRT). We performed an observational study of CRRT-treated critically ill patients to continuously record the multiple CRRT circuit pressures. Three patterns of access outflow dysfunction (AOD) were also noted: severe, moderate and mild. Compared with circuits without AOD, circuits experiencing at least one AOD episode had shorter lifespans (14.2 ± 12.7 vs. 21.3 ± 16.5 h, p = 0.057). This effect was more obvious with moderate or severe AOD (8.7 ± 4.6 vs. 20.6 ± 15.7 h, p = 0.007). If any AOD events occurred within the first 4 h, the sensitivity and specificity in predicting early-immediate AKF were 53.4 and 94.4%, respectively. Early and intermediate AKF during CRRT is most likely dependent on AOD, which is a frequent event with variable severity. © 2015 S. Karger AG, Basel.

  19. Nuclear medicine and the failed joint replacement: Past, present, and future.

    Science.gov (United States)

    Palestro, Christopher J

    2014-07-28

    (SPECT)/electronic computer X-ray tomography technique (CT) and the availability of fluorine-18 fluoride PET suggests that the diagnostic paradigm may be shifting again. By providing the anatomic information lacking in conventional radionuclide studies, there is renewed interest in bone scintigraphy, performed as a SPECT/CT procedure, for detecting joint instability, mechanical loosening and component malpositioning. Fluoride-PET may provide new insights into periprosthetic bone metabolism. The objective of this manuscript is to provide a comprehensive review of the evolution of nuclear medicine imaging of joint replacements.

  20. Depression and the Overall Burden of Painful Joints: An Examination among Individuals Undergoing Hip and Knee Replacement for Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Rajiv Gandhi

    2015-01-01

    Full Text Available The majority of patients with hip or knee osteoarthritis (OA report one or more symptomatic joints apart from the one targeted for surgical care. Therefore, the purpose of the present study was to investigate the association between the burden of multiple symptomatic joints and self-reported depression in patients awaiting joint replacement for OA. Four hundred and seventy-five patients at a single centre were evaluated. Patients self-reported joints that were painful and/or symptomatic most days of the previous month on a homunculus, with nearly one-third of the sample reporting 6 or more painful joints. The prevalence of depression was 12.2% (58/475. When adjusted for age, sex, education level, hip or knee OA, body mass index, chronic condition count, and joint-specific WOMAC scores, each additional symptomatic joint was associated with a 19% increased odds (odds ratio: 1.19 (95% CI: 1.08, 1.31, P<0.01 of self-reported depression. Individuals reporting 6 or more painful joints had 2.5-fold or greater odds of depression when compared to those patients whose symptoms were limited to the surgical joint. A focus on the surgical joint alone is likely to miss a potentially important determinant of postsurgical patient-reported outcomes in patients undergoing hip or knee replacement.

  1. Knee Joint Loads and Surrounding Muscle Forces during Stair Ascent in Patients with Total Knee Replacement

    Science.gov (United States)

    Rasnick, Robert; Standifird, Tyler; Reinbolt, Jeffrey A.; Cates, Harold E.

    2016-01-01

    Total knee replacement (TKR) is commonly used to correct end-stage knee osteoarthritis. Unfortunately, difficulty with stair climbing often persists and prolongs the challenges of TKR patents. Complete understanding of loading at the knee is of great interest in order to aid patient populations, implant manufacturers, rehabilitation, and future healthcare research. Musculoskeletal modeling and simulation approximates joint loading and corresponding muscle forces during a movement. The purpose of this study was to determine if knee joint loadings following TKR are recovered to the level of healthy individuals, and determine the differences in muscle forces causing those loadings. Data from five healthy and five TKR patients were selected for musculoskeletal simulation. Variables of interest included knee joint reaction forces (JRF) and the corresponding muscle forces. A paired samples t-test was used to detect differences between groups for each variable of interest (pknee extension moment and muscle forces during the loading response phase indicates the presence of deficits in TKR in quadriceps muscle force production during stair ascent. This result combined with greater flexor muscle forces resulted in similar compressive JRF during loading response between groups. PMID:27258086

  2. Hip Joint Replacement Using Monofilament Polypropylene Surgical Mesh: An Animal Model

    Directory of Open Access Journals (Sweden)

    Jacek Białecki

    2014-01-01

    Full Text Available Hip joint dysplasia is a deformation of the articular elements (pelvic acetabulum, head of the femur, and/or ligament of the head of the femur leading to laxity of the hip components and dislocation of the femoral head from the pelvic acetabulum. Diagnosis is based on symptoms observed during clinical and radiological examinations. There are two treatment options: conservative and surgical. The classic surgical procedures are juvenile pubic symphysiodesis (JPS, triple pelvic osteotomy (TPO, total hip replacement (THR, and femoral head and neck resection (FHNE. The aim of this experiment was to present an original technique of filling the acetabulum with a polypropylene implant, resting the femoral neck directly on the mesh. The experiment was performed on eight sheep. The clinical value of the new surgical technique was evaluated using clinical, radiological, and histological methods. This technique helps decrease the loss of limb length by supporting the femoral neck on the mesh equivalent to the femoral head. It also reduces joint pain and leads to the formation of stable and mobile pseudarthrosis. The mesh manifested osteoprotective properties and enabled the formation of a stiff-elastic connection within the hip joint. The method is very cost-effective and the technique itself is simple to perform.

  3. Hip Joint Replacement Using Monofilament Polypropylene Surgical Mesh: An Animal Model

    Science.gov (United States)

    Białecki, Jacek; Klimowicz-Bodys, Małgorzata Dorota; Wierzchoś, Edward; Kołomecki, Krzysztof

    2014-01-01

    Hip joint dysplasia is a deformation of the articular elements (pelvic acetabulum, head of the femur, and/or ligament of the head of the femur) leading to laxity of the hip components and dislocation of the femoral head from the pelvic acetabulum. Diagnosis is based on symptoms observed during clinical and radiological examinations. There are two treatment options: conservative and surgical. The classic surgical procedures are juvenile pubic symphysiodesis (JPS), triple pelvic osteotomy (TPO), total hip replacement (THR), and femoral head and neck resection (FHNE). The aim of this experiment was to present an original technique of filling the acetabulum with a polypropylene implant, resting the femoral neck directly on the mesh. The experiment was performed on eight sheep. The clinical value of the new surgical technique was evaluated using clinical, radiological, and histological methods. This technique helps decrease the loss of limb length by supporting the femoral neck on the mesh equivalent to the femoral head. It also reduces joint pain and leads to the formation of stable and mobile pseudarthrosis. The mesh manifested osteoprotective properties and enabled the formation of a stiff-elastic connection within the hip joint. The method is very cost-effective and the technique itself is simple to perform. PMID:24987672

  4. 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.

  5. Estimation of fatigue life for aluminium welded joints with the application of artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Karakas, Oe.

    2011-10-15

    The aim of this investigation was determining the fatigue behaviour of welded aluminium joints and so the appertaining SN-lines by application of Artificial Neural Network (ANN) architectures. For this, fatigue data obtained with aluminium welded joints subjected to constant amplitude loading were used. The main benefit of ANN is the good description of the effects of different factors on fatigue life. The results determined by the ANN method for four aluminium alloys are displayed in scatter bands of SN-lines. It is observed that the trained results are in good agreement with the tested data and enable the estimation of SN-lines. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Effects of clinical pathways in the joint replacement: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Faggiano F

    2009-07-01

    Full Text Available Abstract Background A meta-analysis was performed to evaluate the use of clinical pathways for hip and knee joint replacements when compared with standard medical care. The impact of clinical pathways was evaluated assessing the major outcomes of in-hospital hip and knee joint replacement processes: postoperative complications, number of patients discharged at home, length of in-hospital stay and direct costs. Methods Medline, Cinahl, Embase and the Cochrane Central Register of Controlled Trials were searched. The search was performed from 1975 to 2007. Each study was assessed independently by two reviewers. The assessment of methodological quality of the included studies was based on the Jadad methodological approach and on the New Castle Ottawa Scale. Data analysis abided by the guidelines set out by The Cochrane Collaboration regarding statistical methods. Meta-analyses were performed using RevMan software, version 4.2. Results Twenty-two studies met the study inclusion criteria and were included in the meta-analysis for a total sample of 6,316 patients. The aggregate overall results showed significantly fewer patients suffering postoperative complications in the clinical pathways group when compared with the standard care group. A shorter length of stay in the clinical pathway group was also observed and lower costs during hospital stay were associated with the use of the clinical pathways. No significant differences were found in the rates of discharge to home. Conclusion The results of this meta-analysis show that clinical pathways can significantly improve the quality of care even if it is not possible to conclude that the implementation of clinical pathways is a cost-effective process, because none of the included studies analysed the cost of the development and implementation of the pathways. Based on the results we assume that pathways have impact on the organisation of care if the care process is structured in a standardised way

  7. Cervical Footprint Anthropometry in Indian Population: Implications on Design of Artificial Disc Replacement Devices.

    Science.gov (United States)

    Kulkarni, Arvind Gopalrao; Patil, Vishwanath Mahabaleshwar; Bangalore, Shashidhar Kantharajanna; Saraf, Abhishek

    2016-02-01

    Cross-sectional study. To accurately measure the dimensions of cervical endplates based on computed tomography (CT) scans in Indian population and assess accuracy of match with currently available cervical disc prostheses. The dimensions of currently available cervical disc replacement implants are based on early published geometrical measurements of vertebrae endplates for Caucasian population. To author's knowledge, similar study has not been published for patients from Indian subcontinent. CT scans of cervical spine of patients from Indian subcontinent were collected and reviewed. Seventy patients (54 men and 16 women; aged 18-56 years with average of 37 years) who underwent CT scans of cervical spine were included in study. 3D CT scans of sub axial cervical spine (C3 to C7) were analyzed. The anterior-posterior (AP) and central mediolateral (CML) dimensions of superior and inferior endplates from C3 to C7 were measured using digital measuring system. A total of 560 endplates of 70 patients were included in the study. The AP diameter of cervical endplates ranged from 0.87 to 2.47 cm. The CML diameters ranged from 0.84 to 2.98 cm. For levels C3/C4 and C4/C5 for AP dimension Prestige-LP (90.5%) and Prodisc-C (89%) discs showed higher percentage of matching than Discover discs (58.5%). For CML diameter, Prestige-LP (69.5%), Prodisc-C (70%) and Discover (39.5%) discs showed almost similar matching with measured endplates. For levels C5/C6 and C6/C7 for AP dimension, Prestige-LP (67.25%), Prodisc-C (49.35%) and Discover (51.5%) discs showed similar matching. For CML diameter Prestige-LP (32%), Prodisc-C (27.5%) and Discover (42.2%) discs showed poor matching with measured endplates. This study indicates need for redesign of cervical disc prostheses to match Indian patients. The collected anthropometric dimensions from this study may be used to design and develop indigenous artificial total disc replacement prosthesis and even cervical cages in India. With the present

  8. Arthritic periosteal tissue from joint replacement surgery: a novel, autologous source of stem cells.

    Science.gov (United States)

    Chang, Hana; Docheva, Denitsa; Knothe, Ulf R; Knothe Tate, Melissa L

    2014-03-01

    The overarching aim of this study is to assess the feasibility of using periosteal tissue from the femoral neck of arthritic hip joints, usually discarded in the normal course of hip replacement surgery, as an autologous source of stem cells. In addition, the study aims to characterize intrinsic differences between periosteum-derived cell (PDC) populations, isolated via either enzymatic digestion or a migration assay, including their proliferative capacity, surface marker expression, and multipotency, relative to commercially available human bone marrow-derived stromal cells (BMSCs) cultured under identical conditions. Commercial BMSCs and PDCs were characterized in vitro, using a growth assay, flow cytometry, as well as assay of Oil Red O, alizarin red, and Safranin O/Fast Green staining after respective culture in adipo-, osteo-, and chondrogenic media. Based on these outcome measures, PDCs exhibited proliferation rate, morphology, surface receptor expression, and multipotency similar to those of BMSCs. No significant correlation was observed between outcome measures and donor age or diagnosis (osteoarthritis [OA] and rheumatoid arthritis [RA], respectively), a profound finding given recent rheumatological studies indicating that OA and RA share not only common biomarkers and molecular mechanisms but also common pathophysiology, ultimately resulting in the need for joint replacement. Furthermore, PDCs isolated via enzymatic digestion and migration assay showed subtle differences in surface marker expression but otherwise no significant differences in proliferation or multipotency; the observed differences in surface marker expression may indicate potential effects of isolation method on the population of cells isolated and/or the behavior of the respective isolated cell populations. This study demonstrates, for the first time to our knowledge, the feasibility of using arthritic tissue resected during hip replacement as a source of autologous stem cells. In sum

  9. Let native species take their course: Ambrosia artemisiifolia replacement during natural or ;artificial; succession

    Science.gov (United States)

    Gentili, Rodolfo; Montagnani, Chiara; Gilardelli, Federica; Guarino, Maria Francesca; Citterio, Sandra

    2017-07-01

    Ambrosia artemisiifolia is able to dominate the early stages of vegetation succession in open/disturbed habitats, spreading out into available empty niches, after which it can be progressively replaced by perennial plants. In this study, we considered the time-span in which the species is suppressed during active (restoration actions) and passive (spontaneous) vegetation recovery. In particular, we envisaged that A. artemisiifolia growth and fitness may be strongly reduced and that the species may rapidly be suppressed within a short time during succession as a consequence of the increase of vegetation cover, both natural or artificially induced, in a disturbed area of northern Italy. Three different treatments were applied within an abandoned quarry area commonly invaded by A. artemisiifolia: (i) spontaneous succession i.e. (control), (ii) hayseed and (iii) a commercial seed mixture. We determined the effect of mixtures of grassland species, established from native hayseed or from a commercial seed mixture, on A. artemisiifolia growth and fitness traits over time in comparison to a non-seeded area left to spontaneous succession. The results demonstrated that, after the first growing season, compared with spontaneous succession, both commercial seed and hayseed resulted in a strong reduction of A. artemisiifolia abundance and growth rate, in terms of both vegetative and reproductive traits. After the second growing season, A. artemisiifolia was completely suppressed in the commercial seed treatment, and after the third growing season it was also suppressed in the spontaneous succession and hayseed treatments. This study indicated that both active and passive vegetation recovery (by niche filling and competitive exclusion) could be used as methods individually or in combination with other methods, such as mowing and biological control, to suppress A. artemisiifolia from anthropogenic habitats.

  10. Prosthesis infections after orthopedic joint replacement: the possible role of bacterial biofilms

    Directory of Open Access Journals (Sweden)

    Zhijun Song

    2013-06-01

    Full Text Available 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, important to understand the comprehensive interaction between the microbiological situation and the host immune responses that lead to prosthesis infections. Evidence indicates that prosthesis infections are actually biofilm-correlated infections that are highly resistant to antibiotic treatment and the host immune responses. The authors reviewed the related literature in the context of their clinical experience, and discussed the possible etiology and mechanism leading to the infections, especially problems related to bacterial biofilm, and prophylaxis and treatment of infection, including both microbiological and surgical measures. Recent progress in research into bacterial biofilm and possible future treatment options of prosthesis-related infections are discussed.

  11. Experimental and thermodynamic assessment of beryllium-replacement materials for CANDU brazed joints

    International Nuclear Information System (INIS)

    Potter, K.N.; Ferrier, G.A.; Corcoran, E.C.; Dimayuga, F.C.

    2015-01-01

    Currently, appendages are joined to CANDU fuel elements via a brazing process, with beryllium as the filler material. A potential reduction in the occupational limit on airborne beryllium particulates has motivated research into alternative brazing materials. To this end, the Canadian nuclear industry has funded an initiative to identify and evaluate the suitability of several candidate brazing materials. This work describes contributions toward the assessment of alternative brazing materials from the Royal Military College of Canada (RMCC). An impact testing method was developed to evaluate the mechanical strength of candidate braze joints.Thermodynamic modelling was performed to predict the aqueous behaviour of each candidate material in CANDU coolant conditions characteristic of reactor shutdown, and corrosion experiments are underway to support modelling predictions.The results of these activities will assist in selecting a suitable replacement material for beryllium. (author)

  12. Experimental and thermodynamic assessment of beryllium-replacement materials for CANDU brazed joints

    Energy Technology Data Exchange (ETDEWEB)

    Potter, K.N.; Ferrier, G.A.; Corcoran, E.C., E-mail: Kieran.Potter@rmc.ca [Royal Military College of Canada, Kingston ON, (Canada); Dimayuga, F.C. [Canadian Nuclear Laboratories, Chalk River, ON (Canada)

    2015-07-01

    Currently, appendages are joined to CANDU fuel elements via a brazing process, with beryllium as the filler material. A potential reduction in the occupational limit on airborne beryllium particulates has motivated research into alternative brazing materials. To this end, the Canadian nuclear industry has funded an initiative to identify and evaluate the suitability of several candidate brazing materials. This work describes contributions toward the assessment of alternative brazing materials from the Royal Military College of Canada (RMCC). An impact testing method was developed to evaluate the mechanical strength of candidate braze joints.Thermodynamic modelling was performed to predict the aqueous behaviour of each candidate material in CANDU coolant conditions characteristic of reactor shutdown, and corrosion experiments are underway to support modelling predictions.The results of these activities will assist in selecting a suitable replacement material for beryllium. (author)

  13. Is there a risk of permanent renal dysfunction after primary total hip and knee joint replacements?

    DEFF Research Database (Denmark)

    Hassan, Basim Kamil; Dessau, Ram Benny; Sahlström, Arne

    2016-01-01

    creatinine was an indicative of postoperative renal injury. The highest serum creatinine during the first postoperative week was chosen as a sign for maximum acute renal injury and was compared to the highest serum creatinine during the following 4-12 months. RESULTS: One hundred and forty two patients...... with an increase in postoperative serum creatinine were included in the follow-up study. Six patients (4.2 %) died due to non-renal causes during the follow-up period. One patient died of severe renal injury, which was relatively very early postoperatively, and another patient had a rise in serum creatinine to 316...... μmol/l during the follow-up period. All the remaining 132 patients (94 %) had full recovery with serum creatinine which returned to preoperative levels. CONCLUSIONS: This study did not confirm that patients who underwent primary total hip and knee joint replacement surgery were at risk of developing...

  14. Biotribological properties of UHMWPE grafted with AA under lubrication as artificial joint.

    Science.gov (United States)

    Deng, Yaling; Xiong, Dangsheng; Wang, Kun

    2013-09-01

    Osteolysis caused by wear particles from polyethylene in the artificial hip joints is a serious issue. In order to endow the low friction and wear of the bearing surface of ultra-high molecular weight polyethylene (UHMWPE) artificial joint for a longer term, hydrophilic acrylic acid (AA) was grafted on UHMWPE powders with the method of ultraviolet irradiation and then the modified powders were hot pressed. The tribological properties of modified UHMWPE sliding against CoCrMo metallic plate on reciprocating tribometer under calf serum, saline and distilled water lubrication during a long-term friction were investigated. The measurement of Fourier-transform infrared spectroscopy indicates that AA is successfully grafted on the surface of UHMWPE powders by photo-induced graft polymerization. Contact angles of UHMWPE are decreased from 83° to 35° by grafting and the surface wettability is effectively improved. The tensile strength of modified sample decreases. The friction coefficient and wear rate of UHMWPE-g-PAA under calf serum, saline and distilled water lubrication are lower than that of untreated UHMWPE. With the increase of grafting ratio, the wear rate of UHMWPE-g-PAA decreases firstly and then increases. The modified UHMWPE with grafting ratio of 3.5 % has the lowest wear rate, which is just quarter of the untreated UHMWPE. The hydrated PAA polymer brushes enclosed in the UHMWPE bulk material provide continuous lubrication during long term sliding.

  15. The mechanical and tribological properties of UHMWPE loaded ALN after mechanical activation for joint replacements.

    Science.gov (United States)

    Gong, Kemeng; Qu, Shuxin; Liu, Yumei; Wang, Jing; Zhang, Yongchao; Jiang, Chongxi; Shen, Ru

    2016-08-01

    Ultra-high molecular weight polyethylene (UHMWPE) loaded with alendronate sodium (ALN) has tremendous potential as an orthopeadic biomaterial for joint replacements. However, poor mechanical and tribological properties of UHMWPE-ALN are still obstacle for further application. The purpose of this study was to investigate the effect and mechanism of mechanical activation on mechanical and tribological properties of 1wt% ALN-loaded UHMWPE (UHMWPE-ALN-ma). In this study, tensile test, small punch test and reciprocating sliding wear test were applied to characterize the mechanical and tribological properties of UHMWPE-ALN-ma. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR) were employed to characterize UHMWPE-ALN-ma. Tensile test and small punch test showed that Young׳s modulus, tensile strength and work-to-failure (WTF) of UHMWPE-ALN-ma increased significantly compared to those of UHMWPE-ALN. The friction coefficients and wear factors of UHMWPE-ALN-ma both decreased significantly compared to those of UHMWPE-ALN. Mechanical activation obviously reduced type 1 (void) and type 2 (the disconnected and dislocated machining marks) fusion defects of UHMWPE-ALN-ma, which were revealed by SEM images of freeze fracture surfaces after etching and lateral surfaces of specimens after extension to fracture, respectively. It was attributed to peeled-off layers and chain scission of molecular chains of UHMWPE particles after mechanical activation, which were revealed by SEM images and FTIR spectra of UHMWPE-ALN-ma and UHMWPE-ALN, respectively. Moreover, EDS spectra revealed the more homogeneous distribution of ALN in UHMWPE-ALN-ma compared to that of UHMWPE-ALN. The present results showed that mechanical activation was a potential strategy to improve mechanical and tribological properties of UHMWPE-ALN-ma as an orthopeadic biomaterial for joint replacements. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Decision Support for Joint Replacement: Implications for Decisional Conflict and Willingness to Undergo Surgery.

    Science.gov (United States)

    Riffin, Catherine; Pillemer, Karl; Reid, M Cary; Tung, Judy; L Ckenhoff, Corinna E

    2018-03-02

    The present study investigates age differences in the types of decision support that total joint replacement (TJR) candidates desire and receive when making the decision to pursue surgery. We consider the social structural (relationship to the patient) and experiential factors (network members' experience with TJR) that influence individuals' support preferences and the interactions of these factors with age. We also examine whether a lack of support is linked with increased decisional conflict and reduced willingness to undergo surgery. A telephone survey was conducted with 100 individuals (aged 40+) who were contemplating knee or hip replacement. TJR candidates desired and received decision support from health care providers, family members, and individuals who had previously undergone TJR. They reported higher deficits in informational and emotional support than in instrumental support. Overall, a lack of instrumental support was associated with greater decisional conflict; a lack of instrumental support and a lack of informational support were associated with reduced willingness to undergo TJR. Our findings point to the importance of involving both formal and informal network members in TJR discussions, and the need for informational guidance and practical assistance to reduce decisional conflict and uncertainty among individuals considering TJR.

  17. Architectural design of diamond-like carbon coatings for long-lasting joint replacements.

    Science.gov (United States)

    Liu, Yujing; Zhao, Xiaoli; Zhang, Lai-Chang; Habibi, Daryoush; Xie, Zonghan

    2013-07-01

    Surface engineering through the application of super-hard, low-friction coatings as a potential approach for increasing the durability of metal-on-metal replacements is attracting significant attention. In this study innovative design strategies are proposed for the development of diamond-like-carbon (DLC) coatings against the damage caused by wear particles on the joint replacements. Finite element modeling is used to analyze stress distributions induced by wear particles of different sizes in the newly-designed coating in comparison to its conventional monolithic counterpart. The critical roles of architectural design in regulating stress concentrations and suppressing crack initiation within the coatings is elucidated. Notably, the introduction of multilayer structure with graded modulus is effective in modifying the stress field and reducing the magnitude and size of stress concentrations in the DLC diamond-like-carbon coatings. The new design is expected to greatly improve the load-carrying ability of surface coatings on prosthetic implants, in addition to the provision of damage tolerance through crack arrest. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Pneumatic Artificial Muscles Force Modelling and the Position and Stiffness Control on the Knee Joint of the Musculoskeletal Leg

    OpenAIRE

    Jingtao Lei; Jianmin Zhu

    2017-01-01

    Pneumatic artificial muscles (PAMs) have properties similar to biological muscle and are widely used in robotics as actuators. A musculoskeletal leg mechanism driven by PAMs is presented in this paper. The joint stiffness of the musculoskeletal bionic leg for jumping movement needs to be analysed. The synchronous control on the position and stiffness of the joint is important to improve the flexibility of leg. The accurate force model of PAM is the foundation to achieving better control and d...

  19. Mechanical characterization of PVA hydrogel to be used as artificial joint cartilage reinforced by irradiation techniques

    International Nuclear Information System (INIS)

    Bavaresco, Vanessa Petrilli; Zavaglia, Cecilia A.C.; Reis, Marcelo de Carvalho

    2002-01-01

    Crosslinked networks of polyvinyl alcohol (PVA) produced from PVA aqueous solution and induced by radiation has been recently developed, and their mechanical properties have been studied. These materials are too fragile to be useful for artificial joint cartilage applications, unless reinforced in some way. In this work, the mechanical resistance of PVA hydrogel produced by irradiation techniques was studied. Polyvinyl alcohol films from 15 and 20% w/w aqueous solutions were acetalized by immersing it in an acetalization bath containing aqueous formaldehyde, sulfuric acid and sodium sulfate anhydrous (60:50:300 g) at 60 deg C. The acetalized samples were irradiated (Dynamitron (E = 1,5 MeV)) with 25, 50, 75, 100 kGy doses. Hydrogel samples were characterized by indentation creep test and water swelling. The results obtained in this study suggest the improving of the mechanical properties of the hydrogel by the combination of acetalization and electron beam irradiation, without decreasing in the swelling properties. (author)

  20. Therapeutic validity and effectiveness of preoperative exercise on functional recovery after joint replacement: a systematic review and meta-analysis.

    NARCIS (Netherlands)

    Hoogeboom, T.J.; Oosting, E.; Vriezekolk, J.E.; Veenhof, C.; Siemonsma, P.C.; Bie, R.A. de; Ende, C.H.M. van den; Meeteren, N.L.U. van

    2012-01-01

    Background: Our aim was to develop a rating scale to assess the therapeutic validity of therapeutic exercise programmes. By use of this rating scale we investigated the therapeutic validity of therapeutic exercise in patients awaiting primary total joint replacement (TJR). Finally, we studied the

  1. Comparison of one-step and sequentially irradiated ultrahigh-molecular-weight polyethylene for total joint replacements

    Czech Academy of Sciences Publication Activity Database

    Šlouf, Miroslav; Kotek, Jiří; Baldrian, Josef; Kovářová, Jana; Fencl, J.; Bouda, T.; Janigová, I.

    101B, č. 3 (2013), s. 414-422 ISSN 1552-4973 R&D Projects: GA TA ČR TA01011406; GA MZd NT12229 Institutional research plan: CEZ:AV0Z40500505 Keywords : polyethylene (UHMWPE) * joint replacement * mechanical properties Subject RIV: FI - Traumatology, Orthopedics Impact factor: 2.328, year: 2013

  2. Ultra Low-Dose Naloxone and Tramadol/Acetaminophen in Elderly Patients Undergoing Joint Replacement Surgery: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Ngozi N Imasogie

    2009-01-01

    Full Text Available OBJECTIVE: A pilot study was conducted to assess whether both the rationale and feasibility exist for future randomized clinical trials to evaluate the combined use of naloxone infusion and tramadol/acetaminophen as opioid-sparing drugs in elderly patients undergoing lower extremity joint replacement surgery.

  3. Impact of the economic downturn on total joint replacement demand in the United States: updated projections to 2021.

    Science.gov (United States)

    Kurtz, Steven M; Ong, Kevin L; Lau, Edmund; Bozic, Kevin J

    2014-04-16

    Few studies have explored the role of the National Health Expenditure and macroeconomics on the utilization of total joint replacement. The economic downturn has raised questions about the sustainability of growth for total joint replacement in the future. Previous projections of total joint replacement demand in the United States were based on data up to 2003 using a statistical methodology that neglected macroeconomic factors, such as the National Health Expenditure. Data from the Nationwide Inpatient Sample (1993 to 2010) were used with United States Census and National Health Expenditure data to quantify historical trends in total joint replacement rates, including the two economic downturns in the 2000s. Primary and revision hip and knee arthroplasty were identified using codes from the International Classification of Diseases, Ninth Revision, Clinical Modification. Projections in total joint replacement were estimated using a regression model incorporating the growth in population and rate of arthroplasties from 1993 to 2010 as a function of age, sex, race, and census region using the National Health Expenditure as the independent variable. The regression model was used in conjunction with government projections of National Health Expenditure from 2011 to 2021 to estimate future arthroplasty rates in subpopulations of the United States and to derive national estimates. The growth trend for the incidence of joint arthroplasty, for the overall United States population as well as for the United States workforce, was insensitive to economic downturns. From 2009 to 2010, the total number of procedures increased by 6.0% for primary total hip arthroplasty, 6.1% for primary total knee arthroplasty, 10.8% for revision total hip arthroplasty, and 13.5% for revision total knee arthroplasty. The National Health Expenditure model projections for primary hip replacement in 2020 were higher than a previously projected model, whereas the current model estimates for total

  4. Replacement

    Directory of Open Access Journals (Sweden)

    S. Radhakrishnan

    2014-03-01

    Full Text Available The fishmeal replaced with Spirulina platensis, Chlorella vulgaris and Azolla pinnata and the formulated diet fed to Macrobrachium rosenbergii postlarvae to assess the enhancement ability of non-enzymatic antioxidants (vitamin C and E, enzymatic antioxidants (superoxide dismutase (SOD and catalase (CAT and lipid peroxidation (LPx were analysed. In the present study, the S. platensis, C. vulgaris and A. pinnata inclusion diet fed groups had significant (P < 0.05 improvement in the levels of vitamins C and E in the hepatopancreas and muscle tissue. Among all the diets, the replacement materials in 50% incorporated feed fed groups showed better performance when compared with the control group in non-enzymatic antioxidant activity. The 50% fishmeal replacement (best performance diet fed groups taken for enzymatic antioxidant study, in SOD, CAT and LPx showed no significant increases when compared with the control group. Hence, the present results revealed that the formulated feed enhanced the vitamins C and E, the result of decreased level of enzymatic antioxidants (SOD, CAT and LPx revealed that these feeds are non-toxic and do not produce any stress to postlarvae. These ingredients can be used as an alternative protein source for sustainable Macrobrachium culture.

  5. SHORT- AND MIDDLE-TERM RESULTS OF KNEE JOINT REPLACEMENT WITH ZIMMER NexGen CR AND LPS IMPLANTS

    Directory of Open Access Journals (Sweden)

    A. B. Slobodskoy

    2011-01-01

    Full Text Available The article presents the experience gained by orthopedic unit of Saratov Regional Clinical Hospital at knee joint replacement with modern implants. We analyzed use of Zimmer NexGen CR and LPC implants for initial total knee joint replacement in 285 patients. The monitoring continued for 5 years. Good and excellent results were observed in 92% of cases. Pyogenic complications were observed in 2.3% of cases. The article describes the methods of surgical intervention and post-surgical rehabilitation. We consider our experience with Zimmer NexGen LPS and CR knee-joint implants as positive and prospective for further use.

  6. Postoperative cognitive dysfunction and its relationship to cognitive reserve in elderly total joint replacement patients.

    Science.gov (United States)

    Scott, J E; Mathias, J L; Kneebone, A C; Krishnan, J

    2017-06-01

    Whether total joint replacement (TJR) patients are susceptible to postoperative cognitive dysfunction (POCD) remains unclear due to inconsistencies in research methodologies. Moreover, cognitive reserve may moderate the development of POCD after TJR, but has not been investigated in this context. The current study investigated POCD after TJR, and its relationship with cognitive reserve, using a more rigorous methodology than has previously been utilized. Fifty-three older adults (aged 50+) scheduled for TJR were assessed pre and post surgery (6 months). Forty-five healthy controls matched for age, gender, and premorbid IQ were re-assessed after an equivalent interval. Cognition, cognitive reserve, and physical and mental health were all measured. Standardized regression-based methods were used to assess cognitive changes, while controlling for the confounding effect of repeated cognitive testing. TJR patients only demonstrated a significant decline in Trail Making Test Part B (TMT B) performance, compared to controls. Cognitive reserve only predicted change in TMT B scores among a subset of TJR patients. Specifically, patients who showed the most improvement pre to post surgery had significantly higher reserve than those who showed the greatest decline. The current study provides limited evidence of POCD after TJR when examined using a rigorous methodology, which controlled for practice effects. Cognitive reserve only predicted performance within a subset of the TJR sample. However, the role of reserve in more cognitively compromised patients remains to be determined.

  7. Metal hypersensitivity testing in patients undergoing joint replacement: a systematic review.

    Science.gov (United States)

    Granchi, D; Cenni, E; Giunti, A; Baldini, N

    2012-08-01

    We report a systematic review and meta-analysis of the peer-reviewed literature focusing on metal sensitivity testing in patients undergoing total joint replacement (TJR). Our purpose was to assess the risk of developing metal hypersensitivity post-operatively and its relationship with outcome and to investigate the advantages of performing hypersensitivity testing. We undertook a comprehensive search of the citations quoted in PubMed and EMBASE: 22 articles (comprising 3634 patients) met the inclusion criteria. The frequency of positive tests increased after TJR, especially in patients with implant failure or a metal-on-metal coupling. The probability of developing a metal allergy was higher post-operatively (odds ratio (OR) 1.52 (95% confidence interval (CI) 1.06 to 2.31)), and the risk was further increased when failed implants were compared with stable TJRs (OR 2.76 (95% CI 1.14 to 6.70)). Hypersensitivity testing was not able to discriminate between stable and failed TJRs, as its predictive value was not statistically proven. However, it is generally thought that hypersensitivity testing should be performed in patients with a history of metal allergy and in failed TJRs, especially with metal-on-metal implants and when the cause of the loosening is doubtful.

  8. Joint Replacement Volume Positively Correlates With Improved Hospital Performance on Centers for Medicare and Medicaid Services Quality Metrics.

    Science.gov (United States)

    Sibley, Rachel A; Charubhumi, Vanessa; Hutzler, Lorraine H; Paoli, Albit R; Bosco, Joseph A

    2017-05-01

    The Center for Medicare and Medicaid Services (CMS) is transitioning Medicare from a fee-for-service program into a value-based pay-for-performance program. In order to accomplish this goal, CMS initiated 3 programs that attempt to define quality and seek to reward high-performing hospitals and penalize poor-performing hospitals. These programs include (1) penalties for hospital-acquired conditions (HACs), (2) penalties for excess readmissions for certain conditions, and (3) performance on value-based purchasing (VBP). The objective of this study was to determine whether high-volume total joint hospitals perform better in these programs than their lower-volume counterparts. We analyzed data from the New York Statewide Planning and Research Cooperative System database on total New York State hospital discharges from 2013 to 2015 for total knee and total hip arthroplasty. This was compared to data from Hospital Compare on HAC's, excess readmissions, and VBP. From these databases, we identified 123 hospitals in New York, which participated in all 3 Medicare pay-for-performance programs and performed total joint replacements. Over the 3-year period spanning 2013-2015, hospitals in New York State performed an average of 1136.59 total joint replacement surgeries and achieved a mean readmission penalty of 0.005909. The correlation coefficient between surgery volume and combined performance score was 0.277. Of these correlations, surgery volume and VBP performance, and surgery volume and combined performance showed statistical significance (P quality, as well as joint replacement volumes and VBP performance, specifically. These findings are consistent with previously reported associations between patient outcomes and procedure volumes. However, a relationship between joint replacement volume and HAC scores or readmission penalties could not be demonstrated. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. A comprehensive joint replacement program for total knee arthroplasty: a descriptive study

    Directory of Open Access Journals (Sweden)

    Prefontaine Paul

    2008-11-01

    Full Text Available Abstract Background Total knee arthroplasty (TKA is a commonly performed surgical procedure in the US. It is important to have a comprehensive inpatient TKA program which maximizes outcomes while minimizing adverse events. The purpose of this study was to describe a TKA program – the Joint Replacement Program (JRP – and report post-surgical outcomes. Methods 74 candidates for a primary TKA were enrolled in the JRP. The JRP was designed to minimize complications and optimize patient-centered outcomes using a team approach including the patient, patient's family, and a multidisciplinary team of health professionals. The JRP consisted of a pre-operative class, standard pathways for medical care, comprehensive peri-operative pain management, aggressive physical therapy (PT, and proactive discharge planning. Measures included functional tests, knee range of motion (ROM, and medical record abstraction of patient demographics, length of stay, discharge disposition, and complications over a 6-month follow-up period. Results All patients achieved medical criteria for hospital discharge. The patients achieved the knee flexion ROM goal of 90° (91.7 ± 5.4°, but did not achieve the knee extension ROM goal of 0° (2.4 ± 2.6°. The length of hospital stay was two days for 53% of the patients, with 39% and 7% discharged in three and four days, respectively. All but three patients were discharged home with functional independence. 68% of these received outpatient physical therapy compared with 32% who received home physical therapy immediately after discharge. Two patients ( Conclusion The comprehensive JRP for TKA was associated with satisfactory clinical outcomes, short lengths of stay, a high percentage of patients discharged home with outpatient PT, and minimal complications. This JRP may represent an efficient, effective and safe protocol for providing care after a TKA.

  10. Laser textured Co-Cr-Mo alloy stored chitosan/poly(ethylene glycol) composite applied on artificial joints lubrication.

    Science.gov (United States)

    Lu, Hailin; Ren, Shanshan; Guo, Junde; Li, Yue; Li, Jianhui; Dong, Guangneng

    2017-09-01

    Arthroplasty brings the wear problems because of body fluid has poor performance as lubricant. Lubricant which is used in artificial joints will rapidly degrade and be absorbed by human body after injecting. To prolong the lubricant's effectiveness, this study prepared chitosan/poly(ethylene glycol) (CS/PEG) and textures to play a role in joint lubrication and wear protection. Chitosan (CS) and poly(ethylene glycol) which have biocompatibility and biodegradability properties can be used in human body. The tribological results shown that CS/PEG sol has excellent performance when this sol was composed by 2wt% CS and 30wt% PEG, the average friction coefficient below 0.016 under the condition of 30-90N load (pressure 4.2-12.6MPa). In this study, CS/PEG was added in the texture of artificial joints, then the surfaces of the CS/PEG formed gel via NaOH solidification effect. The CS/PEG gel film could prevent the CS/PEG sol from diluting in body fluid. Meanwhile, FT-IR, XRD, UV/vis and Raman spectra revealed that CS associated with PEG via hydrogen bond effect may form a particular structure, which leaded the good tribological performance. This study provides a new, simple and green approach to enhance tribological performances of artificial joints. Copyright © 2017. Published by Elsevier B.V.

  11. Length of stay in hospital and all-cause readmission following elective total joint replacement in elderly men

    Directory of Open Access Journals (Sweden)

    Mnatzaganian G

    2012-05-01

    Full Text Available George Mnatzaganian,1 Philip Ryan,1,2 Paul E Norman,3 David C Davidson,4 Janet E Hiller1,51School of Population Health and Clinical Practice, Discipline of Public Health, 2Data Management and Analysis Centre, The University of Adelaide, South Australia; 3School of Surgery, University of Western Australia, Western Australia; 4Royal Adelaide Hospital, South Australia; 5Faculty of Health Sciences, Australian Catholic University, Fitzroy, Victoria, AustraliaBackground: We retrospectively assessed the independent effects of patient and clinical factors on length of stay and all-cause 90-day, one-year, and two-year readmission following elective total joint replacement. We also evaluated the independent association between length of stay and readmission with postoperative five-year mortality.Methods: Longitudinal data from 819 men who had had total joint replacement were integrated with validated hospital morbidity data and mortality records. Length of stay, readmission, and mortality following total joint replacement were each modeled using multivariable proportional hazards regression.Results: Mean age at surgery was 76.3 ± 4.3 years. Median length of stay following total joint replacement decreased by 25% from 12 days in 1997–1998 to nine days in 2005–2007. Age, inhospital complications, total knee replacement, private hospital, and increased body weight were significantly associated with longer stay. A dose-response relationship between weight and length of stay was observed (P = 0.003. Crude 90-day, one-year, and two-year readmission rates were 17.3%, 47.4%, and 65.0%, respectively. Ninety-day readmission was associated with comorbidity, inhospital complications, and treatment in public hospitals. Age, comorbidity, socioeconomic disadvantage, and increased weight significantly increased the risk of one-year and two-year readmission. Patients with a body mass index ≥ 30 kg/m2 were 34% more likely to be readmitted within two years compared

  12. Patient Use of Cost and Quality Data When Choosing a Joint Replacement Provider in the Context of Reference Pricing

    Directory of Open Access Journals (Sweden)

    Ryan Kandrack

    2015-07-01

    Full Text Available Health plans are encouraging consumerism among joint replacement patients by reporting information on hospital costs and quality. Little is known about how the proliferation of such initiatives impacts patients’ selection of a surgeon and hospital. We performed a qualitative analysis of semistructured interviews with 13 patients who recently received a hip or knee replacement surgery. Patients focused on the choice of a surgeon as opposed to a hospital, and the surgeon choice was primarily made based on reputation. Most patients had long-standing relationships with an orthopedic surgeon and tended to stay with that surgeon for their replacement. Despite growing availability of cost and quality information, patients almost never used such information to make a decision.

  13. Patient Use of Cost and Quality Data When Choosing a Joint Replacement Provider in the Context of Reference Pricing

    Science.gov (United States)

    Mehrotra, Ateev; DeVries, Andrea; Wu, Sze-jung; SooHoo, Nelson F.; Martsolf, Grant R.

    2015-01-01

    Health plans are encouraging consumerism among joint replacement patients by reporting information on hospital costs and quality. Little is known about how the proliferation of such initiatives impacts patients’ selection of a surgeon and hospital. We performed a qualitative analysis of semistructured interviews with 13 patients who recently received a hip or knee replacement surgery. Patients focused on the choice of a surgeon as opposed to a hospital, and the surgeon choice was primarily made based on reputation. Most patients had long-standing relationships with an orthopedic surgeon and tended to stay with that surgeon for their replacement. Despite growing availability of cost and quality information, patients almost never used such information to make a decision. PMID:28462261

  14. Investigation on artificial blood or substitute blood replace the natural blood.

    Science.gov (United States)

    Keyhanian, Sh; Ebrahimifard, M; Zandi, M

    2014-01-01

    Blood is a liquid tissue in which dissolved with abundant chemical factors and millions of different cells The reduction of unwanted side effects, especially diseases that emerge through blood such as HIV and hepatitis, has a significant role for modern medicine of transfusion and transplantation. The issues and costs of human blood collection and storage, direct this procedure towards the use of alternatives blood. Two important research fields of this area were oxygen carriers based on hemoglobin and perfluoro chemicals. While they do not have the same quality as the blood cell products, the oxygen carrier solutions have potential clinical and non-clinical applications. The result showed that these products can reach to the body tissues easier than normal red blood cells, and can control the oxygen directly. The final aim of transfusion is to establish a transfusion system with no side effects, and the fact that oxygen carrier artificial blood has this property. The article attempts to step towards solving some problems of blood transfusion through describing the properties of artificial blood alternatives.

  15. Spontaneous resolution of posterior ankle joint loose bodies after total ankle replacement: A case report.

    Science.gov (United States)

    Lee, Raymond P; Cheng, Sally H S

    2017-06-01

    Late stage ankle osteoarthritis often presents with debilitating pain. It is common to find osteophytes and loose body formation around the joint. Total ankle arthroplasty can preserve joint mobility and pain relieve for such patient. However, when trying to remove the osteophytes and loose bodies at the posterior ankle joint, there is risk of damaging posterior structures such as the neurovascular bundle during the procedure. We are presenting a case where the posterior loose bodies remained untouched during the operation, and patient showed spontaneous resolution of the lesions with time. Patient enjoyed good function outcome after the surgery. Copyright © 2016 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  16. Effectiveness of digital subtraction radiography in detecting artificially created osteophytes and erosions in the temporomandibular joint

    Energy Technology Data Exchange (ETDEWEB)

    Kocasarac, Husniye Demirturk [Dept. of Comprehensive Dentistry, The University of Texas Health Science Center, San Antonio (United States); Celenk, Peruze [Dept. of Oral and Maxillofacial Radiology, Faculty of Dentistry, Ondokuz Mayis University, Samsun (Turkmenistan)

    2017-06-15

    Erosions and osteophytes are radiographic characteristics that are found in different stages of temporomandibular joint (TMJ) osteoarthritis. This study assessed the effectiveness of digital subtraction radiography (DSR) in diagnosing simulated osteophytes and erosions in the TMJ. Five intact, dry human skulls were used to assess the effectiveness of DSR in detecting osteophytes. Four cortical bone chips of varying thicknesses (0.5 mm, 1.0 mm, 1.5 mm, and 2.0 mm) were placed at the medial, central, and lateral aspects of the condyle anterior surface. Two defects of varying depth (1.0 mm and 1.5 mm) were created on the lateral, central, and medial poles of the condyles of 2 skulls to simulate erosions. Panoramic images of the condyles were acquired before and after artificially creating the changes. Digital subtraction was performed with Emago dental image archiving software. Five observers familiar with the interpretation of TMJ radiographs evaluated the images. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic accuracy of the imaging methods. The area under the ROC curve (Az) value for the overall diagnostic accuracy of DSR in detecting osteophytic changes was 0.931. The Az value for the overall diagnostic accuracy of panoramic imaging was 0.695. The accuracy of DSR in detecting erosive changes was 0.854 and 0.696 for panoramic imaging. DSR was remarkably more accurate than panoramic imaging in detecting simulated osteophytic and erosive changes. The accuracy of panoramic imaging in detecting degenerative changes was significantly lower than the accuracy of DSR (P<.05). DSR improved the accuracy of detection using panoramic images.

  17. Effectiveness of digital subtraction radiography in detecting artificially created osteophytes and erosions in the temporomandibular joint

    Science.gov (United States)

    Celenk, Peruze

    2017-01-01

    Purpose Erosions and osteophytes are radiographic characteristics that are found in different stages of temporomandibular joint (TMJ) osteoarthritis. This study assessed the effectiveness of digital subtraction radiography (DSR) in diagnosing simulated osteophytes and erosions in the TMJ. Materials and Methods Five intact, dry human skulls were used to assess the effectiveness of DSR in detecting osteophytes. Four cortical bone chips of varying thicknesses (0.5 mm, 1.0 mm, 1.5 mm, and 2.0 mm) were placed at the medial, central, and lateral aspects of the condyle anterior surface. Two defects of varying depth (1.0 mm and 1.5 mm) were created on the lateral, central, and medial poles of the condyles of 2 skulls to simulate erosions. Panoramic images of the condyles were acquired before and after artificially creating the changes. Digital subtraction was performed with Emago dental image archiving software. Five observers familiar with the interpretation of TMJ radiographs evaluated the images. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic accuracy of the imaging methods. Results The area under the ROC curve (Az) value for the overall diagnostic accuracy of DSR in detecting osteophytic changes was 0.931. The Az value for the overall diagnostic accuracy of panoramic imaging was 0.695. The accuracy of DSR in detecting erosive changes was 0.854 and 0.696 for panoramic imaging. DSR was remarkably more accurate than panoramic imaging in detecting simulated osteophytic and erosive changes. Conclusion The accuracy of panoramic imaging in detecting degenerative changes was significantly lower than the accuracy of DSR (Ppanoramic images. PMID:28680846

  18. Effectiveness of digital subtraction radiography in detecting artificially created osteophytes and erosions in the temporomandibular joint

    International Nuclear Information System (INIS)

    Kocasarac, Husniye Demirturk; Celenk, Peruze

    2017-01-01

    Erosions and osteophytes are radiographic characteristics that are found in different stages of temporomandibular joint (TMJ) osteoarthritis. This study assessed the effectiveness of digital subtraction radiography (DSR) in diagnosing simulated osteophytes and erosions in the TMJ. Five intact, dry human skulls were used to assess the effectiveness of DSR in detecting osteophytes. Four cortical bone chips of varying thicknesses (0.5 mm, 1.0 mm, 1.5 mm, and 2.0 mm) were placed at the medial, central, and lateral aspects of the condyle anterior surface. Two defects of varying depth (1.0 mm and 1.5 mm) were created on the lateral, central, and medial poles of the condyles of 2 skulls to simulate erosions. Panoramic images of the condyles were acquired before and after artificially creating the changes. Digital subtraction was performed with Emago dental image archiving software. Five observers familiar with the interpretation of TMJ radiographs evaluated the images. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic accuracy of the imaging methods. The area under the ROC curve (Az) value for the overall diagnostic accuracy of DSR in detecting osteophytic changes was 0.931. The Az value for the overall diagnostic accuracy of panoramic imaging was 0.695. The accuracy of DSR in detecting erosive changes was 0.854 and 0.696 for panoramic imaging. DSR was remarkably more accurate than panoramic imaging in detecting simulated osteophytic and erosive changes. The accuracy of panoramic imaging in detecting degenerative changes was significantly lower than the accuracy of DSR (P<.05). DSR improved the accuracy of detection using panoramic images

  19. The Cost of Joint Replacement: Comparing Two Approaches to Evaluating Costs of Total Hip and Knee Arthroplasty.

    Science.gov (United States)

    Palsis, John A; Brehmer, Thomas S; Pellegrini, Vincent D; Drew, Jacob M; Sachs, Barton L

    2018-02-21

    In an era of mandatory bundled payments for total joint replacement, accurate analysis of the cost of procedures is essential for orthopaedic surgeons and their institutions to maintain viable practices. The purpose of this study was to compare traditional accounting and time-driven activity-based costing (TDABC) methods for estimating the total costs of total hip and knee arthroplasty care cycles. We calculated the overall costs of elective primary total hip and total knee replacement care cycles at our academic medical center using traditional and TDABC accounting methods. We compared the methods with respect to the overall costs of hip and knee replacement and the costs for each major cost category. The traditional accounting method resulted in higher cost estimates. The total cost per hip replacement was $22,076 (2014 USD) using traditional accounting and was $12,957 using TDABC. The total cost per knee replacement was $29,488 using traditional accounting and was $16,981 using TDABC. With respect to cost categories, estimates using traditional accounting were greater for hip and knee replacement, respectively, by $3,432 and $5,486 for personnel, by $3,398 and $3,664 for space and equipment, and by $2,289 and $3,357 for indirect costs. Implants and consumables were derived from the actual hospital purchase price; accordingly, both methods produced equivalent results. Substantial cost differences exist between accounting methods. The focus of TDABC only on resources used directly by the patient contrasts with the allocation of all operating costs, including all indirect costs and unused capacity, with traditional accounting. We expect that the true costs of hip and knee replacement care cycles are likely somewhere between estimates derived from traditional accounting methods and TDABC. TDABC offers patient-level granular cost information that better serves in the redesign of care pathways and may lead to more strategic resource-allocation decisions to optimize

  20. Pneumatic Artificial Muscles Force Modelling and the Position and Stiffness Control on the Knee Joint of the Musculoskeletal Leg

    Directory of Open Access Journals (Sweden)

    Jingtao Lei

    2017-03-01

    Full Text Available Pneumatic artificial muscles (PAMs have properties similar to biological muscle and are widely used in robotics as actuators. A musculoskeletal leg mechanism driven by PAMs is presented in this paper. The joint stiffness of the musculoskeletal bionic leg for jumping movement needs to be analysed. The synchronous control on the position and stiffness of the joint is important to improve the flexibility of leg. The accurate force model of PAM is the foundation to achieving better control and dynamic jumping performance. The experimental platform of PAM is conducted, and the static equal pressure experiments are performed to obtain the PAM force model. According to the testing data, parameter identification method is adopted to determine the force model of PAM. A simulation on the position and stiffness control of the knee joint is performed, and the simulation results show the effectiveness of the presented method.

  1. The effect of sliding velocity on the mechanical response of an artificial joint in Topopah Spring Member tuff

    International Nuclear Information System (INIS)

    Olsson, W.A.

    1994-04-01

    A smooth artificial joint in Topopah Spring Member tuff was sheared at constant normal stress at velocities from 0 to 100 μm/s to determine the velocity-dependence of shear strength. Two different initial conditions were used: (1) unprimed -- the joint had been shear stress-free since last application of normal stress, and before renewed shear loading; and (2) primed -- the joint had undergone a slip history after application of normal stress, but before the current shear loading. Observed steady-state rate effects were found to be about 3 times lager than for some other silicate rocks. These different initial conditions affected the character of the stress-slip curve immediately after the onset of slip. Priming the joint causes a peak in the stress-slip response followed by a transient decay to the steady-state stress, i.e., slip weakening. Slide-hold-slide tests exhibit time-dependent strengthening. When the joint was subjected to constant shear stress, no slip was observed; that is, joint creep did not occur. One set of rate data was collected from a surface submerged in tap water, the friction was higher for this surface, but the rate sensitivity was the same as that for surfaces tested in the air-dry condition

  2. OARSI/OMERACT initiative to define states of severity and indication for joint replacement in hip and knee osteoarthritis. An OMERACT 10 Special Interest Group

    DEFF Research Database (Denmark)

    Gossec, Laure; Paternotte, Simon; Bingham, Clifton O

    2011-01-01

    To define pain and physical function cutpoints that would, coupled with structural severity, define a surrogate measure of "need for joint replacement surgery," for use as an outcome measure for potential structure-modifying interventions for osteoarthritis (OA)....

  3. Metabolic Effects of Replacing Sugar-Sweetened Beverages with Artificially-Sweetened Beverages in Overweight Subjects with or without Hepatic Steatosis: A Randomized Control Clinical Trial

    OpenAIRE

    Campos, Vanessa; Despland, Camille; Brandejsky, Vaclav; Kreis, Roland; Schneiter, Philippe; Boesch, Chris; Tappy, Luc

    2017-01-01

    OBJECTIVE Addition of fructose to the diet of normal weight and overweight subjects can increase postprandial plasma triglyceride and uric acid concentration. We, therefore, assessed whether replacing sugar-sweetened beverages (SSB) with artificially-sweetened beverages (ASB) in the diet of overweight and obese subjects would decrease these parameters. METHODS Twenty-six participants of the REDUCS study, which assessed the effects of replacing SSB by ASB over 12 weeks on intra-hep...

  4. Comparing contemporary revision burden among hip and knee joint replacement registries

    Directory of Open Access Journals (Sweden)

    Brian J. McGrory, MD, MS

    2016-06-01

    Conclusions: Revision burden has gradually decreased for hip replacements and has remained relatively constant for knee replacements both for the last 4 years and compared to historic controls. Knee revision burden was lower than hip revision burden for each period examined. Revision burden is one measure that may be helpful in following the effect of changes in surgical technique and implant design over time in registry populations and may be a helpful way to compare overall results between registries.

  5. Wear of cross-linked polyethylene against itself: a material suitable for surface replacement of the finger joint.

    Science.gov (United States)

    Sibly, T F; Unsworth, A

    1991-05-01

    Cross-linking of polyethylene (XLPE) has dramatically improved its properties in industrial applications, and it may also have some application in the field of human joint replacement. Additionally it has the advantage of permitting a lower molecular weight base material to be used, so that components may be injection moulded rather than machined. This study therefore investigates the wear resistance of medical grade cross-linked polyethylene (XLPE), cross-linked by a silane-grafting process, with a molecular weight between cross links of 5430 g mol(-1). This first report investigates the wear resistance of XLPE against itself, because for certain joints, such as the metacarpo-phalangeal joint, the material may have a high enough wear resistance to allow both bearing surfaces to be made from it. Tests were carried out both on a reciprocating pin and plate machine with pins loaded at 10 and 40 N and also on a new finger joint simulator, which simulates the loads applied to and the movements of, the metacarpo-phalangeal joint. An average wear rate of 1.8 x 10(-6) mm3 N-1 m-1 was found (range 0.9-2.75 x 10(-6) mm3 N-1 m-1). This is about six times greater than the wear rate of non-cross-linked ultra high molecular weight polyethylene (UHMWPE) against stainless steel, but for applications with low loading, such as the metacarpo-phalangeal joint, this material is shown to have adequate wear resistance. The coefficient of friction was 0.1, which is similar to that of UHMWPE on stainless steel.

  6. OMERACT/OARSI initiative to define states of severity and indication for joint replacement in hip and knee osteoarthritis

    DEFF Research Database (Denmark)

    Gossec, Laure; Hawker, Gillian; Davis, Aileen M

    2007-01-01

    . For structure, a comparison of existing indices (Kellgren-Lawrence, OARSI stages, and joint space width) was performed for the hip and the knee. RESULTS: For pain, key features of pain that are most distressing to people with OA from early to late disease were identified. For function, the reduction...... were used. For function, Rasch analysis was performed on existing indices the Hip Dysfunction and Osteoarthritis Outcome Score (HOOS) and the Knee injury and Osteoarthritis Outcome Score (KOOS), each of which subsumes the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) questions......OBJECTIVE: Time to theoretical indication of joint replacement surgery has been proposed as a primary outcome for potential structure-modifying interventions for osteoarthritis (OA). The objectives of this OMERACT/OARSI Working Group were to identify pain, physical function, and structure states...

  7. Measurement of installation deformation of the acetabulum during prosthetic replacement of a hip joint using digital image correlation

    Science.gov (United States)

    Lei, Dong; Bai, Pengxiang; Zhu, Feipeng

    2018-01-01

    Nowadays, acetabulum prosthesis replacement is widely used in clinical medicine. However, there is no efficient way to evaluate the implantation effect of the prosthesis. Based on a modern photomechanics technique called digital image correlation (DIC), the evaluation method of the installation effect of the acetabulum was established during a prosthetic replacement of a hip joint. The DIC method determines strain field by comparing the speckle images between the undeformed sample and the deformed counterpart. Three groups of experiments were carried out to verify the feasibility of the DIC method on the acetabulum installation deformation test. Experimental results indicate that the installation deformation of acetabulum generally includes elastic deformation (corresponding to the principal strain of about 1.2%) and plastic deformation. When the installation angle is ideal, the plastic deformation can be effectively reduced, which could prolong the service life of acetabulum prostheses.

  8. The association between ambulatory activity, body composition and hip or knee joint replacement due to osteoarthritis: a prospective cohort study.

    Science.gov (United States)

    Munugoda, I P; Wills, K; Cicuttini, F; Graves, S E; Lorimer, M; Jones, G; Callisaya, M L; Aitken, D

    2018-02-21

    To examine the association between ambulatory activity (AA), body composition measures and hip or knee joint replacement (JR) due to osteoarthritis. At baseline, 1082 community-dwelling older-adults aged 50-80 years were studied. AA was measured objectively using pedometer and body composition by dual-energy X-ray absorptiometry. The incidence of primary (first-time) JR was determined by data linkage to the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR). Log binomial regression with generalized estimating equations were used to estimate the risk of JR associated with baseline AA and body composition measures, adjusting for age, sex, X-ray disease severity, and pain. Over 13 years of follow-up, 74 (6.8%) participants had a knee replacement (KR) and 50 (4.7%) a hip replacement (HR). AA was associated with a higher risk of KR (RR 1.09/1000 steps/day, 95% CI 1.01, 1.16) and a lower risk of HR (RR 0.90/1000 steps/day, 95% CI 0.81, 0.99). Body mass index (BMI) (RR 1.07/kg/m 2 , 95% CI 1.03, 1.12), total fat mass (RR 1.04/kg, 95% CI 1.02, 1.07), trunk fat mass (RR 1.04/kg, 95% CI 1.02, 1.07), and waist circumference (RR 1.03/cm, 95% CI 1.01, 1.05) were associated with a higher risk of KR. Body composition measures were not associated with HR. An objective measure of AA was associated with a small increased risk of KR and a small reduced risk of HR. Worse body composition profiles were associated with knee, but not HR. Altogether this may suggest different causal pathways for each site with regard to habitual activity and obesity. Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  9. A New Approach for Human Forearm Motion Assist by Actuated Artificial Joint-An Inner Skeleton Robot

    Science.gov (United States)

    Kundu, Subrata Kumar; Kiguchi, Kazuo; Teramoto, Kenbu

    In order to help the physical activities of the elderly or physically disabled persons, we propose a new concept of a power-assist inner skeleton robot (i.e., actuated artificial joint) that is supposed to assist the human daily life motion from inside of the human body. This paper presents an implantable 2 degree of freedom (DOF) inner skeleton robot that is designed to assist human elbow flexion-extension motion and forearm supination-pronation motion for daily life activities. We have developed a prototype of the inner skeleton robot that is supposed to assist the motion from inside of the body and act as an actuated artificial joint. The proposed system is controlled based on the activation patterns of the electromyogram (EMG) signals of the user's muscles by applying fuzzy-neuro control method. A joint actuator with angular position sensor is designed for the inner skeleton robot and a T-Mechanism is proposed to keep the bone arrangement similar to the normal human articulation after the elbow arthroplasty. The effectiveness of the proposed system has been evaluated by experiment.

  10. A Qualitative Study of Factors Underlying Decision Making for Joint Replacement among African Americans and Latinos with Osteoarthritis

    Science.gov (United States)

    Parks, Michael L.; Hebert-Beirne, Jennifer; Rojas, Mary; Tuzzio, Leah; Nelson, Charles L.; Boutin-Foster, Carla

    2015-01-01

    To support patients in making decisions that align with their unique cultural beliefs, an understanding of factors underlying patient preferences is needed. We sought to identify psychosocial factors that influenced decision making among African-American and Hispanic patients referred for knee or hip arthroplasty. Thirty-six participants deciding on surgery were interviewed. Responses were audio-taped, transcribed, and read. Codes were assigned to the raw data and then clustered into categories that were analyzed to yield overarching themes. This process was repeated independently by two corroborators. Six categories described the mental calculations made in patients' decision-making processes: 1) self-assessment of ft for surgery based on age and comorbidity, 2) research and development of mental report cards of their surgeons, 3) reliving of social network experiences, 4) reliance on faith and spirituality for guidance, 5) acknowledgment of fear and anxiety, and 6) setting expectations for recovery. This study advanced the understanding of how decisions about joint replacement are constructed and identified cultural levers that can be targeted for intervention. Developing culturally tailored health information that addresses some of our findings and disseminating messages through social networks may reduce the underutilization of joint replacement among racial and ethnic minority populations. PMID:25272219

  11. The biological response to orthopedic implants for joint replacement. II: Polyethylene, ceramics, PMMA, and the foreign body reaction.

    Science.gov (United States)

    Gibon, Emmanuel; Córdova, Luis A; Lu, Laura; Lin, Tzu-Hua; Yao, Zhenyu; Hamadouche, Moussa; Goodman, Stuart B

    2017-08-01

    Novel evidence-based prosthetic designs and biomaterials facilitate the performance of highly successful joint replacement (JR) procedures. To achieve this goal, constructs must be durable, biomechanically sound, and avoid adverse local tissue reactions. Different biomaterials such as metals and their alloys, polymers, ceramics, and composites are currently used for JR implants. This review focuses on (1) the biological response to the different biomaterials used for TJR and (2) the chronic inflammatory and foreign-body response induced by byproducts of these biomaterials. A homeostatic state of bone and surrounding soft tissue with current biomaterials for JR can be achieved with mechanically stable, infection free and intact (as opposed to the release of particulate or ionic byproducts) implants. Adverse local tissue reactions (an acute/chronic inflammatory reaction, periprosthetic osteolysis, loosening and subsequent mechanical failure) may evolve when the latter conditions are not met. This article (Part 2 of 2) summarizes the biological response to the non-metallic materials commonly used for joint replacement including polyethylene, ceramics, and polymethylmethacrylate (PMMA), as well as the foreign body reaction to byproducts of these materials. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1685-1691, 2017. © 2016 Wiley Periodicals, Inc.

  12. [Stress analysis of artificial bionic knee joint based on UG6.0 NX NASTRAN].

    Science.gov (United States)

    Shi, Gengqiang

    2014-02-01

    This article introduces the basic principles of finite element analysis in biomechanics, focusing on the basic principles of a variety of finite element analysis software, and their respective characteristics. In addition, it also de scribes the basic stress analysis of UGNX6.0 NASTRAN analysis for artificial knee process, i. e. the choice of the type, material definition, the set of constants, finite element mesh division and the finite element results of the analysis. Finite element analysis and evaluation of the design of personalized artificial knee were carried out, so that the rationality of the geometric design of the structure of the experimental design of artificial knee has been verified.

  13. Mechanistic and morphological origins of ultra-high molecular weight polyethylene wear debris in total joint replacement prostheses.

    Science.gov (United States)

    Wang, A; Stark, C; Dumbleton, J H

    1996-01-01

    The mechanistic and morphological origins of microscopic wear debris generated from UHMWPE articular surfaces in total joint replacement prostheses are investigated in this study. It was found experimentally that the molecular chain structure at the articulating surface of UHMWPE undergoes a re-organization process due to strain accumulation caused by surface traction. This molecular re-organization process creates a fibre-like surface texture that exhibits an anisotropic behaviour similar to a unidirectionally reinforced polymer composite. This composite responds to stresses favourably if loaded along the fibre axis but unfavourably if loaded off axis. Due to the very complex multi-axial motion/loading nature at the articular surfaces in total joint replacements, the stress tensors applied to each localized asperity contact area continuously change their directions and magnitudes. These changes in the localized stress field create an off-axis loading situation at each localized contact zone with respect to the orientation of the molecular chains. Depending on the off-axis angle, failure of the molecular structure occurs in three different ways: tensile rupture at very small off-axis angles, shear rupture at intermediate off-axis angles and transverse splitting at large off-axis angles. These failure mechanisms all produce similar fibre-like wear debris. However, the failure stresses differ significantly among the three modes. According to this molecular wear theory, the preferred polymer microstructure for optimal wear resistance would be a three-dimensionally strong network connected by covalent bonds between molecular chains. For UHMWPE, a three-dimensional molecular network can be created by radiation induced cross-linking. Experiments conducted on both gamma irradiated and unirradiated UHMWPE specimens using a linear wear machine and multi-axial joint simulators confirmed the validity of the molecular wear theory.

  14. Stereo-radiographic analysis of loosening processes of alloplastic hip joint replacement

    International Nuclear Information System (INIS)

    Probst, K.J.

    1980-01-01

    A computer-aided diagnostic system has been developed by which implant dislocation of an order of 0.2 mm can be detected in all three dimensions. The diagnostic system is based on a point-by-point evaluation of stereoradiographic pictures; precise localisation of the implant relative to its place of insertion is made possible by special mathematical operations which are discussed in detail in the methodical part of the book. The method has been tested in clinical practice in 351 cases (208 patients) in the period between September 1, 1977, and May 31, 1979. By taking functional pictures during adduction and abduction of the extremity carrying the endoprosthesis and then evaluating these pictures, the diagnostic system can detect dislocations of the endoprosthesis inside the bone at a given moment. Also, the fate of hip joints with endoprostheses can be followed in the framework of longitudinal research. The method described here may also help to solve other problems of clinical relevance. The only precondition for this is the imaging of the structures of interest in the X-ray picture. A program to analyze loosening processes of alloplastic knee joint implants is new being worked on which will be of great use to the increasing number of patients with alloplastic knee joint implants. (orig./MG) [de

  15. Artificial Cervical Disk Replacement for the Treatment of Adjacent Segment Disease After Anterior Cervical Decompression and Fusion.

    Science.gov (United States)

    Bin, Sheng; Xiangwang, Huang; Sheng, Xiao; Tiecheng, Xiang; Xiangyang, Liu; Yi, Zhang; Bin, Liu

    2017-06-01

    Retrospective study. To evaluate the outcome of artificial cervical disk replacement (ACDR) for the treatment of adjacent segment disease (ASD) after anterior cervical decompression and fusion (ACDF). ACDF is the useful procedure for degenerative cervical diseases. However, studies have reported accelerated degeneration of functional spinal units adjacent to the fusion site after ACDF. Between January 2004 and January 2011, 32 inpatients (18 male, 14 female; age, 38-61 y; mean, 48 y) underwent ACDR for the treatment of ASD after previous ACDF (single-level: n=12; 2-level: n=15; 3-level: n=5). In 22 patients, ASD occurred above the fusion site, and in 10 it occurred below the site. After ACDR, the patients were followed up for 30-62 months (mean, 49 mo). Before and after ACDR, patients were evaluated using the pain visual analog scale (VAS), the Japanese Orthopedic Association (JOA) score, and neck disability index (NDI). In addition, the range of motion (ROM) of the replaced and adjacent unfused segments was measured by flexion/extension lateral radiography. Periprosthetic heterotopic ossification was detected using McAfee's classification. Degeneration of the adjacent unfused segment was evaluated using Goffin scale. All patients had successful surgery. Before ACDR, neck VAS, upper-limb VAS, JOA score, and NDI were 7.2±1.8, 6.9±1.1, 9.8±2.5, and 40.5±4.8, respectively. At the last follow-up, they were 1.2±0.3, 0.9±0.3, 14.5±1.1, and 9.0±2.5, respectively. Compared with presurgery, the improvements in VAS, JOA score, and NDI at the final follow-up were statistically significant (all P0.05). At the last follow-up, 2 patients had grade II heterotopic ossification; 3 patients had aggravated degeneration (vs. preoperative status) of the adjacent unfused segment. However, the reduction in Goffin grade was not statistically significant. Our follow-up shows that ACDR is an effective treatment for post-ACDF ASD. It can maintain the ROMs of the replaced segment as

  16. Geographic region, socioeconomic position and the utilisation of primary total joint replacement for hip or knee osteoarthritis across western Victoria: a cross-sectional multilevel study of the Australian Orthopaedic Association National Joint Replacement Registry.

    Science.gov (United States)

    Brennan-Olsen, Sharon; Vogrin, Sara; Holloway, Kara L; Page, Richard S; Sajjad, Muhammad A; Kotowicz, Mark A; Livingston, Patricia M; Khasraw, Mustafa; Hakkennes, Sharon; Dunning, Trish L; Brumby, Susan; Pedler, Daryl; Sutherland, Alasdair; Venkatesh, Svetha; Williams, Lana J; Duque, Gustavo; Pasco, Julie A

    2017-11-06

    Compared to urban residents, those in rural/regional areas often experience inequitable healthcare from specialist service providers. Independent of small between-area differences in utilisation, socially advantaged groups had the greatest uptake of joint replacement. These data suggest low correlation between 'need' vs. 'uptake' of surgery in rural/regional areas. Compared to urban residents, those in rural and regional areas often experience inequitable healthcare from specialist service providers, often due to geographical issues. We investigated associations between socioeconomic position (SEP), region of residence and utilisation of primary total knee replacement (TKR) and/or total hip replacement (THR) for osteoarthritis. As part of the Ageing, Chronic Disease and Injury study, we extracted data from the Australian Orthopaedic Association National Joint Replacement Registry (2011-2013) for adults that utilised primary TKR (n = 4179; 56% female) and/or THR (n = 3120; 54% female). Residential addresses were matched with the Australian Bureau of Statistics (ABS) 2011 census data: region of residence was defined according to local government areas (LGAs), and area-level SEP (quintiles) defined using an ABS-derived composite index. The ABS-determined control population (n = 591,265; 51% female) excluded individuals identified as cases. We performed multilevel logistic regression modelling using a stratified two-stage cluster design. TKR was higher for those aged 70-79 years (AOR 1.4 95%CI 1.3-1.5; referent = 60-69 years) and in the most advantaged SEP quintile (AOR 2.1, 95%CI 1.8-2.3; referent = SEP quintile 3); results were similar for THR (70-79 years = AOR 1.7, 95%CI 1.5-1.8; SEP quintile 5 = AOR 2.5, 95%CI 2.2-2.8). Total variances contributed by the variance in LGAs were 2% (SD random effects ± 0.28) and 3% (SD ± 0.32), respectively. Independent of small between-LGA differences in utilisation, and in contrast to the expected greater

  17. Total joint replacement for neglected posterior knee dislocation following septic arthritis after arthroscopy

    Directory of Open Access Journals (Sweden)

    Yusuf Öztürkmen

    2017-07-01

    Full Text Available This report presents the first case of a knee dislocation following septic arthritis after arthroscopy. A 65-year-old woman had an arthroscopy with irrigation and debridement (I&D of the joint and microfracture for the chondral lesions. She had complaints of postarthroscopic infection but non-steroidal anti-inflammatory medication and local ice compression was recommended. She revisited her physician twice and at the last visit she had a large purulent effusion in her knee. The gram stain of the joint fluid aspirate demonstrated gram-positive cocci and the cultures grew methicilline-sensitive Staphylococcus aureus. She underwent arthroscopic assisted I&D and received intravenous antibiotics. I&D was repeated after two weeks. Intravenous antibiotherapy was continued for one more week and was changed to oral antibiotherapy for six weeks. At the third month visit's physical examination, a deformity at the knee was noticed and was referred to us for further treatment. A posterior knee dislocation with no neurovascular deficit was detected. The patient had a history of knee sprain but did not seek medical advice immediately. The blood samples showed no abnormality. The patient underwent a surgery with a cemented hinged revision total knee prosthesis following the exclusion of the active knee joint infection. Intraoperative frozen sections were also taken to exclude the active infection. The patient's knee is pain-free with full range of motion after 3 years. The objective of this report was to highlight the importance of early diagnosis, prompt appropriate treatment of septic arthritis following arthroscopy and the awareness of the knee dislocation as a rare dreadful complication of postarthroscopic infection particularly in elderly patients.

  18. Total joint replacement for neglected posterior knee dislocation following septic arthritis after arthroscopy.

    Science.gov (United States)

    Öztürkmen, Yusuf; Akman, Yunus Emre; Ünkar, Ethem Ayhan; Şükür, Erhan

    2017-07-01

    This report presents the first case of a knee dislocation following septic arthritis after arthroscopy. A 65-year-old woman had an arthroscopy with irrigation and debridement (I&D) of the joint and microfracture for the chondral lesions. She had complaints of postarthroscopic infection but non-steroidal anti-inflammatory medication and local ice compression was recommended. She revisited her physician twice and at the last visit she had a large purulent effusion in her knee. The gram stain of the joint fluid aspirate demonstrated gram-positive cocci and the cultures grew methicilline-sensitive Staphylococcus aureus. She underwent arthroscopic assisted I&D and received intravenous antibiotics. I&D was repeated after two weeks. Intravenous antibiotherapy was continued for one more week and was changed to oral antibiotherapy for six weeks. At the third month visit's physical examination, a deformity at the knee was noticed and was referred to us for further treatment. A posterior knee dislocation with no neurovascular deficit was detected. The patient had a history of knee sprain but did not seek medical advice immediately. The blood samples showed no abnormality. The patient underwent a surgery with a cemented hinged revision total knee prosthesis following the exclusion of the active knee joint infection. Intraoperative frozen sections were also taken to exclude the active infection. The patient's knee is pain-free with full range of motion after 3 years. The objective of this report was to highlight the importance of early diagnosis, prompt appropriate treatment of septic arthritis following arthroscopy and the awareness of the knee dislocation as a rare dreadful complication of postarthroscopic infection particularly in elderly patients. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  19. New total ossicular replacement prostheses with a resilient joint: experimental data from human temporal bones.

    Science.gov (United States)

    Arechvo, Irina; Bornitz, Matthias; Lasurashvili, Nikoloz; Zahnert, Thomas; Beleites, Thomas

    2012-01-01

    New flexible total ossicular prostheses with an integrated microjoint can compensate for large static displacements in the reconstructed ossicular chain. When properly designed, they can mimic the function of the joints of the intact chain and ensure good vibration transfer in both straight and bent conditions. Prosthesis dislocations and extrusions are frequently observed after middle ear surgery. They are mainly related to the altered distance between the coupling points because of large static eardrum displacements. The new prostheses consist of 2 titanium shafts, which are incorporated into a silicone body. The sound transfer function and stapes footplate displacement at static loads were evaluated in human temporal bones after ossicular reconstruction using prostheses with 2 different silicones with different hardness values. The stiffness and bending characteristics of the prostheses were investigated with a quasi-static load. The sound transfer properties of the middle ears with the prostheses inserted under uncompressed conditions were comparable with those of ears with intact ossicular chains. The implant with the soft silicone had improved acoustic transfer characteristics over the implant with the hard silicone in a compressed state. In the quasi-static experiments, the minimum medial footplate displacement was found with the same implant. The bending characteristics depended on the silicone stiffness and correlated closely with the point and angle of the load incidence. The titanium prostheses with a resilient joint that were investigated in this study had good sound transfer characteristics under optimal conditions as well as in a compressed state. As a result of joint bending, the implants compensate for the small changes in length of the ossicular chain that occur under varying middle ear pressure. The implants require a stable support at the stapes footplate to function properly.

  20. Radionuclide imaging of the painful joint replacement: past, present and future

    International Nuclear Information System (INIS)

    Palestro, Christopher J.

    2002-01-01

    Differentiating aseptic loosening from infection as the cause of prosthetic joint failure is difficult because both entities are similar, clinically and histopathologically. Aseptic loosening frequently result from an immune reaction to the prosthesis. There is inflammation with an influx of histiocytes, giant cells, lymphocytes and plasma cells. Pro inflammatory cytokines and proteolytic enzymes are secreted, causing osteolysis and loosening. These same events occur in infection except that neutrophils, rarely present in aseptic loosening, area invariably present in infection. Clinical signs and symptoms, laboratory tests, X-rays and joint aspiration are insensitive, nonspecific or both. Artifacts produced by the metallic hardware hamper cross-sectional imaging modalities. Radionuclide imaging is not affected by the presence of metallic hardware and is very useful for evaluating the painful prosthesis. Bone scintigraphy, with and accuracy of 50%-70% is a useful screening test, since a normal study effectively excludes a prosthetic complication. Adding gallium-67, a nonspecific inflammation-imaging agent, improves the accuracy of bone scintigraphy to 70%-80%. The accuracy of combined leukocyte/marrow imaging, 90%, is the highest among available radionuclide studies. Its success is due to the fact that leukocytes imaging is most sensitive for detecting neutrophil mediated inflammations. Inflammatory conditions that are neutrophil-poor, even though large numbers of other leukocytes may be present, (such as the aseptically loosened joint prosthesis) go undetected. The success of leukocyte/marrow imaging is tempered by the limitations of in vitro labeling. In vivo labeling has been investigated and a murine monoclonal anti-granulocyte antibody appears promising. Some investigations have focused on F-18 FDG imaging, although specificity is a concern with this agent. (author)

  1. Radionuclide imaging of the painful joint replacement: past, present and future

    Energy Technology Data Exchange (ETDEWEB)

    Palestro, Christopher J. [Long Island Jewish Medical Center, New Hyde Park, NY (United States)]. E-mail: palestro@lij.edu

    2002-09-01

    Differentiating aseptic loosening from infection as the cause of prosthetic joint failure is difficult because both entities are similar, clinically and histopathologically. Aseptic loosening frequently result from an immune reaction to the prosthesis. There is inflammation with an influx of histiocytes, giant cells, lymphocytes and plasma cells. Pro inflammatory cytokines and proteolytic enzymes are secreted, causing osteolysis and loosening. These same events occur in infection except that neutrophils, rarely present in aseptic loosening, area invariably present in infection. Clinical signs and symptoms, laboratory tests, X-rays and joint aspiration are insensitive, nonspecific or both. Artifacts produced by the metallic hardware hamper cross-sectional imaging modalities. Radionuclide imaging is not affected by the presence of metallic hardware and is very useful for evaluating the painful prosthesis. Bone scintigraphy, with and accuracy of 50%-70% is a useful screening test, since a normal study effectively excludes a prosthetic complication. Adding gallium-67, a nonspecific inflammation-imaging agent, improves the accuracy of bone scintigraphy to 70%-80%. The accuracy of combined leukocyte/marrow imaging, 90%, is the highest among available radionuclide studies. Its success is due to the fact that leukocytes imaging is most sensitive for detecting neutrophil mediated inflammations. Inflammatory conditions that are neutrophil-poor, even though large numbers of other leukocytes may be present, (such as the aseptically loosened joint prosthesis) go undetected. The success of leukocyte/marrow imaging is tempered by the limitations of in vitro labeling. In vivo labeling has been investigated and a murine monoclonal anti-granulocyte antibody appears promising. Some investigations have focused on F-18 FDG imaging, although specificity is a concern with this agent. (author)

  2. A systematic review of endoprosthetic replacement for non-tumour indications around the knee joint.

    Science.gov (United States)

    Korim, Muhammad T; Esler, Colin N A; Reddy, Venuthurla R M; Ashford, Robert U

    2013-12-01

    Endoprosthetic replacement (EPR) for limb salvage is an established treatment modality for orthopaedic malignancies around the knee. Increasingly, they are being used for non-tumour indications such as fractures, bone loss associated with aseptic loosening, septic loosening and ligament insufficiencies. We reviewed the evolution and biomechanics of knee EPRs. MEDLINE was searched using the PubMed interface to identify relevant studies pertaining to the use of knee EPRs in non-tumour conditions. Failures, mortality and knee scores were the main outcome measures. Subgroup analysis in the non-tumour conditions was also performed. There were nine studies with an average follow-up of 3.3years (Range 1-5years) describing 241 EPRs used in non-tumour conditions. Re-operation for any reason occurred in 17% (41/241) of cases. The most common complication was infection (15%) followed by aseptic loosening (5%) and periprosthetic fractures (5%). The mortality rate averaged 22%. Infected knee arthroplasties were less likely to have a successful outcome when salvaged with an EPR with failure rates up to 33%. Endoprosthetic replacement is a limb salvage option when other surgical options are unfeasible, especially in low demand elderly patients with limited life expectancy. They have low rates of failure in the medium term. Level 1. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Noninvasive Hemoglobin Monitoring: A Rapid, Reliable, and Cost-Effective Method Following Total Joint Replacement.

    Science.gov (United States)

    Martin, J Ryan; Camp, Christopher L; Stitz, Amber; Young, Ernest Y; Abdel, Matthew P; Taunton, Michael J; Trousdale, Robert T

    2016-03-02

    Noninvasive hemoglobin (nHgb) monitoring was initially introduced in the intensive care setting as a means of rapidly assessing Hgb values without performing a blood draw. We conducted a prospective analysis to compare reliability, cost, and patient preference between nHgb monitoring and invasive Hgb (iHgb) monitoring performed via a traditional blood draw. We enrolled 100 consecutive patients undergoing primary or revision total hip or total knee arthroplasty. On postoperative day 1, nHgb and iHgb values were obtained within thirty minutes of one another. iHgb and nHgb values, cost, patient satisfaction, and the duration of time required to obtain each reading were recorded. The concordance correlation coefficient (CCC) was utilized to evaluate the agreement of the two Hgb measurement methods. Paired t tests and Wilcoxon signed-rank tests were utilized to compare mean Hgb values, time, and pain for all readings. The mean Hgb values did not differ significantly between the two measurement methods: the mean iHgb value (and standard deviation) was 11.3 ± 1.4 g/dL (range, 8.2 to 14.3 g/dL), and the mean nHgb value was 11.5 ± 1.8 g/dL (range, 7.0 to 16.0 g/dL) (p = 0.11). The CCC between the two Hgb methods was 0.69. One hundred percent of the patients with an nHgb value of ≥ 10.5 g/dL had an iHgb value of >8.0 g/dL. The mean time to obtain an Hgb value was 0.9 minute for the nHgb method and 51.1 minutes for the iHgb method (p measurement, resulting in a savings of $26 per Hgb assessment when the noninvasive method is used. Noninvasive Hgb monitoring was found to be more efficient, less expensive, and preferred by patients compared with iHgb monitoring. Providers could consider screening total joint arthroplasty patients with nHgb monitoring and only order iHgb measurement if the nHgb value is protocol had been applied to the first blood draw in our 100 patients, approximately $2000 would have been saved. Extrapolated to the U.S. total joint arthroplasty practice

  4. Experimental and thermodynamic studies of beryllium replacement materials for CANDU brazed joints

    International Nuclear Information System (INIS)

    Potter, K.N.; Ferrier, G.A.; Corcoran, E.C.

    2015-01-01

    Currently, appendages are joined to CANDU fuel elements via a brazing process, which uses beryllium as the filler material. A potential reduction in the occupational limit on airborne beryllium particulates has motivated research into alternative brazing materials. To this end, the Canadian nuclear industry has funded an initiative to identify and evaluate the suitability of several candidate materials. This work describes contributions toward the assessment of alternative brazing materials from the Royal Military College of Canada. Thermodynamic modelling was performed to predict the aqueous behaviour of each candidate material in CANDU coolant conditions characteristic of reactor shutdown, and experiments are underway to support modelling predictions. These results will assist in selecting a suitable replacement material for beryllium. (author)

  5. Massachusetts health reform and disparities in joint replacement use: difference in differences study.

    Science.gov (United States)

    Hanchate, Amresh D; Kapoor, Alok; Katz, Jeffrey N; McCormick, Danny; Lasser, Karen E; Feng, Chen; Manze, Meredith G; Kressin, Nancy R

    2015-02-20

    To estimate the impact of the insurance expansion in 2006 on use of knee and hip replacement procedures by race/ethnicity, area income, and the use of hospitals that predominantly serve poor people ("safety net hospitals"). Quasi-experimental difference in differences study examining change after reform in the share of procedures performed in safety net hospitals by race/ethnicity and area income, with adjustment for patients' residence, demographics, and comorbidity. State of Massachusetts, United States. Massachusetts residents aged 40-64 as the target beneficiaries of reform and similarly aged residents of New Jersey, New York, and Pennsylvania as the comparison (control) population. Number of knee and hip replacement procedures per 10 000 population and use of safety net hospitals. Procedure counts from state discharge data for 2.5 years before and after reform, and multivariate difference in differences. Poisson regression was used to adjust for demographics, economic conditions, secular time, and geographic factors to estimate the change in procedure rate associated with health reform by race/ethnicity and area income. Before reform, the number of procedures (/10 000) in Massachusetts was lower among Hispanic people (12.9, Preform in Massachusetts was associated with a 4.7% increase. The increase associated with reform was significantly higher among Hispanic people (37.9%, Preform. The reduction was larger among Hispanic people (-6.4%, P<0.001) than white people (-1.0%), and among low income residents (-3.9%, p<0.001) than high income residents (0%). Insurance expansion can help reduce disparities by race/ethnicity but not by income in access to elective surgical care and could shift some elective surgical care away from safety net hospitals. © Hanchate et al 2015.

  6. Quick bacteriophage-mediated bioluminescence assay for detecting Staphylococcus spp. in sonicate fluid of orthopaedic artificial joints.

    Science.gov (United States)

    Šuster, Katja; Podgornik, Aleš; Cör, Andrej

    2017-07-01

    Staphylococcus spp. accounts for up to two thirds of all microorganisms causing prosthetic joint infections, with Staphylococcus aureus and Staphylococcus epidermidis being the major cause. The present study describes a diagnostic model to detect staphylococci using a specific bacteriophage and bioluminescence detection, exploring the possibility of its use on sonicate fluid of orthopaedic artificial joints. Intracellular adenosine-5'-triphosphate release by bacteriophage mediated lysis of staphylococci was assessed to determine optimal parameters for detection. With the optimized method, a limit of detection of around 103 CFU/mL was obtained after incubation with bacteriophage for 2 h. Importantly, sonicate fluid did not prevent the ability of bacteriophage to infect bacteria and all simulated infected sonicate fluid as well as 6 clinical samples with microbiologically proven staphylococcal infection were detected as positive. The total assay took approximately 4 h. Collectively, the results indicate that the developed method promises a rapid, inexpensive and specific diagnostic detection of staphylococci in sonicate fluid of infected prosthetic joints. In addition, the unlimited pool of different existing bacteriophages, with different specificity for all kind of bacteria gives the opportunity for further investigations, improvements of the current model and implementation in other medical fields for the purpose of the establishment of a rapid diagnosis.

  7. Combination COX-2 inhibitor and metformin attenuate rate of joint replacement in osteoarthritis with diabetes: A nationwide, retrospective, matched-cohort study in Taiwan.

    Science.gov (United States)

    Lu, Chieh-Hua; Chung, Chi-Hsiang; Lee, Chien-Hsing; Hsieh, Chang-Hsun; Hung, Yi-Jen; Lin, Fu-Huang; Tsao, Chang-Huei; Hsieh, Po-Shiuan; Chien, Wu-Chien

    2018-01-01

    Osteoarthritis (OA) is the most common form of arthritis associated with an increased prevalence of type 2 diabetes mellitus (T2DM), however their impact on decreasing joint replacement surgery has yet to be elucidated. This study aimed to investigate if the combination of COX-2 inhibitor and metformin therapy in OA with T2DM were associated with lower the rate of joint replacement surgery than COX-2 inhibitor alone. In total, 968 subjects with OA and T2DM under COX-2 inhibitor and metformin therapy (case group) between 1 January to 31 December 2000 were selected from the National Health Insurance Research Database of Taiwan, along with 1936 patients were the 1:2 gender-, age-, and index year-controls matched without metformin therapy (control group) in this study. Cox proportional hazards analysis was used to compare the rate of receiving joint replacement surgery during 10 years of follow-up. At the end of follow-up, 438 of all enrolled subjects (15.08%) had received the joint replacement surgery, including 124 in the case group (12.81%) and 314 in the control group (16.22%). The case group tended to be associated with lower rate of receiving the joint replacement surgery at the end of follow-up than the control group (p = 0.003). Cox proportional hazards regression (HR) analysis revealed that study subjects under combination therapy with metformin had lower rate of joint replacement surgery (adjusted HR 0.742 (95% CI = 0.601-0.915, p = 0.005)). In the subgroups, study subjects in the combination metformin therapy who were female, good adherence (>80%), lived in the highest urbanization levels of residence, treatment in the hospital center and lower monthly insurance premiums were associated with a lower risk of joint replacement surgery than those without. Patients who have OA and T2DM receiving combination COX-2 inhibitors and metformin therapy associated with lower joint replacement surgery rates than those without and this may be attributable to combination

  8. The effect of local anaesthetic wound infiltration on chronic pain after lower limb joint replacement: A protocol for a double-blind randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Smith Alison J

    2011-02-01

    Full Text Available Abstract Background For the majority of patients with osteoarthritis (OA, joint replacement is a successful intervention for relieving chronic joint pain. However, between 10-30% of patients continue to experience chronic pain after joint replacement. Evidence suggests that a risk factor for chronic pain after joint replacement is the severity of acute post-operative pain. The aim of this randomised controlled trial (RCT is to determine if intra-operative local anaesthethic wound infiltration additional to a standard anaethesia regimen can reduce the severity of joint pain at 12-months after total knee replacement (TKR and total hip replacement (THR for OA. Methods 300 TKR patients and 300 THR patients are being recruited into this single-centre double-blind RCT. Participants are recruited before surgery and randomised to either the standard care group or the intervention group. Participants and outcome assessors are blind to treatment allocation throughout the study. The intervention consists of an intra-operative local anaesthetic wound infiltration, consisting of 60 mls of 0.25% bupivacaine with 1 in 200,000 adrenaline. Participants are assessed on the first 5 days post-operative, and then at 3-months, 6-months and 12-months. The primary outcome is the WOMAC Pain Scale, a validated measure of joint pain at 12-months. Secondary outcomes include pain severity during the in-patient stay, post-operative nausea and vomiting, satisfaction with pain relief, length of hospital stay, joint pain and disability, pain sensitivity, complications and cost-effectiveness. A nested qualitative study within the RCT will examine the acceptability and feasibility of the intervention for both patients and healthcare professionals. Discussion Large-scale RCTs assessing the effectiveness of a surgical intervention are uncommon, particulary in orthopaedics. The results from this trial will inform evidence-based recommendations for both short-term and long-term pain

  9. Reemplazo articular temporomandibular debido a queratoquiste odontogénico Temporomandibular joint replacement because of odontogenic keratocyst

    Directory of Open Access Journals (Sweden)

    Pedro Angel Peñón Vivas

    2013-03-01

    Full Text Available Existen disímiles condiciones que hacen necesario el reemplazo articular temporomandibular; dentro de las más frecuentes se encuentran la anquilosis, la osteoatrosis, estadíos avanzados del Síndrome de disfunción temporomandibular, daño articular postrauma y procesos neoplásicos o tumorales. Los queratoquistes odontógenos que se agrupan para su estudio dentro de los quistes odontogénicos del desarrollo, representan cerca del 7 al 10 por ciento de todos los quistes maxilo-mandibulares. Se dice que tienen dos picos de incidencia entre la segunda y tercera década de vida y entre los 50 y 60 años de edad, con una ligera predilección por el sexo masculino. Aparece más frecuentemente en la región del tercer molar de la mandíbula con extensión a la rama ascendente El presente trabajo tuvo como objetivo mostrar el caso de un paciente masculino de 57 años de edad en el que fue necesario el reemplazo articular temporomandibular debido a un queratoquiste odontogénico que involucraba la totalidad de la rama mandibular derecha, incluyendo el proceso condíleo y coronoideo, así como el ángulo hasta el tercio posterior del cuerpo mandibular. Tras un año de realizada la intervención quirúrgica la evolución del paciente fue satisfactoria.Temporomandibular joint replacement is required in a variety of conditions. Among the most frequent are ankylosis, osteoarthrosis, advanced stages of the temporomandibular dysfunction syndrome, post-traumatic joint damage, and neoplastic or tumoral processes. Odontogenic keratocysts, which are classified as developmental odontogenic cysts for study purposes, constitute 7-10 per cent of all maxillomandibular cysts. Two peaks have been identified in their incidence: between the second and third decades of life, and between 50 and 60 years of age, with a slight predominance of the male sex. They are most common in the third molar area of the mandibule, with expansion to the ascending branch. A case is

  10. Case study of physiotherapy treatment of a patient with the diagnosis of ankylosing spondylitis and status after total replacement of hip joint

    OpenAIRE

    Chlebečková, Helena

    2013-01-01

    Title: Case study of physiotherapy treatment of a patient with the diagnosis of ankylosing spondylitis and status after total replacement of hip joint Summary: This bachelor thesis deals with the problem of rheumatic disease ankylosing spondylitis and the effects of this disease. General part focuses on describing the theoretical knowledge of ankylosing spondylitis and possible methods for its treatment, and the implantation of hip replacement and subsequent rehabilitation. The special part p...

  11. Prospective Assessment of Sleep Quality Before and After Primary Total Joint Replacement.

    Science.gov (United States)

    Manning, Blaine T; Kearns, Sean M; Bohl, Daniel D; Edmiston, Tori; Sporer, Scott M; Levine, Brett R

    2017-07-01

    Sleep disruption is a common, yet rarely addressed, complaint among patients who have undergone total joint arthroplasty (TJA). This study assessed sleep quality before and after primary TJA. A total of 105 patients who underwent primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) prospectively completed questionnaires during the preoperative, early postoperative, and late postoperative periods. The survey included the Epworth Sleepiness Scale, current sleeping habits, and patient perspectives of sleep quality and duration. In the early postoperative period (4.7±2.0 weeks), patients reported significant increases in sleep disturbance as denoted by increased length of time to fall asleep (P=.006) and mean nightly awakenings (P=.002) compared with the preoperative baseline. At late postoperative follow-up (40.8±19.5 weeks), patients' sleep quality subsequently improved above the preoperative baseline. Approximately 40% of patients tried a new sleeping method postoperatively, the most common being new pillow placement. No significant differences in pre- or postoperative sleeping trends were noted between THA and TKA patients. These findings suggest transient sleep disturbance is common in the early postoperative period, with subsequent improvement by 10-month follow-up after a primary TJA. Given the growing importance of patient satisfaction in health care systems, orthopedic surgeons must manage patients' expectations while working with them to optimize sleep quality after TJA. A multimodal approach with preoperative counseling, early postoperative sleep modifications, and possibly preemptive use of medications may improve transient sleep disturbance among TJA patients. [Orthopedics. 2017; 40(4):e636-e640.]. Copyright 2017, SLACK Incorporated.

  12. The effect of lubricant constituents on lubrication mechanisms in hip joint replacements.

    Science.gov (United States)

    Nečas, David; Vrbka, Martin; Urban, Filip; Křupka, Ivan; Hartl, Martin

    2015-03-01

    The aim of the present paper is to provide a novel experimental approach enabling to assess the thickness of lubricant film within hip prostheses in meaning of the contribution of particular proteins. Thin film colorimetric interferometry was combined with fluorescent microscopy finding that a combination of optical methods can help to better understand the interfacial lubrication processes in hip replacements. The contact of metal femoral head against a glass disc was investigated under various operating conditions. As a test lubricant, the saline solution containing the albumin and γ-globulin in a concentration 2:1 was employed. Two different mean speeds were applied, 5.7 and 22mm/s, respectively. The measurements were carried out under pure rolling, partial negative and partial positive sliding conditions showing that kinematic conditions substantially affects the formation of protein film. Under pure rolling conditions, an increasing tendency of lubricant film independently on rolling speed was detected, while the total thickness of lubricant film can be attributed mainly to albumin. When the ball was faster than the disc (negative sliding), a very thin lubricant film was observed for lower speed with no significant effect of particular proteins. The increase in sliding speed led to the increase of film thickness mainly caused due to the presence of γ-globulin. On the contrary, when the disc was faster than the ball (positive sliding), the film formation was very complex and time dependent while both of the studied proteins have shown any qualitative change during the test, however the effect of albumin seems to be much more important. Since a very good agreement of the results was obtained, it can be concluded that the approach consisting of two optical methods can provide the fundamental information about the lubricant film formation in meaning of particular proteins while the simultaneous presence of other constituents in model synovial fluid. Copyright

  13. PERIPROSTHETIC INFECTION AFTER ENDOPROSTHETIC REPLACEMENT OF THE HIP JOINT IN PATIENTS WITH RHEUMATOID DISEASES

    Directory of Open Access Journals (Sweden)

    Vadim Petrovich Pavlov

    2013-01-01

    Full Text Available Periprosthetic infection (PI in patients with rheumatoid diseases (RD after total hip joint endoprosthesis (THJE is a relevant problem of rheumoorphopedics that has not been solved yet. The relative assessment of PI incidence rate after THJE and treatment outcomes in patients with this complication is expected to be carried out. A total of 1201 THJE performed in 1069 patients with RD are considered. The female : male ratio was 3.6 : 1; the mean age was 49.6 years (range: 16 to 83 years. 323 patients had rheumatoid arthritis (RA; 124 patients had juvenile rheumatoid arthritis (JRA; 80 patients had ankylosing spondylitis (AS; 79 patients had systemic lupus erythematosus (SLE; 11 patients had systemic sclerodermatitis (SSD; 18 patients had psoriatic arthropathy (PsA; and 353 patients had osteoarthritis (OA. Other RD were revealed in 81 patients. PI were detected in 9 (0.84% of 1069 patients with RD, including 7 (2.17% of 323 patients with RA; 1 (0.8% of 124 patients with JRA; and 1 (0.28% of 353 patients with OA. No PI were detected in 81 patients who had other RD. An eightfold (in patients with RA and a threefold (in patients with JRA increase in PI compared to that in patients with OA attests to the high risk of this complication in patients with inflammatory as compared to the patients with degenerative RD. After integrated treatment (revision surgery, sanation, continuous irrigation with antibiotics/lavasept, the graft was preserved in OA patients; the complication was prevented in RA patients. Six patients will be subjected to repeated revision surgery; one patient died of diabetes complications after the graft had been removed. A significant increase in PI incidence rate after THJE in patients with RA and JRA as compared to that in OA patients allows one to regard inflammatory RD as risk factors of this complication. The low effectiveness of the procedure for integrated therapy for PI in RD patients indicates that it needs to

  14. Study on biocompatibility, tribological property and wear debris characterization of ultra-low-wear polyethylene as artificial joint materials.

    Science.gov (United States)

    Bian, Yan-Yan; Zhou, Lei; Zhou, Gang; Jin, Zhong-Min; Xin, Shi-Xuan; Hua, Zi-Kai; Weng, Xi-Sheng

    2018-03-10

    Ultra-low-wear polyethylene (ULWPE) is a new type polyethylene made by experts who are from China petrochemical research institute, which is easy to process and implant. Preliminary test showed it was more resistant to wear than that of Ultra-high-molecular weight polyethylene (UHMWPE). The purpose of the research is to study biocompatibility, bio-tribological properties and debris characterization of ULWPE. Cytotoxicity test, hemolysis test, acute/chronic toxicity and muscular implantation test were conducted according to national standard GB/T-16886/ISO-10993 for evaluation requirements of medical surgical implants. We obtained that this novel material had good biocompatibility and biological safety. The wear performance of ULWPE and UHMWPE was evaluated in a pin-on-disc (POD) wear tester within two million cycles and a knee wear simulator within six million cycles. We found that the ULWPE was higher abrasion resistance than the UHMWPE, the wear rate of ULWPE by POD test and knee wear simulator was 0.4 mg/10 6 cycles and (16.9 ± 1.8)mg/10 6 cycles respectively, while that of UHMWPE was 1.8 mg/10 6 cycles and (24.6 ± 2.4)mg/10 6 cycles. The morphology of wear debris is also an important factor to evaluate artificial joint materials, this study showed that the ULWPE wear debris gotten from the simulator had various different shapes, including spherical, block, tear, etc. The morphology of worn surface and wear debris analysis showed that wear mechanisms of ULWPE were adhesion wear, abrasive wear and fatigue wear and other wear forms, which were consistent with that of UHMWPE. Thus we conclude that ULWPE is expected to be a lifetime implantation of artificial joint. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Total joint replacement: A multiple risk factor analysis of physical activity level 1-2 years postoperatively.

    Science.gov (United States)

    Paxton, Elizabeth W; Torres, Andy; Love, Rebecca M; Barber, Thomas C; Sheth, Dhiren S; Inacio, Maria C S

    2016-07-01

    Background and purpose - The effect of total joint arthroplasty (TJA) on physical activity is not fully understood. We investigated the change in physical activity after TJA and patient factors associated with change. Patients and methods - Using a total joint replacement registry, primary total hip arthroplasty (THA) patients (n = 5,678) and knee arthroplasty (TKA) patients (n = 11,084) between January 1, 2010 and December 31, 2012 were identified. Median age at THA was 68 and median age at TKA was 67. Change in self-reported physical activity (minutes per week) from before TJA (within 1 year of surgery) to after TJA (1-2 years) was the outcome of interest. Patient demographics and comorbidities were evaluated as risk factors. Multiple linear regression was used. Results - Median physical activity before surgery was 50 min/week (IQR: 0-140) for THA patients and 58 (IQR: 3-143) for TKA patients. Median physical activity after surgery was 150 min/week (IQR: 60-280) for both THA patients and TKA patients. Following TJA, 50% of patients met CDC/WHO physical activity guideline criteria. Higher body mass index was associated with lower change in physical activity (THA: -7.1 min/week; TKA: -5.9 min/week). Females had lower change than males (THA: -11 min/week; TKA: -9.1 min/week). In TKA patients, renal failure was associated with lower change (-17 min/week), as were neurological disorders (-30 min/week). Interpretation - Self-reported minutes of physical activity increased from before to after TJA, but 50% of TJA patients did not meet recommended physical activity guideline criteria. Higher body mass index, female sex, and specific comorbidities were found to be associated with low change in physical activity. Patient education on the benefits of physical activity should concentrate on these subgroups of patients.

  16. A Review of 399 Total Ankle Replacements: Analysis of Ipsilateral Subtalar Joint Arthrodesis and Associated Talar Component Subsidence.

    Science.gov (United States)

    Prissel, Mark A; Hyer, Christopher F; Berlet, Gregory C

    Total ankle replacement (TAR) is an accepted treatment for end-stage ankle arthritis. When concurrent subtalar joint pathologic features exist, ipsilateral subtalar joint arthrodesis (STJA) can be performed either simultaneous with TAR or as a staged procedure. Limited data exist on the effect of talar component subsidence and prosthesis survivorship. The present study purpose was to evaluate the effect of STJA on talar component subsidence after primary TAR and its effect on TAR survivorship. All patients, a minimum of 18 years old, from a single institution with modern-generation TAR and 1-year minimum follow-up data available were evaluated. The study group included patients who had also undergone STJA, and the control group (no STJA) was matched 1:1 by age, gender, and prosthesis. The initial postoperative weightbearing and most recent weightbearing radiographs were compared for talar component subsidence. We reviewed 399 primary TARs from 2004 to 2012. A total of 33 patients with ipsilateral STJA met the inclusion criteria and had an appropriate control group match. In the study group, 8 patients required a return to the operating room for 4 revisions and 4 reoperations at a median follow-up point of 24.3 months. Of the controls, 9 patients required a return to the operating room, with 4 revisions and 5 reoperations at a median follow-up point of 38.4 months. No statistically significant radiographic differences were found between the 2 groups. Primary TAR and ipsilateral STJA were infrequently required (41 of 399; 10.3%). TAR did not result in decreased survivorship when performed with ipsilateral STJA at an early follow-up point. Further study is warranted to determine any differences among previous, simultaneous, and subsequent STJA with ipsilateral TAR, and a matched longitudinal analysis is needed to determine longer term survivorship. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  17. Hospital Discharge Information After Elective Total hip or knee Joint Replacement Surgery: A clinical Audit of preferences among general practitioners

    Directory of Open Access Journals (Sweden)

    Andrew M Briggs

    2012-05-01

    Full Text Available AbstractThe demand for elective joint replacement (EJR surgery for degenerative joint disease continues to rise in Australia, and relative to earlier practices, patients are discharged back to the care of their general practitioner (GP and other community-based providers after a shorter hospital stay and potentially greater post-operative acuity. In order to coordinate safe and effective post-operative care, GPs rely on accurate, timely and clinically-informative information from hospitals when their patients are discharged. The aim of this project was to undertake an audit with GPs regarding their preferences about the components of information provided in discharge summaries for patients undergoing EJR surgery for the hip or knee. GPs in a defined catchment area were invited to respond to an online audit instrument, developed by an interdisciplinary group of clinicians with knowledge of orthopaedic surgery practices. The 15-item instrument required respondents to rank the importance of components of discharge information developed by the clinician working group, using a three-point rating scale. Fifty-three GPs and nine GP registrars responded to the audit invitation (11.0% response rate. All discharge information options were ranked as ‘essential’ by a proportion of respondents, ranging from 14.8–88.5%. Essential information requested by the respondents included early post-operative actions required by the GP, medications prescribed, post-operative complications encountered and noting of any allergies. Non-essential information related to the prosthesis used. The provision of clinical guidelines was largely rated as ‘useful’ information (47.5–56.7%. GPs require a range of clinical information to safely and effectively care for their patients after discharge from hospital for EJR surgery. Implementation of changes to processes used to create discharge summaries will require engagement and collaboration between clinical staff

  18. Multidisciplinary approach in the management of absolute trismus with bilateral temporomandibular joint replacements for a patient with juvenile idiopathic arthritis.

    Science.gov (United States)

    Fanaras, Nikolaos; Parry, Nicholas S; Matthews, N Shaun

    2014-11-01

    Juvenile idiopathic arthritis (JIA) is an exclusion diagnosis that gathers together all forms of arthritis that begin before the age of 16 years, persist for more than 6 weeks and are of unknown origin. We present the case of a 42 year old woman with a 20 year history of absolute trismus, secondary to bilateral temporomandibular joint (TMJ) ankylosis caused by JIA. The trismus resulted in grossly compromised oral hygiene and limited the patient to a semi-solid diet. JIA also affected her neck leading to a severe cervico-thoracic kyphosis. The patient who had been wheelchair bound developed severe lymphoedema of both lower limbs, complicating the pre-operative work up further. This particularly challenging case required input from specialists in anaesthetics, neurosurgery, special care dentistry, intensive care and maxillofacial surgery. Treatment consisted of ankylosis release, dental clearance and bilateral alloplastic replacement of her TMJs with custom implants. A full range of hinge movement and good functional outcome was achieved. This case presents the multidisciplinary approach to a severely compromised patient and illustrates the pre-, intra- and postoperative management of bilateral TMJ ankylosis with bespoke implants. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  19. Synovial fluid lubrication of artificial joints: protein film formation and composition.

    Science.gov (United States)

    Fan, Jingyun; Myant, Connor; Underwood, Richard; Cann, Philippa

    2012-01-01

    Despite design improvements, wear of artificial implants remains a serious health issue particularly for Metal-on-Metal (MoM) hips where the formation of metallic wear debris has been linked to adverse tissue response. Clearly it is important to understand the fundamental lubrication mechanisms which control the wear process. It is usually assumed that MoM hips operate in the ElastoHydrodynamic Lubrication (EHL) regime where film formation is governed by the bulk fluid viscosity; however there is little experimental evidence of this. The current paper critically examines synovial fluid lubrication mechanisms and the effect of synovial fluid chemistry. Two composition parameters were chosen; protein content and pH, both of which are known to change in diseased or post-operative synovial fluid. Film thickness and wear tests were carried out for a series of model synovial fluid solutions. Two distinct film formation mechanisms were identified; an adsorbed surface film and a high-viscosity gel. The entrainment of this gel controls film formation particularly at low speeds. However wear of the femoral head still occurs and this is thought to be due primarily to a tribo-corrosion mechanisms. The implications of this new lubrication mechanism and the effect of different synovial fluid chemistries are examined. One important conclusion is that patient synovial fluid chemistry plays an important role in determining implant wear and the likelihood of failure.

  20. Intrathoracic esophageal replacement in the dog with the use of an artificial esophagus composed of a collagen sponge with a double-layered silicone tube.

    Science.gov (United States)

    Yamamoto, Y; Nakamura, T; Shimizu, Y; Matsumoto, K; Takimoto, Y; Kiyotani, T; Sekine, T; Ueda, H; Liu, Y; Tamura, N

    1999-08-01

    Intrathoracic esophageal replacement with an artificial esophagus is considered difficult. We attempted to replace the intrathoracic esophagus with an artificial esophagus composed of a collagen sponge with a double-layered silicone tube and examined the state of host tissue regeneration. A 5-cm long gap was created in the intrathoracic esophagus in 9 dogs and repaired by interposition of our prosthesis. The dogs were fed only by intravenous hyperalimentation for 28 days. The silicone tube was removed at 29 days after the operation, and oral feeding was reintroduced. One dog was put to death at each of the following times: 1, 2, 3, 3, 6, 12, and 24 months after the operation. One dog is still surviving without problems after more than 26 months. One dog died of malnutrition at 10 months. In all dogs, the host regenerated tissue had replaced the resulting gap at the time of silicone tube removal. The mucosa had fully regenerated within 3 months and the glands within 12 months. The process of stenosis and shrinkage was complete within 3 months and did not advance thereafter. The lamina muscularis mucosae were observed as islets of smooth muscle within 12 months. Although the skeletal muscle regenerated close to the anastomoses, it did not extend to the middle of the regenerated esophagus even after 24 months. Use of a collagen sponge with a double-layered silicone tube was shown to be feasible even in the thorax and to allow the regenerated host tissue, consisting of the mucosa, glands, and lamina muscularis mucosae, to replace the esophageal gap.

  1. Formulation of reduced-calorie biscuits using artificial sweeteners and fat replacer with dairy–multigrain approach

    Directory of Open Access Journals (Sweden)

    Dipesh Aggarwal

    2016-03-01

    Conclusion: The study demonstrated that highly acceptable reduced-calorie biscuits can be produced by using dairy–multigrain composite flour with maltitol and FOS-sucralose (as sweetener and PD (as fat replacer.

  2. Grafting of poly(2-methacryloyloxyethyl phosphorylcholine) on polyethylene liner in artificial hip joints reduces production of wear particles.

    Science.gov (United States)

    Moro, Toru; Kyomoto, Masayuki; Ishihara, Kazuhiko; Saiga, Kenichi; Hashimoto, Masami; Tanaka, Sakae; Ito, Hideya; Tanaka, Takeyuki; Oshima, Hirofumi; Kawaguchi, Hiroshi; Takatori, Yoshio

    2014-03-01

    Despite improvements in the techniques, materials, and fixation of total hip arthroplasty, periprosthetic osteolysis, a complication that arises from this clinical procedure and causes aseptic loosening, is considered to be a major clinical problem associated with total hip arthroplasty. With the objective of reducing the production of wear particles and eliminating periprosthetic osteolysis, we prepared a novel hip polyethylene (PE) liner whose surface graft was made of a biocompatible phospholipid polymer-poly(2-methacryloyloxyethyl phosphorylcholine (MPC)). This study investigated the wear resistance of the poly(MPC)-grafted cross-linked PE (CLPE; MPC-CLPE) liner during 15×10(6) cycles of loading in a hip joint simulator. The gravimetric analysis showed that the wear of the acetabular liner was dramatically suppressed in the MPC-CLPE liner, as compared to that in the non-treated CLPE liner. Analyses of the MPC-CLPE liner surface revealed that it suffered from no or very little wear even after the simulator test, whereas the CLPE liners suffered from substantial wears. The scanning electron microscope (SEM) analysis of the wear particles isolated from the lubricants showed that poly(MPC) grafting dramatically decreased the total number, area, and volume of the wear particles. However, there was no significant difference in the particle size distributions, and, in particular, from the SEM image, it was observed that particles with diameters less than 0.50μm were present in the range of the highest frequency. In addition, there were no significant differences in the particle size descriptors and particle shape descriptors. The results obtained in this study show that poly(MPC) grafting markedly reduces the production of wear particles from CLPE liners, without affecting the size of the particles. These results suggest that poly(MPC) grafting is a promising technique for increasing the longevity of artificial hip joints. Copyright © 2013 Elsevier Ltd. All rights

  3. Thermomechanical behavior of virgin and highly crosslinked ultra-high molecular weight polyethylene used in total joint replacements.

    Science.gov (United States)

    Kurtz, S M; Villarraga, M L; Herr, M P; Bergström, J S; Rimnac, C M; Edidin, A A

    2002-09-01

    predicting the thermomechanical behavior of conventional and crosslinked UHMWPE used in total joint replacements.

  4. FIVE YEAR OUTCOMES OF CERAMIC-ОN-CERAMIC AND CERAMIC-ОN-POLYETHYLENE BEARINGS IN HIP JOINT REPLACEMENT

    Directory of Open Access Journals (Sweden)

    V. Yu. Murylev

    2017-01-01

    Full Text Available In view of the increasing number of hip joint replacement volume there remains the key issue of improving prosthesis survivorship which directly depends on the friction couple. Material and methods. The authors have analyzed five year outcomes of two bearing types (head and insert used in hip replacement: ceramic-on-ceramic (CoC in 324 patients and ceramic-on-polyethylene (CoP in 300 patients. Totally 550 patients were operated in the period starting 2010 till 2014, including 74 patients underwent bilateral hip replacement. The authors divided patients based on gender and also into three age groups: 20-40, 41-60 and 61-80 years old. The largest group comprised 156 women aged 41-60 years (28.4%. Additional grouping of patients was made based on gender, age and bearing diameter.36 mm diameter bearing was characterized of the most frequent use. Functional outcomes were assessed by Harris Hip Score. Statistical analysis was made with Statistica 10 software. Statistical significant was observed at p<0.05.Results.28 mm diameter bearing were rarely (19.5% applied and mainly in women which is related to need for use of smaller acetabulum components and inability to implant a larger insert.36 mm diameter bearing were used most frequently, CoC articulation of36 mm was used in men in 34% of cases and in women – in 18.12% of cases.40 mm articulations were implanted in women two times less than in men which is related to a smaller diameter of acetabulum in women. Generally, CoC bearings were implanted more often in men which can be explained by a bigger social demand as well as a higher anti-luxation stability of large diameter bearings. Dislocations of implants occurred in 5 (0.91% patients: in 4 patients with CoP bearingand in one patient with CoC articulation. Four revision procedures (0.64% were made due to deep periprosthetic infection: two surgeries in each group. Harris Hip Score evaluation in CoC group demonstrated excellent and good outcomes in

  5. Biochemical and histological evaluation of the synovial-like tissue around failed (loose) total joint replacement prostheses in human subjects and a canine model.

    Science.gov (United States)

    Thornhill, T S; Ozuna, R M; Shortkroff, S; Keller, K; Sledge, C B; Spector, M

    1990-07-01

    The tissue around loose total joint replacement prostheses displays a synovial-like lining comprised of cells that produce IL-1 and PGE2, mediators of inflammation that stimulate bone resorption. Particles of titanium alloy, as well as cobalt-chromium alloy and polyethylene, were found to aggravate the histiocytic response and production of IL-1 and PGE2. Tissue with similar histological and biochemical features was produced in a canine model of the aseptic loose cemented femoral stem.

  6. The Discover artificial disc replacement versus fusion in cervical radiculopathy--a randomized controlled outcome trial with 2-year follow-up.

    Science.gov (United States)

    Skeppholm, Martin; Lindgren, Lars; Henriques, Thomas; Vavruch, Ludek; Löfgren, Håkan; Olerud, Claes

    2015-06-01

    Several previous studies comparing artificial disc replacement (ADR) and fusion have been conducted with cautiously positive results in favor of ADR. This study is not, in contrast to most previous studies, an investigational device exemption study required by the Food and Drug Administration for approval to market the product in the United States. This study was partially funded with unrestricted institutional research grants by the company marketing the artificial disc used in this study. To compare outcomes between the concepts of an artificial disc to treatment with anterior cervical decompression and fusion (ACDF) and to register complications associated to the two treatments during a follow-up time of 2 years. This is a randomized controlled multicenter trial, including three spine centers in Sweden. The study included patients seeking care for cervical radiculopathy who fulfilled inclusion criteria. In total, 153 patients were included. Self-assessment with Neck Disability Index (NDI) as a primary outcome variable and EQ-5D and visual analog scale as secondary outcome variables. Patients were randomly allocated to either treatment with the Depuy Discover artificial disc or fusion with iliac crest bone graft and plating. Randomization was blinded to both patient and caregivers until time for implantation. Adverse events, complications, and revision surgery were registered as well as loss of follow-up. Data were available in 137 (91%) of the included and initially treated patients. Both groups improved significantly after surgery. NDI changed from 63.1 to 39.8 in an intention-to-treat analysis. No statistically significant difference between the ADR and the ACDF groups could be demonstrated with NDI values of 39.1 and 40.1, respectively. Nor in secondary outcome measures (EQ-5D and visual analog scale) could any statistically significant differences be demonstrated between the groups. Nine patients in the ADR group and three in the fusion group underwent

  7. Edward Rhodes Stitt Award Lecture. Will a computer (with artificial vision) replace the surgical pathologist (or other health professionals)?

    Science.gov (United States)

    Heffner, D K

    1994-04-01

    Many jobs require vision for most of the tasks performed and the discussion focuses on the nature of human visual perception. Arguments are given to support the claim that visual perception is a very complicated function of the brain. To attempt to answer whether or not artificial intelligence (AI) will ever be able to essentially do what the brain does, the history and current state of AI research is examined, with special attention to neural net research.

  8. Comparison of radiographic joint space width and magnetic resonance imaging for prediction of knee replacement: A longitudinal case-control study from the Osteoarthritis Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Eckstein, Felix; Wirth, Wolfgang; Cotofana, Sebastian [Paracelsus Medical University Salzburg and Nuremberg Austria and Chondrometrics GmbH, Institute of Anatomy, Ainring (Germany); Boudreau, Robert [University of Pittsburgh, Department of Epidemiology, Graduate School of Public Health, Pittsburgh, PA (United States); Wang, Zhijie; Hannon, Michael J. [University of Pittsburgh and Pittsburgh VAHS, Division of Rheumatology and Clinical Immunology, Pittsburgh, PA (United States); Duryea, Jeff [Brigham and Women' s Hospital, Harvard Medical School, Boston, MA (United States); Guermazi, Ali [Boston University School of Medicine and Boston Imaging Core Lab (BICL), LLC, Boston, MA (United States); Roemer, Frank [Boston University School of Medicine and Boston Imaging Core Lab (BICL), LLC, Boston, MA (United States); University of Erlangen-Nuremberg, Department of Radiology, Erlangen (Germany); Nevitt, Michael [OAI Coordinating Ctr., UCSF, San Francisco, CA (United States); John, Markus R. [Novartis Pharma AG, Basel (Switzerland); Ladel, Christoph [Merck KGaA, Darmstadt (Germany); Sharma, Leena [Northwestern University, Department of Medicine, Feinberg School of Medicine, Chicago, IL (United States); Hunter, David J. [University Sydney, Royal North Shore Hospital and Institute of Bone and Joint Research, Kolling Institute, Sydney, NSW (Australia); Kwoh, C.K. [University of Arizona, Division of Rheumatology and the University of Arizona Arthritis Center, Tucson, AZ (United States); Collaboration: OAI Investigators

    2016-06-15

    To evaluate whether change in fixed-location measures of radiographic joint space width (JSW) and cartilage thickness by MRI predict knee replacement. Knees replaced between 36 and 60 months' follow-up in the Osteoarthritis Initiative were each matched with one control by age, sex and radiographic status. Radiographic JSW was determined from fixed flexion radiographs and subregional femorotibial cartilage thickness from 3 T MRI. Changes between the annual visit before replacement (T{sub 0}) and 2 years before T{sub 0} (T{sub -2}) were compared using conditional logistic regression. One hundred and nineteen knees from 102 participants (55.5 % women; age 64.2 ± 8.7 [mean ± SD] years) were studied. Fixed-location JSW change at 22.5 % from medial to lateral differed more between replaced and control knees (case-control [cc] OR = 1.57; 95 % CI: 1.23-2.01) than minimum medial JSW change (ccOR = 1.38; 95 % CI: 1.11-1.71). Medial femorotibial cartilage loss displayed discrimination similar to minimum JSW, and central tibial cartilage loss similar to fixed-location JSW. Location-independent thinning and thickening scores were elevated prior to knee replacement. Discrimination of structural progression between knee pre-placement cases versus controls was stronger for fixed-location than minimum radiographic JSW. MRI displayed similar discrimination to radiography and suggested greater simultaneous cartilage thickening and loss prior to knee replacement. (orig.)

  9. Artificial Lighting Protection of Mauna Kea Observatories: An Experiment to Replace LPS Street Lighting With LEDs in Waikoloa Village, HI

    Science.gov (United States)

    Craine, Eric R.; Craine, Brian L.

    2016-06-01

    Segments of the astronomical community have long lobbied in support of the use of Low Pressure Sodium (LPS) street lights as a method of minimizing impacts of sky glow on neighboring observatories. There has been vociferous objection to the replacement of LPS by Light Emitting Diode (LED) street lights. Such replacement is being precipitated by advances in lighting technologies, high economic efficiencies of LEDs, and plummeting interest in manufacturing LPS fixtures. Waikoloa Village, HI, located on the western slopes of Mauna Kea, home to major northern hemisphere observatories, has for many years been almost exclusively illuminated by LPS lighting. During the winter of 2015-2016 the County of Hawai’i Department of Public Works, Traffic Division replaced the approximately 550 LPS street lights in the community with Filtered LED (FLED) fixtures on a one-for-one basis. About 100 other LPS lights on private properties in the community were similarly replaced by the lighting manufacturer. This retrofit offered an excellent opportunity to make measurements of lighting parameters in the community before and after the retrofit process. Measurements were made using satellite, airborne, and ground based observations, and included photometric, photographic, and spectroscopic measurements. Data analyzed included integrated brightness of the community, zenith angle function brightness distributions, and spectral energy distributions. We present the results of these observations and discuss their implications for future protection of astronomical observatory sites.

  10. [Clinical analysis of prosthesis replacement for proximal humerus tumors].

    Science.gov (United States)

    Weng, Xiaojun; Liao, Qiande; Li, Xiaosheng; Wang, Jing

    2016-01-01

    To explore surgical strategies, functions and prognosis of artificial prosthesis replacement and soft tissue reconstruction for patients with invasive benign or primary malignant proximal humerus tumor.
 A total of 17 patients with invasive benign or primary malignant proximal humerus tumor underwent prosthetic replacement after segment bone tumor resection and soft tissues reconstruction from April 2007 to April 2014 were enrolled. Based on histological types, tumor stages and surgical procedures, the effects of artificial prosthesis replacement and soft tissue reconstruction on prognosis and shoulder joint function were evaluated.
 All patients were followed up for 8 to 96 months (average time: 58.9 months). Among 11 patients with primary malignant tumor, 5 died of tumor recurrence or metastasis, and 6 showed tumor-free survival for 24 to 91 months (average time: 54.83 months). The 6 patients with aggressive benign tumors survived for 39 to 96 months, with an average of 72.33 months. The shoulder joint function of 17 patients recovered to 64.88% of normal. There were significant differences in the shoulder joint function between the patients who underwent half shoulder replacement and those who underwent total shoulder replacement (56.25% vs 72.56%, Pshoulder joint function between the patients who underwent Type I A excision (retention of abductor muscles and rotator cuff) and those who underwent Type I B excision (68.75% vs 61.44%, Pshoulder joint function is associated with the methods of prosthesis replacement and soft tissue resection.

  11. Feasibility of establishing an Australian ACL registry: a pilot study by the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR).

    Science.gov (United States)

    Lekkas, Christina; Clarnette, Richard; Graves, Stephen E; Rainbird, Sophia; Parker, David; Lorimer, Michelle; Paterson, Roger; Roe, Justin; Morris, Hayden; Feller, Julian A; Annear, Peter; Forster, Ben; Hayes, David

    2017-05-01

    Rupture of the anterior cruciate ligament (ACL) is a common and debilitating injury that impacts significantly on knee function and risks the development of degenerative arthritis. The outcome of ACL surgery is not monitored in Australia. The optimal treatment is unknown. Consequently, the identification of best practice in treating ACL is crucial to the development of improved outcomes. The Australian Knee Society (AKS) asked the Australian Orthopaedic Association (AOA) to consider establishing a national ACL registry. As a first step, a pilot study was undertaken by the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) to test the hypothesis that collecting the required information in the Australian setting was possible. Surgeons completed an operative form which provided comprehensive information on the surgery undertaken. Patients provided pre- and post-operative questionnaires including the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Marx Activity Scale (MA Scale). The number of ACL procedures undertaken at each hospital during the recruitment period was compared against State Government Health Department separation data. A total of 802 patients were recruited from October 2011 to January 2013. The overall capture rate for surgeon-derived data was 99%, and the capture rate for the pre-operative patient questionnaire was 97.9%. At 6 months, patient-reported outcomes were obtained from 55% of patients, and 58.5% of patients at 12 months. When checked against State Government Health Department separation data, 31.3% of procedures undertaken at each study hospital were captured in the study. It is possible to collect surgeon-derived and pre-operative patient-reported data, following ACL reconstruction in Australia. The need to gain patient consent was a limiting factor to participation. When patients did consent to participate in the study, we were able to capture nearly 100% of surgical procedures. Patient consent

  12. Use of a GIS-based hybrid artificial neural network to prioritize the order of pipe replacement in a water distribution network.

    Science.gov (United States)

    Ho, Cheng-I; Lin, Min-Der; Lo, Shang-Lien

    2010-07-01

    A methodology based on the integration of a seismic-based artificial neural network (ANN) model and a geographic information system (GIS) to assess water leakage and to prioritize pipeline replacement is developed in this work. Qualified pipeline break-event data derived from the Taiwan Water Corporation Pipeline Leakage Repair Management System were analyzed. "Pipe diameter," "pipe material," and "the number of magnitude-3( + ) earthquakes" were employed as the input factors of ANN, while "the number of monthly breaks" was used for the prediction output. This study is the first attempt to manipulate earthquake data in the break-event ANN prediction model. Spatial distribution of the pipeline break-event data was analyzed and visualized by GIS. Through this, the users can swiftly figure out the hotspots of the leakage areas. A northeastern township in Taiwan, frequently affected by earthquakes, is chosen as the case study. Compared to the traditional processes for determining the priorities of pipeline replacement, the methodology developed is more effective and efficient. Likewise, the methodology can overcome the difficulty of prioritizing pipeline replacement even in situations where the break-event records are unavailable.

  13. The association between C-reactive protein and the likelihood of progression to joint replacement in people with rheumatoid arthritis: a retrospective observational study

    Directory of Open Access Journals (Sweden)

    Reynolds Alan

    2008-11-01

    Full Text Available Abstract Background This study sought to evaluate the association between systemic inflammation as measured by C-reactive protein and total joint replacement and the association between change in CRP status (low, ≤ 10 mg/L and high, >10 mg/L measured over one year and total joint replacement in patients diagnosed with rheumatoid arthritis. Methods A cohort of patients was selected from The Health Improvement Network (THIN dataset of anonymised patient-level data from UK general practice with a confirmed chronic rheumatic diagnosis. Surgery-free survival was evaluated using Cox proportional hazards regression models (CPHM. Results 2,421 cases had at least one CRP measurement of which 125 cases (5.2% had at least one major joint replacement. In CPHM, each additional unit increase in log mean CRP (range 1 to 6 was associated with a hazard ratio (HR for major orthopaedic surgery of 1.36 (95% CI 1.10 to 1.67; p = 0.004, after controlling for age at first rheumatoid presentation and average body mass index over the same observation period. Repeated CRP observations around one year apart were recorded in 1,314 subjects. After controlling for confounding factors, in cases whose CRP remained high (>10 mg/L, the HR for joint replacement increased more than two-fold (p = 0.040 relative to cases whose CRP remained low. In patients whose CRP increased from low to high, the HR was 1.86 compared to those who remained in a low state (p = 0.217. By comparison, among those subjects whose CRP was reduced from a high to low state, the hazard ratio was more than halved (1.46 from to those who remained high (p = 0.441. Although underpowered, the trend evident from CRP change corroborates the association of TJR progression with mean CRP. Conclusion CRP level predicts progression to major joint replacement after standardisation for relevant risk factors as did change in CRP status between low and high states observed over one year.

  14. Dose-dependent cytotoxicity evaluation of graphite nanoparticles for diamond-like carbon film application on artificial joints.

    Science.gov (United States)

    Liao, T T; Deng, Q Y; Wu, B J; Li, S S; Li, X; Wu, J; Leng, Y X; Guo, Y B; Huang, N

    2017-01-24

    While a diamond-like carbon (DLC)-coated joint prosthesis represents the implant of choice for total hip replacement in patients, it also leads to concern due to the cytotoxicity of wear debris in the form of graphite nanoparticles (GNs), ultimately limiting its clinical use. In this study, the cytotoxicity of various GN doses was evaluated. Mouse macrophages and osteoblasts were incubated with GNs (cytotoxicity by means of assessing inflammatory cytokines, results of alkaline phosphatase assays, and related signaling protein expression. Cytotoxicity evaluation showed that cell viability decreased in a dose-dependent manner (10-100 μg ml -1 ), and steeply declined at GNs concentrations greater than 30 μg ml -1 . Noticeable cytotoxicity was observed as the GN dose exceeded this threshold due to upregulated receptor of activator of nuclear factor kB-ligand expression and downregulated osteoprotegerin expression. Meanwhile, activated macrophage morphology was observed as a result of the intense inflammatory response caused by the high doses of GNs (>30 μg ml -1 ), as observed by the increased release of TNF-α and IL-6. The results suggest that GNs had a significant dose-dependent cytotoxicity in vitro, with a lethal dose of 30 μg ml -1 leading to dramatic increases in cytotoxicity. Our GN cytotoxicity evaluation indicates a safe level for wear debris-related arthropathy and could propel the clinical application of DLC-coated total hip prostheses.

  15. The effect of sliding velocity on the mechanical response of an artificial joint in Topopah Spring Member tuff; Yucca Mountain Site Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, W.A.

    1994-04-01

    A smooth artificial joint in Topopah Spring Member tuff was sheared at constant normal stress at velocities from 0 to 100 {mu}m/s to determine the velocity-dependence of shear strength. Two different initial conditions were used: (1) unprimed -- the joint had been shear stress-free since last application of normal stress, and before renewed shear loading; and (2) primed -- the joint had undergone a slip history after application of normal stress, but before the current shear loading. Observed steady-state rate effects were found to be about 3 times lager than for some other silicate rocks. These different initial conditions affected the character of the stress-slip curve immediately after the onset of slip. Priming the joint causes a peak in the stress-slip response followed by a transient decay to the steady-state stress, i.e., slip weakening. Slide-hold-slide tests exhibit time-dependent strengthening. When the joint was subjected to constant shear stress, no slip was observed; that is, joint creep did not occur. One set of rate data was collected from a surface submerged in tap water, the friction was higher for this surface, but the rate sensitivity was the same as that for surfaces tested in the air-dry condition.

  16. Human bones obtained from routine joint replacement surgery as a tool for studies of plutonium, americium and {sup 90}Sr body-burden in general public

    Energy Technology Data Exchange (ETDEWEB)

    Mietelski, Jerzy W., E-mail: jerzy.mietelski@ifj.edu.pl [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Cracow (Poland); Golec, Edward B. [Traumatology and Orthopaedic Clinic, 5th Military Clinical Hospital and Polyclinic, Independent Public Healthcare Facility, Wroclawska 1-3, 30-901 Cracow (Poland); Orthopaedic Rehabilitation Department, Chair of Clinical Rehabilitation, Faculty of Motor of the Bronislaw Czech' s Academy of Physical Education, Cracow (Poland); Department of Physical Therapy Basics, Faculty of Physical Therapy, Administration College, Bielsko-Biala (Poland); Tomankiewicz, Ewa [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Cracow (Poland); Golec, Joanna [Orthopaedic Rehabilitation Department, Chair of Clinical Rehabilitation, Faculty of Motor of the Bronislaw Czech' s Academy of Physical Education, Cracow (Poland); Physical Therapy Department, Institute of Physical Therapy, Faculty of Heath Science, Jagiellonian University, Medical College, Cracow (Poland); Nowak, Sebastian [Traumatology and Orthopaedic Clinic, 5th Military Clinical Hospital and Polyclinic, Independent Public Healthcare Facility, Wroclawska 1-3, 30-901 Cracow (Poland); Orthopaedic Rehabilitation Department, Chair of Clinical Rehabilitation, Faculty of Motor of the Bronislaw Czech' s Academy of Physical Education, Cracow (Poland); Szczygiel, Elzbieta [Physical Therapy Department, Institute of Physical Therapy, Faculty of Heath Science, Jagiellonian University, Medical College, Cracow (Poland); Brudecki, Kamil [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Cracow (Poland)

    2011-06-15

    The paper presents a new sampling method for studying in-body radioactive contamination by bone-seeking radionuclides such as {sup 90}Sr, {sup 239+240}Pu, {sup 238}Pu, {sup 241}Am and selected gamma-emitters, in human bones. The presented results were obtained for samples retrieved from routine surgeries, namely knee or hip joints replacements with implants, performed on individuals from Southern Poland. This allowed to collect representative sets of general public samples. The applied analytical radiochemical procedure for bone matrix is described in details. Due to low concentrations of {sup 238}Pu the ratio of Pu isotopes which might be used for Pu source identification is obtained only as upper limits other then global fallout (for example Chernobyl) origin of Pu. Calculated concentrations of radioisotopes are comparable to the existing data from post-mortem studies on human bones retrieved from autopsy or exhumations. Human bones removed during knee or hip joint surgery provide a simple and ethical way for obtaining samples for plutonium, americium and {sup 90}Sr in-body contamination studies in general public. - Highlights: > Surgery for joint replacement as novel sampling method for studying in-body radioactive contamination. > Proposed way of sampling is not causing ethic doubts. > It is a convenient way of collecting human bone samples from global population. > The applied analytical radiochemical procedure for bone matrix is described in details. > The opposite patient age correlations trends were found for 90Sr (negative) and Pu, Am (positive).

  17. Exploring the relationships between International Classification of Functioning, Disability and Health (ICF) constructs of Impairment, Activity Limitation and Participation Restriction in people with osteoarthritis prior to joint replacement.

    Science.gov (United States)

    Pollard, Beth; Johnston, Marie; Dieppe, Paul

    2011-05-16

    The International Classification of Functioning, Disability and Health (ICF) proposes three main constructs, impairment (I), activity limitation (A) and participation restriction (P). The ICF model allows for all paths between the constructs to be explored, with significant paths likely to vary for different conditions. The relationships between I, A and P have been explored in some conditions but not previously in people with osteoarthritis prior to joint replacement. The aim of this paper is to examine these relationships using separate measures of each construct and structural equation modelling. A geographical cohort of 413 patients with osteoarthritis about to undergo hip and knee joint replacement completed the Aberdeen measures of Impairment, Activity Limitation and Participation Restriction (Ab-IAP). Confirmatory factor analysis was used to test the three factor (I, A, P) measurement model. Structural equation modelling was used to explore the I, A and P pathways in the ICF model. There was support from confirmatory factor analysis for the three factor I, A, P measurement model. The structural equation model had good fit [S-B Chi-square = 439.45, df = 149, CFI robust = 0.91, RMSEA robust = 0.07] and indicated significant pathways between I and A (standardised coefficient = 0.76 p < 0.0001) and between A and P (standardised coefficient = 0.75 p < 0.0001). However, the path between I and P was not significant (standardised coefficient = 0.01). The significant pathways suggest that treatments and interventions aimed at reducing impairment, such as joint replacement, may only affect P indirectly, through A, however, longitudinal data would be needed to establish this.

  18. A comparison of the clinical and experimental characteristics of four acute surgical pain models: dental extraction, bunionectomy, joint replacement, and soft tissue surgery.

    Science.gov (United States)

    Singla, Neil K; Desjardins, Paul J; Chang, Phoebe D

    2014-03-01

    When a clinical trial of an analgesic produces a negative finding, it is important to consider the influence (if any) of experimental error on the validity of that result. Although efforts to identify and minimize experimental error in chronic pain investigations have begun in earnest, less work has been performed on the optimization of acute pain methodology. Of the acute surgical pain methodology articles that have been published over the last decade, almost all focus on either the dental or bunion model. Analgesics are typically evaluated in a variety of surgical models that eventually include hospital-based models (eg, joint replacement and soft tissue surgery). Every surgical procedure has unique clinical characteristics that must be considered to optimize study design and conduct. Much of the methodological knowledge garnered from bunion and dental studies is applicable to other surgical models, but some extrapolations are hazardous. The purposes of this review were (1) to qualitatively describe the clinical and experimental characteristics of the 4 classic surgical models: dental extraction, bunionectomy, joint replacement, and soft tissue surgery; and (2) to quantitatively compare the models by analyzing 3 factors: effect size, enrollment rate, and demographics. We found that the dental extraction and bunionectomy models had higher assay sensitivity than the joint replacement and soft tissue surgery models. It is probable that this finding is secondary to the superior experimental conditions under which the dental and bunion models are executed (utilization of few centers that have the ability to reduce surgical, anesthetic, and postoperative confounders). Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  19. Metabolic Effects of Replacing Sugar-Sweetened Beverages with Artificially-Sweetened Beverages in Overweight Subjects with or without Hepatic Steatosis: A Randomized Control Clinical Trial.

    Science.gov (United States)

    Campos, Vanessa; Despland, Camille; Brandejsky, Vaclav; Kreis, Roland; Schneiter, Philippe; Boesch, Chris; Tappy, Luc

    2017-02-27

    Addition of fructose to the diet of normal weight and overweight subjects can increase postprandial plasma triglyceride and uric acid concentration. We, therefore, assessed whether replacing sugar-sweetened beverages (SSB) with artificially-sweetened beverages (ASB) in the diet of overweight and obese subjects would decrease these parameters. Twenty-six participants of the REDUCS study, which assessed the effects of replacing SSB by ASB over 12 weeks on intra-hepatocellular lipid concentration, were included in this sub-analysis. All were studied after a four-week run-in period during which they consumed their usual diet and SSBs, and after a 12-week intervention in which they were randomly assigned to replace their SSBs with ASBs (ASB arm) or to continue their usual diet and SSBs (control arm, CTRL). At the end of run-in (week 4) and again at the end of intervention (week 16), they took part in an 8.5 h metabolic investigation during which their plasma glucose, insulin, glucagon, lactate, triglyceride (TG), non-esterified fatty acids (NEFA), and uric acid concentrations were measured over a 30 min fasting period (-30-0 min), then every 2 h over 480 min. with ingestion of standard breakfast at time 0 min and a standard lunch at time 240 min. Breakfast and lunch were consumed together with a 3.3 dL SSB at week 4 and with either an ASB (ASB arm) or a SSB (CTRL arm) at week 16. After analyzing the whole group, a secondary analysis was performed on 14 subjects with hepatic steatosis (seven randomized to ASB, seven to CTRL) and 12 subjects without hepatic steatosis (six randomized to ASB and six to CTRL). Ingestion of meals increased plasma glucose, insulin, glucagon, lactate, and TG concentrations and decreased NEFA concentrations, but with no significant difference of integrated postprandial responses between week 4 and week 16 in both ASB and CTRL, except for a slightly decreased glucagon response in ASB. There was, however, no significant postprandial increase in

  20. Metabolic Effects of Replacing Sugar-Sweetened Beverages with Artificially-Sweetened Beverages in Overweight Subjects with or without Hepatic Steatosis: A Randomized Control Clinical Trial

    Directory of Open Access Journals (Sweden)

    Vanessa Campos

    2017-02-01

    Full Text Available Objective: Addition of fructose to the diet of normal weight and overweight subjects can increase postprandial plasma triglyceride and uric acid concentration. We, therefore, assessed whether replacing sugar-sweetened beverages (SSB with artificially-sweetened beverages (ASB in the diet of overweight and obese subjects would decrease these parameters. Methods: Twenty-six participants of the REDUCS study, which assessed the effects of replacing SSB by ASB over 12 weeks on intra-hepatocellular lipid concentration, were included in this sub-analysis. All were studied after a four-week run-in period during which they consumed their usual diet and SSBs, and after a 12-week intervention in which they were randomly assigned to replace their SSBs with ASBs (ASB arm or to continue their usual diet and SSBs (control arm, CTRL. At the end of run-in (week 4 and again at the end of intervention (week 16, they took part in an 8.5 h metabolic investigation during which their plasma glucose, insulin, glucagon, lactate, triglyceride (TG, non-esterified fatty acids (NEFA, and uric acid concentrations were measured over a 30 min fasting period (−30–0 min, then every 2 h over 480 min. with ingestion of standard breakfast at time 0 min and a standard lunch at time 240 min. Breakfast and lunch were consumed together with a 3.3 dL SSB at week 4 and with either an ASB (ASB arm or a SSB (CTRL arm at week 16. After analyzing the whole group, a secondary analysis was performed on 14 subjects with hepatic steatosis (seven randomized to ASB, seven to CTRL and 12 subjects without hepatic steatosis (six randomized to ASB and six to CTRL. Results: Ingestion of meals increased plasma glucose, insulin, glucagon, lactate, and TG concentrations and decreased NEFA concentrations, but with no significant difference of integrated postprandial responses between week 4 and week 16 in both ASB and CTRL, except for a slightly decreased glucagon response in ASB. There was, however, no

  1. 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

  2. Major joint replacement. A model for antithrombotic drug development: from proof-of-concept to clinical use

    NARCIS (Netherlands)

    Dahl, O. E.; Borris, L. C.; Bergqvist, D.; Schnack Rasmussen, M.; Eriksson, B. I.; Kakkar, A. K.; Colwell, C. W.; Caprini, J. A.; Fletcher, J.; Friedman, R. J.; Lassen, M. R.; Frostick, S. P.; Sakon, M.; Kwong, L. M.; Kakkar, V. V.; Paiment, G. D.; Willie-Jørgensen, P.; Wakefield, T.; Cushner, F.; Fujita, S.; Mouret, P.; Ramacciotti, E.; Gomes, M.; Marotti, M.; Ogren, M.; Abe, Y.; Parakh, R.; Sylvest, A.; Velpeau, C.; Hamersley, S. L.; van Dijk, C. N.; Arcelus, J. I.; Akagi, M.; Planes, A.; Fisher, W. D.; de A Maffei, F. H.; Westrich, G. H.; Jawien, A.; Wang, C. J.; Ryge, C.; Skinner, J.; Waddell, J. P.; Greer, I. A.; Wenzi, M. E.; Jacobson, B. F.; Kurtoglu, M. H.

    2008-01-01

    AIM: Development of antithrombotic compounds has traditionally been performed in patients undergoing total hip and knee replacement surgery. A high number of asymptomatic deep-vein thromboses are radiologically detectable, and bleeding and other adverse events (AE) are easy to observe. However,

  3. Investigation of silicon carbon nitride nanocomposite films as a wear resistant layer in vitro and in vivo for joint replacement applications.

    Science.gov (United States)

    Liang, Y; Liu, D G; Bai, W Q; Tu, J P

    2017-05-01

    Silicon-contained CN x nanocomposite films were prepared using the ion beam assisted magnetron sputtering under different nitrogen gas pressure. With increase of the nitrogen pressure, silicon and nitrogen content of the CN x films drastically increase, and is saturated as the P N2 reach about 40%. Surface roughness and the contact angle are increase, while the friction coefficient decreased. The CN x film with 5.7at.% Si content possess the lowest friction coefficient of only 0.07, and exhibited the best tribological properties. The impact of CN x films with different silicon content on the growth and the activation of osteoblasts were compared to that of Ti6Al4V. The incorporation of silicon in the CN x film also showed an increase cell adhesion. Bonding structure and surface energy were determined to be the factors contributing to the improved biocompatibility. Macrophages attached to 5.7at.% Si contained CN x films down regulated their production of cytokines and chemokines. Moreover, employed with Si contained CN x coated joint replacements, which were implanted subcutaneously into Sprague-Dawley mice for up to 36days, the tissue reaction and capsule formation was significantly decreased compared to that of Ti6Al4V. A mouse implantation study demonstrated the excellent in vivo biocompatibility and functional reliability of wear resist layer for joint replacements with a Si doped a-CN x coating for 36days. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Enhanced lubricant film formation through micro-dimpled hard-on-hard artificial hip joint: An in-situ observation of dimple shape effects.

    Science.gov (United States)

    Choudhury, Dipankar; Rebenda, David; Sasaki, Shinya; Hekrle, Pavel; Vrbka, Martin; Zou, Min

    2018-02-17

    This study evaluates the impact of dimple shapes on lubricant film formation in artificial hip joints. Micro-dimples with 20-50 µm lateral size and 1 ± 0.2 µm depths were fabricated on CrCoMo hip joint femoral heads using a picosecond laser. Tribological studies were performed using a pendulum hip joint simulator to apply continuous swing flexion-extension motions. The results revealed a significantly enhanced lubricant film thickness (≥ 500 nm) with micro-dimpled prosthesis heads at equilibrium position after the lubricant film has fully developed. The average lubricant film thickness of dimpled prostheses with square- and triangular-shaped dimple arrays over time is about 3.5 that of the non-dimpled prosthesis (204 nm). Remarkably, the prosthesis with square-shaped dimple arrays showed a very fast lubricant film formation reaching their peak values within 0.5 s of pendulum movement, followed by prosthesis with triangular-shaped dimple arrays with a transition period of 42.4 s. The fully developed lubricant film thicknesses (≥ 700 nm) are significantly higher than the surface roughness (≈ 25 nm) demonstrating a hydrodynamic lubrication. Hardly any scratches appeared on the post-experimental prosthesis with square-shaped dimple array and only a few scratches were found on the post-experimental prosthesis with triangular-shaped dimple arrays. Thus, prostheses with square-shaped dimple arrays could be a potential solution for durable artificial hip joints. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. A comparison of discharge functional status after rehabilitation in skilled nursing, home health, and medical rehabilitation settings for patients after lower-extremity joint replacement surgery.

    Science.gov (United States)

    Mallinson, Trudy R; Bateman, Jillian; Tseng, Hsiang-Yi; Manheim, Larry; Almagor, Orit; Deutsch, Anne; Heinemann, Allen W

    2011-05-01

    To examine differences in outcomes of patients after lower-extremity joint replacement across 3 post-acute care (PAC) rehabilitation settings. Prospective observational cohort study. Skilled nursing facilities (SNFs; n=5), inpatient rehabilitation facilities (IRFs; n=4), and home health agencies (HHAs; n=6) from 11 states. Patients with total knee (n=146) or total hip replacement (n=84) not related to traumatic injury. None. Self-care and mobility status at PAC discharge measured by using the Inpatient Rehabilitation Facility Patient Assessment Instrument. Based on our study sample, HHA patients were significantly less dependent than SNF and IRF patients at admission and discharge in self-care and mobility. IRF and SNF patients had similar mobility levels at admission and discharge and similar self-care at admission, but SNF patients were more independent in self-care at discharge. After controlling for differences in patient severity and length of stay in multivariate analyses, HHA setting was not a significant predictor of self-care discharge status, suggesting that HHA patients were less medically complex than SNF and IRF patients. IRF patients were more dependent in discharge self-care even after controlling for severity. For the full discharge mobility regression model, urinary incontinence was the only significant covariate. For the patients in our U.S.-based study, direct discharge to home with home care was the optimal strategy for patients after total joint replacement surgery who were healthy and had social support. For sicker patients, availability of 24-hour medical and nursing care may be needed, but intensive therapy services did not seem to provide additional improvement in functional recovery in these patients. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  6. Hospital consumer assessment of healthcare providers and systems scores relating to pain following the incorporation of clinical pharmacists into patient education prior to joint replacement surgery.

    Science.gov (United States)

    Hefti, Erik; Remington, Michael; Lavallee, Charles

    2017-01-01

    Pharmacist involvement has been shown to improve various aspects of patient care. Patients undergoing knee and hip replacement surgery generally experience post-operative pain and discomfort. Pain control can impact patient satisfaction, as reported by the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey. The current pilot study aims to measure the potential impact that incorporating pharmacists into preoperative patient education programs has on the response to select HCAHPS questions. Patient responses to two select HCAHPS questions related to pain were recorded for a year prior to pharmacist involvement in a comprehensive preoperative patient education program (2012) and a year after pharmacists became actively involved (2013). In all reporting surgical patients, there was a modest 3.68% improvement in mean scores reflecting patient's feelings that hospital staff did "everything they could" to attend to their pain (mean 2012 =3.66, SD=0.63 versus mean 2013 =3.80, SD=0.43, p=0.018, Mann-Whitney U test). There was a non-significant 2.98% improvement in scores reflecting the level that pain was "well controlled" (mean 2012 =3.54, SD=0.651 versus mean 2013 =3.65, SD=0.554, p=0.069, Mann-Whitney U test) in surgical patients. The results suggest comprehensive pharmacist involvement in patient education prior to joint replacement surgery may impact HCAHPS scores related to pain control. While the observed potential improvements were modest, the current results justify larger, multi-institution prospective studies to better elucidate the impact pharmacists can have on pain management in patients undergoing joint replacement.

  7. Associations between preoperative Oxford hip and knee scores and costs and quality of life of patients undergoing primary total joint replacement in the NHS England: an observational study.

    Science.gov (United States)

    Eibich, Peter; Dakin, Helen A; Price, Andrew James; Beard, David; Arden, Nigel K; Gray, Alastair M

    2018-04-10

    To assess how costs and quality of life (measured by EuroQoL-5 Dimensions (EQ-5D)) before and after total hip replacement (THR) and total knee replacement (TKR) vary with age, gender and preoperative Oxford hip score (OHS) and Oxford knee score (OKS). Regression analyses using prospectively collected data from clinical trials, cohort studies and administrative data bases. UK secondary care. Men and women undergoing primary THR or TKR. The Hospital Episode Statistics data linked to patient-reported outcome measures included 602 176 patients undergoing hip or knee replacement who were followed up for up to 6 years. The Knee Arthroplasty Trial included 2217 patients undergoing TKR who were followed up for 12 years. The Clinical Outcomes in Arthroplasty Study cohort included 806 patients undergoing THR and 484 patients undergoing TKR who were observed for 1 year. EQ-5D-3L quality of life before and after surgery, costs of primary arthroplasty, costs of revision arthroplasty and the costs of hospital readmissions and ambulatory costs in the year before and up to 12 years after joint replacement. Average postoperative utility for patients at the 5th percentile of the OHS/OKS distribution was 0.61/0.5 for THR/TKR and 0.89/0.85 for patients at the 95th percentile. The difference between postoperative and preoperative EQ-5D utility was highest for patients with preoperative OHS/OKS lower than 10. However, postoperative EQ-5D utility was higher than preoperative utility for all patients with OHS≤46 and those with OKS≤44. In contrast, costs were generally higher for patients with low preoperative OHS/OKS than those with high OHS/OKS. For example, costs of hospital readmissions within 12 months after primary THR/TKR were £740/£888 for patients at the 5th percentile compared with £314/£404 at the 95th percentile of the OHS/OKS distribution. Our findings suggest that costs and quality of life associated with total joint replacement vary systematically with

  8. Cervical anterior hybrid technique with bi-level Bryan artificial disc replacement and adjacent segment fusion for cervical myelopathy over three consecutive segments.

    Science.gov (United States)

    Chen, Jiang; Xu, Lin; Jia, Yu-Song; Sun, Qi; Li, Jin-Yu; Zheng, Chen-Ying; Bai, Chun-Xiao; Yu, Qin-Sheng

    2016-05-01

    This study aimed to assess the preliminary clinical efficacy and feasibility of the hybrid technique for multilevel cervical myelopathy. Considering the many shortcomings of traditional treatment methods for multilevel cervical degenerative myelopathy, hybrid surgery (bi-level Bryan artificial disc [Medtronic Sofamor Danek, Memphis, TN, USA] replacement and anterior cervical discectomy and fusion) should be considered. Between March 2006 and November 2012, 108 patients (68 men and 40 women, average age 45years) underwent hybrid surgery. Based on the Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), and Odom's criteria, the clinical symptoms and neurological function before and after surgery were evaluated. Mean surgery duration was 90minutes, with average blood loss of 30mL. Mean follow-up duration was 36months. At the final follow-up, the mean JOA (± standard deviation) scores were significantly higher compared with preoperative values (15.08±1.47 versus 9.18±1.22; P<0.01); meanwhile, NDI values were markedly decreased (12.32±1.03 versus 42.68±1.83; P<0.01). Using Odom's criteria, the clinical outcomes were rated as excellent (76 patients), good (22 patients), fair (six patients), and poor (four patients). These findings indicate that the hybrid method provides an effective treatment for cervical myelopathy over three consecutive segments, ensuring a good clinical outcome. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. The impact of replacing sugar- by artificially-sweetened beverages on brain and behavioral responses to food viewing - An exploratory study.

    Science.gov (United States)

    Crézé, Camille; Notter-Bielser, Marie-Laure; Knebel, Jean-François; Campos, Vanessa; Tappy, Luc; Murray, Micah; Toepel, Ulrike

    2018-04-01

    Several studies indicate that the outcome of nutritional and lifestyle interventions can be linked to brain 'signatures' in terms of neural reactivity to food cues. However, 'dieting' is often considered in a rather broad sense, and no study so far investigated modulations in brain responses to food cues occurring over an intervention specifically aiming to reduce sugar intake. We studied neural activity and liking in response to visual food cues in 14 intensive consumers of sugar-sweetened beverages before and after a 3-month replacement period by artificially-sweetened equivalents. Each time, participants were presented with images of solid foods differing in fat content and taste quality while high-density electroencephalography was recorded. Contrary to our hypotheses, there was no significant weight loss over the intervention period and no changes were observed in food liking or in neural activity in regions subserving salience and reward attribution. However, neural activity in response to high-fat, sweet foods was significantly reduced from pre-to post-intervention in prefrontal regions often linked to impulse control. This decrease in activity was associated with weight loss failure, suggesting an impairment in individuals' ability to exert control and adjust their solid food intake over the intervention period. Our findings highlight the need to implement multidisciplinary approaches when aiming to help individuals lose body weight. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Prediction of the Vickers Microhardness and Ultimate Tensile Strength of AA5754 H111 Friction Stir Welding Butt Joints Using Artificial Neural Network

    Science.gov (United States)

    De Filippis, Luigi Alberto Ciro; Serio, Livia Maria; Facchini, Francesco; Mummolo, Giovanni; Ludovico, Antonio Domenico

    2016-01-01

    A simulation model was developed for the monitoring, controlling and optimization of the Friction Stir Welding (FSW) process. This approach, using the FSW technique, allows identifying the correlation between the process parameters (input variable) and the mechanical properties (output responses) of the welded AA5754 H111 aluminum plates. The optimization of technological parameters is a basic requirement for increasing the seam quality, since it promotes a stable and defect-free process. Both the tool rotation and the travel speed, the position of the samples extracted from the weld bead and the thermal data, detected with thermographic techniques for on-line control of the joints, were varied to build the experimental plans. The quality of joints was evaluated through destructive and non-destructive tests (visual tests, macro graphic analysis, tensile tests, indentation Vickers hardness tests and t thermographic controls). The simulation model was based on the adoption of the Artificial Neural Networks (ANNs) characterized by back-propagation learning algorithm with different types of architecture, which were able to predict with good reliability the FSW process parameters for the welding of the AA5754 H111 aluminum plates in Butt-Joint configuration. PMID:28774035

  11. Prediction of the Vickers Microhardness and Ultimate Tensile Strength of AA5754 H111 Friction Stir Welding Butt Joints Using Artificial Neural Network.

    Science.gov (United States)

    De Filippis, Luigi Alberto Ciro; Serio, Livia Maria; Facchini, Francesco; Mummolo, Giovanni; Ludovico, Antonio Domenico

    2016-11-10

    A simulation model was developed for the monitoring, controlling and optimization of the Friction Stir Welding (FSW) process. This approach, using the FSW technique, allows identifying the correlation between the process parameters (input variable) and the mechanical properties (output responses) of the welded AA5754 H111 aluminum plates. The optimization of technological parameters is a basic requirement for increasing the seam quality, since it promotes a stable and defect-free process. Both the tool rotation and the travel speed, the position of the samples extracted from the weld bead and the thermal data, detected with thermographic techniques for on-line control of the joints, were varied to build the experimental plans. The quality of joints was evaluated through destructive and non-destructive tests (visual tests, macro graphic analysis, tensile tests, indentation Vickers hardness tests and t thermographic controls). The simulation model was based on the adoption of the Artificial Neural Networks (ANNs) characterized by back-propagation learning algorithm with different types of architecture, which were able to predict with good reliability the FSW process parameters for the welding of the AA5754 H111 aluminum plates in Butt-Joint configuration.

  12. Prediction of the Vickers Microhardness and Ultimate Tensile Strength of AA5754 H111 Friction Stir Welding Butt Joints Using Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Luigi Alberto Ciro De Filippis

    2016-11-01

    Full Text Available A simulation model was developed for the monitoring, controlling and optimization of the Friction Stir Welding (FSW process. This approach, using the FSW technique, allows identifying the correlation between the process parameters (input variable and the mechanical properties (output responses of the welded AA5754 H111 aluminum plates. The optimization of technological parameters is a basic requirement for increasing the seam quality, since it promotes a stable and defect-free process. Both the tool rotation and the travel speed, the position of the samples extracted from the weld bead and the thermal data, detected with thermographic techniques for on-line control of the joints, were varied to build the experimental plans. The quality of joints was evaluated through destructive and non-destructive tests (visual tests, macro graphic analysis, tensile tests, indentation Vickers hardness tests and t thermographic controls. The simulation model was based on the adoption of the Artificial Neural Networks (ANNs characterized by back-propagation learning algorithm with different types of architecture, which were able to predict with good reliability the FSW process parameters for the welding of the AA5754 H111 aluminum plates in Butt-Joint configuration.

  13. Supracondylar femoral osteotomy and knee joint replacement during the same surgical procedure in a type A haemophiliac patient with knee flexion deformity and ankylosis.

    Science.gov (United States)

    Osma Rueda, Jose Luis; Oliveros Vargas, Alejandra; Sosa, Cristian David

    2017-03-01

    Haemophilia A is the cause of diverse musculoskeletal disorders such as ankylosis, arthritis and associated angular deformity. There are few reported cases in patients with haemophilia A in which simultaneous supracondylar femoral osteotomy and knee joint replacement has been performed to treat knee angular deformity and ankylosis. Here we present the case of an 18year old male patient, with an evolution of two years, who was unable to walk due to the presence of an untreated supracondylar fracture in the left femur and ipsilateral haemophilic arthropathy which led him to develop an ankylosis in flexion close to 70°. Supracondylar osteotomy of the femur and of the left knee joint was performed in the same surgical procedure. Bleeding control was achieved with a protocol of factor VIII supply. The patient was followed up for eight years, and recovered a 0 to 90° range of motion and regained his gait pattern. This case potentially provides a new alternative approach for haemophilia patients presenting with angular deformities and complex ankylosis. We suggest that mixed lesions of intra- and extra-articular deformity in haemophiliac patients can be corrected during the same surgical intervention. In addition, interdisciplinary management including haematology for operative and immediately postoperative control of intra-bleeding using factor VIII supply and control, combined with a controlled rehabilitation plan, can yield good functional outcomes in patients with haemophilic arthropathy. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. The associations of illness perceptions and self-efficacy with psychological well-being of patients in preparation for joint replacement surgery.

    Science.gov (United States)

    Magklara, Eleni; Morrison, Val

    2016-09-01

    Patient well-being on referral to surgery likely affects their surgical experience yet few studies examine pre-surgical correlates of well-being. Guided by the Common Sense Model of Self-Regulation and Social Cognitive theory, this study examined whether illness and emotional representations, general and domain self-efficacy were associated with pre-surgical well-being. The pre-surgical assessment of a three-wave prospective study is reported. Fifty-four hip and knee replacements patients (mean age = 69.33; SD = 8.57) were recruited in the pre-surgery educational clinic at a UK general hospital. Patients completed a questionnaire-pack including the Revised Illness Perceptions Questionnaire, the General Self-Efficacy Scale, the Self-Efficacy for Rehabilitation Outcome Scale, the Falls-Efficacy Scale, and the Short Form of Psychological Well-Being Index. Multiple hierarchical regression analyses showed that above and beyond demographic and clinical characteristics, negative emotional representations were associated with lower psychological well-being while strong general self-efficacy beliefs were positively related to psychological well-being. Independent of demographic and clinical characteristics, joint replacement patients' psychological well-being was associated with their cognitions and emotional reactions to their condition before surgery. Early interventions could potentially target these modifiable factors to improve pre-surgical well-being in this group of patients, with potential for additional post-surgical benefit.

  15. A prospective study of the association of patient expectations with changes in health-related quality of life outcomes, following total joint replacement.

    Science.gov (United States)

    Gonzalez Saenz de Tejada, Marta; Escobar, Antonio; Bilbao, Amaia; Herrera-Espiñeira, Carmen; García-Perez, Lidia; Aizpuru, Felipe; Sarasqueta, Cristina

    2014-07-23

    Patient expectations regarding surgery may be related to outcomes in total joint replacement (TJR). The aim of this study was to determine the association of patient expectations with health related quality of life (HRQoL) outcomes measured by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Short Form 12 (SF-12) and satisfaction with current symptoms measured on a 4-point Likert scale, one year after surgery, adjusting for Body Mass Index (BMI), age, gender, joint, education, previous intervention and baseline scores. Consecutive patients preparing for TJR of the knee or hip due to primary osteoarthritis (OA) in 15 hospitals in Spain were recruited for the study. Patients completed questionnaires before surgery and 12 months afterwards: five questions about expectations before surgery; an item to measure satisfaction; two HRQoL instruments-WOMAC and SF-12; as well as questions about sociodemographic information. To determine the association of patient expectations at baseline, with changes in HRQoL 12 months after surgery and with satisfaction, general linear models and logistic regression analysis were performed. A total of 892 patients took part in the study. Patients who had higher pain relief or ability to walk expectations improved more in HRQoL at 12 months. Moreover, patients with high daily activity expectations were more satisfied. Patients with higher baseline expectations for TJR, improved more in HRQoL at one year and had more likelihood to be satisfied than patients with lower expectations, adjusted for BMI, age, gender, joint, education, previous intervention and HRQoL baseline scores.

  16. The dynamics of patients' life quality indices under the conditions of two-stage knee joint replacement

    Directory of Open Access Journals (Sweden)

    Shpinyak S.P.

    2017-09-01

    Full Text Available  The aim: to analyze the changes in the life quality indices of the patients with deep periprosthetic joint infection of the knee under the two-stage surgical treatment. Material and Methods. 57 patients who underwent two-stage revision-ary treatment in Research Institute of Traumatology, Orthopedics and Neurosurgery were interviewed with life quality questionnaire Short Form Medical Outcomes Study (SF 36 v.1. Interview results were compared with standardized population indices of SF-36 scales for males and females. Results. In all groups regardless of sex there was a general tendency for an increase in physical and psychological health component up to mean population values after the first stage of surgery and further growth after the second stage. Rehabilitation potential of psychomotor health was higher in women than in men. The ability to handle stress was lower in direct ratio with the patients' age. Conclusion. Two-stage reendoprosthetic treatment with articulating antimicrobial spacer implantation having high grade of fixation is an effective treatment method for deep periprosthetic infection which increases physical health and improves social functioning of patients.

  17. Genomic replacement of native Cobitis lutheri with introduced C. tetralineata through a hybrid swarm following the artificial connection of river systems.

    Science.gov (United States)

    Kwan, Ye-Seul; Ko, Myeong-Hun; Won, Yong-Jin

    2014-04-01

    River connections via artificial canals will bring about secondary contacts between previously isolated fish species. Here, we present a genetic consequence of such a secondary contact between Cobitis fish species, C. lutheri in the Dongjin River, and C. tetralineata in the Seomjin River in Korea. The construction of water canals about 80 years ago has unidirectionally introduced C. tetralineata into the native habitat of C. lutheri, and then these species have hybridized in the main stream section of the Dongjin River. According to the divergence population genetic analyses of DNA sequence data, the two species diverged about 3.3 million years ago, which is interestingly coincident with the unprecedented paleoceanographic change that caused isolations of the paleo-river systems in northeast Asia due to sea-level changes around the late Pliocene. Multilocus genotypic data of nine microsatellites and three nuclear loci revealed an extensively admixed structure in the hybrid zone with a high proportion of various post-F1 hybrids. Surprisingly, pure native C. lutheri was absent in the hybrid zone in contrast to the 7% of pure C. tetralineata. Such a biased proportion must have resulted from the dominant influence of continually introducing C. tetralineata on the native C. lutheri which has no supply of natives from other tributaries to the hybrid zone due to numerous low-head dams. In addition, mating experiments indicated that there is no discernible reproductive isolation between them. All the results suggest that the gene pool of native C. lutheri is being rapidly replaced by that of continually introducing C. tetralineata through a hybrid swarm for the last 80 years, which will ultimately lead to the genomic extinction of natives in this hybrid zone.

  18. The concentration of manganese, iron, and strontium in hip joint bone obtained from patients undergoing hip replacement surgery.

    Science.gov (United States)

    Budis, Halina; Kalisinska, Elzbieta; Lanocha, Natalia; Kosik-Bogacka, Danuta; Sokolowski, Sebastian; Dobiecki, Konrad; Kolodziej, Lukasz; Bohatyrewicz, Andrzej

    2014-01-01

    The aim of this study was to determine the concentrations of manganese (Mn), iron (Fe) and strontium (Sr) in the cartilage with adjacent compact bone and spongy bone collected from patients after total hip replacement surgery. In addition, we examined relations between the concentrations of the metals in the bone and selected environmental factors. The concentration of Fe was the highest while Mn concentration was the lowest. The concentrations of Fe in the spongy bone in patients from larger cities were higher than in those living in smaller towns and villages. Significant correlations were found between Fe and Mn concentrations in the cartilage with adjacent compact bone and in the spongy bone, and between Mn and Sr in the spongy bone. In general, Mn, Fe and Sr concentrations in the bones of patients from NW Poland were lower than in other Polish regions and Europe, especially in industrialized countries. In conclusion, it seems that in addition to routine monitoring of the abiotic environment, it is essential to monitor concentrations of heavy metals having a long-term impact in humans. Copyright © 2013 Elsevier GmbH. All rights reserved.

  19. 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.

  20. Effect of storage temperature and equilibration time on polymethyl methacrylate (PMMA) bone cement polymerization in joint replacement surgery.

    Science.gov (United States)

    Koh, Bryan T H; Tan, J H; Ramruttun, Amit Kumarsing; Wang, Wilson

    2015-11-17

    In cemented joint arthroplasty, the handling characteristics (doughing, working, and setting times) of polymethyl methacrylate (PMMA) bone cement is important as it determines the amount of time surgeons have to optimally position an implant. Storage conditions (temperature and humidity) and the time given for PMMA cement to equilibrate to ambient operating theater (OT) temperatures are often unregulated and may lead to inconsistencies in its handling characteristics. This has not been previously studied. Hence, the purpose of this study was to investigate the effect of storage temperatures on the handling characteristics of PMMA cement and the duration of equilibration time needed at each storage temperature to produce consistent and reproducible doughing, setting, and working times. SmartSet® HV cement was stored at three different controlled temperatures: 20 °C (control), 24 °C, and 28 °C for at least 24 h prior to mixing. The cement components were then brought into a room kept at 20 °C and 50 % humidity. Samples were allowed to equilibrate to ambient conditions for 15, 30, 45, and 60 min. The cement components were mixed and the dough time, temperature-versus-time curve (Lutron TM-947SD, Lutron Electronics, Inc., Coopersburg, PA), and setting time were recorded. Analysis was performed using the two-way ANOVA test (IBM SPSS Statistics V.22). At 20 °C (control) storage temperature, the mean setting time was 534 ± 17 s. At 24 °C storage temperature, the mean setting time was 414 ± 6 s (p  0.05) with 60 min of equilibration. At 28 °C storage temperature, the mean setting time was 381 ± 8 s (p  0.05) with 60 min of equilibration. This study reflects the extent to which storage temperatures and equilibration times can potentially affect the handling characteristics of PMMA cement. We recommend institutions to have a well-regulated temperature and humidity-controlled facility for storage of bone cements and a protocol to

  1. High critical current YBa2Cu3O7 artificial joints using Ag foils as welding agent

    International Nuclear Information System (INIS)

    Iliescu, S; Granados, X; Bartolome, E; Sena, S; Carrilllo, A E; Puig, T; Obradors, X; Evetts, J E

    2004-01-01

    A new high quality joining technique of melt processed YBCO has been developed based on interfacial melting induced by a metallic silver foil inserted between two single domain YBCO tiles. This simple technique allows joining large monoliths to form the complex-shaped pieces required for many power applications. Hall probe magnetic flux profile analysis under magnetic field and high field magnetoresistance measurements demonstrate that the superconducting behaviour of the joint is indistinguishable from the bulk

  2. Evaluation of Artificial Caudal Fin for Fish Robot with Two Joints by Using Three-Dimensional Fluid-Structure Simulation

    Directory of Open Access Journals (Sweden)

    Yogo Takada

    2013-01-01

    Full Text Available A fish robot with image sensors is useful to research for underwater creatures such as fish. However, the propulsion velocity of a fish robot is very slow compared with live fish. It is necessary to swim at a speed several times faster than the speed of the current robots for various usages. Therefore, we are searching for the method of making the robot swim fast. The simulation before making the robot is important. We have made the computational simulation program of three-dimensional fluid-structure analysis. The flow around the caudal fin can be examined by analyzing the fin as an elastic body. We compared the results of numerical analysis with the results of PIV measurement. Both were agreed well. Because the performance of a fish robot with two joints is better than that of a fish robot with one joint, we searched for an excellent fin for the fish robot with two joints by using CFD. We confirmed that the swimming performance of a fish robot becomes very good when the caudal fin is rigid except for the root of the fin which is comparatively flexible.

  3. Operating theatre ventilation systems and microbial air contamination in total joint replacement surgery: results of the GISIO-ISChIA study.

    Science.gov (United States)

    Agodi, A; Auxilia, F; Barchitta, M; Cristina, M L; D'Alessandro, D; Mura, I; Nobile, M; Pasquarella, C

    2015-07-01

    Recent studies have shown a higher rate of surgical site infections in hip prosthesis implantation using unidirectional airflow ventilation compared with turbulent ventilation. However, these studies did not measure the air microbial quality of operating theatres (OTs), and assumed it to be compliant with the recommended standards for this ventilation technique. To evaluate airborne microbial contamination in OTs during hip and knee replacement surgery, and compare the findings with values recommended for joint replacement surgery. Air samplings were performed in 28 OTs supplied with unidirectional, turbulent and mixed airflow ventilation. Samples were collected using passive sampling to determine the index of microbial air contamination (IMA). Active sampling was also performed in some of the OTs. The average number of people in the OT and the number of door openings during the sampling period were recorded. In total, 1228 elective prosthesis procedures (60.1% hip and 39.9% knee) were included in this study. Of passive samplings performed during surgical activity in unidirectional airflow ventilation OTs (U-OTs) and mixed airflow OTs (M-OTs), 58.9% and 87.6% had IMA values >2, respectively. Of samplings performed during surgical activity in turbulent airflow OTs (T-OTs) and in turbulent airflow OTs with the surgical team wearing Steri-Shield Turbo Helmets (TH-OTs), 8.6% and 60% had IMA values ≤ 2, respectively. Positive correlation was found between IMA values and the number of people in the OT and the number of door openings (P systems always provide acceptable airborne bacterial counts. Copyright © 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  4. Synovial fluid protein adsorption on polymer-based artificial hip joint material investigated by MALDI-TOF mass spectrometry imaging

    Directory of Open Access Journals (Sweden)

    Sophie M. Fröhlich

    2014-09-01

    Full Text Available UHMW-PE (ultra-high molecular weight polyethylene, most frequently used material in acetabular cup replacement, is affected by the interaction with its surrounding synovial fluid. It is assumed that protein layer formation is of high importance for lubrication, however alters polymer characteristics. This study investigates in vitro protein adsorption on gamma-irradiated and Vitamin E doped UHMW-PE using synovia as modeling system. SDS-PAGE and MALDI-TOF mass spectrometry imaging showed adsorption of high abundance proteins in a mass range between 2 and 200 kDa. Protein layer formation was observed on planar UHMW-PE material, whereas morphologically modified UHMW-PE regions were highly affected by protein aggregation.

  5. The role of pain and functional impairment in the decision to recommend total joint replacement in hip and knee osteoarthritis: an international cross-sectional study of 1909 patients. Report of the OARSI-OMERACT Task Force on total joint replacement

    DEFF Research Database (Denmark)

    Gossec, L; Paternotte, S; Maillefert, J F

    2011-01-01

    : In all, 1909 patients were included (1130 knee/779 hip OA). Mean age was 66.4 [standard deviation (SD) 10.9] years, 58.1% were women; 628/1130 (55.6%) knee OA and 574/779 (73.7%) hip OA patients were recommended for TJR. Although patients recommended for TJR (yes vs no) had worse symptom levels [pain, 55......OBJECTIVE: To assess the pain and functional disability levels corresponding to an indication for total joint replacement (TJR) in hip and knee osteoarthritis (OA). METHODS: Design: International cross-sectional study in 10 countries. Patients: Consecutive outpatients with definite hip or knee OA...... attending an orthopaedic outpatient clinic. Gold standard measure for recommendation for TJR: Surgeon's decision that TJR is justified. Outcome measures: Pain (ICOAP: intermittent and constant osteoarthritis pain, 0-100) and functional impairment (HOOS-PS/KOOS-PS: Hip/Knee injury and Osteoarthritis Outcome...

  6. 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.

  7. 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.

  8. An in vitro simulation model to assess the severity of edge loading and wear, due to variations in component positioning in hip joint replacements.

    Science.gov (United States)

    O'Dwyer Lancaster-Jones, O; Williams, S; Jennings, L M; Thompson, J; Isaac, G H; Fisher, J; Al-Hajjar, M

    2017-09-23

    The aim of this study was to develop a preclinical in vitro method to predict the occurrence and severity of edge loading condition associated with the dynamic separation of the centres of the head and cup (in the absence of impingement) for variations in surgical positioning of the cup. Specifically, this study investigated the effect of both the variations in the medial-lateral translational mismatch between the centres of the femoral head and acetabular cup and the variations in the cup inclination angles on the occurrence and magnitude of the dynamic separation, the severity of edge loading, and the wear rate of ceramic-on-ceramic hip replacement bearings in a multi-station hip joint simulator during a walking gait cycle. An increased mismatch between the centres of rotation of the femoral head and acetabular cup resulted in an increased level of dynamic separation and an increase in the severity of edge loading condition which led to increased wear rate in ceramic-on-ceramic bearings. Additionally for a given translational mismatch, an increase in the cup inclination angle gave rise to increased dynamic separation, worst edge loading conditions, and increased wear. To reduce the occurrence and severity of edge loading, the relative positions (the mismatch) of the centres of rotation of the head and the cup should be considered alongside the rotational position of the acetabular cup. This study has considered the combination of mechanical and tribological factors for the first time in the medial-lateral axis only, involving one rotational angle (inclination) and one translational mismatch. © 2017 The Authors Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2017. © 2017 The Authors Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc.

  9. Five-year decreased incidence of surgical site infections following gastrectomy and prosthetic joint replacement surgery through active surveillance by the Korean Nosocomial Infection Surveillance System.

    Science.gov (United States)

    Choi, H J; Adiyani, L; Sung, J; Choi, J Y; Kim, H B; Kim, Y K; Kwak, Y G; Yoo, H; Lee, Sang-Oh; Han, S H; Kim, S R; Kim, T H; Lee, H M; Chun, H K; Kim, J-S; Yoo, J D; Koo, H-S; Cho, E H; Lee, K W

    2016-08-01

    Surveillance of healthcare-associated infection has been associated with a reduction in surgical site infection (SSI). To evaluate the Korean Nosocomial Infection Surveillance System (KONIS) in order to assess its effects on SSI since it was introduced. SSI data after gastrectomy, total hip arthroplasty (THA), and total knee arthroplasty (TKA) between 2008 and 2012 were analysed. The pooled incidence of SSI was calculated for each year; the same analyses were also conducted from hospitals that had participated in KONIS for at least three consecutive years. Standardized SSI rates for each year were calculated by adjusting for SSI risk factors. SSI trends were analysed using the Cochran-Armitage test. The SSI rate following gastrectomy was 3.12% (522/16,918). There was a significant trend of decreased crude SSI rates over five years. This trend was also evident in analysis of hospitals that had participated for more than three years. The SSI rate for THA was 2.05% (157/7656), which decreased significantly from 2008 to 2012. The risk factors for SSI after THA included the National Nosocomial Infections Surveillance risk index, trauma, reoperation, and age (60-69 years). The SSI rate for TKA was 1.90% (152/7648), which also decreased significantly during a period of five years. However, the risk-adjusted analysis of SSI did not show a significant decrease for all surgical procedures. The SSI incidence of gastrectomy and prosthetic joint replacement declined over five years as a result of active surveillance by KONIS. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  10. Artificial Gravity

    CERN Document Server

    Clément, Gilles

    2007-01-01

    Protecting the health, safety, and performance of exploration-class mission crews against the physiological deconditioning resulting from long-term weightlessness during transit and long-term reduced gravity during surface operations will require effective, multi-system countermeasures. Artificial gravity, which would replace terrestrial gravity with inertial forces generated by rotating the transit vehicle or by short-radius human centrifuge devices within the transit vehicle or surface habitat, has long been considered a potential solution. However, despite its attractiveness as an efficient

  11. Effect of replacing soybean protein with protein from porcupine joint vetch (Aeschynomene histrix BRA 9690) and stylo (Stylosanthes guianensis Composite) leaf meal on growth performance of native (Moo Lath) Lao pigs.

    Science.gov (United States)

    Phengsavanh, Phonepaseuth; Lindberg, Jan Erik

    2013-11-01

    The effect of replacing soybean crude protein (CP) with legume leaf meal (LLM) CP on feed intake, growth performance and carcass traits was studied in native female Moo Lath Lao pigs. The diets comprised one traditional diet (T) without soybean meal, one control diet (C) with soybean meal and six diets iso-nitrogenous with diet C in which soybean protein was replaced (33, 66 and 100 % of CP) with LLM CP from porcupine joint vetch (PLM) or Stylosanthes (SLM). Feed and water were offered ad libitum. Replacing soybean CP with LLM CP reduced (P  0.05) on feed conversion ratio (FCR). Increasing the replacement rate of soybean CP with LLM CP had a negative linear effect (P < 0.001) on DMI, CPI, MEI, final BW and ADG, and on all carcass traits except lean meat percentage. There were no differences in dressing percentage or organ weight and length between treatments. Supplementing diet T with soybean meal resulted in higher (P < 0.05) DMI, CPI and MEI, lower (P < 0.05) FCR, and higher (P < 0.05) final BW and ADG. Slaughter weight, hot carcass weight, eye muscle thickness, back fat, fat in carcass and lean meat were lower (P < 0.05) with diet T than diet C. In conclusion, LLM from stylo and porcupine joint vetch can be used as a CP source to partially replace soybean meal CP in the diet of growing native female Moo Lath Lao pigs.

  12. Description of the rates, trends and surgical burden associated with revision for prosthetic joint infection following primary and revision knee replacements in England and Wales: an analysis of the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man.

    Science.gov (United States)

    Lenguerrand, Erik; Whitehouse, Michael R; Beswick, Andrew D; Toms, Andrew D; Porter, Martyn L; Blom, Ashley W

    2017-07-10

    To describe the prevalence rates of revision surgery for the treatment of prosthetic joint infection (PJI) for patients undergoing knee replacement, their time trends, the cumulative incidence function of revision for PJI and estimate the burden of PJI at health service level. We analysed revision knee replacements performed due to a diagnosis of PJI and the linked index procedures recorded in the National Joint Registry from 2003 to 2014 for England and Wales. The cohort analysed consisted of 679 010 index primary knee replacements, 33 920 index revision knee replacements and 8247 revision total knee replacements performed due to a diagnosis of PJI. The prevalence rates, their time trends investigated by time from index surgery to revision for PJI, cumulative incidence functions and the burden of PJI (total procedures) were calculated. Overall linear trends were investigated with log-linear regression. The incidence of revision total knee replacement due to PJI at 2 years was 3.2/1000 following primary and 14.4/1000 following revision knee replacement, respectively. The prevalence of revision due to PJI in the 3 months following primary knee replacement has risen by 2.5-fold (95% CI 1.2 to 5.3) from 2005 to 2013 and 7.5-fold (95% CI 1.0 to 56.1) following revision knee replacement. Over 1000 procedures per year are performed as a consequence of knee PJI, an increase of 2.8 from 2005 to 2013. Overall, 75% of revisions were two-stage with an increase in use of single-stage from 7.9% in 2005 to 18.8% in 2014. Although the risk of revision due to PJI following knee replacement is low, it is rising, and coupled with the established and further predicted increased incidence of both primary and revision knee replacements, this represents an increasing and substantial treatment burden for orthopaedic service delivery in England and Wales. This has implications for future service design and the funding of individual and specialist centres. © Article author

  13. Artificial vision.

    Science.gov (United States)

    Zarbin, M; Montemagno, C; Leary, J; Ritch, R

    2011-09-01

    A number treatment options are emerging for patients with retinal degenerative disease, including gene therapy, trophic factor therapy, visual cycle inhibitors (e.g., for patients with Stargardt disease and allied conditions), and cell transplantation. A radically different approach, which will augment but not replace these options, is termed neural prosthetics ("artificial vision"). Although rewiring of inner retinal circuits and inner retinal neuronal degeneration occur in association with photoreceptor degeneration in retinitis pigmentosa (RP), it is possible to create visually useful percepts by stimulating retinal ganglion cells electrically. This fact has lead to the development of techniques to induce photosensitivity in cells that are not light sensitive normally as well as to the development of the bionic retina. Advances in artificial vision continue at a robust pace. These advances are based on the use of molecular engineering and nanotechnology to render cells light-sensitive, to target ion channels to the appropriate cell type (e.g., bipolar cell) and/or cell region (e.g., dendritic tree vs. soma), and on sophisticated image processing algorithms that take advantage of our knowledge of signal processing in the retina. Combined with advances in gene therapy, pathway-based therapy, and cell-based therapy, "artificial vision" technologies create a powerful armamentarium with which ophthalmologists will be able to treat blindness in patients who have a variety of degenerative retinal diseases.

  14. A prospective, single-centre study on patient outcomes following temporomandibular joint replacement using a custom-made Biomet TMJ prosthesis

    DEFF Research Database (Denmark)

    Aagaard, Esben; Thygesen, T.

    2014-01-01

    This study describes the clinical variables in 61 patients following total alloplastic temporomandibular joint reconstruction (TJR) in which the Biomet Microfixation Patient-Patient-Matched TMJ Implant was used. All patients were classified using the Wilkes classification. The visual analogue sca...

  15. Ankle replacement

    Science.gov (United States)

    Ankle arthroplasty - total; Total ankle arthroplasty; Endoprosthetic ankle replacement; Ankle surgery ... Ankle replacement surgery is most often done while you are under general anesthesia. This means you will ...

  16. A Comparison of Anterior Cervical Discectomy and Fusion versus Fusion Combined with Artificial Disc Replacement for Treating 3-Level Cervical Spondylotic Disease.

    Science.gov (United States)

    Jang, Seo-Ryang; Lee, Sang-Bok; Cho, Kyoung-Suok

    2017-11-01

    The purpose of this study is to evaluate the efficacy and safety of 3-level hybrid surgery (HS), which combines fusion and cervical disc replacement (CDR), compared to 3-level fusionin patient with cervical spondylosis involving 3 levels. Patients in the anterior cervical discectomy and fusion (ACDF) group (n=30) underwent 3-level fusion and the HS group (n=19) underwent combined surgery with fusion and CDR. Clinical outcomes were evaluated using the visual analogue scale for the arm, the neck disability index (NDI), Odom criteria and postoperative complications. The cervical range of motion (ROM), fusion rate and adjacent segments degeneration were assessed with radiographs. Significant improvements in arm pain relief and functional outcome were observed in ACDF and HS group. The NDI in the HS group showed better improvement 6 months after surgery than that of the ACDF group. The ACDF group had a lower fusion rate, higher incidence of device related complications and radiological changes in adjacent segments compared with the HS group. The better recovery of cervical ROM was observed in HS group. However, that of the ACDF group was significantly decreased and did not recover. The HS group was better than the ACDF group in terms of NDI, cervical ROM, fusion rate, incidence of postoperative complications and adjacent segment degeneration.

  17. 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

  18. Finite element model predicts the biomechanical performance of cervical disc replacement and fusion hybrid surgery with various geometry of ball-and-socket artificial disc.

    Science.gov (United States)

    Li, Yang; Fogel, Guy R; Liao, Zhenhua; Liu, Weiqiang

    2017-08-01

    Few finite element studies have investigated changes in cervical biomechanics with various prosthesis design parameters using hybrid surgery (HS), and none have investigated those combined different HS strategies. The aim of our study was to investigate the effect of ball-and-socket prosthesis geometry on the biomechanical performance of the cervical spine combined with two HS constructs. Two HS strategies were conducted: (1) ACDF at C4-C5 and anterior cervical disc replacement (ACDR) at C5-C6 (ACDF/ACDR), and (2) ACDR/ACDF. Three different prostheses were used for each HS strategy: prosthesis with the core located at the center of the inferior endplate with a radius of 5 mm (BS-5) or 6 mm (BS-6), or with a 5 mm radius core located 1 mm posterior to the center of the inferior endplate (PBS-5). Flexion and extension motions were simulated under displacement control. The flexion motions in supra- and infra-adjacent levels increased in all cases. The corresponding extension motions increased with all prostheses in ACDR/ACDF group. The stiffness in flexion and extension increased with all HS models, except for the extension stiffness with ACDF/ACDR. The facet stresses between the index and infra-adjacent level in ACDR/ACDF were significantly greater than those in the intact model . The stresses on the BS-5 UHMWPE core were greater than the yield stress. The core radii and position did not significantly affect the moments, ROM, and facet stress in extension. However, the moments and ROM in flexion were easily affected by the position. The results implied that the large core radii and posterior core position in ACDR designs may reduce the risk of subsidence and wear in the long term as they showed relative low stress . The ACDF/ACDR surgery at C4-C6 level may be an optimal treatment for avoiding accelerating the degeneration of adjacent segments.

  19. Comparative, validity and responsiveness of the HOOS-PS and KOOS-PS to the WOMAC physical function subscale in total joint replacement for osteoarthritis

    DEFF Research Database (Denmark)

    Davis, A M; Perruccio, A V; Canizares, M

    2009-01-01

    OBJECTIVE: To evaluate the internal consistency of the Hip disability and Osteoarthritis Outcome Score-Physical Function Short-form (HOOS-PS) and the Knee injury and Osteoarthritis Outcome Score-Physical Function Short-form (KOOS-PS) in total hip replacement (THR) and total knee (TKR) replacement....... Construct validity and responsiveness were compared to the Western Ontario McMaster Universities' Osteoarthritis Index (WOMAC) Likert 3.0 physical function (PF) subscale and the PF excluding the items in the short measures (PF-exclusions). METHODS: Participants completed the full HOOS or KOOS, measures...... and PF-exclusions with fatigue, CPG, anxiety and depression and HOOS/KOOS pain scales would differ by magnitudes of response means (SRMs) were calculated for the HOOS-PS, KOOS-PS, PF and PF-exclusions and hypothesized to be >1. RESULTS: The THR group (n=201) had a mean age of 62...

  20. Pre-operative self-efficacy education vs. usual care for patients undergoing joint replacement surgery: a pilot randomised controlled trial.

    Science.gov (United States)

    Cooke, Marie; Walker, Rachel; Aitken, Leanne M; Freeman, Andrea; Pavey, Sharlene; Cantrill, Ruth

    2016-03-01

    Hip and knee replacement is a major surgical procedure performed worldwide. Despite 20 or so years of clinical research and care guidelines, the management of acute postoperative pain continues to be a concern. A growing number of self-efficacy strategies are being included in education programs for patients to enable then to have a central role in managing their illness and symptoms. The purpose of this pilot study was to evaluate the feasibility of testing an education intervention to improve self-efficacy in patients undergoing hip or knee replacement. A single-blinded, parallel, pilot randomised control trial design was used. Ninety-one patients undergoing hip or knee replacement surgery were randomly assigned to an intervention or control group. Intervention group participants were given a DVD demonstrating self-efficacy activities to undertake four times before admission. Feasibility criteria related to recruitment, protocol adherence and missing data were assessed. Participants were assessed for pain, anxiety, self-efficacy and healthcare utilisation. In relation to recruitment, 55% of screened patients were eligible and of these 81% enrolled (n = 91). Exclusion following randomisation was 10% with missing data ranging from 0 to 20.7%. Nineteen per cent of participants were lost to follow up in the control group and 20% lost to follow up in DVD group. Protocol adherence to components of the intervention varied. Both groups were generally satisfied with pain management during hospitalisation, and there were no differences in groups on clinical outcome measures. Preliminary evidence for the benefits of self-efficacy-based education for patients undergoing hip or knee replacement was identified. Additional findings included a need to strengthen the intervention and reducing the number of data collection points to improve the protocol, missing data and numbers lost to follow up before a larger trial is undertaken. © 2015 Nordic College of Caring Science.

  1. Hospital consumer assessment of healthcare providers and systems scores relating to pain following the incorporation of clinical pharmacists into patient education prior to joint replacement surgery

    OpenAIRE

    Hefti, Erik; Remington, Michael; Lavallee, Charles

    2017-01-01

    Background: Pharmacist involvement has been shown to improve various aspects of patient care. Patients undergoing knee and hip replacement surgery generally experience post-operative pain and discomfort. Pain control can impact patient satisfaction, as reported by the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey. Objective: The current pilot study aims to measure the potential impact that incorporating pharmacists into preoperative patient education pro...

  2. In vitro validation of a technique for assessment of canine and feline elbow joint collateral ligament integrity and description of a new method for collateral ligament prosthetic replacement.

    Science.gov (United States)

    Farrell, Michael; Draffan, Davinia; Gemmill, Toby; Mellor, Dominic; Carmichael, Stuart

    2007-08-01

    To assess the ability of an operator to differentiate intact from transected canine and feline elbow joint collateral ligaments (CL) using a reported manipulative test (Campbell's test) and to determine the potential for elbow joint luxation in canine and feline elbows with intact, transected, and surgically stabilized CL. In vitro biomechanical study. Canine (n=6) and feline cadavers (n=3). Thoracic limb specimens were mounted on a custom-built jig with the elbows and carpi fixed in 90 degrees of flexion. Angles of pronation and supination were recorded after applying rotational forces to the manus. Attempts were made to manually luxate each elbow with intact CL. Constructs were re-evaluated after sequential sectioning of the medial (MCL) and lateral (LCL) collateral ligaments and after insertion of a new CL prosthesis. Mean (+/-SD) angles of rotation in dogs increased from 27.3+/-8 degrees (range, 16.7-41.3 degrees ) in pronation to 58.9+/-9.2 degrees (range, 38-88.3 degrees ) after sectioning the MCL and from 45.5+/-10.8 degrees (range, 30.7-67.3 degrees ) in supination to 68.9+/-17.2 degrees (range, 45-94 degrees ) after sectioning the LCL. Angles of pronation and supination were subject to significant interanimal variability, with a strong correlation between increasing animal weight and smaller angles of rotation. Elbow luxation in dogs was not possible unless at least the LCL was transected. In cats, mean angles of rotation increased from 49.8+/-14.9 degrees (range, 30.7-70 degrees ) in pronation to 99.1+/-17.6 degrees (range, 79-111.7 degrees ) after sectioning the MCL and from 128.7+/-18.8 degrees (range, 108.3-151.7 degrees ) in supination to 166.7+/-13.1 degrees (range, 157.3-181.7 degrees ) after sectioning the LCL. Luxation in cats was not possible unless both CL were cut. Use of the ligament prosthesis without primary CL repair reliably prevented reluxation in all canine and feline elbows. Campbell's test allowed reliable differentiation of intact

  3. 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 ...

  4. Parallel artificial liquid membrane extraction

    DEFF Research Database (Denmark)

    Gjelstad, Astrid; Rasmussen, Knut Einar; Parmer, Marthe Petrine

    2013-01-01

    This paper reports development of a new approach towards analytical liquid-liquid-liquid membrane extraction termed parallel artificial liquid membrane extraction. A donor plate and acceptor plate create a sandwich, in which each sample (human plasma) and acceptor solution is separated by an arti...... by an artificial liquid membrane. Parallel artificial liquid membrane extraction is a modification of hollow-fiber liquid-phase microextraction, where the hollow fibers are replaced by flat membranes in a 96-well plate format....

  5. Insights from the design and implementation of a single-entry model of referral for total joint replacement surgery: Critical success factors and unanticipated consequences.

    Science.gov (United States)

    Damani, Zaheed; MacKean, Gail; Bohm, Eric; Noseworthy, Tom; Wang, Jenney Meng Han; DeMone, Brie; Wright, Brock; Marshall, Deborah A

    2018-02-01

    Single-entry models (SEMs) in healthcare allow patients to see the next-available provider and have been shown to improve waiting times, access and patient flow for preference-sensitive, scheduled services. The Winnipeg Central Intake Service (WCIS) for hip and knee replacement surgery was implemented to improve access in the Winnipeg Regional Health Authority. This paper describes the system's design/implementation; successes, challenges, and unanticipated consequences. On two occasions, during and following implementation, we interviewed all members of the WCIS project team, including processing engineers, waiting list coordinators, administrators and policy-makers regarding their experiences. We used semi-structured telephone interviews to collect data and qualitative thematic analysis to analyze and interpret the findings. Respondents indicated that the overarching objectives of the WCIS were being met. Benefits included streamlined processes, greater patient access, improved measurement and monitoring of outcomes. Challenges included low awareness, change readiness, and initial participation among stakeholders. Unanticipated consequences included workload increases, confusion around stakeholder expectations and under-reporting of data by surgeons' offices. Critical success factors for implementation included a requirement for clear communication, robust data collection, physician leadership and patience by all, especially implementation teams. Although successfully implemented, key lessons and critical success factors were learned related to change management, which if considered and applied, can reduce unanticipated consequences, improve uptake and benefit new models of care. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Artificial intelligence

    CERN Document Server

    Hunt, Earl B

    1975-01-01

    Artificial Intelligence provides information pertinent to the fundamental aspects of artificial intelligence. This book presents the basic mathematical and computational approaches to problems in the artificial intelligence field.Organized into four parts encompassing 16 chapters, this book begins with an overview of the various fields of artificial intelligence. This text then attempts to connect artificial intelligence problems to some of the notions of computability and abstract computing devices. Other chapters consider the general notion of computability, with focus on the interaction bet

  7. A comparative study of generalized linear mixed modelling and artificial neural network approach for the joint modelling of survival and incidence of Dengue patients in Sri Lanka

    Science.gov (United States)

    Hapugoda, J. C.; Sooriyarachchi, M. R.

    2017-09-01

    Survival time of patients with a disease and the incidence of that particular disease (count) is frequently observed in medical studies with the data of a clustered nature. In many cases, though, the survival times and the count can be correlated in a way that, diseases that occur rarely could have shorter survival times or vice versa. Due to this fact, joint modelling of these two variables will provide interesting and certainly improved results than modelling these separately. Authors have previously proposed a methodology using Generalized Linear Mixed Models (GLMM) by joining the Discrete Time Hazard model with the Poisson Regression model to jointly model survival and count model. As Aritificial Neural Network (ANN) has become a most powerful computational tool to model complex non-linear systems, it was proposed to develop a new joint model of survival and count of Dengue patients of Sri Lanka by using that approach. Thus, the objective of this study is to develop a model using ANN approach and compare the results with the previously developed GLMM model. As the response variables are continuous in nature, Generalized Regression Neural Network (GRNN) approach was adopted to model the data. To compare the model fit, measures such as root mean square error (RMSE), absolute mean error (AME) and correlation coefficient (R) were used. The measures indicate the GRNN model fits the data better than the GLMM model.

  8. The role of custom-made prosthesis for temporomandibular joint replacement Papel de la prótesis hecha a medida para la sustitución de la articulación temporomandibular

    Directory of Open Access Journals (Sweden)

    Louis G. Mercuri

    2013-03-01

    Full Text Available Alloplastic temporomandibular joint replacement (TMJ TJR presents unique problems due to the integral and multifaceted roles this joint plays within the stomatognathic system to establish and maintain appropriate mandibular function and form. The TMJ not only acts as a secondary mandibular growth center pre-puberty, but is also crucial in maintaining proper mastication, speech, airway support and deglutition. Further, these essential life functions place the TMJ under more cyclical loading and unloading than any other body joint over a lifetime. Therefore, when TMJ TJR is indicated the device chosen must be able to provide long-term mandibular function and form outcomes. End-stage TMJ pathology accompanied by physiological function and anatomical form distortions dictates the need for replacement. Due to the complex nature of joint related masticatory muscle functional and anatomical associations, it is unreasonable to expect an autogenous reconstructed TMJ or an alloplastic replaced TMJ can be returned to "normal" pre-morbid function. Therefore, as is understood with any orthopaedic joint replacement, patient and surgeon must agree and accept that there will always be some functional disability involved with any reconstructed or replaced TMJ. Further, in the multiply operated, anatomically distorted patients, chronic neuropathic centrally mediated pain will always be a major component of their disability. Therefore, it is imperative that surgeon and patient understand that the primary goal of any TMJ TJR is the restoration mandibular function and form and that any pain relief must be considered of only secondary benefit. This paper will discuss the role of custom TMJ TJR devices have in the management of severe and debilitating TMJ disorders.La sustitución aloplástica de la articulación temporomandibular plantea problemas exclusivos debido al papel esencial y polifacético que esta articulación desempeña en el sistema estomatognático para

  9. Shoulder replacement

    Science.gov (United States)

    ... problem. Many people are able to return to sports such as golf, swimming, gardening, bowling, and others. Your new shoulder joint will last longer if less stress is placed on it. With normal use, a ...

  10. An electrochemical investigation of TMJ implant metal alloys in an artificial joint fluid environment: the influence of pH variation.

    Science.gov (United States)

    Royhman, Dmitry; Radhakrishnan, Rashmi; Yuan, Judy Chia-Chun; Mathew, Mathew T; Mercuri, Louis G; Sukotjo, Cortino

    2014-10-01

    To investigate the corrosion behaviour of commonly used TMJ implants alloys (CoCrMo and Ti6Al4V) under simulated physiological conditions. Corrosion behaviour was evaluated using standard electrochemical corrosion techniques and galvanic corrosion techniques as per ASTM standards. Standard electrochemical tests (E(corr), I(corr), R(p) and C(f)) were conducted in bovine calf serum (BCS), as a function of alloys type and different pHs. Galvanic corrosion tests were conducted in BCS at a pH of 7.6. Alloy surfaces were characterized using white-light interferometry (WLI) and scanning electron microscopy (SEM). The potentiodynamic test results exhibited the enhanced passive layer growth and a better corrosion resistance of Ti6Al4V compared to CoCrMo. Electrochemical impedance spectroscopy measurements demonstrated the influence of protein as a function of pH on corrosion mechanisms/kinetics. Galvanic coupling was not a major contributor to corrosion. SEM and WLI images demonstrated a significantly higher in surface roughness in CoCrMo after corrosion. The results of this study suggest that Ti6Al4V shows superior corrosion behaviour to CoCrMo due to its strong passive layer, simulated joint fluid components can affect the electrochemical nature of the metal/electrolyte interface as a function of pH, and the galvanic effect of coupling CoCrMo and Ti6Al4V in a single joint is weak. Published by Elsevier Ltd.

  11. How the increase of the cervical disc space height affects the facet joint: an anatomy study.

    Science.gov (United States)

    Liu, Jiayong; Ebraheim, Nabil A; Haman, Steven P; Sanford, Chris G; Sairyo, Koichi; Faizan, Ahmad; Woldenberg, Lee; Goel, Vijay K

    2006-05-20

    In vitro study on the effect of increasing the height of the cervical disc space on the facet joint. To demonstrate how facet joint articulation is affected by increasing the cervical disc space height. A surgeon attempts to increase the disc space and inserts a larger artificial disc than normal in order to keep the intervertebral foramen open and the prosthesis stable. However, it is hypothesized by the current authors that this procedure could have an adverse effect on the facet joints. Computerized tomography images passing through the disc space and the center of the C4-C7 facet joints (sagittal plane) were obtained from 15 cadaveric cervical spine specimens. A 1-mm incremental increase to a total 5 mm in disc space height was performed to simulate the changes seen in disc replacement. The change in the facet joint articulation overlap and space in the sagittal plane at normal and each displacement was measured. Each 1-mm incremental increase in disc space at C4-C5 translated to a decrease in the facet joint articulation overlap in the sagittal plane by approximately 8%. The mean facet joint space increased approximately 0.8 mm. At the C5-C6 and the C6-C7 levels, the articulation overlap decreased by approximately 7% and the facet joint space increased approximately 0.8 mm. There is a significant decrease of the facet joint articulation overlap in the sagittal plane and an increase in the facet joint space following an increase in the cervical disc space. The inappropriate increase of the disc space height may result in facet joint subluxation and could lead to the accelerated failure of the artificial disc.

  12. Replacing penalties

    Directory of Open Access Journals (Sweden)

    Vitaly Stepashin

    2017-01-01

    Full Text Available УДК 343.24The subject. The article deals with the problem of the use of "substitute" penalties.The purpose of the article is to identify criminal and legal criteria for: selecting the replacement punishment; proportionality replacement leave punishment to others (the formalization of replacement; actually increasing the punishment (worsening of legal situation of the convicted.Methodology.The author uses the method of analysis and synthesis, formal legal method.Results. Replacing the punishment more severe as a result of malicious evasion from serving accused designated penalty requires the optimization of the following areas: 1 the selection of a substitute punishment; 2 replacement of proportionality is serving a sentence other (formalization of replacement; 3 ensuring the actual toughening penalties (deterioration of the legal status of the convict. It is important that the first two requirements pro-vide savings of repression in the implementation of the replacement of one form of punishment to others.Replacement of punishment on their own do not have any specifics. However, it is necessary to compare them with the contents of the punishment, which the convict from serving maliciously evaded. First, substitute the punishment should assume a more significant range of restrictions and deprivation of certain rights of the convict. Second, the perfor-mance characteristics of order substitute the punishment should assume guarantee imple-mentation of the new measures.With regard to replacing all forms of punishment are set significant limitations in the application that, in some cases, eliminates the possibility of replacement of the sentence, from serving where there has been willful evasion, a stricter measure of state coercion. It is important in the context of the topic and the possibility of a sentence of imprisonment as a substitute punishment in cases where the original purpose of the strict measures excluded. It is noteworthy that the

  13. Using a scale-bridging technique to determine the effect of elastic properties on stress distribution around the femoral stem of an artificial hip joint with a simplified geometry

    Science.gov (United States)

    Jeong, C. U.; Lee, S.-C.; Rhee, H. N.; Park, K. S.; Choi, S.-H.

    2014-07-01

    A scale-bridging technique was used to investigate the effect of the elastic properties of β-Ti alloys on the stress distribution around the femoral stem of an artificial hip joint with a simplified geometry when under an external loading. The anisotropic elastic constants of single-crystalline β-Ti alloys (TN1: Ti-18.75 at% Nb, TN2: Ti-37.5 at% Nb, and TN3: Ti-43.75 at% Nb) were calculated using an ab-initio technique that was based on density functional theory calculation. The single-crystalline elastic constants calculated via the ab-initio technique were used to calculate the elastic constants of polycrystal β-Ti alloys using an elastic selfconsistent scheme. Finite element analysis based on the elastic constants of polycrystalline β-Ti alloys for a femoral stem was conducted to calculate the above-mentioned stress distribution. The model system consisting of a TN1 alloy exhibited a relatively high level of von Mises stress on the surface of cancellous and cortical bones compared to model systems consisting of TN2, TN3 alloys and commercial biomaterials (Ti-6Al-4V alloy and 316STS). The thickness of the cancellous bone between the femoral stem and the cortical bone affected the stress concentration on the surface of the cortical bone.

  14. Knee Replacement

    Science.gov (United States)

    ... days. Medications prescribed by your doctor should help control pain. During the hospital stay, you'll be encouraged to move your ... exercise your new knee. After you leave the hospital, you'll continue physical ... mobility and a better quality of life. And most knee replacements can be ...

  15. [The artificial heart. Current experiences].

    Science.gov (United States)

    Loisance, D; Deleuze, P

    1989-06-01

    Various assistance or replacement systems, usually including pneumatic pumps, are now used in human medicine to treat irreversible shocks. These systems are still very far from the ideal artificial heart, but they enable the ventricular work to be partially or totally achieved for a limited length of time, thus ensuring the patient's survival pending heart transplantation. The two systems most frequently used nowadays, i.e. orthotopic ventricular prosthesis or "internal artificial heart" and ventricular shunt or "external artificial heart" are described. The clinical experience available provides a first evaluation of the true performance of these systems.

  16. Artificial Consciousness or Artificial Intelligence

    OpenAIRE

    Spanache Florin

    2017-01-01

    Artificial intelligence is a tool designed by people for the gratification of their own creative ego, so we can not confuse conscience with intelligence and not even intelligence in its human representation with conscience. They are all different concepts and they have different uses. Philosophically, there are differences between autonomous people and automatic artificial intelligence. This is the difference between intelligence and artificial intelligence, autonomous versus a...

  17. Substituição do leite de cabra por soro de queijo bovino para cabritos alpinos Replacement of goat milk for cattle cheese whey in artificial feeding of Alpine kids

    Directory of Open Access Journals (Sweden)

    Roberto Germano Costa

    2010-04-01

    Full Text Available O trabalho foi conduzido para avaliar a substituição do leite de cabra por soro de queijo bovino no aleitamento de cabritos alpinos. Os animais foram distribuídos em delineamento inteiramente casualizado, em arranjo fatorial 4 × 2, composto de quatro níveis de substituição do leite de cabra por soro de queijo (0, 15, 30 e 45% e dois sexos (três machos e quatro fêmeas por tratamento. A inclusão do soro de queijo na dieta não afetou o desenvolvimento ponderal dos cabritos dos 7 aos 42 dias de idade. Os cabritos alimentados com leite de cabra apresentaram maiores pesos finais, em torno de 13,0 kg; consumiram 70,0 litros/animal de leite de cabra, 172,0 g MS/animal/dia de concentrado e tiveram ganho médio de 137,5 g/dia. Nos cabritos alimentados com a dieta com 15, 30 e 45% de soro de queijo, os pesos finais foram de 11,1; 9,88 e 10,27 kg; o consumo de leite foi de 59,5; 49,0 e 38,4 litros/animal; e o de concentrado, 148,0; 117,0 e 135 g MS/animal/dia, com ganhos de 122,2; 99,5 e 100,8 g/dia, respectivamente. A conversão alimentar não diferiu entre as dietas. O efeito do sexo evidenciou-se a partir dos 21 dias de idade, mas não houve interação dieta × sexo. Ao final do estudo, aos 70 dias de idade, o peso dos machos (12,4 kg foi maior que o das fêmeas (10,6 kg. A maior rentabilidade média (168,15% foi obtida com o fornecimento dos níveis mais altos de soro de leite. O aleitamento de cabritos com até 45% de soro de queijo é tecnicamente viável e proporciona melhor retorno econômico. O uso de leite integral de cabra para criação de cabritos em rebanhos leiteiros é economicamente inviável.The objective of this work was to evaluate the replacement of whole goat milk for cattle cheese whey in the artificial nursing of alpine kids. The animals were distributed in a complete randomized design in a 4 × 2 factorial arrangement made up with four levels of goat milk replacing for cheese whey (0, 15, 30 and 45% and two sexes (three

  18. FLUID MECHANICS OF ARTIFICIAL HEART VALVES

    OpenAIRE

    Dasi, Lakshmi P; Simon, Helene A; Sucosky, Philippe; Yoganathan, Ajit P

    2009-01-01

    1. Artificial heart valves have been in use for over five decades to replace diseased heart valves. Since the first heart valve replacement performed with a caged-ball valve, more than 50 valve designs have been developed, differing principally in valve geometry, number of leaflets and material. To date, all artificial heart valves are plagued with complications associated with haemolysis, coagulation for mechanical heart valves and leaflet tearing for tissue-based valve prosthesis. For mecha...

  19. Artificial intelligence

    CERN Document Server

    Ennals, J R

    1987-01-01

    Artificial Intelligence: State of the Art Report is a two-part report consisting of the invited papers and the analysis. The editor first gives an introduction to the invited papers before presenting each paper and the analysis, and then concludes with the list of references related to the study. The invited papers explore the various aspects of artificial intelligence. The analysis part assesses the major advances in artificial intelligence and provides a balanced analysis of the state of the art in this field. The Bibliography compiles the most important published material on the subject of

  20. Artificial Reefs

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An artificial reef is a human-made underwater structure, typically built to promote marine life in areas with a generally featureless bottom, control erosion, block...

  1. Artificial Metalloenzymes

    NARCIS (Netherlands)

    Rosati, Fiora; Roelfes, Gerard

    Artificial metalloenzymes have emerged as a promising approach to merge the attractive properties of homogeneous catalysis and biocatalysis. The activity and selectivity, including enantioselectivity, of natural metalloenzymes are due to the second coordination sphere interactions provided by the

  2. Artificial sweeteners

    DEFF Research Database (Denmark)

    Raben, Anne Birgitte; Richelsen, Bjørn

    2012-01-01

    Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie......-containing sweeteners. The purpose of this review is to summarize the current evidence on the effect of artificial sweeteners on body weight, appetite, and risk markers for diabetes and CVD in humans....

  3. Load environment of rail joint bars - phase I, effects of track parameters on rail joint stresses and crack growth.

    Science.gov (United States)

    2013-04-01

    The load environment of joint bars was assessed under a variety of loading and track conditions. Bending stresses, thermal stresses, and residual stresses were measured on commonly used joint bars. Crack growth rates from artificially induced cracks ...

  4. An ankle-foot orthosis powered by artificial pneumatic muscles.

    Science.gov (United States)

    Ferris, Daniel P; Czerniecki, Joseph M; Hannaford, Blake

    2005-05-01

    We developed a pneumatically powered orthosis for the human ankle joint. The orthosis consisted of a carbon fiber shell, hinge joint, and two artificial pneumatic muscles. One artificial pneumatic muscle provided plantar flexion torque and the second one provided dorsiflexion torque. Computer software adjusted air pressure in each artificial muscle independently so that artificial muscle force was proportional to rectified low-pass-filtered electromyography (EMG) amplitude (i.e., proportional myoelectric control). Tibialis anterior EMG activated the artificial dorsiflexor and soleus EMG activated the artificial plantar flexor. We collected joint kinematic and artificial muscle force data as one healthy participant walked on a treadmill with the orthosis. Peak plantar flexor torque provided by the orthosis was 70 Nm, and peak dorsiflexor torque provided by the orthosis was 38 Nm. The orthosis could be useful for basic science studies on human locomotion or possibly for gait rehabilitation after neurological injury.

  5. Artificial Diets for Mosquitoes

    Directory of Open Access Journals (Sweden)

    Kristina K. Gonzales

    2016-12-01

    Full Text Available Mosquito-borne diseases are responsible for more than a million human deaths every year. Modern mosquito control strategies such as sterile insect technique (SIT, release of insects carrying a dominant lethal (RIDL, population replacement strategies (PR, and Wolbachia-based strategies require the rearing of large numbers of mosquitoes in culture for continuous release over an extended period of time. Anautogenous mosquitoes require essential nutrients for egg production, which they obtain through the acquisition and digestion of a protein-rich blood meal. Therefore, mosquito mass production in laboratories and other facilities relies on vertebrate blood from live animal hosts. However, vertebrate blood is expensive to acquire and hard to store for longer times especially under field conditions. This review discusses older and recent studies that were aimed at the development of artificial diets for mosquitoes in order to replace vertebrate blood.

  6. Time-dependent elastohydrodynamic lubrication analysis of total knee replacement under walking conditions.

    Science.gov (United States)

    Su, Yonglin; Yang, Peiran; Fu, Zengliang; Jin, Zhongmin; Wang, Chengtao

    2011-06-01

    This work is concerned with the lubrication analysis of artificial knee joints, which plays an increasing significant role in clinical performance and longevity of components. Time-dependent elastohydrodynamic lubrication analysis for normal total knee replacement is carried out under the cyclic variation in both load and speed representative of normal walking. An equivalent ellipsoid-on-plane model is adopted to represent an actual artificial knee. A full numerical method is developed to simultaneously solve the Reynolds and elasticity equations using the multigrid technique. The elastic deformation is based on the constrained column model. Results show that, under the combined effect of entraining and squeeze-film actions throughout the walking cycle, the predicted central film thickness tends to decrease in the stance phase but keeps a relatively larger value at the swing phase. Furthermore, the geometry of knee joint implant is verified to play an important role under its lubrication condition, and the length of time period is a key point to influence the lubrication performance of joint components.

  7. Technical and economic analysis of replacing artificial lighting system to induction of photoperiod effect in begonia's seedlings in greenhouse Análise técnico-econômica da substituição do sistema de iluminação artificial para a indução do efeito de fotoperíodo na produção de mudas de begônias em ambiente protegido

    Directory of Open Access Journals (Sweden)

    Eduardo David

    2012-08-01

    Full Text Available The type of artificial light used for inducing photoperiod effect in begonia's seedlings at greenhouse has fundamental importance in the growth and development of these plants and directly reflects in the electrical energy consumption used in this production process. The objective of this research was to analyze the technical and economic feasibility of replacing the current technology of artificial lighting used by the producers (incandescent lamps, by the technology of discharge lamps with the purpose of inducing photoperiod in a greenhouse. The analysis results indicate that the discharge lamp of 32 W Tubular Fluorescent discharge lamp was the one that presented the lower peak demand and lower average energy consumption of 85.01% compared to incandescent filament lamp of 100 W that is the technology of bigger consumption and currently used by the producer.O tipo de iluminação artificial utilizado para a indução do efeito de fotoperíodo na produção de mudas de begônias em ambiente protegido tem fundamental importância no crescimento e no desenvolvimento destas plantas e reflete diretamente no consumo de energia elétrica utilizada no processo de produção. Objetiva-se com este trabalho analisar a viabilidade técnico-econômica de substituir-se a atual tecnologia de iluminação artificial utilizada pelos produtores (lâmpadas incandescentes pela tecnologia de lâmpadas de descarga para efeito de indução de fotoperíodo em ambiente protegido. Os resultados das análises indicam que a lâmpada de descarga Fluorescente Tubular de 32 W foi a que apresentou a menor demanda máxima de energia elétrica com redução média de consumo de 85,01% de energia em relação à lâmpada de filamento Incandescente de 100 W, que é a tecnologia atualmente utilizada pelo produtor, sem indução de floração.

  8. Shoulder replacement - discharge

    Science.gov (United States)

    Total shoulder arthroplasty - discharge; Endoprosthetic shoulder replacement - discharge; Partial shoulder replacement - discharge; Partial shoulder arthroplasty - discharge; Replacement - shoulder - discharge; Arthroplasty - shoulder - discharge

  9. Simultaneous Optimization of Block Replacement and Spare Part Ordering TIME for a Multi Component System with Separate Spare Part Ordering for Block and Failure Replacements

    OpenAIRE

    Mardin, Farid; Dekker, Rommert

    2016-01-01

    A block replacement schedule can be optimized simultaneously with a spare parts ordering schedule, since all items are replaced at a constant interval. The solution of joint optimization for spare parts ordering time and block replacement gives lower costs compared to separate optimization of ordering time and replacement time. The spare parts for replacement can be classified as stochastic demand for failure replacement and deterministic demand for block replacement. In this paper, we propos...

  10. Artificial intelligence

    International Nuclear Information System (INIS)

    Perret-Galix, D.

    1992-01-01

    A vivid example of the growing need for frontier physics experiments to make use of frontier technology is in the field of artificial intelligence and related themes. This was reflected in the second international workshop on 'Software Engineering, Artificial Intelligence and Expert Systems in High Energy and Nuclear Physics' which took place from 13-18 January at France Telecom's Agelonde site at La Londe des Maures, Provence. It was the second in a series, the first having been held at Lyon in 1990

  11. Artificial Intelligence

    CERN Document Server

    Warwick, Kevin

    2011-01-01

    if AI is outside your field, or you know something of the subject and would like to know more then Artificial Intelligence: The Basics is a brilliant primer.' - Nick Smith, Engineering and Technology Magazine November 2011 Artificial Intelligence: The Basics is a concise and cutting-edge introduction to the fast moving world of AI. The author Kevin Warwick, a pioneer in the field, examines issues of what it means to be man or machine and looks at advances in robotics which have blurred the boundaries. Topics covered include: how intelligence can be defined whether machines can 'think' sensory

  12. Artificial Intelligence.

    Science.gov (United States)

    Wash, Darrel Patrick

    1989-01-01

    Making a machine seem intelligent is not easy. As a consequence, demand has been rising for computer professionals skilled in artificial intelligence and is likely to continue to go up. These workers develop expert systems and solve the mysteries of machine vision, natural language processing, and neural networks. (Editor)

  13. IOL Implants: Lens Replacement and Cataract Surgery (Intraocular Lenses)

    Science.gov (United States)

    ... Cataract Surgery vs. Laser-Assisted Cataract Surgery Cataract Vision Simulator Cataract Pictures and Videos: What Do ... Mar. 27, 2018 An intraocular lens (or IOL) is a tiny, artificial lens for the eye. It replaces the eye's ...

  14. ERDA artificial heart program workshop. Final report, September 1, 1975--August 31, 1976

    International Nuclear Information System (INIS)

    Kantrowitz, A.; Altieri, F.; Beall, A.

    1976-08-01

    The major conclusions of the ERDA Artificial Heart Program Workshop are that the concept of a biologically compatible mechanical device which can totally replace the heart is sound, that such a device is needed as an alternative to cardiac transplantation and that its development is a realistic goal. The major recommendation of the committee is that an ERDA program with primary orientation toward development of a total heart replacement should continue, with assured funding about 50 percent higher than at present, for a minimum of 3 additional years at which time another major review should take place. To achieve better management of the program it is recommended that the present contract effort be reorganized under one prime contractor with responsibility for development and demonstration of the ERDA artificial heart system. The formation of a joint artificial heart advisory committee to improve coordination between ERDA and NHLI is also recommended. The committee suggests future policies and directions which it believes will lead to more effective use of funds available for specific aspects of the program. These include the nuclear heart source, engine, blood pump, biomaterials and overall system reliability. Possible future goals for the program are also proposed

  15. Artificial Intelligence.

    Science.gov (United States)

    Lawrence, David R; Palacios-González, César; Harris, John

    2016-04-01

    It seems natural to think that the same prudential and ethical reasons for mutual respect and tolerance that one has vis-à-vis other human persons would hold toward newly encountered paradigmatic but nonhuman biological persons. One also tends to think that they would have similar reasons for treating we humans as creatures that count morally in our own right. This line of thought transcends biological boundaries-namely, with regard to artificially (super)intelligent persons-but is this a safe assumption? The issue concerns ultimate moral significance: the significance possessed by human persons, persons from other planets, and hypothetical nonorganic persons in the form of artificial intelligence (AI). This article investigates why our possible relations to AI persons could be more complicated than they first might appear, given that they might possess a radically different nature to us, to the point that civilized or peaceful coexistence in a determinate geographical space could be impossible to achieve.

  16. of surfactant replacement therapy at Johannesburg Hospital ...

    African Journals Online (AJOL)

    Objective. To assess the impact of surfactant replacement therapy (SRl) on the outcome of hyaline membrane disease (HMD) and to assess the cost implications of a policy of selective administration of artificial surfactant. Design. The short-term outcome of 103 newborns ventilated for HMD (61 selected for SRT according to ...

  17. Artificial intelligence

    OpenAIRE

    Duda, Antonín

    2009-01-01

    Abstract : Issue of this work is to acquaint the reader with the history of artificial inteligence, esspecialy branch of chess computing. Main attention is given to progress from fifties to the present. The work also deals with fighting chess programs against each other, and against human opponents. The greatest attention is focused on 1997 and duel Garry Kasparov against chess program Deep Blue. The work is divided into chapters according to chronological order.

  18. Artificial Wormhole

    OpenAIRE

    Kirillov, A. A.; Savelova, E. P.

    2012-01-01

    It is shown that recently reported result by the OPERA Collaboration (arXive:1109.4897) of an early arrival time of muon neutrinos with respect to the speed of light in vacuum does not violate standard physical laws. We show that vacuum polarization effects in intensive external fields may form a wormhole-like object. The simplest theory of such an effect is presented and basic principles of formation of an artificial wormhole are also considered.

  19. Biomechanical Considerations in the Design of High-Flexion Total Knee Replacements

    Directory of Open Access Journals (Sweden)

    Cheng-Kung Cheng

    2014-01-01

    Full Text Available Typically, joint arthroplasty is performed to relieve pain and improve functionality in a diseased or damaged joint. Total knee arthroplasty (TKA involves replacing the entire knee joint, both femoral and tibial surfaces, with anatomically shaped artificial components in the hope of regaining normal joint function and permitting a full range of knee flexion. In spite of the design of the prosthesis itself, the degree of flexion attainable following TKA depends on a variety of factors, such as the joint’s preoperative condition/flexion, muscle strength, and surgical technique. High-flexion knee prostheses have been developed to accommodate movements that require greater flexion than typically achievable with conventional TKA; such high flexion is especially prevalent in Asian cultures. Recently, computational techniques have been widely used for evaluating the functionality of knee prostheses and for improving biomechanical performance. To offer a better understanding of the development and evaluation techniques currently available, this paper aims to review some of the latest trends in the simulation of high-flexion knee prostheses.

  20. Prosthesis of the wrist-joint

    Energy Technology Data Exchange (ETDEWEB)

    Feldmeier, C.

    1983-02-25

    Function of the hand-joint and the well-being of patients can be severely affected by arthrosis of the wrist-joint. Therapeutically, arthrodesis usually results in a painfree status of stiffness. A painless and well functioning joint can be achieved by alloplastic joint replacement or resurfacing. The possibilities and clinical results in cases of arthrosis of the carpo-metacarpal joint of the thumb, pseudarthrosis of the scaphoid, aseptic necrosis of the Lunate and severe arthrosis of the radio-carpal joint are demonstrated.

  1. Prosthesis of the wrist-joint

    International Nuclear Information System (INIS)

    Feldmeier, C.

    1983-01-01

    Function of the hand-joint and the well-being of patients can be severely affected by arthrosis of the wrist-joint. Therapeutically, arthrodesis usually results in a painfree status of stiffness. A painless and well functioning joint can be achieved by alloplastic joint replacement or resurfacing. The possibilities and clinical results in cases of arthrosis of the carpo-metacarpal joint of the thumb, pseudarthrosis of the scaphoid, aseptic necrosis of the Lunate and severe arthrosis of the radio-carpal joint are demonstrated. (orig.) [de

  2. Joint ventures

    DEFF Research Database (Denmark)

    Sørensen, Karsten Engsig

    Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret......Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret...

  3. From joint to single audits

    DEFF Research Database (Denmark)

    Holm, Claus; Thinggaard, Frank

    2018-01-01

    This study analyses audit quality differences between audits by a single big audit firm and joint audits with either one or two big audit firms. We exploit the unique situation in Denmark beginning on 1 January 2005, at which time a long-standing mandatory joint audit system for listed companies...... was replaced by a voluntary joint audit system. First, we report the results of a survey of Danish CFOs’ views on and their experiences with the choice of single or joint audits and their perceptions of audit quality. Second, based on data from the mandatory joint audit abolition year and the following two...... years, we test the audit quality differences using abnormal accruals. Most CFOs perceive that audit quality by a single big four audit firm is the same as it is in joint audits with either one or two big four audit firms. The results of our empirical analysis are in line with the perceptions. We find...

  4. 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...

  5. Exploring Artificial Intelligence Utilizing BioArt

    OpenAIRE

    Simou , Panagiota; Tiligadis , Konstantinos; Alexiou , Athanasios

    2013-01-01

    Part 15: First Workshop on Ethics and Philosophy in Artificial Intelligence (EPAI 2013); International audience; While artificial intelligence combined with Bioinformatics and Nanotechnology offers a variety of improvements and a technological and healthcare revolution, Bioartists attempt to replace the traditional artistic medium with biological materials, bio-imaging techniques, bioreactors and several times to treat their own body as an alive canvas. BioArt seems to play the role of a new ...

  6. ARTIFICIAL INTELLIGENCE- BENEFITS, CHALLENGES AND ETHICAL ISSUES

    OpenAIRE

    Elena Juganaru Andreou

    2017-01-01

    Nowadays, all big companies and most of small businesses are focused on increasing profitability and improving competitiveness. With this goal in mind, many of them turned to replace many tasks performed by humans with Artificial Intelligence. Artificial Intelligence (AI) is receiving an increasing attention lately and the debate is fiercely growing with a question not being answered yet: will it change the world for the better or for worse?

  7. Artificial graphites

    International Nuclear Information System (INIS)

    Maire, J.

    1984-01-01

    Artificial graphites are obtained by agglomeration of carbon powders with an organic binder, then by carbonisation at 1000 0 C and graphitization at 2800 0 C. After description of the processes and products, we show how the properties of the various materials lead to the various uses. Using graphite enables us to solve some problems, but it is not sufficient to satisfy all the need of the application. New carbonaceous material open application range. Finally, if some products are becoming obsolete, other ones are being developed in new applications [fr

  8. Nicotine replacement therapy

    Science.gov (United States)

    Smoking cessation - nicotine replacement; Tobacco - nicotine replacement therapy ... Before you start using a nicotine replacement product, here are some things to know: The more cigarettes you smoke, the higher the dose you may need to ...

  9. 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 ...

  10. Valve Repair or Replacement

    Science.gov (United States)

    ... Replacement Menu Topics Topics FAQs Valve Repair or Replacement Heart valves play a key role in this ... leaflets with a tissue patch. What is valve replacement? Severe valve damage means the valve must be ...

  11. Transcatheter aortic valve replacement

    Science.gov (United States)

    ... gov/ency/article/007684.htm Transcatheter aortic valve replacement To use the sharing features on this page, please enable JavaScript. Transcatheter aortic valve replacement (TAVR) is surgery to replace the aortic valve. ...

  12. Artificial rheotaxis.

    Science.gov (United States)

    Palacci, Jérémie; Sacanna, Stefano; Abramian, Anaïs; Barral, Jérémie; Hanson, Kasey; Grosberg, Alexander Y; Pine, David J; Chaikin, Paul M

    2015-05-01

    Motility is a basic feature of living microorganisms, and how it works is often determined by environmental cues. Recent efforts have focused on developing artificial systems that can mimic microorganisms, in particular their self-propulsion. We report on the design and characterization of synthetic self-propelled particles that migrate upstream, known as positive rheotaxis. This phenomenon results from a purely physical mechanism involving the interplay between the polarity of the particles and their alignment by a viscous torque. We show quantitative agreement between experimental data and a simple model of an overdamped Brownian pendulum. The model notably predicts the existence of a stagnation point in a diverging flow. We take advantage of this property to demonstrate that our active particles can sense and predictably organize in an imposed flow. Our colloidal system represents an important step toward the realization of biomimetic microsystems with the ability to sense and respond to environmental changes.

  13. Joint Commission

    Science.gov (United States)

    ... FAQs Universal Protocol Standards Quick Links E-dition - Electronic Standards Manuals Joint Commission Requirements Patient Safety Systems Chapter Measurement Measurement Performance Measurement Pioneers ...

  14. No evidence for the use of DIR, D-D fusions, chromosome 15 open reading frames or VH replacement in the peripheral repertoire was found on application of an improved algorithm, JointML, to 6329 human immunoglobulin H rearrangements

    DEFF Research Database (Denmark)

    Ohm-Laursen, Line; Nielsen, Morten; Larsen, Stine R

    2006-01-01

    Antibody diversity is created by imprecise joining of the variability (V), diversity (D) and joining (J) gene segments of the heavy and light chain loci. Analysis of rearrangements is complicated by somatic hypermutations and uncertainty concerning the sources of gene segments and the precise way...... in which they recombine. It has been suggested that D genes with irregular recombination signal sequences (DIR) and chromosome 15 open reading frames (OR15) can replace conventional D genes, that two D genes or inverted D genes may be used and that the repertoire can be further diversified by heavy chain V...

  15. Defining line replaceable units

    NARCIS (Netherlands)

    Parada Puig, J.E.; Basten, Robertus Johannes Ida

    2015-01-01

    Defective capital assets may be quickly restored to their operational condition by replacing the item that has failed. The item that is replaced is called the Line Replaceable Unit (LRU), and the so-called LRU definition problem is the problem of deciding on which item to replace upon each type of

  16. Inflatable artificial sphincter

    Science.gov (United States)

    ... procedures to treat urine leakage and incontinence include: Anterior vaginal wall repair Urethral bulking with artificial material ... urinary incontinence Images Inflatable artificial sphincter Anal sphincter anatomy Inflatable artificial sphincter - series References Adams MC, Joseph ...

  17. Artificial (Pu {sup 90}Sr, {sup 241}Am) and natural (U) isotopes in human bones from Poland

    Energy Technology Data Exchange (ETDEWEB)

    Mietelski, J.W.; Tomankiewicz, E. [Institute of Nuclear Phyics (Poland); Golec, E.; Golec, J.; Nowak, S.; Szczygiel, E. [The 5th Military Clinical Hospital and Polyclinic (Poland); Kuzma, K. [General Hospital (Poland)

    2014-07-01

    In two papers we have presented results if analyses of artificial isotopes ({sup 238,239,240}Pu, {sup 241}Am and {sup 90}Sr) content in human bones, using samples collected during hip joint replacement surgery. Since the patients were members of general population (not exposed in any particular form to artificial radionuclides) results can be treated as current background level for Poland and perhaps also whole central Europe. During this project the open question appeared - what is the level in human bones of natural alpha emitters like {sup 238}U-, {sup 234}U, for instance. Therefore about 30 human hip joint bone samples are being now analysed for the presence of uranium along with mentioned above artificial radionuclides. Samples are ashen and sequential radiochemical analyse is applied for separation of Pu, Sr and Am isotopes followed by separation of uranium using anion exchange resin. Measurements of plutonium, americium and uranium are performed using alpha spectrometry. That for {sup 90}Sr is done by LSC. Results will be presented during conference. Document available in abstract form only. (authors)

  18. Artificial versus Natural Intelligence: An Adendum to the Philosophy ...

    African Journals Online (AJOL)

    in modern science that is causing waves in the philosophy of mind. Can there be artificial minds? Can machines be made to think? Can machines be conscious? Is it possible for artificial intelligence to replace the human brain? These and similar questions pervade most discussions and philosophical polemics on the issue ...

  19. Temporomandibular joint

    International Nuclear Information System (INIS)

    Westesson, P.L.; Hatala, M.; Tallents, R.H.; Katzberg, R.W.; Musgrave, M.; Levitt, S.

    1990-01-01

    This paper determines the frequency of MR signs of abnormal temporomandibular joints (TMJs) in asymptomatic volunteers. Forty-two volunteers with 84 clinically normal TMJs were imaged in the sagittal and coronal planes with surface coil MR imaging. Sagittal closed and open and coronal closed views were obtained bilaterally in all volunteers. The images were classified as normal (superior disk position) or abnormal (disk displacement of degenerative joint disease). Eighteen joints in 11 volunteers were abnormal; 12 had disk displacement with reduction and six had disk displacement without reduction, with associated degenerative joint disease in three of the six. Asymptomatic internal derangement and degenerative joint disease occur in about one-fourth of asymptomatic volunteers

  20. Viability of pHEMA Hydrogels as Coating in Human Synovial Joint Prosthesis

    Directory of Open Access Journals (Sweden)

    V.P. Bavaresco

    2002-10-01

    Full Text Available In artificial joints, the bone part is usually substituted by a metallic component with high corrosion and strength resistance while the articular cartilage is replaced by a polymer. Use of thin layer of a compliant material acting as a bearing surface in human replacement joints has recently generated considerable interest. This work analyses the coating of a solid porous substrate of Ultra High Molecular Weight Polyethylene (UHMWPE with a poly (2-hydroxyethyl methacrylate (pHEMA and two sIPN-type blends: pHEMA-cellulose acetate butyrate (CAB and pHEMA-poly (ethyl methacrylate (PEM using 5.0% (w/w of the crosslinking agent and 11.0% (w/w of the linear reinforcing polymer. The wear resistance of the coating materials was evaluated in a TRI PIN ON DISK type equipment and the damage extension was characterized by Scanning Electron Microscopy (SEM. Preliminary qualitative tests were performed with the goal to identifying the hydrogels show the minimal required properties concerning wear strength. The pHEMA coating was completely destroyed during the first wear cycles, characterizing its low shear strength. By the other hand, after the complete experiment, both pHEMA-CAB and pHEMA-PEM blends showed a slightly improvement of abrasive and adhesive wear. This result indicates that the studied blends are promising materials to be used as compliant surfaces in joint prosthesis.

  1. Gait analysis after successful mobile bearing total ankle replacement.

    NARCIS (Netherlands)

    Doets, H.C.; van Middelkoop, M.; Houdijk, J.H.P.; Nelissen, R.G.; Veeger, H.E.J.

    2007-01-01

    Background: The effect of total ankle replacement on gait is not fully known in terms of joint kinematics, ground reaction force, and activity of the muscles of the lower leg. Methods: A comparative gait study was done in 10 patients after uneventful unilateral mobile-bearing total ankle replacement

  2. Outpatient Total Joint Arthroplasty.

    Science.gov (United States)

    Bert, Jack M; Hooper, Jessica; Moen, Sam

    2017-12-01

    Outpatient total joint arthroplasty (OTJA) allows for a safe, cost effective pathway for appropriately selected patients. With current pressures on arthroplasty surgeons and their associated institutions to reduce costs per episode of care, it is important to define the steps and challenges associated with establishing an outpatient arthroplasty program. Several studies have outlined techniques of selecting patients suitable for this type of postoperative pathway. With emerging concerns about patients who undergo outpatient arthroplasty being at increased risk of medical complications, which may lessen projected cost savings, it is important to identify value-based strategies to optimize patient recovery after OTJA. This article reviews digital techniques for patient selection and data collection, operating room efficiency systems, and provides a summary of methods to build and maintain value in outpatient total joint replacement within the framework of bundled payment reimbursement.

  3. The Joint Lessons Learned System and Interoperability

    Science.gov (United States)

    1989-06-02

    should not be artificially separated. 4 8 That lesson would not be learned here. Another lesson which was learned, however, was that interservice... artificially high level of support masked the continuing rivalry between the Army and Air Force over mission priorities. 6 4 In spite of Air Force...knowledge concerning joint interoperability issues and lessons learned activities. -72- MAP 2 Central African Republic Sudan sangu . Bo"oo Cameroon tuie

  4. Spine imaging after lumbar disc replacement: pitfalls and current recommendations

    Directory of Open Access Journals (Sweden)

    Sandén Bengt

    2009-07-01

    Full Text Available Abstract Background Most lumbar artificial discs are still composed of stainless steel alloys, which prevents adequate postoperative diagnostic imaging of the operated region when using magnetic resonance imaging (MRI. Thus patients with postoperative radicular symptoms or claudication after stainless steel implants often require alternative diagnostic procedures. Methods Possible complications of lumbar total disc replacement (TDR are reviewed from the available literature and imaging recommendations given with regard to implant type. Two illustrative cases are presented in figures. Results Access-related complications, infections, implant wear, loosening or fracture, polyethylene inlay dislodgement, facet joint hypertrophy, central stenosis, and ankylosis of the operated segment can be visualised both in titanium and stainless steel implants, but require different imaging modalities due to magnetic artifacts in MRI. Conclusion Alternative radiographic procedures should be considered when evaluating patients following TDR. Postoperative complications following lumbar TDR including spinal stenosis causing radiculopathy and implant loosening can be visualised by myelography and radionucleotide techniques as an adjunct to plain film radiographs. Even in the presence of massive stainless steel TDR implants lumbar radicular stenosis and implant loosening can be visualised if myelography and radionuclide techniques are applied.

  5. Replacing a Missing Tooth

    Science.gov (United States)

    ... there are two options for replacement: First, a removable partial denture may be used to replace the missing tooth. ... appearance look and feel more natural than a removable partial denture. However, it does require grinding down the support ...

  6. Elbow replacement - discharge

    Science.gov (United States)

    Total elbow arthroplasty - discharge; Endoprosthetic elbow replacement - discharge ... Pain is normal after elbow replacement surgery. It should get better over time. Your doctor will give you a prescription for pain medicine. Get it filled when ...

  7. Partial knee replacement - slideshow

    Science.gov (United States)

    ... medlineplus.gov/ency/presentations/100225.htm Partial knee replacement - series—Normal anatomy To use the sharing features ... M. Editorial team. Related MedlinePlus Health Topics Knee Replacement A.D.A.M., Inc. is accredited by ...

  8. Kidney Replacement Therapy

    Science.gov (United States)

    ... Size: A A A Listen En Español Kidney Replacement Therapy Diabetes sometimes damages kidneys so badly that ... Dialysis Dialysis, the more common form of kidney-replacement therapy, is a way of cleaning the blood ...

  9. 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 ...

  10. 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 ...

  11. Joint pain

    Science.gov (United States)

    ... or conditions. It may be linked to arthritis , bursitis , and muscle pain . No matter what causes it, ... Autoimmune diseases such as rheumatoid arthritis and lupus Bursitis Chondromalacia patellae Crystals in the joint: Gout (especially ...

  12. Cost-outcome analysis of joint replacement: evidence from a Spanish public hospital Análisis coste-resultado del remplazo de articulaciones: Evidencia de un hospital público español

    Directory of Open Access Journals (Sweden)

    José Luis Navarro Espigares

    2008-08-01

    Full Text Available Background and objectives: Efficiency-based healthcare decision-making has been widely accepted for some time, with cost per quality-adjusted life year (QALY as the main outcome measure. Nevertheless, for numerous medical procedures, little data are available on the cost per QALY gained. The aim of the present study was to calculate the cost per QALY gained with primary hip and knee replacement and to compare the result with the cost per QALY for other medical procedures, as well as with the maximum threshold cost considered acceptable in Spain. Methods: We performed a prospective cohort pre-test/post-test study of patients undergoing primary hip or knee arthroplasty. Age, sex, and clinical variables were recorded. Functional status and quality of life were measured by means of the WOMAC and EuroQol instruments, respectively, before the intervention and 6 months later. The direct costs of the intervention were calculated, with length of hospital stay and the prosthesis as the main cost drivers. Results: A total of 80 patients, 40 from each intervention, were included in this study. Both functional and perceived health status improved after the intervention. The number of QALYs gained in the knee cohort was 4.64, while that in the hip cohort was 0.86. The total cost of knee replacement was lower (6,865.52 € than that of hip replacement (7,891.21 €. The cost per QALY gained was 1,275.84 € and 7,936.12 € for knee and hip interventions, respectively. The calculations performed included a 6% discount rate for health outcomes, a 3% inflation rate for costs, and a success rate of 95% at 15 years. Conclusions: The costs of both knee and hip replacement were lower than the threshold of 30,000 € per QALY considered acceptable in Spain, and compared favorably with other medical and surgical procedures.Fundamento y objetivos: Está ampliamente aceptada la toma de decisiones sanitarias basada en la eficiencia, con el coste por año de vida ajustado

  13. Capital Equipment Replacement Decisions

    OpenAIRE

    Batterham, Robert L.; Fraser, K.I.

    1995-01-01

    This paper reviews the literature on the optimal replacement of capital equipment, especially farm machinery. It also considers the influence of taxation and capital rationing on replacement decisions. It concludes that special taxation provisions such as accelerated depreciation and investment allowances are unlikely to greatly influence farmers' capital equipment replacement decisions in Australia.

  14. Artificial Organs 2013: a year in review.

    Science.gov (United States)

    Malchesky, Paul S

    2014-03-01

    In this Editor's Review, articles published in 2013 are organized by category and briefly summarized. We aim to provide a brief reflection of the currently available worldwide knowledge that is intended to advance and better human life while providing insight for continued application of technologies and methods of organ Replacement, Recovery, and Regeneration. As the official journal of The International Federation for Artificial Organs, The International Faculty for Artificial Organs, the International Society for Rotary Blood Pumps, the International Society for Pediatric Mechanical Cardiopulmonary Support, and the Vienna International Workshop on Functional Electrical Stimulation, Artificial Organs continues in the original mission of its founders "to foster communications in the field of artificial organs on an international level". Artificial Organs continues to publish developments and clinical applications of artificial organ technologies in this broad and expanding field of organ Replacement, Recovery, and Regeneration from all over the world. We take this time also to express our gratitude to our authors for offering their work to this journal. We offer our very special thanks to our reviewers who give so generously of time and expertise to review, critique, and especially provide so meaningful suggestions to the author's work whether eventually accepted or rejected and especially to those whose native tongue is not English. Without these excellent and dedicated reviewers the quality expected from such a journal could not be possible. We also express our special thanks to our Publisher, Wiley Periodicals, for their expert attention and support in the production and marketing of Artificial Organs. We look forward to recording further advances in the coming years. © 2014 Wiley Periodicals, Inc. and International Center for Artificial Organs and Transplantation.

  15. The artificial kidney: past, present, and future.

    Science.gov (United States)

    Eknoyan, G

    2008-08-01

    World War II can be taken as a turning point after which the introduction and development of several new diagnostic and therapeutic discoveries have revolutionized medicine and improved the expectancy of life for millions. Notable amongst those technological therapeutic achievements is that of the artificial kidney, first used successfully in the closing years of the war. As a result of the improvements that followed, the kidney was the first solid organ whose function could be replaced, at least partially, by a machine. What started then as exploratory efforts to sustain life evolved over the next few decades into life saving replacement therapy for millions worldwide. Chronic maintenance hemodialysis has certainly changed the prognosis of the otherwise fatal end stage kidney disease that had afflicted humans theretofore. Unfortunately, many of the challenges and problems that had to be overcome in making artificial kidney treatment available continue to plague end-stage kidney disease patients on maintenance hemodialysis. Concerted investigative efforts are currently underway to improve the replacement of kidney function with artificial kidneys that better mimic kidney function. This article reviews the beginnings, evolution, and current challenges of the artificial kidney.

  16. Postoperative radiologic imaging of joint arthroplasty

    International Nuclear Information System (INIS)

    Aldinger, P.R.; Ludwig, K.

    2006-01-01

    With increased life expectancy in industrialised countries, improvement of implant design and operative technique, arthroplasty has become a routine procedure. The hip and knee joints are treated by arthroplasty most frequently. Nowadays joint replacement can be performed in many other joints. Radiologic imaging is an important tool for evaluation of the operative results and for detection of early and late complications. In the following article we describe the relevance of different imaging modalities as well as their systematic application in patients with joint arthroplasty. (orig.)

  17. Prosthetic elbow joint

    Science.gov (United States)

    Weddendorf, Bruce C. (Inventor)

    1994-01-01

    An artificial, manually positionable elbow joint for use in an upper extremity, above-elbow, prosthetic is described. The prosthesis provides a locking feature that is easily controlled by the wearer. The instant elbow joint is very strong and durable enough to withstand the repeated heavy loadings encountered by a wearer who works in an industrial, construction, farming, or similar environment. The elbow joint of the present invention comprises a turntable, a frame, a forearm, and a locking assembly. The frame generally includes a housing for the locking assembly and two protruding ears. The forearm includes an elongated beam having a cup-shaped cylindrical member at one end and a locking wheel having a plurality of holes along a circular arc on its other end with a central bore for pivotal attachment to the protruding ears of the frame. The locking assembly includes a collar having a central opening with a plurality of internal grooves, a plurality of internal cam members each having a chamfered surface at one end and a V-shaped slot at its other end; an elongated locking pin having a crown wheel with cam surfaces and locking lugs secured thereto; two coiled compression springs; and a flexible filament attached to one end of the elongated locking pin and extending from the locking assembly for extending and retracting the locking pin into the holes in the locking wheel to permit selective adjustment of the forearm relative to the frame. In use, the turntable is affixed to the upper arm part of the prosthetic in the conventional manner, and the cup-shaped cylindrical member on one end of the forearm is affixed to the forearm piece of the prosthetic in the conventional manner. The elbow joint is easily adjusted and locked between maximum flex and extended positions.

  18. Joint Intentionality

    Directory of Open Access Journals (Sweden)

    Koreň Ladislav

    2016-03-01

    Full Text Available According to the shared intentionality hypothesis proposed by Michael Tomasello, two cognitive upgrades – joint and collective intentionality, respectively – make human thinking unique. Joint intentionality, in particular, is a mindset supposed to account for our early, species-specific capacity to participate in collaborative activities involving two (or a few agents. In order to elucidate such activities and their proximate cognitive-motivational mechanism, Tomasello draws on philosophical accounts of shared intentionality. I argue that his deference to such cognitively demanding accounts of shared intentional activities is problematic if his theoretical ambition is in part to show that and how early (prelinguistic and precultural capacities for joint action contribute to the development of higher cognitive capacities.

  19. Trends in Artificial Intelligence.

    Science.gov (United States)

    Hayes, Patrick

    1978-01-01

    Discusses the foundations of artificial intelligence as a science and the types of answers that may be given to the question, "What is intelligence?" The paradigms of artificial intelligence and general systems theory are compared. (Author/VT)

  20. Artificial Hydration and Nutrition

    Science.gov (United States)

    ... Crisis Situations Pets and Animals myhealthfinder Food and Nutrition Healthy Food Choices Weight Loss and Diet Plans ... Your Health Resources Healthcare Management Artificial Hydration and Nutrition Artificial Hydration and Nutrition Share Print Patients who ...

  1. Joint imaging

    International Nuclear Information System (INIS)

    Hengst, W.

    1984-01-01

    Joint imaging is a proven diagnostic procedure which has become indispensable to the detection and treatment of different joint diseases in almost all disciplines. The method is suited for early diagnosis of joint affections both in soft tissue and bone which cannot be detected by X-ray or other procedures. The local activity accumulation depends on the rate of metabolism and is visualized in the scan, which in turn enables the extension and floridity of focal lesions to be evaluated and followed-up. Although joint scans may often give hints to probabilities relevant to differential diagnosis, the method is non-specific and only useful if based on the underlying clinical picture and X-ray finding, if possible. The radiation exposure is very low and does not represent a hazard in cases of adequate assessment of indication. In pregnant women and children the assessment of indication has to be based on very strict principles. The method is suited for out-patient diagnosis and can be applied in all installations equipped with a gamma camera and a technetium generator. (orig.) [de

  2. Joint purpose?

    DEFF Research Database (Denmark)

    Pristed Nielsen, Helene

    2013-01-01

    of anti-discrimination in Europe today? And what empirical evidence may be found for such a joint approach? The paper discusses how the contemporary EU context differs from the American context which prompted Crenshaw to raise the point about intersectionality, and it analyses documents and interviews...

  3. Aeronautical Information System Replacement -

    Data.gov (United States)

    Department of Transportation — Aeronautical Information System Replacement is a web-enabled, automation means for the collection and distribution of Service B messages, weather information, flight...

  4. Seeking optimal renal replacement therapy delivery in intensive care units.

    Science.gov (United States)

    Kocjan, Marinka; Brunet, Fabrice P

    2010-01-01

    Globally, critical care environments within health care organizations strive to provide optimal quality renal replacement therapy (RRT), an artificial replacement for lost kidney function. Examination of RRT delivery model literature and a case study review of the multidisciplinary-mixed RRT delivery model utilized within a closed medical surgical intensive care unit illustrates the organizational and clinical management of specialized resource and multidisciplinary roles. The successful utilization of a specific RRT delivery model is dependent upon resource availability.

  5. Artificial life and Piaget.

    Science.gov (United States)

    Mueller, Ulrich; Grobman, K H.

    2003-04-01

    Artificial life provides important theoretical and methodological tools for the investigation of Piaget's developmental theory. This new method uses artificial neural networks to simulate living phenomena in a computer. A recent study by Parisi and Schlesinger suggests that artificial life might reinvigorate the Piagetian framework. We contrast artificial life with traditional cognitivist approaches, discuss the role of innateness in development, and examine the relation between physiological and psychological explanations of intelligent behaviour.

  6. Design of a biped robot actuated by pneumatic artificial muscles.

    Science.gov (United States)

    Liu, Yixiang; Zang, Xizhe; Liu, Xinyu; Wang, Lin

    2015-01-01

    High compliant legs are essential for the efficient versatile locomotion and shock absorbency of humans. This study proposes a biped robot actuated by pneumatic artificial muscles to mimic human locomotion. On the basis of the musculoskeletal architecture of human lower limbs, each leg of the biped robot is modeled as a system of three segments, namely, hip joint, knee joint, and ankle joint, and eleven muscles, including both monoarticular and biarticular muscles. Each rotational joint is driven by a pair of antagonistic muscles, enabling joint compliance to be tuned by operating the pressure inside the muscles. Biarticular muscles play an important role in transferring power between joints. Walking simulations verify that biarticular muscles contribute to joint compliance and can absorb impact energy when the robot makes an impact upon ground contact.

  7. Options for Heart Valve Replacement

    Science.gov (United States)

    ... are the most commonly replaced valves. Pulmonary and tricuspid valve replacements are fairly uncommon in adults. Replacing a ... Problems and Causes • Risks, Signs and Symptoms • Accurate Diagnosis • Treatment Options ... Repair Valve Replacement - Ross Procedure - Newer Surgery Options - ...

  8. artificial neural network (ann)

    African Journals Online (AJOL)

    2004-08-18

    Aug 18, 2004 ... forecasting models and artificial intelligence techniques and have become one of the major research fields (Kher and Joshin, 2003). (a) Artificial Neural Network and Electrical Load. Prediction. Neural network analysis is an Artificial Intelligence. (AI) approach to mathematical modeling. Neural. Networks ...

  9. Radiation Source Replacement Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, Jeffrey W.; Moran, Traci L.; Bond, Leonard J.

    2010-12-01

    This report summarizes a Radiation Source Replacement Workshop in Houston Texas on October 27-28, 2010, which provided a forum for industry and researchers to exchange information and to discuss the issues relating to replacement of AmBe, and potentially other isotope sources used in well logging.

  10. CANDU-PHW fuel channel replacement experience

    International Nuclear Information System (INIS)

    Dunn, J.T.; Kakaria, B.K.

    1982-09-01

    One of the main characteristics of the CANDU pressurized heavy water reactor is the use of pressure tubes rather than one large pressure vessel to contain the fuel and coolant. This provides an inherent design capability to permit their replacement in an expeditious manner, without seriously affecting the high capacity factors of the reactor units. Of th eight Ontario Hydro commercial nuclear generating units, the lifetime performance places seven of them (including two that have had some of their fuel channels replaced), in the top ten positions in the world's large nuclear-electric unit performance ranking. Pressure tube cracks in the rolled joint region have resulted in 70 fuel channels being replaced in three reactor units, the latest being at the Bruce Nuclear Generating Station 'A', Unit 2 in February 1982. The rolled joint design and rolling procedures have been modified to eliminate this problem on CANDU units subsequent to Bruce 'A'. This paper describes the CANDU pressure tube performance history and expectations, and the tooling and procedures used to carry out the fuel channel replacement

  11. Leaving a joint audit system

    DEFF Research Database (Denmark)

    Holm, Claus; Thinggaard, Frank

    2014-01-01

    Purpose: The authors aim to exploit a natural experment in which voluntary replace mandatory joint audits for Danish listed companies and analyse audit fee implications of using one or two audit firms. Design/methodology/approach: Regression analysis is used. The authors apply both a core audit fee...... determinants model and an audit fee change model and include interaction terms. Findings: The authors find short-term fee reductions in companies switching to single audits, but only where the former joint audit contained a dominant auditor. The authors argue that in this situation bargaining power is more...... with the auditors than in a equally shared joint audit, and that the auditors' incentives to offer an initial fee discount are bigger. Research limitations/implications: The number of observations is constrained by the small Danish capital market. Future research could take a more qualitative research approach...

  12. Artificial Organs 2017: A Year in Review.

    Science.gov (United States)

    Malchesky, Paul S

    2018-03-01

    In this Editor's Review, articles published in 2017 are organized by category and summarized. We provide a brief reflection of the research and progress in artificial organs intended to advance and better human life while providing insight for continued application of these technologies and methods. Artificial Organs continues in the original mission of its founders "to foster communications in the field of artificial organs on an international level." Artificial Organs continues to publish developments and clinical applications of artificial organ technologies in this broad and expanding field of organ Replacement, Recovery, and Regeneration from all over the world. Peer-reviewed Special Issues this year included contributions from the 12th International Conference on Pediatric Mechanical Circulatory Support Systems and Pediatric Cardiopulmonary Perfusion edited by Dr. Akif Undar, Artificial Oxygen Carriers edited by Drs. Akira Kawaguchi and Jan Simoni, the 24th Congress of the International Society for Mechanical Circulatory Support edited by Dr. Toru Masuzawa, Challenges in the Field of Biomedical Devices: A Multidisciplinary Perspective edited by Dr. Vincenzo Piemonte and colleagues and Functional Electrical Stimulation edited by Dr. Winfried Mayr and colleagues. We take this time also to express our gratitude to our authors for offering their work to this journal. We offer our very special thanks to our reviewers who give so generously of time and expertise to review, critique, and especially provide meaningful suggestions to the author's work whether eventually accepted or rejected. Without these excellent and dedicated reviewers the quality expected from such a journal could not be possible. We also express our special thanks to our Publisher, John Wiley & Sons for their expert attention and support in the production and marketing of Artificial Organs. We look forward to reporting further advances in the coming years. © 2018 International Center for

  13. Spine imaging after lumbar disc replacement: pitfalls and current recommendations

    OpenAIRE

    Robinson, Yohan; Sand?n, Bengt

    2009-01-01

    Abstract Background Most lumbar artificial discs are still composed of stainless steel alloys, which prevents adequate postoperative diagnostic imaging of the operated region when using magnetic resonance imaging (MRI). Thus patients with postoperative radicular symptoms or claudication after stainless steel implants often require alternative diagnostic procedures. Methods Possible complications of lumbar total disc replacement (TDR) are reviewed from the available literature and imaging reco...

  14. The cost and effectiveness of surfactant replacement therapy at ...

    African Journals Online (AJOL)

    Objective. To assess the impact of surfactant replacement therapy (SRl) on the outcome of hyaline membrane disease (HMD) and to assess the cost implications of a policy of selective administration of artificial surfactant. Design. The short-term outcome of 103 newborns ventilated for HMD (61 selected for SRT according to ...

  15. The artificial leaf.

    Science.gov (United States)

    Nocera, Daniel G

    2012-05-15

    To convert the energy of sunlight into chemical energy, the leaf splits water via the photosynthetic process to produce molecular oxygen and hydrogen, which is in a form of separated protons and electrons. The primary steps of natural photosynthesis involve the absorption of sunlight and its conversion into spatially separated electron-hole pairs. The holes of this wireless current are captured by the oxygen evolving complex (OEC) of photosystem II (PSII) to oxidize water to oxygen. The electrons and protons produced as a byproduct of the OEC reaction are captured by ferrodoxin of photosystem I. With the aid of ferrodoxin-NADP(+) reductase, they are used to produce hydrogen in the form of NADPH. For a synthetic material to realize the solar energy conversion function of the leaf, the light-absorbing material must capture a solar photon to generate a wireless current that is harnessed by catalysts, which drive the four electron/hole fuel-forming water-splitting reaction under benign conditions and under 1 sun (100 mW/cm(2)) illumination. This Account describes the construction of an artificial leaf comprising earth-abundant elements by interfacing a triple junction, amorphous silicon photovoltaic with hydrogen- and oxygen-evolving catalysts made from a ternary alloy (NiMoZn) and a cobalt-phosphate cluster (Co-OEC), respectively. The latter captures the structural and functional attributes of the PSII-OEC. Similar to the PSII-OEC, the Co-OEC self-assembles upon oxidation of an earth-abundant metal ion from 2+ to 3+, may operate in natural water at room temperature, and is self-healing. The Co-OEC also activates H(2)O by a proton-coupled electron transfer mechanism in which the Co-OEC is increased by four hole equivalents akin to the S-state pumping of the Kok cycle of PSII. X-ray absorption spectroscopy studies have established that the Co-OEC is a structural relative of Mn(3)CaO(4)-Mn cubane of the PSII-OEC, where Co replaces Mn and the cubane is extended in a

  16. Could wind replace nuclear?

    International Nuclear Information System (INIS)

    2017-01-01

    This article aims at assessing the situation produced by a total replacement of nuclear energy by wind energy, while facing consumption demand at any moment, notably in December. The authors indicate the evolution of the French energy mix during December 2016, and the evolution of the rate between wind energy production and the sum of nuclear and wind energy production during the same month, and then give briefly some elements regarding necessary investments in wind energy to wholly replace nuclear energy. According to them, such a replacement would be ruinous

  17. REPLACEMENT OF PROXIMAL INTERPHALANGEAL JOINTS IN HAMMER TOE DEFORMITY

    Directory of Open Access Journals (Sweden)

    A. S. Petrosyan

    2012-01-01

    Full Text Available Objective: to assess the results of Hammertoe Implant Procedure (HIP in the treatment of hammer toes deformation. 28 operations were carried out in 16 patients aged 26 to 58 years with stage II-III (according to the classification of MI Kuslik of hammer toes from September 2009 to March 2011. In 50% of them surgeries were performed on one foot, in the second half - on two feet. Mean duration of follow-up was 12.4 months, range 6-21. Results: evaluation of the results was carried out by scale of AOFAS. A significant improvement was noted after HIP: in average score before surgery - 47, in the postoperative period - 92. In evaluating the average preoperative pain score was 24.3, postoperative - 36.0 (complete absence of pain is estimated to be 40 points. Improving the function of the foot with an average of 19 before surgery after surgery reached 41 points, while the position of the fingers (the alignment of the foot and toes is changed from the average value of 2.4 to 12.4 after surgery. Conclusion. Analysis of results showed the effectiveness of the HIP method in the treatment of hammertoe 2-3 fingers. HIP has allowed to achieve good functional and cosmetic results in early and the follow-up postoperative period. In our view, HIP with complex deformations forefoot can be used as an adjunct to other types of reconstructive surgery on the anterior part of the foot, and cases with recurrent strains hammer toes after surgery, HIP can be operation of choice.

  18. Structure modification of UHMWPE used for total joint replacements

    Czech Academy of Sciences Publication Activity Database

    Nevoralová, Martina; Baldrian, Josef; Pospíšil, Jan; Chodák, I.; Horák, Zdeněk

    74B, č. 2 (2005), s. 800-807 ISSN 1552-4973 R&D Projects: GA AV ČR IBS4050009 Institutional research plan: CEZ:AV0Z40500505 Keywords : UHMWPE * modification * gamma radiation Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.621, year: 2005

  19. Advances in Zirconia Toughened Alumina Biomaterials for Total Joint Replacement

    Science.gov (United States)

    Kurtz, Steven M.; Kocagöz, Sevi; Arnholt, Christina; Huet, Roland; Ueno, Masaru; Walter, William L.

    2014-01-01

    The objective of this article is to provide an up-to-date overview of zirconia-toughened alumina (ZTA) components used in total hip arthroplasties. The structure, mechanical properties, and available data regarding the clinical performance of ZTA are summarized. The advancements that have been made in understanding the in vivo performance of ZTA are investigated. This article concludes with a discussion of gaps in the literature related to ceramic biomaterials and avenues for future research. PMID:23746930

  20. Early Results of Total Hip·Joint Replacement

    African Journals Online (AJOL)

    1974-09-28

    Sep 28, 1974 ... If a series comprises only 2 grades, the figure after the decimal point indicates the per- centage in the higher group, e.g. with a series containing only 4s and Ss, an average of 4,7 indicates that 70% of cases are in grade 5. The greatest value of decimal frac- tions is with regard to the total range of movement ...

  1. Range of Motion Simulation of Hip Joint Movement During Salat Activity

    NARCIS (Netherlands)

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

    2017-01-01

    Background: Impingement of an artificial hip joint because of limited range of motion (RoM) during human activity is one of the main sources of hip joint failure. The aim of this article is to simulate the RoMs of hip joints during salat, the practice of formal worship in Islam. Methods: Salat

  2. Partial knee replacement

    Science.gov (United States)

    ... candidate for partial knee replacement and what the success rate is for your condition. Alternative Names Unicompartmental ... ADAM Health Solutions. About MedlinePlus Site Map FAQs Customer Support Get email updates Subscribe to RSS Follow ...

  3. Tool Inventory and Replacement

    Science.gov (United States)

    Bear, W. Forrest

    1976-01-01

    Vocational agriculture teachers are encouraged to evaluate curriculum offerings, the new trends in business and industry, and develop a master tool purchase and replacement plan over a 3- to 5-year period. (HD)

  4. Slab replacement maturity guidelines.

    Science.gov (United States)

    2014-04-01

    This study investigated the use of maturity method to determine early age strength of concrete in slab : replacement application. Specific objectives were (1) to evaluate effects of various factors on the compressive : maturity-strength relationship ...

  5. The replacement research reactor

    International Nuclear Information System (INIS)

    Cameron, R.

    1999-01-01

    As a consequences of the government decision in September 1997. ANSTO established a replacement research reactor project to manage the procurement of the replacement reactor through the necessary approval, tendering and contract management stages This paper provides an update of the status of the project including the completion of the Environmental Impact Statement. Prequalification and Public Works Committee processes. The aims of the project, management organisation, reactor type and expected capabilities are also described

  6. 21 CFR 872.3940 - Total temporomandibular joint prosthesis.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3940 Total temporomandibular joint... implanted in the human jaw to replace the mandibular condyle and augment the glenoid fossa to functionally...

  7. Artificial Intelligence in Astronomy

    Science.gov (United States)

    Devinney, E. J.; Prša, A.; Guinan, E. F.; Degeorge, M.

    2010-12-01

    From the perspective (and bias) as Eclipsing Binary researchers, we give a brief overview of the development of Artificial Intelligence (AI) applications, describe major application areas of AI in astronomy, and illustrate the power of an AI approach in an application developed under the EBAI (Eclipsing Binaries via Artificial Intelligence) project, which employs Artificial Neural Network technology for estimating light curve solution parameters of eclipsing binary systems.

  8. Quo Vadis, Artificial Intelligence?

    OpenAIRE

    Berrar, Daniel; Sato, Naoyuki; Schuster, Alfons

    2010-01-01

    Since its conception in the mid 1950s, artificial intelligence with its great ambition to understand and emulate intelligence in natural and artificial environments alike is now a truly multidisciplinary field that reaches out and is inspired by a great diversity of other fields. Rapid advances in research and technology in various fields have created environments into which artificial intelligence could embed itself naturally and comfortably. Neuroscience with its desire to understand nervou...

  9. Artificial cognition architectures

    CERN Document Server

    Crowder, James A; Friess, Shelli A

    2013-01-01

    The goal of this book is to establish the foundation, principles, theory, and concepts that are the backbone of real, autonomous Artificial Intelligence. Presented here are some basic human intelligence concepts framed for Artificial Intelligence systems. These include concepts like Metacognition and Metamemory, along with architectural constructs for Artificial Intelligence versions of human brain functions like the prefrontal cortex. Also presented are possible hardware and software architectures that lend themselves to learning, reasoning, and self-evolution

  10. Multicompartment Artificial Organelles Conducting Enzymatic Cascade Reactions inside Cells

    DEFF Research Database (Denmark)

    Gallardo, Maria Godoy; Labay, Cédric Pierre; Trikalitis, Vasileios

    2017-01-01

    Cell organelles are subcellular structures entrapping a set of enzymes to achieve a specific functionality. The incorporation of artificial organelles into cells is a novel medical paradigm which might contribute to the treatment of various cell disorders by replacing malfunctioning organelles....... In particular, artificial organelles are expected to be a powerful solution in the context of enzyme replacement therapy since enzymatic malfunction is the primary cause of organelle dysfunction. Although several attempts have been made to encapsulate enzymes within a carrier vehicle, only few intracellularly...

  11. An artificial muscle computer

    Science.gov (United States)

    Marc O'Brien, Benjamin; Alexander Anderson, Iain

    2013-03-01

    We have built an artificial muscle computer based on Wolfram's "2, 3" Turing machine architecture, the simplest known universal Turing machine. Our computer uses artificial muscles for its instruction set, output buffers, and memory write and addressing mechanisms. The computer is very slow and large (0.15 Hz, ˜1 m3); however by using only 13 artificial muscle relays, it is capable of solving any computable problem given sufficient memory, time, and reliability. The development of this computer shows that artificial muscles can think—paving the way for soft robots with reflexes like those seen in nature.

  12. Meniscus tear surgery and meniscus replacement

    Science.gov (United States)

    Vaquero, Javier; Forriol, Francisco

    2016-01-01

    Summary Objective the menisci are easily injured and difficult to repair. The aim of this study was to analyze the current state of meniscal surgery aimed at preserving morphology and conserving the biomechanics of the knee to prevent joint degeneration. Methodology a search of the electronic medical literature database Medline was conducted, from http://www.ncbi.nlm.nih.gov/pubmed. The search was not limited by language. Candidate articles were identified by searching for those that included the keywords meniscus, surgery, suture, implant, allograft. The limits were included for clinical research and clinical trials. Basic research was not included. The studies selected were evaluated and classified in three different categories: basic science, reconstruction (suture and meniscectomy) and implants (scaffolds and allograft). Results the consequences of meniscectomy performed at a young age can lead to a joint cartilage degeneration twenty years later. There are few surgical options for the repair of meniscal injuries in order both to preserve the meniscus and to ensure the long term survival of the knee joint, meniscectomy, repair, suturing the tear, or reconstruction, when a meniscal allograft or synthetic substitute is used to replace the meniscus, but the biomechanical properties of the native meniscus are not reproduced entirely by the scaffolds that exist today. Conclusion therapies that successfully repair or replace the meniscus are therefore likely to prevent or delay osteoarthritis progression. PMID:27331034

  13. Degenerative Joint Diseases and Neuroinflammation.

    Science.gov (United States)

    Fusco, Mariella; Skaper, Stephen D; Coaccioli, Stefano; Varrassi, Giustino; Paladini, Antonella

    2017-04-01

    Rheumatic and joint diseases, as exemplified by osteoarthritis and rheumatoid arthritis, are among the most widespread painful and disabling pathologies across the globe. Given the continuing rise in life expectancy, their prevalence is destined to grow. Osteoarthritis, a degenerative joint disease, is, in particular, on its way to becoming the fourth leading cause of disability worldwide by 2020, with the rising incidence of obesity in addition to age being important factors. It is estimated that 25% of osteoarthritic individuals are unable to perform daily activities. Accompanying osteoarthritis is rheumatoid arthritis, which is a chronic systemic disease that often causes pain and deformity. At least 50% of those affected are unable to remain gainfully employed within 10 years of disease onset. A growing body of evidence now points to inflammation, locally and more systemically, as a promoter of damage to joints and bones, as well as joint-related functional deficits. The pathogenesis underlying joint diseases remains unclear; however, it is currently believed that cross-talk between cartilage and subchondral bone-and loss of balance between these two structures in joint diseases-is a critical element. This view is amplified by the presence of mast cells, whose dysregulation is associated with alterations of junction structures (cartilage, bone, synovia, matrix, nerve endings, and blood vessels). In addition, persistent activation of mast cells facilitates the development of spinal neuroinflammation mediated through their interaction with microglia. Unfortunately, current treatment strategies for rheumatic and articular disease are symptomatic and do little to limit disease progression. Research now should be directed at therapeutic modalities that target osteoarticular structural elements and thereby delaying disease progression and joint replacement. © 2016 World Institute of Pain.

  14. Kinematic Analysis of 2-DOF Planer Robot Using Artificial Neural Network

    OpenAIRE

    Jolly Shah; S.S.Rattan; B.C.Nakra

    2011-01-01

    Automatic control of the robotic manipulator involves study of kinematics and dynamics as a major issue. This paper involves the forward and inverse kinematics of 2-DOF robotic manipulator with revolute joints. In this study the Denavit- Hartenberg (D-H) model is used to model robot links and joints. Also forward and inverse kinematics solution has been achieved using Artificial Neural Networks for 2-DOF robotic manipulator. It shows that by using artificial neural networ...

  15. Artificial life and life artificialization in Tron

    Directory of Open Access Journals (Sweden)

    Carolina Dantas Figueiredo

    2012-12-01

    Full Text Available Cinema constantly shows the struggle between the men and artificial intelligences. Fiction, and more specifically fiction films, lends itself to explore possibilities asking “what if?”. “What if”, in this case, is related to the eventual rebellion of artificial intelligences, theme explored in the movies Tron (1982 and Tron Legacy (2010 trat portray the conflict between programs and users. The present paper examines these films, observing particularly the possibility programs empowering. Finally, is briefly mentioned the concept of cyborg as a possibility of response to human concerns.

  16. Artificial Organs 2016: A Year in Review.

    Science.gov (United States)

    Hadsell, Angela T; Malchesky, Paul S

    2017-03-01

    In this Editor's Review, articles published in 2016 are organized by category and briefly summarized. We aim to provide a brief reflection of the currently available worldwide knowledge that is intended to advance and better human life while providing insight for continued application of technologies and methods of organ Replacement, Recovery, and Regeneration. As the official journal of The International Federation for Artificial Organs, The International Faculty for Artificial Organs, the International Society for Mechanical Circulatory Support, the International Society for Pediatric Mechanical Cardiopulmonary Support, and the Vienna International Workshop on Functional Electrical Stimulation, Artificial Organs continues in the original mission of its founders "to foster communications in the field of artificial organs on an international level." Artificial Organs continues to publish developments and clinical applications of artificial organ technologies in this broad and expanding field of organ Replacement, Recovery, and Regeneration from all over the world. We were pleased to publish our second Virtual Issue in April 2016 on "Tissue Engineering in Bone" by Professor Tsuyoshi Takato. Our first was published in 2011 titled "Intra-Aortic Balloon Pumping" by Dr. Ashraf Khir. Other peer-reviewed Special Issues this year included contributions from the 11th International Conference on Pediatric Mechanical Circulatory Support Systems and Pediatric Cardiopulmonary Perfusion edited by Dr. Akif Ündar and selections from the 23rd Congress of the International Society for Rotary Blood Pumps edited by Dr. Bojan Biocina. We take this time also to express our gratitude to our authors for offering their work to this journal. We offer our very special thanks to our reviewers who give so generously of time and expertise to review, critique, and especially provide meaningful suggestions to the author's work whether eventually accepted or rejected. Without these excellent and

  17. Product Platform Replacements

    DEFF Research Database (Denmark)

    Sköld, Martin; Karlsson, Christer

    2012-01-01

    . To shed light on this unexplored and growing managerial concern, the purpose of this explorative study is to identify operational challenges to management when product platforms are replaced. Design/methodology/approach – The study uses a longitudinal field-study approach. Two companies, Gamma and Omega......Purpose – It is argued in this article that too little is known about product platforms and how to deal with them from a manager's point of view. Specifically, little information exists regarding when old established platforms are replaced by new generations in R&D and production environments...... distinguishing between platform replacement “height” and “width”. Seven groups of managerial measures for dealing with the issues are recommended. Originality/value – The study aims to contribute to the existing literature by taking a managers' perspective of product platform development. Its specific...

  18. Artificial insemination in poultry

    Science.gov (United States)

    Artificial insemination is a relative simple yet powerful tool geneticists can employ for the propagation of economically important traits in livestock and poultry. In this chapter, we address the fundamental methods of the artificial insemination of poultry, including semen collection, semen evalu...

  19. Wormhole Formation in RSRM Nozzle Joint Backfill

    Science.gov (United States)

    Stevens, J.

    2000-01-01

    The RSRM nozzle uses a barrier of RTV rubber upstream of the nozzle O-ring seals. Post flight inspection of the RSRM nozzle continues to reveal occurrence of "wormholes" into the RTV backfill. The term "wormholes", sometimes called "gas paths", indicates a gas flow path not caused by pre-existing voids, but by a little-understood internal failure mode of the material during motor operation. Fundamental understanding of the mechanics of the RSRM nozzle joints during motor operation, nonlinear viscoelastic characterization of the RTV backfill material, identification of the conditions that predispose the RTV to form wormholes, and screening of candidate replacement materials is being pursued by a joint effort between Thiokol Propulsion, NASA, and the Army Propulsion & Structures Directorate at Redstone Arsenal. The performance of the RTV backfill in the joint is controlled by the joint environment. Joint movement, which applies a tension and shear load on the material, coupled with the introduction of high pressure gas in combination create an environment that exceeds the capability of the material to withstand the wormhole effect. Little data exists to evaluate why the material fails under the modeled joint conditions, so an effort to characterize and evaluate the material under these conditions was undertaken. Viscoelastic property data from characterization testing will anchor structural analysis models. Data over a range of temperatures, environmental pressures, and strain rates was used to develop a nonlinear viscoelastic model to predict material performance, develop criteria for replacement materials, and quantify material properties influencing wormhole growth. Three joint simulation analogs were developed to analyze and validate joint thermal barrier (backfill) material performance. Two exploratory tests focus on detection of wormhole failure under specific motor operating conditions. A "validation" test system provides data to "validate" computer models and

  20. Antibiotic Prophylaxis During Dental Procedures in Patients with Prosthetic Joints

    Science.gov (United States)

    Sendi, Parham; Uçkay, Ilker; Suvà, Domizio; Vogt, Markus; Borens, Olivier; Clauss, Martin

    2016-01-01

    In patients with artificial joints, the need for antimicrobial prophylaxis during dental procedures is often raised. The present document describes the pathogenic mechanisms and epidemiological data on the subject of periprosthetic joint infections (PJI) after dental procedures. The document reflects the opinion and recommendations of the expert group 'Infection' of Swiss Orthopaedics. Microorganisms belonging to oral flora can seed haematogenously to an artificial joint. The proof of a causative relation with dental procedures is not possible, because the responsible bacteraemia can originate from the oral cavity at any time, irrespective of when the dental procedure occurs. Good oral hygiene is associated with a lower risk for PJI. Transient bacteraemia occurs during daily oral hygiene activity (e.g., tooth brushing) and thus the cumulative risk for a haematogenous PJI from tooth brushing is higher than that from a dental procedure. PJI after a dental procedure are rarely reported. On the basis of an epidemiological model, several thousand patients with artificial joints must receive antimicrobial prophylaxis to prevent a single PJI. Considering this ratio, the number of adverse events due to the antimicrobial compound exceeds the benefit of administering it by a large magnitude. Therefore, as a rule for the vast majority of cases, antimicrobial prophylaxis during dental procedures is not recommended. It is important that a patient has a good oral health status before joint implantation and that good oral hygiene is continuously maintained in patients with artificial joints. PMID:28529852

  1. Artificial organs 2014: a year in review.

    Science.gov (United States)

    Malchesky, Paul S

    2015-03-01

    In this Editor's Review, articles published in 2014 are organized by category and briefly summarized. We aim to provide a brief reflection of the currently available worldwide knowledge that is intended to advance and better human life while providing insight for continued application of technologies and methods of organ Replacement, Recovery, and Regeneration. As the official journal of the International Federation for Artificial Organs, the International Faculty for Artificial Organs, the International Society for Rotary Blood Pumps, the International Society for Pediatric Mechanical Cardiopulmonary Support, and the Vienna International Workshop on Functional Electrical Stimulation, Artificial Organs continues in the original mission of its founders "to foster communications in the field of artificial organs on an international level." Artificial Organs continues to publish developments and clinical applications of artificial organ technologies in this broad and expanding field of organ Replacement, Recovery, and Regeneration from all over the world. We take this time also to express our gratitude to our authors for offering their work to this journal. We offer our very special thanks to our reviewers who give so generously of time and expertise to review, critique, and especially provide meaningful suggestions to the author's work whether eventually accepted or rejected. Without these excellent and dedicated reviewers, the quality expected from such a journal could not be possible. We also express our special thanks to our Publisher, John Wiley & Sons, for their expert attention and support in the production and marketing of Artificial Organs. We look forward to reporting further advances in the coming years. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  2. Cervical intervertebral disc replacement.

    Science.gov (United States)

    Cason, Garrick W; Herkowitz, Harry N

    2013-02-06

    Symptomatic adjacent-level disease after cervical fusion has led to the development and testing of several disc-replacement prostheses. Randomized controlled trials of cervical disc replacement (CDR) compared with anterior cervical discectomy and fusion (ACDF) have demonstrated at least equivalent clinical results for CDR with similar or lower complication rates. Biomechanical, kinematic, and radiographic studies of CDR reveal that the surgical level and adjacent vertebral level motion and center of rotation more closely mimic the native state. Lower intradiscal pressures adjacent to CDR may help decrease the incidence of adjacent spinal-level disease, but long-term follow-up is necessary to evaluate this theory.

  3. Reliability of Tubular Joints

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    In this paper the preliminary results obtained by tests on tubular joints are presented. The joints are T-joints and the loading is static. It is the intention in continuation of these tests to perform tests on other types of joints (e.g. Y-joints) and also with dynamic loading. The purpose of th...

  4. Prioritizing equipment for replacement.

    Science.gov (United States)

    Capuano, Mike

    2010-01-01

    It is suggested that clinical engineers take the lead in formulating evaluation processes to recommend equipment replacement. Their skill, knowledge, and experience, combined with access to equipment databases, make them a logical choice. Based on ideas from Fennigkoh's scheme, elements such as age, vendor support, accumulated maintenance cost, and function/risk were used.6 Other more subjective criteria such as cost benefits and efficacy of newer technology were not used. The element of downtime was also omitted due to the data element not being available. The resulting Periop Master Equipment List and its rationale was presented to the Perioperative Services Program Council. They deemed the criteria to be robust and provided overwhelming acceptance of the list. It was quickly put to use to estimate required capital funding, justify items already thought to need replacement, and identify high-priority ranked items for replacement. Incorporating prioritization criteria into an existing equipment database would be ideal. Some commercially available systems do have the basic elements of this. Maintaining replacement data can be labor-intensive regardless of the method used. There is usually little time to perform the tasks necessary for prioritizing equipment. However, where appropriate, a clinical engineering department might be able to conduct such an exercise as shown in the following case study.

  5. Can photovoltaic replace nuclear?

    International Nuclear Information System (INIS)

    2017-01-01

    As the French law on energy transition for a green growth predicts that one third of nuclear energy production is to be replaced by renewable energies (wind and solar) by 2025, and while the ADEME proposes a 100 per cent renewable scenario for 2050, this paper proposes a brief analysis of the replacement of nuclear energy by solar photovoltaic energy. It presents and discusses some characteristics of photovoltaic production: production level during a typical day for each month (a noticeable lower production in December), evolution of monthly production during a year, evolution of the rate between nuclear and photovoltaic production. A cost assessment is then proposed for energy storage and for energy production, and a minimum cost of replacement of nuclear by photovoltaic is assessed. The seasonal effect is outlined, as well as the latitude effect. Finally, the authors outline the huge cost of such a replacement, and consider that public support to new photovoltaic installations without an at least daily storage mean should be cancelled

  6. Thyroid hormone replacement therapy

    NARCIS (Netherlands)

    Wiersinga, W. M.

    2001-01-01

    Thyroid hormone replacement has been used for more than 100 years in the treatment of hypothyroidism, and there is no doubt about its overall efficacy. Desiccated thyroid contains both thyroxine (T(4)) and triiodothyronine (T(3)); serum T(3) frequently rises to supranormal values in the absorption

  7. Replacing Recipe Realism

    OpenAIRE

    Saatsi, J

    2017-01-01

    Many realist writings exemplify the spirit of ‘recipe realism’. Here I characterise recipe realism, challenge it, and propose replacing it with ‘exemplar realism’. This alternative understanding of realism is more piecemeal, robust, and better in tune with scientists’ own attitude towards their best theories, and thus to be preferred.

  8. Apixaban or enoxaparin for thromboprophylaxis after knee replacement

    DEFF Research Database (Denmark)

    Lassen, Michael Rud; Raskob, Gary E; Gallus, Alexander

    2009-01-01

    BACKGROUND: The optimal strategy for thromboprophylaxis after major joint replacement has not been established. Low-molecular-weight heparins such as enoxaparin predominantly target factor Xa but to some extent also inhibit thrombin. Apixaban, a specific factor Xa inhibitor, may provide effective...

  9. Total hip replacement surgery in Ethiopia | Gokcen | East and ...

    African Journals Online (AJOL)

    Background: Total hip replacement (THR) surgery has evolved over years to the point that it has been considered as "the operation of the century". For developed countries, arthroplasty is well established for the management of various joint disorders and has completely revolutionised the treatment of the arthritic hip.

  10. Total hip replacements at Kikuyu Hospital, Kenya | Kingori | East ...

    African Journals Online (AJOL)

    Background: Total joint arthroplasty is a highly effective procedure that is frequently performed in elderly patients. This is not so in the third world and is not frequently performed. Total hip replacement (THR) relieves the pain and functional disability experienced by patients with moderate to severe arthritis of the hip, ...

  11. STRESS ANALYSIS OF THE RADIAL HEAD REPLACEMENTS IN AN ELBOW ARTICULATION

    Czech Academy of Sciences Publication Activity Database

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

    2008-01-01

    Roč. 15, č. 5 (2008), s. 319-327 ISSN 1802-1484 Institutional research plan: CEZ:AV0Z20760514 Keywords : elbow joint * elbow articulation * radial head replacement * computational modelling Subject RIV: BO - Biophysics

  12. Elbow prosthesis (image)

    Science.gov (United States)

    Elbow replacement involves surgically replacing bones that make up the elbow joint with artificial elbow joint parts (prosthetic components). The artificial joint consists of two stems made of high-quality metal. They are joined together ...

  13. Joint Instability and Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Darryl Blalock

    2015-01-01

    Full Text Available Joint instability creates a clinical and economic burden in the health care system. Injuries and disorders that directly damage the joint structure or lead to joint instability are highly associated with osteoarthritis (OA. Thus, understanding the physiology of joint stability and the mechanisms of joint instability-induced OA is of clinical significance. The first section of this review discusses the structure and function of major joint tissues, including periarticular muscles, which play a significant role in joint stability. Because the knee, ankle, and shoulder joints demonstrate a high incidence of ligament injury and joint instability, the second section summarizes the mechanisms of ligament injury-associated joint instability of these joints. The final section highlights the recent advances in the understanding of the mechanical and biological mechanisms of joint instability-induced OA. These advances may lead to new opportunities for clinical intervention in the prevention and early treatment of OA.

  14. Joint Advanced Warfighting School

    National Research Council Canada - National Science Library

    Davis, Jon

    2003-01-01

    When the United States employs military power, it does so as a joint force. The cornerstone for effective joint force employment remains Service competency, but truly effective Service warfighters must think, plan and fight jointly...

  15. Artificial intelligence in medicine.

    Science.gov (United States)

    Ramesh, A N; Kambhampati, C; Monson, J R T; Drew, P J

    2004-09-01

    Artificial intelligence is a branch of computer science capable of analysing complex medical data. Their potential to exploit meaningful relationship with in a data set can be used in the diagnosis, treatment and predicting outcome in many clinical scenarios. Medline and internet searches were carried out using the keywords 'artificial intelligence' and 'neural networks (computer)'. Further references were obtained by cross-referencing from key articles. An overview of different artificial intelligent techniques is presented in this paper along with the review of important clinical applications. The proficiency of artificial intelligent techniques has been explored in almost every field of medicine. Artificial neural network was the most commonly used analytical tool whilst other artificial intelligent techniques such as fuzzy expert systems, evolutionary computation and hybrid intelligent systems have all been used in different clinical settings. Artificial intelligence techniques have the potential to be applied in almost every field of medicine. There is need for further clinical trials which are appropriately designed before these emergent techniques find application in the real clinical setting.

  16. Artificial intelligence in medicine.

    Science.gov (United States)

    Ramesh, A. N.; Kambhampati, C.; Monson, J. R. T.; Drew, P. J.

    2004-01-01

    INTRODUCTION: Artificial intelligence is a branch of computer science capable of analysing complex medical data. Their potential to exploit meaningful relationship with in a data set can be used in the diagnosis, treatment and predicting outcome in many clinical scenarios. METHODS: Medline and internet searches were carried out using the keywords 'artificial intelligence' and 'neural networks (computer)'. Further references were obtained by cross-referencing from key articles. An overview of different artificial intelligent techniques is presented in this paper along with the review of important clinical applications. RESULTS: The proficiency of artificial intelligent techniques has been explored in almost every field of medicine. Artificial neural network was the most commonly used analytical tool whilst other artificial intelligent techniques such as fuzzy expert systems, evolutionary computation and hybrid intelligent systems have all been used in different clinical settings. DISCUSSION: Artificial intelligence techniques have the potential to be applied in almost every field of medicine. There is need for further clinical trials which are appropriately designed before these emergent techniques find application in the real clinical setting. PMID:15333167

  17. Quo Vadis, Artificial Intelligence?

    Directory of Open Access Journals (Sweden)

    Daniel Berrar

    2010-01-01

    Full Text Available Since its conception in the mid 1950s, artificial intelligence with its great ambition to understand and emulate intelligence in natural and artificial environments alike is now a truly multidisciplinary field that reaches out and is inspired by a great diversity of other fields. Rapid advances in research and technology in various fields have created environments into which artificial intelligence could embed itself naturally and comfortably. Neuroscience with its desire to understand nervous systems of biological organisms and systems biology with its longing to comprehend, holistically, the multitude of complex interactions in biological systems are two such fields. They target ideals artificial intelligence has dreamt about for a long time including the computer simulation of an entire biological brain or the creation of new life forms from manipulations of cellular and genetic information in the laboratory. The scope for artificial intelligence in neuroscience and systems biology is extremely wide. This article investigates the standing of artificial intelligence in relation to neuroscience and systems biology and provides an outlook at new and exciting challenges for artificial intelligence in these fields. These challenges include, but are not necessarily limited to, the ability to learn from other projects and to be inventive, to understand the potential and exploit novel computing paradigms and environments, to specify and adhere to stringent standards and robust statistical frameworks, to be integrative, and to embrace openness principles.

  18. New artificial fluoro-cofactor of hydride transfer with novel fluorescence assay for redox biocatalysis.

    Science.gov (United States)

    Zhang, Lei; Yuan, Jun; Xu, Yufang; Zhang, Y-H Percival; Qian, Xuhong

    2016-05-11

    A new artificial fluoro-cofactor was developed for the replacement of natural cofactors NAD(P), exhibiting a high hydride transfer ability. More importantly, we established a new and fast screening method for the evaluation of the properties of artificial cofactors based on the fluorescence assay and visible color change.

  19. [Application status of rapid prototyping technology in artificial bone based on reverse engineering].

    Science.gov (United States)

    Fang, Ao; Zheng, Min; Fan, Ding

    2015-02-01

    Artificial bone replacement has made an important contribution to safeguard human health and improve the quality of life. The application requirements of rapid prototyping technology based on reverse engineering in individualized artificial bone with individual differences are particularly urgent. This paper reviewed the current research and applications of rapid prototyping and reverse engineering in artificial bone. The research developments and the outlook of bone kinematics and dynamics simulation are also introduced.

  20. Electronic hidden solder joint geometry characterization

    Science.gov (United States)

    Hsieh, Sheng-Jen

    2009-05-01

    To reduce the size of electronic equipment, multi-layer printed circuit board structures have become popular in recent years. As a result, the inspection of hidden solder joints between layers of boards has become increasingly difficult. Xray machines have been used for ball grid array (BGA) and hidden solder joint inspection; however, the equipment is costly and the inspection process is time consuming. In this paper, we investigate an active thermography approach to probing solder joint geometry. A set of boards having the same number of solder joints and amount of solder paste (0.061 g) was fabricated. Each solder joint had a different geometry. A semi-automated system was built to heat and then transfer each board to a chamber where an infrared camera was used to scan the board as it was cooling down. Two-thirds of the data set was used for model development and one-third was used for model evaluation. Both artificial neural network (ANN) and binary logistic regression models were constructed. Results suggest that solder joints with more surface area cool much faster than those with less surface area. In addition, both modeling approaches are consistent in predicting solder geometry; ANN had 85% accuracy and the regression model had 80%. This approach can potentially be used to test for cold solder joints prior to BGA assembly, since cold solder joints may have air gaps between the joint and the board and air is a poor heat conductor. Therefore, a cold solder joint may have a slower cooling rate than a normal one.

  1. Development and Physical Control Research on Prototype Artificial Leg

    Directory of Open Access Journals (Sweden)

    Fei Li

    2016-03-01

    Full Text Available To provide an ideal platform for research on intelligent bionic leg (IBL, this paper proposes a model of a biped robot with heterogeneous legs (BRHL. A prototype of an artificial leg is developed based on biological structure and motion principle analysis of human lower extremities. With regard to the driving sources, servomotors are chosen for the hip joint and ankle joint, while pneumatic muscle actuators (PMAs are chosen for the knee joint. The control system of the bionic artificial leg is designed and a physical experimental platform is established. The physical control experiments are done based on proportional-integral-derivative (PID control strategy. The experimental results show that such a system can realize the expected goals.

  2. Intelligence: Real or artificial?

    Science.gov (United States)

    Schlinger, Henry D.

    1992-01-01

    Throughout the history of the artificial intelligence movement, researchers have strived to create computers that could simulate general human intelligence. This paper argues that workers in artificial intelligence have failed to achieve this goal because they adopted the wrong model of human behavior and intelligence, namely a cognitive essentialist model with origins in the traditional philosophies of natural intelligence. An analysis of the word “intelligence” suggests that it originally referred to behavior-environment relations and not to inferred internal structures and processes. It is concluded that if workers in artificial intelligence are to succeed in their general goal, then they must design machines that are adaptive, that is, that can learn. Thus, artificial intelligence researchers must discard their essentialist model of natural intelligence and adopt a selectionist model instead. Such a strategic change should lead them to the science of behavior analysis. PMID:22477051

  3. Aortic valve replacement

    DEFF Research Database (Denmark)

    Kapetanakis, Emmanouil I; Athanasiou, Thanos; Mestres, Carlos A

    2008-01-01

    BACKGROUND AND AIMS OF THE STUDY: Prompted by anecdotal evidence and observations by surgeons, an investigation was undertaken into the potential differences in implanted aortic valve prosthesis sizes, during aortic valve replacement (AVR) procedures, between northern and southern European...... assigned to the 'small' aortic size subset. Effective orifice area indices were calculated for all patients to assess the geographic distribution of patient-prosthesis mismatch. Univariable and multivariable logistic regression analyses adjusting for possible confounding variables were performed. RESULTS...

  4. The replacement research reactor

    International Nuclear Information System (INIS)

    Cameron, R.; Horlock, K.

    2001-01-01

    The contract for the design, construction and commissioning of the Replacement Research Reactor was signed in July 2000. This was followed by the completion of the detailed design and an application for a construction licence was made in May 2001. This paper will describe the main elements of the design and their relation to the proposed applications of the reactor. The future stages in the project leading to full operation are also described

  5. Nonlinear joint angle control for artificially stimulated muscle

    NARCIS (Netherlands)

    Veltink, Petrus H.; Chizeck, Howard J.; Crago, Patrick E.; El-Bialy, Ahmed

    1992-01-01

    Designs of both open- and closed-loop controllers of electrically stimulated muscle that explicitly depend on a nonlinear mathematical model of muscle input-output properties are presented and evaluated. The muscle model consists of three factors: a muscle activation dynamics factor, an angle-torque

  6. UCI knee replacement.

    Science.gov (United States)

    Evanski, P M; Waugh, T R; Orofino, C F; Anzel, S H

    1976-10-01

    Between March 9, 1972 and December 31, 1973, a total of 103 UCI knee replacements were performed. Follow-up data are available on 83 knees with an average follow-up of 33 months. Patient evaluation of the end results indicates that 78.3 per cent were better, 9.6 per cent unchanged, and 12.1 per cent worse. Patient evaluation of their own knee function averaged 55 per cent preoperatively and 79 per cent postoperatively. Patients were also evaluated on a 100 point Modified Larson Analysis Form. The average preoperative score was 46, and the average postoperative score was 70. There were six (5.8%) biological complications in the 103 knee replacement. Biological complications included infections, wound healing problems and unexplained pain. Mechanical complications were seen in 18 (17.4%) knees, and included knee instability, tibial component loosening or deformation, and patellar problems. Additional surgery was required in 18 (17.4%) knees. Failure of the procedure eventually requiring removal of the prosthesis and fusion or amputation occurred in 4 (3.9%) knees. The intermediate-term results of UCI knee replacement have been clinically satisfactory. We currently recommend consideration of this procedure for patients with disabling arthritis of the knee.

  7. Principles of artificial intelligence

    CERN Document Server

    Nilsson, Nils J

    1980-01-01

    A classic introduction to artificial intelligence intended to bridge the gap between theory and practice, Principles of Artificial Intelligence describes fundamental AI ideas that underlie applications such as natural language processing, automatic programming, robotics, machine vision, automatic theorem proving, and intelligent data retrieval. Rather than focusing on the subject matter of the applications, the book is organized around general computational concepts involving the kinds of data structures used, the types of operations performed on the data structures, and the properties of th

  8. Artificial intelligence in cardiology

    OpenAIRE

    Bonderman, Diana

    2017-01-01

    Summary Decision-making is complex in modern medicine and should ideally be based on available data, structured knowledge and proper interpretation in the context of an individual patient. Automated algorithms, also termed artificial intelligence that are able to extract meaningful patterns from data collections and build decisions upon identified patterns may be useful assistants in clinical decision-making processes. In this article, artificial intelligence-based studies in clinical cardiol...

  9. Artificial intelligence in medicine.

    OpenAIRE

    Ramesh, A. N.; Kambhampati, C.; Monson, J. R. T.; Drew, P. J.

    2004-01-01

    INTRODUCTION: Artificial intelligence is a branch of computer science capable of analysing complex medical data. Their potential to exploit meaningful relationship with in a data set can be used in the diagnosis, treatment and predicting outcome in many clinical scenarios. METHODS: Medline and internet searches were carried out using the keywords 'artificial intelligence' and 'neural networks (computer)'. Further references were obtained by cross-referencing from key articles. An overview of ...

  10. Intelligence: Real or artificial?

    OpenAIRE

    Schlinger, Henry D.

    1992-01-01

    Throughout the history of the artificial intelligence movement, researchers have strived to create computers that could simulate general human intelligence. This paper argues that workers in artificial intelligence have failed to achieve this goal because they adopted the wrong model of human behavior and intelligence, namely a cognitive essentialist model with origins in the traditional philosophies of natural intelligence. An analysis of the word “intelligence” suggests that it originally r...

  11. Nuclear-powered artificial heart system

    International Nuclear Information System (INIS)

    Pouchot, W.D.; Lehrfeld, D.

    1976-01-01

    As reported to the 9th IECEC, a bench model version of a nuclear-powered artificial heart system to be used as a replacement for the natural heart was constructed and tested as part of a broader U.S. ERDA program. A report is given of the system design and integration, bench testing, and field support equipment of an implantable and advanced version of the bench model incorporating some of the component developments reported to the 10th IECEC. The basic elements of the system are a 32-watt Pu-238 heat source, a Stirling engine thermal converter, a coupling mechanism, and a mechanical blood pump drive actuating, alternatively, two artificial ventricles of polymeric material. As tested on the bench using a mock circulation, the system provides approximately 9 liters/minute at 120/80 mm Hg aortic pressure. At 190/145 mm Hg aortic pressure, the maximum flow decreases to about 7 liters/minute

  12. Emergence by Design in Artificial Spin Ice

    Science.gov (United States)

    Nisoli, Cristiano; Morrison, Muir; Chern, Gia-Wei; Gilbert, Ian; Zhang, Sheng; Schiffer, Peter

    2015-03-01

    Recently a new perspective has opened in the study of frustration through the creation of artificial frustrated magnetic systems. These materials consist of arrays of lithographically fabricated single-domain ferromagnetic nanostructures that behave like giant Ising spins, whose interactions can be controlled through appropriate choices of their geometric properties and arrangement on a (frustrated) lattice. Higher control, inclusive of genuine thermal ensembles have replaced the earlier and coarser methods based on magnetic agitation. Dynamical versions are now being realized, characterized in real time via PEEM, revealing statistical mechanics in action. This affords implementation of new geometries, not found in nature, for dedicated bottom up design of desired emergent properties. Born as a scientific toy to investigate frustration-by-design, artificial spin ice might now be used to open ``a path into an uncharted territory, a landscape of advanced functional materials in which topological effects on physical properties can be explored and harnessed.''.

  13. 21 CFR 888.3800 - Wrist joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3800 Section 888.3800 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Wrist joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. A wrist joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a wrist joint...

  14. 21 CFR 888.3110 - Ankle joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ankle joint metal/polymer semi-constrained... Ankle joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An ankle joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an ankle...

  15. ROBERT autonomous navigation robot with artificial vision

    International Nuclear Information System (INIS)

    Cipollini, A.; Meo, G.B.; Nanni, V.; Rossi, L.; Taraglio, S.; Ferjancic, C.

    1993-01-01

    This work, a joint research between ENEA (the Italian National Agency for Energy, New Technologies and the Environment) and DIGlTAL, presents the layout of the ROBERT project, ROBot with Environmental Recognizing Tools, under development in ENEA laboratories. This project aims at the development of an autonomous mobile vehicle able to navigate in a known indoor environment through the use of artificial vision. The general architecture of the robot is shown together with the data and control flow among the various subsystems. Also the inner structure of the latter complete with the functionalities are given in detail

  16. International joint ventures

    DEFF Research Database (Denmark)

    Sørensen, Karsten Engsig

    2001-01-01

    The article analysis problems connected with corporate joint ventures. Among others the possible conflicts between the joint venture agreement and the statutes of the companies is examined, as well as certain problems connected to the fact that the joint venture partners have created commen control...... over their joint company....

  17. The wearable artificial kidney: is peritoneal dialysis the solution?

    Science.gov (United States)

    Ronco, Claudio

    2009-01-01

    The evolution of technology in hemodialysis has a new challenge in the development of miniaturization, transportability and wearability of devices applicable for renal replacement therapy. Although we are not there yet, a new series of papers have recently been published showing promising results on the application of a wearable artificial kidney. Some of them use extracorporeal blood cleansing as a method of blood purification while others use peritoneal dialysis as a treatment modality. Many of the challenges imposed by an extracorporeal wearable artificial kidney can be overcome by the use of the PD technique in a wearable system. A PD-based wearable artificial kidney has been demonstrated to be feasible and potentially applicable in chronic patients. We should make an effort to make a quantum leap in technology making the wearable artificial kidney a reality rather than a dream.

  18. Artificial exomuscle investigations for applications-metal hydride

    International Nuclear Information System (INIS)

    Crevier, Marie-Charlotte; Richard, Martin; Rittenhouse, D Matheson; Roy, Pierre-Olivier; Bedard, Stephane

    2007-01-01

    In pursuing the development of bionic devices, Victhom identified a need for technologies that could replace current motorized systems and be better integrated into the human body motion. The actuators used to obtain large displacements are noisy, heavy, and do not adequately reproduce human muscle behavior. Subsequently, a project at Victhom was devoted to the development of active materials to obtain an artificial exomuscle actuator. An exhaustive literature review was done at Victhom to identify promising active materials for the development of artificial muscles. According to this review, metal hydrides were identified as a promising technology for artificial muscle development. Victhom's investigations focused on determining metal hydride actuator potential in the context of bionics technology. Based on metal hydride properties and artificial muscle requirements such as force, displacement and rise time, an exomuscle was built. In addition, a finite element model, including heat and mass transfer in the metal hydride, was developed and implemented in FEMLAB software. (review article)

  19. Artificial Gravity Research Project

    Science.gov (United States)

    Kamman, Michelle R.; Paloski, William H.

    2005-01-01

    Protecting the health, safety, and performance of exploration-class mission crews against the physiological deconditioning resulting from long-term weightlessness during transit and long-term hypogravity during surface operations will require effective, multi-system countermeasures. Artificial gravity (AG), which would replace terrestrial gravity with inertial forces generated by rotating the transit vehicle or by a human centrifuge device within the transit vehicle or surface habitat, has long been considered a potential solution. However, despite its attractiveness as an efficient, multi-system countermeasure and its potential for improving the environment and simplifying operational activities (e.g., WCS, galley, etc.), much still needs to be learned regarding the human response to rotating environments before AG can be successfully implemented. This paper will describe our approach for developing and implementing a rigorous AG Research Project to address the key biomedical research questions that must be answered before developing effective AG countermeasure implementation strategies for exploration-class missions. The AG Research Project will be performed at JSC, ARC, extramural academic and government research venues, and international partner facilities maintained by DLR and IMBP. The Project includes three major ground-based human research subprojects that will lead to flight testing of intermittent short-radius AG in ISS crewmembers after 201 0, continuous long-radius AG in CEV crews transiting to and from the Moon, and intermittent short-radius AG plus exercise in lunar habitats. These human ground-based subprojects include: 1) a directed, managed international short-radius project to investigate the multi-system effectiveness of intermittent AG in human subjects deconditioned by bed rest, 2) a directed, managed long-radius project to investigate the capacity of humans to live and work for extended periods in rotating environments, and 3) a focused

  20. Cognitive dysfunction after fast-track hip and knee replacement

    DEFF Research Database (Denmark)

    Krenk, Lene; Kehlet, Henrik; Bæk Hansen, Torben

    2014-01-01

    , and the pathogenic mechanisms are still unclear. We evaluated a large uniform cohort of elderly patients in a standardized approach, after major joint replacement surgery (total hip and knee replacement). Patients were in an optimized perioperative approach (fast track) with multimodal opioid-sparing analgesia......, early mobilization, and short length of stay (LOS ≤3 days) and discharged to home. METHODS: In a prospective multicenter study, we included 225 patients aged ≥60 years undergoing well-defined fast-track total hip or total knee replacement. Patients had neuropsychological testing preoperatively and 1...... this (23.6% of patients with early POCD had late onset vs 6.7% in non-POCD group; risk difference 16.9 (95% CI, -2.1% to 41.1%; P = 0.089). CONCLUSIONS: The incidence of POCD early after total hip and knee replacement seems to be lower after a fast-track approach than rates previously reported...

  1. Installation technology of reactor internals on shroud replacement work

    International Nuclear Information System (INIS)

    Miyano, Hiroshi

    1999-01-01

    Since the replacement of large welded reactor internals much as a core shroud did not have a precedent in the world, quite a few technologies had to be developed. Especially for the installation of new core shroud, jet pumps, core plate and top guide, the accurate weld and fit-up techniques for large structures was required to secure their integrity. The vessel shielding system was utilized to reduce general area dose rate such that all replacement work. For jet pump installation, automatic remote welding machines were used for high radiation area. As for the core shroud, shroud support weld prep machining tool with high accuracy, jacking system to support fit-up, new weld machine for small work space and low heat input weld joint were developed. Shroud replacement work in Fukushima Dai-ichi NPS Unit 3 (1F-3) with application of these development techniques, was successfully accomplished. The technology is applied for 1F-2 replacement work also. (author)

  2. REPLACEMENT OF FRENCH CARDS

    CERN Multimedia

    Human Resources Division

    2001-01-01

    The French Ministry of Foreign Affairs has informed the Organization that it is shortly to replace all diplomatic cards, special cards and employment permits ('attestations de fonctions') now held by members of the personnel and their families. Between 2 July and 31 December 2001, these cards are to be replaced by secure, computerized equivalents. A 'personnel office' stamped photocopy of the old cards may continue to be used until 31 December 2001. For the purposes of the handover, members of the personnel must go personally to the cards office (33/1-015), between 8:30 and 12:30, in order to fill a 'fiche individuelle' form (in black ink only), which has to be personally signed by themselves and another separately signed by members of their family, taking the following documents for themselves and members of their families already in possession of a French card : A recent identity photograph in 4.5 cm x 3.5 cm format (signed on the back) The French card in their possession an A4 photocopy of the same Fre...

  3. Total disc replacement.

    Science.gov (United States)

    Vital, J-M; Boissière, L

    2014-02-01

    Total disc replacement (TDR) (partial disc replacement will not be described) has been used in the lumbar spine since the 1980s, and more recently in the cervical spine. Although the biomechanical concepts are the same and both are inserted through an anterior approach, lumbar TDR is conventionally indicated for chronic low back pain, whereas cervical TDR is used for soft discal hernia resulting in cervicobrachial neuralgia. The insertion technique must be rigorous, with precise centering in the disc space, taking account of vascular anatomy, which is more complex in the lumbar region, particularly proximally to L5-S1. All of the numerous studies, including prospective randomized comparative trials, have demonstrated non-inferiority to fusion, or even short-term superiority regarding speed of improvement. The main implant-related complication is bridging heterotopic ossification with resulting loss of range of motion and increased rates of adjacent segment degeneration, although with an incidence lower than after arthrodesis. A sufficiently long follow-up, which has not yet been reached, will be necessary to establish definitively an advantage for TDR, particularly in the cervical spine. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  4. Cadmium plating replacements

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, M.J.; Groshart, E.C.

    1995-03-01

    The Boeing Company has been searching for replacements to cadmium plate. Two alloy plating systems seem close to meeting the needs of a cadmium replacement. The two alloys, zinc-nickel and tin-zinc are from alloy plating baths; both baths are neutral pH. The alloys meet the requirements for salt fog corrosion resistance, and both alloys excel as a paint base. Currently, tests are being performed on standard fasteners to compare zinc-nickel and tin-zinc on threaded hardware where cadmium is heavily used. The Hydrogen embrittlement propensity of the zinc-nickel bath has been tested, and just beginning for the tin-zinc bath. Another area of interest is the electrical properties on aluminum for tin-zinc and will be discussed. The zinc-nickel alloy plating bath is in production in Boeing Commercial Airplane Group for non-critical low strength steels. The outlook is promising that these two coatings will help The Boeing Company significantly reduce its dependence on cadmium plating.

  5. Power Plant Replacement Study

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Gary

    2010-09-30

    This report represents the final report for the Eastern Illinois University power plant replacement study. It contains all related documentation from consideration of possible solutions to the final recommended option. Included are the economic justifications associated with the chosen solution along with application for environmental permitting for the selected project for construction. This final report will summarize the results of execution of an EPC (energy performance contract) investment grade audit (IGA) which lead to an energy services agreement (ESA). The project includes scope of work to design and install energy conservation measures which are guaranteed by the contractor to be self-funding over its twenty year contract duration. The cost recovery is derived from systems performance improvements leading to energy savings. The prime focus of this EPC effort is to provide a replacement solution for Eastern Illinois University’s aging and failing circa 1925 central steam production plant. Twenty-three ECMs were considered viable whose net impact will provide sufficient savings to successfully support the overall project objectives.

  6. REPLACEMENT OF FRENCH CARDS

    CERN Document Server

    HR/SOC

    2001-01-01

    The French Ministry of Foreign Affairs has informed the Organization that it is shortly to replace all diplomatic cards, special cards and employment permits ('attestations de fonctions') now held by members of the personnel and their families. Between 2 July and 31 December 2001, these cards are to be replaced by secure, computerized equivalents. The old cards may continue to be used until 31 December 2001. For the purposes of the handover, members of the personnel must go personally to the cards office (33/1-015), in order to fill in a 'fiche individuelle' form, taking the following documents for themselves and members of their families already in possession of a French card : A recent identity photograph in 4.5 cm x 3.5 cm format. The French card in their possession. An A4 photocopy of the same French card, certified by the cards office as being a true copy. Those members of the personnel whose cards (and/or cards belonging to members of their families) are shortly due to expire, or have recently done...

  7. REPLACEMENT OF FRENCH CARDS

    CERN Document Server

    Human Resources Division; Cards.Service@cern.ch

    2001-01-01

    The French Ministry of Foreign Affairs is currently replacing all diplomatic cards, special cards and employment permits («attestations de fonctions») held by members of the personnel and their families. These cards are replaced by secure, computerized equivalents. The old cards may no longer be used after 31 December 2001. For the purposes of the handover, members of the personnel must go personally to the cards office (33/1-015) between 8h30 and 12h30, in order to fill in a «fiche individuelle» form, taking the following documents for themselves and members of their families already in possession of a French card : A recent identity photograph in 4.5 cm x 3.5 cm format, the French card in their possession, an A4 photocopy of the same French card, certified by the cards office as being a true copy. Those members of the personnel whose cards (and/or cards belonging to members of their families) are shortly due to expire, or have recently done so, are also requested...

  8. REPLACEMENT OF FRENCH CARDS

    CERN Multimedia

    Human Resources Division

    2001-01-01

    The French Ministry of Foreign Affairs has informed the Organization that it is shortly to replace all diplomatic cards, special cards and employment permits ('attestations de fonctions') now held by members of the personnel and their families. Between 2 July and 31 December 2001, these cards are to be replaced by secure, computerized equivalents. The old cards may continue to be used until 31 December 2001. For the purposes of the handover, members of the personnel are asked to go to the cards office (33/1-015), taking the following documents for themselves and members of their families already in possession of a French card : A recent identity photograph in 4.5 cm x 3.5 cm format, The French card in their possession, an A4 photocopy of the same French card, certified by the cards office as being a true copy. Those members of the personnel whose cards (and/or cards belonging to members of their families) are shortly due to expire, or have recently done so, are also requested to take these items to the c...

  9. Temporomandibular Joint Reconstruction in the Growing Child.

    Science.gov (United States)

    Resnick, Cory M

    2018-02-01

    Indications and considerations for reconstruction of the temporomandibular joint (TMJ) differ between growing and skeletally mature patients. Osteoarthritis, which is the most common cause of TMJ destruction in adults, is comparatively rare in children. The most common indications in young patients are congenital deformities, pathology, ankylosis and progressive resorptive processes. Options for reconstruction include distraction osteogenesis, autologous reconstruction (ie, costochondral graft, free fibula flap), and total alloplastic joint replacement. The choice of the ideal reconstruction is based on multiple factors, which include extent and laterality of the deformity, patient age, jaw growth pattern, and potential for progressive destruction. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Artificial intelligence in nanotechnology

    International Nuclear Information System (INIS)

    Sacha, G M; Varona, P

    2013-01-01

    During the last decade there has been increasing use of artificial intelligence tools in nanotechnology research. In this paper we review some of these efforts in the context of interpreting scanning probe microscopy, the study of biological nanosystems, the classification of material properties at the nanoscale, theoretical approaches and simulations in nanoscience, and generally in the design of nanodevices. Current trends and future perspectives in the development of nanocomputing hardware that can boost artificial-intelligence-based applications are also discussed. Convergence between artificial intelligence and nanotechnology can shape the path for many technological developments in the field of information sciences that will rely on new computer architectures and data representations, hybrid technologies that use biological entities and nanotechnological devices, bioengineering, neuroscience and a large variety of related disciplines. (topical review)

  11. Artificial organ engineering

    CERN Document Server

    Annesini, Maria Cristina; Piemonte, Vincenzo; Turchetti, Luca

    2017-01-01

    Artificial organs may be considered as small-scale process plants, in which heat, mass and momentum transfer operations and, possibly, chemical transformations are carried out. This book proposes a novel analysis of artificial organs based on the typical bottom-up approach used in process engineering. Starting from a description of the fundamental physico-chemical phenomena involved in the process, the whole system is rebuilt as an interconnected ensemble of elemental unit operations. Each artificial organ is presented with a short introduction provided by expert clinicians. Devices commonly used in clinical practice are reviewed and their performance is assessed and compared by using a mathematical model based approach. Whilst mathematical modelling is a fundamental tool for quantitative descriptions of clinical devices, models are kept simple to remain focused on the essential features of each process. Postgraduate students and researchers in the field of chemical and biomedical engineering will find that t...

  12. Artificial intelligence in nanotechnology.

    Science.gov (United States)

    Sacha, G M; Varona, P

    2013-11-15

    During the last decade there has been increasing use of artificial intelligence tools in nanotechnology research. In this paper we review some of these efforts in the context of interpreting scanning probe microscopy, the study of biological nanosystems, the classification of material properties at the nanoscale, theoretical approaches and simulations in nanoscience, and generally in the design of nanodevices. Current trends and future perspectives in the development of nanocomputing hardware that can boost artificial-intelligence-based applications are also discussed. Convergence between artificial intelligence and nanotechnology can shape the path for many technological developments in the field of information sciences that will rely on new computer architectures and data representations, hybrid technologies that use biological entities and nanotechnological devices, bioengineering, neuroscience and a large variety of related disciplines.

  13. Diseases of the joints

    International Nuclear Information System (INIS)

    Rogers, L.F.

    1987-01-01

    Radiographs are used in diseases of the joints to confirm the clinical diagnosis of joint disease, determine the type of joint disease, and evaluate the extent of clinically known disease. The radiographic findings may be either consistent or inconsistent with the clinical diagnosis. If inconsistent, an alternative diagnosis should be made on the basis of the radiographic appearance of the disease process. On other occasions, joint disease is observed on a radiograph obtained for some other reason, such as for peripheral trauma; on a chest radiograph demonstrating changes in the spine or pectoral girdle; or on radiographs of the abdomen and pelvis revealing abnormalities of the spine, sacroiliac joints, or hips. In the latter situations, the joint disease should be categorized and included in the radiographic report. There are four principal radiographic signs of joint abnormalities or joint disease. These are (1) abnormalities of the apposing margins of both bones at a joint, (2) change in the width of the joint space, usually narrowing, but occasionally, widening due to an increase in synovial fluid, (3) malalignment of the joint (subluxation or dislocation with the joint margins no longer in apposition), and (4) periarticular swelling due to distension of the joint capsule. The most common findings are narrowing of the joint space and abnormalities of the apposing articular margins of bone

  14. [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.

  15. Artificial intelligence in cardiology.

    Science.gov (United States)

    Bonderman, Diana

    2017-12-01

    Decision-making is complex in modern medicine and should ideally be based on available data, structured knowledge and proper interpretation in the context of an individual patient. Automated algorithms, also termed artificial intelligence that are able to extract meaningful patterns from data collections and build decisions upon identified patterns may be useful assistants in clinical decision-making processes. In this article, artificial intelligence-based studies in clinical cardiology are reviewed. The text also touches on the ethical issues and speculates on the future roles of automated algorithms versus clinicians in cardiology and medicine in general.

  16. Artificial intelligence executive summary

    International Nuclear Information System (INIS)

    Wamsley, S.J.; Purvis, E.E. III

    1984-01-01

    Artificial intelligence (AI) is a high technology field that can be used to provide problem solving diagnosis, guidance and for support resolution of problems. It is not a stand alone discipline, but can also be applied to develop data bases for retention of the expertise that is required for its own knowledge base. This provides a way to retain knowledge that otherwise may be lost. Artificial Intelligence Methodology can provide an automated construction management decision support system, thereby restoring the manager's emphasis to project management

  17. Bayesian artificial intelligence

    CERN Document Server

    Korb, Kevin B

    2003-01-01

    As the power of Bayesian techniques has become more fully realized, the field of artificial intelligence has embraced Bayesian methodology and integrated it to the point where an introduction to Bayesian techniques is now a core course in many computer science programs. Unlike other books on the subject, Bayesian Artificial Intelligence keeps mathematical detail to a minimum and covers a broad range of topics. The authors integrate all of Bayesian net technology and learning Bayesian net technology and apply them both to knowledge engineering. They emphasize understanding and intuition but also provide the algorithms and technical background needed for applications. Software, exercises, and solutions are available on the authors' website.

  18. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has...... made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction...

  19. Improving artificial breeding of cattle and buffalo in Asia. Guidelines and recommendations. A manual prepared under the framework of an IAEA Technical Cooperation Regional RCA Project on 'Improving Animal Productivity and Reproductive Efficiency', with technical support of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture

    International Nuclear Information System (INIS)

    2005-11-01

    The International Atomic Energy Agency (IAEA) and the Regional Cooperative Agreement for Asia and the Pacific Region (RCA), with technical support of the Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, implemented a Technical Cooperation (TC) project entitled Improving Animal Productivity and Reproductive Efficiency. The dual objectives of this project are (a) strengthening and extending the field applications of Urea Molasses Multinutrient Blocks (UMMB) and other feed supplementation strategies, and (b) monitoring and improving the reproductive management and fertility of smallholder dairy cattle subjected to Artificial Insemination (AI). The radioimmunoassay (RIA) for measurement of progesterone in milk and use of the computer database AIDA (Artificial Insemination Database Application) play important roles in the success of the latter objective. The first meeting to plan project activities was held in January 1999 in Yangon, Myanmar and the second meeting to review progress and develop further work plans was held in February 2000 in Kuala Lumpur, Malaysia. The latter meeting concluded that the procedures currently used by different Asian countries for evaluation of breeding bulls should be standardized and unified protocols developed for ensuring quality control of semen during processing, storage and field use. It was recommended that this should be accomplished through a regional workshop of national consultants. A workshop of national consultants from 10 RCA Member States was therefore held in April 2002 in Faisalabad, Pakistan, to consider and discuss the following aspects and arrive at a consensus on the best procedures and practices to be adopted to suit conditions and needs in developing countries of Asia: - Selection, management and health control of AI bulls; - Semen technologies from collection through processing to storage; - Delivery and follow-up of field AI services to farmers The IAEA has also supported a similar project in

  20. Simultaneous Optimization of Block Replacement and Spare Part Ordering Time for a Multi Component System with Separate Spare Part Ordering for Block and Failure Replacements

    Directory of Open Access Journals (Sweden)

    Farid Mardin

    2016-11-01

    Full Text Available A block replacement schedule can be optimized simultaneously with a spare parts ordering schedule, since all items are replaced at a constant interval. The solution of joint optimization for spare parts ordering time and block replacement gives lower costs compared to separate optimization of ordering time and replacement time. The spare parts for replacement can be classified as stochastic demand for failure replacement and deterministic demand for block replacement. In this paper, we propose a simulation model for a separate spare parts ordering schedule. The solution was compared to the solution for a model with common spare parts for both failure and block replacement. The system has N identical components, each with a Weibull lifetime distribution. The costs of failure and block replacements, and also the costs of ordering, holding and shortage of spare parts are given. The proposed model was shown to perform better than the common order model. Also, compared to the age replacement model, the solution of the proposed model is relatively similar, yet the economies of scale would be an advantage for the block replacement over age replacement.

  1. Biomaterials in Artificial Organs.

    Science.gov (United States)

    Kambic, Helen E.; And Others

    1986-01-01

    Biomaterials are substances or combinations of substances that can be used in a system that treats, augments, or replaces any tissue, organ, or body function. The nature and role of these substances, particularly in the cadiovascular system, are discussed. (JN)

  2. Iron replacement therapy

    DEFF Research Database (Denmark)

    Nielsen, Ole Haagen; Coskun, Mehmet; Weiss, Günter

    2016-01-01

    PURPOSE OF REVIEW: Approximately, one-third of the world's population suffers from anemia, and at least half of these cases are because of iron deficiency. With the introduction of new intravenous iron preparations over the last decade, uncertainty has arisen when these compounds should...... be administered and under which circumstances oral therapy is still an appropriate and effective treatment. RECENT FINDINGS: Numerous guidelines are available, but none go into detail about therapeutic start and end points or how iron-deficiency anemia should be best treated depending on the underlying cause...... of iron deficiency or in regard to concomitant underlying or additional diseases. SUMMARY: The study points to major issues to be considered in revisions of future guidelines for the true optimal iron replacement therapy, including how to assess the need for treatment, when to start and when to stop...

  3. Present state of alloplasty of the knee joint

    Energy Technology Data Exchange (ETDEWEB)

    Schreiber, A.; Suezawa, Y.

    1981-12-01

    Ever since the presumably first knee joint prosthesis was conceived by Gluck in 1880, more than 500 different artificial knee joints have been described in literature up-to-date. Since the long-term results of all these prostheses appear still to be not quite satisfactory, we have attempted to summarize the experience gained with some of the types that many generally be regarded as representative of their respective groups and have described our findings and presented the results obtained by us in an effort to clearly show the present state of alloplasty of the knee joint.

  4. Total knee replacement in patients with diffuse villonodular synovitis

    Directory of Open Access Journals (Sweden)

    Lucio Flávio Biondi Pinheiro Júnior

    Full Text Available ABSTRACT This paper reports a case of diffuse pigmented villonodular synovitis (DPVNS, associated with advanced gonarthrosis, submitted to total knee replacement. The patient had progressive pain and swelling. She had two previous surgeries, firstly arthroscopic , synovectomy and subsequently open synovectomy associated with radiotherapy, with recurrence of the disease. Magnetic resonance imaging revealed diffuse synovitis, advanced arthrosis, and bone cysts. The patient was submitted to a total knee replacement and synovectomy. There was a good postoperative clinical course, with improvement of pain, function, and joint edema on examination. The patient will be followed regarding the possibility of disease recurrence and implant survival.,

  5. Artificial intelligence within AFSC

    Science.gov (United States)

    Gersh, Mark A.

    1990-01-01

    Information on artificial intelligence research in the Air Force Systems Command is given in viewgraph form. Specific research that is being conducted at the Rome Air Development Center, the Space Technology Center, the Human Resources Laboratory, the Armstrong Aerospace Medical Research Laboratory, the Armamant Laboratory, and the Wright Research and Development Center is noted.

  6. Generality in Artificial Intelligence

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 3. Generality in Artificial Intelligence. John McCarthy. Classics Volume 19 Issue 3 March 2014 pp 283-296. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/019/03/0283-0296. Author Affiliations.

  7. Artificial Gravity Research Plan

    Science.gov (United States)

    Gilbert, Charlene

    2014-01-01

    This document describes the forward working plan to identify what countermeasure resources are needed for a vehicle with an artificial gravity module (intermittent centrifugation) and what Countermeasure Resources are needed for a rotating transit vehicle (continuous centrifugation) to minimize the effects of microgravity to Mars Exploration crewmembers.

  8. Artificial Intelligence and CALL.

    Science.gov (United States)

    Underwood, John H.

    The potential application of artificial intelligence (AI) to computer-assisted language learning (CALL) is explored. Two areas of AI that hold particular interest to those who deal with language meaning--knowledge representation and expert systems, and natural-language processing--are described and examples of each are presented. AI contribution…

  9. Generality in Artificial Intelligence

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 3. Generality in Artificial Intelligence. John McCarthy. Classics Volume 19 Issue 3 March 2014 pp 283-296. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/019/03/0283-0296. Author Affiliations.

  10. Smart Collections: Can Artificial Intelligence Tools and Techniques Assist with Discovering, Evaluating and Tagging Digital Learning Resources?

    Science.gov (United States)

    Leibbrandt, Richard; Yang, Dongqiang; Pfitzner, Darius; Powers, David; Mitchell, Pru; Hayman, Sarah; Eddy, Helen

    2010-01-01

    This paper reports on a joint proof of concept project undertaken by researchers from the Flinders University Artificial Intelligence Laboratory in partnership with information managers from the Education Network Australia (edna) team at Education Services Australia to address the question of whether artificial intelligence techniques could be…

  11. In-vivo evaluation of the kinematic behavior of an artificial medial meniscus implant: A pilot study using open-MRI.

    Science.gov (United States)

    De Coninck, Tineke; Elsner, Jonathan J; Linder-Ganz, Eran; Cromheecke, Michiel; Shemesh, Maoz; Huysse, Wouter; Verdonk, René; Verstraete, Koenraad; Verdonk, Peter

    2014-09-01

    In this pilot study we wanted to evaluate the kinematics of a knee implanted with an artificial polycarbonate-urethane meniscus device, designed for medial meniscus replacement. The static kinematic behavior of the implant was compared to the natural medial meniscus of the non-operated knee. A second goal was to evaluate the motion pattern, the radial displacement and the deformation of the meniscal implant. Three patients with a polycarbonate-urethane implant were included in this prospective study. An open-MRI was used to track the location of the implant during static weight-bearing conditions, within a range of motion of 0° to 120° knee flexion. Knee kinematics were evaluated by measuring the tibiofemoral contact points and femoral roll-back. Meniscus measurements (both natural and artificial) included anterior-posterior meniscal movement, radial displacement, and meniscal height. No difference (P>0.05) was demonstrated in femoral roll-back and tibiofemoral contact points during knee flexion between the implanted and the non-operated knees. Meniscal measurements showed no significant difference in radial displacement and meniscal height (P>0.05) at all flexion angles, in both the implanted and non-operated knees. A significant difference (P ≤ 0.05) in anterior-posterior movement during flexion was observed between the two groups. In this pilot study, the artificial polycarbonate-urethane implant, indicated for medial meniscus replacement, had no influence on femoral roll-back and tibiofemoral contact points, thus suggesting that the joint maintains its static kinematic properties after implantation. Radial displacement and meniscal height were not different, but anterior-posterior movement was slightly different between the implant and the normal meniscus. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. MP Joint Arthritis

    Science.gov (United States)

    ... Find a Hand Surgeon Home Anatomy MP Joint Arthritis Email to a friend * required fields From * To * ... important for both pinching and gripping. MP joint arthritis is most common in the thumb and index ...

  13. [Experimental study on novel hybrid artificial trachea transplantation].

    Science.gov (United States)

    Liu, Wenliang; Xiao, Peng; Liang, Hengxing; An, Ran; Cheng, Gang; Yu, Fenglei

    2014-04-01

    We developed and designed a new type of artificial trachea. The basic structure of the artificial trachea was polytetrafluoroethylene vascular prosthesis linked with titanium rings on both sides. Dualmesh was sutured on titanium rings. This experimentation follows the replacement of trachea in dogs with a combined artificial trachea to investigate the feasibility of this type of prosthesis. Sixteen dogs were implanted with the combined artificial trachea after resection of 5 cm of cervical trachea. The 5 cm-long trachea of dogs on the necks were resected and the reconstruction of the defect of the trachea was performed with trachea prosthesis. According to the method of trachea reconstruction, the models were divided into 2 groups, artificial trachea implantation group (the control group, n = 8) and group of artificial trachea implantation with growth factor (the experimental group, n = 8). Then computer tomography scan (CT), bronchoscope and pathologic examination were conducted periodically to observe the healing state of the hybrid artificial trachea. None of the dogs died during operation of cervical segmental trachea construction. But four dogs in the control group died of apnea in succession because artificial trachea was displaced and the lumen was obstructed, while 2 dogs died in the experimental group. In the first month there was granulation around anastomosis with slight stenosis. The rest of dogs were well alive until they were sacrificed 14 months later. The mean survival time of the experimental group was longer than that of the control group. The rate of infection, anastomotic dehiscence, severe stenosis and accidental death in the experimental group were lower than the control group (P anastomosis effectively but infections and split or displacement of the artificial trachea are still major problems affecting long-term survival of the animals. Application of growth factors to a certain extent promotes tissue healing by changing the local environment.

  14. Proprioception in Above-the-Knee Amputees with Artificial Limbs

    Directory of Open Access Journals (Sweden)

    E. P. Latanioti

    2013-01-01

    Full Text Available Purpose. To evaluate the lower limb proprioceptive sensation in patients with femoral amputation who received an artificial joint. Materials and Methods. 22 patients (18 men, 4 women, 24–65 years old (mean: 42, who had undergone above-the-knee joint amputation and underwent evaluation of proprioception using joint reposition in a predetermined angle of 15° knee flexion. The measurements were applied using a conventional goniometer to both amputated and healthy knees. The last ones were used as internal control. All patients performed an active knee flexion from hyperextension to 15° in a closed kinetic chain in order to evaluate proprioceptive sensation of the knee joint using the joint position sense (JPS method during specific controllable circumstances very close to normal gait. Results. JPS at 15° flexion for the amputated knee was calculated to be equal to 13.91 (SD = ±4.74, and for the healthy side it was equal to 14.15 (SD = ±2.61. No statistically significant differences were detected between the amputated and the healthy limb (. Conclusions. The proprioceptive information of the stumps did not appear to be affected significantly after thigh amputation and application of artificial prosthesis when JPS at 15° was evaluated. It seems that these patients compensate the loss of the knee sensory receptors via alternative mechanisms.

  15. Introduction to Artificial Neural Networks

    DEFF Research Database (Denmark)

    Larsen, Jan

    1999-01-01

    The note addresses introduction to signal analysis and classification based on artificial feed-forward neural networks.......The note addresses introduction to signal analysis and classification based on artificial feed-forward neural networks....

  16. Managing Joint Production Motivation

    DEFF Research Database (Denmark)

    Lindenberg, Siegwart; Foss, Nicolai Juul

    2011-01-01

    We contribute to the microfoundations of organizational performance by proffering the construct of joint production motivation. Under such motivational conditions individuals see themselves as part of a joint endeavor, each with his or her own roles and responsibilities; generate shared...... representations of actions and tasks; cognitively coordinate cooperation; and choose their own behaviors in terms of joint goals. Using goal-framing theory, we explain how motivation for joint production can be managed by cognitive/symbolic management and organizational design....

  17. Design of mechanical joints

    CERN Document Server

    Blake, Alexander

    2018-01-01

    A cornerstone publication that covers the basic principles and practical considerations of design methodology for joints held by rivets, bolts, weld seams, and adhesive materials, Design of Mechanical Joints gives engineers the practical results and formulas they need for the preliminary design of mechanical joints, combining the essential topics of joint mechanics...strength of materials...and fracture control to provide a complete treatment of problems pertinent to the field of mechanical connections.

  18. Criminal Aspects of Artificial Abortion

    OpenAIRE

    Hartmanová, Leona

    2016-01-01

    Criminal Aspects of Artificial Abortion This diploma thesis deals with the issue of artificial abortion, especially its criminal aspects. Legal aspects are not the most important aspects of artificial abortion. Social, ethical or ideological aspects are of the same importance but this diploma thesis cannot analyse all of them. The main issue with artificial abortion is whether it is possible to force a pregnant woman to carry a child and give birth to a child when she cannot or does not want ...

  19. Effect of the increase in the height of lumbar disc space on facet joint articulation area in sagittal plane.

    Science.gov (United States)

    Liu, Jiayong; Ebraheim, Nabil A; Haman, Steven P; Shafiq, Qaiser; Karkare, Nakul; Biyani, Ashok; Goel, Vijay K; Woldenberg, Lee

    2006-04-01

    Computerized tomography (CT) of the lumbar spine cadaveric specimens was used to evaluate the effect of increasing the height of the disc space in the lumbar spine to the facet joint articulation in the sagittal plane. To show how the facet joint articulation is affected by increasing the height of the disc space in the lumbar spine. The Charité Artificial Disc (DePuy Spine, Inc., Raynham, MA) was successful in relieving low back pain in the majority of patients, yet there was still a significant number of patients who did not obtain pain relief, or their pain even worsened. The etiology of their pain is still not known. To our knowledge, no study has addressed the effect on the facet joints when the disc height is increased. CT images passing through the center of the L3-S1 facet joints (sagittal plane) were obtained from 15 cadaveric lumbar spine specimens. The articulation overlap of facet joints in sagittal plane from the L3 to S1 was measured. A 1-mm incremental increase to a total 5 mm in disc space height was performed to simulate the changes seen in disc replacement. The change in the facet joint articulation overlap in sagittal plane at normal and each displacement was then measured. There were 5 lumbar spine specimens dissected to validate the technique and standardize the measurements. Mean, percentages, and standard deviation values were calculated for all measured dimensions. No significant difference was found between the measurements on CT and gross specimens (P > 0.05). In 15 specimens, the mean facet joint articulation overlap on the sagittal plane was: 16.29 +/- 1.20 mm (left) and 16.22 +/- 1.16 (right) at the L3-L4 level; 17.81 +/- 1.18 mm (left) and 17.74 +/- 1.18 mm (right) at the L4-L5 level; and 18.18 +/- 1.18 mm (left) and 18.23 +/- 1.15 mm (right) at the L5-S1 level. There is no significant difference between the measured values on left and right sides (P > 0.05). Each 1-mm incremental increase in disc space at the L3-L4 level translated

  20. Artificial Intelligence and Information Retrieval.

    Science.gov (United States)

    Teodorescu, Ioana

    1987-01-01

    Compares artificial intelligence and information retrieval paradigms for natural language understanding, reviews progress to date, and outlines the applicability of artificial intelligence to question answering systems. A list of principal artificial intelligence software for database front end systems is appended. (CLB)

  1. Prosthetic replacement of the medial meniscus in cadaveric knees - Does the prosthesis mimic the functional behavior of the native meniscus?

    NARCIS (Netherlands)

    Tienen, TG; Verdonschot, N; Heijkants, RGJC; Buma, R; Scholten, JGF; van Kampen, A; Veth, RPH

    2004-01-01

    Meniscus replacement by a polymer meniscus prosthesis in dogs resulted in generation of new meniscal tissue. Hypothesis: Optimal functioning of the prosthesis would involve realistic deformation and motion patterns of the prosthesis during knee joint motion. Study Design: Controlled laboratory

  2. Prosthetic replacement of the medial meniscus in cadaveric knees: does the prosthesis mimic the functional behavior of the native meniscus?

    NARCIS (Netherlands)

    Tienen, T.G. van; Verdonschot, N.J.J.; Heijkants, R.G.J.C.; Buma, P.; Scholten, J.G.; Kampen, A. van; Veth, R.P.H.

    2004-01-01

    Meniscus replacement by a polymer meniscus prosthesis in dogs resulted in generation of new meniscal tissue. HYPOTHESIS: Optimal functioning of the prosthesis would involve realistic deformation and motion patterns of the prosthesis during knee joint motion. STUDY DESIGN: Controlled laboratory

  3. Artificial sweeteners are not the answer to childhood obesity.

    Science.gov (United States)

    Swithers, Susan E

    2015-10-01

    While no single factor is responsible for the recent, dramatic increases in overweight and obesity, a scientific consensus has emerged suggesting that consumption of sugar-sweetened products, especially beverages, is casually linked to increases in risk of chronic, debilitating diseases including type 2 diabetes, cardiovascular disease, hypertension and stroke. One approach that might be beneficial would be to replace sugar-sweetened items with products manufactured with artificial sweeteners that provide sweet tastes but with fewer calories. Unfortunately, evidence now indicates that artificial sweeteners are also associated with increased risk of the same chronic diseases linked to sugar consumption. Several biologically plausible mechanisms may explain these counterintuitive negative associations. For example, artificial sweeteners can interfere with basic learning processes that serve to anticipate the normal consequences of consuming sugars, leading to overeating, diminished release of hormones such as GLP-1, and impaired blood glucose regulation. In addition, artificial sweeteners can alter gut microbiota in rodent models and humans, which can also contribute to impaired glucose regulation. Use of artificial sweeteners may also be particularly problematic in children since exposure to hyper-sweetened foods and beverages at young ages may have effects on sweet preferences that persist into adulthood. Taken as a whole, current evidence suggests that a focus on reducing sweetener intake, whether the sweeteners are caloric or non-caloric, remains a better strategy for combating overweight and obesity than use of artificial sweeteners. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Artificial neural networks for decision-making in urologic oncology.

    Science.gov (United States)

    Anagnostou, Theodore; Remzi, Mesut; Lykourinas, Michael; Djavan, Bob

    2003-06-01

    The authors are presenting a thorough introduction in Artificial Neural Networks (ANNs) and their contribution to modern Urologic Oncology. The article covers a description of Artificial Neural Network methodology and points out the differences of Artificial Intelligence to traditional statistic models in terms of serving patients and clinicians, in a different way than current statistical analysis. Since Artificial Intelligence is not yet fully understood by many practicing clinicians, the authors have reviewed a careful selection of articles in order to explore the clinical benefit of Artificial Intelligence applications in modern Urology questions and decision-making. The data are from real patients and reflect attempts to achieve more accurate diagnosis and prognosis, especially in prostate cancer that stands as a good example of difficult decision-making in everyday practice. Experience from current use of Artificial Intelligence is also being discussed, and the authors address future developments as well as potential problems such as medical record quality, precautions in using ANNs or resistance to system use, in an attempt to point out future demands and the need for common standards. The authors conclude that both methods should continue to be used in a complementary manner. ANNs still do not prove always better as to replace standard statistical analysis as the method of choice in interpreting medical data.

  5. Hydrogels as a Replacement Material for Damaged Articular Hyaline Cartilage

    Directory of Open Access Journals (Sweden)

    Charlotte M. Beddoes

    2016-06-01

    Full Text Available Hyaline cartilage is a strong durable material that lubricates joint movement. Due to its avascular structure, cartilage has a poor self-healing ability, thus, a challenge in joint recovery. When severely damaged, cartilage may need to be replaced. However, currently we are unable to replicate the hyaline cartilage, and as such, alternative materials with considerably different properties are used. This results in undesirable side effects, including inadequate lubrication, wear debris, wear of the opposing articular cartilage, and weakening of the surrounding tissue. With the number of surgeries for cartilage repair increasing, a need for materials that can better mimic cartilage, and support the surrounding material in its typical function, is becoming evident. Here, we present a brief overview of the structure and properties of the hyaline cartilage and the current methods for cartilage repair. We then highlight some of the alternative materials under development as potential methods of repair; this is followed by an overview of the development of tough hydrogels. In particular, double network (DN hydrogels are a promising replacement material, with continually improving physical properties. These hydrogels are coming closer to replicating the strength and toughness of the hyaline cartilage, while offering excellent lubrication. We conclude by highlighting several different methods of integrating replacement materials with the native joint to ensure stability and optimal behaviour.

  6. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has...... made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction....... It reviews calibration procedures, outlines the computational algorithms, and summarizes examplary applications. Four different platforms for BD and DPD simulations are presented that differ in their focus, features, and complexity....

  7. Wide Band Artificial Pulsar

    Science.gov (United States)

    Parsons, Zackary

    2017-01-01

    The Wide Band Artificial Pulsar (WBAP) is an instrument verification device designed and built by the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virgina. The site currently operates the Green Bank Ultimate Pulsar Processing Instrument (GUPPI) and the Versatile Green Bank Astronomical Spectrometer (VEGAS) digital backends for their radio telescopes. The commissioning and continued support for these sophisticated backends has demonstrated a need for a device capable of producing an accurate artificial pulsar signal. The WBAP is designed to provide a very close approximation to an actual pulsar signal. This presentation is intended to provide an overview of the current hardware and software implementations and to also share the current results from testing using the WBAP.

  8. Artificial structures on Mars

    Science.gov (United States)

    Van Flandern, T.

    2002-05-01

    Approximately 70,000 images of the surface of Mars at a resolution of up to 1.4 meters per pixel, taken by the Mars Global Surveyor spacecraft, are now in public archives. Approximately 1% of those images show features that can be broadly described as `special shapes', `tracks, trails, and possible vegetation', `spots, stripes, and tubes', `artistic imagery', and `patterns and symbols'. Rather than optical illusions and tricks of light and shadow, most of these have the character that, if photographed on Earth, no one would doubt that they were the products of large biology and intelligence. In a few cases, relationships, context, and fulfillment of a priori predictions provide objective evidence of artificiality that is exempt from the influence of experimenter biases. Only controlled test results can be trusted because biases are strong and operate both for and against artificiality.

  9. Antenna Controller Replacement Software

    Science.gov (United States)

    Chao, Roger Y.; Morgan, Scott C.; Strain, Martha M.; Rockwell, Stephen T.; Shimizu, Kenneth J.; Tehrani, Barzia J.; Kwok, Jaclyn H.; Tuazon-Wong, Michelle; Valtier, Henry; Nalbandi, Reza; hide

    2010-01-01

    The Antenna Controller Replacement (ACR) software accurately points and monitors the Deep Space Network (DSN) 70-m and 34-m high-efficiency (HEF) ground-based antennas that are used to track primarily spacecraft and, periodically, celestial targets. To track a spacecraft, or other targets, the antenna must be accurately pointed at the spacecraft, which can be very far away with very weak signals. ACR s conical scanning capability collects the signal in a circular pattern around the target, calculates the location of the strongest signal, and adjusts the antenna pointing to point directly at the spacecraft. A real-time, closed-loop servo control algorithm performed every 0.02 second allows accurate positioning of the antenna in order to track these distant spacecraft. Additionally, this advanced servo control algorithm provides better antenna pointing performance in windy conditions. The ACR software provides high-level commands that provide a very easy user interface for the DSN operator. The operator only needs to enter two commands to start the antenna and subreflector, and Master Equatorial tracking. The most accurate antenna pointing is accomplished by aligning the antenna to the Master Equatorial, which because of its small size and sheltered location, has the most stable pointing. The antenna has hundreds of digital and analog monitor points. The ACR software provides compact displays to summarize the status of the antenna, subreflector, and the Master Equatorial. The ACR software has two major functions. First, it performs all of the steps required to accurately point the antenna (and subreflector and Master Equatorial) at the spacecraft (or celestial target). This involves controlling the antenna/ subreflector/Master-Equatorial hardware, initiating and monitoring the correct sequence of operations, calculating the position of the spacecraft relative to the antenna, executing the real-time servo control algorithm to maintain the correct position, and

  10. 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.

  11. 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.

  12. Essentials of artificial intelligence

    CERN Document Server

    Ginsberg, Matt

    1993-01-01

    Since its publication, Essentials of Artificial Intelligence has beenadopted at numerous universities and colleges offering introductory AIcourses at the graduate and undergraduate levels. Based on the author'scourse at Stanford University, the book is an integrated, cohesiveintroduction to the field. The author has a fresh, entertaining writingstyle that combines clear presentations with humor and AI anecdotes. At thesame time, as an active AI researcher, he presents the materialauthoritatively and with insight that reflects a contemporary, first hand

  13. Intelligence in Artificial Intelligence

    OpenAIRE

    Datta, Shoumen Palit Austin

    2016-01-01

    The elusive quest for intelligence in artificial intelligence prompts us to consider that instituting human-level intelligence in systems may be (still) in the realm of utopia. In about a quarter century, we have witnessed the winter of AI (1990) being transformed and transported to the zenith of tabloid fodder about AI (2015). The discussion at hand is about the elements that constitute the canonical idea of intelligence. The delivery of intelligence as a pay-per-use-service, popping out of ...

  14. Intelligence, Artificial and Otherwise

    OpenAIRE

    Chace, William M.

    1984-01-01

    I rise now to speak with the assumption that all of you know very well what I am going to say. I am the humanist here, the professor of English. We humanists, when asked to speak on questions of science and technology, are notorious for offering an embarrassed and ignorant respect toward those matters, a respect, however, which can all too quickly degenerate into insolent condescension. Face to face with the reality of computer technology, say, or with "artificial intelligence," we humanists ...

  15. Impacts of Artificial Intelligence

    OpenAIRE

    Trappl, R.

    1986-01-01

    This book, which is intended to serve as the first stage in an iterative process of detecting, predicting, and assessing the impacts of Artificial Intelligence opens with a short "one-hour course" in AI, which is intended to provide a nontechnical informative introduction to the material which follows. Next comes an overview chapter which is based on an extensive literature search, the position papers, and discussions. The next section of the book contains position papers whose richness...

  16. Ethical Artificial Intelligence

    OpenAIRE

    Hibbard, Bill

    2014-01-01

    This book-length article combines several peer reviewed papers and new material to analyze the issues of ethical artificial intelligence (AI). The behavior of future AI systems can be described by mathematical equations, which are adapted to analyze possible unintended AI behaviors and ways that AI designs can avoid them. This article makes the case for utility-maximizing agents and for avoiding infinite sets in agent definitions. It shows how to avoid agent self-delusion using model-based ut...

  17. Artificial neural network modelling

    CERN Document Server

    Samarasinghe, Sandhya

    2016-01-01

    This book covers theoretical aspects as well as recent innovative applications of Artificial Neural networks (ANNs) in natural, environmental, biological, social, industrial and automated systems. It presents recent results of ANNs in modelling small, large and complex systems under three categories, namely, 1) Networks, Structure Optimisation, Robustness and Stochasticity 2) Advances in Modelling Biological and Environmental Systems and 3) Advances in Modelling Social and Economic Systems. The book aims at serving undergraduates, postgraduates and researchers in ANN computational modelling. .

  18. Modeling artificial leaf

    OpenAIRE

    Raucci, Umberto

    2016-01-01

    The development of efficient artificial leaves relies on the subtle combination of the electronic structure of molecular assemblies able to absorbing sunlight, converting light energy into electrochemical potential energy and finally transducing it into chemical accessible energy. The electronical design of these charge transfer molecular machine is crucial to build up a complex supramolecular architecture for the light energy conversion. The theoretical computational approach represent...

  19. Artificial perception and consciousness

    Science.gov (United States)

    Caulfield, H. John; Johnson, John L.

    2000-06-01

    Perception has both unconscious and conscious aspects. In all cases, however, what we perceive is a model of reality. By brain construction through evolution, we divide the world into two parts--our body and the outside world. But the process is the same in both cases. We perceive a construct usually governed by sensed data but always involving memory, goals, fears, expectations, etc. As a first step toward Artificial Perception in man-made systems, we examine perception in general here.

  20. Artificial sweetener; Jinko kanmiryo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-08-01

    The patents related to the artificial sweetener that it is introduced to the public in 3 years from 1996 until 1998 are 115 cases. The sugar quality which makes an oligosaccharide and sugar alcohol the subject is greatly over 28 cases of the non-sugar quality in the one by the kind as a general tendency of these patents at 73 cases in such cases as the Aspartame. The method of manufacture patent, which included new material around other peptides, the oligosaccharide and sugar alcohol isn`t inferior to 56 cases of the formation thing patent at 43 cases, and pays attention to the thing, which is many by the method of manufacture, formation. There is most improvement of the quality of sweetness with 31 cases in badness of the aftertaste which is characteristic of the artificial sweetener and so on, and much stability including the improvement in the flavor of food by the artificial sweetener, a long time and dissolution, fluid nature and productivity and improvement of the economy such as a cost are seen with effect on a purpose. (NEDO)

  1. Biphasic and boundary lubrication mechanisms in artificial hydrogel cartilage: A review.

    Science.gov (United States)

    Murakami, Teruo; Yarimitsu, Seido; Nakashima, Kazuhiro; Sakai, Nobuo; Yamaguchi, Tetsuo; Sawae, Yoshinori; Suzuki, Atsushi

    2015-12-01

    Various studies on the application of artificial hydrogel cartilage to cartilage substitutes and artificial joints have been conducted. It is expected in clinical application of artificial hydrogel cartilage that not only soft-elastohydrodynamic lubrication but biphasic, hydration, gel-film and boundary lubrication mechanisms will be effective to sustain extremely low friction and minimal wear in daily activities similar to healthy natural synovial joints with adaptive multimode lubrication. In this review article, the effectiveness of biphasic lubrication and boundary lubrication in hydrogels in thin film condition is focused in relation to the structures and properties of hydrogels. As examples, the tribological behaviors in three kinds of poly(vinyl alcohol) hydrogels with high water content are compared, and the importance of lubrication mechanism in biomimetic artificial hydrogel cartilage is discussed to extend the durability of cartilage substitute. © IMechE 2015.

  2. Preoperative widespread pain sensitization and chronic pain after hip and knee replacement: a cohort analysis

    Science.gov (United States)

    Wylde, Vikki; Sayers, Adrian; Lenguerrand, Erik; Gooberman-Hill, Rachael; Pyke, Mark; Beswick, Andrew D.; Dieppe, Paul; Blom, Ashley W.

    2015-01-01

    Abstract Chronic pain after joint replacement is common, affecting approximately 10% of patients after total hip replacement (THR) and 20% of patients after total knee replacement (TKR). Heightened generalized sensitivity to nociceptive input could be a risk factor for the development of this pain. The primary aim of this study was to investigate whether preoperative widespread pain sensitivity was associated with chronic pain after joint replacement. Data were analyzed from 254 patients receiving THR and 239 patients receiving TKR. Pain was assessed preoperatively and at 12 months after surgery using the Western Ontario and McMaster Universities Osteoarthritis Pain Scale. Preoperative widespread pain sensitivity was assessed through measurement of pressure pain thresholds (PPTs) at the forearm using an algometer. Statistical analysis was conducted using linear regression and linear mixed models, and adjustments were made for confounding variables. In both the THR and TKR cohort, lower PPTs (heightened widespread pain sensitivity) were significantly associated with higher preoperative pain severity. Lower PPTs were also significantly associated with higher pain severity at 12 months after surgery in the THR cohort. However, PPTs were not associated with the change in pain severity from preoperative to 12 months postoperative in either the TKR or THR cohort. These findings suggest that although preoperative widespread pressure pain sensitivity is associated with pain severity before and after joint replacement, it is not a predictor of the amount of pain relief that patients gain from joint replacement surgery, independent of preoperative pain severity. PMID:25599300

  3. Transforming Normal Programs by Replacement

    NARCIS (Netherlands)

    Bossi, Annalisa; Pettorossi, A.; Cocco, Nicoletta; Etalle, Sandro

    1992-01-01

    The replacement transformation operation, already defined in [28], is studied wrt normal programs. We give applicability conditions able to ensure the correctness of the operation wrt Fitting's and Kunen's semantics. We show how replacement can mimic other transformation operations such as thinning,

  4. Apixaban or enoxaparin for thromboprophylaxis after knee replacement

    DEFF Research Database (Denmark)

    Lassen, Michael Rud; Raskob, Gary E; Gallus, Alexander

    2009-01-01

    BACKGROUND: The optimal strategy for thromboprophylaxis after major joint replacement has not been established. Low-molecular-weight heparins such as enoxaparin predominantly target factor Xa but to some extent also inhibit thrombin. Apixaban, a specific factor Xa inhibitor, may provide effective...... thromboprophylaxis with a low risk of bleeding and improved ease of use. METHODS: In a double-blind, double-dummy study, we randomly assigned patients undergoing total knee replacement to receive 2.5 mg of apixaban orally twice daily or 30 mg of enoxaparin subcutaneously every 12 hours. Both medications were started...... (P=0.03). CONCLUSIONS: As compared with enoxaparin for efficacy of thromboprophylaxis after knee replacement, apixaban did not meet the prespecified statistical criteria for noninferiority, but its use was associated with lower rates of clinically relevant bleeding and it had a similar adverse...

  5. Recent Patents and Designs on Hip Replacement Prostheses

    Science.gov (United States)

    Derar, H; Shahinpoor, M

    2015-01-01

    Hip replacement surgery has gone through tremendous evolution since the first procedure in 1840. In the past five decades the advances that have been made in technology, advanced and smart materials innovations, surgical techniques, robotic surgery and methods of fixations and sterilization, facilitated hip implants that undergo multiple design revolutions seeking the least problematic implants and a longer survivorship. Hip surgery has become a solution for many in need of hip joint remedy and replacement across the globe. Nevertheless, there are still long-term problems that are essential to search and resolve to find the optimum implant. This paper reviews several recent patents on hip replacement surgery. The patents present various designs of prostheses, different materials as well as methods of fixation. Each of the patents presents a new design as a solution to different issues ranging from the longevity of the hip prostheses to discomfort and inconvenience experienced by patients in the long-term. PMID:25893020

  6. Opinion on Dutch children and the intake of artificial sweeteners

    OpenAIRE

    Netherlands Food and Consumer Product Safety Authority

    2009-01-01

    The food industry is looking at possibilities to reduce, amongst others, the amount of sugar in food. Sugar can be replaced by sweeteners. The intake of artificial, non nutritive sweeteners of young Dutch children was estimated and compared to the health limit (ADI). An ADI (Acceptable Daily Intake) is the amount of a food additive, expressed as milligrams per kilogram of body weight, which can be ingested daily throughout life without causing additional health risks. The most commonly used s...

  7. Minimally invasive aortic valve replacement

    DEFF Research Database (Denmark)

    Foghsgaard, Signe; Schmidt, Thomas Andersen; Kjaergard, Henrik K

    2009-01-01

    In this descriptive prospective study, we evaluate the outcomes of surgery in 98 patients who were scheduled to undergo minimally invasive aortic valve replacement. These patients were compared with a group of 50 patients who underwent scheduled aortic valve replacement through a full sternotomy...... operations were completed as mini-sternotomies, 4 died later of noncardiac causes. The aortic cross-clamp and perfusion times were significantly different across all groups (P replacement...... is an excellent operation in selected patients, but its true advantages over conventional aortic valve replacement (other than a smaller scar) await evaluation by means of randomized clinical trial. The "extended mini-aortic valve replacement" operation, on the other hand, is a risky procedure that should...

  8. On total disc replacement.

    Science.gov (United States)

    Berg, Svante

    2011-02-01

    Low back pain consumes a large part of the community's resources dedicated to health care and sick leave. Back disorders also negatively affect the individual leading to pain suffering, decreased quality-of-life and disability. Chronic low back pain (CLBP) due to degenerative disc disease (DDD) is today often treated with fusion when conservative treatment has failed and symptoms are severe. This treatment is as successful as arthroplasty is for hip arthritis in restoring the patient's quality of life and reducing disability. Even so, there are some problems with this treatment, one of these being recurrent CLBP from an adjacent segment (ASD) after primarily successful surgery. This has led to the development of alternative surgical treatments and devices that maintain or restore mobility, in order to reduce the risk for ASD. Of these new devices, the most frequently used are the disc prostheses used in Total Disc Replacement (TDR). This thesis is based on four studies comparing total disc replacement with posterior fusion. The studies are all based on a material of 152 patients with DDD in one or two segments, aged 20-55 years that were randomly treated with either posterior fusion or TDR. The first study concerned clinical outcome and complications. Follow-up was 100% at both one and two years. It revealed that both treatment groups had a clear benefit from treatment and that patients with TDR were better in almost all outcome scores at one-year follow-up. Fusion patients continued to improve during the second year. At two-year follow-up there was a remaining difference in favour of TDR for back pain. 73% in the TDR group and 63% in the fusion group were much better or totally pain-free (n.s.), while twice as many patients in the TDR group were totally pain free (30%) compared to the fusion group (15%). Time of surgery and total time in hospital were shorter in the TDR group. There was no difference in complications and reoperations, except that seventeen of the

  9. Visual detection of defects in solder joints

    Science.gov (United States)

    Blaignan, V. B.; Bourbakis, Nikolaos G.; Moghaddamzadeh, Ali; Yfantis, Evangelos A.

    1995-03-01

    The automatic, real-time visual acquisition and inspection of VLSI boards requires the use of machine vision and artificial intelligence methodologies in a new `frame' for the achievement of better results regarding efficiency, products quality and automated service. In this paper the visual detection and classification of different types of defects on solder joints in PC boards is presented by combining several image processing methods, such as smoothing, segmentation, edge detection, contour extraction and shape analysis. The results of this paper are based on simulated solder defects and a real one.

  10. Liquid crystals in biotribology synovial joint treatment

    CERN Document Server

    Ermakov, Sergey; Eismont, Oleg; Nikolaev, Vladimir

    2016-01-01

    This book summarizes the theoretical and experimental studies confirming the concept of the liquid-crystalline nature of boundary lubrication in synovial joints. It is shown that cholesteric liquid crystals in the synovial liquid play a significant role in the mechanism of intra-articular friction reduction. The results of structural, rheological and tribological research of the creation of artificial synovial liquids - containing cholesteric liquid crystals in natural synovial liquids - are described. These liquid crystals reproduce the lubrication properties of natural synovia and provide a high chondroprotective efficiency. They were tested in osteoarthritis models and in clinical practice.

  11. Kinematic Analysis of 3-DOF Planer Robot Using Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Jolly Atit Shah

    2012-07-01

    Full Text Available Automatic control of the robotic manipulator involves study of kinematics and dynamics as a major issue. This paper involves the forward and inverse kinematics of 3-DOF robotic manipulator with revolute joints. In this study the Denavit- Hartenberg (D-H model is used to model robot links and joints. Also forward and inverse kinematics solution has been achieved using Artificial Neural Networks for 3-DOF robotic manipulator. It shows that by using artificial neural network the solution we get is faster, acceptable and has zero error.

  12. Post-operative X-ray morphology: Joints

    International Nuclear Information System (INIS)

    Vogel, H.

    1987-01-01

    The description of X-ray findings after operations with the object of implanting protheses in joints makes up most of the contents of this book. The reconstruction of joints after trauma is only marginally dealt with. Among the various indications for implanting protheses, the replacement of joints destroyed by wear and trauma is the most important. Also considered were X-ray examinations after hallux-valgus operations and plastic surgery on hands and feet, as well as X-ray findings following operations on the lumbar part of the vertebral column (disc surgery). (orig./MG) [de

  13. Artificial Leaf Based on Artificial Photosynthesis for Solar Fuel Production

    Science.gov (United States)

    2017-06-30

    demonstration that the conversion efficiency of CO2 to formic acid in a photo reduction reactor combining a photosensitizer and formate dehydrogenase (FDH) was...We believe that this contribution is theoretically and practically relevant because the artificial photosynthetic system developed has potential...based on the artificial photosynthesis, “artificial leaf” are proposed as for an example illustrated in Scheme 1: 1) CO2 reduction to chemical

  14. What Exactly Is Jointness?

    National Research Council Canada - National Science Library

    Wilkerson, Lawrence

    1997-01-01

    ... it right and well-and their feeling the same way about you. All frills and lobbying aside, the essence of jointness is understanding and trust. As General Colin Powell stated in the first edition of Joint Pub 1, "jolnt warfare is team warfare." But what about seamlessness, synergy, joint doctrine, interoperability, and all the other buzzwords? Let's examine some of the more prevalent ones.

  15. Concerns Over the Expansion of Artificial Intelligence in the Legal Field

    OpenAIRE

    Einhouse, Ben

    2018-01-01

    Cornell Law School J.D. Student Research Papers. 38 Advances in technology have surely made the practice of law more efficient, but looming advances in artificial intelligence should raise some concern about the price of this efficiency. Artificial intelligence programs already exhibit the capacity to replace the daily activities of some lawyers, which should raise some concern in the legal community, especially regarding legal ethics. Despite these concerns, the access to knowledge that arti...

  16. PERCEPTION OF MEDICAL STUDENTS TOWARDS ARTIFICIAL BONES AND POP MODELS OF VISCERA

    OpenAIRE

    Sumit Tulshidas Patil; Nazia Quadir; Rashmi Deopujari; Vivekanand Gajbhiye

    2015-01-01

    Background: In learning of anatomy, bones and viscera are very important. Now days, artificial bones are replacing the original bones for study purpose due to unavailability. Original viscera are available for students only at dissection hours. So we have tried to find out perception of medical students towards artificial bones and POP models of viscera. Materials and Methods: We had prepared a questionnaire consisting of 20 questions, 10 related to bones and 10 related to the POP models o...

  17. Artificial intelligence in hematology.

    Science.gov (United States)

    Zini, Gina

    2005-10-01

    Artificial intelligence (AI) is a computer based science which aims to simulate human brain faculties using a computational system. A brief history of this new science goes from the creation of the first artificial neuron in 1943 to the first artificial neural network application to genetic algorithms. The potential for a similar technology in medicine has immediately been identified by scientists and researchers. The possibility to store and process all medical knowledge has made this technology very attractive to assist or even surpass clinicians in reaching a diagnosis. Applications of AI in medicine include devices applied to clinical diagnosis in neurology and cardiopulmonary diseases, as well as the use of expert or knowledge-based systems in routine clinical use for diagnosis, therapeutic management and for prognostic evaluation. Biological applications include genome sequencing or DNA gene expression microarrays, modeling gene networks, analysis and clustering of gene expression data, pattern recognition in DNA and proteins, protein structure prediction. In the field of hematology the first devices based on AI have been applied to the routine laboratory data management. New tools concern the differential diagnosis in specific diseases such as anemias, thalassemias and leukemias, based on neural networks trained with data from peripheral blood analysis. A revolution in cancer diagnosis, including the diagnosis of hematological malignancies, has been the introduction of the first microarray based and bioinformatic approach for molecular diagnosis: a systematic approach based on the monitoring of simultaneous expression of thousands of genes using DNA microarray, independently of previous biological knowledge, analysed using AI devices. Using gene profiling, the traditional diagnostic pathways move from clinical to molecular based diagnostic systems.

  18. Artificial mismatch hybridization

    Science.gov (United States)

    Guo, Zhen; Smith, Lloyd M.

    1998-01-01

    An improved nucleic acid hybridization process is provided which employs a modified oligonucleotide and improves the ability to discriminate a control nucleic acid target from a variant nucleic acid target containing a sequence variation. The modified probe contains at least one artificial mismatch relative to the control nucleic acid target in addition to any mismatch(es) arising from the sequence variation. The invention has direct and advantageous application to numerous existing hybridization methods, including, applications that employ, for example, the Polymerase Chain Reaction, allele-specific nucleic acid sequencing methods, and diagnostic hybridization methods.

  19. Uncertainty in artificial intelligence

    CERN Document Server

    Kanal, LN

    1986-01-01

    How to deal with uncertainty is a subject of much controversy in Artificial Intelligence. This volume brings together a wide range of perspectives on uncertainty, many of the contributors being the principal proponents in the controversy.Some of the notable issues which emerge from these papers revolve around an interval-based calculus of uncertainty, the Dempster-Shafer Theory, and probability as the best numeric model for uncertainty. There remain strong dissenting opinions not only about probability but even about the utility of any numeric method in this context.

  20. The artificial bladder.

    Science.gov (United States)

    Desgrandchamps, F; Griffith, D P

    1999-04-01

    An artificial bladder should provide adequate urine storage, allow volitional complete evacuation of urine and preserve renal function. Moreover, its structure has to be biocompatible, resistant to urinary encrustation and tolerant to bacterial infection. Various solutions have been proposed over the years to achieve these multiple requirements. However, most of these solutions and their corresponding prototypes did not advance beyond the stage of a preliminary report of experimental data. This review will bring out the 'proof of principal' in alloplastic prosthetic bladder, including type of alloplast and design concept and the recent development in tissue engineering approaches.